The multi-center, placebo-controlled, phase IIa trial is designed to assess the safety, tolerability and efficacy of XP19986 in patients with gastroesophageal reflux disease (GERD).
The clinical trial is intended to test the ability of escalating single doses of a prototype sustained-release formulation of XP19986 to reduce reflux episodes. XenoPort expects to complete the trial in the first half of 2006.
XP19986 is designed to overcome the deficiencies of baclofen, a generic drug approved for the treatment of spasticity and marketed by Novartis as Lioresal. Baclofen is a racemic drug, a 50:50 mixture of R- and S-isomers. However, studies conducted by third parties have shown that the beneficial therapeutic properties of baclofen are attributable to the R-isomer of baclofen only.
Dr Ronald Barrett, XenoPort’s CEO, stated, “There is increasing recognition of the need for new GERD pharmacotherapies beyond that of the existing acid suppressing agents. We believe that the favorable pharmacokinetics and unique mechanism of action of XP19986 may address these unmet medical needs of GERD patients.”
XenoPort’s compound is a new chemical entity that is a transported prodrug of R-baclofen. XP19986 is designed to engage natural nutrient transport mechanisms found on intestinal cell membranes, thereby gaining efficient entrance into the bloodstream. It is then rapidly converted to R-baclofen by high-capacity enzymes. In addition to R-baclofen, the metabolic breakdown products of XP19986 are natural substances with favorable safety characteristics.