VANCOUVER, Jan. 12 – Protox Therapeutics Inc. (TSX: PRX), a leader in the development of receptor targeted fusion proteins, today announced the initiation of a double-blinded placebo controlled Phase 2 study of PRX302 (study name: TRIUMPH) in patients with benign prostatic hyperplasia (BPH), a painful and bothersome urological condition that affects more than 50 million men worldwide. The trial will evaluate the efficacy of PRX302 versus placebo using the optimal treatment volume established in the open-label Phase 2 study results announced in November, 2008.

"Results from our open-label Phase 2 study demonstrated that PRX302 has the potential to establish a new standard of care for the treatment of BPH," said Dr. Fahar Merchant, President and Chief Executive Officer of Protox. "With results from TRIUMPH expected in the second half of 2009, we are confident this study will validate the value of PRX302 to our potential partners, and most importantly, patients suffering from BPH."

The trial's primary endpoint will be to determine efficacy of PRX302 as demonstrated by a statistically significant change in International Prostate Symptom Score (IPSS) from baseline when compared to placebo. Secondary endpoints will be the measurement in change from baseline of the Quality of Life (QoL) score, Peak Urinary Flow Rate (Qmax) and Post-Voiding Residual urine volume (PVR) when compared to placebo. The trial will also continue to assess safety and tolerability of PRX302. Results from the three month follow-up period of the Phase 2 study released in November, 2008 were very positive, with PRX302 demonstrating significant symptomatic relief while maintaining an excellent safety profile in men with moderate to severe BPH. In addition, 12 month follow-up results from the Phase 1 BPH study, completed in October 2008, indicated that PRX302 continues to show durable therapeutic benefit for at least one year following a single treatment.

   

About TRIUMPH

In this double-blinded placebo controlled Phase 2 study, up to 72 patients with moderate to severe BPH will be randomized 2:1 (treatment:placebo). Each patient will either receive PRX302 (3(micro)g/ml) or placebo at a volume equivalent to 20 percent of the total prostate volume with a minimum 1.5 mL per deposit. Dosing for each arm will be delivered via a single ultrasound-guided injection into each lobe of the prostate. Eligible patients will not have received alpha-blockers for at least 4 weeks prior to treatment and will not have been treated with 5 alpha-reductase inhibitors. Efficacy will be assessed based on symptomatic relief, prostate shrinkage and urinary flow measurements.

   

About BPH

BPH is a common urological condition characterized by painful and bothersome symptoms that include difficulty in initiating a urine stream, a sense of urgency, dribbling, incomplete emptying of the bladder, waking several times during the night to urinate and sometimes the presence of blood in the urine. More than half of all men will have symptoms of BPH by the age of 60 and as many as 90% may suffer from BPH after the age of 80. Current oral therapies mainly provide symptomatic relief, may take months before they take effect and can trigger a range of side effects including sexual dysfunction and hypotension. It is estimated that in the seven largest global markets approximately 10 million men are treated annually with oral therapies and these products encompass approximately U.S. $3 billion of sales each year. Surgical options, including minimally invasive procedures, can cause sexual dysfunction, incontinence as well as other more serious procedure-related effects. Surgical measures can require significant recovery time and may require catheterization for up to several weeks post-treatment. Nearly 600,000 surgical procedures are conducted annually in the seven largest markets.

   

About PRX302

PRX302 is the lead drug in the company's PORxin(TM) technology platform. PORxin drugs are pore-forming pro-drugs that are activated by specific proteases produced at elevated levels on the surface of target cells. PRX302 has been generated by engineering the naturally occurring toxin proaerolysin so that it is activated by prostate-specific antigen (PSA), an enzyme that is overproduced in patients suffering from prostate cancer and BPH (benign prostatic hyperplasia or enlarged prostate). Once activated, the drug punches holes in the cells causing the contents to leak out and ultimately cell death.

   

About Protox

Protox Therapeutics is a leader in advancing novel, receptor targeted fusion proteins. Two novel drug candidates derived from the company's INxin(TM) and PORxin(TM) platforms are being developed in three clinical programs. A Phase 2a clinical trial evaluating PRX321 (INxin) for the treatment of primary brain cancer has been completed and the drug has received Fast Track Designation and Orphan Drug Status from the US FDA and EMEA. A phase 2a clinical trial evaluating PRX302 (PORxin) for the treatment of localized prostate cancer is ongoing and positive final Phase 2 results from Protox's lead program using PRX302 to treat benign prostatic hyperplasia (enlarged prostate) were recently released. Protox is also collaborating with the U.S. National Institutes of Health (NIH) on a research program focused on the discovery of next generation fully human targeted therapeutics.

Certain statements included in this press release may be considered forward-looking. Such statements involve known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements to be materially different from those implied by such statements, and therefore these statements should not be read as guarantees of future performance or results. All forward-looking statements are based on Protox' current beliefs as well as assumptions made by and information currently available to Protox and relate to, among other things, anticipated financial performance, business prospects, strategies, regulatory developments, market acceptance and future commitments. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Due to risks and uncertainties, including the risks and uncertainties identified by Protox in its public securities filings; actual events may differ materially from current expectations. Protox disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.