0000950170-23-039831 | 10-Q | XBRL Viewer

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Composition of Certain Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Balance Sheet Related Disclosures [Abstract]
Depreciation and amortization expense	$ 1,400	$ 1,300	$ 2,732	$ 2,467

Term Debt	6 Months Ended
Jun. 30, 2023
Debt Instruments [Abstract]
Term Debt	Note 8. Term Debt In 2017, the Company entered into a loan and security agreement with Oxford Finance LLC (“Oxford”), which was subsequently amended (“Amended Loan Agreement”), pursuant to which the Company borrowed $20.0 million under a Term A loan and $10.0 million under a Term B loan. In February 2022, the Company entered into a new Loan and Security Agreement (“2022 Loan Agreement”) with Oxford. Pursuant to the terms of the 2022 Loan Agreement, the Company borrowed $60.0 million in term loans (the “Term Loans”), of which $31.6 million was used to repay the balance outstanding under the Amended Loan Agreement, including $0.2 million of accrued interest. Under the 2022 Loan Agreement the initial interest-only period was through April 1, 2025, followed by 23 equal monthly payments of principal and applicable interest. In September 2022, a qualifying equity event, as defined in the 2022 Loan Agreement, was achieved which extended the interest-only period through April 1, 2026, followed by 11 equal monthly payments of principal and applicable interest. As a result, all amounts outstanding under the 2022 Loan Agreement will mature on February 1, 2027 (the “Maturity Date”). In connection with the repayment of the balance outstanding under the Amended Loan Agreement, the Company incurred amendment and final payment fees of $1.5 million previously due on the earlier of (i) the maturity date, (ii) acceleration of any Amended Loan Agreement loans, or (iii) the prepayment of any Amended Loan Agreement loans. The Company accounted for this amendment as debt modification in accordance with ASC Topic 470, Debt because the modification was not considered substantial. The balance outstanding under the 2022 Loan Agreement initially bore interest at a floating per annum rate equal to 7.83% plus the greater of (a) the 30-day U.S. Dollar (USD) LIBOR rate and (b) 0.11%. The interest rate applicable to the Term Loans as of June 30, 2023 was 13.02% per annum. The 2022 Loan Agreement included a provision addressing replacement of LIBOR with an alternate benchmark rate, when LIBOR was phased out in June 2023. Effective July 1, 2023, the balance outstanding under the 2022 Loan Agreement bears interest at a floating per annum rate equal to the greater of (a) 7.94% and (b) the sum of (i) the 1-Month CME Term Secured Overnight Financing Rate (“SOFR”) on the last business day of the month that immediately precedes the month in which the interest will accrue, (ii) 0.10% and (iii) 7.83%. The Company is required to make a final payment fee of 7.5% of the principal balance outstanding, payable on the earlier of (i) the Maturity Date, (ii) acceleration of any Term Loan, or (iii) the prepayment of the Term Loan. As of June 30, 2023, there was $60.0 million outstanding under the Term Loans. In connection with the Amended Loan Agreement, the Company previously incurred debt issuance costs of $1.5 million, which have been recorded as a debt discount and are being accreted to interest expense over the term of the Term Loans. Interest on the Term Loans, consisting of the stated interest rate, final payment fee and amortization of the discount, is being recognized under the effective interest method using a rate of 14.51%. As of June 30, 2023, the balance of the unamortized debt discount was $1.6 million. The balance of the accrued final payment fee was $2.3 million as of June 30, 2023 and is presented as other long-term liability in the accompanying condensed consolidated balance sheet. The Company has an option to repay the outstanding debt under the 2022 Loan Agreement at any time in increments of $5.0 million, subject to a prepayment fee of 1.00% if the Term Loans are prepaid on or prior to February 22, 2024, after which no prepayment penalty would be applied. The Company may use the proceeds from the Term Loans solely for its working capital requirements and to fund its general business operations. The Company’s obligations under the 2022 Loan Agreement are secured by a first priority security interest in substantially all of its current and future assets, other than its intellectual property. In addition, the Company has also agreed not to encumber its intellectual property assets, except as permitted by the 2022 Loan Agreement. While any amounts are outstanding under the 2022 Loan Agreement, the Company is subject to a number of affirmative and restrictive covenants, including covenants regarding dispositions of property, business combinations or acquisitions, among other customary covenants. The Company is also restricted from declaring dividends or making other distributions or payments on its capital stock in excess of $0.3 million per calendar year, subject to limited exceptions. As of June 30, 2023, the Company was in compliance with all covenants under the 2022 Loan Agreement.

Term Debt

6 Months Ended

Jun. 30, 2023

Debt Instruments [Abstract]

Term Debt

Note 8. Term Debt

In 2017, the Company entered into a loan and security agreement with Oxford Finance LLC (“Oxford”), which was subsequently amended (“Amended Loan Agreement”), pursuant to which the Company borrowed $20.0 million under a Term A loan and $10.0 million under a Term B loan.

In February 2022, the Company entered into a new Loan and Security Agreement (“2022 Loan Agreement”) with Oxford. Pursuant to the terms of the 2022 Loan Agreement, the Company borrowed $60.0 million in term loans (the “Term Loans”), of which $31.6 million was used to repay the balance outstanding under the Amended Loan Agreement, including $0.2 million of accrued interest. Under the 2022 Loan Agreement the initial interest-only period was through April 1, 2025, followed by 23 equal monthly payments of principal and applicable interest. In September 2022, a qualifying equity event, as defined in the 2022 Loan Agreement, was achieved which extended the interest-only period through April 1, 2026, followed by 11 equal monthly payments of principal and applicable interest. As a result, all amounts outstanding under the 2022 Loan Agreement will mature on February 1, 2027 (the “Maturity Date”). In connection with the repayment of the balance outstanding under the Amended Loan Agreement, the Company incurred amendment and final payment fees of $1.5 million previously due on the earlier of (i) the maturity date, (ii) acceleration of any Amended Loan Agreement loans, or (iii) the prepayment of any Amended Loan Agreement loans.

The Company accounted for this amendment as debt modification in accordance with ASC Topic 470, Debt because the modification was not considered substantial.

The balance outstanding under the 2022 Loan Agreement initially bore interest at a floating per annum rate equal to 7.83% plus the greater of (a) the 30-day U.S. Dollar (USD) LIBOR rate and (b) 0.11%. The interest rate applicable to the Term Loans as of June 30, 2023 was 13.02% per annum. The 2022 Loan Agreement included a provision addressing replacement of LIBOR with an alternate benchmark rate, when LIBOR was phased out in June 2023. Effective July 1, 2023, the balance outstanding under the 2022 Loan Agreement bears interest at a floating per annum rate equal to the greater of (a) 7.94% and (b) the sum of (i) the 1-Month CME Term Secured Overnight Financing Rate (“SOFR”) on the last business day of the month that immediately precedes the month in which the interest will accrue, (ii) 0.10% and (iii) 7.83%. The Company is required to make a final payment fee of 7.5% of the principal balance outstanding, payable on the earlier of (i) the Maturity Date, (ii) acceleration of any Term Loan, or (iii) the prepayment of the Term Loan. As of June 30, 2023, there was $60.0 million outstanding under the Term Loans. In connection with the Amended Loan Agreement, the Company previously incurred debt issuance costs of $1.5 million, which have been recorded as a debt discount and are being accreted to interest expense over the term of the Term Loans. Interest on the Term Loans, consisting of the stated interest rate, final payment fee and amortization of the discount, is being recognized under the effective interest method using a rate of 14.51%. As of June 30, 2023, the balance of the unamortized debt discount was $1.6 million. The balance of the accrued final payment fee was

$2.3 million as of June 30, 2023 and is presented as other long-term liability in the accompanying condensed consolidated balance sheet.

The Company has an option to repay the outstanding debt under the 2022 Loan Agreement at any time in increments of $5.0 million, subject to a prepayment fee of 1.00% if the Term Loans are prepaid on or prior to February 22, 2024, after which no prepayment penalty would be applied.

The Company may use the proceeds from the Term Loans solely for its working capital requirements and to fund its general business operations. The Company’s obligations under the 2022 Loan Agreement are secured by a first priority security interest in substantially all of its current and future assets, other than its intellectual property. In addition, the Company has also agreed not to encumber its intellectual property assets, except as permitted by the 2022 Loan Agreement. While any amounts are outstanding under the 2022 Loan Agreement, the Company is subject to a number of affirmative and restrictive covenants, including covenants regarding dispositions of property, business combinations or acquisitions, among other customary covenants. The Company is also restricted from declaring dividends or making other distributions or payments on its capital stock in excess of $0.3 million per calendar year, subject to limited exceptions. As of June 30, 2023, the Company was in compliance with all covenants under the 2022 Loan Agreement.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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-Subparagraph (g)
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Nature of Business and Basis of Presentation	6 Months Ended
Jun. 30, 2023
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	Note 1. Nature of Business and Basis of Presentation Nature of Operations Poseida Therapeutics, Inc. (the “Company” or “Poseida”) is a clinical-stage cell and gene therapy company advancing a new class of treatments for patients with cancer and rare diseases. The Company has discovered and is developing a broad portfolio of product candidates in a variety of indications based on its core proprietary platforms, including its non-viral piggyBac DNA Delivery System, Cas-CLOVER Site-specific Gene Editing System and nanoparticle- and AAV-based gene delivery technologies. The Company is subject to risks and uncertainties common to development-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s therapeutic development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. Liquidity and Capital Resources The Company has experienced net losses and negative cash flows from operations since its inception and has relied on its ability to fund its operations primarily through equity and debt financings and strategic collaborations. For the six months ended June 30, 2023, the Company incurred a net loss of $66.3 million and negative cash flows from operations of $71.3 million. The Company expects it will continue to incur net losses and negative cash flows from operations for at least the next several years. As of June 30, 2023, the Company had an accumulated deficit of $537.2 million. The Company expects that its cash, cash equivalents and short-term investments as of June 30, 2023 of $214.6 million will be sufficient to fund its operations for at least the next twelve months from the date of issuance of these condensed consolidated financial statements. In the long term, the Company will need additional financing to support its continuing operations and pursue its business strategy. Until such time as the Company can generate significant revenue from product sales, if ever, it expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances, and licensing arrangements. The Company may be unable to raise additional funds or enter into such other agreements when needed on favorable terms or at all. The inability to raise capital as and when needed would have a negative impact on the Company’s financial condition and its ability to pursue its business strategy. The Company will need to generate significant revenue to achieve profitability, and it may never do so. Basis of Presentation and Consolidation The accompanying condensed consolidated financial statements reflect the Company’s financial position, results of operations and cash flows, in conformity with generally accepted accounting principles in the United States of America (“GAAP”), for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The accompanying condensed consolidated financial statements include the accounts of Poseida Therapeutics, Inc. and its wholly owned subsidiary. All intercompany transactions and balances have been eliminated. These unaudited condensed consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary to fairly state the financial position and the results of its operations and cash flows for interim periods presented. Interim-period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the Securities and Exchange Commission (“SEC”) on March 9, 2023 from which the Company derived its condensed consolidated balance sheet as of December 31, 2022. Risk and Uncertainties Global events such as Russia’s invasion of Ukraine and the retaliatory measures that have been taken, or could be taken in the future, by the United States, NATO, and other countries have created global security concerns that could result in a regional conflict and otherwise have a lasting impact on regional and global economies, any or all of which could disrupt the Company’s supply chain and adversely affect its ability to conduct ongoing and future clinical trials of the Company’s product candidates. The extent to which any such ongoing or future conflict ultimately impacts the Company’s business is highly uncertain and cannot be predicted with confidence at this time.

