0000950170-24-057805 | 10-Q | XBRL Viewer

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Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) Tranche $ / shares shares	Mar. 31, 2024 USD ($) shares	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) shares	Mar. 01, 2023 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share based compensation expense		$ 21,600	$ 15,200
Proceeds from issuance of common stock related to at-the-market offering, net of issuance costs		93,640	$ 0
Unamortized/unrecognized stock-based compensation expense related to PSUs	$ 11,100	$ 11,100
Cantor [Member] \| Amended ATM Facility [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock under at-the-market offering, net of issuance costs, shares \| shares	1,237,460	1,237,460		5,016,170
Proceeds from issuance of common stock related to at-the-market offering, net of issuance costs		$ 93,600		$ 164,200
Maximum offering price of common stock under At The Market agreement					$ 300,000
Maximum percentage commission to be paid on gross proceedings under at the market agreement					3.00%
2004 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term to grant nonstatutory stock options and incentive stock options		10 years
Option grant prices as percentage of the fair market value of the common stock		100.00%
Percentage of options grant to new employees		25.00%
Shares available for grant \| shares	5,600,000	5,600,000
2004 Plan [Member] \| New Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting right		Options granted to new employees generally vest 25% after one year and monthly thereafter over a period of four years
Period from percentage of stock option vested		1 year
Vesting period		4 years
2004 Plan [Member] \| Existing Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting right		Options granted to existing employees generally vest monthly over a period of four years
Vesting period		4 years
Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant \| shares	359,992	359,992
Per unit weighted average grant date fair value \| $ / shares	$ 63.75
Number of tranche \| Tranche	2
Allocated share based compensation expense		$ 400
Performance Stock Units [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share based payment award award vesting rights percentage		50.00%
Performance Stock Units [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share based payment award award vesting rights percentage		50.00%

Balance Sheet Components - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accrued liabilities:
Clinical and preclinical costs	$ 9,163	$ 5,880
Compensation related	16,167	29,255
Other accrued expenses	14,793	7,506
Total accrued liabilities	$ 40,123	$ 42,641

Balance Sheet Components - Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 119,976	$ 113,024
Restricted cash	375	375
Total cash, cash equivalents, and restricted cash as reported within our consolidated statement of cash flows	$ 120,351	$ 113,399	$ 103,216	$ 67,182

Organization and Significant Accounting Policies

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Significant Accounting Policies

Note 1 — Organization and Significant Accounting Policies

Cytokinetics, Incorporated was incorporated under the laws of the state of Delaware on August 5, 1997. The Company is a late-stage biopharmaceutical company focused on the discovery and development of novel small molecule therapeutics that modulate muscle function for the potential treatment of serious diseases and medical conditions.

Our financial statements contemplate the conduct of our operations in the normal course of business. We have incurred an accumulated deficit of approximately $2.2 billion since inception and there can be no assurance that we will attain profitability. We had a net loss of $135.6 million and net cash used in operations of $129.5 million for the three months ended March 31, 2024. Cash, cash equivalents, and investments decreased to $634.3 million as of March 31, 2024 from $655.4 million as of December 31, 2023. We anticipate that we will have operating losses and net cash outflows in future periods.

We are subject to risks common to late-stage biopharmaceutical companies including, but not limited to, development of new drug candidates, dependence on key personnel, and the ability to obtain additional capital as needed to fund our future plans. Our liquidity will be impaired if sufficient additional capital is not available on terms acceptable to us. To date, we have funded operations primarily through sales of our common stock, contract payments under our collaboration agreements, sales of future revenues and royalties, debt financing arrangements and interest income. Until we achieve profitable operations, we intend to continue to fund operations through payments from strategic collaborations, additional sales of equity securities, grants and debt financings. We have never generated revenues from commercial sales of our drugs and may not have drugs to market for at least several years, if ever. Our success is dependent on our ability to enter into new strategic collaborations and/or raise additional capital and to successfully develop and market one or more of our drug candidates. We cannot be certain that sufficient funds will be available from such a financing or through a collaborator when required or on satisfactory terms. Additionally, there can be no assurance that our drug candidates will be accepted in the marketplace or that any future products can be developed or manufactured at an acceptable cost. These factors could have a material adverse effect on our future financial results, financial position and cash flows.

Based on the current status of our research and development activities, we believe that our existing cash, cash equivalents and investments will be sufficient to fund cash requirements for at least the next 12 months after the issuance of this Quarterly Report on Form 10-Q. If, at any time, our prospects for financing our research and development programs decline, we may decide to reduce research and development expenses by delaying, discontinuing or reducing our funding of one or more of our research or development programs. Alternatively, we might raise funds through strategic collaborations, public or private financings or other arrangements. Such funding, if needed, may not be available on favorable terms, or at all. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis of Presentation

Our condensed consolidated financial statements include the accounts of Cytokinetics and our wholly-owned subsidiaries. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The financial statements include all adjustments (consisting only of normal recurring adjustments) that management believes are necessary for the fair statement of our financial information. These interim results are not necessarily indicative of results to be expected for the full fiscal year or any future interim period. The balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by GAAP for complete financial statements. The financial statements and related disclosures have been prepared with the presumption that users of the interim financial statements have read or have access to the audited financial statements for the preceding fiscal year. Accordingly, these financial statements should be read in conjunction with the audited financial statements and notes thereto contained in the Company’s Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. We evaluate our estimates on an ongoing basis. We base our estimates on our historical experience and also on assumptions that we believe are reasonable; however, actual results could significantly differ from those estimates.

Recently Issued Accounting Pronouncements

In November 2023, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This standard requires disclosure of significant segment expenses and other segment items by reportable segment. The ASU becomes effective for annual periods beginning in 2024 and interim periods in 2025.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This standard enhances disclosures related to income taxes, including the rate reconciliation and information on income taxes paid. The ASU becomes effective January 1, 2025.

Stockholders' Equity - Summary of Warrants Outstanding to Purchase Shares of Common Stock (Details) - Oxford and Silicon Valley Bank [Member] - January 2020 [Member] - New Loan and Security Agreement [Member] - 2019 Term Loan [Member] - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Exercise Price		$ 10.42
Expiration Date		2030-01
Warrants Outstanding	0	12,957
Warrants Exercised	12,957
Common Shares Issued upon Exercise of Warrants	11,335

Net Loss Per Share

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Net Loss Per Share

Note 2 — Net Loss Per Share

The following instruments were excluded from the computation of diluted net loss per share for the periods presented because their effect would have been antidilutive (in thousands):


	March 31, 2024		March 31, 2023
Options to purchase common stock		11,095		12,362
Warrants to purchase common stock		—		13
Restricted stock and performance units		1,692		1,438
Shares issuable related to the ESPP		65		49
Shares issuable upon conversion of 2026 Notes		2,003		2,003
Shares issuable upon conversion of 2027 Notes		10,572		10,572
Total shares		25,427		26,437

Research and Development Arrangements - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			3 Months Ended		12 Months Ended
	Dec. 20, 2021	Apr. 23, 2020	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2021	Dec. 31, 2020	Jul. 14, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues			$ 835	$ 4,613
Accounts receivable			834		$ 1,283
Amount received as milestone payment			2,500
Net proceeds of issuance of common stock			93,640	0
Ji Xing Omecamtiv Mecarbil License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Nonrefundable payment obligation	$ 50,000
Ji Xing Aficamten License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts receivable			800		300
Upfront payment received								$ 25,000
Common Stock Purchase Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Shares Issued, price per share	$ 39.125
Shares, Issued	0.5
Net proceeds of issuance of common stock	$ 20,000
Common stock purchase agreement date	Dec. 31, 2021
Maximum [Member] \| Ji Xing Omecamtiv Mecarbil License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential additional payments receivable	$ 330,000
Maximum [Member] \| Ji Xing Aficamten License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential additional payments receivable								$ 200,000
2016 Astellas Amendment [Member] \| Maximum [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment of development costs for clinical trials of reldesemtiv		$ 12,000
Reimbursement of clinical development costs					12,000
Rights Granted [Member] \| Ji Xing Omecamtiv Mecarbil License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Nonrefundable payment obligation	40,000
New Drug Application [Member] \| Ji Xing Omecamtiv Mecarbil License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Nonrefundable payment obligation	$ 10,000
License Revenues [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues						$ 54,900
License Revenues [Member] \| Ji Xing Aficamten License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues							$ 36,500
Research and Development Revenues [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues			835	2,113
Research and Development Revenues [Member] \| Ji Xing Aficamten License and Collaboration Agreement [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues			800		$ 300
Astellas [Member] \| Research and Development Revenues [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenues			$ 0	$ 1,800

Agreements with Royalty Pharma

3 Months Ended

Mar. 31, 2024

Agreements with Royalty Pharma [Abstract]

Agreements with Royalty Pharma

Note 6 — Agreements with Royalty Pharma

On January 7, 2022, we announced that we had entered into the 2022 RPI Transactions with affiliates of Royalty Pharma International plc.

The RP Loan Agreement and the RP Aficamten RPA described below, are determined to be debt instruments subsequently measured at amortized cost and were entered into with parties that were at the time of our entry into the 2022 RPI Transactions affiliated and in contemplation of one another. We used the relative fair value method and made separate estimates of the fair value of each freestanding financial instrument and then allocated the proceeds in proportion to those fair value amounts. Arrangement consideration for the RP Loan Agreement and the RP Aficamten RPA totaled $150 million, consisting of the two $50 million upfront payments for the signing of the RP Loan Agreement and the RP Aficamten RPA and milestone of $50 million for initiation of the first pivotal trial in oHCM for aficamten that was deemed probable at the signing of the agreements.

The initial consideration was allocated as follows (in thousands):


	Fair Value		Proceeds		Allocation
Units of Accounting:
Revenue Participation Right Purchase Agreement	$	69,498	$	100,000	$	89,571
Development Funding Loan Agreement		46,887		50,000		60,429
Total consideration	$	116,385	$	150,000	$	150,000

2022 RP Loan Agreement

Under the RP Loan Agreement, we were initially entitled to receive up to $300.0 million in term loans, $50.0 million of which was disbursed to us on closing and the remaining $250.0 million scheduled to have been available to us upon our satisfaction of customary disbursement conditions and certain development conditions by specific deadlines, as follows:

•

$50.0 million of tranche 2 term loans during the one year period following the receipt on or prior to March 31, 2023 of marketing approval from FDA of omecamtiv mecarbil;

•

$25.0 million of tranche 3 term loans during the one year period following the commercial availability of a diagnostic test measuring levels of omecamtiv mecarbil to support the final FDA label language applicable to such drug, subject to such commercial availability and the conditions to the tranche 2 term loans having occurred on or prior to March 31, 2023;

•

$75.0 million of tranche 4 term loans during the one year period following the receipt on or prior to September 30, 2024 of positive results from SEQUOIA-HCM, the Phase 3 trial for aficamten; and

•

$100.0 million of tranche 5 term loans during the one year period following the acceptance by the FDA on or prior to March 31, 2025 of an NDA for aficamten, subject to the conditions to the tranche 4 term loans having occurred on or prior to September 30, 2024.

As a result of our receipt of a CRL on February 28, 2023, in connection to our NDA for omecamtiv mecarbil, we have not satisfied the conditions to the availability of the tranche 2 and tranche 3 loans under the RP Loan Agreement.

In December 2023, we announced positive topline results from SEQUOIA-HCM, the Phase 3 trial for aficamten. This entitled us to receive $75.0 million under tranche 4 during the one year period following the receipt of the positive results and requires us to complete a minimum mandatory draw of at least $50.0 million of the $75.0 million available.

The remaining $100.0 million under tranche 5 remains available for disbursement to us, subject to satisfaction of the conditions described above.

Each term loan under the RP Loan Agreement matures on the 10 year anniversary of the funding date for such term loan and is repayable in quarterly installments of principal, interest and fees commencing on the last business day of the seventh full calendar quarter following the calendar quarter of the applicable funding date for such term loan, with the aggregate amount payable in respect of each term loan (including interest and other applicable fees) equal to 190% of the principal amount of the term loan for the tranche 1, tranche 4 and tranche 5 term loans and 200% of the principal amount of the term loan for tranche 2 and tranche 3 term loans (such amount with respect to each term loan, “Final Payment Amount”). We accounted for amounts initially drawn under the RP Loan Agreement using the effective interest method which resulted in an effective interest rate of 7.65% over the ten-year term. As of the date of the prepayment or maturity of the term loan (or the date such prepayment or repayment is required to be paid), we will be required to pay an additional amount equal to $34.6 million accreted over the term of the loan. We have made our first payment in the fourth quarter of 2023.

We may prepay the term loans in full (but not in part) at any time at our option by paying an amount equal to the unpaid portion of Final Payment Amount for the outstanding term loans under the RP Loan Agreement; provided that if the conditions for either the tranche 4 term loans or the tranche 5 term loans have been met, we must have borrowed at least $50 million principal amount of the tranche 4 or 5 term loans. In addition, the term loans under the RP Loan Agreement are repayable in full at the option of either us or the lender in an amount equal to the unpaid portion of Final Payment Amount for the outstanding term loans upon a change of control of Cytokinetics.

Future minimum payments under the existing borrowing under RP Loan Agreement are (in thousands):


Years ending December 31:
2024 remainder	$	8,640
2025		11,520
2026		11,520
2027		11,520
2028		11,520
Thereafter		37,440
Future minimum payments		92,160
Less: Unamortized interest and loan costs		(23,818	)
Term Loan, net	$	68,342

As of March 31, 2024, the estimated fair value of our RP Loan Agreement was $51.9 million. The fair value was estimated based on Level 3 inputs.

2022 RP Aficamten Royalty Purchase Agreement

In addition, on January 7, 2022, we entered into the RP Aficamten RPA with RPI ICAV, pursuant to which RPI ICAV purchased rights to certain revenue streams from net sales of pharmaceutical products containing aficamten by us, our affiliates and our licensees in exchange for up to $150.0 million in consideration, $50.0 million of which was paid on the closing date, $50.0 million of which was paid to us in March 2022 following the initiation of the first pivotal trial in oHCM for aficamten, and $50.0 million of which was paid to us in September 2023 following the initiation of the first pivotal clinical trial in nHCM for aficamten. The RP Aficamten RPA also provides that the parties will negotiate terms for additional funding if we achieve proof of concept results in certain other indications for aficamten, with a reduction in the applicable royalty if we and RPI ICAV fail to agree on such terms in certain circumstances.

Pursuant to the RP Aficamten RPA, RPI ICAV purchased the right to receive a percentage of net sales equal to 4.5% for annual worldwide net sales of pharmaceutical products containing aficamten up to $1 billion and 3.5% for annual worldwide net sales of pharmaceutical products containing aficamten in excess of $1 billion, subject to reduction in certain circumstances. Our liability to RPI ICAV is referred to as the “RP Aficamten Liability”.

We account for the RP Aficamten Liability as a liability primarily because we have significant continuing involvement in generating the related revenue stream from which the liability will be repaid. If and when aficamten is commercialized and royalties become due, we will recognize the portion of royalties paid to RPI ICAV as a decrease to the RP Aficamten Liability and a corresponding reduction in cash.

The carrying amount of the RP Aficamten Liability is based on our estimate of the future royalties to be paid to RPI ICAV over the life of the arrangement as discounted using an imputed rate of interest. The imputed rate of interest on the carrying value of the RP Aficamten Liability was approximately 24.8% and 22.4% as of March 31, 2024 and 2023, respectively.

2017 RP Omecamtiv Mecarbil Royalty Purchase Agreement

In February 2017, we entered into the RP OM RPA pursuant to which we sold a portion of our right to receive royalties from Amgen on future net sales of omecamtiv mecarbil to RPFT for a one-time payment of $90 million, which is non-refundable even if omecamtiv mecarbil is never commercialized. Concurrently, we entered into a common stock purchase agreement with RPFT through which RPFT purchased 875,656 shares of the Company’s common stock for $10.0 million. We allocated the consideration and issuance costs on a relative fair value basis to our liability to RPFT related to sale of future royalties under the RP OM RPA (the “RP OM Liability”) and the common stock sold to RPFT, which resulted in the RP OM Liability being initially recognized at $92.3 million. The RP OM RPA provides for the sale of a royalty to RPFT of 4.5% on worldwide net sales of omecamtiv mecarbil, subject to a potential increase of up to an additional 1% under certain circumstances. As a result of our receipt of a CRL on February 28, 2023 in connection to our NDA for omecamtiv mecarbil, pursuant to the terms of the RP OM RPA, the applicable royalty rate will increase to a maximum of 5.5% if omecamtiv approval obtains FDA approval at any time after June 30, 2023.

As a result of the termination of the Amgen Agreement and pursuant to our obligations under the RP OM RPA, we and RPFT amended the RP OM RPA on January 7, 2022 to preserve RPFT’s rights under the RP OM RPA by providing for direct payments by us to RPFT of up to 5.5% of our and our affiliates and licensees worldwide net sales of omecamtiv mecarbil. The RP OM RPA, as amended, had no impact on the original accounting for the $92.3 million associated with the RP OM Liability established in February 2017.

We account for the RP OM Liability as a liability primarily because we have significant continuing involvement in generating the related revenue stream from which the liability will be repaid. If and when omecamtiv mecarbil is commercialized and royalties become due, we will recognize the portion of royalties paid to RPFT as a decrease to the RP OM Liability and a corresponding reduction in cash.

The carrying amount of the RP OM Liability is based on our estimate of the future royalties to be paid to RPFT over the life of the arrangement as discounted using an imputed rate of interest. The excess of future estimated royalty payments over the $92.3 million of allocated proceeds, less issuance costs, is recognized as non-cash interest expense using the effective interest method. The imputed rate of interest on the carrying value of the RP OM Liability was approximately 0.1% and 1.9% as of March 31, 2024 and 2023, respectively.

Accounting for the Royalty Pharma Royalty Purchase Agreements

We periodically assess the amount and timing of expected royalty payments using a combination of internal projections and forecasts from external sources. To the extent such payments are greater or less than our initial estimates or the timing of such payments is materially different than its original estimates, we will prospectively adjust the amortization of the RP OM Liability and the RP Aficamten Liability and the effective interest rate.

There are a number of factors that could materially affect the amount and timing of royalty payments, a number of which are not within our control. The RP OM Liability and the RP Aficamten Liability are recognized using significant unobservable inputs. The estimates of future royalties requires the use of several assumptions such as: the probability of clinical success, the probability of regulatory approval, the estimated date of a product launch, estimates of eligible patient populations, estimates of prescribing behavior and patient compliance behavior, estimates of pricing, payor reimbursement and coverage, and sales ramp. A significant change in unobservable inputs could result in a material increase or decrease to the effective interest rate of the RP OM Liability and the RP Aficamten Liability.

We recorded $50.0 million of additional consideration associated with the 2022 RP Aficamten Royalty Purchase Agreement upon receipt of the cash in the third quarter of 2023.

We review our assumptions on a regular basis and our estimates may change in the future as we refine and reassess our assumptions.

