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Vladimir (Zev) Zelenko (born 1973)^[1] is a Ukrainian-American family physician known for promoting a three drug cocktail of hydroxychloroquine, zinc sulphate and azithromycin as part of an experimental outpatient treatment for COVID-19 that he has promoted as the Zelenko Protocol.

On March 23, 2020, Zelenko published an open letter to U.S. president Donald Trump where he claimed to have successfully treated hundreds of his COVID-19 patients with a 5 day course of his Protocol. Zelenko’s treatment protocol quickly gained notoriety with several media figures and various Trump’s administration officials promoting it, including Rudy Giuliani, Sean Hannity, and White House chief of staff Mark Meadows, despite cautionary messages from health experts.^[2]