Nature of Business and Basis of Presentation

6 Months Ended

Jun. 30, 2023

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Nature of Business and Basis of Presentation

Note 1. Nature of Business and Basis of Presentation

Nature of Operations

Poseida Therapeutics, Inc. (the “Company” or “Poseida”) is a clinical-stage cell and gene therapy company advancing a new class of treatments for patients with cancer and rare diseases. The Company has discovered and is developing a broad portfolio of product candidates in a variety of indications based on its core proprietary platforms, including its non-viral piggyBac DNA Delivery System, Cas-CLOVER Site-specific Gene Editing System and nanoparticle- and AAV-based gene delivery technologies.

The Company is subject to risks and uncertainties common to development-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s therapeutic development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

Liquidity and Capital Resources

The Company has experienced net losses and negative cash flows from operations since its inception and has relied on its ability to fund its operations primarily through equity and debt financings and strategic collaborations. For the six months ended June 30, 2023, the Company incurred a net loss of $66.3 million and negative cash flows from operations of $71.3 million. The Company expects it will continue to incur net losses and negative cash flows from operations for at least the next several years. As of June 30, 2023, the Company had an accumulated deficit of $537.2 million.

The Company expects that its cash, cash equivalents and short-term investments as of June 30, 2023 of $214.6 million will be sufficient to fund its operations for at least the next twelve months from the date of issuance of these condensed consolidated financial statements. In the long term, the Company will need additional financing to support its continuing operations and pursue its business strategy. Until such time as the Company can generate significant revenue from product sales, if ever, it expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances, and licensing arrangements. The Company may be unable to raise additional funds or enter into such other agreements when needed on favorable terms or at all. The inability to raise capital as and when needed would have a negative impact on the Company’s financial condition and its ability to pursue its business strategy. The Company will need to generate significant revenue to achieve profitability, and it may never do so.

Basis of Presentation and Consolidation

The accompanying condensed consolidated financial statements reflect the Company’s financial position, results of operations and cash flows, in conformity with generally accepted accounting principles in the United States of America (“GAAP”), for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The accompanying condensed consolidated financial statements include the accounts of Poseida Therapeutics, Inc. and its wholly owned subsidiary. All intercompany transactions and balances have been eliminated. These unaudited condensed consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary to fairly state the financial position and the results of its operations and cash flows for interim periods presented. Interim-period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the Securities and Exchange Commission (“SEC”) on March 9, 2023 from which the Company derived its condensed consolidated balance sheet as of December 31, 2022.

Risk and Uncertainties

Global events such as Russia’s invasion of Ukraine and the retaliatory measures that have been taken, or could be taken in the future, by the United States, NATO, and other countries have created global security concerns that could result in a regional conflict and otherwise have a lasting impact on regional and global economies, any or all of which could disrupt the Company’s supply chain and adversely affect its ability to conduct ongoing and future clinical trials of the Company’s product candidates. The extent to which any such ongoing or future conflict ultimately impacts the Company’s business is highly uncertain and cannot be predicted with confidence at this time.

Stock-Based Compensation - Summary of the Company's Stock Option Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Balance, Shares \| shares	11,861,881
Granted, Shares \| shares	3,980,949
Exercised, Shares \| shares	(29,908)
Forfeited/Cancelled, Shares \| shares	(208,640)
Balance, Shares \| shares	15,604,282
Options vested and expected to vest as of March 31, 2023 \| shares	15,604,282
Options vested and exercisable as of March 31, 2023 \| shares	6,435,501
Balance, Weighted Average Exercise Price \| $ / shares	$ 7.61
Options Granted, Weighted Average Exercise Price \| $ / shares	4.74
Exercised, Weighted Average Exercise Price \| $ / shares	4.02
Forfeited/Cancelled, Weighted Average Exercise Price \| $ / shares	6.72
Balance, Weighted Average Exercise Price \| $ / shares	6.90
Options vested and expected to vest as of March 31, 2023 \| $ / shares	6.90
Options vested and exercisable as of March 31, 2023 \| $ / shares	$ 8.49
Balance, Weighted Average Remaining Contractual Term (Years)	8 years 2 months 19 days
Options vested and expected to vest as of March 31, 2023	8 years 2 months 19 days
Options vested and exercisable as of March 31, 2023	7 years 3 months 18 days
Balance,Aggregate Intrinsic Value \| $	$ 22
Options vested and expected to vest as of March 31, 2023 \| $	22
Options vested and exercisable as of March 31, 2023 \| $	$ 22

Composition of Certain Balance Sheet Components - Summary of Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Balance Sheet Related Disclosures [Abstract]
Contract research services	$ 10,622	$ 10,908
Payroll and related expense	6,858	11,271
Other	4,215	3,889
Total accrued expenses and other liabilities	$ 21,695	$ 26,068

Collaboration and License Agreements - Summary of Reconciliation of Closing Balance of Deferred Revenue Related to agreements (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Collaborations And License Agreement [Line Items]
Beginning balance	$ 41,056	$ 13,762
Amounts received/invoiced	17,994	157,786
Revenue recognized	(30,356)	(130,492)
Ending balance	28,694	41,056
Roche Collaboration Agreement
Collaborations And License Agreement [Line Items]
Beginning balance	31,749
Amounts received/invoiced	13,584	153,169
Revenue recognized	(16,639)	(121,420)
Ending balance	28,694	31,749
Takeda Collaboration Agreement
Collaborations And License Agreement [Line Items]
Beginning balance	9,307	13,762
Amounts received/invoiced	4,410	4,617
Revenue recognized	$ (13,717)	(9,072)
Ending balance		$ 9,307

Stock-Based Compensation

6 Months Ended

Jun. 30, 2023

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

Note 10. Stock-Based Compensation

In July 2020, the Company’s board of directors and stockholders approved and adopted the 2020 Equity Incentive Plan (the “2020 Plan”). Under the 2020 Plan, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units and other stock or cash-based awards to individuals who are current employees, officers, directors or consultants of the Company. A total of 11,183,476 shares of common stock were approved to be initially reserved for issuance under the 2020 Plan. The number of shares that remained available for issuance under the Company’s previous equity incentive plan as of the effective date of the 2020 Plan and shares subject to outstanding awards under the Company’s previous equity incentive plan as of the effective date of the 2020 Plan that are subsequently canceled, forfeited or repurchased by the Company are added to the shares reserved under the 2020 Plan. The number of shares of common stock available for issuance under the 2020 Plan is automatically increased on the first day of each calendar year during the ten-year term of the 2020 Plan, beginning with January 1, 2021 and ending with January 1, 2030,

by an amount equal to 5% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year or such lesser amount as determined by the Company’s board of directors.

In February 2022, the Company’s board of directors approved and adopted the 2022 Inducement Plan (the “Inducement Plan”). Under the Inducement Plan, the Company may grant nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards and other awards to individuals not previously employees or non-employee directors of the Company, as an inducement toward entering into employment with the Company. The maximum number of shares of common stock that may be issued under the Inducement Plan is 2,000,000 shares.

Stock Options

The following is a summary of the Company’s stock option activity for the six months ended June 30, 2023:


	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (thousands)
Balance at January 1, 2023		11,861,881		$	7.61
Granted		3,980,949			4.74
Exercised		(29,908	)		4.02
Forfeited/Cancelled		(208,640	)		6.72
Balance at June 30, 2023		15,604,282		$	6.90		8.22	$	22
Options vested and expected to vest as of June 30, 2023		15,604,282		$	6.90		8.22	$	22
Options vested and exercisable as of June 30, 2023		6,435,501		$	8.49		7.30	$	22

The weighted-average grant date fair value of options granted during the six months ended June 30, 2023 and 2022 was $3.44 and $2.72, respectively. The aggregate intrinsic value of options exercised during the six months ended June 30, 2023 and 2022 was $22 thousand and $58 thousand, respectively, determined as of the date of exercise. The Company received $0.1 million in cash from options exercised during each of the six months ended June 30, 2023 and 2022, respectively.

As of June 30, 2023, total unrecognized compensation cost related to stock options was $32.9 million, and the weighted-average period over which this cost is expected to be recognized was approximately 2.7 years.

The Company uses the Black-Scholes option pricing model to estimate the fair value of each option grant on the date of grant or any other measurement date. The assumptions that the Company used to determine the fair value of options granted to employees, non-employees and directors were as follows:


	Six Months Ended June 30,
	2023			2022
Risk-free interest rate		4.0	%		1.8	%
Expected volatility		82.6	%		81.1	%
Expected term (years)		6.0			5.8
Dividend yield		—			—

Restricted Stock Units

The following is a summary of the Company’s restricted stock unit (“RSU”) activity for the six months ended June 30, 2023:


	Shares			Weighted Average Grant Date Fair Value
Balance at January 1, 2023		2,614,402		$	3.69
Granted		2,894,592			4.81
Vested		(613,896	)		3.62
Forfeited/Cancelled		(85,846	)		4.08
Balance at June 30, 2023		4,809,252		$	4.36

RSU awards are share awards that, upon vesting, will deliver to the holder shares of the Company’s common stock. The RSUs granted to employees and non-employee directors vest up to four years from the grant date. The grant-date fair value is recognized as compensation expense over the vesting period. As of June 30, 2023, total unrecognized compensation cost related to RSUs was $18.6 million, and the weighted-average period over which this cost is expected to be recognized was approximately 3.3 years.

2020 Employee Stock Purchase Plan

In July 2020, the Company’s board of directors and stockholders approved and adopted the 2020 Employee Stock Purchase Plan (the “ESPP”), which became effective as of the pricing of the Company’s initial public offering. A total of 615,000 shares of common stock were approved to be initially reserved for issuance under the ESPP. The number of shares of common stock available for issuance under the ESPP is automatically increased on the first day of each calendar year during the first ten-years of the term of the ESPP, beginning with January 1, 2021 and ending with January 1, 2030, by an amount equal to the lessor of (i) 1% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year, (ii) 1,230,000 shares of common stock or (iii) such lesser amount as determined by the Company’s board of directors. Under the 2020 ESPP, substantially all employees can elect to have up to 15% of their annual compensation withheld to purchase up to 3,000 shares of common stock per purchase period, subject to certain limitations. The shares of common stock can be purchased over an offering period of six months and at a price of 85% of the fair market value per share of common stock on the first trading day of the applicable offering period or on the exercise date of the applicable offering period, whichever is less. Under applicable accounting guidance, the 2020 ESPP is classified as a compensatory plan. The initial purchase period commenced in March 2021. During the six months ended June 30, 2023, a total of 230,234 shares were purchased by the Company’s employees under the 2020 ESPP resulting in net proceeds of $0.6 million.

