Pfizer Pauses Experimental Gene Therapy Trial After Boy’s ‘Sudden’ Death

Pfizer said it is working with regulators and the Data Monitoring Committee to learn more about the boy’s potential cause of death.

A man wearing facemask and shield walks past the Pfizer headquarters in New York City, on March 11, 2021. Kena Betancur/AFP/Getty Images

Pharmaceutical giant Pfizer Inc. has halted a study of an experimental gene therapy for muscular dystrophy after a child who received the treatment died due to cardiac arrest.

The New York City-headquartered drugmaker revealed the boy’s sudden death in a community letter shared by the nonprofit advocacy group Parent Project Muscular Dystrophy (PPMD).