Single administration of PRX302 as a short outpatient procedure provided sustained benefit over 12 months
SAN DIEGO, CA and VANCOUVER, Oct. 9, 2012 /PRNewswire/ - Sophiris Bio Inc. (TSX: SHS) today released top line data from the 12 month follow up of patients receiving PRX302 for the treatment of benign prostatic hyperplasia (BPH, or enlarged prostate) in a Phase 2b study (TRIUMPH). PRX302 produced a clinically significant improvement in the subjective symptom score (International Prostate Symptom Score, or IPSS) and the objective measure of mean peak urinary flow rate (Qmax) sustained over 12 months. As previously reported, the trial met the primary clinical endpoint of the study, which was to demonstrate the efficacy of PRX302 at 90 days post-treatment by a statistically significant improvement from baseline in IPSS when compared to placebo (vehicle only injection). Consistent with the results previously reported for this study, PRX302 continued to be well tolerated with no erectile function side effects during the 12 months following treatment.
PRX302 treatment resulted in approximately 8 to 9-point average reduction of IPSS that was sustained over 12 months. The IPSS is a patient self-administered questionnaire of lower urinary tract symptoms with a possible range of 0 to 35 points, with 0 being no symptoms and 35 being the high end of severe symptoms. This average improvement in IPSS was a clinically meaningful 2.8 to 4.1 point reduction over and above the IPSS improvement observed in the placebo group. In addition, PRX302 treatment resulted in a ~3 mL/sec average increase in Qmax, which was sustained over 12 months. Both IPSS and Qmax are validated clinical endpoints used for BPH product regulatory approvals.
PRX302 was well tolerated in this study with patients who had moderate to severe lower urinary tract symptoms due to BPH, about half of whom had previously taken oral medication for BPH. The side effect profile was favorable with most of the side effects attributed to the injection procedure itself and not related to drug toxicity.
"PRX302 is demonstrating potential as an alternative treatment to oral medications as well as surgical procedures," said Randall Woods, President and CEO of Sophiris Bio. "Patients commonly stop oral medications for lack of efficacy or side effects, or are non-compliant with taking daily pills. 'Minimally invasive' procedures that aim to remove excess tissue in the prostate require anesthesia and catheterization, which limit access for patients and add to cost. PRX302 has the potential to be safer than surgical procedures, more efficacious than oral medications, and with a sustained treatment effect for 12 months."
Woods added: "We expect to confirm these results in a pivotal study that closely resembles the design of this Phase 2b study and includes the same proven clinical endpoints used for prior regulatory approvals of drugs for BPH."
Benign prostatic hyperplasia (BPH) is an enlarged prostate gland often resulting in a constricted or partially blocked urethra that can lead to pain, discomfort and other complications with urination. BPH occurs in almost all men as they age, with 50% of men over age 50 and 70% of men over age 70 complaining of symptoms. If untreated, it can lead to urinary problems such as:
- Trouble starting and stopping urination
- Frequent and irregular needs to urinate, particularly in the night while sleeping
- A weak urine stream
- Painful urination or urinary retention, leading to infections, stones or kidney damage
In the US, approximately 11 million men have been diagnosed with BPH. Five million of these patients are bothered enough by symptoms to seek treatment, such as daily pharmaceuticals, but these treatments often lack sustainable efficacy and are associated with undesirable side effects including sexual dysfunction. With current pharmaceutical treatments, symptoms will usually return if medication is discontinued. More aggressive treatment options include invasive surgical procedures that may be successful at treating BPH but may be accompanied by operative complications. Any type of prostate surgery can cause side effects, such as semen flowing backward into the bladder (retrograde ejaculation), loss of bladder control (incontinence) and impotence (erectile dysfunction).
PRX302 is designed to be a once-a-year treatment for the long-term relief of BPH symptoms without causing sexual dysfunction or sacrificing quality of life. PRX302 is precisely targeted to the prostate tissue constricting the urethra without damaging neighboring healthy tissue. It is delivered by a 1-3 minute injection completed during an office visit. PRX302 has been engineered to be activated only by the prostate specific antigen (PSA) enzyme that is produced in large amounts in the prostates of men with BPH. Once activated, PRX302 forms disruptive pores in the membranes of prostate cells, thus creating a highly targeted, localized and more convenient approach to eliminating prostate cells constricting the urethra.
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 large potential demand. 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 advised by world-leading urologists, backed by experienced investors, and led by a team that has achieved more than twenty drug approvals including drugs with annual sales in excess of $1 billion. For more information, please visit www.sophirisbio.com.
Certain statements included in this press release may be considered forward-looking, including statements about the potential for PRX302. 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, 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 inherent in late stage drug development and risks relating to obtaining FDA and other regulatory approvals as well as risks 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 in this press release, whether as a result of new information, future events or otherwise.
SOURCE Sophiris Bio, Inc.