Before pharmacovigilance existed

In 1957, when Chemie Grünenthal launched thalidomide as a sedative in West Germany, there was no regulatory requirement to demonstrate drug safety through controlled clinical trials. There was no adverse event reporting system. There was no post-marketing surveillance infrastructure. Drugs were approved based on limited clinical experience and manufacturer assertions.

Thalidomide was marketed as remarkably safe — so safe it was recommended for pregnant women experiencing morning sickness. It was sold over the counter in Germany, the UK, Canada, Australia, and dozens of other countries. By 1960, it was one of the best-selling drugs in Europe.

The signal that changed everything

In late 1961, two physicians independently identified the connection between thalidomide and a previously rare birth defect called phocomelia — the absence or severe shortening of limbs. Widukind Lenz in Germany and William McBride in Australia both noticed clusters of phocomelia cases in regions where thalidomide was widely prescribed to pregnant women.

The drug was withdrawn from the German market in November 1961, but the damage was catastrophic. Estimates suggest over 10,000 children were born with thalidomide-related birth defects worldwide. Thousands more pregnancies ended in stillbirth or early neonatal death.

The FDA and Frances Kelsey

In the United States, FDA reviewer Frances Oldham Kelsey repeatedly refused to approve thalidomide for the American market. She found the manufacturer's safety data insufficient and was particularly concerned about reports of peripheral neuropathy. Her insistence on additional evidence — against significant industry pressure — prevented the drug from reaching widespread American distribution.

Kelsey's decision became a pivotal moment in regulatory history. President Kennedy awarded her the President's Award for Distinguished Federal Civilian Service in 1962, and her case became the political catalyst for the most significant drug regulation reform in American history.

The regulatory architecture that followed

The thalidomide disaster produced the modern drug regulatory framework within three years. The Kefauver-Harris Amendment to the Federal Food, Drug, and Cosmetic Act, signed in October 1962, required for the first time that manufacturers demonstrate both safety and efficacy through adequate and well-controlled clinical trials before a drug could be marketed.

In the United Kingdom, the government established the Committee on Safety of Drugs in 1963, which evolved into the Committee on Safety of Medicines and eventually the Medicines and Healthcare products Regulatory Agency. The Yellow Card spontaneous reporting scheme — still operational today — was created as a direct response to thalidomide.

The World Health Organization established its Programme for International Drug Monitoring in 1968, creating the global pharmacovigilance infrastructure that now connects over 170 national pharmacovigilance centres through the Uppsala Monitoring Centre.

The irony of thalidomide's return

In one of pharmacology's more remarkable chapters, thalidomide was approved by the FDA in 1998 for erythema nodosum leprosum and subsequently for multiple myeloma. It is now a cornerstone of myeloma treatment. But its approval came with the most restrictive distribution program in FDA history — the THALOMID REMS program requires pregnancy testing, contraception counseling, and restricted prescribing to prevent the teratogenic harm that defined its legacy.

The story of thalidomide is ultimately the story of why pharmacovigilance exists as a discipline. Every adverse event report filed, every periodic safety update submitted, every risk management plan designed operates within a regulatory architecture that was built because one drug, marketed without adequate safety evaluation, caused irreversible harm to thousands of children.