Good afternoon, and welcome to Cytokinetics' First Quarter 2025 Conference Call. At this time, I would like to inform you that this call is being recorded. And all participants are in a listen-only mode. At the company's request, we will open the call to questions after the presentation. We will allow for only one question per participant. I will now turn the call over to Diane Weiser, Cytokinetics' Senior Vice President of Corporate Affairs. Please go ahead.

Good afternoon, and thanks for joining us on the call today. Robert Blum, President and Chief Executive Officer, will begin with an overview of the quarter and recent developments; Andrew Callos, EVP and Chief Commercial Officer will address commercial readiness activities for aficamten; Fady Malik, EVP of R&D, will provide updates related to the clinical development program for aficamten; Stuart Kupfer, SVP and Chief Medical Officer, will provide updates on clinical development on omecamtiv mecarbil and CK-586; Isaac Ciechanover, EVP Corporate Development and Chief Business Officer will provide an update on business development in the context of our corporate development; Sung Lee, EVP and Chief Financial Officer, will provide a financial overview of the past quarter and finally, Robert will review expected key milestones for the remainder of 2025. Please note that portions of the following discussion, including our responses to questions, contain statements that relate to future events and performance rather than historical facts and constitute forward-looking statements. Our actual results might differ materially from those projected in these forward-looking statements. Additional information concerning factors that could cause our actual results to differ materially from those in these forward-looking statements is contained in our SEC filings, including our current report regarding our first quarter 2025 financial results filed on Form 8-K that was furnished to the SEC today. We undertake no obligation to update any forward-looking statements after this call. And now I will turn the call over to Robert.

Thank you, Diane, and thanks to all for joining us on the call today. The first quarter provided a strong start to the year, laying a solid foundation for the increased momentum we're building as we approach a pivotal step towards potential commercialization. Our principal focus is on our new drug application for aficamten. As we disclosed last week, the FDA extended the PDUFA date for the NDA for aficamten for the oHCM to December 26, 2025, to provide additional time to conduct a full review of our proposed revisions. To be clear, we had a series of three meetings with the FDA ahead of our NDA submission for aficamten, during which we discussed a range of topics related to the content of our submission, including safety monitoring and risk mitigation strategies. These included a top-line meeting to review the results of SEQUOIA-HCM, a pre-NDA meeting to cover specific topics related to our submission, and a type B meeting during which we discussed strategies related to safety monitoring and risk mitigation in support of our NDA submission. Attending all three of these meetings were representatives from the Division of Cardiology and Nephrology as well as representatives from the Division of Risk Management within the Office of Surveillance and Epidemiology of the FDA. These interactions provided the opportunity to discuss in detail the data supporting the safety and intrinsic pharmacological properties of aficamten and how they may inform approaches to manage risk and gain insight into the FDA's perspectives on this matter. Given these interactions, we considered it reasonable to propose a distinct risk mitigation approach specific to aficamten and based on labeling and other tools, such as voluntary education materials. However, we understood from the FDA that the potential need for a REMS would be a focus of the Agency's review. We determined to take this approach because under the circumstances we thought it was reasonable given the profile of aficamten. However, as a contingency, we developed our distinct REMS proposal and we were well prepared to submit it if necessary during the NDA review. The FDA requested that we submit a REMS specific to its intrinsic properties, which we promptly provided. We recently learned from the FDA that our subsequent submission of the REMS constitutes a major amendment to the NDA and will now require a standard three-month extension to the original PDUFA Action Date. To remind you, we discovered and developed aficamten with the objective to advance it as a potential next-in-class cardiac myosin inhibitor. Based on its inherent characteristics, we evaluated it in preclinical and clinical studies to understand how its half-life, its rapid onset, its reversibility, as well as an optimized relationship between PK and PD could enable a uniquely convenient dosing regimen. We extensively studied its DDI profile to similarly ensure that it was enabling of a distinct clinical profile to support potential differentiation. We believe the results of our clinical studies, including SEQUOIA-HCM and FOREST HCM, support a potential label and risk mitigation profile that, if approved by the FDA, will differentiate aficamten. Nothing has changed in that regard. To confirm, no additional clinical data or studies were requested by the FDA. As we disclosed in an 8-K filing in March, during the first quarter, we completed a mid-cycle review with the FDA. During the meeting, the FDA confirmed that the Agency does not plan to convene an advisory committee meeting, which is consistent with prior communications to us, and that our late cycle meeting is expected to occur in June. While the PDUFA extension does delay the potential approval of aficamten, it does not change our confidence in its distinct benefit, risk, and pharmacological profile, nor does it change our expectation for a potentially differentiated label and risk mitigation profile upon potential approval. Given the FDA review of the NDA is ongoing, we do not intend to provide further color or detailed updates on our communications with the FDA. Moving on during the first quarter and recently, we also advanced regulatory activities outside of the US. In April, we received 120-day questions from the EMA regarding the MAA for aficamten in Europe, and we're now working to develop responses. I'm pleased to share that we believe we are on track for potential approval by the EMA in the first half of 2026. During the quarter, we also worked with Sanofi, our partner in China, to support the NDA review of aficamten with the NMPA, and overall we're encouraged by the steady progress of our regulatory interactions globally. Moving to other activities during the first quarter, we continue to dial up our commercial readiness not only in the US but also in Europe. As Andrew will elaborate, during the quarter, we made key strides on all commercial planning work streams. Yes, the PDUFA date extension will shift out certain elements of our commercial readiness, but we are moving forward with launch planning. In the first quarter, we also achieved meaningful milestones in our ongoing clinical trials program for aficamten. We're pleased to share today that we plan to report top-line results from MAPLE-HCM this month. If the results are positive, we believe these data may represent a potential label expansion opportunity for aficamten following an initial potential FDA approval in oHCM. In addition to oHCM, we're also focused on nHCM, in which there is a significant unmet need for effective treatments, and with increasing recognition and diagnosis of the condition, the market opportunity continues to grow. We're pleased to share today that ACACIA-HCM, our pivotal Phase III clinical trial of aficamten in nHCM, has completed enrollment in the first quarter, months ahead of schedule, enabling us to read out the top-line results in the first half of 2026. Fady will elaborate on this achievement as well as on additional updates to the trial guided by global regulatory feedback. As the prevalence rate of nHCM rises, we remain optimistic regarding the promise of aficamten in this population of underserved patients. As you know, aficamten for the treatment of both oHCM and nHCM represents the first potential new medicine arising from our specialty cardiology franchise, which also includes omecamtiv mecarbil and CK-586, each advancing in respective later-stage clinical trials in two different forms of heart failure. The progress we made in the first quarter reflects thoughtful planning, disciplined resource management, and a steadfast commitment to rigorous clinical research, all of which propel us towards our ambitious Vision 2030. And with that, I'll turn the call over to Andrew, please.

