Adial Pharmaceuticals (Nasdaq: ADIL), a clinical-stage biopharmaceutical company headquartered in Glen Allen, Virginia, announced submission of an application for AD04 to the US FDA Commissioner’s National Priority Voucher (CNPV) Pilot Program on April 27, 2026. AD04 is a genetically targeted serotonin-3 (5-HT3) receptor antagonist in development for alcohol use disorder (AUD) in patients carrying pre-specified serotonin transporter and receptor polymorphisms.
The CNPV pilot, announced in 2025, operates outside the established Fast Track, Breakthrough Therapy, and Priority Review frameworks. It targets five designated US national health priorities and, if a voucher is granted, offers a collaborative review process modeled on a multidisciplinary tumor board structure, rolling submission, closer FDA engagement, and a target review timeline of one to two months following complete submission — compared to the standard ten to twelve months. Vouchers are non-transferable. AD04 had previously received both Fast Track and Breakthrough Therapy designations from the FDA, making the CNPV application a further attempt to compress the regulatory timeline ahead of a planned Phase III program.
The clinical case behind the application rests primarily on results from the ONWARD Phase III trial, the topline readout of which Adial released in July 2022. In the pre-specified genetically selected subgroup of heavy drinkers, AD04 produced an approximately 79% reduction in heavy drinking days from baseline versus placebo, and an 84% decrease in the proportion of patients meeting criteria for AUD severity. Exact p-values were not disclosed in the public announcement. The trial enrolled adults with AUD enriched for serotonin transporter polymorphisms, using Adial’s proprietary diagnostic genetic test to define eligibility. The Phase III study is registered as NCT04101227.
A peer-reviewed safety analysis drawing on the ONWARD dataset, published in April 2024, reported no statistically significant change in markers of liver injury — alanine aminotransferase, aspartate aminotransferase, or serum bilirubin — in patients receiving AD04 versus placebo. Elevated gamma-glutamyl transferase levels were observed in the AUD population but were not attributed to the drug. The publication also reported high medication compliance and a low dropout rate. In November 2024, Adial released topline results from the AD04-103 pharmacokinetics study, a Phase I evaluation in healthy volunteers comparing AD04 at 0.33 mg — a near-micro-dose formulation of ondansetron — against a 4 mg marketed reference tablet. The study confirmed dose-proportional pharmacokinetics across a threefold dose range and the absence of a clinically meaningful food effect, findings the company described as the final dataset required before an FDA meeting to define the next Phase III design.