Pardes Biosciences, Inc. reported topline results from its Phase 2 clinical trial evaluating pomotrelvir for the treatment of mild-to-moderate COVID-19 in test-positive, symptomatic, otherwise healthy, vaccinated adults without risk factors for developing severe disease. Pomotrelvir did not 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 versus placebo. Otherwise healthy, vaccinated adults without risk factors for progression to severe disease experienced rapid clearance of SARS-CoV-2 virus and evidence of rapid alleviation of targeted and key COVID-19 symptoms independent of treatment arm.

As a result of these data, the Company has decided to suspend further development of pomotrelvir and explore a range of strategic alternatives. Topline Phase 2 Results: Pomotrelvir did not achieve the primary endpoint as measured by proportion of participants below the limit of detection for infectious SARS-CoV-2 on day 3 by infectious virus assay (IVA) with 70% reaching undetectable levels in the pomotrelvir treated group versus 63% in the placebo group (p=0.57). Pomotrelvir did not demonstrate meaningful improvement over placebo in reduction from baseline of SARS-CoV-2 infectious virus titer by IVA or in the reduction from baseline or proportion achieving undetectable viral load (RNA) by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) measured from mid-turbinate swabs.

There were no deaths and no participants experienced progression to severe COVID-19. There were no drug-related adverse events, serious adverse events, or adverse events leading to discontinuation in either treatment arm. 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.

The median time to alleviation of the 14 U.S. Food and Drug Administration 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. Five predefined key COVID-19 symptoms of cough, stuffy or runny nose, low energy or tiredness, sore throat, and feeling hot or feverish were reported within a range of prevalence of 89% to 60% of participants at baseline. The median time to alleviation of all of these 5 key COVID-19 symptoms was 6 days in both pomotrelvir and placebo treated participants; median times to resolution of each individual key symptom ranged between 2 and 5 days, and were similar for both pomotrelvir and placebo treated participants.

Overall, baseline levels of SARS-CoV-2 infectious virus and viral load were lower, clearance of infectious virus was more rapid, and the speed of COVID-19 symptom improvement was faster than anticipated when the study was designed. These are important considerations when exploring the clinical benefit for potential SARS-CoV-2 therapeutics at this stage of the COVID-19 pandemic, with high levels of underlying population immunity due to vaccination plus ongoing community exposure to SARS-CoV-2 variants resulting in the likelihood of more modest viral burden and acute symptoms. This study was conducted in otherwise healthy, vaccinated adults without risk factors for progression to severe disease with = 2 symptoms consistent with COVID-19 for = 5 days and with a positive SARS-CoV-2 test (qRT-PCR or RAT) within 24 hours of randomization. The majority (83%) of enrolled participants were randomized to treatment within 3 days of COVID-19 symptom onset.

Participants received study drug treatment as soon as possible upon randomization and were instructed to take the full 1400 mg total daily dose of study drug on study day 1, followed by 700 mg twice-daily, approximately every 12 hours, administered with food, for a total of 5 days (10 doses). The Company continues to analyze the results from this study and intends to submit these data to a scientific conference and/or peer-reviewed publication to contribute to the understanding of SARS-CoV-2 and the development of potential COVID-19 therapeutics. Based on these results, the Company will suspend further clinical development of pomotrelvir and the Company's Board of Directors has initiated a review of a range of strategic alternatives that may include, but are not limited to, an acquisition, merger, business combination, or other transaction.

There can be no assurance that this review process will result in the Company pursuing a transaction or that any transaction, if pursued, will be completed on attractive terms or at all. The Company does not intend to comment further unless or until the Board of Directors has approved a definitive course of action, the review process is concluded, or it is determined that other disclosure is appropriate. As of March 31, 2023, the Company's preliminary cash, cash equivalents and short-term investments totaled approximately $172.4 million.