Thanks, Robert. In the first quarter, we continued to execute our commercial readiness planning and implementation. With a three-month extension to our PDUFA timeline, certain work streams will need to be adjusted. However, we are not losing our sense of urgency or launch readiness momentum. This year has been focused on building, implementing, and executing our go-to-market plans as we intend to keep building this momentum towards our revised December PDUFA date. During the first quarter, we initiated our Salesforce recruiting. Given the December PDUFA date, we'll be revising our Salesforce onboarding plan while maintaining our current recruiting schedule, which is off to a great start. To date, we have received several thousand applications, many from highly qualified Salesforce professionals, with the majority possessing abundant cardiology experience and existing relationships, giving us a strong talent base from which to identify top candidates for these positions. In late April, we held a virtual recruiting webinar for sales professional candidates that grew nearly 1,000 attendees. These figures indicate a high level of interest and how well-positioned we are to attract top talent and build a standout sales organization. In parallel, our work around sales operational planning continued, including analytics, targeting, incentive comp, as well as finalizing the sales training curriculum. We are also building our bespoke patient support program by integrating our strategic partners into a seamless patient-focused implementation. We also finalized the selection of our channel distribution partner and specialty pharmacy partners. During the quarter, we continued to refine our promotional launch campaign for HCPs and patients, accounting for the most recent market dynamics, ACP Advisory Boards, as well as primary market research testing. At the same time, our unbranded disease awareness campaign, ACM Beyond the Heart, continued. The ACP-focused awareness campaign directs HCPs to consider the broader ACM burden and practice whole person care. Likewise, the pacing campaign helps educate people living with HCM not just about the condition but about the holistic burden of HCM. We also maintained our engagement with payers and plan to continue educating them on the data from the clinical development program of aficamten, as well as the clinical and economic burden of HCM. In addition to the burden of disease, we expect to have several HEOR presentations at upcoming meetings to further characterize both oHCM and nHCM and deepen the understanding of the disease. An exciting milestone during the first quarter was our launch of EARTH-HCM, an online open-access interactive public health education tool developed in collaboration with leading academic institutions. Outside of our U.S. commercial planning, we advanced European commercial readiness activities in a gated manner, including hiring key leadership positions for marketing, finance, legal, compliance, and human resources. We also set up new regional entities in France and the U.K. with in-country leaders. During the quarter, we also validated our reimbursement strategy and country launch sequence, which, as we previously stated, begins with Germany in 2026, pending EMA approval. Finally, we began dossier preparation for HTA submission across multiple geographies. To summarize, we've made progress in our commercial readiness activities over the past quarter, and we'll continue to finalize a robust commercial framework to support the potential U.S. and European launches of aficamten. With that, I'll turn the call over to Fady to share updates on our ongoing clinical trial program for aficamten.

