FDA approves new treatments for transthyretin-mediated amyloidosis-cardiomyopathy
The U.S. Food and Drug Administration approved tafamidis meglumine and tafamidis capsules for the treatment of cardiomyopathy caused by transthyretin-mediated amyloidosis (ATTR-CM) in adults. These are the first FDA-approved treatments for ATTR-CM. The agents have the same active moiety, tafamidis, but they are not substitutable on a milligram to milligram basis and their recommended doses differ.
ATTR is caused by the build-up of abnormal deposits of amyloid protein in organs and tissues, interfering with their normal functioning. These protein deposits most frequently occur in the heart and the peripheral nervous system. Heart involvement can result in shortness of breath, fatigue, heart failure, loss of consciousness, abnormal heart rhythms and death. Involvement of the peripheral nervous system can result in a loss of sensation, pain, or immobility in the arms, legs, hands and feet. Amyloid deposits can also affect the kidneys, eyes, gastrointestinal tract and central nervous system.
The efficacy of tafamidis meglumine and tafamidis capsules in treating ATTR-CM was shown in a clinical trial of 441 patients randomized to receive tafamidis meglumine or a placebo. After an average of 30 months, the survival rate was higher in the tafamidis meglumine group than in the placebo group. Tafamidis meglumine was also shown to reduce the number of hospitalizations for cardiovascular problems.
The number of patients in clinical studies was small, but no drug-associated side effects have been identified. Tafamidis may cause fetal harm when administered to a pregnant woman. Women taking tafamidis meglumine and tafamidis capsules should discuss pregnancy planning and prevention with their health care professional.
The FDA granted tafamidis meglumine Fast Track, Priority Review and Breakthrough Therapy designations. Tafamidis meglumine and tafamidis capsules each received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases.