FDA Approves 2 New Melanoma DrugsMay 30, 2013
The US Food and Drug Administration (FDA) has approved 2 new drugs, Tafinlar (dabrafenib) and Mekinist (trametinib), to treat melanoma that has spread (metastasized) or that can’t be surgically removed. Melanoma is not as common as some other types of skin cancer, but it can be more dangerous.
Both of the new drugs are intended to treat patients whose cancers have certain changes (mutations) in the BRAF gene. Melanoma can be caused by changes to certain genes that help the cells grow and divide. About half of melanoma tumors have changes in the BRAF gene. The FDA also approved a test to determine whether a melanoma has the kind of gene mutation that can be treated by the new drugs.
Approval of the drugs and the test were based on results of clinical trials.
Tafinlar was studied in 250 people with BRAF-mutated melanoma that had metastasized or was inoperable. They were randomly assigned to receive Tafinlar or a chemotherapy drug. It took an average 2.4 months longer for the cancer to get worse in those who received Tafinlar compared to those who received the chemotherapy drug.
Mekinist was studied in 322 people who had melanoma with a BRAF mutation and that had metastasized or was inoperable. They were randomly assigned to receive Mekinist or a chemotherapy drug. It took an average 3.3 months longer for the cancer to get worse in those who received Mekinist compared to those who received the chemotherapy drug.
Both drugs have several possible side effects.
The most common side effects from Tafinlar included thickening of the skin, non-cancerous skin tumors, headache, fever, joint pain, hair loss, and hand-foot syndrome. Less common, but more serious side effects included an increased risk of another type of skin cancer (squamous cell carcinoma); fever complicated by low blood pressure, shaking chills, dehydration, and kidney failure; eye problems; and increased blood sugar levels.
The most common side effects from Mekinist included rash, diarrhea, swelling, and acne-like skin breakouts. Less common, but more serious side effects included heart failure, lung inflammation, skin infections, and loss of vision.
Both drugs can cause infertility, and if taken by pregnant women, could harm the fetus. Both drugs are marketed by GlaxoSmithKline. The genetic test is made by bioMerieux.
Reviewed by: Members of the ACS Medical Content Staff