Remdesivir, sold under the brand name Veklury, is a broad-spectrum antiviral medication developed by the biopharmaceutical company Gilead Sciences. It is administered via injection into a vein. During the COVID-19 pandemic, remdesivir was approved or authorized for emergency use to treat COVID‑19 in around 50 countries. Updated guidelines from the World Health Organization in November 2020 include a conditional recommendation against the use of remdesivir for the treatment of COVID-19.

Remdesivir was originally developed to treat hepatitis C, and was subsequently investigated for Ebola virus disease and Marburg virus infections before being studied as a post-infection treatment for COVID-19.

The most common side effect in healthy volunteers is raised blood levels of liver enzymes (a sign of liver problems). The most common side effect in people with COVID‑19 is nausea. Side effects may include liver inflammation and an infusion-related reaction with nausea, low blood pressure, and sweating.

Remdesivir is a prodrug that is intended to allow intracellular delivery of GS-441524 monophosphate and subsequent biotransformation into GS-441524 triphosphate, a ribonucleotide analogue inhibitor of viral RNA polymerase.

The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication.