FDA approves Vyndaqel and Vyndamax for use in patients with transthyretin amyloid cardiomyopathy

Pfizer Inc. announced that the FDA has approved both Vyndaqel (tafamidis meglumine) and Vyndamax (tafamidis) for the treatment of the cardiomyopathy of wild-type or hereditary transthyretin-mediated amyloidosis (ATTR-CM) in adults to reduce cardiovascular mortality and cardiovascular-related hospitalization. Vyndaqel and Vyndamax are two oral formulations of the first-in-class transthyretin stabilizer tafamidis, and the first and only medicines approved by the FDA to treat ATTR-CM.

Transthyretin amyloid cardiomyopathy is a rare, life-threatening disease characterized by the buildup of abnormal deposits of misfolded protein called amyloid in the heart and is defined by restrictive cardiomyopathy and progressive heart failure. Previously, there were no medicines approved to treat ATTR-CM; the only available options included symptom management, and, in rare cases, heart (or heart and liver) transplant. It is estimated that the prevalence of ATTR-CM is approximately 100,000 people in the U.S and only one to two percent of those patients are diagnosed today.

The recommended dosage is either Vyndaqel 80 mg orally once-daily, taken as four 20 mg capsules, or Vyndamax 61 mg orally once-daily, taken as a single capsule. Vyndamax was developed for patient convenience; Vyndaqel and Vyndamax are not substitutable on a per milligram basis.

The FDA approval was based on data from the pivotal Phase III Transthyretin Amyloidosis Cardiomyopathy Clinical Trial (ATTR-ACT), the first global, double-blind, randomized, placebo-controlled clinical study to investigate a pharmacological therapy for the treatment of this disease. In ATTR-ACT, Vyndaqel significantly reduced the hierarchical combination of all-cause mortality and frequency of cardiovascular-related hospitalizations compared to placebo over a 30-month period (p=0.0006). Additionally, individual components of the primary analysis demonstrated a relative reduction in the risk of all-cause mortality and frequency of cardiovascular-related hospitalization of 30% (p=0.026) and 32% (p<0.0001), respectively, with Vyndaqel versus placebo.

Comment: The condition it treats is often mistaken for heart disease, and Pfizer has acknowledged part of its task will be raising physician and patient awareness to increase diagnosis. The company believes as many as 100,000 people have the disease in the U.S.