The Company uses the Black-Scholes pricing model to estimate the fair value of the purchase rights issued under the ESPP on each offering date. The assumptions that the Company used to determine the fair value of the purchase rights issued to employees during the six months ended June 30, 2023 and 2022 were as follows:


	Six Months Ended June 30,
	2023			2022
Risk-free interest rate		5.0	%		0.6	%
Expected volatility		73.2	%		84.1	%
Expected term (years)		0.5			0.5
Dividend yield		—			—

The Company recorded total stock-based compensation expense related to stock options, RSUs and the ESPP in the following expense categories of the accompanying condensed consolidated statements of operations and comprehensive income (loss) (in thousands):


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Research and development	$	3,412	$	2,646	$	6,161	$	5,074
General and administrative		2,062		2,588		6,793		5,027
Total stock-based compensation expense	$	5,474	$	5,234	$	12,954	$	10,101

Financial Instruments - (Tables)

6 Months Ended

Jun. 30, 2023

Investments Debt And Equity Securities [Abstract]

Summary of Amortized Cost and Fair Value of Securities Available-for-Sale

The following table summarizes the amortized cost and fair value of securities available-for-sale (in thousands):


	Amortized Cost/Cost		Unrealized Gains		Unrealized Losses			Fair Value
June 30, 2023:
Money market fund	$	39,483	$	—	$	—		$	39,483
U.S. government agency securities and treasuries		165,088		3		(283	)		164,808
Total	$	204,571	$	3	$	(283	)	$	204,291

December 31, 2022:
Money market fund	$	57,799	$	—	$	—		$	57,799
U.S. government agency securities and treasuries		206,520		13		(162	)		206,371
Total	$	264,319	$	13	$	(162	)	$	264,170

Fair Value Measurement

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurement

Note 5. Fair Value Measurement

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants as of the measurement date. Applicable accounting guidance provides an established hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are inputs that market participants would use in valuing the asset or liability and are developed based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the factors that market participants would use in valuing the asset or liability. There are three levels of inputs that may be used to measure fair value:

•

Level 1 — Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities

•

Level 2 — Significant other observable inputs other than Level 1 prices such as quoted prices in markets that are not active, or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability

•

Level 3 — Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity)

The Company classifies its money market funds and U.S. treasury securities, which are valued based on quoted market prices in active markets with no valuation adjustment, as Level 1 assets within the fair value hierarchy.

The following table summarizes the Company’s valuation hierarchy for its financial assets and liabilities measured at fair value on a recurring basis (in thousands):


	Level 1		Level 2		Level 3
June 30, 2023:
Assets:
Money market funds and U.S. government agency treasuries(1)	$	39,596	$	—	$	—
U.S. government agency securities and treasuries		164,695		—		—
Total	$	204,291	$	—	$	—

December 31, 2022:
Assets:
Money market funds and U.S. government agency treasuries(1)	$	63,055	$	—	$	—
U.S. government agency securities and treasuries		201,115		—		—
Total	$	264,170	$	—	$	—

(1) Included in cash and cash equivalents in the accompanying condensed consolidated balance sheets.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Net Loss Per Share - Schedule of Anti-Dilutive Securities Excluded From Computation of Diluted Net Loss per Share Attributable to Common Stockholders (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	20,724,788	15,015,753
Outstanding stock options and RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	20,413,534	14,853,494
Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	121,122	121,122
ESPP Shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	190,132	41,137

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 5,474	$ 5,234	$ 12,954	$ 10,101
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3,412	2,646	6,161	5,074
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 2,062	$ 2,588	$ 6,793	$ 5,027

Financial Instruments

6 Months Ended

Jun. 30, 2023

Investments Debt And Equity Securities [Abstract]

Financial Instruments

Note 4. Financial Instruments

The following table summarizes the amortized cost and fair value of securities available-for-sale (in thousands):


	Amortized Cost/Cost		Unrealized Gains		Unrealized Losses			Fair Value
June 30, 2023:
Money market fund	$	39,483	$	—	$	—		$	39,483
U.S. government agency securities and treasuries		165,088		3		(283	)		164,808
Total	$	204,571	$	3	$	(283	)	$	204,291

December 31, 2022:
Money market fund	$	57,799	$	—	$	—		$	57,799
U.S. government agency securities and treasuries		206,520		13		(162	)		206,371
Total	$	264,319	$	13	$	(162	)	$	264,170

No available-for-sale debt securities held as of June 30, 2023 and December 31, 2022 had remaining maturities greater than one year. At June 30, 2023, the Company did not have any securities in material unrealized loss positions.

The Company reviews its investment holdings at the end of each reporting period and evaluates any unrealized losses using the expected credit loss model to determine if the unrealized loss is a result of a credit loss or other factors. The Company also evaluates its investment holdings for impairment using a variety of factors including the Company’s intent to sell the underlying securities prior to maturity and whether it is more likely than not that the Company would be required to sell the securities before the recovery of their amortized basis. During the six months ended June 30, 2023 and 2022, the Company did not recognize any impairment or realized gains or losses on sales of investments, and the Company did not record an allowance for, or recognize, any expected credit losses.

Summary of Significant Accounting Policies - Additional Information (Details)	6 Months Ended
	Jun. 30, 2023 USD ($) Segment Customer	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)
Accounting Policies [Abstract]
Number of reportable segment \| Segment	1
Number of customer \| Customer	2
Variable lease, payments	$ 0
Description of payment terms	Payment terms on invoiced amounts are typically 30 - 60 days
Allowance for credit loss	$ 0	$ 0	$ 0

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Note 2. Summary of Significant Accounting Policies

Use of Estimates

The preparation of consolidated financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. On an ongoing basis, the Company evaluates its estimates, which include, but are not limited to, estimates related to revenue, accrued expenses, research and development expenses, stock-based compensation expense and deferred tax valuation allowances. The Company bases its estimates on historical experience and other market-specific or relevant assumptions that it believes to be reasonable under the circumstances. Actual results may differ from those estimates or assumptions.

Fair Value Measurements

Certain financial instruments are required to be recorded at fair value. Other financial instruments, like cash are recorded at cost, which approximates fair value. Cash equivalents and short-term investments are comprised of available-for-sale securities, which are carried at fair value. Additionally, carrying amounts of accounts receivable, accounts payable and accrued liabilities approximate fair value because of the short maturity of those instruments. The carrying value of the Company’s term debt approximates its fair value due to its variable interest rate, which approximates a market interest rate.

Concentration of Business Risk

The Company operates in one reportable business segment and has two customers. The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services.

Concentration of Credit Risk

Financial instruments, which potentially subject the Company to a significant concentration of credit risk, consist primarily of cash and cash equivalents and investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits and investments are held.

Leases

The Company accounts for leases in accordance with Accounting Standards Codification Topic 842, Leases, (“ASC 842”). The Company determines if an arrangement is a lease at contract inception. A lease exists when a contract conveys the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. The definition of a lease embodies two conditions: (1) there is an identified asset in the contract that is land or a depreciable asset (i.e., property, plant, and equipment), and (2) the Company has the right to control the use of the identified asset.

Operating leases where the Company is the lessee are included in operating lease right-of-use (“ROU”) assets, operating lease liabilities, current and operating lease liabilities, non-current on its condensed consolidated balance sheets. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date.

ASC 842 requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. The rates implicit in the Company’s leases are not known, therefore, the incremental borrowing rate is used based on the information available at commencement date in determining the present value of lease payments. The Company’s incremental borrowing rate for a lease is the rate of interest it would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms.

The lease term for all of the Company’s leases includes the noncancelable period of the lease. Where the Company’s lease term is impacted by options to extend or terminate the lease, when it is reasonably certain that it will exercise such option, then the lease payments are included in the measurement of the lease asset or liability.

The Company has elected not to recognize ROU assets and lease liabilities for all short-term leases that have a lease term of 12 months or less. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term. There are no variable lease payments associated with these leases. Additionally, the Company has elected to account for the lease and non-lease components together as a single lease component for its real estate asset class.

Revenue Recognition

The Company’s revenues to date have been generated primarily through collaboration and license agreements. The Company’s collaboration and license agreements may contain multiple elements including intellectual property licenses and research, and development services. Consideration the Company receives under these arrangements may include upfront payments, research and development funding, cost reimbursements, research, development, regulatory and commercial milestone payments, and royalty payments.

The Company applies Accounting Standard Codification Topic 606, Revenue from Contracts with Customers (“ASC 606”), issued by the Financial Accounting Standards Board (“FASB”) to account for its contracts with customers. Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration that the Company expects to be entitled to receive in exchange for these services. The Company analyzes the nature of these performance obligations in the context of individual collaboration and license agreements in order to assess the distinct performance obligations. The Company evaluates its contracts with customers for proper classification in the consolidated statements of operations based on the nature of the underlying activity. Transactions with customers recorded in the Company’s consolidated statements of operations are recorded on either a gross or net basis, depending on the characteristics of the collaborative relationship.

To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that it will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Company allocates the transaction price to individual performance obligations on their relative standalone selling price basis. Standalone selling prices are based on observable prices at which the Company separately sells the products or services. If a standalone selling price is not directly observable, then the Company estimates the standalone selling price considering market conditions and entity-specific factors including, but not limited to, features and functionality of the products and services.

The Company receives payments from its collaborators based on terms established in each contract. Upfront payments and other payments may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under the contract.

Accounts Receivable and Allowance for Credit Losses

Accounts receivable primarily consist of amounts due from customers for services and payments due based on contractual terms. Accounts receivable are recorded when the right to consideration becomes unconditional. For research and development services, the Company generally bills its customers monthly or quarterly as the services are performed. Payment terms on invoiced amounts are typically 30 - 60 days. The Company recognizes estimated allowance for credit losses based on an assessment of a customer’s ability to pay, credit quality of the customer, age of receivable balances and current economic conditions. As of June 30, 2023 and December 31, 2022, the Company recorded no allowance for credit losses.

Comprehensive Income (Loss)

Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on short-term investments. Comprehensive gains (losses) have been reflected in the unaudited condensed consolidated statements of operations and comprehensive income (loss) for all periods presented.

Emerging Growth Company Status

The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these condensed consolidated financial statements

may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.

Recently Adopted Accounting Pronouncements

In June 2016, the FASB issued Accounting Standard Update (“ASU”) 2016-13, Measurement of Credit Losses on Financial Instruments, which established ASC 326, Financial Instruments - Credit Losses. This ASU, along with subsequent amendments, improves financial reporting by requiring timely recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. The Company adopted ASU 2016-13 on January 1, 2023. The adoption of this standard had no impact on the Company’s condensed consolidated financial statements and disclosures.

