Interferon lambda as a potential treatment for COVID-19

INTRODUCTION: Pegylated interferon lambda substantially reduced the risk of COVID-19-related hospitalizations or emergency room visits in a recent phase 3, multi-center, randomized, double-blind, placebo-controlled study of high-risk, non-hospitalized adult patients with SARS-CoV-2 infection compared to treatment with placebo. AREAS COVERED: Interferons are a family of signaling molecules produced as part of the innate immune response to viral infections. The administration of exogenous interferon may limit disease progression in patients with COVID-19. EXPERT OPINION: Interferons have been used to treat viral infections, including hepatitis B and hepatitis C, and malignancies such as non-Hodgkin's lymphoma, as well as the autoimmune condition multiple sclerosis. This manuscript examines what is known about the role of interferon lambda in the treatment of COVID-19, including potential limitations, and explores how this approach may be used in the future.