Thanks, Andrew. As Robert mentioned, we plan to report top-line results from MAPLE-HCM this month with a presentation of the primary results at a medical meeting later this year. We want to set expectations now for the top-line release to be qualitative as we do not want to jeopardize this presentation at a major medical meeting by disclosing details of the results. To remind you, MAPLE-HCM is a rigorously designed trial, randomizing patients to treatment with aficamten or metoprolol, each as monotherapy. While beta blockers are standard of care in HCM, their impact on exercise performance, symptoms, and LVOT gradients in structural HCM is not well characterized. At the same time, the impact of treatment with aficamten as a monotherapy on the same measures is important to understand to inform the implementation of cardiac myosin inhibitors into the standard of care. We look forward to the results of this head-to-head comparison of MAPLE-HCM as it may help differentiate the effect of aficamten on exercise capacity, symptoms, and cardiac structure and function, as well as safety and tolerability from the long-established standard of care metoprolol. We also have a few important updates to share regarding ACACIA-HCM. First, we're pleased to report that in the first quarter of 2025, nearly six months ahead of schedule, we completed patient enrollment for the primary cohort of this trial, which encompasses all sites in North and South America, Australia, Europe, China, and Israel. We randomized 516 patients in only 18 months, driven by high interest in participation that accelerated screening and enrollment through the end of 2024 and into early 2025. The primary cohort of ACACIA-HCM includes the regions originally designated for enrollment when we initiated the trial in 2023. However, alongside the collaboration and licensing agreement we entered into with Bayer for aficamten in Japan late last year, we also agreed to expand ACACIA-HCM to Japan, targeting a start in Q2 2025 to support its potential marketing authorization for nHCM. Given the primary cohort completed enrollment months ahead of schedule, we've divided ACACIA-HCM into two parts, the primary cohort and the Japan cohort, an approach supported by regulators in Japan. With the enrollment now completed in the primary cohort, we expect to share top-line results from that cohort in the first half of 2026. Early in the first quarter, we also embarked on updating the primary endpoint of ACACIA-HCM from a single primary endpoint of KCCQ clinical summary score, followed by a first secondary endpoint of exercise capacity, to a dual primary endpoint of change in KCCQ clinical summary score and a measure of exercise capacity, peak VO2, each measured as a change from baseline to week 36. This change was made to align the endpoints of the trial to feedback we received from regulators outside the U.S. and harmonize its interpretation globally. Prior to this change, CPET measurements were already being obtained for all patients, so this change does not alter the conduct of the clinical trial—it only elevates a measure of exercise performance from the first secondary endpoint to an additional primary endpoint. Given the brisk enrollment of ACACIA-HCM, we enacted this change knowing that we could also power the trial adequately by increasing the sample size from 420 to at least 500 patients to ensure each of the primary endpoints had 90% power at an alpha of 0.025 to detect a conservative clinically meaningful change. Compared to placebo for KCCQ, that’s 5 points. And for peak VO2, that’s 1.0 milliliter per kilogram per minute. To be clear, if either clinical endpoint that comprises the dual primary endpoint is statistically significant, ACACIA-HCM will be considered positive. In sum, we believe these changes maximize the chances of the success of this trial and will also satisfy regulatory requirements globally. As a reminder, in Cohort 4 of the Phase II trial, REDWOOD-HCM, we evaluated treatment with aficamten in nHCM in an open-label fashion and demonstrated improvements in KCCQ and NYHA functional class and an average reduction in NT-proBNP of 66%. The majority of patients achieved the highest dose offered at 50 milligrams, and there were no drug discontinuations due to low ejection fraction and few instances of LVEF less than 50%. These findings were replicated when patients transitioned into the open-label extension trial, FOREST-HCM. Importantly, ACACIA-HCM builds on this Phase II experience by using the same dosing approach with rapid attainment of target dose within eight weeks, refinements of the entry criteria, and careful patient selection based on echocardiographic review by HCM specialists. Although nHCM currently accounts for about one-third of the HCM population, it’s now being diagnosed at a much faster rate than oHCM. As a result, we anticipate that nHCM will comprise nearly half of all HCM diagnoses. If the results from ACACIA-HCM are positive, this would represent a significant opportunity to help this underserved patient population who currently have limited treatment options. To close out the update on our ongoing clinical trials program, enrollment in CEDAR-HCM is progressing, and we remain on track to complete enrollment in the adolescent cohort in the second half of this year. As you've heard in the first quarter, there's been strong progress advancing the ongoing clinical trial program for aficamten, which we believe will pave the way for multiple opportunities to reach more patients living with HCM worldwide. Now I'll turn it over to Stuart.

Thanks, Fady. I'm pleased to provide updates on our later-stage development programs. During the quarter, we continued conduct of AMBER-HFpEF, the Phase II clinical trial of CK-586 in patients with symptomatic heart failure with preserved ejection fraction of at least 60%. We continue to progress towards our goal of completing enrollment in the first two cohorts in the second half of this year. Approximately two million people with heart failure in the U.S. have an ejection fraction greater than or equal to 60%. Despite advances in care and broad use of standard care treatments, these patients often have a poor prognosis following heart failure hospitalization and a high rehospitalization rate that also drives up healthcare costs. The unmet need to deliver better options for patients is clear, and we believe AMBER-HFpEF will help elucidate whether a cardiac myosin inhibitor may benefit the subset of patients with heart failure and builds on our experience in non-obstructive HCM. We also continue to enroll in COMET-HF, the confirmatory Phase III clinical trial of omecamtiv mecarbil in patients with symptomatic heart failure with severely reduced ejection fraction less than 30%. We maintained progress in activating sites in the U.S. and convened a well-attended U.S. investigator meeting at the end of April. During the meeting, we were pleased to see a high level of investigator engagement, reflecting their recognition of the urgency of developing safe and effective treatments for this high-risk population and our motivation to enroll patients in the trial. Many of these investigators participated in GALACTIC-HF, the first Phase III trial of omecamtiv mecarbil. We expect to continue enrolling COMET-HF this year and complete enrollment in 2026. Our later-stage pipeline represents our next highest opportunity following aficamten with multiple opportunities to positively impact patients with adjacent cardiovascular diseases of high unmet need. With that, I'll pass it to Isaac.

Thanks, Stuart. In the first quarter, we participated in a Series B financing of Imbria Pharmaceuticals to support the advancement of ninerafaxstat for the treatment of nHCM. This deal represents our first equity investment in which we can participate in and advise on the development of a novel therapy in the cardiometabolic space that may be of interest to us in the future without committing significant financial or operational resources. As we've stated in our Vision 2030, external innovation and business development are key pillars of our growth strategy. Our current R&D pipeline has arisen entirely from internal discovery, and we see a significant opportunity to complement and enhance this foundation through investments, partnering, and licensing opportunities. By engaging selectively and prudently in opportunities to balance our own R&D activities by also externalizing innovation, we aim to gain access to additional novel science, expand into adjacent therapeutic areas, and ultimately accelerate the development of new therapies for patients. Importantly, we continue to be open to all strategic levers to remain the partner of choice and continue to be both a pioneer and leader in muscle biology. Now I'll hand it over to Sung.

