Between 1976 and 1985, 52%of 198 new drugs that had been tested primarily on animals, had “serious post-approval risks”. These risks were defined as reactions that could lead to hospitalization, disability, or death. As a result, these drugs had to be withdrawn or completely relabeled. Naturally, this would make it impossible to estimate how many potentially useful drugs may have been needlessly abandoned because animal tests falsely suggested inefficacy or toxicity.*
The drug milrinone, which raises cardiac output, increased the survival of rats with artificially induced heart failure; humans with severe chronic heart failure had a 30%increase in mortality after taking this drug.* (source: Scientific American, Feb.97) The anti-viral drug fialuridine seemed safe in animals, however it caused liver failure in 7 of 15 humans taking it (5 died, 2 received liver transplants). The once-common painkiller zomepirac sodium was implicated in 14 deaths and hundreds of near-fatal allergic reactions. Anti-depressant, nomifensine, showed little toxicity in lab animals, yet caused severe liver toxicity and anemia in humans. All drugs were withdrawn from the market soon after their release.* (source: Scientific American, Feb. 97)
In all cases, money, time, and character was wasted. Millions of animals had their lives stolen needlessly, and people died as a direct result of conclusions drawn from animal testing.