Prostate Rx Back on the Road to Approval

PRX302 found to improve benign prostatic hyperplasia symptoms in late-stage trial

(RxWiki News) The frequent nighttime bathroom trips and other symptoms tied to an enlarged prostate can be a nuisance for many men. But an experimental new drug may soon be here to help.

Biopharmaceutical company Sophiris Bio, Inc., recently announced that its sole drug in development, PRX302, has met its main goal of significantly improving benign prostatic hyperplasia (BPH) symptoms in a late-stage clinical trial. This announcement comes nearly one year after the company's interim analysis suggested the drug would fail.

The drug did not achieve its secondary goal of significantly improving the flow of urine in these men, however.

BPH is an age-related prostate gland enlargement. If left untreated, BPH can block the flow of urine out of the bladder and cause bladder, urinary tract or kidney infections. While there are several effective treatments for BPH — including drugs, therapies and corrective surgery — these treatments often carry a high risk of side effects like sexual dysfunction and heart problems, according to the company.

By comparison, the company said PRX302 has demonstrated a significant improvement in International Prostate Symptom Score (IPSS) over the 12-month trial — without any evidence of treatment-related sexual or cardiovascular side effects.

The most common side effects included painful and frequent urination, blood in the urine, fever and pain.

"An ... improvement in IPSS total score over 12 months indicates that patients are experiencing a significant relief of their BPH symptoms and improvement in their quality of life following a single treatment with PRX302," said Allison Hulme, PhD, chief operating officer and head of research and development at Sophiris Bio, in a press release.

Dr. Hulme said that replicating these results in another late-stage trial may be enough evidence of PRX302's value to apply for marketing approval from the US Food and Drug Administration (FDA).

According to the National Institutes of Health, BPH is an extremely common condition. So common, in fact, that it's estimated that all men will develop an enlarged prostate if they live long enough. Currently, BPH affects about half of men in their 50s and up to 90 percent of men older than 80.

"The combination of the efficacy and safety profile makes PRX302 a particularly compelling potential option for men suffering from BPH and may help men avoid more invasive, surgical procedures," said Randall Woods, president and CEO of Sophiris, in the release.

The company is also studying the drug as a potential treatment for prostate cancer.

Review Date: 
November 11, 2015