Ipilimumab (also called MDX-010, MDX-101, or BMS-734016) has been tested in multiple studies for many years and appears to finally be on the verge of FDA approval, perhaps as early as 2010. That's certainly good news for patients, who have few options once melanoma spreads to other areas of the body (stage IV disease).
How Does Ipilumumab Work?
Ipilumumab is an antibody that activates the body's immune system to fight melanoma by inhibiting the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) molecule. CTLA-4 is a molecule on T-cells, a type of white blood cell that plays a critical role in regulating natural immune responses. The presence of CTLA-4 suppresses the immune system's response to disease, so blocking its activity stimulates the immune system to fight the melanoma.
Three previous early-phase (phase II) clinical trials have shown that treatment with ipilimumab results in a one-year survival rate of 47% to 51% for people with stage III or IV melanoma, which is almost double the average.
It is being tested in advanced (phase III) trials by itself and in combination with vaccines, other immunotherapies (such as interleukin-2), and chemotherapies (such as dacarbazine). Overall response rates range from 13% with ipilimumab plus vaccine in patients with stage IV disease to 17% and 22% with ipilimumab plus dacarbazine or interleukin-2, respectively, in patients with metastatic disease. Responses have been long-lasting, and among those experiencing more severe side effects, even higher response rates have been seen (up to 36%). These results indicate that more than one-third of ipilimumab-treated patients with advanced melanoma experience a long-term survival benefit, a rare success story in the treatment of this disease.
Side EffectsUnlike chemotherapy, in which side effects become evident soon after beginning treatment, the side effects associated with ipilimumab can vary greatly, presumably because the human immune system varies from person to person.
The most common side effects of ipilimumab occur in the gastrointestinal tract (such as diarrhea and inflammation of the colon) and the skin (such as rash and inflammation of the skin). Less frequently occurring side effects include hepatitis, inflammation of the pituitary gland (hypophysitis), eye inflammation (uveitis), and kidney problems (nephritis). Side effects occur in up to 84% of patients but are generally mild and treatable.
The Clinical Trials
If you or a loved one has metastatic melanoma and are interested in learning about the current ongoing clinical trials for ipilimumab, visit ClinicalTrials.gov.
Hersh E, Weber J, Powderly J, et al (2009). Long-term survival of patients (pts) with advanced melanoma treated with ipilimumab with or without dacarbazine. J Clin Oncol 27:15s (suppl; abstr 9038).
Ledezma B (2009). Ipilimumab for advanced melanoma: A nursing perspective. Oncol Nurs Forum, 36(1), 97–104.
Sarnaik AA, Weber JS (2009). Recent advances using anti-CTLA-4 for the treatment of melanoma. Cancer J. 2009 May-Jun;15(3):169-73.