There are several ways to combat deadly melanoma. One way is to attack the cancer by bolstering the body’s immune system to fight the disease. Another way is to block a genetic mutation known as BRAF, which may help the disease grow. This week it was announced that two giants, Bristol Meyers Squibb and Roche will combine forces to find a best practice solution.
Bristol’s Yervoy, the immune system enhancer, and Roche’s vemurafenib, the BRAF blocker, have both shown their independent effectiveness in treating the deadly form of skin cancer, and new data on them will be highlighted at this weekend’s annual meeting of the American Society of Clinical Oncology. However a big barrier is that Yervoy is administered intravenously, while vemurafenib is taken as a pill.
Yervoy was approved by the Food and Drug Administration in March, becoming the first drug approved for advanced melanoma in more than a decade. Roche’s vemurafenib was recently submitted for approval in the United States and Europe.
Roche estimates that about half of all melanoma patients have the BRAF mutation. Mutations in the BRAF gene can cause disease in two ways. First, mutations can be inherited and cause birth defects. Second, mutations can appear later in life and cause cancer, as an oncogene.
Inherited mutations in this gene cause cardiofaciocutaneous syndrome, a disease characterized by heart defects, mental retardation and a distinctive facial appearance. Acquired mutations in this gene have also been found in cancers, including non-Hodgkin lymphoma, colorectal cancer, malignant melanoma, papillary thyroid carcinoma, non-small cell lung carcinoma, and adenocarcinoma of the lung.
Yervoy on the other hand is the first drug ever shown to help late-stage melanoma patients live longer. However, it does not cure the disease. Yervoy is a biologic therapy; a man-made antibody that blocks a crucial switch on immune cells called CTLA-4. Cancers use this switch to turn off the body’s anticancer immune responses.
Most drugs like this come with possibly severe side effects, and Yervoy is no exception. The drug can provoke powerful autoimmune reactions in which the immune system attacks normal cells in the body. In clinical trials, nearly 13% of patients taking Yervoy had severe or fatal autoimmune reactions.
The companies will conduct an exploratory Phase I/II study to gauge the safety and effectiveness of the combination in patients that have the mutation. Depending on the findings, they may further develop the combination.
Melanoma is the most serious form of skin cancer. If it is recognized and treated early, it is almost always curable, but if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can be fatal. While it is not the most common of the skin cancers, it causes the most deaths.
The American Cancer Society estimates that at present, about 120,000 new cases of melanoma in the US are diagnosed in a year. In 2010, about 68,130 of these were invasive melanomas, with about 38,870 in males and 29,260 in women.
Sources: New England Journal of Medicine, British Medical Journal and
Written By Sy Kraft