Protox announces positive clinical data from prostate cancer study

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Protox Therapeutics Inc. announces positive top-line results from its Phase I clinical trial evaluating PRX302 in patients with localized, recurrent prostate cancer following radiation failure. The trial results indicate that PRX302 is safe and well tolerated and shows promising signs of therapeutic activity following a single intra-prostatic treatment.

"The completion of the PRX302 Phase I trial is encouraging from two perspectives," said Dr. Scott Coffield, principal investigator from the lead site, Scott and White Memorial Hospital. "First, there was therapeutic benefit demonstrated through overall PSA reduction in study patients, as well as a reduction in the number of positive biopsies after treatment. Second, there was no significant adverse side effect profile at the highest dose of PRX302 given to patients in this trial."

"It is heartening to see promising results at this stage of the clinical development program in a patient population which has limited therapeutic options," said Dr. Fahar Merchant, president and chief executive officer of Protox. "These data support our heightened confidence regarding the potential of PRX302 for the treatment of not only prostate cancer, but also BPH, which is currently being evaluated in an ongoing Phase I trial."

This study is intended to examine the safety, tolerability and therapeutic activity of PRX302 in patients with localized recurrent prostate cancer who show signs of disease progression as evidenced by rising levels of PSA (prostate specific antigen) following radiation treatment. Using a well-established, image-guided technique, PRX302 was administered directly into the prostate. A total of 24 patients were treated in this trial. Protox has concluded that despite a 100-fold escalation in dose, the maximum tolerated dose (MTD) was not reached in this study while encouraging signs of therapeutic activity were observed.