Recently Issued Accounting Pronouncements

In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, and in January 2021, issued ASU 2021-01, Reference Rate Reform: Scope. These updates provide optional expedients and exceptions for applying US GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The optional guidance is provided to ease the potential burden of accounting for reference rate reform. The guidance is effective and could be adopted no later than December 31, 2022. In December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, to extend the temporary accounting rules under Topic 848 from December 31, 2022 to December 31, 2024. The Company is currently evaluating the impact adopting the new accounting guidance may have on the Company’s financial position and results of operations.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating Activities:
Net loss	$ (66,303)	$ (101,093)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	2,732	2,467
Non-cash loss on contract termination		5,687
Loss on disposal of property and equipment	3	205
Stock-based compensation	12,954	10,101
Accretion of discount on issued term debt	361	405
Accretion on investment securities, net	(4,244)	(97)
Changes in operating assets and liabilities:
Accounts receivable	(2,818)	(232)
Prepaid expenses and other current assets	3,207	1,017
Operating lease right-of-use assets	1,689	2,262
Other long-term assets	(10)	610
Accounts payable	(131)	(5,859)
Accrued expenses and other liabilities	(4,565)	(205)
Operating lease liabilities	(1,823)	(2,418)
Deferred revenue	(12,363)	(3,903)
Net cash used in operating activities	(71,311)	(91,053)
Investing Activities:
Purchases of property and equipment	(1,968)	(1,961)
Purchases of short-term investments	(109,374)	(79,611)
Proceeds from maturities of short-term investments	150,000
Net cash provided by (used in) investing activities	38,658	(81,572)
Financing Activities:
Proceeds from issuance of common stock under employee stock compensation plans	752	713
Payment of taxes related to net share settlement of equity awards	(494)
Proceeds from issuance of common stock through ATM offering, net of issuance costs	928
Payment of debt issuance costs		(1,450)
Proceeds from term debt		30,000
Net cash provided by financing activities	1,186	29,263
Net decrease in cash and cash equivalents	(31,467)	(143,362)
Cash and cash equivalents at beginning of period	81,378	206,325
Cash and cash equivalents at end of period	49,911	62,963
Non-cash operating, investing and financing activities:
Purchases of property and equipment in accounts payable and accrued liabilities	193	1,429
Supplemental disclosure of cash flow information:
Interest paid	$ 3,775	$ 1,996

Net Loss Per Share

6 Months Ended

Jun. 30, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

Note 12. Net Loss Per Share

Net loss per share is computed by dividing net loss attributable to common stockholders for the period by the weighted-average number of common shares outstanding during the period. Diluted loss per share reflects the additional dilution from potential issuances of common stock, such as stock issuable pursuant to the exercise of stock options and from purchases under the ESPP, as well as from the possible exercise of the outstanding warrants.

The Company’s potentially dilutive securities, which include warrants to purchase common stock and common stock options, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share.

Therefore, the weighted-average number of shares of common stock outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same.

The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:


	Six Months Ended June 30,
	2023		2022
Outstanding stock options and RSUs		20,413,534		14,853,494
Warrants to purchase common stock		121,122		121,122
ESPP Shares		190,132		41,137
		20,724,788		15,015,753

Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended		6 Months Ended
	Aug. 31, 2022	Aug. 31, 2021	Jun. 30, 2023	Dec. 31, 2022	Jul. 31, 2020
Class Of Stock [Line Items]
Common stock, shares authorized			250,000,000	250,000,000
Common stock, par value			$ 0.0001	$ 0.0001
Common stock, voting rights			Each share of common stock is entitled to one vote.
Dividends declared			$ 0
Proceeds from issuance of common stock through ATM offering, net of issuance costs			$ 928,000
Common stock issued and sold			86,878,341	85,964,161
Common Stock
Class Of Stock [Line Items]
Warrants to purchase stock			93,518
Warrants to purchase stock			$ 4.28
Sale of common stock under an underwritten public offering	23,000,000
Sale of stock, price per share	$ 3.50
Shares sold pursuant to full exercise of underwriters' option to purchase additional shares	3,000,000
Proceeds from issuance of common stock through ATM offering, net of issuance costs	$ 75,300,000
2018 and 2019 Warrants \| Common Stock
Class Of Stock [Line Items]
Warrants to purchase stock			27,604
Warrants to purchase stock			$ 7.25
IPO
Class Of Stock [Line Items]
Common stock, shares authorized					250,000,000
Common stock, par value					$ 0.0001
Undesignated preferred stock, shares authorized					10,000,000
Undesignated preferred stock, par value					$ 0.0001
At the Market Facility \| Cantor Fitzgerald & Co. \| Common Stock \| Sales Agreement
Class Of Stock [Line Items]
Proceeds from issuance of common stock through ATM offering, net of issuance costs			$ 900,000
Aggregate offering price		$ 85,000,000.0
Weighted average price per share			$ 8.04
Common stock issued and sold			119,000

Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Schedule of Company's Valuation Hierarchy of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table summarizes the Company’s valuation hierarchy for its financial assets and liabilities measured at fair value on a recurring basis (in thousands):


	Level 1		Level 2		Level 3
June 30, 2023:
Assets:
Money market funds and U.S. government agency treasuries(1)	$	39,596	$	—	$	—
U.S. government agency securities and treasuries		164,695		—		—
Total	$	204,291	$	—	$	—

December 31, 2022:
Assets:
Money market funds and U.S. government agency treasuries(1)	$	63,055	$	—	$	—
U.S. government agency securities and treasuries		201,115		—		—
Total	$	264,170	$	—	$	—

(1) Included in cash and cash equivalents in the accompanying condensed consolidated balance sheets.

Collaborations and License Agreements

6 Months Ended

Jun. 30, 2023

Collaborations And License Agreement [Line Items]

Collaboration and License Agreements

Note 7. California Institute of Regenerative Medicine Award

The Company has been awarded funding from California Institute of Regenerative Medicine (“CIRM”) to develop certain internal programs. Under the terms of the funding, both CIRM and the Company have co-funded specified programs, under which funding is provided in developmental milestones determined as a part of the award. The Company is obligated to share potential future revenues for the related programs with CIRM. The percentage of revenues due to CIRM in the future is dependent on the amount of the award received and whether revenue is generated from product sales or through license fees. The maximum revenue sharing amount the Company may be required to pay to CIRM is equal to nine times the total amount awarded and paid to the Company. As an alternative to revenue sharing, the Company has the option to convert any award to a loan, which such option the Company must exercise on or before ten business days after the FDA notifies the Company that it has accepted the Company’s application for marketing authorization. In the event the Company exercises its right to convert any award to a loan, it would be obligated to repay the loan within ten business days of making such election. Repayment amounts due to CIRM vary dependent on when the award is converted to a loan, ranging from 60% of the award granted to the full amount received plus interest at the rate of the three-month LIBOR rate plus 10% per annum. Since the Company may be required to repay some or all of the amounts awarded by CIRM, the Company accounts for this award as a liability as the Company’s intention is to convert the award into a loan. Given the uncertainty in amounts due upon repayment, the Company has recorded amounts received without any discount or interest recorded, upon determination of amounts that would become due, the Company will adjust accordingly.

In September 2018, the Company was granted an award in the amount of $4.0 million from CIRM to support the Company’s preclinical studies for its P-PSMA-101 program. The Company received the full amount of the award based on achievement of specific developmental milestones. The amount of the award is presented as a deferred CIRM grant liability in the accompanying condensed consolidated balance sheets.

Roche Ltd And Takeda Pharmaceuticals USA Inc.

Collaborations And License Agreement [Line Items]

Collaboration and License Agreements

Note 6. Collaboration and License Agreements

Roche

Terms of the Agreement

In July 2022, the Company entered into a collaboration and license agreement (the “Roche Collaboration Agreement”) with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. (collectively, “Roche”), pursuant to which the Company granted to Roche: (i) an exclusive, worldwide license under certain Company intellectual property to develop, manufacture and commercialize allogeneic CAR-T cell therapy products from each of the Company’s existing P-BCMA-ALLO1 and P-CD19CD20-ALLO1 programs (each a “Tier 1 Program”); (ii) an exclusive option to acquire an exclusive, worldwide license under certain Company intellectual property to develop, manufacture and commercialize allogeneic CAR-T cell therapy products from each of the Company’s existing P-BCMACD19-ALLO1 and P-CD70-ALLO1 programs (each, a “Tier 2 Program”); (iii) an exclusive license under certain Company intellectual property to develop, manufacture and commercialize allogeneic CAR-T cell therapy products from the up to six Collaboration Programs (as defined below) designated by Roche; (iv) an option for a non-exclusive, commercial license under certain limited Company intellectual property to develop, manufacture and commercialize certain Roche proprietary cell therapy products for up to three solid tumor targets to be identified by Roche (“Licensed Products”); and (v) the right of first offer for two (2) early-stage existing programs within hematologic malignancies. The Roche Collaboration Agreement became effective in September 2022 upon expiration of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended.

For each Tier 1 Program, the Company will perform development activities through a Phase 1 dose escalation clinical trial, and Roche is obligated to reimburse a specified percentage of certain costs incurred by the Company in its performance of such activities, up to a specified reimbursement cap for each Tier 1 Program. For each Tier 2 Program, the Company will perform research and development activities either through selection of a development candidate for IND-enabling studies or, subject to Roche’s election and payment of an option maintenance fee, through completion of a Phase 1 dose escalation clinical trial. In addition, for each Tier 2 Program for which Roche exercises its option for an exclusive license, Roche is obligated to pay an option exercise fee. For each Tier 1 Program and Tier 2 Program, the Company will perform manufacturing activities until the completion of a technology transfer to Roche.

The parties will conduct an initial two-year research program to explore and preclinically test a specified number of agreed-upon next generation therapeutic concepts relating to allogeneic CAR-T cell therapies. Subject to Roche’s election and payment of a specified fee, the parties would subsequently conduct a second research program of 18 months under which the parties would explore and preclinically test a specified number of additional agreed-upon next generation therapeutic concepts relating to allogeneic CAR-T therapies. Roche may designate up to six heme malignancy-directed, allogeneic CAR-T programs from the two research programs, for each of which the Company will perform research and development activities through selection of a development candidate for IND-enabling activities (each, a “Collaboration Program”). Upon its designation of each Collaboration Program, Roche is obligated to pay a designation fee. After the Company’s completion of lead optimization activities for a Collaboration Program, Roche may elect to transition such program to Roche with a payment to the Company or terminate it. Alternatively, Roche may elect, for a limited number of Collaboration Programs, to have the Company conduct certain additional development and manufacturing activities through the completion of a Phase 1 dose escalation clinical trial, in which case Roche will pay certain milestones and reimburse a specified

percentage of the Company’s costs incurred in connection with such development and manufacturing activities. For each Collaboration Program, the Company will perform manufacturing activities until the completion of a technology transfer to Roche.

In consideration for the rights granted to Roche under the Roche Collaboration Agreement, the Company received an upfront payment of $110.0 million. In addition, subject to Roche exercising its Tier 2 Program options, designating Collaboration Programs, and exercising its option for the Licensed Products commercial license and further contingent on, among other things, achieving specified objectives, the Company is eligible to receive up to (i) $1.5 billion in aggregate payments for Tier 1 Programs comprised of research funding, feasibility fees and $1.4 billion in development, regulatory and net sales milestones, (ii) $1.1 billion in aggregate payments for Tier 2 Programs comprised of option exercise and maintenance fees and $1.0 billion in development, regulatory and net sales milestones, (iii) $2.9 billion in aggregate payments for the Collaboration Programs comprised of certain reimbursements, fees and milestone payments; and (iv) $415.0 million in payments for the Licensed Products comprised of certain reimbursements, fees and milestone payments.

The Company is further entitled to receive, on a product-by-product basis, tiered royalty payments in the mid-single to low double digits on net sales of products from the Tier 1 Programs, optioned Tier 2 Programs and Collaboration Programs and in the low to mid-single digits for Licensed Products, in each case, subject to certain customary reductions and offsets. Royalties will be payable, on a product-by-product and country-by-country basis, until the latest of the expiration of the licensed patents covering such product in such country or ten years from first commercial sale of such product in such country.

The Roche Collaboration Agreement will continue in effect on a product-by-product and country-to-country basis until there is no remaining royalty or other payment obligations. The Roche Collaboration Agreement includes standard termination provisions, including for material breach or insolvency and for Roche’s convenience. Certain of these termination rights can be exercised with respect to a particular product or license, as well as with respect to the entire Roche Collaboration Agreement.

