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Leflunomide for the Treatment of Severe COVID‐19 in Patients with a Concurrent Malignancy

Trial Status: administratively complete

This phase I/II trial investigates the best dose and effect of leflunomide (good or bad) in treating patients with COVID-19 and a past or present cancer. Leflunomide has been used since the 1990s as a treatment for rheumatoid arthritis. Laboratory experiments done with human cells infected with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), the virus causing COVID‐19, showed that leflunomide was able to reduce the ability of the virus to make copies of itself. The coronavirus uses ribonucleic acid (RNA), a very long molecule that contains genetic information that is like a blueprint for making more copies of itself. Leflunomide inhibits the formation of RNA. The information gained from this study may help researchers to learn whether leflunomide is safe for use in treating cancer patients with COVID‐19, and whether it is potentially effective against the disease.