Changes to the RP Aficamten Liability and the RP OM Liability are as follows (in thousands):


	RP Aficamten Liability				RP OM Liability
	2024		2023		2024			2023
Beginning balance, January 1	$	180,591	$	105,117	$	199,384		$	195,384
Initial carrying value		—		—		—			—
Interest accretion		10,239		5,363		(21	)		917
Amortization of issuance costs		—		—		26			33
Ending balance, March 31	$	190,830	$	110,480	$	199,389		$	196,334

Agreements with Royalty Pharma - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 07, 2022	Mar. 31, 2022	Feb. 28, 2017	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Jul. 01, 2023	Mar. 31, 2023	Dec. 31, 2022
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Long term debt				$ 629,818
Debt Instrument, Face Amount				561,132
Arrangement consideration of debt transaction	$ 150,000
Liabilities				1,204,242			$ 1,210,639
RP Loan Agreement [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Long term debt				$ 68,342
2022 Royalty Pharma Transactions [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Milestone payment	50,000
2022 Royalty Pharma Transactions [Member] \| RP Aficamten RPA, RPI ICAV [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Upfront payment	50,000
Purchased rights to certain revenue streams from net sales in consideration payment	$ 50,000
Percentage of net sales payable	4.50%
4.5% of net revenue to be receivable from annual worldwide net sales	$ 1,000,000
Percentage of net sales payable for excess of annual worldwide net sales	3.50%
3.5% of net sales payable for excess of annual worldwide net sales	$ 1,000,000
Imputed rate of interest on unamortized portion of liability				24.80%					22.40%
2022 Royalty Pharma Transactions [Member] \| RP Aficamten RPA, RPI ICAV [Member] \| oHCM [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Additional consideration amount paid of first pivotal clinical trail		$ 50,000
2022 Royalty Pharma Transactions [Member] \| RP Aficamten RPA, RPI ICAV [Member] \| nHCM [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Additional consideration amount paid of first pivotal clinical trail						$ 50,000
2022 Royalty Pharma Transactions [Member] \| RP Aficamten RPA, RPI ICAV [Member] \| Maximum [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Purchased rights to certain revenue streams from net sales in consideration payment	$ 150,000
2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Estimated fair value of long term debt				$ 51,900
Term loan, maturity year	10 years
Debt instrument effective interest rate	7.65%
Applicable prepayment charges on term loan	$ 34,600
Debt Instrument, Face Amount	$ 50,000
2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 1 Tranche 4 and Tranche 5 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Repayable loan percentage to principal amount Including interest and other fees	190.00%
2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 2 and Tranche 3 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Repayable loan percentage to principal amount Including interest and other fees	200.00%
2022 Royalty Pharma Transactions [Member] \| RP Aficamten RPA [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Additional consideration amount paid					$ 50,000
Royalty Purchase Finance Trust Agreement [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Liabilities related to revenue participation right purchase agreements, net				$ 199,389			$ 199,384		$ 196,334	$ 195,384
Royalty Purchase Finance Trust Agreement [Member] \| RP OM RPA [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Imputed rate of interest on unamortized liability				0.10%					1.90%
Non-cash interest expense recognized				$ 92,300
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Term loan, maximum borrowing capacity	$ 300,000
Term loan, current borrowing capacity	50,000
Term loan, remaining borrowing capacity	250,000
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 2 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Long term debt	50,000
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 3 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Long term debt	25,000
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 4 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Term loan, maximum borrowing capacity				75,000
Long term debt	75,000
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 4 [Member] \| Minimum [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Term loan, current borrowing capacity				50,000
CRL Option [Member] \| 2022 Royalty Pharma Transactions [Member] \| RP Loan Agreement [Member] \| Term Loan Tranche 5 [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Term loan, remaining borrowing capacity				$ 100,000
Long term debt	$ 100,000
CRL Option [Member] \| Royalty Purchase Finance Trust Agreement [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Cash payment under royalty agreement			$ 90,000
Purchase of common stock shares			875,656
Stock issued during period, value, issued for services			$ 10,000
Liabilities			$ 92,300
Additional percent of royalty on net sale			1.00%
CRL Option [Member] \| Royalty Purchase Finance Trust Agreement [Member] \| Maximum [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Percent of royalty on net sale	5.50%
Increase in royalty rate								5.50%
CRL Option [Member] \| Royalty Purchase Finance Trust Agreement [Member] \| Minimum [Member]
Liabilities Related to Revenue Participation Right Purchase Agreements [Line Items]
Percent of royalty on net sale			4.50%

Debt

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Debt

Note 7 — Debt

Convertible Notes

On November 13, 2019, we issued $138.0 million aggregate principal amount of 2026 Notes. On July 6, 2022, we issued $540.0 million aggregate principal amount of 2027 Notes and used approximately $140.3 million of the net proceeds from the offering of 2027 Notes and issued 8,071,343 shares of common stock to repurchase approximately $116.9 million aggregate principal amount of the 2026 Notes pursuant to privately negotiated exchange agreements entered into with certain holders of the 2026 Notes concurrently with the pricing of the offering of the 2027 Notes. As of March 31, 2024, there remains $21.1 million aggregate principal amount of 2026 Notes outstanding and $540.0 million of aggregate principal amount of 2027 Notes outstanding.

The 2026 Notes are unsecured obligations and bear interest at an annual rate of 4.0% per year, payable semi-annually on May 15 and December 15 of each year, beginning May 15, 2020. The 2026 Notes will mature on November 15, 2026, unless earlier repurchased or redeemed by us or converted at the option of the holders. We may redeem the 2026 Notes prior to the maturity date but we are not required to and no sinking fund is provided for the 2026 Notes. The 2026 Notes may be converted, under certain circumstances, based on an initial conversion rate of 94.7811 shares of common stock per $1,000 principal amount (which represents an initial conversion price of $10.55 per share).

The 2027 Notes are our senior unsecured obligations and shares equal in right of payment with our other indebtedness, including the 2026 Notes. The 2027 Notes bear interest at a rate of 3.5% per year, payable semiannually in arrears on January 1 and July 1 of each year, beginning on January 1, 2023. The 2027 Notes will mature on July 1, 2027, unless earlier converted, redeemed or repurchased. The 2027 Notes are convertible into cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s). The initial conversion rate for the 2027 Notes is 19.5783 shares of our common stock per $1,000 principal amount of such Notes, which is equivalent to an initial conversion price of approximately $51.08 per share.

The conversion rate for the 2026 Notes and 2027 Notes will be subject to adjustment upon the occurrence of certain specified events as described above. In addition, upon the occurrence of a make-whole fundamental change (as defined in the indenture), we will, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its notes in connection with such make-whole fundamental change.

The 2026 Notes are redeemable, in whole or in part, at our option at any time, and from time to time, and, in the case of any partial redemption, on or before the 60th scheduled trading day before the maturity date, at a cash redemption price equal to the principal amount of the 2026 Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we may send the related redemption notice; and (ii) the trading day immediately before the date we may send such notice.

Holders of the 2027 Notes have the option to convert their convertible notes only in the following circumstances: (i) if the last reported sale price per share of our common stock exceeds 130% of the conversion price for at least 20 trading days within a 30-day period starting from the last trading day of the preceding quarter after September 30, 2022; (ii) within 5 consecutive business days following any 10 consecutive trading day period if the trading price per $1,000 principal amount of 2027 Notes during such period falls below 98% of the product of the last reported sale price per share of our common stock and the conversion rate; (iii) upon certain corporate events or distributions on our common stock outlined in the 2027 Indenture; (iv) upon our call for redemption of the 2027 Notes; and (v) from March 1, 2027, until the scheduled trading day immediately preceding the maturity date. Circumstance (i) defined above was triggered upon the calculation completed for April 1, 2024. Consequently the 2027 Notes are redeemable at the option of the holders for the second quarter of 2024. This calculation will continue to be re-evaluated on a quarterly basis.

We may not redeem the 2027 Notes at our option at any time before July 7, 2025. The 2027 Notes will be redeemable, in whole or in part (subject to the “Partial Redemption Limitation” (as defined in the 2027 Indenture)), at our option at any time, and from time to time, on or after July 7, 2025

The following table presents the total amount of interest cost recognized relating to the 2026 Notes (in thousands):


	Three Months Ended
	March 31, 2024		March 31, 2023
Contractual interest expense	$	212	$	211
Amortization of debt issuance costs		28		23
Total interest expense recognized	$	240	$	234

The effective interest rate of the 2026 Notes was 4.6% for the three months ended March 31, 2024 and 2023. As of March 31, 2024, the unamortized debt issuance cost for the 2026 Notes was $0.3 million and will be amortized over approximately 2.7 years. The 2026 Notes are convertible at March 31, 2024 at the option of the holder.

The following table presents the total amount of interest cost recognized relating to the 2027 Notes (in thousands):


	Three Months Ended
	March 31, 2024		March 31, 2023
Contractual interest expense	$	4,725	$	4,724
Amortization of debt issuance costs		773		682
Total interest expense recognized	$	5,498	$	5,406

The effective interest rate of the 2027 Notes was 4.2% as of March 31, 2024 and 2023. As of March 31, 2024, the unamortized debt issuance cost for the 2027 Notes was $11.0 million and will be amortized over approximately 3.3 years. During the three months ended March 31, 2024, the conditions allowing holders of the 2027 Notes to convert were not met. As a result, the 2027 Notes are not convertible during the three months ended March 31, 2024.

Future minimum payments under the 2027 Notes and 2026 Notes are (in thousands):


Years ending December 31:	2027 Notes			2026 Notes			Total
2024 remainder	$	9,450		$	845		$	10,295
2025		18,900			845			19,745
2026		18,900			21,978			40,878
2027		558,900			—			558,900
Future minimum payments		606,150			23,668			629,818
Less: Interest		(66,150	)		(2,536	)		(68,686	)
Convertible notes, principal amount		540,000			21,132			561,132
Less: Debt issuance costs on the convertible notes		(11,025	)		(317	)		(11,342	)
Net carrying amount of the convertible notes	$	528,975		$	20,815		$	549,790

As of March 31, 2024, the estimated fair value of the 2027 Notes and 2026 Notes was $866.6 million and $141.7 million, respectively, and was based upon observable, Level 2 inputs, including pricing information from recent trades of the convertible notes.

- 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.

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+ Details

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (135,643)	$ (131,289)

- 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

Stockholders' Equity

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Stockholders' Equity

Note 8 — Stockholders’ Equity

Equity Incentive Plan

Our 2004 Plan provides for us to grant incentive stock options, non-statutory stock options, restricted stock, stock appreciation rights, restricted stock units, performance shares and performance units to employees, directors, and consultants. We may grant options for terms of up to ten years at prices not lower than 100% of the fair market value of our common stock on the date of grant. Options granted to new employees generally vest 25% after one year and monthly thereafter over a period of four years. Options granted to existing employees generally vest monthly over a period of four years.