Revenue Recognition

At contract inception, the Company has identified six performance obligations under the Roche Collaboration Agreement: (i) licenses associated with the Tier 1 Programs, (ii) research and development efforts for the Tier 1 Programs, (iii) clinical drug supply for the Tier 1 Programs, (iv) manufacturing process development program for the Tier 1 Programs, (v) research and development efforts for the Tier 2 Programs, and (vi) research and development efforts for the Collaboration Programs. The Company concluded that Roche’s options within the Roche Collaboration Agreement do not represent material rights and are not considered performance obligations as they do not contain a significant and incremental discount. The licenses associated with the Tier 1 Programs were delivered at the beginning of the agreement term and deemed capable of being distinct as the Company concluded that Roche has the knowledge and capabilities to continue development work and fully utilize the licenses without the Company’s involvement.

In order to determine the transaction price, the Company evaluated all the payments to be received during the term of the Roche Collaboration Agreement. Certain milestones and additional fees were considered variable consideration, which were not included in the initial transaction price based on the most likely amount method. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The Company determined that the transaction price at the inception of the Roche Collaboration Agreement was $185.0 million, which consists of the upfront payment of $110.0 million, future research funding for the Tier 1 Programs of $40.0 million and a $35.0 million milestone achieved in September 2022 for the Tier 1 Programs. As of June 30, 2023, all other future potential milestone payments were excluded from the estimated total transaction price as they were considered constrained.

The performance obligation associated with the licenses for the Tier 1 Programs was satisfied as of the effective date of the Roche Collaboration Agreement. All other performance obligations will be recognized on a proportional basis as the underlying services are provided based on actual costs incurred as a percentage of total estimated costs. The Company determined that the cost-based input method most faithfully depicts the pattern in which these performance obligations are satisfied. Any cumulative effect of revisions to estimated costs to complete the Company’s performance obligation will be recorded in the period in which changes are identified and amounts can be reasonably estimated. This approach requires the Company to use significant judgment and make estimates of future expenditures. If the Company’s estimates or judgments change over the course of the collaboration, they may affect the timing and amount of revenue that it recognizes in the current and future periods.

Takeda

Terms of the Agreement

In October 2021, the Company entered into a collaboration and license agreement (the “Takeda Collaboration Agreement”) with Takeda Pharmaceuticals USA, Inc. (“Takeda”), pursuant to which the Company granted to Takeda a worldwide exclusive license under the Company’s certain platform technologies including piggyBac, Cas-CLOVER, biodegradable DNA and RNA nanoparticle delivery technology and other proprietary genetic engineering platforms to research, develop, manufacture and commercialize gene therapy products for certain indications, including Hemophilia A. The parties are collaborating to initially develop up to six in vivo gene therapy programs and Takeda also has an option to add two additional programs to the collaboration. The Company is obligated to perform research activities to the extent requested by Takeda up to the candidate selection stage, after which Takeda is obligated to assume responsibility for further development, manufacturing and commercialization of each program.

Under the Takeda Collaboration Agreement, the Company received an upfront payment of $45.0 million, of which $5.0 million represents prepaid research funding. Takeda is obligated to provide funding for all collaboration program development costs; provided that the Company is obligated to perform certain platform development activities at its own cost. Under the Takeda Collaboration Agreement, the Company is eligible to receive preclinical milestone payments that could potentially exceed $82.5 million in the aggregate if preclinical milestones for all six programs are achieved. The Company is also eligible to receive future clinical development, regulatory and commercial milestone payments of $435.0 million in the aggregate per target, with a total potential deal value over the course of the collaboration of up to $2.7 billion, if milestones for all six programs are achieved and up to $3.6 billion if the milestones related to the two optional programs are also achieved. The Company is entitled to receive tiered royalty payments on net sales in the mid-single to low double digits, subject to certain standard reductions and offsets. Royalties will be payable, on a product-by-product and country-by-country basis, until the latest of the expiration of the licensed patents covering such product in such country, ten years from first commercial sale of such product in such country, or expiration of regulatory exclusivity for such product in such country.

On May 31, 2023, the Company received written notice from Takeda of its election to terminate the Takeda Collaboration Agreement, effective July 30, 2023 (the “Termination Date”). Until the Termination Date, the parties performed their respective obligations under the Collaboration Agreement and upon the Termination Date, the Company’s exclusivity obligations under the Collaboration Agreement terminated. In addition, the licenses granted to Takeda by the Company, and the licenses granted to the Company by Takeda to perform research activities under the Collaboration Agreement terminated. The Company recognized $8.9 million of previously deferred revenue during the six months ended June 30, 2023 in acknowledgement these performance obligations are no longer required to be performed.

Revenue Recognition

The promised goods and services under the Takeda Collaboration Agreement were accounted for as following separate performance obligations: (i) development and commercialization licenses for initial two indications, (ii) separate material rights associated with four additional licenses Takeda has an option to acquire individually, (iii) platform technology enhancement services, and (iv) research and development services.

The Company recognizes revenue from platform technology enhancement services, which are delivered over time, based on the amount of incurred development expenses reimbursed by the customer as a percentage of total expected reimbursable expenses associated with the contract. As of June 30, 2023, all future potential milestone payments were excluded from the estimated total transaction price as they were considered constrained.

There are no contract assets as of June 30, 2023 or December 31, 2022 related to the Roche Collaboration Agreement or Takeda Collaboration Agreement. A reconciliation of the closing balance of deferred revenue related to the agreements is as follows (in thousands):


	Roche Collaboration Agreement			Takeda Collaboration Agreement			Total
Balance as of December 31, 2021	$	—		$	13,762		$	13,762
Amounts received/invoiced		153,169			4,617			157,786
Revenue recognized		(121,420	)		(9,072	)		(130,492	)
Balance as of December 31, 2022	$	31,749		$	9,307		$	41,056
Amounts received/invoiced		13,584			4,410			17,994
Revenue recognized		(16,639	)		(13,717	)		(30,356	)
Balance as of June 30, 2023	$	28,694		$	—		$	28,694

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues:
Collaboration revenue	$ 20,013	$ 2,700	$ 30,356	$ 4,135
Operating expenses:
Research and development	39,192	35,008	77,244	83,858
General and administrative	8,676	9,237	20,483	18,782
Total operating expenses	47,868	44,245	97,727	102,640
Loss from operations	(27,855)	(41,545)	(67,371)	(98,505)
Other income (expense):
Interest expense	(2,141)	1,543	(4,169)	(2,620)
Other income, net	2,540	52	5,237	32
Net loss	(27,456)	(43,036)	(66,303)	(101,093)
Other comprehensive expense:
Unrealized loss on short-term investments	(282)	(132)	(131)	132
Comprehensive loss	$ (27,738)	$ (43,168)	$ (66,434)	$ (101,225)
Net loss per share, basic	$ (0.32)	$ (0.69)	$ (0.77)	$ (1.61)
Net loss per share, diluted	$ (0.32)	$ (0.69)	$ (0.77)	$ (1.61)
Weighted-average number of shares outstanding, basic	86,794,697	62,713,363	86,531,422	62,635,074
Weighted-average number of shares outstanding, diluted	86,794,697	62,713,363	86,531,422	62,635,074
Collaboration Revenue
Revenues:
Collaboration revenue	$ 20,013	$ 2,700	$ 30,356	$ 4,135

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Jul. 31, 2020	Jun. 30, 2023	Jun. 30, 2022	Feb. 28, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant date fair value of options granted		$ 3.44	$ 2.72
Aggregate intrinsic value of options exercised		$ 22	$ 58
Cash received from options exercised		100	$ 100
Unrecognized compensation cost		$ 32,900
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period over which cost expected to be recognized		2 years 8 months 12 days
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period over which cost expected to be recognized		3 years 3 months 18 days
Vesting period		4 years
Unrecognized compensation cost		$ 18,600
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock reserved for issuance	11,183,476
Share-based compensation award term	10 years
Percentage increase of outstanding number of shares of common stock	5.00%
Inducement Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock issuable				2,000,000
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock reserved for issuance	615,000
Share-based compensation award term	10 years
Percentage increase of outstanding number of shares of common stock	1.00%
Share-based compensation shares issued in period	1,230,000
Offering period of common stock	six months
Percentage of the fair market value per share of common stock	85.00%
Initial purchase period, commenced	2021-03
Total shares purchased by employees		230,234
Net proceeds from share purchase by employees		$ 600
2020 Employee Stock Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of annual compensation	15.00%
Number of shares purchased	3,000

Collaborations and License Agreements (Tables)

6 Months Ended

Jun. 30, 2023

Collaborations And License Agreement [Abstract]

Summary of Reconciliation of Closing Balance of Deferred Revenue Related to agreements

A reconciliation of the closing balance of deferred revenue related to the agreements is as follows (in thousands):


	Roche Collaboration Agreement			Takeda Collaboration Agreement			Total
Balance as of December 31, 2021	$	—		$	13,762		$	13,762
Amounts received/invoiced		153,169			4,617			157,786
Revenue recognized		(121,420	)		(9,072	)		(130,492	)
Balance as of December 31, 2022	$	31,749		$	9,307		$	41,056
Amounts received/invoiced		13,584			4,410			17,994
Revenue recognized		(16,639	)		(13,717	)		(30,356	)
Balance as of June 30, 2023	$	28,694		$	—		$	28,694

Commitments and Contingencies - Additional Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) ft² Option	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Oct. 31, 2021 ft²
Commitments And Contingencies [Line Items]
Operating leases, number of square feet \| ft²	110,000
ROU asset	$ 23,396		$ 25,085
Lease liability	$ 28,679
Operating lease, number of options to extend term \| Option	2
Operating lease, extended term	5 years
Operating lease, option to extend	true
Operating lease, option to extend, description	The lease agreements include two options to extend the term for a period of 5 years each.
Operating lease expense	$ 2,900	$ 3,700
Impairment of ROU asset	600
Operating lease, payments	$ 3,200
Operating lease, weighted-average remaining lease term	6 years 1 month 6 days
Operating lease, weighted -average discount rate	8.90%
Research and Administrative Activities
Commitments And Contingencies [Line Items]
Operating leases, number of square feet \| ft²				23,000
Lease Expires on December 31, 2029
Commitments And Contingencies [Line Items]
Operating leases, number of square feet \| ft²	87,000
Laboratory and Office Space Facility
Commitments And Contingencies [Line Items]
ROU asset		4,400
Lease liability		$ 4,400

California Institute of Regenerative Medicine Award - Additional Information (Details) - CIRM $ in Millions	1 Months Ended	6 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2023 Time
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue sharing multiple \| Time		9
Period to exercise loan option upon food and drug administration authorization		10 days
Repayment period		10 days
Repayment of awards percentage		60.00%
P-PSMA-101 program
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Award received \| $	$ 4.0
LIBOR
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Debt instrument basis spread on variable rate		10.00%

