GSK, Adolor Get Top-Line Results From Entereg/Entrareg Studies

GlaxoSmithKline and Adolor Corp. achieved top-line results from two Phase III registration studies (012 and 013) of alvimopan (Entereg/Entrareg) for the treatment of opioid-induced bowel dysfunction (OBD) in patients with chronic non-cancer pain. Study 012 achieved statistical significance for the primary endpoint — the proportion of patients who had a weekly average of three or more spontaneous bowel movements (SBM) defined as bowel movements with no laxative in the previous 24 hours and an increase from baseline of one or more SBMs a week over the 12-week treatment period. In patients treated with alvimopan 0.5 mg twice daily, 72% met the primary endpoint compared with 48% of patients receiving placebo. In patients treated with alvimopan 0.5 mg once daily, 61% met the primary endpoint compared with 48% of patients receiving placebo.

The 013 study had less statistical significance. Of the patients treated with alvimopan 0.5 mg twice and once daily, 63% met the primary endpoint compared with 56% of patients receiving placebo. As in the 012 study the weekly change from baseline in SBM frequency was numerically greater in both groups of alvimopan treated patients averaging 3.1 and 3.2 SBMs per week respectively, compared with 2.2 SBMs per week for those treated with placebo. These changes, evident by the first week of treatment, were sustained throughout the 12-week treatment period and returned to baseline following discontinuation of treatment.

Alvimopan was generally well tolerated in these studies. Adverse events (AEs) affecting the gastrointestinal (GI) tract were the most common in both studies occurring in 24-33% of alvimopan-treated patients, compared with 22% on placebo.