While the number of morbidly obese patients opting for bariatric surgery has risen over the past few years, a new research report suggests that this trend may not continue following regulatory approval of Sanofi's highly anticipated weight-loss drug Acomplia (rimonabant).

"The anti-obesity market is awaiting the arrival of rimonabant, a potential blockbuster that may postpone the need for bariatric surgeries, particularly in class II obese patients who would otherwise be eligible for surgical intervention," according to the report from Decision Resources.

Acomplia's developer, Sanofi-Aventis, submitted the drug for regulatory approval to both the U.S. Food and Drug Administration and European regulators last year. The FDA has said it will not act on approval of Acomplia for weight-loss until as yet undisclosed conditions are met.

The research report, however, concludes that "this novel therapy will reduce the impact of bariatric surgeries on the obesity pharmaceutical market provided it meets expectations."

The researchers suggest that a key factor in the growth of the number of patients opting for bariatric surgery has been "the lack of long-term efficacy and the modest weight loss associated with currently marketed anti-obesity drugs -- particularly among morbidly obese patients."

"The number of bariatric surgeries is on the rise, fueled by the potential for significant weight loss and safer procedures," the researchers report. However, they conclude that the surgical approach to obesity will remain a third-line therapy "because of the invasive nature of the treatment and the lifestyle aspect of the disease.

"No improvements in surgical procedures are likely to position bariatric surgery as a replacement for lifestyle interventions and drug therapies," the researchers said.

The Decision Resources report concludes that "vast commercial opportunities exist for a more efficacious treatment for obesity" such as Acomplia.