Knoll's Sibutramine Rejected By US Panel

Knoll Pharmaceuticals' New Drug Application for its antiobesity drug Meridia (sibutramine) has been rejected by a US Food and Drug Administration advisory committee, on the grounds that the drug is associated with too great a risk of elevated blood pressure. Knoll acquired the drug when it bought Boots' pharmaceutical business last year.

The committee voted 5-4 that the benefits of sibutramine do not outweigh its risks, although it agreed that the drug met the FDA's previously drawn-up criteria for weight loss. Sibutramine is a 5-HT/noradrenaline reuptake inhibitor, a new class of drug for the treatment of overweight.

In the first of two 12-month pivotal trials submitted in support of the NDA (BPI 852), 50% of patients on 10mg sibutramine per day (the optimum dose) experienced a 5% or greater loss in weight, compared to just 13% of placebo patients. In the other trial, called SB1047, the percentages were 39% and 20.4%, respectively.