In New York City, the American Museum of Natural History and the Metropolitan Museum of Art both said Wednesday they will stop accepting donations from the Sacklers—the billionaire family that owns Purdue Pharma, maker of OxyContin, the highly addictive drug at the center of the opioid epidemic. Other cultural institutions, including the Guggenheim and London’s Tate Modern museum, have also severed ties to the Sacklers.