The safety profile of CAMZYOS was evaluated in the Phase 3 EXPLORER-HCM and VALOR-HCM trials across a total of 219 patients with symptomatic obstructive HCM.1–3 The median treatment duration for patients receiving CAMZYOS was 30.1 weeks (range: 1.6–40.3 weeks).1
Most commonly reported adverse reactions with CAMZYOS1
5% (9/179) of patients in the CAMZYOS group experienced reversible reductions in
LVEF <50% (median 45%: range 35–49%) while on treatment1
- In 56% (5/9) of these patients, these reductions were observed without other clinical manifestations1
- In all patients treated with CAMZYOS, LVEF recovered following treatment interruption and they completed the study on CAMZYOS1
*Systolic dysfunction is defined as LVEF <50% with or without symptoms.1
Dyspnoea was reported in 12.3% (22/179) of patients treated with CAMZYOS vs 8.7% (16/184) of patients on placebo1
- In the EXPLORER-HCM study, 67% of dyspnoea events were reported after CAMZYOS was discontinued, with median time to onset of 2 weeks (range: 0.1–4.9) after last dose1
CAMZYOS was generally well tolerated in the Phase 3 EXPLORER-HCM trial, with few patients discontinuing their treatment1,2
(244/251) completion rate in the EXPLORER-HCM trial across both treatment groups at Week 302
Most common serious adverse events in EXPLORER-HCM with CAMZYOS2
Rates of treatment discontinuation in the EXPLORER-HCM trial were low with CAMZYOS (2%;n=3/123) and comparable to placebo (2%;n=2/128)2
CAMZYOS was generally well tolerated with few patients discontinuing their treatment in the VALOR-HCM trial at Week 563,4
(96/108) completion rate in the VALOR-HCM trial at Week 563
Atrial fibrillation was the most common serious adverse event in VALOR-HCM with CAMZYOS [3% (3/108)]4
Rate of treatment discontinuation in the VALOR-HCM trial at Week 56 was low with CAMZYOS (4%;n=2/52)*3,4
*All patients who discontinued treatment were in the original placebo group. 2 of 52 (3.8%) discontinued treatment due to LVEF <30% and 1 of 52 (1.9%) discontinued treatment due to two consecutive LVEF measurements <50% despite dose reduction of CAMZYOS to 2.5 mg daily.3,4
CAMZYOS was generally well tolerated and had no new safety signals in the EXPLORER-LTE study5
The long-term safety profile of CAMZYOS was evaluated in the EXPLORER-LTE trial in 231 patients with obstructive HCM (data cutoff 31 August 2023). The median treatment duration for patients receiving CAMZYOS was 166.1 weeks (range: 6.0–228.1 weeks); 99 (42.9%) of patients had completed the Week 180 visit.5
Summary of TEAEs and serious TEAEs through to Week 180*5
*TEAEs were recorded and defined based on the discretion of the principal investigator.5
†Defined as serious TEAEs related to major adverse cardiovascular events, atrial fibrillation, ventricular arrhythmias, syncope/pre-syncope, cardiac failure, hypotension, and QTcF prolongation.5
‡Includes cardiac failure (n=3), decreased ejection fraction (n=5), atrial fibrillation (n=1), and atrial flutter (n=1).5
§Number of events that occurred while patients were receiving treatment at the time of the event.5
**Owing to bacterial endocarditis (n=1), cardiac arrest (n=1), acute myocardial infarction (n=1; sudden death without an autopsy performed), intracerebral haemorrhage due to arteriovenous malformation (n=1), and progression of liver metastases with cholangitis and new onset biliary dilation (n=1); all unrelated to CAMZYOS. Of the 5 patients who died, 1 did not experience an individual TEAE considered to be of fatal severity.5
Rate of CAMZYOS discontinuation in the EXPLORER-LTE trial was low (6%;n=13/231)5
Drug-related serious TEAEs with CAMZYOS in EXPLORER-LTE were low, occuring in 4% (n=10/231) of patients; of these, 60% of patients remained on CAMZYOS at the data cutoff date5
Atrial fibrillation occurred in 14% (33/231) of patients; of these, 46% had a medical history of atrial fibrillation5
See CAMZYOS dosing
Please refer to the CAMZYOS Summary of Product Characteristics for further information on dosing, initiation and safety.
CV, cardiovascular; HCM, hypertrophic cardimyopathy; LTE, long-term extension; LVEF, left ventricular ejection fraction; QTcF, QT interval corrected using Fridericia's formula; TEAE, treatment-emergent adverse event.
References
- CAMZYOS (mavacamten) Summary of Product Characteristics.
- Olivotto I et al. Lancet. 2020;396(10253):759–769.
- Desai MY et al. JAMA Cardiol. 2023;8(10):968–977.
- Desai MY et al. JAMA Cardiol. 2023;8(10):968–977 (supplementary appendix).
- Garcia-Pavia P et al. Eur Heart J. 2024. ehae579.