Melanoma is the deadliest form of skin cancer. When discovered early, it can usually be cured with surgery alone, but once it spreads (metastasizes) throughout the body, treatment options are limited. After decades of frustration for researchers, however, this promising new therapy is providing hope.
Yervoy (Ipilimumab) is a monoclonal antibody, an immune protein that binds to a molecule called CTLA-4 and inhibits it from functioning. CTLA-4 is a kind of brake on the immune system which keeps it from overfunctioning and thus attacking itself; by blocking it, ipilimumab kicks the immune system into higher gear so that it can identify, attack and eliminate melanoma cells.
In a large phase III trial of 676 advanced, inoperable melanoma patients published in 2010 in the New England Journal of Medicine, subjects previously treated unsuccessfully with other agents who received Yervoy or Yervoy plus a melanoma vaccine (gp100) lived on average 32 percent longer and had a 20 percent greater chance (45 percent vs. 25 percent) of surviving one year than those who received gp100 alone. And 24 percent were alive after two years, compared with just 14 percent of those treated with the other therapy. The impact of this trial cannot be overemphasized, as Yervoy was shown to be the first treatment ever to improve overall survival in advanced melanoma patients.
Now, in new study findings just announced, Yervoy was found to increase overall survival in inoperable stage III or stage IV metastatic melanoma patients who had not received prior therapy. The study specifically showed that ipilimumab combined with the chemotherapy dacarbazine increased overall survival, while dacarbazine alone did not. The findings will be submitted to the American Society of Clinical Oncology for potential presentation at its annual meeting in June.
Side effects of Yervoy are related primarily to the overactivation of the immune system, resulting in itching, skin rash and diarrhea. In fact, Yervoy may be more effective in patients who develop these side effects. However, in rare cases more dangerous side effects can occur, so patients are urged to enter studies with physicians well versed in managing its toxicities.
Another notable aspect of the treatment is that even in patients who ultimately see benefits, the disease may initially progress before it stabilizes or the tumor shrinks. For this reason, early clinical trials were at first deemed a failure before patients started to improve.
The medical community is enthusiastic about the approval of this new treatment. It represents a giant step towards the goal of curing this devastating disease.