Aardvark Therapeutics said the FDA placed a full clinical hold on the ARD-101 IND program for Prader-Willi syndrome after the company’s March 2026 voluntary pause, affecting all ongoing Phase 3 studies.
Written By: Regulatory Desk
Aardvark Therapeutics announced that the U.S. Food and Drug Administration has placed a full clinical hold on the investigational new drug (IND) application for ARD-101, following the company’s voluntary pause of the program on March 23, 2026. The program-wide pause followed an earlier halt of the Phase 3 HERO trial on March 3, 2026.
The clinical hold applies to all ongoing studies conducted under the IND, including the Phase 3 HERO trial (AVK-101-301) (NCT06828861) evaluating ARD-101 for hyperphagia in patients with Prader-Willi Syndrome, as well as the Phase 3 open-label extension (OLE) study (AVK-101-302) (NCT07197034).
Aardvark stated that it is continuing discussions with the FDA to address the agency’s concerns and determine a potential path forward for the ARD-101 development program.
Company founder and chief executive officer Dr. Tien Lee said the company is working collaboratively with regulators to review the available data while maintaining patient safety as its primary focus. He added that Aardvark remains committed to the Prader-Willi syndrome community and to advancing ARD-101 as a potential treatment option for the underserved patient population.
Alongside its regulatory discussions, Aardvark plans to unblind clinical data collected from both the HERO and OLE trials. The company said the review will help assess the overall efficacy and safety profile of ARD-101 and support decisions regarding the future of the program.
As of February 27, 2026, the company had enrolled and dosed 68 patients in the randomized HERO study and 19 patients in the OLE trial.
ARD-101 is an oral small-molecule therapy designed to stimulate gut-peptide hormone release through activation of bitter taste receptors. The investigational therapy has been studied as a treatment for hyperphagia associated with Prader-Willi syndrome, a rare genetic disorder marked by chronic and excessive hunger.
Aardvark also reported cash, cash equivalents, and short-term investments totalling $91.2 million as of March 31, 2026. The company said the current cash position is expected to support operations into mid-2027.
Prader-Willi Syndrome is a rare genetic disorder affecting approximately one in 10,000 to 30,000 people and is characterized by persistent excessive hunger, developmental challenges, and severe obesity-related complications.
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