by BLOOMBERG

JAPANESE drugmaker Shionogi & Co. shares rose the most in five years after disclosing that its oral antiviral drug for Covid-19 was found to be effective in a study.

Shionogi shares jumped as much as 12% in early Tokyo trading Tuesday, the largest intraday gain since November 2016. The stock was down 21% this year as of Monday.

Patients who received a high dose of the experimental drug had 80% lower virus levels than those given a placebo after four days, while a lower dose cut the levels 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.

Shionogi is behind schedule in developing the oral pill after it didn’t apply for one last year due to lack of patients to enroll in clinical trials in Japan. The company submitted data from an earlier trial the Pharmaceuticals and Medical Devices Agency in January and began talks on how it will submit data from later trials.