Effective Triple Therapy for Metastatic Melanoma Based on Radiation and Dual Immunotherapy

Source: Radiation Therapy News, March 2015

A new study was recently published in the journal Nature showing an effective combination therapy for metastatic melanoma treatment along with the resistance mechanism underlying combined radiation therapy and ipilimumab in both patients and mice. The study is entitled “Radiation and dual checkpoint blockade activate non-redundant immune mechanisms in cancer.”

Melanoma is the most dangerous form of skin cancer and is caused by damage to skin cells (usually by ultraviolet radiation), triggering mutations that are not repaired and allowing skin cells to rapidly multiply and generate malignant tumors. Melanoma is curable when detected and treated early; if it goes undetected or if it recurs, the cancer can proliferate and spread (metastasize) to other parts of the body, becoming more difficult to treat.

The research team had previously concluded, based on a phase I clinical trial (“RadVax” trial), that the combination of radiation with ipilimumab (an antibody against CTLA4 [cytotoxic T-lymphocyte-associated protein 4], known to inhibit the immune system) was safe and capable of shrinking metastatic melanoma tumors in patients.

“These new immunotherapies are potent treatment options that have generated a lot of excitement in the past few years, but we know that many patients fail to respond, underscoring the need to further improve the drugs’ abilities,” said one of the study’s senior authors Dr. Andy Minn in a news release. “Anecdotally, we know that combining radiation with immunotherapy can be powerful, so we were very motivated to move forward with both a clinical trial to demonstrate that this combination is a promising route to pursue and with laboratory studies to understand why response happens and why it does not.”