Pardes Biosciences, Inc. reported commencement of a Phase 2 double-blind, randomized study to evaluate the antiviral activity, safety, and efficacy of orally administered PBI-0451 compared with placebo in non-hospitalized symptomatic adults with COVID-19 who are not at increased risk of progressing to severe illness. Pardes Biosciences expects to enroll 210 patients in the Phase 2 clinical trial at approximately 75 sites within the United States. Study eligibility will include symptoms of COVID-19 for 5 or less days and a positive test for SARS-CoV-2 infection.

Use of concomitant medications for underlying health conditions will not be restricted in the clinical trial. Participants will be administered PBI-0451 orally with food, twice daily, at a 700 mg (2x 350 mg tablets) dose or placebo over five days. The primary objective will be to determine the proportion of patients below the limit of detection in nasal swab samples for infectious SARS-CoV-2 on day three.

Secondary objectives will include assessments of safety and tolerability, time to sustained clinical recovery through day 28 defined as key COVID-19 symptoms, and hospitalizations and deaths. In a Phase 1 clinical trial, PBI-0451 at single and multiple doses demonstrated favorable tolerability without any study drug discontinuations and there were no treatment emergent drug-related adverse events assessed as greater than mild in severity. Additionally, no direct drug-related adverse findings were observed in 14-day or 28-day toxicology studies conducted across multiple preclinical species.

PBI-0451 does not require ritonavir boosting and has the potential to be used broadly due to a favorable drug-drug interaction profile.