Term Debt - Additional Information (Details) $ in Millions		1 Months Ended	6 Months Ended
Term Debt - Additional Information (Details) $ in Millions	Jul. 01, 2023	Feb. 28, 2022 USD ($) Months	Jun. 30, 2023 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Debt issuance costs			$ 1.6
Debt instrument final payment fee accrued			2.3
Capital stock in excess		$ 0.3
2022 Loan Agreement
Debt Instrument [Line Items]
Debt instrument maturity date		Feb. 01, 2027
2022 Loan Agreement \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument basis spread on variable rate	7.83%
Debt instrument interest rate during period	0.10%
2022 Loan Agreement \| Oxford
Debt Instrument [Line Items]
Long-term debt		$ 60.0
Long-term debt		In February 2022, the Company entered into a new Loan and Security Agreement (“2022 Loan Agreement”) with Oxford. Pursuant to the terms of the 2022 Loan Agreement, the Company borrowed $60.0 million in term loans (the “Term Loans”), of which $31.6 million was used to repay the balance outstanding under the Amended Loan Agreement, including $0.2 million of accrued interest. Under the 2022 Loan Agreement the initial interest-only period was through April 1, 2025, followed by 23 equal monthly payments of principal and applicable interest. In September 2022, a qualifying equity event, as defined in the 2022 Loan Agreement, was achieved which extended the interest-only period through April 1, 2026, followed by 11 equal monthly payments of principal and applicable interest. As a result, all amounts outstanding under the 2022 Loan Agreement will mature on February 1, 2027 (the “Maturity Date”).
Debt instrument repayment number of month \| Months		23
Debt instrument repayment additional number of monthly payments due period extension \| Months		11
Amended Loan Agreement
Debt Instrument [Line Items]
Amount used to repay outstanding debt		$ 31.6
Payment of accrued interest		0.2
Debt instrument, fee amount		$ 1.5
Debt issuance costs			1.5
Term A Loan \| Amended Loan Agreement
Debt Instrument [Line Items]
Long-term debt				$ 20.0
Term B Loan \| Amended Loan Agreement
Debt Instrument [Line Items]
Long-term debt				$ 10.0
Term Loans
Debt Instrument [Line Items]
Long-term debt			$ 60.0
Debt instrument basis spread on variable rate			13.02%
Interest rate recognized under effective interest method			14.51%
Term Loans \| 2022 Loan Agreement
Debt Instrument [Line Items]
Debt instrument basis spread on variable rate		7.83%
Debt instrument floating per annum rate		30-day U.S. Dollar (USD) LIBOR
Debt instrument interest rate during period		0.11%
Debt instrument, final payment fee percentage		7.50%
Repayment of outstanding debt		$ 5.0
Term Loans \| 2022 Loan Agreement \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument basis spread on variable rate	7.94%
Debt instrument floating per annum rate	1-Month CME Term Secured Overnight Financing Rate (“SOFR”)
Term Loans \| 2022 Loan Agreement \| Loan Prepayment
Debt Instrument [Line Items]
Debt instrument, final payment fee percentage		1.00%
Debt instrument term loan prepaid Period description		on or prior to February 22, 2024

Composition of Certain Balance Sheet Components - Summary of Property and Equipment Net (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Total property and equipment	$ 37,206	$ 35,062
Less: Accumulated depreciation and amortization	(16,195)	(13,476)
Total property and equipment, net	21,011	21,586
Laboratory Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	20,433	18,551
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	14,103	14,006
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Total property and equipment	1,577	1,504
Furniture, Fixtures and Other
Property Plant And Equipment [Line Items]
Total property and equipment	$ 1,093	$ 1,001

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2023

Earnings Per Share [Abstract]

Schedule of Anti-Dilutive Securities Excluded From Computation of Diluted Net Loss per Share Attributable to Common Stockholders


	Six Months Ended June 30,
	2023		2022
Outstanding stock options and RSUs		20,413,534		14,853,494
Warrants to purchase common stock		121,122		121,122
ESPP Shares		190,132		41,137
		20,724,788		15,015,753

Financial Instruments - Additional Information (Details) - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Investments Debt And Equity Securities [Abstract]
Debt securities, available-for-sale, noncurrent	$ 0		$ 0
Debt securities, available-for-sale, unrealized loss position	0
Short-term investments	164,695,000		201,115,000
Gain (loss) on sale of investments	0	$ 0
Allowance for credit loss	$ 0	$ 0	$ 0

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 49,911	$ 81,378
Short-term investments	164,695	201,115
Accounts receivable	11,906	9,088
Prepaid expenses and other current assets	3,683	6,982
Total current assets	230,195	298,563
Property and equipment, net	21,011	21,586
Operating lease right-of-use assets	23,396	25,085
Intangible assets	1,320	1,320
Goodwill	4,228	4,228
Other long-term assets	1,065	1,055
Total assets	281,215	351,837
Current liabilities:
Accounts payable	2,097	2,228
Accrued expenses and other liabilities	21,695	26,068
Operating lease liabilities, current	5,863	5,866
Deferred revenue, current	20,233	19,723
Total current liabilities	49,888	53,885
Term debt	58,402	58,250
Operating lease liabilities, non-current	22,816	24,636
Deferred CIRM grant liability	3,992	3,992
Deferred revenue, noncurrent	8,461	21,333
Other long-term liabilities	2,355	2,146
Total liabilities	145,914	164,242
Commitments and Contingencies (Note 11)
Stockholders’ equity:
Common stock, $0.0001 par value: 250,000,000 shares authorized at June 30, 2023 and December 31, 2022; 86,878,341 and 85,964,161 shares issued and outstanding as of June 30, 2023 and December 31, 2022, respectively	9	9
Additional paid-in capital	672,736	658,596
Accumulated other comprehensive loss	(280)	(149)
Accumulated deficit	(537,164)	(470,861)
Total stockholders’ equity	135,301	187,595
Total liabilities and stockholders’ equity	$ 281,215	$ 351,837

California Institute of Regenerative Medicine Award

6 Months Ended

Jun. 30, 2023

Collaborative Arrangement [Abstract]

Collaboration and License Agreements

Note 7. California Institute of Regenerative Medicine Award

Subsequent Event - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	6 Months Ended
	Aug. 04, 2023	Aug. 31, 2022	Jun. 30, 2023
Subsequent Event [Line Items]
Aggregate gross proceeds			$ 928
Common Stock
Subsequent Event [Line Items]
Sale of stock, number of shares issued		23,000,000
Sale of stock, price per share		$ 3.50
Aggregate gross proceeds		$ 75,300
Subsequent Event \| Securities Purchase Agreement \| Astellas \| Private Placement \| Common Stock
Subsequent Event [Line Items]
Sale of stock, number of shares issued	8,333,333
Sale of stock, price per share	$ 3.00
Aggregate gross proceeds	$ 25,000
Subsequent Event \| Strategic Rights Letter Agreement \| Astellas
Subsequent Event [Line Items]
Proceeds from rights granted	$ 25,000
Maximum number of shares owned at time of termination	8,000,000

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2023
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Poseida Therapeutics, Inc. (the “Company” or “Poseida”) is a clinical-stage cell and gene therapy company advancing a new class of treatments for patients with cancer and rare diseases. The Company has discovered and is developing a broad portfolio of product candidates in a variety of indications based on its core proprietary platforms, including its non-viral piggyBac DNA Delivery System, Cas-CLOVER Site-specific Gene Editing System and nanoparticle- and AAV-based gene delivery technologies. The Company is subject to risks and uncertainties common to development-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s therapeutic development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying condensed consolidated financial statements reflect the Company’s financial position, results of operations and cash flows, in conformity with generally accepted accounting principles in the United States of America (“GAAP”), for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The accompanying condensed consolidated financial statements include the accounts of Poseida Therapeutics, Inc. and its wholly owned subsidiary. All intercompany transactions and balances have been eliminated. These unaudited condensed consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary to fairly state the financial position and the results of its operations and cash flows for interim periods presented. Interim-period results are not necessarily indicative of results of operations or cash flows for a full year or any subsequent interim period. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the Securities and Exchange Commission (“SEC”) on March 9, 2023 from which the Company derived its condensed consolidated balance sheet as of December 31, 2022.
Risk and Uncertainties	Risk and Uncertainties Global events such as Russia’s invasion of Ukraine and the retaliatory measures that have been taken, or could be taken in the future, by the United States, NATO, and other countries have created global security concerns that could result in a regional conflict and otherwise have a lasting impact on regional and global economies, any or all of which could disrupt the Company’s supply chain and adversely affect its ability to conduct ongoing and future clinical trials of the Company’s product candidates. The extent to which any such ongoing or future conflict ultimately impacts the Company’s business is highly uncertain and cannot be predicted with confidence at this time.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. On an ongoing basis, the Company evaluates its estimates, which include, but are not limited to, estimates related to revenue, accrued expenses, research and development expenses, stock-based compensation expense and deferred tax valuation allowances. The Company bases its estimates on historical experience and other market-specific or relevant assumptions that it believes to be reasonable under the circumstances. Actual results may differ from those estimates or assumptions.
Fair Value Measurements	Fair Value Measurements Certain financial instruments are required to be recorded at fair value. Other financial instruments, like cash are recorded at cost, which approximates fair value. Cash equivalents and short-term investments are comprised of available-for-sale securities, which are carried at fair value. Additionally, carrying amounts of accounts receivable, accounts payable and accrued liabilities approximate fair value because of the short maturity of those instruments. The carrying value of the Company’s term debt approximates its fair value due to its variable interest rate, which approximates a market interest rate.
Concentration of Business Risk	Concentration of Business Risk The Company operates in one reportable business segment and has two customers. The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments, which potentially subject the Company to a significant concentration of credit risk, consist primarily of cash and cash equivalents and investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits and investments are held.
Leases	Leases The Company accounts for leases in accordance with Accounting Standards Codification Topic 842, Leases, (“ASC 842”). The Company determines if an arrangement is a lease at contract inception. A lease exists when a contract conveys the right to control the use of identified property, plant, or equipment for a period of time in exchange for consideration. The definition of a lease embodies two conditions: (1) there is an identified asset in the contract that is land or a depreciable asset (i.e., property, plant, and equipment), and (2) the Company has the right to control the use of the identified asset. Operating leases where the Company is the lessee are included in operating lease right-of-use (“ROU”) assets, operating lease liabilities, current and operating lease liabilities, non-current on its condensed consolidated balance sheets. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date. ASC 842 requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. The rates implicit in the Company’s leases are not known, therefore, the incremental borrowing rate is used based on the information available at commencement date in determining the present value of lease payments. The Company’s incremental borrowing rate for a lease is the rate of interest it would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. The lease term for all of the Company’s leases includes the noncancelable period of the lease. Where the Company’s lease term is impacted by options to extend or terminate the lease, when it is reasonably certain that it will exercise such option, then the lease payments are included in the measurement of the lease asset or liability. The Company has elected not to recognize ROU assets and lease liabilities for all short-term leases that have a lease term of 12 months or less. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term. There are no variable lease payments associated with these leases. Additionally, the Company has elected to account for the lease and non-lease components together as a single lease component for its real estate asset class.
Revenue Recognition	Revenue Recognition The Company’s revenues to date have been generated primarily through collaboration and license agreements. The Company’s collaboration and license agreements may contain multiple elements including intellectual property licenses and research, and development services. Consideration the Company receives under these arrangements may include upfront payments, research and development funding, cost reimbursements, research, development, regulatory and commercial milestone payments, and royalty payments. The Company applies Accounting Standard Codification Topic 606, Revenue from Contracts with Customers (“ASC 606”), issued by the Financial Accounting Standards Board (“FASB”) to account for its contracts with customers. Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration that the Company expects to be entitled to receive in exchange for these services. The Company analyzes the nature of these performance obligations in the context of individual collaboration and license agreements in order to assess the distinct performance obligations. The Company evaluates its contracts with customers for proper classification in the consolidated statements of operations based on the nature of the underlying activity. Transactions with customers recorded in the Company’s consolidated statements of operations are recorded on either a gross or net basis, depending on the characteristics of the collaborative relationship. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that it will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Company allocates the transaction price to individual performance obligations on their relative standalone selling price basis. Standalone selling prices are based on observable prices at which the Company separately sells the products or services. If a standalone selling price is not directly observable, then the Company estimates the standalone selling price considering market conditions and entity-specific factors including, but not limited to, features and functionality of the products and services. The Company receives payments from its collaborators based on terms established in each contract. Upfront payments and other payments may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under the contract.
Accounts Receivable and Allowance for Credit Losses	Accounts Receivable and Allowance for Credit Losses Accounts receivable primarily consist of amounts due from customers for services and payments due based on contractual terms. Accounts receivable are recorded when the right to consideration becomes unconditional. For research and development services, the Company generally bills its customers monthly or quarterly as the services are performed. Payment terms on invoiced amounts are typically 30 - 60 days. The Company recognizes estimated allowance for credit losses based on an assessment of a customer’s ability to pay, credit quality of the customer, age of receivable balances and current economic conditions. As of June 30, 2023 and December 31, 2022, the Company recorded no allowance for credit losses.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on short-term investments. Comprehensive gains (losses) have been reflected in the unaudited condensed consolidated statements of operations and comprehensive income (loss) for all periods presented.
Emerging Growth Company Status	Emerging Growth Company Status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these condensed consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In June 2016, the FASB issued Accounting Standard Update (“ASU”) 2016-13, Measurement of Credit Losses on Financial Instruments, which established ASC 326, Financial Instruments - Credit Losses. This ASU, along with subsequent amendments, improves financial reporting by requiring timely recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. The Company adopted ASU 2016-13 on January 1, 2023. The adoption of this standard had no impact on the Company’s condensed consolidated financial statements and disclosures. Recently Issued Accounting Pronouncements In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, and in January 2021, issued ASU 2021-01, Reference Rate Reform: Scope. These updates provide optional expedients and exceptions for applying US GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The optional guidance is provided to ease the potential burden of accounting for reference rate reform. The guidance is effective and could be adopted no later than December 31, 2022. In December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, to extend the temporary accounting rules under Topic 848 from December 31, 2022 to December 31, 2024. The Company is currently evaluating the impact adopting the new accounting guidance may have on the Company’s financial position and results of operations.

