Diet Drugs and the FDA

On Sept. 16, 2010, the 14-person Endocrinologic and Metabolic Drugs Advisory Committee recommended that the U.S. Food and Drug Administration (FDA) deny approval for Arena Pharmaceuticals to sell the weight loss drug lorcaserin in the United States.

Arena had intended to market lorcaserin under the trade name “Lorqess.” The manufacturer has said that the drug is designed to work as an appetite-suppressant.

Though the FDA is not bound to abide by the council’s decision, the agency is expected to reject the drug.

In a Sept. 16 article on the decision, Todd Zwillich of WebMD Health News described the vote as “the latest blow to the drug industry’s effort to develop safe and effective weight loss drugs.”

Prior to the vote, the FDA posted the following announcement on its website:

Modest weight loss and safety questions, including that of a possible link to valvular heart disease, will be at the forefront of today’s advisory committee discussion on whether to recommend approval of Arena’s lorcaserin.

Although the weight loss observed in the lorcaserin-treated patients generally improved their blood pressure, glucose and insulin levels, as well as levels of high sensitivity C-reactive protein, FDA reviewers expressed concerns about the drug’s safety and overall effect on weight loss

Concerns Related to Cancer

The day before the FDA advisory committee voted, a Wall Street Journal article by Alicia Mundy and Jennifer Corbett Dooren raised the following concerns about lorcaserin:

Arena says lorcaserin, which works on the patient’s central nervous system to damp appetite, helped nearly half of the patients in a study achieve at least 5% weight loss after a year.

The FDA staff analysis, released in advance of the advisory panel meeting, found that lorcaserin only met one efficacy standard by a “slim margin” and called the average weight loss “relatively low.”

More worrisome, the staff raised an unexpected concern about cancer, saying breast-cancer tumors were found in rats taking the drug, though not in humans.

On Sept. 17, Arena CEO Jack Lief told Toni Clarke of Reuters that the FDA advisory committee members “were having difficulty understanding the presentation,” and implied that an absence of experts in the study of potentially carcinogenic agents on the panel led to the recommendation that lorcaserin be rejected.

More Bad News for Diet Drug Manufacturers

Arena (and lorcaserin) weren’t the only manufacturer/drug combo to be on the receiving end of less-than-glowing remarks from the Endocrinologic and Metabolic Drugs Advisory Committee. A Sept. 16 article by Bruce Japsen and Shari Roan of Tribune Newspapers provided the following details about the panel’s reservations regarding the diet drug Meridia, which is produced by Abbott Laboratories:

In a rebuke of the Abbott Laboratories diet drug Meridia, eight of 16 members of a Food and Drug Administration advisory panel said Wednesday that the drug should be withdrawn from the U.S. market.

Six of the panelists said the drug should be prescribed only by “specially trained physicians.” The other two panelists said a new black box warning should be added to alert doctors to the increased risks of heart attacks and the need for closer monitoring of patients’ blood pressure, pulse and body weight.

None of the panelists on the Endocrinologic and Metabolic Drugs Advisory Committee said the drug should remain on the market in its current form, with labeling that says the drug is not intended for patients with a history of heart disease and other cardiovascular issues.

So even if the FDA decides to keep it on the market, doctors will be encouraged to prescribe it in limited circumstances.

The FDA advisory committee’s vote of no-confidence followed on the heels of a study in the New England Journal of Medicine, Japsen and Roan reported, in which Meridia use was associated with an increased likelihood of stroke, heart attack, cardiac arrest or cardiac death.