Scientists have been trying to find a cure for advanced prostate cancer or at least a solution for delaying the disease's effects. So, they have created a vaccine that seems to improve the immune response to fight prostate cancer. The vaccine is still under clinical trials to test its complete efficiency, to adjust doses and to see if it works on less advanced prostate cancer.

Eric J. Small, MD, UCSF professor of medicine and urology, along with other 19 US institutions conducted the study which was funded by the Dendreon Corporation (the developer of the vaccine) based in Seattle, Washington. They tested 31 patients who were suffering of asymptomatic metastatic hormone refractory prostate cancer (HRPC) and had only one year left to live. The study was designed for observing if the disease progression will be delayed and patients will survive longer. In July1, 2006 the Journal of Clinical Oncology published the first conclusions of this research.

After two months of treatment with Provenge, 20 of the patients developed a responsive immunity against a protein situated on the surface of prostate cells (prostatic acid phosphatase). In these patients, the disease progressed after 34 weeks, but in the case of the other 11 patients the disease progressed after 13 weeks.

The vaccine was well tolerated by patients and the side effects were mild: fever and chills. Five of the subjects declared they had mild urinary problems. This is good news because chemotherapy gives a lot of unbearable side effects.

The vaccine has been made out of a genetically engineered protein and a dendritic cell provided from the patient's bloodstream.

T.J. Koerner, PhD, scientific program director for the American Cancer Society (ACS)said that the vaccine needs to be still under trials because doses need to be adjusted and drug combination must be tried. Also, the scientists want to see if this vaccine will work on less advanced prostate cancer. Until now the researchers do not know what the consequences of a long term treatment with this vaccine are upon the patients.

In US, prostate cancer is quite common and more than 200,000 new cases are discovered every year. Most of the patients can follow a treatment based on surgery, radiation and hormone therapy, but asymptomatic metastatic HRPC is known to be resistant to hormone therapy and every year more than 30,000 men die because and no other treatment is effective against the disease, this is why a treatment is urgently required.