Our annual grant of stock-based compensation takes place during the first quarter of each year. Our stock options and restricted stock units granted for the first quarter of 2024 was as follows:


	Grants		Weighted Average Grant Date Fair Value per Share
Stock options		932,778	$	64.54
Restricted stock units		1,037,398	$	63.77

As of March 31, 2024, the total authorized shares under the 2004 Plan available for grant was 5.6 million.

Stock-based compensation expense was $21.6 million and $15.2 million for the three months ended March 31, 2024 and 2023, respectively.

Warrants

As of December 31, 2023, we had the following warrants outstanding to purchase shares of our common stock which were exercised in January 2024:


Issuance Date	Expiration Date	Exercise Price		Warrants Outstanding at December 31, 2023		Warrants Outstanding at March 31, 2024		Warrants Exercised during the Three Months Ended March 31, 2024		Common Shares Issued upon Exercise of Warrants
January 2020	January 2030	$	10.42		12,957		—		12,957		11,335

Controlled Equity Offering Sales Agreement with Cantor Fitzgerald & Co.

On March 1, 2023, we entered into the Amended ATM Facility, with Cantor, under which we may offer and sell, from time to time at our sole discretion, shares of the Common Stock having an aggregate offering price of up to $300.0 million through Cantor, as sales agent. The Amended ATM Facility amends, restates and supersedes the Controlled Equity Offering Sales Agreement dated as of March 6, 2019 between the Company and Cantor.

Cantor may sell the Common Stock by any method that is deemed to be an “at the market offering” as defined in Rule 415 of the Securities Act of 1933, as amended, including sales made directly on the Nasdaq Global Select Market or any other trading market for our common stock. Cantor will use commercially reasonable efforts to sell the Common Stock from time to time, based upon instructions from us (including any price, time or size limits or other customary parameters or conditions we may impose). We will pay Cantor a commission of up to 3.0% of the aggregate gross sales proceeds of any common stock sold through Cantor under the Amended ATM Facility, and also have provided Cantor with customary indemnification rights.

In 2023, we issued 5,016,170 shares of our common stock for net proceeds of $164.2 million under the Amended ATM Facility. During the three months ended March 31, 2024, we issued 1,237,460 shares of our common stock for net proceeds of $93.6 million under the Amended ATM Facility.

Performance Stock Units

In March 2024, the Compensation Committee granted a total of 359,992 performance stock units ("PSUs") to certain employees with a grant date fair value of $63.75 per unit. The fair value of the PSUs was determined on the grant date based on the fair value of the Company’s common stock at such time. The PSU awards are subject to two performance goals and will be earned as to up to 50% of the number of shares subject to the PSU award upon the certification by the Compensation and Talent Committee of the Company’s Board of Directors (the “Compensation Committee”) that the Company has achieved the first performance goal and as to up to 50% of the number of shares subject to the PSU award upon the certification by the Compensation Committee that the Company has achieved the second performance goal, in each case vesting as to 50% of the earned shares on applicable Compensation Committee certification date and as to 50% of the earned shares following the one-year anniversary of the applicable Compensation Committee certification date.

During the three months ended March 31, 2024, the Company recognized expense of $0.4 million for the PSUs. As of March 31, 2024, there was $11.1 million of unamortized stock-based compensation related to the PSUs. The Company will assess the probability of achieving the performance conditions quarterly and the expense recognized will be adjusted accordingly.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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-Subparagraph (a)
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481004/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
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-URI https://asc.fasb.org//1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//505/tableOfContent

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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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 13
-Subparagraph (i)
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Agreements with Royalty Pharma - Schedule Represents Allocation of Transaction Consideration on a Relative Fair Value Basis to the Liability and the Common Stock (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
RP Aficamten Liability [Member]
Royalty Liability [Line Items]
Liabilities related to revenue participation right purchase agreements, net beginning balance	$ 180,591	$ 105,117
Initial carrying value	0	0
Interest accretion	10,239	5,363
Amortization of issuance costs	0	0
Liabilities related to revenue participation right purchase agreements, net ending balance	190,830	110,480
RPOM Liability [Member]
Royalty Liability [Line Items]
Liabilities related to revenue participation right purchase agreements, net beginning balance	199,384	195,384
Initial carrying value	0	0
Interest accretion	(21)	917
Amortization of issuance costs	26	33
Liabilities related to revenue participation right purchase agreements, net ending balance	$ 199,389	$ 196,334

Research and Development Arrangements

3 Months Ended

Mar. 31, 2024

Research and Development [Abstract]

Research and Development Arrangements

Note 3 — Research and Development Arrangements

Ji Xing Omecamtiv Mecarbil License and Collaboration Agreement

On December 20, 2021, we entered into the Ji Xing OM License Agreement, pursuant to which we granted to Ji Xing an exclusive license to develop and commercialize omecamtiv mecarbil in China and Taiwan. Under the terms of the Ji Xing OM License Agreement, we received a $50.0 million nonrefundable payment from Ji Xing comprised of a $40.0 million payment as consideration for the rights granted by us to Ji Xing and $10.0 million attributable to our having submitted to FDA an NDA for omecamtiv mecarbil. We may be eligible to receive from Ji Xing additional payments totaling up to $330.0 million for the achievement of certain commercial milestone events in China and Taiwan in connection to omecamtiv mecarbil. In addition, Ji Xing will pay us tiered royalties in the mid-teens to the low twenties range on the net sales of pharmaceutical products containing omecamtiv mecarbil in China and Taiwan, subject to certain reductions for generic competition, patent expiration and payments for licenses to third party patents. The Ji Xing OM License Agreement, unless terminated earlier, will continue on a market-by-market basis until expiration of the relevant royalty term.

In addition to the Ji Xing OM License Agreement, we entered into common stock purchase agreements with each of the RTW Investors, pursuant to which we sold and issued an aggregate of 0.5 million shares of our common stock at a price per share of $39.125 and an aggregate purchase price of $20.0 million. The closing of the transaction occurred on December 31, 2021.

Ji Xing Aficamten License and Collaboration Agreement

On July 14, 2020, we entered into the Ji Xing Aficamten License Agreement, pursuant to which we granted to Ji Xing an exclusive license to develop and commercialize aficamten in China and Taiwan. Under the terms of the Ji Xing Aficamten License Agreement, we received from Ji Xing a nonrefundable upfront payment of $25.0 million. Under the terms of the Ji Xing Aficamten License Agreement, we may be eligible to receive from Ji Xing milestone payments totaling up to $200.0 million for the achievement of certain development and commercial milestone events in connection to aficamten in the field of oHCM, and/or nHCM and other indications. In addition, Ji Xing will pay us tiered royalties in the low-to-high teens range on the net sales of pharmaceutical products containing aficamten in China and Taiwan, subject to certain reductions for generic competition, patent expiration and payments for licenses to third party patents. The Ji Xing Aficamten License Agreement, unless terminated earlier, will continue on a market-by-market basis until expiration of the relevant royalty term.

Accounting for the Ji Xing License and Collaboration Agreements

We assessed the arrangements of the Ji Xing OM License Agreement and the Ji Xing Aficamten License Agreement in accordance with ASC 606 and concluded that there is one performance obligation relating to the license of functional intellectual property for each agreement. The performance obligation was satisfied, and we recognized the residual allocation of arrangement consideration as revenue of $54.9 million in 2021 for the Ji Xing OM License Agreement and $36.5 million in 2020 for the Ji Xing Aficamten License Agreement. Due to the nature of development, including the inherent risk of development and approval by regulatory authorities, we are unable to estimate if and when the development milestone payments could be achieved or become due and, accordingly, we consider the milestone payments to be fully constrained and exclude the milestone payments from the initial transaction price.

The consideration related to sales-based milestone payments, including royalties, will be recognized when the related sales occur under the sales and usage-based royalty exception of ASC 606 as these amounts have been determined to relate predominantly to the license.

We re-evaluate the probability of achievement of development milestones and any related constraints each reporting period. We will include consideration, without constraint, in the transaction price to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur.

We recognized a $2.5 million milestone from Ji Xing in 2023 for the initiation of a phase 3 clinical trial for aficamten in nHCM which was collected in the fourth quarter of 2023.

Research and development revenue from Ji Xing for the three months ended March 31, 2024 and 2023 was $0.8 million and $0.3 million, respectively, related to certain development cost reimbursements.

We had accounts receivable from Ji Xing of $0.8 million as of March 31, 2024 and $0.3 million as of December 31, 2023.

Astellas

The Company and Astellas entered into the Astellas FSRA Agreement on April 23, 2020. As a result of the Astellas FSRA Agreement, the Company will now have exclusive control and responsibility for the Company's future development and commercialization of reldesemtiv, CK-601 and other FSRA compounds and products, and accordingly, Astellas has agreed to terminate its license to all FSRA compounds and related products.

Under the Astellas FSRA Agreement, Astellas agreed to pay one-third of the out-of-pocket clinical development costs which may be incurred in connection with the Company’s Phase 3 clinical trial of reldesemtiv in ALS, up to a maximum contribution by Astellas of $12 million. Astellas also agreed to non-cash contributions to the Company, which included the transfer of its existing inventories of active pharmaceutical ingredient of reldesemtiv and CK-601. As of December 31, 2023, we have billed and collected from Astellas up to the maximum contribution of $12.0 million. On March 31, 2023, we announced that we will discontinue COURAGE-ALS, our Phase 3 clinical trial of reldesemtiv in patients with ALS, and COURAGE-ALS OLE.

We had no research and development revenue from Astellas for the three months ended March 31, 2024. Research and development revenue from Astellas was $1.8 million for the three months ended March 31, 2023.

