Research and Development Arrangements	6 Months Ended
Jun. 30, 2026
Research and Development [Abstract]
Research and Development Arrangements	Note 4 — Research and Development Arrangements Collaboration for Commercialization of Aficamten in Greater China Effective December 17, 2024, Sanofi has an exclusive license to develop and commercialize aficamten in China and Taiwan (the "Sanofi License Agreement"). The total maximum development and commercial milestone payments achievable for development and commercial milestone events in the field of oHCM and nHCM are $160.0 million, of which we have already earned $10.0 million in 2024 and $15.0 million in 2025, following regulatory approval of MYQORZO by the National Medical Products Administration ("NMPA") in China and the FDA in the United States. We are also entitled to receive 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 Sanofi License Agreement will, unless terminated earlier, continue on a market-by-market basis until expiration of the relevant royalty term. Collaboration revenues for China were $0.8 million and $1.2 million for the three and six months ended June 30, 2026, respectively, related to certain development cost reimbursements, along with an insignificant amount of royalty revenue. Collaboration revenues were not material for the three and six months ended June 30, 2025. Accounts receivable from Sanofi was $0.4 million as of June 30, 2026 and $15.1 million as of December 31, 2025. Collaboration for Commercialization of Aficamten in Japan On November 19, 2024, we announced that we had entered into a collaboration and license agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, for the exclusive development and commercialization of aficamten in Japan, subject to certain reserved development rights of Cytokinetics to continue to conduct certain clinical trials (the "Bayer License Agreement"). License and milestone revenues from Bayer was none and $11.9 million for the three and six months ended June 30, 2026, respectively, and $64.3 million for the three and six months ended June 30, 2025. The amount recognized in the six months ended June 30, 2026 relates to the milestone achievement of the first commercial sale of MYQORZO in the United States. Milestones associated with the first dosing of aficamten to the first patient in Japan in a Phase 3 clinical trial in nHCM and in a Phase 3 clinical trial in oHCM were achieved in 2025 and recognized as revenue in 2025. The first dose of aficamten in Japan in a Phase 3 clinical trial in nHCM occurred in June 2025 and the first dose of aficamten in Japan in a Phase 3 clinical trial in oHCM occurred in August 2025. There are no outstanding receivables related to license and milestone revenues from Bayer as of June 30, 2026. The Company earned €10.0 million in the first quarter of 2026 and remains eligible to receive up to an additional €70.0 million upon achievement of development and commercial milestones. The Company is also eligible to receive up to an additional €490.0 million in commercial milestone payments upon the achievement of certain sales milestones, and tiered royalties on net sales of aficamten in Japan. Collaboration revenues from Bayer were $2.5 million and $4.7 million for the three and six months ended June 30, 2026, respectively, and $2.4 million and $3.9 million for the three and six months ended June 30, 2025, respectively, related to certain research and development cost reimbursements. We had accounts receivable from Bayer of $2.5 million as of June 30, 2026, and $2.6 million as of December 31, 2025. 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. Research Collaboration In May 2025, we entered into a research collaboration where we will reimburse our collaborative research partner for their research expenses. The reimbursement of research expenses was $1.5 million and $2.7 million for the three and six months ended June 30, 2026, respectively, which were recorded as research and development. There was no reimbursement of research expenses for the three and six months ended June 30, 2025. Subject to the terms of the agreement, our collaborative research partner may receive potential research, development and commercial milestone and royalty payments from us and we may develop and commercialize development candidates. As of June 30, 2026, the collaborative partner under this collaboration provided a data package, which resulted in the achievement of a specified preclinical development milestone. Accordingly, the Company has recorded a liability of $2.5 million in accrued liabilities on the condensed consolidated balance sheet in anticipation of paying the milestone in the third quarter of 2026.

Research and Development Arrangements

6 Months Ended

Jun. 30, 2026

Note 4 — Research and Development Arrangements

Collaboration for Commercialization of Aficamten in Greater China

Effective December 17, 2024, Sanofi has an exclusive license to develop and commercialize aficamten in China and Taiwan (the "Sanofi License Agreement"). The total maximum development and commercial milestone payments achievable for development and commercial milestone events in the field of oHCM and nHCM are $160.0 million, of which we have already earned $10.0 million in 2024 and $15.0 million in 2025, following regulatory approval of MYQORZO by the National Medical Products Administration ("NMPA") in China and the FDA in the United States. We are also entitled to receive 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 Sanofi License Agreement will, unless terminated earlier, continue on a market-by-market basis until expiration of the relevant royalty term.

Collaboration revenues for China were $0.8 million and $1.2 million for the three and six months ended June 30, 2026, respectively, related to certain development cost reimbursements, along with an insignificant amount of royalty revenue. Collaboration revenues were not material for the three and six months ended June 30, 2025. Accounts receivable from Sanofi was $0.4 million as of June 30, 2026 and $15.1 million as of December 31, 2025.

Collaboration for Commercialization of Aficamten in Japan

On November 19, 2024, we announced that we had entered into a collaboration and license agreement with Bayer Consumer Care AG, an affiliate of Bayer AG, for the exclusive development and commercialization of aficamten in Japan, subject to certain reserved development rights of Cytokinetics to continue to conduct certain clinical trials (the "Bayer License Agreement").

License and milestone revenues from Bayer was none and $11.9 million for the three and six months ended June 30, 2026, respectively, and $64.3 million for the three and six months ended June 30, 2025. The amount recognized in the six months ended June 30, 2026 relates to the milestone achievement of the first commercial sale of MYQORZO in the United States. Milestones associated with the first dosing of aficamten to the first patient in Japan in a Phase 3 clinical trial in nHCM and in a Phase 3 clinical trial in oHCM were achieved in 2025 and recognized as revenue in 2025. The first dose of aficamten in Japan in a Phase 3 clinical trial in nHCM occurred in June 2025 and the first dose of aficamten in Japan in a Phase 3 clinical trial in oHCM occurred in August 2025. There are no outstanding receivables related to license and milestone revenues from Bayer as of June 30, 2026.

The Company earned €10.0 million in the first quarter of 2026 and remains eligible to receive up to an additional €70.0 million upon achievement of development and commercial milestones. The Company is also eligible to receive up to an additional €490.0 million in commercial milestone payments upon the achievement of certain sales milestones, and tiered royalties on net sales of aficamten in Japan.

Collaboration revenues from Bayer were $2.5 million and $4.7 million for the three and six months ended June 30, 2026, respectively, and $2.4 million and $3.9 million for the three and six months ended June 30, 2025, respectively, related to certain research and development cost reimbursements. We had accounts receivable from Bayer of $2.5 million as of June 30, 2026, and $2.6 million as of December 31, 2025.

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.

Research Collaboration

In May 2025, we entered into a research collaboration where we will reimburse our collaborative research partner for their research expenses. The reimbursement of research expenses was $1.5 million and $2.7 million for the three and six months ended June 30, 2026, respectively, which were recorded as research and development. There was no reimbursement of research expenses for the three and six months ended June 30, 2025. Subject to the terms of the agreement, our collaborative research partner may receive potential research, development and commercial milestone and royalty payments from us and we may develop and commercialize development candidates.

As of June 30, 2026, the collaborative partner under this collaboration provided a data package, which resulted in the achievement of a specified preclinical development milestone. Accordingly, the Company has recorded a liability of $2.5 million in accrued liabilities on the condensed consolidated balance sheet in anticipation of paying the milestone in the third quarter of 2026.