Thanks, Isaac. We're pleased to report our first quarter of 2025 financial results. Starting with the balance sheet, we finished the first quarter with approximately $1.1 billion in cash, cash equivalents, and investments compared to $1.2 billion at the end of the fourth quarter of 2024. Cash, cash equivalents, and investments declined by approximately $132.2 million during the first quarter of 2025. R&D expenses for the first quarter were $99.8 million compared to $81.6 million for the same period in 2024. The increase was primarily due to advancing our clinical trials and higher personnel-related costs. G&A expenses for the first quarter of 2025 were $57.4 million compared to $45.5 million for the same period in 2024. The increase was primarily due to investments in commercial readiness activities and higher personnel-related costs. Net loss for the first quarter of 2025 was $161.4 million, or $1.36 per share, compared to a net loss of $135.6 million, or $1.33 per share for the same period in 2024. Turning to our financial guidance, we are maintaining our full-year 2025 financial guidance with GAAP operating expense expected to be between $670 million and $710 million. Stock-based compensation that is included in GAAP operating expense is expected to be between $110 million and $120 million. Excluding stock-based compensation from GAAP operating expense results in a range of $550 million to $600 million. While the guidance range remains unchanged, there are two dynamics that move expenses within the range meaningfully. First, the range incorporates the U.S. PDUFA date extension for aficamten, which we anticipate will drive a decrease in G&A expense, mainly due to the adjusted timing of launch expenses. Second, the range accounts for the acceleration and increased enrollment of ACACIA, our Phase III trial of aficamten in nHCM, which will increase R&D expense. Given the U.S. PDUFA date extension, we will continue to monitor the pace of pre-launch investments and update you accordingly. Our balance sheet continues to be a source of strength, and we are well-positioned to fund the potential launch of aficamten in the U.S. later this year and advance our pipeline. With that, I'll hand it back to Robert.

Thank you, Sung. The first quarter was marked by meaningful progress across our business. Given the uncertainties of the macro market we are operating within, we're pleased to be in an advantaged position with a strong balance sheet and cash position, reflecting thoughtful planning and preparation in 2024 that will allow us to execute on all of our key priorities in 2025. Looking ahead at the next several months, there’s a lot in store for our company, most importantly, the potential FDA approval of aficamten at the end of this year and our full transition then to becoming an integrated commercial biopharmaceutical company, but also the near-term top-line readout of MAPLE-HCM. With all of this moving forward, alongside continued conduct of multiple additional later-stage clinical trials as well as our ongoing research, our prospects remain bright as we advance our Vision 2030 based on our pioneering foundation in muscle biology. We're closer than ever to realizing the benefit of our science as may potentially impact the lives of patients living with diseases of muscle dysfunction. And now I'll recap our upcoming milestones. For aficamten, we expect to advance NDA review activities with FDA to support the potential U.S. approval of aficamten in the second half of this year. We expect to advance go-to-market strategies and prepare to commercially launch aficamten in the United States in the second half of this year, subject to approval by the FDA. We expect to continue go-to-market plans in Germany and expand commercial readiness activities in Europe in 2025 in preparation for potential approval by the EMA in the first half of 2026. We expect to coordinate with Sanofi to support the potential approval of aficamten in China, pending approval by the NMDA, and we expect top-line results from MAPLE-HCM this month. We also expect to report top-line results from the primary cohort of ACACIA-HCM in the first half of 2026 and begin enrollment of patients in the Japan cohort of ACACIA-HCM in this quarter. We expect to complete enrollment of the adolescent cohort in CEDAR-HCM in the second half of this year. For omecamtiv mecarbil, we expect to continue patient enrollment in COMET-HF through 2025 to enable completion of enrollment in 2026. For CK-586, we expect to complete enrollment of the first two patient cohorts in AMBER-HFpEF in the second half of this year. Lastly, for preclinical development and ongoing research, we expect to continue ongoing preclinical development as well as research activities directed to additional muscle biology-focused programs. Operator, with that said, we can now open the call up to questions, please.

And our first question will come from Sean McCutcheon from Raymond James. Your line is now open.

Good afternoon. Hey guys, thanks for the…Based on the failure of ODYSSEY and the BMS verbiage around obstructive HCM being different from non-obstructive, getting a lot of questions on what that means for ACACIA. Can you speak to how you designed ACACIA around the properties of aficamten to drive a higher probability of success and how you view the importance of pushing the CMI dose higher in non-obstructive disease given you were able to get the majority of patients on that 20-milligram dose in the first non-obstructive cohort?

Sure. I'll speak generally and then ask Fady to answer your specific questions. Firstly, as it relates to ACACIA-HCM, we're very excited about the fact that it completed enrollment ahead of schedule and with such enthusiastic participation around the globe. Please also understand that for taking the same dosing regimen forward into Phase III and going to centers where we believe there's already ample experience with aficamten, this gives us optimism for what may be ultimately the results from that study. You heard us referring to nHCM, both with regard to REDWOOD Cohort 4 and how it reads. We believe this is encouraging regarding what we should expect from testing the same hypothesis in Phase III. So we maintain our very optimistic views towards ACACIA. With that, I'll turn it over to Fady to answer the specific questions.

Yes. I think the points that Robert made are the important ones. When we designed ACACIA, we were able to base it very closely on what we had experienced in the Phase II study, Cohort 4 of REDWOOD-HCM. So the dosing is essentially the same, although we did implement a higher dose in ACACIA. We’ve seen that dose be very successfully deployed in FOREST. So those nHCM patients have the availability of the 20-milligram dose, and some of them are currently taking it. We've seen in REDWOOD very few treatment interruptions, no discontinuations for intolerance. These factors, I think, are crucial, as getting the right dosing regimen is often one of the most critical aspects in determining the success of a Phase III trial. Secondarily, we have confidence in the data that we saw in Phase II with regards to KCCQ and NYHA class improvement. We didn't analyze peak VO2 in Phase II, just as we didn't do that for SEQUOIA as well for the oHCM patients. However, we expect, with improvements in symptoms and functional class, to witness some improvement in peak VO2, and we're very well powered to see even a modest change in peak VO2. Lastly, we stayed with centers where we had much experience, with whom we had vetted carefully. We have a team that reviews every patient enrolled in the trial to ensure that the patients meet the entry criteria and that their imaging is consistent with what you would expect in HCM. For all those reasons, we're still very optimistic about the chances of success for ACACIA.

Our next question will come from Salim Syed from Mizuho. Your line is open.

Great. Hey, Robert, good afternoon. Thanks for the question and all the color today. So I guess I'll just ask the obvious question here on aficamten. I just want to be clear. So did the FDA initially guide you to not submit the REMS? And then what happened? Was it something internal at the FDA? Or was there something in the package that caused them to change their stance? If you could provide some color around that.

