Advertisement

Pill With Possibilities

Raloxifene, approved for osteoporosis treatment, may hold out hope for postmenopausal women. It may offer the benefits of estrogen without posing the risks, supporters say. But detractors say more study is needed.

March 23, 1998|SHARI ROAN | TIMES HEALTH WRITER

For postmenopausal women, the decision on whether to take hormone replacement therapy has become a bit more complicated with the advent of a "designer estrogen."

The new medication, raloxifene hydrochloride, was approved in December (under the brand name Evista) specifically for the prevention of osteoporosis. But its possible benefits go beyond the bones--and enhance the health of postmenopausal women in other ways. And that has created a fair bit of excitement--as well as concern.

Raloxifene is among a class of medications called Selective Estrogen Receptor Modulators (SERMs), which are chemicals designed to mimic estrogen when it's beneficial and block estrogen in tissues when it can do harm. Tamoxifen, a drug that has been used since the 1970s in breast cancer treatment, is the best-known SERM. But with the approval of raloxifene, which should be available in pharmacies, enthusiasm for SERMs has skyrocketed--as well as the debate.

Many researchers believe that SERMs carry the benefits of estrogen--such as increasing bone density and reducing some factors that cause heart disease--while avoiding estrogen's risks. Estrogen replacement therapy is known to increase the risk of uterine cancer and may slightly increase the chance of developing breast cancer.

However, others are not convinced that SERMs, such as raloxifene, are a true alternative to estrogen replacement therapy.

"People may be overly exuberant in a premature sort of way," says Dr. Gail Greendale, an associate professor of medicine at UCLA.

"There clearly is a market to try to find a drug that will do all the good things estrogen does but none of the bad. And on one set of assumptions, raloxifene does look good. But we have to be critical," says Trudy Bush, an epidemiologist at the University of Baltimore School of Medicine.

But there is no understating the need for treatments that counteract the rapid health declines most women experience postmenopausally.

*

Each option--estrogen therapy and raloxifene--appears to have benefits, drawbacks and unknowns. But much less is known about raloxifene at this point.

"Is this a drug that I should be rushing up to my doctor and say, 'Give me this drug'? Doctors do not know," says Dr. Debra R. Judelson, a Beverly Hills internist and immediate past president of the American Medical Women's Assn. "The drug has not percolated through the medical literature enough for physicians to have some confidence level and to know when to offer it."

The medication was approved by the Food and Drug Administration based on two years of study showing that it increased bone density in postmenopausal women. But studies have also shown that raloxifene decreased total cholesterol and low-density cholesterol (the so-called bad kind). Moreover, officials at Eli Lilly & Co. of Indianapolis, which makes Evista, say that the drug appears to have no effect on the breast and may even decrease the risk of breast cancer.

That comment, made at an FDA advisory committee hearing last year, created a stir because the outstanding question surrounding estrogen therapy is that it may increase breast cancer risk.

"That is the area that has raised the greatest interest and the greatest number of questions based on our data to date," says Dr. Will Dere, director of medical research at Lilly.

According to Dere, there are several indications that raloxifene may be safe for women with breast cancer or who are at high risk for the disease.

Animal studies have demonstrated that the drug blocks the harmful effects of estrogen on breast tissue. And, in a small study of women with advanced breast cancer, high doses of raloxifene appeared to halt the disease.

Moreover, two years of studies on healthy women taking raloxifene showed that this group had a 62% decrease in newly diagnosed cases of breast cancer compared with a similar group not taking the medication.

"The data through two years of evaluation should be viewed as enticing but preliminary," Dere says. "It's promising. It's something we need to continue to monitor."

*

Others agree that there isn't enough data on raloxifene to know what it does or doesn't do.

"It looks like raloxifene halts bone loss and does a little something for lipids--not as much as estrogen, but something. It appears to leave the uterus alone," Greendale says. "The key organ we don't know about yet is the breast. There is a great hope that raloxifene will be breast-sparing and will be a drug that is very useful for women who have had breast cancer or have a high risk."

But doctors need to see published data on raloxifene's effect on the breast, Greendale said. "We really need to know what this breast evidence is. That is the thing that raloxifene will hinge on."

Another question that doctors are eager to see answered concerns the effects of raloxifene on preventing fractures. So far, the drug has only been shown to increase bone density.

Advertisement
Los Angeles Times Articles
|
|
|