Peginterferon-lambda for the treatment of COVID-19 in outpatients (2020)

Summary Background There are currently no effective treatments for outpatients with coronavirus disease 2019 (COVID-19). Interferon-lambda-1 is a Type III interferon involved in the innate antiviral response with activity against respiratory pathogens. Methods In this double-blind, placebo-controlled trial, outpatients with laboratory-confirmed COVID-19 were randomized to a single subcutaneous injection of peginterferon-lambda 180μg or placebo within 7 days of symptom onset or first positive swab if asymptomatic. The primary endpoint was proportion negative for SARS-CoV-2 RNA on Day 7 post-injection. Findings There were 30 patients per arm, with median baseline SARS-CoV-2 viral load of 6.71 (IQR 1.3-8.0) log copies/mL. The decline in SARS-CoV-2 RNA was greater in those treated with peginterferon-lambda than placebo (p=0.04). On Day 7, 24 participants (80%) in the peginterferon-lambda group had an undetectable viral load compared to 19 (63%) in the placebo arm (p=0.15). After controlling for baseline viral load, peginterferon lambda treatment resulted in a 4.12-fold (95CI 1.15-16.7, p=0.029) higher likelihood of viral clearance by Day 7. Of those with baseline viral load above 10E6 copies/mL, 15/19 (79%) in the peginterferon-lambda group were undetectable on Day 7 compared to 6/16 (38%) in the placebo group (p=0.012). Adverse events were similar between groups with only mild reversible transaminase elevations more frequently observed in the peginterferon-lambda group. Interpretation Peginterferon-lambda accelerated viral decline in outpatients with COVID-19 resulting in a greater proportion with viral clearance by Day 7, particularly in those with high baseline viral load. Peginterferon-lambda may have potential to prevent clinical deterioration and shorten duration of viral shedding. ( NCT04354259 ) Funding This study was supported by the Toronto COVID-19 Action Initiative, University of Toronto and the Ontario First COVID-19 Rapid Research Fund. Medication was supplied by Eiger BioPharma. Research in Context Treatment trials for COVID-19 have largely focused on hospitalized patients and no treatments are approved for people with mild to moderate disease in the outpatient setting. A number of studies in ambulatory populations have been registered but no controlled studies in the outpatient setting have been reported to date (Pubmed Search October 20, 2020, COVID-19 treatment; controlled trials). Uncontrolled case series of hydroxychloroquine with or without azithromycin have been reported with mixed results but no clear signal of efficacy and some concerns raised about cardiac toxicity. Treamtent in the outpatient setting has potential to prevent infected individuals from deteriorating and perhaps more importantly, may shorten the duration of viral shedding, reducing the risk of transmission and the duration required for self-isolation, with significant public health and societal impact. Added value of this study This is the first study to show an antiviral effect in outpatients with COVID-19. After controlling for baseline viral load, those treated with peginterferon-lambda had a 4.12-fold (95%CI 1.15-16.7, p=0.029) higher odds of viral clearance by Day 7 compared to those who received placebo. The viral load decline was faster with pegterferon-lambda and the effect was most pronounced in those with high viral loads. In individuals with a baseline viral load of 10E6 copies/mL or higher, 15/19 (79%) in the peginterferon-lambda arm cleared by Day 7 compared to 6/16 (38%) (p=0.012) in the placebo arm (OR 6.25, 95%CI 1.49-31.1, p=0.012), translating to a median time to viral clearance of 7 days (95%CI 6.2-7.8 days) with peginterferon-lambda compared to 10 days (95%CI 7.8-12.2 days) with placebo (p=0.038). Those with low viral loads (&lt;10E6 copies/mL) cleared quickly in both groups. Peginterferon-lambda was well-tolerated with a similar side effect profile to placebo and no concerning laboratory adverse events. Implications of all available evidence There is no currently approved therapy for outpatients with COVID-19. This study showed that peginterferon-lambda accelerated viral clearance, particularly in those with high baseline viral loads, highlighting the importance of quantitative viral load testing in the evaluation of antiviral agents for COVID-19. Treatment early in the course of disease may prevent clinical deterioration and shorenting of the duration of viral shedding may have important public health impact by limiting transmission and reducing the duration required for self-isolation. Additional trials of peginterferon-lambda and other antiviral strategies in the outpatient setting are required.