Stockholders' Equity - Summary of Stock Options and Restricted Stock Units Granted (Details)	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Employee Stock Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock options, Grants \| shares	932,778
Stock options, Weighted average date fair value per share \| $ / shares	$ 64.54
Restricted Stock Units [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock units, Grants \| shares	1,037,398
Restricted stock units, Weighted average date fair value per share \| $ / shares	$ 63.77

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 35
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+ Details

Net Loss Per Share - Instruments Excluded from the Computation of Diluted Net Loss Per Share (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	25,427	26,437
Options to purchase common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	11,095	12,362
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	0	13
Restricted Stock and Performance Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	1,692	1,438
Shares Issuable Related to the ESSP [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	65	49
2026 Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	2,003	2,003
2027 Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares	10,572	10,572

Debt (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of Interest Cost Relating to Notes

The following table presents the total amount of interest cost recognized relating to the 2026 Notes (in thousands):


	Three Months Ended
	March 31, 2024		March 31, 2023
Contractual interest expense	$	212	$	211
Amortization of debt issuance costs		28		23
Total interest expense recognized	$	240	$	234

The following table presents the total amount of interest cost recognized relating to the 2027 Notes (in thousands):


	Three Months Ended
	March 31, 2024		March 31, 2023
Contractual interest expense	$	4,725	$	4,724
Amortization of debt issuance costs		773		682
Total interest expense recognized	$	5,498	$	5,406

Schedule of Maturities of Notes

Future minimum payments under the 2027 Notes and 2026 Notes are (in thousands):


Years ending December 31:	2027 Notes			2026 Notes			Total
2024 remainder	$	9,450		$	845		$	10,295
2025		18,900			845			19,745
2026		18,900			21,978			40,878
2027		558,900			—			558,900
Future minimum payments		606,150			23,668			629,818
Less: Interest		(66,150	)		(2,536	)		(68,686	)
Convertible notes, principal amount		540,000			21,132			561,132
Less: Debt issuance costs on the convertible notes		(11,025	)		(317	)		(11,342	)
Net carrying amount of the convertible notes	$	528,975		$	20,815		$	549,790

Agreements with Royalty Pharma - Schedule of Future Minimum Payments under Term Loan Agreement (Detail) $ in Thousands	Mar. 31, 2024 USD ($)
Debt Instrument [Line Items]
2024 remainder	$ 10,295
2025	19,745
2026	40,878
2027	558,900
Less: Unamortized interest and loan costs	(11,342)
Term Loan, net	629,818
RP Loan Agreement [Member]
Debt Instrument [Line Items]
2024 remainder	8,640
2025	11,520
2026	11,520
2027	11,520
2028	11,520
Thereafter	37,440
Future minimum payments	92,160
Less: Unamortized interest and loan costs	(23,818)
Term Loan, net	$ 68,342

Balance Sheet Components

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

Note 5 — Balance Sheet Components

A reconciliation of cash, cash equivalents, and restricted cash reported in the accompanying condensed consolidated balance sheets to the amount reported within the accompanying condensed consolidated statements of cash flows was as follows (in thousands):


	March 31, 2024		December 31, 2023
Cash and cash equivalents	$	119,976	$	113,024
Restricted cash		375		375
Total cash, cash equivalents, and restricted cash as reported within our consolidated statement of cash flows	$	120,351	$	113,399

As of March 31, 2024, our restricted cash balance of $0.4 million is used to collateralize letters of credit.

Accrued liabilities were as follows (in thousands):


	March 31, 2024		December 31, 2023
Accrued liabilities:
Clinical and preclinical costs	$	9,163	$	5,880
Compensation related		16,167		29,255
Other accrued expenses		14,793		7,506
Total accrued liabilities	$	40,123	$	42,641

Condensed Consolidated Statements of Stockholders' Deficit (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2022	$ (107,900)	$ 94	$ 1,481,590	$ (3,590)	$ (1,585,994)
Beginning Balance, shares at Dec. 31, 2022		94,833,975
Exercise of stock options, value	3,547	$ 0	3,547	0	0
Exercise of stock options, shares		369,298
Vesting of restricted stock units, value	0	$ 0	0	0	0
Vesting of restricted stock units, shares		668,835
Shares withheld related to net share settlement of equity awards, value	(10,517)	$ 0	(10,517)	0	0
Shares withheld related to net share settlement of equity awards, shares		(262,829)
Stock-based compensation	15,194	$ 0	15,194	0	0
Other comprehensive income (loss)	1,945	0	0	1,945	0
Net Income (Loss)	(131,289)	0	0	0	(131,289)
Ending Balance at Mar. 31, 2023	(229,020)	$ 94	1,489,814	(1,645)	(1,717,283)
Ending Balance, shares at Mar. 31, 2023		95,609,279
Beginning Balance at Dec. 31, 2023	(386,323)	$ 102	1,725,823	(10)	(2,112,238)
Beginning Balance, shares at Dec. 31, 2023		101,637,922
Exercise of stock options, value	29,532	$ 2	29,530	0	0
Exercise of stock options, shares		1,466,359
Vesting of restricted stock units, value	0	$ 0	0	0	0
Vesting of restricted stock units, shares		695,140
Shares withheld related to net share settlement of equity awards, value	(18,449)	$ 0	(18,449)	0	0
Shares withheld related to net share settlement of equity awards, shares		(274,256)
Issuance of common stock under at-the-market offering, net of issuance costs, value	93,640	$ 1	93,639	0	0
Issuance of common stock under at-the-market offering, net of issuance costs, shares		1,237,460
Exercise of warrants, net, value	0	$ 0	0	0	0
Exercise of warrants, net, share		11,335
Stock-based compensation	21,612	$ 0	21,612	0	0
Other comprehensive income (loss)	(529)	0	0	(529)	0
Net Income (Loss)	(135,643)	0	0	0	(135,643)
Ending Balance at Mar. 31, 2024	$ (396,160)	$ 105	$ 1,852,155	$ (539)	$ (2,247,881)
Ending Balance, shares at Mar. 31, 2024		104,773,960

Organization and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit incurred	$ (2,247,881)		$ (2,112,238)
Cash requirements term	12 months
Net Income (Loss)	$ (135,643)	$ (131,289)
Cash, cash equivalents and investments	634,300		$ 655,400
Net cash provided by (used in) operating activities	$ 129,507	$ 122,286

- Definition

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

+ References

+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Agreements with Royalty Pharma (Tables)

3 Months Ended

Mar. 31, 2024

Agreements with Royalty Pharma [Abstract]

Schedule of Initial Consideration

The initial consideration was allocated as follows (in thousands):


	Fair Value		Proceeds		Allocation
Units of Accounting:
Revenue Participation Right Purchase Agreement	$	69,498	$	100,000	$	89,571
Development Funding Loan Agreement		46,887		50,000		60,429
Total consideration	$	116,385	$	150,000	$	150,000

Schedule of Future Minimum Payments under Term Loan Agreement

Future minimum payments under the existing borrowing under RP Loan Agreement are (in thousands):


Years ending December 31:
2024 remainder	$	8,640
2025		11,520
2026		11,520
2027		11,520
2028		11,520
Thereafter		37,440
Future minimum payments		92,160
Less: Unamortized interest and loan costs		(23,818	)
Term Loan, net	$	68,342

Schedule of Activity within Liabilities Related to Sale of Future Royalties

Changes to the RP Aficamten Liability and the RP OM Liability are as follows (in thousands):


	RP Aficamten Liability				RP OM Liability
	2024		2023		2024			2023
Beginning balance, January 1	$	180,591	$	105,117	$	199,384		$	195,384
Initial carrying value		—		—		—			—
Interest accretion		10,239		5,363		(21	)		917
Amortization of issuance costs		—		—		26			33
Ending balance, March 31	$	190,830	$	110,480	$	199,389		$	196,334

Commitments and Contingencies - Additional Information (Detail) - Oyster Point Lease [Member] - California [Member]		3 Months Ended
	Mar. 31, 2021	Mar. 31, 2024
Lessee Lease Description [Line Items]
Operating lease, lease expiration date		Oct. 31, 2033
Operating lease, commencement date	Mar. 31, 2021

Debt - Schedule of Interest Cost Relating to 2026 and 2027 Notes (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
2026 Notes [Member]
Debt Instrument [Line Items]
Contractual interest expense	$ 212	$ 211
Amortization of debt issuance costs	28	23
Total interest expense recognized	240	234
2027 Notes [Member]
Debt Instrument [Line Items]
Contractual interest expense	4,725	4,724
Amortization of debt issuance costs	773	682
Total interest expense recognized	$ 5,498	$ 5,406

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Fair Value Measurements

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 4 — Fair Value Measurements

We value our financial assets and liabilities at fair value, defined as the price that would be received for assets when sold or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We utilize market data or assumptions that we believe market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable.

We primarily apply the market approach for recurring fair value measurements and endeavor to utilize the best information reasonably available. Accordingly, we use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible and consider the security issuers’ and the third-party issuers’ credit risk in our assessment of fair value.

We classify fair value based on the observability of those inputs using a hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement):

Level 1 — Observable inputs, such as quoted prices in active markets for identical assets or liabilities;

Level 2 — Inputs, other than the quoted prices in active markets, that are observable either directly or through corroboration with observable market data; and

Level 3 — Unobservable inputs, for which there is little or no market data for the assets or liabilities, such as internally-developed valuation models.

Fair Value of Financial Assets:

The follow tables set forth the fair value of our financial assets, which consists of cash equivalents and investments classified as available-for-sale securities, that were measured on a recurring basis (in thousands):


		March 31, 2024
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	Level 1	$	108,635	$	—	$	—		$	108,635
U.S. Treasury securities	Level 1		60,920		—		(46	)		60,874
U.S. Government agency securities	Level 2		104,159		11		(149	)		104,021
Commercial paper	Level 2		239,642		18		(229	)		239,431
Corporate obligations	Level 2		114,179		14		(164	)		114,029
		$	627,535	$	43	$	(588	)	$	626,990


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	Level 1	$	77,429	$	—	$	—		$	77,429
U.S. Treasury securities	Level 1		34,625		13		(15	)		34,623
U.S. Government agency securities	Level 2		175,301		87		(133	)		175,255
Commercial paper	Level 2		252,956		156		(59	)		253,053
Corporate obligations	Level 2		92,384		103		(142	)		92,345
		$	632,695	$	359	$	(349	)	$	632,705

No credit losses on debt securities were recognized during the three months ended March 31, 2024 or 2023. In its evaluation to determine expected credit losses, management considered all available historical and current information, expectations of future economic conditions, the type of security, the credit rating of the security, and the size of the loss position, as well as other relevant information. The Company does not intend to sell, and is unlikely to be required to sell, any of these available-for-sale investments before their effective maturity or market price recovery.

