Pfizer’s COVID-19 treatment pill showed no significant statistical benefit when used to prevent the disease, according to the company’s press office.

“In this study, compared to placebo, Pfizer observed a 32% and 37% reduction in the risk of coronavirus infection in adults who received Paxlovid for five and ten days, respectively, to prevent infection. These results, however, were not statistically significant, and therefore the primary endpoint of reducing the risk of confirmed and symptomatic COVID-19 infection in adults exposed to the virus through household contact was not met,” the company said in a statement.

Paxlovid is currently approved or authorized for conditional or emergency use in more than 60 countries for the treatment of high-risk COVID-19 patients.

Shares of PFE fell 2.85% to $49.07 on April 29. The stock is down 0.88% on the premarket.