Sure. I understand you want to get more detail. I'll share with you what I can, but please understand I may be very selective in my language. As you probably know well, when you have these interactions with the FDA ahead of an NDA submission, they give you feedback in response to questions. And as you've probably read in the summary basis of approval for mavacamten, the FDA guided for the submission of a REMS prior to its occurring. In our case, that did not happen. We discussed safety risk mitigation. Based on that discussion, we believed it was reasonable to proceed with the submission without a REMS. It was not an omission. We understood very well the feedback that we were receiving, and we elected to proceed with the submission without a REMS. It was accepted by the FDA without a REMS. During the review itself, however, the FDA notified us that they would like to see us submit a REMS. We can't know all that was going on within the FDA that prompted their desire to see a REMS. As you know, there's a lot going on around in the FDA. But we do know that we were well prepared for that scenario where the FDA would consider that a REMS would be appropriate. We submitted the REMS as they requested, distinct to the intrinsic properties of aficamten. So I think that's going to have to suffice for what we can share. We don’t want to communicate things that would be deemed speculation because we do not know all that contributed to the FDA's request. But I've shared with you what we know and the determination we made based on the feedback we received.

Our next question comes from Gena Wang from Barclays. Your line is open.

Good afternoon, this is Gena Wang from Barclays. So maybe, Rob, just follow your comments. Can you tell us whether the REMS program you submitted to the FDA was consistent with the one you shared with the investors? And also, given this unfortunate event, can you take advantage of it since there is only one time extension for the PDUFA? And FDA cannot extend twice. Can you use the MAPLE data and try to submit the MAPLE data to be included in the label for the December 26 approval?

So I'll answer the second question first. We do not intend to submit the MAPLE data as part of this review cycle of aficamten in oHCM. That would constitute a different submission that would likely not be well received by the FDA given how far along they are in this review. If positive MAPLE results are obtained later this quarter, we do intend to move swiftly to enable a subsequent submission, but that would follow a potential approval of aficamten in oHCM. As for your first question, I would like some clarification, please. You asked whether the REMS we submitted is consistent with something we shared with investors.

Like the previous communication that will be like, say, the frequency will be week two until week eight. I'm trying to pull out the actual information that you shared in the past with investors. So just wondering, have you — and then also minimum like the certain monitoring protocol, was that consistent with what you proposed that you think will be differentiating from Camzyos' REMS program?

Yes. Please also understand that in the interest of maintaining a competitive advantage, we're not going to provide specific information regarding the REMS we submitted, but I will ask Fady to elaborate in a general way about how we're approaching safety and risk mitigation.

Yes. Gena, I think what we submitted is consistent with what we've said all along regarding the differentiated properties of aficamten. So as we did in FOREST, we amended the protocol to enable every six months monitoring, to widen the dosing window from every two weeks to every two to six or eight weeks to enable physicians to guide dosing directly. We've been straightforward in presenting those data recently to the American College of Cardiology. We do not have any clinically common drug-drug interactions. You can expect all those features would have gone into the design of a REMS program that we think will be distinct and well-received by physicians that treat these patients.

Our next question will come from Paul Choi from Goldman Sachs. Your line is open.

Hey, Robert. Good afternoon, everyone. Thanks for taking the question. Robert, earlier, you said aficamten will be differentiated, but maybe just to continue on what Fady was saying, with the recent changes to the Camzyos label, removing some of the drug-drug interaction warnings as well as the extended monitoring, increasing the monitoring period to six months. So I guess a lot of investors are just wondering what’s sort of left on the table for aficamten to be differentiated here. If you could offer any additional points here to help clarify that, that would be helpful.

Sure. Again, in a general way without specifics, I will correct the statement you made as it relates to drug-drug interactions, and as it relates to echo monitoring. There were modifications made to the existing Camzyos REMS, but still, there are limitations as it relates to drug-drug interactions. Similarly, there are limitations as it relates to echo monitoring, certainly during the up-titration phase, but also during the maintenance phase as it pertains to certain patients. So I would answer your question as follows: There remains ample opportunity for differentiation based on the REMS that we have submitted.

Our next question will come from Cory Kasimov from Evercore. Your line is open.

Hey, Robert. Hey, guys. Thanks for taking the question. My question is, did you submit a REMS as part of your EMA filing? And if not, was that brought up as part of your day 120 list of questions?

So there is no REMS per se as part of an MAA filing with the EMA. However, there are ways to ensure safe use and mitigate risk. I'll turn it over to Fady, maybe to elaborate.

Yes, EMEA approaches it differently. They do not have a REMS program per se. They do ask you to submit a risk mitigation program or RMP as a standard part of any submission, which we did. We don’t expect any changes, if you will, no additional submissions in Europe relating to that. It is very different from the way it's approached in the United States.

But to the point of your question, for now, we received the day 120 questions and are proceeding to respond. We believe we're well-served by what we submitted.

And our next question will come from Roanna Ruiz from Leerink Partners. Your line is open.

Hey, everyone. Afternoon. So a question on the ACACIA trial. Can you talk a bit more about the pros and cons of changing the primary endpoint to a dual primary of peak VO2 in KCCQ? And I was also curious if you could share more details of the current statistical plan for ACACIA if you're able to share with the dual primary endpoint, that would be really helpful.

Before I ask Fady to answer, I'll just say, I think as I look at this, this gives us two opportunities to win with ACACIA and building off of what we've seen with aficamten, both in oHCM and in REDWOOD Cohort 4, which is encouraging in light of how we proceeded in the design and conduct of ACACIA. And maybe Fady can go into more detail with you.

