The National Institutes of Health (NIH) announced preliminary findings from the estrogen-alone study arm of the Women's Health Initiative (WHI), and its memory sub-study - WHIMS. Wyeth Pharmaceuticals, a division of Wyeth says the announcement provides valuable information for women and physicians about certain risks and benefits of estrogen. In Wyeth's view, the results from this prevention trial, when added to the current wealth of scientific evidence, reinforce the use of estrogen for its indications - the relief of moderate to severe vasomotor symptoms and vaginal atrophy, and the prevention of postmenopausal osteoporosis.
Based on preliminary findings from nearly seven years of study, the NIH has informed Wyeth that in the WHI Study, estrogen therapy:
* Decreased the risk of hip fracture;
* Did not increase the risk of breast cancer;
* Did not increase or decrease the overall risk or benefit of coronary heart disease (CHD); and
* Increased the risk of stroke, similar to the increase in risk previously reported from the estrogen plus progestin (E+P) study arm of WHI.
In the WHIMS sub-study of women age 65 and older, estrogen-alone was reported to show a trend toward an increase in probable dementia and mild cognitive impairment. It is important to note that the risk of cognitive decline increases dramatically with age and this study evaluated women who were, on average, 25 years older than the typical estrogen therapy user.
"A significant finding from the WHI is that estrogen therapy did not increase the risk of breast cancer. This finding is good news for many women who have had a hysterectomy and their physicians who want to prescribe estrogen to relieve moderate to severe menopausal symptoms," says Victoria Kusiak, vice president, Clinical Affairs and North American Medical Director at Wyeth Pharmaceuticals. "Furthermore, WHI provides valuable information for women who are at the point where they must consider estrogen for prevention of osteoporosis."
The WHI Study reports an association between estrogen use and an increased risk of stroke. This potential risk is reflected in the current product label for Wyeth's estrogen therapy products.
It is Wyeth's view that hormone therapy with estrogen alone or with estrogen plus progestin should be prescribed at the lowest dose for the shortest duration consistent with treatment goals and risks for the individual woman.
It should be noted that the 0.625 mg strength of Premarin (conjugated estrogens tablets, USP) was studied in the WHI; today, Wyeth has a number of lower dose estrogen and estrogen plus progestin options widely available.
The WHI did not evaluate estrogen for its primary uses: the relief of moderate to severe menopausal symptoms and the prevention of postmenopausal osteoporosis. Its efficacy for these uses is well supported in published scientific literature. The findings from the estrogen-alone arm of the WHI are a valuable addition to the clinical database for the Premarin Family of Products. The Premarin Family offers the most significant clinical experience and one of the largest safety databases available, providing women and their physicians the most current, comprehensive information upon which to base appropriate treatment decisions.
"The symptoms associated with menopause - such as hot flashes and night sweats - can be a major concern for women. These symptoms can disrupt a woman's daily activities at home or work, interrupt her sleep, contribute to fatigue and interfere with intimacy. It is estimated that 75 per cent of women will experience menopausal symptoms, making estrogen an important treatment option," says Dr. Kusiak.
When more complete data from WHI are available, Wyeth will assess what impact these findings have on its product labeling, and whether there are opportunities to enhance the product indications with respect to the prevention of osteoporosis and postmenopausal fracture, and/or to update labeling to reflect the breast cancer finding.
To help ensure that women and their doctors are making choices based on up-to-date science, Wyeth will continue to keep physicians informed of new information, like the preliminary findings released by the NIH today. Wyeth has established an 800 number for health care providers and is providing an online resource - (www.estrogeninfo.com) - where physicians and consumers can get more information on this announcement from a variety of authoritative sources.
Both Premarin and Prempro (conjugated estrogens/medroxy-progesterone acetate tablets) are widely available to women in lower doses than those studied in the WHI.
The WHI is a large-scale study sponsored by the National Institutes of Health. It was designed to evaluate hormone therapy, dietary modification, calcium, and vitamin D as preventative therapies for postmenopausal women. The hormone therapy arms were designed to assess selected long-term risks and benefits of Premarin and Prempro.
Wyeth provided the medications used in the hormone therapy portion of the WHI Study, but does not have a role in the analysis or reporting of study findings.
The primary efficacy endpoint was the prevention of coronary heart disease and the primary safety endpoint was the risk of breast cancer. The secondary endpoints included hip fracture, colorectal cancer, stroke, pulmonary embolism, and death from other causes. The estrogen plus progestin study arm concluded in July 2002.
Initially, researchers enrolled more than 10,700 women in the estrogen- alone study arm. Study participants have now been asked to discontinue their study medication and enter into the follow-up phase.
WHI researchers will now analyze the data from the active trial period of the estrogen-alone study arm and are expected to publish results on the risks and benefits of estrogen therapy in the coming months.
The NIH also commented on the results from the Women's Health Initiative Memory Study (WHIMS), a sub-study of the WHI. WHIMS was a Wyeth-funded study designed to evaluate memory in women age 65 and older who were taking estrogen or estrogen plus progestin therapy. In the E+P arm of the study, the investigators reported that there was an increased risk of probable dementia and mild cognitive impairment. According to the NIH, the data from the estrogen-alone arm of WHIMS show a trend towards an increased risk in probable dementia and mild cognitive impairment.