Vivozon said that it has started recruiting patients for phase 3b clinical trial of Opiranserin, its non-narcotic analgesics for treating patients who had undergone a bunionectomy.

The trial aims to register 300 patients by the end of October and publish top-line results in December this year or January next year. Depending on the outcome of the trial, the company will decide on conducting additional clinical phase 3 and open-label safety studies in the future.

The phase 3b clinical trials' launch comes after the company failed to see a statistically significant difference in the 12-hour pain margin, which was the primary endpoint of the study.

At the time, the company claimed that it had failed to meet the primary endpoint of the trial due to the small patient pool of the study.

Vivozon said that the research was a success in terms of exploratory efficacy as the drug still showed excellent efficacy in patients with a pain level of 7 or higher in pain intensity.

To maximize the chances of clinical success for the treatment, the company has refined the design of the Phase 2b trial.

In the new trial, the company plans to enroll patients with a pain level of 4 or higher after surgery, while significantly reducing the dose of opioids administered as a remedy to secure a difference from the placebo group.

"Considering that a second viral wave may hit the country, we will complete registration in three to four months," Vivozon CEO Lee Doo-hyun said.