In 1960 Kelsey was hired by the FDA in Washington, D.C… At that time, she “was one of only seven full-time and four young part-time physicians reviewing drugs” for the FDA. One of her first assignments at the FDA was to review application by Richardson Merrell for the drug thalidomide (under the tradename Kevadon) as a tranquilizer and painkiller with specific indications to prescribe the drug to pregnant women for morning sickness. Even though it had already been approved in Canada and over 20 European and African countries, she withheld approval for the drug and requested further studies. Despite pressure from thalidomide’s manufacturer, Kelsey persisted in requesting additional information to explain an English study that documented a nervous system side effect.
Kelsey’s insistence that the drug should be fully tested prior to approval was vindicated when the births of deformed infants in Europe were linked to thalidomide ingestion by their mothers during pregnancy. Researchers discovered that the thalidomide crossed the placental barrier and caused serious birth defects in infants. She was hailed on the front page of The Washington Post as a heroine for averting a similar tragedy in the US. Morton Mintz, author of The Washington Post article, said “[Kelsey] prevented … the birth of hundreds or indeed thousands of armless and legless children.”
After Morton Mintz broke the story in July 1962, there was a substantial public outcry. The Kefauver Harris Amendment was passed unanimously by Congress in October 1962 to strengthen drug regulation. Companies were required to demonstrate the effectiveness of new drugs, report adverse reactions to the FDA, and request consent from patients participating in clinical studies. The drug testing reforms required “stricter limits on the testing and distribution of new drugs” to avoid similar problems. The amendments also, for the first time, recognized that “effectiveness [should be] required to be established prior to marketing.”
As a result of her blocking American approval of thalidomide, Kelsey was awarded the President’s Award for Distinguished Federal Civilian Service by President John F. Kennedy, becoming the second woman to receive that award. British Pathé released a film of Kennedy acknowledging Kelsey in a speech. After receiving the award, Kelsey continued her work at the FDA. There she played a key role in shaping and enforcing the 1962 Amendments. She also became responsible for directing the surveillance of drug testing at the FDA. Kelsey retired from the FDA in 2005, at age 90, after 45 years of service. In 2010 the FDA named the Kelsey Award for her, to be awarded to an FDA employee.