- 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

Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]
Restricted cash	$ 375	$ 375

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Summary of Fair Value of Financial Assets Consists of Cash Equivalents and Investments Classified as Available-for-sale Securities Measured on Recurring Basis


		March 31, 2024
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	Level 1	$	108,635	$	—	$	—		$	108,635
U.S. Treasury securities	Level 1		60,920		—		(46	)		60,874
U.S. Government agency securities	Level 2		104,159		11		(149	)		104,021
Commercial paper	Level 2		239,642		18		(229	)		239,431
Corporate obligations	Level 2		114,179		14		(164	)		114,029
		$	627,535	$	43	$	(588	)	$	626,990


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	Level 1	$	77,429	$	—	$	—		$	77,429
U.S. Treasury securities	Level 1		34,625		13		(15	)		34,623
U.S. Government agency securities	Level 2		175,301		87		(133	)		175,255
Commercial paper	Level 2		252,956		156		(59	)		253,053
Corporate obligations	Level 2		92,384		103		(142	)		92,345
		$	632,695	$	359	$	(349	)	$	632,705

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 119,976	$ 113,024
Short-term investments	498,985	501,800
Accounts receivable	834	1,283
Prepaid expenses and other current assets	18,909	11,944
Total current assets	638,704	628,051
Long-term investments	15,376	40,534
Property and equipment, net	68,018	68,748
Operating lease right-of-use assets	78,170	78,987
Other assets	7,814	7,996
Total assets	808,082	824,316
Current liabilities:
Accounts payable	12,967	21,507
Accrued liabilities	40,123	42,641
Short-term operating lease liabilities	18,230	17,891
Current portion of long-term debt	11,520	10,080
Other current liabilities	6,015	10,559
Total current liabilities	88,855	102,678
Term loan, net	56,822	58,384
Convertible notes, net	549,790	548,989
Liabilities related to revenue participation right purchase agreements, net	390,219	379,975
Long-term operating lease liabilities	118,554	120,427
Other non-current liabilities	2	186
Total liabilities	1,204,242	1,210,639
Commitments and contingencies
Stockholders' deficit:
Preferred stock	0	0
Common stock	105	102
Additional paid-in capital	1,852,155	1,725,823
Accumulated other comprehensive loss	(539)	(10)
Accumulated deficit	(2,247,881)	(2,112,238)
Total stockholders' deficit	(396,160)	(386,323)
Total liabilities and stockholders' deficit	$ 808,082	$ 824,316

Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Reconciliation of Cash, Cash Equivalents, and Restricted Cash Equivalents


	March 31, 2024		December 31, 2023
Cash and cash equivalents	$	119,976	$	113,024
Restricted cash		375		375
Total cash, cash equivalents, and restricted cash as reported within our consolidated statement of cash flows	$	120,351	$	113,399

Summary of Accrued Liabilities

Accrued liabilities were as follows (in thousands):


	March 31, 2024		December 31, 2023
Accrued liabilities:
Clinical and preclinical costs	$	9,163	$	5,880
Compensation related		16,167		29,255
Other accrued expenses		14,793		7,506
Total accrued liabilities	$	40,123	$	42,641

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net loss	$ (135,643)	$ (131,289)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash interest expense on liabilities related to revenue participation right purchase agreements	10,244	6,313
Stock-based compensation expense	21,612	15,194
Non-cash lease expense	995	935
Depreciation of property and equipment	2,331	1,848
Realized gain on investment, net	0	34
Interest receivable and amortization on investments	(5,224)	(3,037)
Non-cash interest expense related to debt	1,879	6,888
Changes in operating assets and liabilities:
Accounts receivable	449	(859)
Prepaid and other assets	(6,630)	(1,627)
Accounts payable	(10,294)	(8,106)
Accrued and other liabilities	(5,579)	(7,755)
Operating lease liabilities	(1,712)	(120)
Other non-current liabilities	(1,935)	(705)
Net cash used in operating activities	(129,507)	(122,286)
Cash flows from investing activities:
Purchases of investments	(142,655)	(89,779)
Maturities of investments	175,296	250,701
Sales of investments	0	4,977
Purchases of property and equipment	0	(402)
Net cash provided by (used in) investing activities	32,641	165,497
Cash flows from financing activities:
Repayment of finance lease liabilities	(227)	(207)
Repayment of term loan	(705)	0
Proceeds from issuance of common stock related to at-the-market offering, net of issuance costs	93,640	0
Proceeds from issuance of common stock under equity incentive and stock purchase plans	29,532	3,547
Taxes paid related to net share settlement of equity awards	(18,449)	(10,517)
Net cash provided by financing activities	103,791	(7,177)
Effect of exchange rate changes	27	0
Net increase (decrease) in cash, cash equivalents, and restricted cash	6,952	36,034
Cash, cash equivalents, and restricted cash, beginning of period	113,399	67,182
Cash, cash equivalents, and restricted cash, end of period	120,351	103,216
Supplemental cash flow disclosures:
Cash paid for interest	10,206	40
Non-cash investing and financing activities:
Right-of-use assets recognized in exchange for operating lease obligations	178	0
Amounts unpaid for purchases of property and equipment	$ 1,754	$ 473

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2024	May 08, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Trading Symbol	CYTK
Entity Registrant Name	CYTOKINETICS, INCORPORATED
Entity Central Index Key	0001061983
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	000-50633
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	94-3291317
Entity Address, Address Line One	350 Oyster Point Blvd
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	624-3000
Entity Common Stock, Shares Outstanding		104,853,918
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Document Quarterly Report	true
Document Transition Report	false

Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Credit losses on debt securities	$ 0	$ 0

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Instruments Excluded from the Computation of Diluted Net Loss Per Share

The following instruments were excluded from the computation of diluted net loss per share for the periods presented because their effect would have been antidilutive (in thousands):


	March 31, 2024		March 31, 2023
Options to purchase common stock		11,095		12,362
Warrants to purchase common stock		—		13
Restricted stock and performance units		1,692		1,438
Shares issuable related to the ESPP		65		49
Shares issuable upon conversion of 2026 Notes		2,003		2,003
Shares issuable upon conversion of 2027 Notes		10,572		10,572
Total shares		25,427		26,437

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2024

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Options and Restricted Stock Units Granted

Our annual grant of stock-based compensation takes place during the first quarter of each year. Our stock options and restricted stock units granted for the first quarter of 2024 was as follows:


	Grants		Weighted Average Grant Date Fair Value per Share
Stock options		932,778	$	64.54
Restricted stock units		1,037,398	$	63.77

Summary of Warrants Outstanding to Purchase Shares of Common Stock

As of December 31, 2023, we had the following warrants outstanding to purchase shares of our common stock which were exercised in January 2024:


Issuance Date	Expiration Date	Exercise Price		Warrants Outstanding at December 31, 2023		Warrants Outstanding at March 31, 2024		Warrants Exercised during the Three Months Ended March 31, 2024		Common Shares Issued upon Exercise of Warrants
January 2020	January 2030	$	10.42		12,957		—		12,957		11,335

Agreements with Royalty Pharma - Schedule of Initial Consideration (Detail) - 2022 Royalty Pharma Transactions [Member] $ in Thousands	Jan. 07, 2022 USD ($)
Debt Instrument [Line Items]
Consideration Fair Value	$ 116,385
Consideration proceeds	150,000
Consideration allocation	150,000
Revenue Participation Right Purchase Agreements [Member]
Debt Instrument [Line Items]
Consideration Fair Value	69,498
Consideration proceeds	100,000
Consideration allocation	89,571
Development Funding Loan Agreement [Member]
Debt Instrument [Line Items]
Consideration Fair Value	46,887
Consideration proceeds	50,000
Consideration allocation	$ 60,429

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Fair Value Measurements - Summary of Fair Value of Financial Assets Consists of Cash Equivalents and Investments Classified as Available-for-sale Securities Measured on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - Cash and Cash Equivalents and Investments [Member] - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 627,535	$ 632,695
Unrealized Gains	43	359
Unrealized Losses	(588)	(349)
Fair Value	626,990	632,705
Money Market Funds [Member] \| Fair Value Measurements Using Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	108,635	77,429
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	108,635	77,429
U.S. Treasury Securities [Member] \| Fair Value Measurements Using Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	60,920	34,625
Unrealized Gains	0	13
Unrealized Losses	(46)	(15)
Fair Value	60,874	34,623
U.S. Government agency securities \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	104,159	175,301
Unrealized Gains	11	87
Unrealized Losses	(149)	(133)
Fair Value	104,021	175,255
Commercial Paper [Member] \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	239,642	252,956
Unrealized Gains	18	156
Unrealized Losses	(229)	(59)
Fair Value	239,431	253,053
Corporate Obligations [Member] \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	114,179	92,384
Unrealized Gains	14	103
Unrealized Losses	(164)	(142)
Fair Value	$ 114,029	$ 92,345