Stock-Based Compensation - Schedule of Assumptions Used to Determine the Fair Value of Purchase Rights Issued Under ESPP (Details)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	4.00%	1.80%
Expected volatility	82.60%	81.10%
Expected term (years)	6 years	5 years 9 months 18 days
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	5.00%	0.60%
Expected volatility	73.20%	84.10%
Expected term (years)	6 months	6 months

Nature of Business and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Net loss	$ 27,456	$ 38,847	$ 43,036	$ 58,057	$ 66,303	$ 101,093
Net cash used in operating activities					71,311	$ 91,053
Accumulated deficit	537,164				537,164		$ 470,861
Cash, cash equivalents and short-term investments	$ 214,600				$ 214,600

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Stock-Based Compensation - Schedule of Assumptions Used to Determine the Fair Value of Options Granted (Details)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	4.00%	1.80%
Expected volatility	82.60%	81.10%
Expected term (years)	6 years	5 years 9 months 18 days

Stockholders' Equity

6 Months Ended

Jun. 30, 2023

Equity [Abstract]

Stockholders' Equity

Note 9. Stockholders’ Equity

Authorized Shares

In connection with the completion of the Company’s initial public offering in July 2020, the Company amended its certificate of incorporation to authorize 250,000,000 shares of common stock, par value $0.0001 per share, and 10,000,000 shares of undesignated preferred stock, par value $0.0001 per share, that may be issued from time to time by the Company’s board of directors in one or more series. Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Company’s board of directors. Since the Company’s inception, there have been no dividends declared.

Warrants

Pursuant to the Amended Loan Agreement, the Company issued Oxford (i) in 2017, a warrant to purchase 93,518 shares of common stock at an exercise price of $4.28 per share, which will expire in 2027 unless earlier exercised and (ii) in 2018 and 2019, warrants to purchase an aggregate of 27,604 shares of common stock at an exercise price of $7.25 per share, which will expire in 2028 and 2029, respectively, unless earlier exercised.

Sale of Common Stock

In August 2022, the Company completed the sale of an aggregate of 23,000,000 shares of its common stock in an underwritten public offering, at a price of $3.50 per share, including 3,000,000 shares sold pursuant to the full exercise of the underwriters' option to purchase additional shares. The net proceeds to the Company from the offering were approximately $75.3 million after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company.

At the Market Facility

In August 2021, the Company entered into a Controlled Equity OfferingSM Sales Agreement (the “Sales Agreement”) with Cantor Fitzgerald & Co. (“Cantor”) to sell shares of common stock, from time to time, through an “at the market offering” program having an aggregate offering price of up to $85.0 million through which Cantor would act as sales agent. During the six months ended June 30, 2023, the Company issued and sold an aggregate of 119,000 shares of common stock at a weighted average price of $8.04 per share for net proceeds of approximately $0.9 million.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 16
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

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-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

+ Details

Stock-Based Compensation - Summary of Restricted Stock Unit (RSU) Activity (Details) - Restricted Stock Units (RSUs)	6 Months Ended
	Jun. 30, 2023 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Balance, Shares \| shares	2,614,402
Granted, Shares \| shares	2,894,592
Vested, Shares \| shares	(613,896)
Forfeited/Cancelled, Shares \| shares	(85,846)
Balance, Shares \| shares	4,809,252
Balance, Weighted Average Grant Date Fair Value \| $ / shares	$ 3.69
Granted, Weighted Average Grant Date Fair Value \| $ / shares	4.81
Vested, Weighted Average Grant Date Fair Value \| $ / shares	3.62
Forfeited/Cancelled, Weighted Average Grant Date Fair Value \| $ / shares	4.08
Balance, Weighted Average Grant Date Fair Value \| $ / shares	$ 4.36

Collaborations and License Agreements - Additional Information (Details) $ in Millions	1 Months Ended
	Jul. 31, 2022 USD ($) Program PerformanceObligation	Oct. 31, 2021 USD ($) Program	Jun. 30, 2023 USD ($)
Collaborations And License Agreement [Line Items]
Deferred revenue recognized			$ 8.9
Roche Collaboration Agreement
Collaborations And License Agreement [Line Items]
Number of collaboration programs \| Program	6
Number of early-stage existing programs \| Program	2
Research collaboration period	2 years
Research collaboration extension period	18 months
Upfront cash payment from collaboration agreement	$ 110.0
Collaboration revenue receivable terms	10 years
Number of performance obligations \| PerformanceObligation	6
Roche Collaboration Agreement \| Roche Ltd
Collaborations And License Agreement [Line Items]
Upfront cash payment from collaboration agreement	$ 110.0
Transaction price	185.0
Roche Collaboration Agreement \| Tier 1 Programs
Collaborations And License Agreement [Line Items]
Fees and milestone payments receivable	1,500.0
Development, regulatory and net sales milestones	1,400.0
Roche Collaboration Agreement \| Tier 1 Programs \| Roche Ltd
Collaborations And License Agreement [Line Items]
Future research funding	40.0
Milestone payments	35.0
Roche Collaboration Agreement \| Tier 2 Programs
Collaborations And License Agreement [Line Items]
Fees and milestone payments receivable	1,100.0
Development, regulatory and net sales milestones	1,000.0
Roche Collaboration Agreement \| Collaboration Programs
Collaborations And License Agreement [Line Items]
Fees and milestone payments receivable	2,900.0
Roche Collaboration Agreement \| Licensed Products
Collaborations And License Agreement [Line Items]
Fees and milestone payments receivable	$ 415.0
Collaborative Arrangement \| Takeda Pharmaceuticals U S A Inc
Collaborations And License Agreement [Line Items]
Upfront cash payment from collaboration agreement		$ 45.0
Collaboration revenue receivable terms		10 years
Number of initially developing gene therapy programs \| Program		6
Number of option to add additional gene therapy programs \| Program		2
Prepaid research funding		$ 5.0
Minimum upfront and preclinical milestone payments receivable		82.5
Maximum clinical development, regulatory and commercial milestone payments receivable		435.0
Collaborative Arrangement \| Takeda Pharmaceuticals U S A Inc \| Minimum
Collaborations And License Agreement [Line Items]
Collaboration agreement revenue receivable		2,700.0
Collaborative Arrangement \| Takeda Pharmaceuticals U S A Inc \| Maximum
Collaborations And License Agreement [Line Items]
Collaboration agreement revenue receivable		$ 3,600.0

Composition of Certain Balance Sheet Components

6 Months Ended

Jun. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Composition of Certain Balance Sheet Components

Note 3. Composition of Certain Balance Sheet Components

Property and equipment, net

Property and equipment, net consisted of the following (in thousands):


	June 30, 2023			December 31, 2022
Laboratory equipment	$	20,433		$	18,551
Leasehold improvements		14,103			14,006
Computer equipment and software		1,577			1,504
Furniture, fixtures and other		1,093			1,001
Total property and equipment		37,206			35,062
Less: Accumulated depreciation and amortization		(16,195	)		(13,476	)
Total property and equipment, net	$	21,011		$	21,586

Depreciation and amortization expense associated with property and equipment was $1.4 million and $2.7 million for the three and six months ended June 30, 2023, respectively and $1.3 million and $2.5 million for the three and six months ended June 30, 2022, respectively.

Accrued expenses and other liabilities

Accrued expenses and other liabilities consisted of the following (in thousands):


	June 30, 2023		December 31, 2022
Contract research services	$	10,622	$	10,908
Payroll and related expense		6,858		11,271
Other		4,215		3,889
Total accrued expenses and other liabilities	$	21,695	$	26,068

Composition of Certain Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Summary of Property and Equipment Net

Property and equipment, net consisted of the following (in thousands):


	June 30, 2023			December 31, 2022
Laboratory equipment	$	20,433		$	18,551
Leasehold improvements		14,103			14,006
Computer equipment and software		1,577			1,504
Furniture, fixtures and other		1,093			1,001
Total property and equipment		37,206			35,062
Less: Accumulated depreciation and amortization		(16,195	)		(13,476	)
Total property and equipment, net	$	21,011		$	21,586

Summary of Accrued Expenses and Other Liabilities

Accrued expenses and other liabilities consisted of the following (in thousands):


	June 30, 2023		December 31, 2022
Contract research services	$	10,622	$	10,908
Payroll and related expense		6,858		11,271
Other		4,215		3,889
Total accrued expenses and other liabilities	$	21,695	$	26,068

Fair Value Measurement - Schedule of Company's Valuation Hierarchy of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets:
Cash and cash equivalents	$ 49,911	$ 81,378
Recurring Basis \| Level 1
Assets:
Total	204,291	264,170
Recurring Basis \| Level 1 \| U.S. government agency securities and treasuries
Assets:
Total	164,695	201,115
Recurring Basis \| Level 1 \| Money Market Funds and U.S. Government Agency Treasuries
Assets:
Cash and cash equivalents	$ 39,596	$ 63,055

Subsequent Events

6 Months Ended

Jun. 30, 2023

Subsequent Events [Abstract]

Subsequent Events

Note 13. Subsequent Event

Astellas Transaction

Securities Purchase Agreement

On August 4, 2023 (the “Signing Date”), the Company entered into a securities purchase agreement with Astellas US, LLC, a Delaware limited liability company (“Astellas”), pursuant to which the Company agreed to issue and sell to Astellas in a private placement (the “Private Placement”) an aggregate of 8,333,333 shares (the “Shares”) of common stock at a purchase price of $3.00 per Share, for aggregate gross proceeds of approximately $25.0 million. The Private Placement closed on August 7, 2023 (the “Closing Date”).

