Pardes Biosciences announced pomotrelvir failed to meet the primary endpoint for the treatment of mild-to-moderate symptomatic COVID-19 non-hospitalized, vaccinated adults

Pardes Biosciences announced top-line data that demonstrated pomotrelvir (PBI-0451, oral, main protease (Mpro) Inhibitor, 1400mg loading dose on Day 1; 700mg BID for 5 days) failed to meet the primary endpoint in its Ph2 trial for the treatment of mild-to-moderate symptomatic COVID-19 in non-hospitalized, vaccinated adults without risk factors for developing severe disease (i.e., standard-risk)

Key Details from the Pardes Press Release

Efficacy

• Pomotrelvir failed to meet the primary endpoint, measured by the proportion of participants below the limit of detection for infectious SARS-CoV-2 on day 3 of treatment with pomotrelvir vs. placebo 
  • On day 3, 70% of patients in the pomotrelvir-treated group reached undetectable SARS-CoV-2 levels compared to 63% in the placebo group (p=0.57); viral RNA level were also measured on Day 5 but were still not significantly different between the treatment and placebo groups.
  • Pomotrelvir did not demonstrate meaningful improvement over placebo in reduction from baseline of SARS-CoV-2 infectious virus titer by infectious virus assay, or in the reduction from baseline or proportion achieving undetectable viral load (RNA) by qRT-PCR measured from mid-turbinate swabs
• Comparable alleviation of COVID-19 symptoms was observed in the pomotrelvir and placebo groups
  • The median time to alleviation of the 14 U.S. FDA guidance-defined and 12 (excluding loss of taste and smell) targeted COVID-19 symptoms were 8 and 7 days, respectively, in both pomotrelvir and placebo treated participants
  • The median time to alleviation of all 5 key COVID-19 symptoms (cough, stuffy or runny nose, low energy or tiredness, sore throat, and feeling hot or feverish) was 6 days in both the pomotrelvir and placebo-treated groups (Note – these were the same symptoms evaluated in ensitrelvir’s Asian Ph2/3, SCORPIO-SR study)

Safety:

• There were no deaths and no participants experienced progression to severe COVID-19 in either arm of the study.
• Pomotrelvir was well tolerated, with treatment-emergent, drug-related nausea occurring in 3.1% of participants, which represented the only adverse event occurring in greater than 2% of pomotrelvir-treated participants. There were no drug-related AEs, SAEs, or AEs leading to discontinuation in either the pomotrelvir or placebo arms

Company strategy: Based on these results, Pardes will suspend further clinical development of pomotrelvir and explore a range of strategic alternatives, which may include an acquisition, merger, business combination or other undisclosed transactions.