Yes. When we designed ACACIA, one of the important characteristics was to make it as efficient a trial as possible. Initially, nobody really knew how an HCM trial would enroll or how quickly it would enroll. Consequently, the most efficient thing to do was to declare a single primary endpoint and assign all the alpha to it. Your secondary endpoint can be your next most important endpoint. If the first one is positive, then all the alpha, the 0.05, flows to the second endpoint. That was an approach that was endorsed by the FDA. However, other regulators did not have the same appreciation of that as the FDA did. As we got advice in Europe and Japan, they were much more insistent on the imposition of a dual primary endpoint with two components, one being KCCQ and the other being peak VO2. We eventually engaged the change, knowing that we could power the trial adequately by increasing the sample size from 420 to at least 500 patients to ensure each of the primary endpoints had 90% power at an alpha of 0.025 to detect a conservative clinically meaningful change. We believe these changes position us for meeting regulatory requirements globally, while both endpoints being powered at 90% would allow us to assess KCCQ and peak VO2 simultaneously. In summary, it puts us in the best possible position to satisfy regulators and doesn't change the trial's interpretation, which requires consistency between symptoms and exercise performance.

Our next question comes from Zaki Molvi from Jefferies. Your line is open.

Hey, this is actually Akash. So a couple of things. What would you have to show with the FDA in real-world data to potentially get a yearly echo requirement over time? Is that a discussion you've already had with the agency? And then just to be clear, is Cytokinetics confident that a differentiated REMS for aficamten means an educational REMS and not an ETASU one?

Sure. Again, please understand that we will not answer all of the specific questions relating to elements of differentiation within the REMS itself. So your question about echo monitoring frequency is ideally best translated elsewhere. What I will say is it’s reasonable for us to be assuming an ETASU REMS. That's the approach we're taking.

And our next question will come from Charles Duncan from Cantor. Your line is open.

Hello, Charles. Good afternoon. Hey Robert. Good afternoon. Thanks for taking the question. Congrats on the progress. I do have what I'll call a multipart question, and that is the same subject. Regarding MAPLE-HCM, respect the strategy with regard to the FDA. But are you thinking about the same type of strategy with regard to submitting MAPLE after the fact for the EMEA as well as in China to the NMPA? And if so, why?

Good question. I will turn that to Fady, please.

Yes. I think the answer really is the same in all jurisdictions. Adding MAPLE-HCM to applications that are already well into review would be quite disruptive, so we don't plan to do that. We intend to submit the following approvals in those jurisdictions.

Our next question comes from Tessa Romero from JPMorgan. Your line is open.

Hello, Tess. Thank you. Good afternoon. Did the FDA indicate at any point during these three meetings that you outlined before your NDA was filed that they did not think that a REMS would be necessary? And why didn't you disclose that there was no REMS submitted back when you submitted the NDA? And when exactly did the FDA request the REMS?

I'll do my best to answer the questions. I prefer not to communicate what the FDA told us, as that is for the FDA to communicate. What I can communicate is how we determined, based on FDA feedback, what we should do. That is what we're communicating today. If aficamten is ultimately approved, then I expect in a summary basis of approval, this will all be laid out for you to understand. However, I hope you can appreciate that we continue to have ongoing interactions with the FDA, and I don’t think it would make sense for us to let this play out publicly in such a way that the FDA might ultimately be concerned. That’s number one. Secondly, you asked when we received this information. We received it promptly, around the time that we communicated that we made this decision, and we communicated the feedback from the FDA regarding the amendment. I hope that answers your questions.

You did. I'm just curious why a disclosure wasn't made back when you submitted the NDA that there was no REMS that was submitted.

Because that would be unconventional, and potentially detrimental to our competitive advantage. We didn't think that was information that required disclosure. Instead, because we did not submit a REMS, we were disciplined about what we were saying, believing that, upon approval, aficamten would carry a differentiated safety and risk mitigation profile. You'll note that we did not specify with or without REMS. Only upon asking for us to submit a REMS did we then proceed to do so, changing how we communicated about our expectations for differentiation.

Our next question comes from Maxwell Skor from Morgan Stanley. Your line is open.

Great. Thank you for taking my question. Given that the Camzyos REMS was updated recently, you submitted a 120-day safety update from the FOREST trial. I'm just wondering whether the REMS you recently submitted to the FDA potentially differs from what you would have submitted with the initial filing or discussed during your pre-NDA meetings.

This is a very fluid situation. What we might have submitted had we submitted a REMS in 2024 is speculative, and I prefer not to go there. What I will say is that we have been monitoring closely not only our conversations with the FDA but also how the FDA approached the modification of the REMS program for Camzyos. We believe we've submitted a REMS that would enable a differentiated, distinct profile.

Our next question comes from Leonid Timashev from RBC. Your line is open.

Hey, thanks for taking my question. I forgot to give you guys a break from the REMS discussion. I was just curious about nHCM. Obviously, with only one drug potentially going to be approved in the near term, yours, how are you thinking about what that means for potential uptake of aficamten in nHCM if it's approved? I mean, would you expect more patient warehousing and therefore, more rapid launch? Or would you have preferred someone building out that market? And then I guess on EU versus U.S., and you've talked about 50% of patients ultimately coming from nHCM. Is that dynamic just for the U.S. or both internationally as well?

Good questions. I'm going to turn to Andrew Callos to answer those, please.

Sure. From an nHCM point of view, the diagnosis rate is increasing pretty dramatically. I think when you do market development for HCM, it's not restricted to obstructive HCM. It's really broader for the disease. So when we look at uptake for nHCM, I would expect that nHCM uptake would be faster than oHCM because of all the market development work, because of physician utilization of CMIs, as well as expansion beyond the current prescribing base. So we're already thinking with MAPLE, with the properties of aficamten, that we can expand beyond the centers of excellence. I think that would get accelerated with MAPLE and further increased with ACACIA, and there will likely be a halo effect in terms of utilization across both obstructive and non-obstructive if both MAPLE and ACACIA are positive.

And our next question will come from David Lebowitz from Citi. Your line is open.

