SAN DIEGO, CA and VANCOUVER, Aug. 31, 2012 /PRNewswire/ - Sophiris Bio Inc. (TSX: SHS) today announced data from its transrectal safety study, in which PRX302, the company's drug candidate for the treatment of Benign Prostatic Hyperplasia (BPH or enlarged prostate), was well tolerated through three months following a transrectal injection. The results support the use of a transrectal ultrasound (TRUS) guided injection for the delivery of PRX302 directly into the prostate. This route of administration will be used in future clinical trials of PRX302 in patients with BPH.

The primary objective of this small study was to evaluate the safety and tolerability of delivering PRX302 via a transrectal route of administration using TRUS. The data allow an assessment as to whether the safety profile from the transrectal delivery was similar to that observed with the transperineal route of administration, which had been used in all previous clinical studies with PRX302.

"The decision to move to a transrectal route of delivering PRX302 directly into the prostate as opposed to transperineal was made based on the input of our advisors and leading urologists treating patients with BPH," said Randall Woods, CEO of Sophiris Bio. "The transrectal route enables PRX302 to be administered by a urologist in an office based setting, in a brief procedure that does not require catheterization. To date 126 patients with BPH have been treated with PRX302 with a similar safety and tolerability profile between the transrectal and transperineal routes of administration."

This ongoing randomized, placebo controlled, double-blind, multicenter, Phase 1-2 study enrolled 40 patients with moderate to severe BPH. Patients were randomized within one of four ascending dose cohorts, and the decision to move to the next higher dose was guided by an independent data monitoring committee that reviewed the safety data through Day 15. The primary endpoint of the study was to evaluate the 3-month safety and tolerability of escalating doses of PRX302, although patients are to continue to be evaluated through Month 12. The data from all four cohorts through Month 3 indicate that PRX302 continues to be well tolerated with an adverse event profile similar to that seen in previous clinical studies using a transperineal injection. No drug-related sexual function adverse events were observed, and there were no reports of bacteremia or sepsis. Improvement in the International Prostate Symptom Score (IPSS) was observed in all cohorts. Given the small sample size of eight patients on PRX302 and two patients on placebo in each cohort, no statistically significant differences were observed.

About BPH

BPH is a $5 billion market with more than 4 million patients treated each year in the U.S. alone. Despite available medical treatments and surgical options, no single solution provides quick, long-term relief of symptoms without serious unwanted side effects. Pharmaceutical product sales in the U.S for BPH are $4 billion annually; however, current treatments lack sustainable efficacy and/or are associated with undesirable side effects including sexual dysfunction. More aggressive treatment options include invasive surgical procedures that may be successful for treating BPH but can also result in nerve damage and sexual dysfunction.

About PRX302

PRX302 is designed to be a single treatment for the long-term relief of BPH symptoms, such as restricted urinary flow from enlarged prostate, without causing sexual dysfunction or sacrificing quality of life.

PRX302 is highly targeted to prostate tissue. It is delivered directly to the prostate tissue via localized injection and it is activated selectively by active Prostate-Specific Antigen (PSA) found only in prostate tissue. PRX302 has shown meaningful improvements in the IPSS and peak urinary flow rate (Qmax) in a randomized placebo-controlled Phase IIb trial (TRIUMPH study). IPSS has been a primary endpoint and Qmax has been a secondary or co-primary endpoint for prior BPH drug approvals. To date 126 patients with BPH have been treated with PRX302.

About Sophiris

Sophiris Bio Inc. is a urology company developing a late-stage, highly targeted treatment for benign prostatic hyperplasia (BPH or enlarged prostate), an unsatisfied market with blockbuster potential. PRX302, the company's lead candidate for BPH, is designed to be as efficacious as pharmaceuticals, less invasive than the surgical interventions, and without the sexual side effects seen with existing treatments. Sophiris is planning to begin a pivotal trial by the end of 2012. Sophiris is advised by world-leading urologists, backed by experienced investors, and led by a team that has achieved more than twenty drug approvals including several blockbusters. For more information, please visit www.sophirisbio.com.

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 Sophiris' current beliefs as well as assumptions made by and information currently available to Sophiris and relate to, among other things, future safety data results, future efficacy trial results, anticipated timelines for future trials, anticipated financial performance, business prospects, strategies, regulatory developments, available competitive treatments for BPH, 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 Sophiris in its public securities filings; actual events may differ materially from current expectations. Sophiris disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

SOURCE Sophiris Bio, Inc.