July 24, 2007

FDA Panel OKs Osteoporosis Drug to Cut Breast Cancer Risk

But critics say Evista's heart risks outweigh its benefits

TUESDAY, July 24 (HealthDay News) -- Despite concerns over cardiovascular side effects, a U.S. Food and Drug Administration panel on Tuesday recommended the osteoporosis drug Evista (raloxifene) for use in preventing breast cancer in certain high-risk groups of older women.

In a vote of 8 to 6, the FDA's Oncologic Drugs Advisory Committee recommended approval of the drug for postmenopausal women with osteoporosis, and, in a 10 to 4 vote, it also recommended the drug for postmenopausal women at high risk for breast cancer.

While the FDA usually follows the recommendations of its expert panels, it is not obligated to do so.

Evista's approval would give women a valuable option in fighting breast cancer, one expert said.

"We've got a drug out there, tamoxifen, with its advantages and its possible flaws,'' panel member David Harrington, chairman of the biostatistics department at Dana-Farber Cancer Institute in Boston, told Bloomberg news service. "Women at high risk for breast cancer, it would be very nice to have a second option for them," he said.

However, not everyone agrees with the panel's recommendation.

"The reason that we are concerned and will continued to be concerned about it is the history of every drug that's ever been used to 'prevent breast cancer,' " explained Barbara Brenner, the executive director of Breast Cancer Action.

Brenner noted that even women who do take these drugs can get breast cancer.

"In addition, the number of women who are going to be exposed to a drug with very serious and potentially fatal side effects in the interest of reducing very small numbers of breast cancer is very frightening to us," Brenner said. "We would like to see this disease prevented but not at the risk to women's health," she said.

While Evista has been shown to reduce the risk of breast cancer among postmenopausal women with osteoporosis, and postmenopausal women at high risk for breast cancer, it also increases their risks for blood clots and stroke.

In the Raloxifene Use for The Heart (RUTH) trial -- which included more than 10,000 postmenopausal women -- researchers found that, compared with placebo, Evista had no significant effect on the risk of first-time coronary events.

At the same time, it reduced the risk of invasive breast cancer by 44 percent -- meaning about 1.2 fewer cases of cancer per 1,000 women treated with raloxifene per year.

However, while the study showed no significant difference in deaths from any cause, or total deaths from stroke, women in the raloxifene group did have a 55 percent increased risk of fatal stroke (0.7 excess fatal strokes per 1,000 women treated per year) and a 44 percent increased risk of blood clots (1.2 more cases per women treated per year), according to a report published last July in the New England Journal of Medicine.

"We fail to understand why any woman in her right mind would want to expose herself to such risks," Brenner said. "If the drug is approved by the FDA, Eli Lilly & Co. [the maker of Evista] will heavily promote the drug, and many women will be made sick by in the interest of preventing breast cancer that will be in nobody's interest," she said.

Women should learn what this drug can and cannot do for them and make an informed choice, Brenner said. "Do not depend on the FDA to do that for you."

However, another expert backed the FDA panel's recommendation.

"The drug has been demonstrated to have benefit in preventing breast cancer in women at increased risk," said Dr. Len Lichtenfeld, the deputy chief medical officer at the American Cancer Society. "The drug should be approved. That would then give us two options, and Evista may have a better safety profile than tamoxifen," he said.

In the STAR (Study of Tamoxifen and Raloxifene) trial published last June, almost 20,000 postmenopausal women at increased risk for breast cancer took either tamoxifen or Evista daily for five years. Tamoxifen is the only drug approved for reducing breast cancer risk.

That trial found that both drugs reduced the risk of breast cancer by about 50 percent -- from eight cases per 1,000 women per year to about four per 1,000 women per year.

However, Evista was not as effective in preventing non-invasive breast cancers as tamoxifen, according to a report, which appeared in the Journal of the American Medical Association.

But the debate over Evista's fate goes on.

"We feel that the drug should not be approved, because it's an approach that's going expose healthy women to increased risks for one disease [heart trouble] to protect them from another," said Amy Allina, a program director at the National Women's Health Network.

"Even women at very high risk for breast cancer are taking on other risks with this drug," Allina said. "If they are not at very high risk of breast cancer, they are probably getting more harm than help," she said.

But Lichtenfeld contends that Evista has been long used by doctors in the treatment of osteoporosis, so physicians will be more comfortable in prescribing it to women to help prevent breast cancer. "Doctors are not talking to women about breast cancer prevention, and it's an area where more attention needs to be paid," the cancer society expert said.

"Both Evista and tamoxifen have risks," Lichtenfeld acknowledged. "But Evista has been used widely for the treatment of osteoporosis, so physicians are comfortable with that. While this is not a perfect answer to the increased risk of breast cancer, it is the best answer we have right now," he said.

The drug's maker was optimistic about the panel's decision. "Today is an especially good day for postmenopausal women," Gwen Krivi, vice president of Lilly Research Laboratories, said in a prepared statement. "If approved, Evista would be the first and only therapy available to address two leading health issues for postmenopausal women --osteoporosis and breast cancer. Following today's vote, our intention is to continue working with the FDA to make this important option a reality for patients."

Eli Lilly and Evista have a somewhat checkered past, however. In 2005, the company plead guilty and paid a $36 million fine for illegally promoting Evista to reduce the risk of breast cancer, a violation of the Food, Drug, and Cosmetic Act.

Source: www.nlm.nih.gov