New cancer vaccine being called a medical breakthrough

In what is being called a medical breakthrough, a vaccine that targets skin cancer has shown improved response rates and progression-free survival for patients when combined with the immunotherapy drug, Interleukin-2.

This new research was released today at the American Society of Clinical Oncology meeting in Orlando, Florida.  The breakthrough comes after three decades of failed attempts to produce cancer vaccines. The vaccine, developed by the National Cancer Institute (NCI) and called gp 100:209-217, or gp 100, helped shrink tumors as well as delay worsening of the disease in the study.

Vaccines work by training the body’s immune system to distinguish diseased cells and attack them. The hypothesis is that once the body can distinguish cancer cells, it can kill them before cancer has a opportunity to recur in a patient.

“Obviously, this is a disease, in its advanced setting, in need of better therapies for our patients,” said Hwu, a co-investigator on the study.

“While more follow up is needed, this study serves as a proof-of-principle for vaccines’ role in melanoma and in cancer therapy overall. If we can use the body’s own defense system to attack tumor cells, we provide a mechanism for ridding the body of cancer without destroying healthy tissue,” the expert added.

Approximately 22 percent of patients given the vaccine plus interleukin-2 saw their tumors shrink by half or more, compared with 10 percent of people getting interleukin-2 alone. Vaccine users saw their cancer stabilize for three months versus half that time for the others.

Melanoma is the most dangerous type of skin cancer. The five year-survival rates for local and metastatic melanoma are 65 percent and 16 percent, respectively. In 2009, an approximated 69,000 people in the U.S. will be diagnosed with melanoma and about 8,600 will die of the disease, according to the American Cancer Society.