Once again, the Women's Health Initiative appears likely to provide fodder for many lawyers who drag Pfizer into court. Why? A new study links the Prempro hormone replacement treatment, which is already linked to a higher risk of breast cancer and heart disease, is now linked to a higher risk of death. And the publicity for this finding, which will be considerable, may finally put the cabash on Prempro sales.
The latest data, which was published in the Journal of the American Medical Association, followed 12,788 women since 2002, when the federally funded WHI study that compared HRT with placebos was halted. In the new findings, there were 678 cases of invasive breast cancer, including 385 for women taking hormones and 293 with a placebo. More women who took hormones died from breast cancer - 0.03 percent per year, versus 0.01 percent per year in the placebo group. That amounts to 2.6 deaths per 10,000 women per year versus 1.3 deaths in the placebo group (see the abstract).
After the WHI was released eight years ago, HRT use plummeted and led to a drop in breast cancer rates, with about 100,000 fewer invasive tumors detected from 2002 to 2007 than expected, said lead researcher Rowan Chlebowski, chief of medical oncology at the University of California, Los Angeles, School of Medicine, tells Bloomberg News. Using a 10-year mortality rate of about 20 percent, he calculates the reduction in hormone use may have prevented about 20,000 deaths.
The findings should cause doctors to cut back on long-term usage to treat hot flashes and night sweats. "I don’t think you can say that now,” Chlebowski tells the news service. “I know some people have to take it because they can’t function, but the message now is that you really should try to stop after a year or two...Women should think critically about if they need this, if their symptoms are significant and if they would persist.”
In an accompanying editorial in JAMA, Peter Bach, a physician at Memorial Sloan-Kettering Cancer Center, writes that, "given the substantial population of women who seek relief from menopausal symptoms and the large potential burden of disease that could be created if medications given to alleviate symptoms today cause cancer and other deaths tomorrow, it seems that additional randomized trials are needed specifically to determine whether lower doses or shorter durations of hormone therapy could alleviate menopausal symptoms without increasing cancer risk."
Ironically, the study was released on the same day that Pfizer won a lawsuit brought by an Arkansas woman who claimed Wyeth - which Pfizer bought last year - hid the link between Prempro and a higher risk of breast cancer. Out of 13 such cases, Pfizer has now won six, although another 8,000 or so are still pending. About 3,000, by the way, have been dismissed before reaching trial. Prempro and a related product, Premarin, generated some $2 billion before the WHI was released and generated $260 million in this year's second quarter.
A Pfzier spokesman writes to say that, "we stand behind the current, science-based guidance in Prempro’s label, which advises doctors to prescribe the medicine at the ‘lowest effective dose and for the shortest duration consistent with treatment goals and risks for the individual woman’ and patients to ‘talk regularly’ with their healthcare provider about whether treatment is still appropriate for them.”