Registration Rights Agreement

On the Signing Date, the Company also entered into a registration rights agreement with Astellas, pursuant to which the Company agreed to register the resale by Astellas of the Shares. Under the registration rights agreement, the Company has agreed to file a registration statement covering the resale of the Shares no later than the 250th day after the Closing Date.

Strategic Rights Letter Agreement

On the Signing Date, the Company also entered into a Strategic Rights Letter Agreement (the “Strategic Rights Letter”) with Astellas. Pursuant to the Strategic Rights Letter, the Company granted Astellas the right to designate a representative to attend meetings of the Company’s board of directors as an observer, as well as certain strategic rights, including a right of exclusive negotiation and first refusal to license P-MUC1C-ALLO1 (a “Program Transaction”) and notification rights for certain change in control proposals the Company may receive.

As partial consideration for the rights granted to Astellas under the Strategic Rights Letter, Astellas paid the Company a one-time payment in the amount of $25.0 million. In connection a change in control transaction or Program Transaction between the Company and Astellas, some, all or none of the one-time payment may be offset against payments owed by Astellas to the Company, dependent on certain factors set forth in the Strategic Rights Letter.

This Strategic Rights Letter shall terminate upon the earliest to occur of (i) the 18-month anniversary of the Closing Date, (ii) such time that Astellas owns fewer than 8,000,000 shares of common stock and (iii) the consummation of a change in control.

Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2023

Commitments And Contingencies Disclosure [Abstract]

Summary of Maturities of Lease Liabilities

As of June 30, 2023, maturities of lease liabilities were as follows (in thousands):


Year ending December 31,
2023 (remaining 6 months)	$	3,030
2024		6,188
2025		6,374
2026		5,107
2027		5,260
Thereafter		11,000
Total future lease payments		36,959
Imputed interest		(8,280	)
Total lease liability balance		28,679
Less current portion of lease liability		5,863
Lease liability, net of current portion	$	22,816

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2021	$ 156,211	$ 6	$ 563,064	$ 0	$ (406,859)
Beginning balance, Shares at Dec. 31, 2021		62,523,596
Issuance of common stock under employee stock compensation plans	681		681
Issuance of common stock under employee stock compensation plans, Shares		181,130
Stock-based compensation expense	4,867		4,867
Net loss	(58,057)				(58,057)
Ending balance at Mar. 31, 2022	103,702	$ 6	568,612	0	(464,916)
Ending balance, Shares at Mar. 31, 2022		62,704,726
Beginning balance at Dec. 31, 2021	156,211	$ 6	563,064	0	(406,859)
Beginning balance, Shares at Dec. 31, 2021		62,523,596
Unrealized gain on available-for-sale investments	132
Net loss	(101,093)
Ending balance at Jun. 30, 2022	65,800	$ 6	573,878	(132)	(507,952)
Ending balance, Shares at Jun. 30, 2022		62,728,726
Beginning balance at Mar. 31, 2022	103,702	$ 6	568,612	0	(464,916)
Beginning balance, Shares at Mar. 31, 2022		62,704,726
Issuance of common stock under employee stock compensation plans	32		32
Issuance of common stock under employee stock compensation plans, Shares		24,000
Stock-based compensation expense	5,234		5,234
Unrealized gain on available-for-sale investments	(132)			(132)
Net loss	(43,036)				(43,036)
Ending balance at Jun. 30, 2022	65,800	$ 6	573,878	(132)	(507,952)
Ending balance, Shares at Jun. 30, 2022		62,728,726
Beginning balance at Dec. 31, 2022	187,595	$ 9	658,596	(149)	(470,861)
Beginning balance, Shares at Dec. 31, 2022		85,964,161
Issuance of common stock under employee stock compensation plans	258		258
Issuance of common stock under employee stock compensation plans, Shares		675,726
Issuance of common stock through ATM offering, net of issuance cost	928		928
Issuance of common stock through ATM offering, net of issuance cost, Shares		119,000
Stock-based compensation expense	7,480		7,480
Unrealized gain on available-for-sale investments	151			151
Net loss	(38,847)				(38,847)
Ending balance at Mar. 31, 2023	157,565	$ 9	667,262	2	(509,708)
Ending balance, Shares at Mar. 31, 2023		86,758,887
Beginning balance at Dec. 31, 2022	187,595	$ 9	658,596	(149)	(470,861)
Beginning balance, Shares at Dec. 31, 2022		85,964,161
Unrealized gain on available-for-sale investments	(131)
Net loss	(66,303)
Ending balance at Jun. 30, 2023	135,301	$ 9	672,736	(280)	(537,164)
Ending balance, Shares at Jun. 30, 2023		86,878,341
Beginning balance at Mar. 31, 2023	157,565	$ 9	667,262	2	(509,708)
Beginning balance, Shares at Mar. 31, 2023		86,758,887
Issuance of common stock under employee stock compensation plans, Shares		119,454
Stock-based compensation expense	5,474		5,474
Unrealized gain on available-for-sale investments	(282)			(282)
Net loss	(27,456)				(27,456)
Ending balance at Jun. 30, 2023	$ 135,301	$ 9	$ 672,736	$ (280)	$ (537,164)
Ending balance, Shares at Jun. 30, 2023		86,878,341

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of the Company's Stock Option Activity

The following is a summary of the Company’s stock option activity for the six months ended June 30, 2023:


	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (thousands)
Balance at January 1, 2023		11,861,881		$	7.61
Granted		3,980,949			4.74
Exercised		(29,908	)		4.02
Forfeited/Cancelled		(208,640	)		6.72
Balance at June 30, 2023		15,604,282		$	6.90		8.22	$	22
Options vested and expected to vest as of June 30, 2023		15,604,282		$	6.90		8.22	$	22
Options vested and exercisable as of June 30, 2023		6,435,501		$	8.49		7.30	$	22

Schedule of Assumptions Used to Determine the Fair Value of Options Granted


	Six Months Ended June 30,
	2023			2022
Risk-free interest rate		4.0	%		1.8	%
Expected volatility		82.6	%		81.1	%
Expected term (years)		6.0			5.8
Dividend yield		—			—

Summary of Restricted Stock Unit (RSU) Activity

The following is a summary of the Company’s restricted stock unit (“RSU”) activity for the six months ended June 30, 2023:


	Shares			Weighted Average Grant Date Fair Value
Balance at January 1, 2023		2,614,402		$	3.69
Granted		2,894,592			4.81
Vested		(613,896	)		3.62
Forfeited/Cancelled		(85,846	)		4.08
Balance at June 30, 2023		4,809,252		$	4.36

Schedule of Assumptions Used to Determine the Fair Value of Purchase Rights Issued Under ESPP

The assumptions that the Company used to determine the fair value of the purchase rights issued to employees during the six months ended June 30, 2023 and 2022 were as follows:


	Six Months Ended June 30,
	2023			2022
Risk-free interest rate		5.0	%		0.6	%
Expected volatility		73.2	%		84.1	%
Expected term (years)		0.5			0.5
Dividend yield		—			—

Schedule of Stock-Based Compensation Expense


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Research and development	$	3,412	$	2,646	$	6,161	$	5,074
General and administrative		2,062		2,588		6,793		5,027
Total stock-based compensation expense	$	5,474	$	5,234	$	12,954	$	10,101

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2023	Aug. 04, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Trading Symbol	PSTX
Entity Registrant Name	Poseida Therapeutics, Inc.
Entity Central Index Key	0001661460
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Security12b Title	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity File Number	001-39376
Entity Incorporation State Country Code	DE
Entity Tax Identification Number	47-2846548
Entity Address, Address Line One	9390 Towne Centre Drive
Entity Address, Address Line Two	Suite 200
Entity Address City Or Town	San Diego
Entity Address State Or Province	CA
Entity Address Postal Zip Code	92121
City Area Code	858
Local Phone Number	779-3100
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		86,916,199

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	86,878,341	85,964,161
Common stock, shares outstanding	86,878,341	85,964,161

Financial Instruments - Summary of Amortized Cost and Fair Value of Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost/Cost	$ 204,571	$ 264,319
Available-for-Sale Securities, Unrealized Gains	3	13
Available-for-Sale Securities , Unrealized Losses	(283)	(162)
Available-for-Sale Securities, Fair Value	204,291	264,170
Money Market Fund
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost/Cost	39,483	57,799
Available-for-Sale Securities, Fair Value	39,483	57,799
U.S. Government Agency Securities and Treasuries
Schedule Of Available For Sale Securities [Line Items]
Available-for-Sale Securities, Amortized Cost/Cost	165,088	206,520
Available-for-Sale Securities, Unrealized Gains	3	13
Available-for-Sale Securities , Unrealized Losses	(283)	(162)
Available-for-Sale Securities, Fair Value	$ 164,808	$ 206,371

Commitments and Contingencies - Summary of Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Commitments And Contingencies Disclosure [Abstract]
2023 (remaining 9 months)	$ 3,030
2024	6,188
2025	6,374
2026	5,107
2027	5,260
Thereafter	11,000
Total future lease payments	36,959
Imputed interest	(8,280)
Total lease liability balance	28,679
Less current portion of lease liability	5,863	$ 5,866
Lease liability, net of current portion	$ 22,816	$ 24,636

Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 11. Commitments and Contingencies

Operating Leases

As of June 30, 2023, the Company had operating leases consisting of approximately 110,000 square feet of manufacturing, laboratory and office space in San Diego, California, including 87,000 square feet under a lease that expires on December 31, 2029, which contains a pilot manufacturing facility adjacent to office and laboratory space. The lease agreements include two options to extend the term for a period of 5 years each.

In October 2021, the Company entered into a sublease agreement for a facility in San Diego, California consisting of approximately 23,000 square feet to be used for research and administrative activities. The lease term commenced in March 2022 and will expire on December 31, 2025. During the six months ended June 30, 2022, the Company recorded an ROU asset of $4.4 million and a corresponding lease liability related to this sublease.

During the six months ended June 30, 2023 and 2022, the Company recognized $2.9 million and $3.7 million, respectively, of operating lease expense, including a $0.6 million impairment of an ROU asset during the six months ended June 30, 2022. During the six months ended June 30, 2023, the Company paid $3.2 million for its operating leases. As of June 30, 2023, the weighted-average remaining lease term and weighted-average discount rate for operating leases were 6.1 years and 8.9%, respectively.

As of June 30, 2023, maturities of lease liabilities were as follows (in thousands):


Year ending December 31,
2023 (remaining 6 months)	$	3,030
2024		6,188
2025		6,374
2026		5,107
2027		5,260
Thereafter		11,000
Total future lease payments		36,959
Imputed interest		(8,280	)
Total lease liability balance		28,679
Less current portion of lease liability		5,863
Lease liability, net of current portion	$	22,816

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, contract research organizations, business partners and other parties with respect to certain matters including, but not limited to, losses arising from breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and certain of its executive officers that require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims.

Legal Contingencies

In the ordinary course of business, the Company may face claims brought by third parties against the Company. The Company believes that there are currently no lawsuits, threats of litigation, or asserted or unasserted claims pending that could, individually or in the aggregate, have a material adverse effect on the Company’s results of operations or financial condition.