A trial published in Clinical Cancer Research demonstrated a positive response in both metastatic breast cancer and ovarian cancer to a recombinant poxviral vaccine.

Lead investigator James Gulley, M.D., Ph.D., director and deputy chief of the clinical trials group at the Laboratory of Tumor Immunology and Biology at the National Cancer Institute commented:

“With this vaccine, we can clearly generate immune responses that lead to clinical responses in some patients.”

For the trial, funded by the National Cancer Institute, Gulley and his team involved 26 patients, all of them heavily pretreated, with 21 patients receiving at least three prior chemotherapy treatments, and designated them to receive monthly vaccinations with PANVAC vaccine that contains transgenes for MUC-1, CEA and three T cell costimulatory molecules.

In 12 breast cancer patients the team established an average time to disease progression of 2.5 months and an average overall survival rate of 13.7 months. In four patients the disease was stable. The average time to progression for the 14 ovarian cancer patients was two months and the average survival rate of 15 months.

The most common side effect after treatment was mild reactions at the injection-site.

Because of the rising interest in cancer vaccinations, Gulley recommends for further studies to be conducted in order to establish which vaccines are beneficial for particular patients.

He concludes:

“The sustained benefit seen in some patients in this study underscores the potential for therapeutic vaccines to impact clinical outcomes without toxicity. However, more studies in the appropriate patient populations are required to adequately assess efficacy.”

Written by Petra Rattue