Il-Yang Pharmaceutical said Thursday that its chronic myelogenous leukemia (CML) drug, Supect (Radotinib), has failed to show efficacy in treating Covid-19, in phase 3 clinical trial conducted by a Russian partner R-Pharm.

R-Pharm decided not to proceed to receive marketing approval for Supect as Covid-19 treatment in Russia. The Ministry of Health of the Russian Federation (MOH) concluded that the drug did not show the superior effect to recommended therapy.

Supect is a drug developed by Il-Yang Pharmaceutical for leukemia patients, and the company said that it had confirmed antiviral effects against Covid-19.

Il-Yang Pharmaceutical and its Russian partner tried to repurpose the leukemia drug as Covid-19 treatment and conducted phase 3 clinical trials in Russia in May last year.

Many pharmaceutical companies developing Covid-19 treatment have chosen to repurpose existing drugs with an already secured safety profile as it could significantly shorten the time required for releasing the drug.

R-Pharm conducted the phase 3 study at 29 clinical institutions with 180 participants.

In 2020, Il-Yang Pharmaceutical said that Supect reduced the Covid-19 virus by 70 percent in 48 hours compared to the control group in a study performed with the virus strain provided by the Ministry of Food and Drug Safety.

“Although R-Pharm conducted the phase 3 trials of Radotinib as Covid-19 treatment, it noticed that the drug did not demonstrate better efficacy than the standard treatment recommended by Russian health authorities,” an official at Il-Yang Pharmaceutical said. “R-Pharm disclosed that it would not aim to win marketing approval of Radotinib for treating Covid-19 patients in Russia.”

The Korean company said its Russian partner plans to complete the registration within this year to expand the indication of Radotinib to treat CML.