NON-HORMONE DRUG FOR OSTEOPOROSIS WINS OK

Osteoporosis, the brittle bone disorder that affects about 20 million American women, can be treated for the first time with a non-hormone drug.

The Food and Drug Administration announced Monday that it was approving the marketing of alen-dronate, a hormone-free drug that can be used by women unable to tolerate estrogen. The drug also can be used to treat Paget's disease, another type of bone disorder.Studies of alendronate show it can stop the loss of bone density and allow the body to grow healthy bone.

"This approval is very important," said Sandra Raymond, a founding director of the National Osteoporosis Foundation. "This means that physicians and patients enter a new era with a broader array of treatment options for osteo-porosis."

Osteoporosis is a thinning and weakening of bone that strikes about a third of all women after menopause. The disorder hits about 25 million Americans, but 80 percent of the patients are women past the age of menopause, Raymond said.

Some 7 million to 8 million women with a severe form of the disease experience spontaneous frac-tures, usually of bones in the back. Broken hips, legs and arms also are common. About $10 billion is spent annually on the disease, mostly for treatment of fractures.

The most common treatment for women with the disorder has been estrogen hormone replacement therapy, but thousands of women have been unable to take the hormone because of various side effects.

Alendronate is the first in a class of drugs known as bisphos-pho-nates that work directly on bone without hormones.

Dr. Ethel Siris, director of osteoporosis programs at the Columbia-Presbyterian Medical Center in New York, said alendronate blocks the action of excess osteoclasts, cells whose job is to dissolve worn-out bone.

Normally, the bone removed by osteoclasts is quickly replaced by other cells, the osteoblasts. But in post-menopausal women, said Siris, "the osteoclasts go wild and resorb bone too rapidly." The result is brittle bone.

Siris said alendronate works by coating the surplus osteoclasts and suppressing their action.

A series of studies involving more than 1,800 women aged 41 to 85 showed that bone strength in the spine and hip was increased by about 8 percent in those taking alendronate. Patients in a comparison group taking a placebo had a decline in bone density of about 0.65 percent.