XenoPort Reports Positive Results From Arbaclofen Placarbil Trial

XenoPort has reported positive preliminary results from a phase-II clinical trial of arbaclofen placarbil (AP), also known as XP19986, for the treatment of patients with spasticity due to spinal cord injury.

Twice daily (BID) 20mg and 30mg doses of AP showed significant improvements, as compared to placebo for the primary endpoint of the study.

This phase-II clinical trial was a randomized, double-blind, placebo-controlled, crossover study that enrolled 37 subjects at ten sites in the US and Canada.

Patients received either AP (10, 20 or 30mg BID) or placebo in the first treatment segment of the two-segment crossover design. Each treatment segment included a titration period, followed by at least one week at the target dose, at which time efficacy assessments were performed (day 17 of each treatment segment). Each treatment segment also included a down-titration period, and there was a three-day washout between treatment segments. AP was well tolerated at all dose levels, said the company.

Ronald Barrett, CEO of XenoPort, said: “These results add to a growing body of evidence suggesting the efficacy and safety of AP in multiple indications.”

“We believe AP offers the potential for a differentiated treatment of spasticity in SCI patients. We intend to seek guidance from regulatory authorities regarding future trial designs and safety database requirements for a clinical program leading to a new drug application for AP as a potential treatment of spasticity in SCI patients and possibly other spasticity populations,” he added.