Vemurafenib (Zelboraf) is a medication to treat advanced melanoma. It works by turning off a “switch” that tells cells to divide in patients with the BRAF gene which accounts for about one-half of all cases of melanoma. Although vemurafenib is an effective treatment, most people develop a resistance to the medication within six months and experience a relapse of skin cancer. A new study might provide a way to stop the return of the disease.
Advanced melanoma, or Stage IV cancer, is when the cancer has spread from the original site to other areas of the body. While the cancer can spread to any part of the body, it most commonly spreads to the lungs, liver, bones, brain, abdomen or lymph nodes.
Vermurafenib, which was approved for the treatment of skin cancer by the U.S. Food and Drug Administration (FDA) in August 2011. According to a study published in the New England Journal of Medicine in June, 2011, this medication improved survival rates of people with advanced melanoma compared to other medications.
When prescribed vemurafenib, you usually continue to take it until it stops working, unless you cannot tolerate the side effects, which might be severe. The side effects include sensitivity to sunlight, rashes, developing squamous cell carcinoma, loss of appetite, fatigue, hair thinning, diarrhea or constipation and aches and pains. Because everyone reacts to medication differently, it is impossible to say whether someone will experience severe side effects. Some people experience very mild side effects which do not interfere with treatment.
The study, completed at the Cancer Research UK Manchester Institute and published in Nature Communications, found that certain enzymes in the cells cause the reactivation of skin cancer by turning the switch back on and allowing cells to quickly divide again, despite treatment. These enzymes are found in those that have the BRAF gene as well as some that do not. By blocking these enzymes, the researchers hope vemurafenib will continue to work.
What the Study Means
Although vemurafenib has been found to be effective, the length of treatment is limited by how long the medication continues to work until the body finds a way around the treatment, in other words, your body adapts to the medication and the cancer cells start dividing again. The researchers were excited about the results because there are experimental drugs that are able to block the enzymes responsible for stopping vemurafenib from working and reactivating the cancer. By discovering which enzymes are responsible, the researchers can test the experimental drugs to determine if they can help to stop the enzymes from opening new pathways for the cancer to spread.