Aardvark Therapeutics Shares Drop 56.71% After Phase 3 Trial Results

Aardvark Therapeutics shares fell 56.71% to $1.70 at publication on Friday after the company released exploratory efficacy results from its terminated Phase 3 HERO trial and open-label extension study. Benzinga Pro data showed that the shares reached a new 52-week low. Aardvark unblinded the collected data to assess ARD-101's safety and clinical profile in patients with Prader-Willi syndrome.

The HERO trial randomized 67 participants against a planned enrollment of 90 before Aardvark terminated the study early. Participants receiving ARD-101 showed a small decrease in Hyperphagia Questionnaire for Clinical Trials scores relative to placebo during the second dose-escalation week. Hyperphagia causes extreme hunger in people with Prader-Willi syndrome, a rare genetic disorder. Hunger scores approached baseline again after patients discontinued ARD-101. The placebo group experienced a smaller rebound.

Participants switching from placebo to ARD-101 in the open-label extension recorded an average six-point decline in hunger scores. Assessments by caregivers and clinicians followed the same pattern. Founder and CEO Tien Lee said the early termination and incomplete data prevent definitive conclusions. However, Lee said the exploratory safety and efficacy findings were directionally consistent and supported confidence in continuing ARD-101 development for Prader-Willi syndrome.

Patients generally tolerated ARD-101, with most adverse events classified as mild or moderate. Aardvark identified one serious cardiac adverse event in a patient receiving 800 mg twice daily while also taking pitolisant. The FDA attributed the event to a drug-drug interaction. Aardvark plans to restart patient dosing below 800 mg twice daily. Aardvark also plans to seek an FDA meeting to align the Phase 3 program and move ARD-101 toward possible regulatory approval.

The FDA lifted the clinical hold on ARD-101 for Prader-Willi syndrome on Thursday. Aardvark had voluntarily suspended the Phase 3 HERO trial in February after routine safety checks detected reversible cardiac observations at doses above the target therapeutic level. The FDA imposed a full clinical hold in May on every ongoing study under the investigational new drug application. The hold covered the Phase 3 HERO trial for hyperphagia associated with Prader-Willi syndrome and the open-label extension study.