The US Food and Drug Administration (FDA) has granted accelerated approval to Celgene's Pomalyst (pomalidomide), a multiple myeloma drug chemically similar to thalidomide and lenalidomide, two drugs infamous for their side effects.
Multiple myeloma is a cancer of the plasma cells of the bone marrow. As the cancer cells accumulate, the body is less able to produce red blood cells or antibodies, resulting in anemia and infections. The disease varies in progression, occasionally taking years to develop, but is extremely deadly, killing more than 10,000 in the US each year. FDA estimates that 21,700 US patients are diagnosed with the disease each year.
Pomalyst works to inhibit the disease in patients who have failed to respond to both lenalidomide and bortezomib, and whose disease did not respond to treatment and progressed within 60 days of the last treatment.
The February 2013 approval of Pomalyst follows the July 2012 approval for Kyprolis (carfilzomib), another multiple myeloma treatment. Both drugs were approved under FDA's accelerated approval pathway, which reduces the amount of evidence necessary to obtain approval, shifting the generation of that evidence to the postmarket setting instead. Both drugs were also given orphan product designation due to the small number of multiple myeloma patients diagnosed each year in the US.
FDA's approval notice explained that the drug was found to be effective in a trial of 221 patients. Patients receiving Pomalyst alone achieved a 7.4% objective response rate (ORR), or a complete or partial disappearance of the cancer, while patients receiving Pomalyst combined with low-dose dexamethasone achieved a 29.2% ORR.
Because of the drug's similarity to thalidomide and lenalidomide, two drugs infamous for their effects on fetal development, the drug carries both a Boxed Warning and a Risk Evaluation and Mitigation Strategies (REMS) program. Both are designed to reduce embryo-fetal risk by establishing and communicating pregnancy testing and contraceptive requirements. The REMS is similar in nature to those for thalidomide and lenalidomide, FDA said.
According to the Boxed Warning, females should not become pregnant at any time while taking Pomalyst or four weeks before or after starting Pomalyst. While the drug has not been tested in pregnant women, it has been shown to cause harm to unborn animals during testing, the warning explained. Women are also advised not to breastfeed while taking the drug, as that can transmit Pomalyst.
As with similar drugs, Pomalyst can also be transmitted by men through sexual intercourse, and the warning explains that men "must use a latex or synthetic condom."
"If a female becomes pregnant with your sperm, the baby may be exposed to Pomalyst and may be born with birth defects," FDA explained.