Bristol announces new long-term follow-up data from Phase 3 Study of CAMZYOS

Bristol Myers announced new long-term follow-up results from the EXPLORER-LTE cohort of the MAVA-Long-Term Extension study evaluating CAMZYOS in adult patients with New York Heart Association class II-III symptomatic obstructive hypertrophic cardiomyopathy. The long-term follow-up efficacy and safety data, presented today at the European Society of Cardiology Congress in London, reinforce the established efficacy and safety profile of CAMZYOS, a first-in-class cardiac myosin inhibitor. With inclusion in both the ESC and AHA/ACC clinical guidelines as a recommended option for when symptoms persist after first-line therapy, CAMZYOS is a standard of care for symptomatic oHCM. Patients experienced consistent and sustained improvements in echocardiographic measures and biomarkers after up to 3.5 years of continuous treatment, including resting left ventricular outflow tract gradient, Valsalva LVOT gradient, left atrial volume index and N-terminal pro B-type natriuretic peptide levels. They also experienced an improvement in symptoms and functional capacity as measured by NYHA class and patient-reported outcomes, including most patients achieving NYHA class I. The safety profile of CAMZYOS for up to 3.5 years remained consistent with the established safety profile, with no new safety signals identified. Key findings from the EXPLORER-LTE data analysis showed sustained improvements from baseline to Weeks 156 and 180 in echocardiographic measures and biomarkers. In echocardiographic markers, patients experienced a reduction of 55.3 mmHg in Valsalva LVOT gradient at both Week 156 and 180 and a reduction of 40.2 mmHg and 40.3 mmHg in mean resting LVOT gradient at Week 156 and 180, respectively. Improvements from baseline to Weeks 144 and 180 were sustained in mean left atrial volume index, with patients experiencing a reduction of 3.5 mL/m2 and 5.5 mL/m2, respectively. The mean left ventricular ejection fraction decreased by 11% from baseline to Week 180, and the mean (63.9%) remained within normal range. Evaluation of biomarker data showed that median NT-proBNP levels decreased by 504 ng/L at Week 156 and 562 ng/L by Week 180. At Week 180, most patients were NYHA class I. Overall, 108 patients achieved a complete response – defined as achieving NYHA class I and a Valsalva LVOT gradient of less than or equal to30 mmHg during the study and retained a complete response until the data cutoff. Patient-reported outcomes as measured by the HCM Symptom Questionnaire found improvement in shortness of breath score from baseline with treatment during the first 12 weeks and was sustained through Weeks 156 and 180.