FDA OKs First Agents for ATTR Cardiomyopathy

Physicians treating transthyretin amyloid (ATTR) cardiomyopathy will now have access to the first FDA-approved agents on the market for this rare disease.

The FDA simultaneously approved tafamidis meglumine (Vyndaqel) and tafamidis (Vyndamax) on Friday for the treatment of wild-type or hereditary ATTR cardiomyopathy, in which amyloid builds up in the heart and is associated with progressive heart failure. The now-approved oral transthyretin stabilizers work by slowing the formation of amyloid.

Approval was based on ATTR-ACT, a phase III trial of 441 patients that showed a significant reduction in mortalities and cardiovascular hospitalizations among those randomized to tafamidis. The 30-month mortality rate was 29.5% in the tafamidis-treated group compared with 42.9% in the placebo group (HR 0.70, 95% CI 0.51-0.96), and the rate of cardiovascular-related hospitalizations during the trial was 0.48 per year with tafamidis versus 0.70 per year with placebo (relative risk ratio 0.68, 95% CI 0.56-0.81). The tafamidis group showed no increase in adverse events, but animal studies have suggested that the drug may cause fetal harm when used by pregnant women.

Recommended dosages are 61 mg once-daily (single capsule) for Vyndamax and 80 mg once-daily (four capsules) for Vyndaqel, which will have a list price of $225,000 a year, Reuters reported. The two drugs are not substitutable on a per mg basis.

Tafamidis was rejected by the FDA in 2012 for treatment of familial ATTR polyneuropathy, but the drug is approved for this indication in 40 countries outside the U.S., including in Europe and Japan.

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