Introduction: Motilin-receptor agonists are prokinetics; whether they relieve the symptoms of functional dyspepsia is unknown. We aimed to test the efficacy of the motilin agonist ABT-229 in functional dyspepsia patients with and without delayed gastric emptying.
Methods: Patients were randomized with postprandial symptoms and documented functional dyspepsia by endoscopy (n=589 in intention-to-treat analysis). Patients were assigned to either the delayed or normal gastric emptying strata, based on a validated 13C octanoic acid breath test. Patients were then further randomized within each strata, to receive one of four doses of ABT-229 (1.25, 2. 5, 5 or 10 mg b.d. before breakfast and dinner) or placebo for 4 weeks, following a 2-week baseline. The primary outcome was the assessment of change in symptom severity over the 2 weeks from baseline to final visit, based on a self-report questionnaire measuring severity on visual analogue scales.
Results: Baseline characteristics across the treatment arms were very similar. No significant differences in the upper abdominal discomfort severity score (maximum 800 mm) were observed for any active treatment arm vs. placebo (mean change from baseline -139, -141, -145, -160 and -134 mm for placebo, 1.25, 2.5, 5, and 10 mg, respectively, at 4 weeks by intention-to-treat). More patients on placebo reported a good or excellent global response than patients on 1.25 or 5 mg of active therapy (both P < 0.05). The results were very similar in those with and without delayed gastric emptying. Helicobacter pylori status did not predict response. Excluding patients with any baseline heartburn (total remaining n=240), ABT-229 10 mg was inferior to placebo in relief of upper abdominal discomfort.
Conclusions: ABT-229 was of no value for relief of symptoms in functional dyspepsia, compared with placebo.