Thank you very much for taking my question. Could you characterize the nature of the market opportunity presented by MAPLE, given that while beta blockers might not necessarily be the most effective, they are cheap and they're prescribed by a wider array of doctors?

We've been consistent in believing that if MAPLE were positive and that is reflected in guidelines, this would be incremental but not transformative to what we believe could be the adoption curve for aficamten. It might enable more category penetration, especially amongst cardiologists who may be very comfortable with beta blockers. Andrew has done some market research here, and he may have more to add.

Yes. That’s right. The second data set that, assuming it’s positive, would confirm efficacy and safety would ultimately allow the guidelines to increase penetration within the use of CMIs. More physicians with more patients will use a CMI than would without MAPLE. There’s increased share potential for aficamten as well. You really get all those things collectively when you have a second data set around the same disease area. From our research, it’s going to enable broader penetration into the community cardiology.

If the results are positive, and we hope they are, then we can conduct further market research around that particular profile, and that may inform how we may communicate down the road.

Our next question will come from Mayank Mamtani from B. Riley Securities. Your line is now open.

Good afternoon. Thanks for taking our questions. Two quick process questions really. Could you touch on your confidence level in this newly submitted REMS to be accepted as is? And what sort of communication can we expect from you following up to the June late-cycle meeting that is coming up? And just at a high level, do you sense independent physician feedback, say, in the form of an Adcom, is something that could be valuable here for the agency and the community, particularly since you would have MAPLE-HCM data by then to discuss that clear API differentiation?

I believe that was three questions, and I'm going to try to remember now the first one. I think you asked if I thought the REMS as submitted would be accepted as is. These things are never exactly as they are submitted, there’s always back and forth. We do believe it's for that reason that the FDA chose to make the submission a major amendment, but we believe there’s ample time to address those matters within now the extended timeline. I know your third question related to the Adcom. Based on communications we've received from the FDA, we're expecting that to occur in the second quarter in June.

I mean, you'd have more data to share in a public forum about the drug's profile, especially the treatment initiation phase with echo monitoring. Therefore, could the agency benefit from having that independent physician feedback in a forum like that?

As we've stated before, the choice to have an Adcom or not rarely, if ever, pivots around elements that are included in a REMS. They don't typically have expertise among advisers who populate an Adcom pertaining to REMS, as they look at risk mitigation at the FDA. So that would be quite an irregular type of Adcom. I don't foresee that's something that investors or analysts should anticipate.

And our next question will come from Kripa Devarakonda from Truist. Your line is open.

Hey guys, thank you so much for taking my question. Robert, sorry to belabor the REMS point, but I just want to make sure I understood it correctly. You said you did not receive any guidance from FDA to submit REMS, whereas mavacamten they did receive guidance. But you also said that during these meetings, the three meetings that you talked about, they give feedback in response to questions. So, based on what you're saying, is it fair to assume that you asked the FDA if you should submit the REMS? And then, based on the feedback, you concluded that it was fair not to submit the REMS program?

I think that is correct.

Our next question will come from James Condulis from Stifel. Your line is open.

Thanks for sneaking me in. And sorry for one more question on the REMS here. So it sounds like the ask from the FDA kind of came after the mid-cycle review. I guess, is that right? I'm just wondering if there's any color on sort of that mid-cycle review that you can give in terms of discussions around the need for the REMS or lack of that. And just kind of curious if there's any color you can provide.

I think we provided most of the color that we can with the information we shared. We did issue an 8-K after the mid-cycle review meeting. We indicated that we submitted a REMS, and we got back feedback upon receipt that it constitutes a major amendment. That’s all that we can communicate at this time, and I hope that suffices.

Our next question comes from Jason Zemansky from Bank of America.

I apologize; I do want to return to the REMS. Just given everything that's happened, I know you are reluctant to discuss what the FDA has said, but focusing in on the Cytokinetics side of things, given that the REMS has been such a focal point and it was a big matter in mavacamten's review, why not just include the REMS initially and then work around it? It seems like this was a risk hindsight being 20/20 that was sort of always out there.

I would agree with you that it was a risk that was out there. It was a calculated one, and we made a determination based on multiple meetings with the FDA. We not only have substantial expertise within Cytokinetics but also convened with consultants, including ex-FDA officials on this matter. Collectively, we all concluded that the way we approached the submission without a REMS was reasonable. We addressed feedback we received regarding labeling and risk mitigation without including a REMS in that submission. The NDA was accepted for filing without a REMS, and as we understood it was an option during the FDA's review, they requested a REMS, which we were prepared to submit. We believe this approach was reasonable for positioning aficamten as a distinctive and capable product while managing safety and risk through labeling.

Our next question comes from Leland Gershell from Oppenheimer. Your line is open.

Thanks very much. I'm actually going to ask a non-REMS question. Robert, I just want to ask in terms of any real-world studies that you may be performing after presumptive aficamten approval of the 24-week SEQUOIA data, will you be looking to collect real-world data that may further flesh out or delineate the benefit to septal reduction surgery for patients who are treated?

The FOREST study continues to enroll, and the conduct of that study continues to support what we believe to be a distinct profile for aficamten. You'll see more of that data this year. While this wasn't a specific question of yours, I believe this data is supportive of aficamten as potentially enabling us to maintain an exceptional profile. I’ll ask Fady to address your specific question about septal reduction.

Yes. In SEQUOIA, we conducted an analysis of patients qualified for septal reduction therapy and showed essentially that treatment with aficamten reduces that need by 90%. Ninety percent of patients were no longer eligible for it. We've seen that reflected in FOREST as well. As we look at the longer-term experience in FOREST, even with patients that didn't initially qualify, we can begin to compare those data with real-world registries and evaluate the progression of event rates, comparing those to perhaps other data points. We anticipate seeing that aficamten potentially slows those rates in the long run, which will enhance our conviction that aficamten is a cardiac myosin inhibitor with a disease-modifying mechanism.

