Japanese drugmaker Shionogi & Co. shares rose the most in more than 20 months after disclosing its antiviral pill for Covid-19 was effective in a study.
Shionogi shares jumped 10% to 7,091 yen at 3 p.m. in Tokyo. Before today, the stock had fallen 21% this year.
Patients who received a high dose of the experimental drug were 80% less likely to be shedding infectious virus four days later than those given a placebo, while a lower dose cut the risk by 63%, the company said in earnings presentation documents on Monday. The results come from the second of three stages of clinical trials generally required to seek approval.
The viral load reduction is similar to Pfizer Inc.’s rival pill Paxlovid, and it was a surprise, said Akash Tewari, an equities analyst at Jefferies, in a note to clients. It’s either a fluke or a sign that Shionogi’s drug has a better profile than expected, he said.
Pfizer’s Paxlovid won an emergency use authorization in December from the U.S. Food and Drug Administration to treat mild-to-moderate coronavirus disease in people 12 years and older. The European Medicines Agency’s committee recommended granting a conditional authorization for the pill last week.
Shionogi is behind schedule in developing the pill after it struggled to find patients to enroll in clinical trials in Japan. The company submitted data from an earlier trial to the Pharmaceuticals and Medical Devices Agency in January and has begun talks on how it will submit data from later trials.