ARD-101 clinical hold lifted by FDA

Aardvark Therapeutics said the Food and Drug Administration has lifted the clinical hold on its Investigational New Drug application for ARD-101, an oral drug candidate for hyperphagia in Prader-Willi syndrome. The San Diego company announced the decision on Oct. 22, 2026. The news clears the way for ard-101 to resume clinical development after months on hold.

"We are pleased that the FDA has lifted the clinical hold on ARD-101, allowing us to continue advancing our clinical development program," said Tien Lee, M.D., founder and chief executive officer of Aardvark. "With strong alignment and collaboration with the FDA, we completed the work necessary to allow for the resumption of clinical studies."

Lee said people living with PWS and their families continue to face profound unmet need, and the company looks forward to working with the FDA as development moves ahead.

The timeline stretched across most of 2026. Aardvark first paused dosing on its own in February after the ECG changes showed up in routine monitoring of healthy volunteers. The FDA then imposed its formal hold in May. The company spent the following months running the new cardiac study and the laboratory sodium-channel work the agency wanted to see before it would let trials restart. Aardvark has already unblinded the data gathered before the pause, covering both the HERO trial and its open-label extension, to look at the full set of efficacy and safety information available.

Why the ard-101 hold was imposed

Aardvark voluntarily paused dosing in the Phase 3 HERO trial (Hunger Elimination or Reduction Objective) and its open-label extension on Feb. 27, 2026, after reversible electrocardiogram changes appeared during routine safety monitoring in a separate study in healthy volunteers. The FDA imposed a formal clinical hold on both trials in May 2026.

Working with the FDA, the company ran a new electrocardiogram study in additional healthy volunteers and an in vitro cardiac sodium channel (NaV1.5) study. No cardiac events were observed in the completed study at ard-101 doses of 200 mg and 400 mg twice daily, the company said.

What cleared ard-101 to resume

Aardvark Therapeutics said it plans to resume clinical development of ard-101 in patients with Prader-Willi syndrome after further engagement with the FDA on the Phase 3 trial design. The company previously unblinded the data collected across the terminated Phase 3 HERO trial and the open-label extension to assess the available efficacy and safety data.

The company cautioned that both trials were terminated early and were not powered to assess efficacy. It also flagged risks ahead: the FDA may not agree with its proposed Phase 3 program or may require additional studies, earlier trial results may not predict future outcomes, and the company could use its capital resources sooner than expected.

About hyperphagia and Prader-Willi patients

ARD-101 is an oral, small-molecule drug designed to stimulate the release of gut-peptide hormones by activating bitter taste receptors. The company is developing the drug to treat hyperphagia, the insatiable hunger that characterizes Prader-Willi syndrome, a rare genetic disorder.

Aardvark (Nasdaq: AARD) is a clinical-stage biopharmaceutical company developing small-molecule drugs intended to suppress hunger. The company describes hunger, the discomfort from not having eaten recently, as a neural signaling pathway separate from appetite, the reward-seeking desire for food. Its programs explore hunger-associated conditions and possible complementary uses alongside anti-appetite therapies.

Webcast set for Oct. 23

The company will host a live conference call and webcast for investors on Oct. 23, 2026, at 8:00 a.m. ET to review the available ard-101 data from the terminated HERO and OLE trials. Investors can register for the call in advance, and a recording will be posted in the Investors section of the company's website afterward.