FDA. US: The U.S. Food and Drug Administration today approved the Maestro
Rechargeable System for certain obese adults, the first weight loss
treatment device that targets the nerve pathway between the brain and
the stomach that controls feelings of hunger and fullness.
The
Maestro Rechargeable System, the first FDA-approved obesity device since
2007, is approved to treat patients aged 18 and older who have not been
able to lose weight with a weight loss program, and who have a body
mass index of 35 to 45 with at least one other obesity-related
condition, such as type 2 diabetes.
BMI, which measures body fat
based on an individual’s weight and height, is used to define the
obesity categories. According to the Centers for Disease Control and
Prevention, more than one-third of all U.S. adults are obese, and people
with obesity are at increased risk of heart disease, stroke, type 2
diabetes and certain kinds of cancer.
“Obesity and its related medical conditions are major public health problems,” said William
Maisel, M.D., M.P.H., deputy director for science and chief scientist
in the FDA’s Center for Devices and Radiological Health. “Medical
devices can help physicians and patients to develop comprehensive
obesity treatment plans.”
The Maestro Rechargeable System
consists of a rechargeable electrical pulse generator, wire leads and
electrodes implanted surgically into the abdomen. It works by sending
intermittent electrical pulses to the trunks in the abdominal vagus
nerve, which is involved in regulating stomach emptying and signaling to
the brain that the stomach feels empty or full. Although it is known
that the electric stimulation blocks nerve activity between the brain
and the stomach, the specific mechanisms for weight loss due to use of
the device are unknown.
External controllers allow the patient to
charge the device and allow health care professionals to adjust the
device’s settings in order to provide optimal therapy with minimal side
effects.
The safety and effectiveness of the Maestro Rechargeable
System were evaluated in a clinical trial that included 233 patients
with a BMI of 35 or greater. The weight loss and adverse events of 157
patients who received the active Maestro device (the experimental group)
were compared to 76 patients in the control group who received a
Maestro electrical pulse generator that was not activated. The study
found that after 12 months, the experimental group lost 8.5 percent more
of its excess weight than the control group. About half (52.5 percent)
of the patients in the experimental group lost at least 20 percent of
their excess weight, and 38.3 percent of patients in the experimental
group lost at least 25 percent of their excess weight.
The
clinical study did not meet its original endpoint, which was that the
experimental group lose at least 10 percent more excess weight than the
control group. However, an FDA Advisory Committee (the Gastroenterology and Urology Devices Panel)
found the 18-month data supportive of sustained weight loss, and agreed
that the benefits of the device outweighed the risks for use in
patients who met the criteria in the device’s proposed indication.
In
considering the benefits and risks of the device in its review of the
Maestro Rechargeable System, the FDA considered the clinical study and
the Panel’s recommendations. Additionally, the Agency looked at an
FDA-sponsored survey relating to patient preferences of obesity devices
that showed a group of patients would accept risks associated with this
surgically implanted device for the amounts of weight loss expected to
be provided by the device.
As part of the approval, the
manufacturer must conduct a five year post approval study that will
follow at least 100 patients and collect additional safety and
effectiveness data including weight loss, adverse events, surgical revisions and explants and changes in obesity-related conditions.
Serious
adverse events reported in the clinical study included nausea, pain at
the neuroregulator site, vomiting, as well as surgical complications.
Other adverse events included pain, heartburn, problems swallowing,
belching, mild nausea and chest pain.
The Maestro Rechargeable System is manufactured by EnteroMedics of St. Paul, Minnesota.
The
FDA, an agency within the U.S. Department of Health and Human Services,
protects the public health by assuring the safety, effectiveness, and
security of human and veterinary drugs, vaccines and other biological
products for human use, and medical devices. The agency also is
responsible for the safety and security of our nation’s food supply,
cosmetics, dietary supplements, products that give off electronic
radiation, and for regulating tobacco products.