Courts in Philadephia recently ruled in favor of two plaintiffs who sued Pfizer because they believed their breast cancer was caused by taking Prempro, an estrogen plus progestin combined hormone replacement therapy (formerly sold by Wyeth).
More than $100 million was awarded by juries between those two cases, although news reports indicate that Pfizer will appeal and damages awarded are likely to be reduced; a Pfizer spokesperson said the company does not believe the verdicts “were supported by the evidence or the law.” About 10,000 similar cases are apparently pending at this time.
In 2002, the Women’s Health Initiative study was released results indicating that women taking estrogen plus progestin hormone replacement (such as Prempro) were more likely to develop breast cancer than women taking placebo, and their cancers were more likely to be more advanced. The trial was stopped early that year after it became clear to investigators that the risks of combination hormone therapy outweighed the reported benefits.
As a result of WHI findings, in 2003 the FDA required the addition of a black box warning to the drug’s label to state that estrogen and estrogen plus progestin therapies should not be used for the prevention of cardiovascular disease, and to warn of increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis in postmenopausal women taking the estrogen/progestin combo.