By John Schwartz
Washington Post Staff Writer
Thursday, May 14, 1998; Page A12

An eagerly awaited diet drug could be approved by the Food and Drug Administration if its maker provides more information about the drug's safety and other issues, the manufacturer said yesterday.

Hoffmann-La Roche said the FDA had sent the company a letter that its obesity treatment, orlistat, could be approved if the company supplies further information addressing concerns that the drug may increase the risk for breast cancer.

Meanwhile, two other companies, Cephalon Inc. and Chiron Corp., said they had received similar notification from the agency about another drug, Myotrophin, a controversial treatment for amyotrophic lateral sclerosis (ALS), the degenerative neurological disorder more commonly known as Lou Gehrig's disease.

All three companies said they had received an "approvable letter," which lays out conditions that must be fulfilled before a new drug can be approved. Those conditions often involve performing more research to assuage worries over possible side effects, or showing more proof that the company can manufacture a drug properly. In most cases, however, the conditions can be fulfilled, and often within a year.

The FDA, which generally refuses to comment on approvable letters, declined to discuss either drug yesterday.

Both drugs have been held out as promising treatments, but both have had troubled histories.

The Hoffman-LaRoche drug, if approved, would be distributed under the brand name Xenical. It is the first of a new class of diet drugs called lipase inhibitors, which block the absorption of fat within the gastrointestinal tract.

Xenical was seen as a strong potential replacement for the diet drug combination known as Fen-phen, which was linked to heart valve damage. In studies, nearly three times as many patients lost 10 percent or more of body weight when they took Xenical and dieted compared to those who only dieted.

About 58 million Americans suffer from obesity, which has been linked to diabetes, high blood pressure, gallbladder disease and other ailments, and costs Americans an estimated $70 billion each year in medical treatment and lost productivity.

An FDA advisory committee unanimously recommended in 1997 that Xenical be approved. But a subsequent examination of clinical trials showed a slight rise in the incidence of breast cancer among women taking the drug. In a study involving 1,642 women, 12 women who received the drug developed breast cancer while only three women who received fake pills developed the disease.

When that data came out, the FDA called a second advisory panel meeting to reevaluate the drug. At the special advisory panel meeting last March, the company presented evidence that almost all of the breast cancer cases existed before the trial began. The panel split 5-5 over whether to recommend approving the drug.

The company yesterday said that it had been asked by the FDA to supply more information about breast cancer risks, and the agency and company met yesterday to discuss whether providing that information would require entirely new clinical trials or if the company could simply submit more thorough analysis of its data. The company said that it expects approval for the drug in early 1999.

"Roche is pleased with the FDA's decision and regards this as an important milestone in reaching final approval in the U.S.," the company said in a statement.

The ALS drug, Myotrophin, suffered a blow last year when an FDA advisory panel recommended against approving the drug because members of the panel believed that the companies had not proved the drug was effective against the fatal disease, which afflicts from 15,000 to 30,000 Americans. The drug has been available to many patients pending approval under FDA expanded-access programs.

The two companies that make Myotrophin, Cephalon Inc. and Chiron Corp., released a joint statement that said: "We plan to meet with the FDA to clarify the conditions for approval and to determine if these conditions can be satisfied." Cephalon spokesman Jason Rubin said that his company could make no prediction about when or if the FDA's conditions could be met. "We just don't know . . . we're trying to schedule a meeting with the FDA as soon as possible."

"We're obviously disappointed," said Carol Levey, vice president of marketing for the ALS Association, an industry and patient group. "ALS patients do not have time on their side . . . To them an FDA decision sooner is better than later."