Aardvark sinks 65% on data from halted trial of hunger drug; FDA to allow new tests

Aardvark Therapeutics stock plunged 65% on Friday. Its experimental drug to suppress hunger in people with Prader-Willi syndrome showed only a modest benefit versus placebo, according to data released from an early-terminated phase III clinical trial. The findings are not definitive, though: Aardvark paused testing in February following cardiac safety issues, but on Thursday U.S. regulators cleared clinical development to resume.

Aardvark fell 65% on the Nasdaq on Friday to $1.39 per share. The stock continued to decline after Monday’s opening bell and was down 11.5% at the time of this writing.

The selloff followed the company’s release of data from the final, phase III clinical trials of its lead drug candidate, ARD-101. Aardvark tested the treatment in patients with Prader-Willi syndrome, a rare genetic disorder characterized, among other symptoms, by constant hunger that can lead to severe obesity without strict controls.

The findings showed a short-term reduction in hunger with the drug. Within two weeks of stopping treatment, hunger scores returned close to baseline. The placebo group showed less rebound toward baseline, according to the press release.

However, the findings are not definitive, the company stressed. In February, Aardvark was forced to pause testing after electrocardiogram changes were detected in a separate study involving healthy volunteers. The U.S. Food and Drug Administration subsequently placed the program on clinical hold in May. As a result, the trial enrolled only around 74% of its planned participants, which left insufficient data to establish the drug’s efficacy.

Following additional safety studies, the FDA lifted the clinical hold on ARD-101 on Thursday. Aardvark stated that it plans to meet with regulators to agree on a new phase III trial design. The management expects clinical development of ARD-101 to resume in 2027.

Aardvark completed an IPO on the Nasdaq in February 2025. The stock has since lost almost 91% versus its IPO price. Five Wall Street analysts still recommend buying the stock, versus three “hold” ratings and two bearish recommendations. The average target price is $9.13 per share, implying almost 557% upside following the Friday selloff.