As Coca-Cola once was to the American beverage industry, so is Premarin to national pharmaceutical production. Considered the gold standard of hormone-replacement therapies, Premarin is a name brand of estrogen that has been on the market for more than 50 years and is used to treat the discomforts of menopause. The most widely prescribed pill in the United States, its dominance has been reinforced by thousands of medical trials, including two national studies under way at the University of Miami School of Medicine.
The studies aim to discover whether Premarin provides additional benefits to aging women, such as the prevention of heart disease, osteoporosis, and cancer. But animal-rights activists argue that the hormone, which is manufactured from the urine of pregnant mares, causes unnecessary animal suffering. Further, they say, plant-derived and synthetically manufactured alternatives are available and might prove superior with additional research.
Premarin production begins with urine harvested from 49,000 pregnant mares that are confined to barns in Canada and North Dakota for six months out of every year. During their confinement, the horses are tethered full-time to rubber urine-collection bags. In the spring, they are turned out to pasture to give birth, after which they are reimpregnated to repeat the process. (The foals are sold -- some for recreational use, some for slaughter as horsemeat -- or, in the case of some females, raised to sexual maturity to become Premarin producers themselves.)
Animal-welfare activists first contacted People for the Ethical Treatment of Animals (PETA) in December 1993 complaining about the conditions in which the mares were kept. The stalls were allegedly so small that the horses could neither turn around nor lie down comfortably. Farmers were said to be restricting water intake in order to obtain more concentrated urine, and lack of proper exercise was reportedly leading to lameness in the horses. For the next two years, PETA sent undercover investigators to the farms.
"The stagnant air in the barn was sickening," one investigator wrote in a daily log of a January 1995 visit. "There were huge piles of manure behind each horse, obviously no one had cleaned in days. . . . None of the horses had any bedding at all. They were standing on bare concrete."
The log continues: "One of the horses was trying to kick her way out of the abrasive urine-collection device, the rubber tubing was twisted around her hind leg. . . . The pee bags were attached to the horse and the stall with such a short amount of tubing that the slightest movement by the mare will result in painful tension on her body. I can't help but think of the spent mares at the slaughter auctions last spring. They hobbled into the auction ring with raw, bloody sores from the pee bags which rubbed their skin raw."
Wyeth-Ayerst Laboratories, the Philadelphia--based company that manufactures Premarin, says PETA has been spreading "misinformation" about its product. In a seven-page press release countering the group's accusations, the company states, "The extremist charges about the care of the horses are inaccurate and do not properly recognize the substantial efforts undertaken by the company and the PMU [Pregnant Mare Urine] ranchers to care for the horses."
The release highlights Wyeth-Ayerst's "Recommended Code of Practice," which outlines standards for water, exercise, stall size, and nutrition. It also cites a report written by inspectors from the U.S. Department of Agriculture that concluded, "The allegations of abuse and inhumane treatment were unfounded. . . . In general we found the horses were receiving good to excellent care. Some farms were better than others, but none of them was a poor-quality operation."
PETA activists are not dissuaded. On the contrary, they say, the details of the USDA report bolster their claims. They point, for example, to a section that cites infections that go untreated because the necessary medication would make a mare's urine unusable: "We suspect that some producers may be failing to give parenteral antibiotics when needed, to avoid dumping the urine."
Wyeth-Ayerst has allowed other organizations to inspect the farms, including the Canadian Farm Animal Care Trust (CANFACT), the Royal Society for the Prevention of Cruelty to Animals, and the World Society for the Protection of Animals. The company has begun requiring six-week examinations of each farm by an independent veterinarian, and monthly visits by company inspectors. Farmers are encouraged to increase the value of the Premarin offspring through improved breeding so that fewer foals will be sent to slaughter.
The efforts have provoked varying reactions. The current issue of the quarterly magazine of the Humane Society of the United States takes Wyeth-Ayerst to task, pointing out that better treatment of the mares depends on company enforcement: "While we applaud any effort to improve life for the PMU mares, we believe that Wyeth-Ayerst has not done enough."
In contrast, the Canadian animal-welfare group CANFACT recently commended Wyeth-Ayerst for having made "a serious and conscientious effort" to address complaints about conditions on the farms.
A total of 164,000 women between the ages of 50 and 79 are expected to participate in the National Institutes of Health's $628 million Women's Health Initiative -- the largest study of its kind ever undertaken in the United States, involving 40 clinical centers nationwide. As part of the fifteen-year study, 3600 local women will be recruited. Wyeth-Ayerst agreed to provide more than 100 million Premarin tablets free of charge, a donation worth millions of dollars.
"What the government has here is a cooked deal with a huge pharmaceutical company," fumes Mary Beth Sweetland, director of research, investigation, and rescue for PETA. "The taxpayers are paying for a clinical trial that can only benefit one company."
According to doctors familiar with various estrogen-replacement therapies, Premarin costs about the same as the other drugs. The primary difference lies in the types of estrogen a drug provides. Plant-derived or synthetic forms of estrogen more closely mimic the hormone produced by the human body. But that, doctors emphasize, does not mean such forms present any advantage. Prescribing one form of estrogen over another "comes down to side effects," says Dr. Arthur Shapiro, a reproductive endocrinologist at the University of Miami. "It's a matter of suiting the patient."
Sweetland contends that the problem with using Premarin for the long-term study is that researchers will have no way of knowing whether their results are due to properties unique to horse estrogen. "At the end of fifteen years, we'll still be left wondering if other estrogen-replacement technologies have the same capabilities," she insists.
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Through a publicity blitz, PETA is attempting to persuade women to drop out of the WHI study unless the government switches to other estrogen-replacement drugs. The group spreads its message by leafletting at local horse shows and conducting symbolic yam dumps in front of clinic sites. (Yams are a source of plant-derived estrogen.) The University of Miami was treated to a free load of tubers in May.
Sweetland says thousands of women have responded to PETA's campaign. "We have received a lot of calls from Florida and Arizona and California, from women who had no idea that they were taking a pill made out of mares' urine and they had no idea of the suffering involved in that process," the PETA activist reports.
University of Miami employees working on the study referred all questions about PETA's campaign to the National Institutes of Health, where Dr. Jacques Rossouw is the lead project officer on the Women's Health Initiative study. Rossouw says he doubts the allegations of abuse, and explains that the NIH chose Premarin for the project because of the drug's widespread use. "Our feeling is that we owe it to the women of this country to test the drug that is most commonly prescribed, rather than another drug," he emphasizes.
"We have seen no indication that PETA has had any effect whatsoever on the study," adds Rossouw. "I don't think they have a lot of support for their campaign.