FDA Panel Recommends Lap-Band for Lighter Patients
December 6, 2010 — A US Food and Drug Administration (FDA) advisory panel has voted 8 to 2 in favor of approving an expanded indication for an implantable adjustable gastric band (Lap-Band Adjustable Gastric Banding System; Allergan) to be used for weight reduction in patients with a body mass index (BMI) of at least 30 kg/m2 and less than 40 kg/m2.
The device is currently indicated for patients with severe obesity (BMI of at least 40 kg/m2 or BMI of at least 35 kg/m2 with 1 or more severe comorbid conditions) or for those who are at least 100 pounds heavier than their estimated ideal body weight.
"Patients with a BMI of less than 35 kg/m2 (even with a comorbid condition) are usually not considered appropriate for bariatric surgery," note the manufacturers in a report prepared for the FDA. "Expansion of the indication to include lower BMI patients would change the current practice of medicine with respect to bariatric surgery."
The Gastroenterology and Urology Devices Advisory Committee voted on the expanded indication on December 3.
In a study evaluating the Lap-Band for its original indication, approximately 20% of patients were able to lose at least 50% of their excess weight by 3 years, and 10% lost 75% of their excess weight.
In patients with a BMI of at least 30 kg/m2 and less than 40 kg/m2, a single-group, prospective study was conducted to evaluate the device. A total of 151 patients were enrolled at 7 investigational sites in the United States.
Subjects were primarily female and white, with a median age of 40 years and a mean baseline BMI of 35.4 kg/m2 (range, 29.8 - 39.9 kg/m2). Mean weight at surgery was 214.9 pounds (range, 152.6 - 286.2 pounds), and mean excess weight was 62.8 pounds (range, 28.8 - 100.7 pounds).
Almost 66% of all implanted participants lost at least 50% of their excess weight at 1 year. In addition, the primary efficacy endpoint — more than 40% of participants achieving at least 30% excess weight loss at 12 months — was achieved (P < .0001); 83.9% of the intent-to-treat evaluable patients (n = 143) and 80.5% of the intent-to-treat participants (n = 149) achieved this endpoint. The primary endpoint was met in 84.4% of the per protocol patients.
The mean percentage weight loss (total weight loss) was 18.3% (n = 143) at 12 months. Excess weight decreased from a mean of 62.8 pounds at baseline to 22.8 pounds at 12 months (n = 143).
During the 12-month period, 131 patients (87.9%) experienced a total of 524 adverse events. About one third of the adverse events were considered related to treatment. The majority of device-related adverse events were mild (n = 118; 54.9%); 2.3% were severe (5 events in 3 patients).
The most common device-related adverse events were vomiting in 20.0%, dysphagia in 15.3%, postprocedural pain in 13.0%, and gastroesophageal reflux disease in 10.2% of the patients. Reoperations were necessary in less than 5% of patients, and no deaths were reported.
The panel voted on 3 questions regarding the new indication: whether the data supported the efficacy of this device for the new indication, whether the data supported its safety, and whether the benefits appeared to outweigh the risks. The panel voted in favor of each question: 8 to 2 for the first question, 8 to 1 with 1 abstention for question 2, and 8 to 2 for question 3.
"Although the current study is small, I think that there's reasonable assurance...that this is an acceptable change," said Jon C. Gould, MD, from the University of Wisconsin School of Medicine and Public Health in Madison.
The committee expressed concerns about the time frame of the study, suggesting that more long-term data are needed to adequately assess the efficacy and safety and that a registry could be set up to collect data on long-term outcomes.
According to the manufacturers, effectiveness of the Lap-Band for "the treatment of severe obesity with respect to long-term weight loss is less than that of other bariatric surgical procedures, but substantially better than traditional behavioral or medical therapy."
The Lap-Band was first approved for weight reduction in the morbidly obese on June 5, 2001. The device is intended to induce weight loss in obese patients by limiting food consumption.