Organization and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Cytokinetics, Incorporated was incorporated under the laws of the state of Delaware on August 5, 1997. The Company is a late-stage biopharmaceutical company focused on the discovery and development of novel small molecule therapeutics that modulate muscle function for the potential treatment of serious diseases and medical conditions. Our financial statements contemplate the conduct of our operations in the normal course of business. We have incurred an accumulated deficit of approximately $2.2 billion since inception and there can be no assurance that we will attain profitability. We had a net loss of $135.6 million and net cash used in operations of $129.5 million for the three months ended March 31, 2024. Cash, cash equivalents, and investments decreased to $634.3 million as of March 31, 2024 from $655.4 million as of December 31, 2023. We anticipate that we will have operating losses and net cash outflows in future periods. We are subject to risks common to late-stage biopharmaceutical companies including, but not limited to, development of new drug candidates, dependence on key personnel, and the ability to obtain additional capital as needed to fund our future plans. Our liquidity will be impaired if sufficient additional capital is not available on terms acceptable to us. To date, we have funded operations primarily through sales of our common stock, contract payments under our collaboration agreements, sales of future revenues and royalties, debt financing arrangements and interest income. Until we achieve profitable operations, we intend to continue to fund operations through payments from strategic collaborations, additional sales of equity securities, grants and debt financings. We have never generated revenues from commercial sales of our drugs and may not have drugs to market for at least several years, if ever. Our success is dependent on our ability to enter into new strategic collaborations and/or raise additional capital and to successfully develop and market one or more of our drug candidates. We cannot be certain that sufficient funds will be available from such a financing or through a collaborator when required or on satisfactory terms. Additionally, there can be no assurance that our drug candidates will be accepted in the marketplace or that any future products can be developed or manufactured at an acceptable cost. These factors could have a material adverse effect on our future financial results, financial position and cash flows. Based on the current status of our research and development activities, we believe that our existing cash, cash equivalents and investments will be sufficient to fund cash requirements for at least the next 12 months after the issuance of this Quarterly Report on Form 10-Q. If, at any time, our prospects for financing our research and development programs decline, we may decide to reduce research and development expenses by delaying, discontinuing or reducing our funding of one or more of our research or development programs. Alternatively, we might raise funds through strategic collaborations, public or private financings or other arrangements. Such funding, if needed, may not be available on favorable terms, or at all. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.
Basis of Presentation	Basis of Presentation Our condensed consolidated financial statements include the accounts of Cytokinetics and our wholly-owned subsidiaries. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The financial statements include all adjustments (consisting only of normal recurring adjustments) that management believes are necessary for the fair statement of our financial information. These interim results are not necessarily indicative of results to be expected for the full fiscal year or any future interim period. The balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by GAAP for complete financial statements. The financial statements and related disclosures have been prepared with the presumption that users of the interim financial statements have read or have access to the audited financial statements for the preceding fiscal year. Accordingly, these financial statements should be read in conjunction with the audited financial statements and notes thereto contained in the Company’s Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. We evaluate our estimates on an ongoing basis. We base our estimates on our historical experience and also on assumptions that we believe are reasonable; however, actual results could significantly differ from those estimates
Recent Accounting Pronouncements	Recently Issued Accounting Pronouncements In November 2023, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This standard requires disclosure of significant segment expenses and other segment items by reportable segment. The ASU becomes effective for annual periods beginning in 2024 and interim periods in 2025. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This standard enhances disclosures related to income taxes, including the rate reconciliation and information on income taxes paid. The ASU becomes effective January 1, 2025.

Debt - Additional Information (Detail)			3 Months Ended
Debt - Additional Information (Detail)	Jul. 06, 2022 USD ($) $ / shares shares	Nov. 13, 2019 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) Days	Mar. 31, 2023
Debt Instrument [Line Items]
Principal amount of original loan			$ 561,132,000
2026 Notes [Member]
Debt Instrument [Line Items]
Principal amount of original loan		$ 138,000,000	21,132,000
Issuance of shares of common stock \| shares	8,071,343
Repurchase of principal amount of original loan	$ 116,900,000
Aggregate principal amount remaining			$ 21,100,000
Number of instalments description			payable semiannually in arrears on January 1 and July 1 of each year, beginning on January 1, 2023
Convertible notes, maturity date		Nov. 15, 2026
Convertible debt, fair value			$ 141,700,000
Convertible notes, interest rate		4.00%
Convertible notes, sinking fund		$ 0
Convertible notes, shares issued \| shares		94.7811
Convertible notes, principal amount		$ 1,000
Convertible notes, initial conversion price \| $ / shares		$ 10.55
Convertible notes, type of equity security issued		common stock
Convertible notes, percentage of conversion price			130.00%
Convertible notes, trading days \| Days			20
Convertible notes, consecutive trading days \| Days			30
Convertible notes, redemption description			The 2026 Notes are redeemable, in whole or in part, at our option at any time, and from time to time, and, in the case of any partial redemption, on or before the 60th scheduled trading day before the maturity date, at a cash redemption price equal to the principal amount of the 2026 Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we may send the related redemption notice; and (ii) the trading day immediately before the date we may send such notice.
Debt instrument, unamortized debt issuance cost			$ 300,000
Unamortized debt discount amortization period			2 years 8 months 12 days
2026 Notes [Member] \| Liability [Member]
Debt Instrument [Line Items]
Debt instrument effective interest rate			4.60%	4.60%
2027 Notes [Member]
Debt Instrument [Line Items]
Principal amount of original loan	540,000,000		$ 540,000,000
Payment associated with convertible notes	$ 140,300,000
Aggregate principal amount remaining			$ 540,000,000
Number of instalments description			payable semi-annually on May 15 and December 15 of each year, beginning May 15, 2020
Convertible notes, maturity date	Jul. 01, 2027
Convertible debt, fair value			$ 866,600,000
Convertible notes, interest rate	3.50%
Convertible notes, shares issued \| shares	19.5783
Convertible notes, principal amount	$ 1,000
Convertible notes, initial conversion price \| $ / shares	$ 51.08
Convertible notes, type of equity security issued	common stock
Convertible notes, conversion description	Holders of the 2027 Notes have the option to convert their convertible notes only in the following circumstances: (i) if the last reported sale price per share of our common stock exceeds 130% of the conversion price for at least 20 trading days within a 30-day period starting from the last trading day of the preceding quarter after September 30, 2022; (ii) within 5 consecutive business days following any 10 consecutive trading day period if the trading price per $1,000 principal amount of 2027 Notes during such period falls below 98% of the product of the last reported sale price per share of our common stock and the conversion rate; (iii) upon certain corporate events or distributions on our common stock outlined in the 2027 Indenture; (iv) upon our call for redemption of the 2027 Notes; and (v) from March 1, 2027, until the scheduled trading day immediately preceding the maturity date. Circumstance (i) defined above was triggered upon the calculation completed for April 1, 2024.		The 2027 Notes are convertible into cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s). The initial conversion rate for the 2027 Notes is 19.5783 shares of our common stock per $1,000 principal amount of such Notes, which is equivalent to an initial conversion price of approximately $51.08 per share.
Convertible notes, redemption description			Consequently the 2027 Notes are redeemable at the option of the holders for the second quarter of 2024. This calculation will continue to be re-evaluated on a quarterly basis. We may not redeem the 2027 Notes at our option at any time before July 7, 2025. The 2027 Notes will be redeemable, in whole or in part (subject to the “Partial Redemption Limitation” (as defined in the 2027 Indenture)), at our option at any time, and from time to time, on or after July 7, 2025
Debt instrument, unamortized debt issuance cost			$ 11,000,000
Unamortized debt discount amortization period			3 years 3 months 18 days
2027 Notes [Member] \| Liability [Member]
Debt Instrument [Line Items]
Debt instrument effective interest rate			4.20%	4.20%
2027 Notes [Member] \| Debt Instrument Convertible Covenant One [Member]
Debt Instrument [Line Items]
Convertible notes, percentage of conversion price			130.00%
Convertible notes, trading days \| Days			20
Convertible notes, consecutive trading days \| Days			30
2027 Notes [Member] \| Debt Instrument Convertible Covenant Two [Member]
Debt Instrument [Line Items]
Convertible notes, percentage of last reported sale price of common stock			98.00%
Convertible notes, trading days \| Days			5
Convertible notes, consecutive trading days \| Days			10

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues:
Total revenues	$ 835	$ 4,613
Operating expenses:
Research and development	81,570	79,421
General and administrative	45,500	49,665
Total operating expenses	127,070	129,086
Operating loss	(126,235)	(124,473)
Interest expense	(7,103)	(6,961)
Non-cash interest expense on liabilities related to revenue participation right purchase agreements	(10,218)	(6,280)
Interest and other income, net	7,913	6,425
Net loss	$ (135,643)	$ (131,289)
Net loss per share - basic	$ (1.33)	$ (1.38)
Net loss per share - diluted	$ (1.33)	$ (1.38)
Weighted-average number of shares used in computing net loss per share - basic	101,924	95,164
Weighted-average number of shares used in computing net loss per share - diluted	101,924	95,164
Other comprehensive (loss) gain:
Unrealized (loss)/gain on available-for-sale securities, net	$ (556)	$ 1,945
Foreign currency translation adjustments	27	0
Comprehensive loss	(136,172)	(129,344)
Research and Development Revenues [Member]
Revenues:
Total revenues	835	2,113
Milestone Revenues [Member]
Revenues:
Total revenues	$ 0	$ 2,500

