Prostate cancer growth is influenced by the male hormone testosterone. Treatment with drugs that stop the production of testosterone often results in a decrease of the tumor or inhibition of its growth. This is particularly important prior to radiotherapy, since radiation can better be focused on the prostate with as a result less frequent or less severe side effects of the radiation.
Most of the drugs used to date to stop the production of testosterone have the disadvantage that initially they may cause a rise of testosterone levels before the production is effectively blocked. The new drug that will be investigated in this trial is a vaccine. The vaccine offers a different treatment modality since it interferes at a different level of the hormonal axis that drives the testosterone production; it will not cause an initial surge.
In this trial the vaccine will be administered three times, testosterone levels will be monitored for a total period of three months.
