DBV Technologies SA said on Friday its peanut allergy treatment did not meet the main goal in a highly anticipated late-stage study, sending its U.S.-listed shares sharply down.
Nasdaq-listed shares of the French drug developer plunged 60.5 percent to $19 in extended trading.
The trial, which tested a 250 microgram stick-on patch called Viaskin Peanut, in 356 children between the ages of 4-11, missed the main goal of achieving a certain tolerance to peanut protein.
Aimmune is expected to announce results of its late-stage trial early next year.
Preliminary results of DBV’s trial show 12 months of the treatment resulted in 35.3 percent of patients achieving a certain tolerance, versus a higher-than-expected 13.6 percent response from a placebo group.
However, DBV said the results showed a statistically significant response with a favorable tolerability profile.
Plans to submit a marketing application for the patch to the U.S. Food and Drug Administration (FDA) next year remain unchanged, the company said.
DBV is also testing a similar patch to treat cow milk-related allergies in a mid-stage trial, the results of which are expected early next year.
Leerink analyst Dae Gon Ha estimated DBV’s peak sales, including the peanut and milk allergy patches, of about 1.8 billion euros ($2.12 billion) in 2027.
There are currently no U.S. regulator-approved treatments for peanut allergies, the leading cause of death from food-induced allergic reactions in the United States.
The market is desperate for recourse, experts say, as peanut allergies have more than doubled in children from 1997 to 2008, and affect about two percent, American children.
Those afflicted risk potentially fatal anaphylaxis, a severe allergic reaction, even if exposed to trace amounts of peanut protein.
Viaskin Peanut, which must be replaced daily, delivers peanut protein to patients’ immune systems via the skin, desensitizing them to small doses of the allergen over time.
Unlike an oral drug, the patch avoids contact with the bloodstream, lessening the risk of adverse reactions, DBV told Reuters.
Earlier this month, Aimmune said it planned to test its pill in a mid-stage trial with Regeneron Pharmaceuticals Inc’s and Sanofi’s drug dupilumab.
(Reporting by Tamara Mathias in Bengaluru; Editing by Shounak Dasgupta)