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	• Robert Blum, President & Chief Executive Officer – Mr. Blum adopted a Rule 10b5-1 trading arrangement on March 5, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Blum 2024 Plan”). The Blum 2024 Plan provides for the sale of (a) 62,233 shares of our common stock at market prices on the dates of the relevant sales and (b) the exercise of stock options to purchase up to 188,767 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Blum 2024 Plan will terminate on the earlier of (x) December 31, 2025 and (y) the sale of all securities that are subject to the plan. • Fady Malik, Executive Vice President, Research and Development – Dr. Malik adopted a Rule 10b5-1 trading arrangement on March 12, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Malik 2024 Plan”). The Malik 2024 Plan provides for the sale of (a) 27,492 shares of our common stock at market prices on the dates of the sale and (b) the exercise of stock options to acquire up to 74,322 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Malik 2024 Plan will terminate on the earlier of (x) December 13, 2024 and (y) the sale of all securities that are subject to the plan. • Andrew Callos, Executive Vice President, Chief Commercial Officer – Mr. Callos adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Callos 2024 Plan”). The Callos 2024 Plan provides for the sale of (a) 24,946 shares of our common stock at various limit prices on the dates of the sale and (b) the exercise of stock options to acquire up to 146,875 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Callos 2024 Plan will terminate on the earlier of (x) March 4, 2025 and (y) the sale of all securities that are subject to the plan. • Robert Wong, Vice President, Chief Accounting Officer – Mr. Wong adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Wong 2024 Plan”). The Wong 2024 Plan provides for the sale of (a) 13,011 shares of our common stock at market prices on the dates of the sale and (b) the exercise of stock options to acquire up to 70,000 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Wong 2024 Plan will terminate on the earlier of (x) September 30, 2024 and (y) the sale of all securities that are subject to the plan. • B. Lynne Parshall, Director, Chair of the Audit Committee – Ms. Parshall adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Parshall 2024 Plan”). The Parshall 2024 Plan provides for the exercise of stock options to acquire up to 40,000 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Parshall 2024 Plan will terminate on the earlier of (x) September 20, 2024 and (y) the sale of all securities that are subject to the plan. • Santo J. Costa, Director, Chair of the Compensation and Talent Committee – Mr. Costa adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Costa 2024 Plan”). The Costa 2024 Plan provides for the exercise of stock options to acquire up to 40,000 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Costa 2024 Plan will terminate on the earlier of (x) December 5, 2024 and (y) the sale of all securities that are subject to the plan. • Wendell Wierenga, Director, Chair of the Science and Technology Committee – Dr. Wierenga adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Wierenga 2024 Plan”). The Wierenga 2024 Plan provides for the exercise of stock options to acquire up to 20,000 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Wierenga 2024 Plan will terminate on the earlier of (x) May 9, 2025 and (y) the sale of all securities that are subject to the plan. • Edward M. Kaye, Director – Dr. Kaye adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Kaye 2024 Plan”). The Kaye 2024 Plan provides for the exercise of stock options to acquire up to 71,589 shares of our common stock and the concurrent sale of all shares of common stock acquired upon such exercise at various limit prices, in each case at pre-specified dates during the term of the plan. The Kaye 2024 Plan will terminate on the earlier of (x) March 4, 2025 and (y) the sale of all securities that are subject to the plan. • Muna Bhanji, Director – Ms. Bhanji adopted a Rule 10b5-1 trading arrangement on March 11, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Bhanji 2024 Plan”). The Bhanji 2024 Plan provides for the sale of 5,613 shares of our common stock at market prices on the date of the sale. The Bhanji 2024 Plan will terminate on the earlier of (x) July 24, 2024 and (y) the sale of all securities that are subject to the plan. • Robert Harrington, Director – Dr. Harrington adopted a Rule 10b5-1 trading arrangement on March 4, 2024 that was intended to satisfy the affirmative defense provided for under Rule 10b5-1(c) (the “Harrington 2024 Plan”). The Harrington 2024 Plan provides for the sale of 1,833 shares of our common stock at market prices on the date of the sale. The Harrington 2024 Plan will terminate on the earlier of (x) July 31, 2024 and (y) the sale of all securities that are subject to the plan. Certain of our officers have made elections to participate in, and are participating in, our employee stock purchase plan, which may be designed to satisfy the affirmative defense conditions of Rule 10b5-1 under the Exchange Act or may constitute non-Rule 10b5–1 trading arrangements. In addition, certain of our directors have made elections to participate in, and are participating in, our director equity in lieu of cash retainer option program (as described in the “Director Compensation” section of our Proxy Statement for our 2024 Annual Meeting), which may be designed to satisfy the affirmative defense conditions of Rule 10b5-1 under the Exchange Act or may constitute non-Rule 10b5–1 trading arrangements.
Robert Blum [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Fady Malik [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Andrew Callos [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Robert Wong [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
B. Lynne Parshall [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Santo J. Costa [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Wendell Wierenga [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Edward M. Kaye [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Muna Bhanji [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Robert Harrington [Member]
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	true
Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Trading Plan [Member] \| Robert Blum [Member]
Trading Arrangements, by Individual
Name	Robert Blum
Title	President & Chief Executive Officer
Adoption Date	March 5, 2024
Termination Date	December 31, 2025
Rule 10b5-1 Trading Plan [Member] \| Fady Malik [Member]
Trading Arrangements, by Individual
Name	Fady Malik
Title	Executive Vice President, Research and Development
Adoption Date	March 12, 2024
Termination Date	December 13, 2024
Rule 10b5-1 Trading Plan [Member] \| Andrew Callos [Member]
Trading Arrangements, by Individual
Name	Andrew Callos
Title	Executive Vice President, Chief Commercial Officer
Adoption Date	March 4, 2024
Termination Date	March 4, 2025
Rule 10b5-1 Trading Plan [Member] \| Robert Wong [Member]
Trading Arrangements, by Individual
Name	Robert Wong
Title	Vice President, Chief Accounting Officer
Adoption Date	March 4, 2024
Termination Date	September 30, 2024
Rule 10b5-1 Trading Plan [Member] \| B. Lynne Parshall [Member]
Trading Arrangements, by Individual
Name	B. Lynne Parshall
Title	Director, Chair of the Audit Committee
Adoption Date	March 4, 2024
Termination Date	September 20, 2024
Rule 10b5-1 Trading Plan [Member] \| Santo J. Costa [Member]
Trading Arrangements, by Individual
Name	Santo J. Costa
Title	Director, Chair of the Compensation and Talent Committee
Adoption Date	March 4, 2024
Termination Date	December 5, 2024
Rule 10b5-1 Trading Plan [Member] \| Wendell Wierenga [Member]
Trading Arrangements, by Individual
Name	Wendell Wierenga
Title	Director, Chair of the Science and Technology Committee
Adoption Date	March 4, 2024
Termination Date	May 9, 2025
Rule 10b5-1 Trading Plan [Member] \| Edward M. Kaye [Member]
Trading Arrangements, by Individual
Name	Edward M. Kaye
Title	Director
Adoption Date	March 4, 2024
Termination Date	March 4, 2025
Rule 10b5-1 Trading Plan [Member] \| Muna Bhanji [Member]
Trading Arrangements, by Individual
Name	Muna Bhanji
Title	Director
Adoption Date	March 11, 2024
Termination Date	July 24, 2024
Rule 10b5-1 Trading Plan [Member] \| Robert Harrington [Member]
Trading Arrangements, by Individual
Name	Robert Harrington
Title	Director
Adoption Date	March 4, 2024
Termination Date	July 31, 2024
Rule 10B51Trading Plan One [Member] \| Robert Blum [Member]
Trading Arrangements, by Individual
Aggregate Available	62,233
Rule 10B51Trading Plan Two [Member] \| Robert Blum [Member]
Trading Arrangements, by Individual
Aggregate Available	188,767
Rule 10B51Trading Plan Three [Member] \| Fady Malik [Member]
Trading Arrangements, by Individual
Aggregate Available	27,492
Rule 10B51Trading Plan Four [Member] \| Fady Malik [Member]
Trading Arrangements, by Individual
Aggregate Available	74,322
Rule 10b5-1 Trading Plan Five [Member] \| Andrew Callos [Member]
Trading Arrangements, by Individual
Aggregate Available	24,946
Rule 10b5-1 Trading Plan Six [Member] \| Andrew Callos [Member]
Trading Arrangements, by Individual
Aggregate Available	146,875
Rule 10b5-1 Trading Plan Seven [Member] \| Robert Wong [Member]
Trading Arrangements, by Individual
Aggregate Available	13,011
Rule 10b5-1 Trading Plan Eight [Member] \| Robert Wong [Member]
Trading Arrangements, by Individual
Aggregate Available	70,000
Rule 10b5-1 Trading Plan Nine [Member] \| B. Lynne Parshall [Member]
Trading Arrangements, by Individual
Aggregate Available	40,000
Rule 10b5-1 Trading Plan Ten [Member] \| Santo J. Costa [Member]
Trading Arrangements, by Individual
Aggregate Available	40,000
Rule 10b5-1 Trading Plan Eleven [Member] \| Wendell Wierenga [Member]
Trading Arrangements, by Individual
Aggregate Available	20,000
Rule 10b5-1 Trading Plan Twelve [Member] \| Edward M. Kaye [Member]
Trading Arrangements, by Individual
Aggregate Available	71,589
Rule 10b5-1 Trading Plan Thirteen [Member] \| Muna Bhanji [Member]
Trading Arrangements, by Individual
Aggregate Available	5,613
Rule 10b5-1 Trading Plan Fourteen [Member] \| Robert Harrington [Member]
Trading Arrangements, by Individual
Aggregate Available	1,833

Commitments and Contingencies

3 Months Ended

Mar. 31, 2024

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 9 — Commitments and Contingencies

Operating Leases

In July 2019, we entered into the Oyster Point Lease of office and laboratory space at a facility located in South San Francisco, California, and we entered into amendments to the Oyster Point Lease in 2020, 2021, 2022, and 2023. The Oyster Point Lease commenced on March 31, 2021 and has an expiration date of October 31, 2033.

Debt - Schedule of Future Minimum Payments under 2026 Notes and 2027 Notes (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Jul. 06, 2022	Nov. 13, 2019
Debt Instrument [Line Items]
2024 remainder	$ 10,295
2025	19,745
2026	40,878
2027	558,900
Future minimum payments	629,818
Less: Interest	(68,686)
Convertible notes, principal amount	561,132
Less: Debt issuance costs on the convertible notes	(11,342)
Net carrying amount of the convertible notes	549,790	$ 548,989
2026 Notes [Member]
Debt Instrument [Line Items]
2024 remainder	845
2025	845
2026	21,978
2027	0
Future minimum payments	23,668
Less: Interest	(2,536)
Convertible notes, principal amount	21,132			$ 138,000
Less: Debt issuance costs on the convertible notes	(317)
Net carrying amount of the convertible notes	20,815
2027 Notes [Member]
Debt Instrument [Line Items]
2024 remainder	9,450
2025	18,900
2026	18,900
2027	558,900
Future minimum payments	606,150
Less: Interest	(66,150)
Convertible notes, principal amount	540,000		$ 540,000
Less: Debt issuance costs on the convertible notes	(11,025)
Net carrying amount of the convertible notes	$ 528,975