DENVER, CO -- June 21, 2001 -- New research has demonstrated the effects of three different compounds -- growth hormone (GH), tissue selective estrogen and alendronate (Fosamax) -- in treating and preventing osteoporosis.
The new studies were presented in a press conference today at ENDO 2001, the 83rd Annual Meeting of The Endocrine Society, which is taking place in Denver, Colorado, June 20-23, 2001.
Dr. Peter Gillberg, a researcher at Uppsala University in Sweden, presented a two-year study on the effects of GH treatments in men between the ages of 27 and 62 with idiopathic osteoporosis. Researchers gave one group of men GH every day, while a second group received GH every two weeks. The study also had a one-year follow-up period. After three years, the men in both groups experienced an increase in bone mineral density (BMD) and bone mineral content (BMC).
"This is the first time that research has shown that long term growth hormone treatments in men with idiopathic osteoporosis can result in increased bone mineral density and increased bone mineral content," said Dr. Gillberg. Two separate studies presented at the press conference also demonstrated the effectiveness of weekly administrations of alendronate to treat bone loss in postmenopausal women.
One study, which was presented by Dr. Henry Bone, an endocrinologist and investigator at the Michigan Bone and Mineral Clinic, presented findings from a two-year clinical trial that was conducted by researchers at Merck Research Labs and several institutions around the country. The clinical trial that was designed to compare the efficacy of alendronate in three dosages and administration rates -- 70 mg once-weekly, 35 mg twice-weekly and 10 mg daily -- on 1258 postmenopausal women with osteoporosis, through measurements of bone mineral density.
"The results of our double-blind, multicenter study prove that once weekly administration of alendronate in a dosage of 70 mg is therapeutically equivalent to a once-daily dosage of 10 mg in women with postmenopausal osteoporosis," said Dr. Bone. "The study also proves that the 70 mg dosage is well tolerated."
In another alendronate study, researchers at the Robert Wood Johnson Medical Center sought to discover effectiveness of longer-term, infrequent administration of alendronate on postmenopausal bone loss. According to Dr. Wimalawansa, the Chief of Endocrinology at Robert Wood Johnson Medical Center and the lead investigator on the study, when taken once daily, Alendronate, an FDA-approved drug for osteoporosis, increases bone density and strength. However, adherence to this standard therapy is often poor due to difficulty in administration and some unpleasant upper gastrointestinal side effects.
Researchers gave one group of 89 patients a 60 mg dose of alendronate once a week for two years. After two years, these patients were given the choice of remaining on the same regimen for two more years or changing to a 40 mg, once weekly, dosage. A second group of patients received the standard dose of alendronate -- 10 mg per day -- for all four years. The subjects' bone mineral density (BMD) was measured at the beginning of the study and then annually during the four years.
Dr. Sunil Wimalawansa noted that both groups experienced significant increases in bone mass and decreases in bone turnover. Conversely, the patients in the once-a-week group had an 88 percent compliance record, compared with only 72 percent in the daily group. In addition, nearly twice as many patients in the daily group discontinued the therapy, when compared with the weekly group.
"We have demonstrated that while improving compliance and adverse effects, once-a-week administration of alendronate is a highly effective, safe and economical way to increase bone mass in patients with osteoporosis," said Dr. Wimalawansa. "This is the first study of this kind and we now have over four years of bone mass data on infrequent therapy with alendronate in comparison with the standard daily dose."
In the final study, Dr. Ginger Constantine, a researcher at Wyeth-Ayerst Laboratories, explained the results of a phase II clinical trial that tested the effects of TSE-424 -- a novel tissue selective estrogen -- on 360 postmenopausal women. The study established that in low doses, TSE-424 acts like an estrogen agonist on the human body.
"In our phase II research, low doses of TSE-424 caused reductions in markers of bone remodeling," said Dr. Ginger Constantine, an investigator with Wyeth-Ayerst Laboratories. "The Phase III clinical trials will explore change in bone mineral density and reduction of fracture incidence."
SOURCE: The Endocrine Society
