Heart failure & cardiomyopathiesRandomised controlled trial
Effect of Mavacamten on Chinese Patients With Symptomatic Obstructive Hypertrophic Cardiomyopathy
- Randomised controlled trial
- phase 3
- double-blind
- placebo-controlled
- 2:1 randomisation
- 12 hospitals in China
Authors' conclusion
Mavacamten significantly improved Valsalva LVOT gradient vs placebo for Chinese patients. All secondary efficacy end points were also improved. Mavacamten was well tolerated with no new safety signals.
Study context
- Population
- Chinese patients with symptomatic obstructive hypertrophic cardiomyopathy, left ventricular outflow tract (LVOT) gradient ≥50 mm Hg and New York Heart Association (NYHA) class II or III
- Participants
- 81 patients
- Comparison
- Mavacamten vs placebo
- Mavacamtenn = 54
- Placebon = 27reference
- Primary endpoint
- Change in Valsalva LVOT peak gradient from baseline
- Follow-up
- Week 30
Primary result
As reported in the abstract
LSM difference
−70.3 mm Hg
95% CI −89.6 to −50.9
P < 0.001
Mavacamten vs Placebo
LSM difference −70.3 mm Hg (95% CI −89.6 to −50.9); P < 0.001
Secondary outcomes
Valsalva LVOT peak gradient <30 mm Hg · week 30
Valsalva LVOT peak gradient <50 mm Hg · week 30
NYHA class improvement · week 30
| Outcome | LSM difference (95% CI) | |
|---|---|---|
| KCCQ Clinical Summary Score, NT-proBNP, hs-cTnI, LVMI · KCCQ Clinical Summary Score | 10.2 (4.4–16.1) | |
| −1001020Difference (linear scale) |
| Outcome | Estimate |
|---|---|
| KCCQ Clinical Summary Score, NT-proBNP, hs-cTnI, LVMI · NT-proBNP | proportion of geometric mean ratio 0.18 (95% CI 0.13–0.24) |
| KCCQ Clinical Summary Score, NT-proBNP, hs-cTnI, LVMI · hs-cTnI | proportion of geometric mean ratio 0.34 (95% CI 0.27–0.42) |
| KCCQ Clinical Summary Score, NT-proBNP, hs-cTnI, LVMI · LVMI | mean difference −30.8 g/m² (95% CI −41.6 to −20.1 g/m²) |
- Valsalva LVOT peak gradient <30 mm Hg: 26 of 54 vs 1 of 27
- Valsalva LVOT peak gradient <50 mm Hg: 32 of 54 vs 2 of 27
- NYHA class improvement: 32 of 54 vs 4 of 27
Resting LVOT peak gradient · week 30
- Similar trends for resting LVOT peak gradient
- LSM difference −55.0 mm Hg (−69.1 to −40.9 mm Hg) (95% CI)
Safety
Safety and tolerability
- Similar between mavacamten and placebo
Left ventricular ejection fraction (LVEF) <50%
- No patients experienced LVEF <50%
Original publication
Effect of Mavacamten on Chinese Patients With Symptomatic Obstructive Hypertrophic Cardiomyopathy. JAMA Cardiol. Published 1 October 2023. doi:10.1001/jamacardio.2023.3030
Summarised from the published abstract; every number is checked against it