Sophiris Bio, a urology company, has announced that PRX302, a treatment for benign prostatic hyperplasia (BPH), was well-tolerated for three months following a transrectal injection.

The transrectal safety study was designed to assess the safety and tolerability of delivering PRX302 via a transrectal route of administration using transrectal ultrasound (TRUS).

The results support the use of a TRUS-guided injection for the delivery of PRX302 directly into the prostate; previous studies used a transperineal route.

Sophiris Bio CEO Randall Woods said that the decision to move to a transrectal route was made based on the input of advisors and leading urologists treating patients with BPH.

“The transrectal route enables PRX302 to be administered by a urologist in an office based setting, in a brief procedure that does not require catheterisation,” Woods said.

“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.”

The ongoing placebo controlled, double-blind, Phase I-II study, which randomised 40 patients within one of four ascending dose cohorts, has found PRX302 continues to be well-tolerated with an adverse event profile similar to previous clinical studies using a transperineal injection.

The multicentre study also observed the improvement in the International Prostate Symptom Score (IPSS) in all cohorts.

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, according to the company.