Shares in Pharvaris plunged Monday after the Swiss biotechnology company revealed the Food and Drug Administration has suspended testing of its most advanced drug for the rare disease hereditary angioedema.
After reviewing nonclinical data, the regulator put two studies of the drug, dubbed PHA121, on hold in the U.S., Pharvaris said in a brief statement Monday. The company did not specify what specific data spurred the agency’s alarm, but noted the FDA plans to provide it with a formal letter within 30 days.
“We are fully committed to working closely with the FDA to address the agency’s concerns,” said Berndt Modig, Pharvaris’ CEO, in the statement.
Shares in the Zug, Switzerland-based company fell by more than a quarter in Monday morning trading on the Nasdaq stock exchange, erasing about $150 million in market value.
Pharvaris is testing PHA121 in two clinical trials that were recruiting participants in the U.S., as well as an extension study that had not yet begun enrollment. The drug is designed to both treat and prevent attacks caused by hereditary angioedema, or HAE, a genetic condition that’s characterized by painful and unpredictable swelling.
Pharvaris is developing PHA121 in softgel capsule and extended release formulations of the same active ingredient. The two studies that were enrolling involved the softgel capsule version.
Joseph Schwartz, an analyst at SVB Securities, noted that there have been safety concerns around an approved HAE drug called Firazyr, which works in a similar fashion as PHA121. But, he added in a note to clients, Pharvaris has said it hasn’t seen any Firazyr-related toxicity in testing and submitted toxicity studies to the FDA.
Several treatments exist for HAE, but Pharvaris is one of several drugmakers working to develop more effective or convenient therapies. Australian pharmaceutical company CSL this month announced plans to ask the FDA for approval of a once-monthly injection for the disease, while Intellia Therapeutics, KalVista Pharmaceuticals and Ionis Pharmaceuticals are also advancing candidates of their own.
Analysts at Jefferies wrote in a note to clients that the hold for Pharvaris should benefit KalVista, shares in which rose by more than 10% Monday morning. KalVista’s HAE drug, an oral medicine, was also previously placed on clinical hold, which was lifted after four months in September 2021.