Eiger BioPharmaceuticals announces publication of TOGETHER study data in NEJM

Eiger BioPharmaceuticals announced the publication of data from the investigator-sponsored Phase 3 TOGETHER study in patients with COVID-19 in the New England Journal of Medicine, or NEJM. The study, which evaluated newly diagnosed outpatients with mild-to-moderate COVID-19, found that among predominantly vaccinated participants with COVID-19, a single-dose treatment with Eiger’s investigational agent, peginterferon lambda, resulted in significantly decreased clinical events. The manuscript titled "Effect of Early Treatment with Pegylated Interferon Lambda among COVID-19 Patients" will be published in the February 9, 2023 issue of NEJM and follows the topline safety and efficacy data announced. The company said, "The primary endpoint was a composite endpoint of COVID-19-related hospitalization or emergency room visits greater than six hours. Secondary endpoints included SARS-CoV-2 viral clearance, all-cause hospitalization, mortality due to COVID-19, days in hospital and on ventilator, and adverse events. In the study, 931 patients received peginterferon lambda and 1018 received placebo. This was among the first trials to include a predominantly vaccinated population with 84% of the population having received vaccination prior to study entry. The study period included emergence of multiple COVID-19 variants of concern. The publication detailed results, highlighting a 51% reduction in COVID-19-related hospitalizations or emergency room visits greater than six hours (the primary outcome) for participants receiving peginterferon lambda vs. placebo, with 2.7% (25 of 931) of participants randomized to peginterferon lambda experiencing a primary outcome event, compared with 5.6% (57 of 1018) (relative risk 0.49, 95% Bayesian credible interval 0.30-0.76, posterior probability greater than99.9%) among patients randomized to placebo. This effect was maintained in subgroup analyses including COVID-19-related hospitalization alone (relative risk 0.57, 95% Bayesian credible intervals 0.33-0.95) and COVID-19-related hospitalization or death (hazard ratio 0.59, 95% Bayesian credible interval 0.35-0.97). The effects were consistent across dominant variants and vaccination status. Among individuals with a high viral level at baseline, peginterferon lambda resulted in lower viral loads and a higher percentage of patients clearing SARS-COV-2 RNA by Day 7, compared to placebo. The incidence of adverse events was similar in the two groups. Primary events in the study happened a median of 5 days (interquartile range 3 to 7 days) after randomization. The treatment effect for peginterferon lambda was more pronounced in patients who were treated within 3 days of symptom onset. Peginterferon lambda was consistent in the direction of effect on all secondary outcomes. Risk of COVID-19 hospitalization or all-cause death was reduced by 47% (hazard ratio, 0.53, 95% Bayesian credible interval 0.31 to 0.91) in participants receiving peginterferon lambda. In patients receiving treatment within 3 days of symptom onset, greater treatment effects were observed in the peginterferon lambda group, including 65% reduction of COVID-19 related hospitalization (hazard ratio 0.35, 95% Bayesian credible interval 0.15 -0.75), 81% risk reduction in all-cause death (relative risk 0.19 [0/567 vs 3/590], 95% Bayesian credible interval 0.01-1.57) and 89% risk reduction among unvaccinated patients (hazard ratio, 0.11; 95% Bayesian credible interval, 0.01 to 0.83). There was one COVID-19-related death in the peginterferon lambda group and four in the placebo group. Incidence of any treatment emergent adverse events was similar between peginterferon lambda and placebo groups, which were primarily injection site reactions."