A Phase 1, Open-Label, Randomized, Two-Part Study in Healthy Adult Volunteers to Evaluate the Bioavailability of the Maribavir Powder for Oral Suspension, as Well as Food Effect and Impact of Rabeprazole

The relative bioavailability and impact of food and the proton pump inhibitor rabeprazole on the pharmacokinetics of a maribavir powder-for-oral-suspension formulation was investigated in a Phase 1 open-label study in healthy adult volunteers. A single 200-mg maribavir dose was administered as the commercial tablet (Treatment A), powder formulation (Treatment B), or powder formulation with a high-fat/high-calorie meal (Treatment C) in Part 1, and as the powder formulation alone (Treatment D) or following administration of rabeprazole 20 mg once daily for 5 days (Treatment E) in Part 2. Maribavir maximum plasma concentration following Treatment B was 18% lower versus Treatment A, whereas the area under the concentration-time curve (AUC) from time 0 to the last quantifiable concentration or infinity were similar. Maribavir maximum plasma concentration, AUC from time 0 to the last quantifiable concentration, and AUC from time 0 to infinity were reduced by 42%, 18%, and 18% (Treatment C vs Treatment B), and by 51%, 30%, and 11% (Treatment E vs Treatment D), respectively. A clinically significant reduction in maribavir exposure is not expected when maribavir powder formulation is taken with food or proton pump inhibitors. Participants assessed the powder for oral suspension as easy to swallow and having an acceptable taste/texture. Safety profiles for maribavir formulations in this study were consistent with those previously published.