Cytokinetics, Incorporated (Nasdaq: CYTK) announced that Health Canada has issued a Notice of Compliance authorizing MYQORZO (aficamten) for the treatment of symptomatic obstructive hypertrophic cardiomyopathy (oHCM) in adults with New York Heart Association class II-III disease.

The Canadian authorization is the fifth regulatory approval for MYQORZO in less than a year, according to the company. The drug was previously approved by the U.S. Food and Drug Administration in December 2025, followed by China's National Medical Products Administration, the European Commission, and the UK's Medicines and Healthcare products Regulatory Agency earlier in 2026.

MYQORZO is a once-daily oral cardiac myosin inhibitor that reduces cardiac contractility and left ventricular outflow tract obstruction in oHCM patients.

The Health Canada decision is supported by results from the Phase 3 SEQUOIA-HCM trial, published in the New England Journal of Medicine. The trial showed that 24 weeks of aficamten treatment increased peak oxygen uptake by 1.76 mL/kg/min from baseline, compared to 0.0 mL/kg/min in the placebo group, representing a least squares mean difference of 1.74 mL/kg/min (p=0.000002).

In the trial, treatment-emergent serious adverse events occurred in 5.6% of patients on MYQORZO versus 9.3% on placebo. Left ventricular ejection fraction below 50% was observed in 5 patients (3.5%) on MYQORZO compared to 1 patient (0.7%) on placebo. Hypertension was the only adverse reaction occurring in more than 5% of patients and more frequently on MYQORZO than placebo (8% vs. 2%).

Canada's Product Monograph for MYQORZO includes a boxed warning for the risk of heart failure, noting the drug reduces left ventricular ejection fraction and can cause heart failure due to systolic dysfunction. Initiation is not recommended in patients with ejection fraction below 55%.

Cytokinetics said it plans to submit a Supplemental New Drug Application for aficamten in non-obstructive HCM in the fourth quarter of 2026, following positive topline results from the ACACIA-HCM Phase 3 trial.