Our next question comes from Jason Butler from Citizens JMP. Your line is open.

Hi, thanks for taking the question. Just wanted to switch gears here at the end and ask a question about CK-586 in the AMBER study. Just I guess two parts. One, can you give us color on how you plan to disclose data from the first two cohorts? But I guess more importantly, how should we think about these first two doses in terms of being effective doses or when we would expect to see something that's optimally effective out of the study?

I'll turn to Fady and Stuart to answer that question, please.

Yes. I'll let Stuart answer most of this. But remember, this is a Phase II study. The objectives are really to find the dose and to begin to get some sense of effectiveness. And Stuart, maybe you can take it from there.

Jason, thanks for the questions. First of all, we wouldn't expect that we would disclose the results of the first two cohorts independently of the results of the final study. So we'll look at the totality of the data and then disclose the results. The second question regarding effective doses, as Fady indicated, this is a dose-finding study in a population with a lot of comorbidities. This is an older population compared to the non-obstructive HCM patients we're studying in ACACIA. So we're taking a careful systematic approach, starting with lower doses and titrating up based on pharmacodynamic effects and safety and tolerability observed along the way. This systematic approach is designed to characterize the appropriate dose to take forward based on the benefit-risk profile.

And our next question will come from Serge Belanger from Needham & Co. Your line is open.

Hi, this is John for Serge. Thanks for taking my question. Just want to underscore the expectations now between both the US and EU with the amendment to ACACIA. Are regulators aligned on what would be considered approvable based on which, if not both endpoints, the trial needs to satisfy? Or is there any disparity on whether KCCQ or pVO2 are looked at in a different light between the two agencies?

I believe that as Fady can elaborate, we’ve harmonized feedback we received from regulatory agencies, but I’ll ask him to comment.

Yes. Again, when you don’t have a hard endpoint like mortality or hospitalization, regulators on both sides of the Atlantic are looking for consistency between patient function and perception of symptoms. It is unproductive to see someone improve in exercise capacity in peak VO2 if they do not perceive any benefit, and vice versa. So consistency between endpoints is essential, and both sides of the Atlantic agree on that. By designating certain endpoints and upsizing the trial, and harmonizing the primary endpoints, we were able to satisfy everybody, and ultimately, I think they'll have similar interpretations of the data at the end of the day.

Our next question comes from Yasmeen Rahimi from Piper Sandler. Your line is open.

Good afternoon, team. Thank you for the updates. What we need to understand is whether the issues surrounding the REMS are simply due to a procedural oversight where they should have requested a submission, but didn't, leading to your team not submitting because you were following their instructions. Or is there a deeper issue at play? It really boils down to this: is it just a procedural error that has now been rectified, or is there more to this situation, given that they are now requesting further information? I'm having difficulty grasping this aspect. I understand the sequence of events, and I found your comments very helpful. Please help clarify which scenario it is, as the stock performance suggests there may be more than just a procedural issue. It would be great if you could provide as much insight as possible.

I hear you struggling, and I’ll try to address this constructively. However, please understand there was no mishap. I recognize that this is causing some consternation amongst certain investors. We don’t believe at all that anything irregular occurred. This is part of a process where a sponsor communicates with the FDA and receives feedback. Based on that feedback, action is taken. FDA is within reason to make requests. There is nothing here to suggest anything new regarding risk and safety, but instead, we find that the management of risk is now structured through a REMS program instead of labeling. The differentiation we believed coming into the submission and throughout its review are consistent with the emerging clinical data. Ultimately, we believe the REMS program provides a structured management approach to risk while retaining our ability to position aficamten distinctively. I hope that helps separate the concerns.

Our next question comes from Ash Verma from UBS. Your line is open.

This is Natalie on for Ash. So I'm going to switch gears a little bit, and I actually have a question related to Edgewise. In particular, we want to understand how you view their recent clinical data. To get even more specific, we're really looking at the numbers here, and we were wondering if the ejection fraction measurements were done at peak like you've done in your program as opposed to doing them at trough, how much of a difference do you think that would have made to their measurements? And just do you have any other broad comments on that data that they put out? Thank you.

Yes. We did note the data that Edgewise presented, and it's not for us to make comparative statements about aficamten versus an investigational drug that’s in its early Phase II. Specifically, you asked about measurement of effect on EF. As you point out, we have been measuring EF changes in our studies when we believe the drug is having its more maximal effect and at Cmax exposures. I'll ask Fady to address what could be a delta between peak and trough. However, that is determined by each individual drug.

Yes. I think for aficamten, the change in ejection fraction on average is around 4%. What transpires between peak and trough is maybe one or two points. It’s hard to speculate since we didn’t make any measurements at those points in time. There are many factors that affect ejection fraction, including time of day and hydration. So it’s challenging to state exactly what the magnitude would be, other than it would be less. Similarly, I would expect if you measured a drug effect at peak for any drug, you might see a bit more of an effect. That goes for other measurements of efficacy as well.

And I am showing no further questions from our phone lines. I'd now like to turn the conference back over to Robert Blum for any concluding remarks.

I want to thank everybody for your participation in this call. I hope you've got clarification on the questions that you were pondering coming into this call. We addressed many topics, including a conversation about REMS. I hope you feel comfortable with our steps, and we are prepared given that we had a contingency plan that we executed. We remain confident in the potential approval of aficamten and upon its potential approval with a label and a REMS program that would provide distinct positioning for aficamten and enable us to execute on the commercial readiness program, albeit three months delayed. We are optimistic about how that will be received, and we are encouraged by the reception for candidates for our open commercial positions. We look forward to the upcoming data from MAPLE and are excited also about ACACIA, omecamtiv, and CK-586. So lots of exciting developments are unfolding within Cytokinetics. We look forward to providing new updates when appropriate. Thank you for your interest in this call. Operator, with that, we can now conclude.

Thank you. This concludes today's conference call. Thank you for participating. You may now disconnect.