Carfilzomib Approved for Advanced Multiple Myeloma
Carfilzomib Approved for Advanced Multiple MyelomaThe Food and Drug Administration (FDA) has approved carfilzomib (Kyprolis) to treat patients with multiple myeloma whose disease has progressed after at least two prior therapies, including bortezomib (Velcade) and an agent that modulates the immune system such as thalidomide.
Carfilzomib binds to and inhibits enzymes called proteasomes, which degrade cellular proteins. Inhibiting this process leads to cell death and blocks tumor growth.
The July 20 approval was based on the response rate observed in a single-arm study of 266 patients with multiple myeloma who had received at least two prior therapies. One patient taking carfilzomib had all signs of cancer disappear (complete response) and 60 others saw their tumors shrink (partial response), resulting in an overall response rate of 22.9 percent. The median length of time patients responded to carfilzomib was 7.8 months.
Common side effects (observed in more than 30 percent of patients) included fatigue, nausea, anemia, lower-than-normal numbers of red blood cells or platelets, shortness of breath, diarrhea, and fever. Serious adverse reactions were reported in 45 percent of patients. The most common of these were pneumonia, acute kidney failure, fever, and congestive heart failure. The risk of peripheral neuropathy is less with carfilzomib than with similar drugs already on the market, such as bortezomib.
Carfilzomib was approved through the FDA’s accelerated approval program, which allows the agency to approve a drug based on clinical data demonstrating a drug’s effect on a surrogate endpoint, such as response rate, that is likely to predict its benefit to patients. The manufacturer, Onyx Pharmaceuticals, must submit additional data that confirm the drug’s clinical benefit.