ACC: Cytokinetics’ Four MYQORZO (aficamten) Presentations

In a March 2026 announcement, Cytokinetics said it will deliver four ACC 2026 presentations focused on MYQORZO (aficamten) in symptomatic obstructive hypertrophic cardiomyopathy. The presentations draw on SEQUOIA‑HCM, MAPLE‑HCM, and FOREST‑HCM. The release previews a pooled, comparative efficacy analysis; an evaluation of temporary treatment interruption (“washout”) with subsequent reinitiation and reported safety observations; a hypertension subgroup analysis describing blood-pressure changes and emergent uncontrolled-hypertension rates; and an analysis relating ECG findings to echocardiographic changes. It also reiterates regulatory and program details tied to labeling and distribution requirements as part of the broader ACC update.

For comparative efficacy, the company describes a pooled analysis combining SEQUOIA‑HCM and MAPLE‑HCM in which patients were grouped to evaluate aficamten monotherapy, metoprolol monotherapy, or placebo without background beta‑blockers (n=371). Beta‑blocker monotherapy was reported as no different from placebo across outcome categories listed as including exercise capacity, symptoms, cardiac biomarkers, and Valsalva gradient. The release also reports that aficamten monotherapy was superior to both metoprolol and placebo in this pooled comparison, consistent with previously published findings referenced in the announcement. Cytokinetics presents this pooled comparison as the main efficacy signal highlighted in the ACC materials it is describing.

On treatment interruption and reinitiation, the release summarizes an analysis drawing on SEQUOIA‑HCM and FOREST‑HCM that included 182 participants and evaluated discontinuation of aficamten for a four‑week washout after the primary endpoint assessment at 24 weeks per the SEQUOIA‑HCM protocol. According to the company’s description, washout was not associated with an increased risk of cardiac adverse events or rebound compared with placebo during interruption.

The release adds that most patients subsequently reinitiated therapy in the open‑label extension and that the analysis reported a favorable therapeutic response after reinitiation; it also notes that a small number of patients experienced recurrence of moderate HCM symptoms after discontinuing aficamten.

The release also highlights a MAPLE‑HCM subgroup analysis focused on comorbidity, describing results among 175 patients, half of whom had a history of hypertension. In the company’s summary, mean blood pressure changed by +3.6±14.0 mmHg with aficamten versus −8.3±18.2 mmHg with metoprolol. The release also reports emergent uncontrolled hypertension during treatment in 34% versus 25% of patients in the aficamten and metoprolol arms, respectively (p=0.38). Cytokinetics frames these subgroup data as a focused look at blood‑pressure effects within the MAPLE‑HCM dataset.

In an ECG-focused SEQUOIA‑HCM analysis, the release reports that aficamten compared with placebo was associated with lower odds of ST segment changes (adjusted OR 0.23; 95% CI 0.11–0.46; p<0.001) and LVH strain pattern (adjusted OR 0.15; 95% CI 0.06–0.41; p<0.001) after 24 weeks, and it notes that the effect on LVOT gradient was described as similar regardless of baseline LVH strain pattern. Cytokinetics describes aficamten as an allosteric, reversible cardiac myosin inhibitor and states that it is approved in the U.S., EU, and China. The release also summarizes restricted-program elements under a REMS.