Protox announces positive Phase 2b BPH results

13-Jan-2010 - Canada

Protox Therapeutics Inc. announced positive top-line results from its double-blinded placebo controlled Phase 2b study of PRX302 (study name: TRIUMPH) in patients with moderate to severe benign prostatic hyperplasia (BPH). The study achieved its primary clinical endpoint of a statistically significant improvement in International Prostate Symptom Score (IPSS) for patients treated with PRX302 versus subjects receiving placebo (p=0.0238, ANCOVA).

TRIUMPH was a double-blinded, placebo-controlled, multi-centre Phase 2b study in subjects with moderate to severe BPH. Enrolment criteria included baseline IPSS scores greater than or equal to 15, a maximum urinary flow rate (Qmax) of less than 12 milliliters per second and prostate volume between 30 and 100 milliliters. Each subject was treated with either PRX302 (3 microgram/mL) or placebo at a volume equivalent to 20 percent of the total prostate volume via a single ultrasound guided injection into each lobe of the prostate.

The trial's primary clinical endpoint of the study was to determine the efficacy of PRX302, as demonstrated at 90 days post-treatment, by a statistically significant improvement in IPSS from baseline when compared to placebo. IPSS is a validated primary clinical endpoint used to assess the treatment benefit in BPH trials. This index is measured on a 0 to 35 scale with 0 being defined as having no problems and 35 defined as the high end of severe symptoms.

Of the 73 per protocol efficacy evaluable subjects, 52 received PRX302 and 21 received placebo. The PRX302 arm showed an average IPSS improvement at 90 days of 9.1 (+/- 5.9) points versus an average IPSS improvement of 5.8 (+/- 5.4) points for the placebo arm, a statistically significant improvement of 3.3 points (p=0.0238, ANCOVA). Baseline average IPSS for the PRX302 and placebo groups were 23.5 and 22.9 points, respectively.

A sub-group analysis was performed for subjects with severe BPH (baseline IPSS(greater than)22, n=40). Results of this sub-group analysis showed that those treated with PRX302 had an average IPSS improvement at 90 days from baseline of 10.8 (+/- 6.0) versus an improvement of 5.8 (+/- 6.2) for those receiving placebo for an overall 5.0 point improvement over placebo.

No significant safety issues were identified in this study. There were no drug related serious adverse events or Grade 3 or greater adverse events reported in the study. PRX302 related adverse events were mild to moderate, transient in nature (resolved within days) and localized to the urinary tract. In addition, no sexual dysfunction was reported in any of the subjects.

A total of 92 subjects were enrolled on a 2-to-1 basis (treatment to placebo) and randomized based on their baseline IPSS and prostate size. At 90 days, the number of per protocol efficacy evaluable subjects was 21 (mean age of 64.5 years) of the 31 that were dosed at baseline in the placebo arm and 52 (mean age of 63.7 years) of the 61 dosed at baseline in the PRX302 arm. The decrease in efficacy evaluable subjects was due to protocol violations, medical interventions, or patient withdrawal and included three subjects that needed surgery to treat BPH (all from the placebo arm).

https://www.bionity.com/en/news/111668/protox-announces-positive-phase-2b-bph-results.html