In a recent study, researchers at the Dana-Farber Cancer Institute found that giving patients with advanced melanoma or ovarian cancer that have been immunized with a GVAX vaccine, periodic infusions of anti-CTLA-4 antibodies provides a strong immune response to tumors with less-severe side effects.
The study to be published online by the Proceedings of the National Academy of Sciences, involved a cancer vaccine made from patients’ own tumor cells. The vaccine is created by removing tumor cells from the body, irradiating them so they stop growing, and inserting a gene that causes them to produce a protein called GVAX. When the cells are then re-infused into patients, GVAX acts like a siren to the immune system, prompting a more energetic attack on cancer cells throughout the body. Unfortunately, these results rarely last and patients treated with the vaccine usually die as their disease continues to progress. So the researchers took it one step further and began studying whether combining GVAX vaccines with monoclonal antibody therapy could lengthen remissions, since blocking CTLA-4 could bolster the immune response spurred by the vaccine.
To test this theory, 11 melanoma patients were infused with a CTLA-4-blocking antibody (Ipilumimab (R)) one to four months after receiving GVAX, and every two to three months as needed. None of the patients had severe side effects, although they all developed mild, low-level inflammatory conditions (usually a rash that went away in a few days). Moreover, in eight of the participants, tumors throughout the body either receded or became stable. The three other patients experienced less dramatic improvements that became apparent after several months of therapy.
Nine patients with advanced ovarian cancer were also given the same treatment. Two of them did develop severe inflammatory problems. Although large die-offs of tumor tissue were less common than in the melanoma group, some of the ovarian cancer patients did experience similar results.

Source: Dana-Farber Cancer Institute