Sorrento Therapeutics releases Phase 1b data of OVYDSO

Sorrento Therapeutics released unblinded Phase 1b study data of its oral main viral protease inhibitor, OVYDSO in COVID patients. This Phase 1b safety, PK and efficacy study in healthy volunteers and COVID patients was conducted in China. The study is entitled: "A Randomized, Double-Blind, Placebo-Controlled, Phase I Study to Assess the Safety, Tolerability, Pharmacokinetics and Efficacy of Single and Multiple Oral Doses of STI-1558 in Healthy Volunteers and COVID Patients". In the SAD portion of the study, four dose-escalation cohorts were conducted with eight subjects in each cohort – randomized 3:1. In the MAD portion of the study, three dose-escalation cohorts with daily dose of 300 mg BID, 600 mg BID or 800 mg BID for consecutive 7.5 days were conducted with eight participants infected with SARS-CoV-2 in each dose cohort – randomized 3:1, and in the 600 mg BID dose cohort, an additional 16 participants infected with SARS-CoV-2 were added as a cohort extension. The topline safety, PK and efficacy data from the SAD and MAD portions of the study are now available. Overall, STI-1558 was well-tolerated at these doses, with most subjects in both the SAD and MAD portions of the study reporting no AEs. There was no dose limiting toxicity during the study. There were no severe or serious AEs, no premature discontinuations of STI-1558 due to an AE, and no deaths. Most AEs were mild, transient, unrelated and required no medical treatment. A total of 12 subjects reported an AE in the SAD portion of the study, with one AE of elevated blood thyroid-stimulating hormone deemed related to STI-1558 in the 2000 mg cohort. In the MAD portion of the study in COVID-19 patients, 20 subjects from a total of 46 subjects reported AEs, with only four subjects experiencing STI-1558-related events. Antiviral activity was evaluated in the MAD portion of the study in participants infected with SARS-CoV2. The viral RNA load in participants infected with SARS-CoV2 was measured by quantitative PCR. The viral RNA load was significantly reduced in COVID-19 patients treated with STI-1558 on Days 2, 4 and 6 post-treatment in comparison with placebo, indicating the strong antiviral activity of STI-1558 in COVID-19 patients. After communication with the regulatory agency, a Phase 3 protocol was submitted to China NMPA. The Phase 3 trial is entitled: "A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Phase III Study to Assess the Efficacy and Safety of STI-1558 for Treatment of Mild and Moderate Symptomatic Adults Infected with SARS-CoV-2". Once cleared by NMPA, the study, which plans to enroll 1200 COVID-19 patients, will be subsequently commenced.