Stuart Kupfer
Analyst · Oppenheimer
Thanks, Fady. During the quarter, we were pleased to announce that the FDA granted breakthrough therapy designation for aficamten for the treatment of symptomatic obstructive HCM based largely on the data generated from the Phase II clinical trial, Redwood-HCM. HCM remains an area of high unmet need with few treatment options for patients who often experience many symptoms that impact their daily quality of life. A few weeks ago, we also shared top line results from Cohort 3 of Redwood HCM conducted in patients with obstructive HCM who were refractory despite treatment with the last line of medical therapy disopyramide. Results showed that substantial reductions were achieved in the average resting and post-Valsalva left ventricular outflow tract gradients. These decreases were achieved with only modest decreases in average LV ejection fraction with no patients whose ejection fraction fell below the prespecified safety threshold of 50%. The pharmacokinetics and safety and tolerability profile of aficamten were consistent with prior experience in Redwood-HCM, and there were no treatment interruptions. We look forward to presenting the full results of Cohort 3 at the ACC Annual Scientific Session in April. Yesterday, we were pleased to announce the opening of enrollment in Sequoia-HCM, the Phase III registrational trial of aficamten. Sequoia-HCM is a randomized, double-blind, placebo-controlled international clinical trial designed to compare 24 weeks of treatment with aficamten or placebo in patients with symptomatic obstructive HCM, who has substantial outflow track gradient despite background medical therapy. The primary objective is to evaluate the change from baseline to week 24 in peak VO2, measured by CPET as a measure of exercise capacity. We expect to enroll 270 patients to aficamten or placebo in addition to standard of care, randomized in a 1:1 ratio. Following the positive results of Cohort 3 of Redwood-HCM, patients whose background therapy includes disopyramide will also be eligible to enroll. Each patient will receive up to 4 escalating doses of aficamten or matching placebo, beginning with 5 milligrams once daily and escalate the 10, 15 or 20 milligrams once daily as needed to achieve target outflow track gradients. Dose escalation is based on echocardiography alone. Secondary objectives include evaluations of the change in KCCQ clinical symptom score and New York Heart Association Functional Class at week 12 and week 24. While the inclusion and exclusion criteria are summarized in yesterday's press release, one of the key criteria I want to call out is that we'll be enrolling patients with peak V02 less than 80% of that predicted for each patient, indicating a clear and objective reduction in exercise performance. Therefore, we do expect to enroll a patient population whose decreased functional capacity is characterized by an objective rigorous measurement. We anticipate enrollment of Sequoia-HCM to take roughly 1 year and therefore, expect to enroll through the duration of this year. Meanwhile, we're continuing to enroll prior patients from Redwood-HCM into the open-label extension study, Redwood-HCM OLE. A great majority of patients from Redwood HCM are choosing to continue into the open-label extension with 37% -- with 37 patients so far included at sites that are open to enrollment. We look forward to sharing the first data cut from the open-label extension of Redwood HCM later this year. This year, we also plan to expand the development program for aficamten. First, we plan to add a cohort 4 to Redwood-HCM to enroll symptomatic patients with nonobstructive HCM. This approach will enable us to move more expeditiously into a potential pivotal clinical trial in nonobstructive HCM thereafter. We expect to begin enrolling cohort 4 at several sites starting in the United States very soon. It will include approximately 30 to 40 patients with nonobstructive HCM enrolled in an open-label fashion to escalating doses of aficamten of 5, 10 or 15 milligrams as informed by echocardiography. The primary objective will be safety and tolerability of aficamten in this patient population, but we'll also evaluate their biomarker and symptom responses. Further details of the design of Cohort 4 will be provided when we announce that, that is open to enrollment. Second, later in 2022, we plan to start an additional Phase III clinical trial of aficamten in obstructive HCM to better understand its use relative to current standard of care therapy. The results from this trial may be incorporated into treatment guidelines or an expansion of the label of aficamten, following its potential initial approval that may be based on the results of SEQUOIA-HCM. Our planning to conduct a second Phase III clinical trial of aficamten is further testament to our confidence in the next-in-class profile of aficamten. We look forward to sharing more details about the expansion of this important development program for aficamten throughout the year. Turning now to reldesemtiv. We continued enrolling patients in COURAGE-ALS, the Phase III clinical trial of reldesemtiv in ALS. As a reminder, this is a large international trial that will enroll 555 patients with ALS in US, Canada, Australia, and Europe. And it builds on the results from FORTITUDE-ALS, the Phase II clinical trial, which showed that patients on all dose groups of reldesemtiv experienced less disease progression than patients on placebo with larger and clinically meaningful differences emerging over time. During the past quarter, we presented data from our ALS program at the International Symposium on ALS/MND. Among the presentations was an analysis of the baseline characteristics of the first 27 patients enrolled in COURAGE-ALS, which showed that the majority of patients enrolled at the timing of the analysis for middle progressors or fast progressors as was intended by the inclusion criteria of COURAGE-ALS to increase the sensitivity of detecting a treatment effect. As we continue to enroll the potentially pivotal clinical trial this year, we expect the data monitoring committee to conduct the first interim analysis in the trial, which will assess for futility and has triggered 12 weeks after approximately 1/3 or more of the planned number of patients is randomized. We remain enthusiastic about what COURAGE-ALS may deliver for patients with ALS. These patients and their advocacy organizations are fighting tirelessly to support the development of new therapies for what is truly a terrible disease. These patients continue to inspire us every day. With that, I'll turn the call over to Andrew.