Detailed review findings of EMPOWER study to evaluate the Maestro System released

Nov 12 2009

EnteroMedics Inc. (NASDAQ: ETRM), the developer of medical devices using neuroblocking technology to treat obesity and other gastrointestinal disorders, today announced preliminary findings from its ongoing detailed review of its EMPOWER™ study, a randomized, double-blind, controlled pivotal study designed to evaluate the safety and efficacy of the Maestro® System in the treatment of obesity. On October 2, 2009, the Company announced that the study did not meet its primary and secondary efficacy endpoints, as results in the control and treatment arms were statistically indistinguishable, while achieving all of its safety endpoints.

The ongoing detailed review suggests that vagal blocking therapy may promote safe and effective weight loss as an adjunct to behavioral support, diet and exercise in morbidly obese patients. The review further suggests that these effects were evident in both the treatment and control arms. The Company is continuing a comprehensive analysis of all clinical, statistical, and engineering data to understand this finding. Based on the analysis to date, the control arm of the trial, which was intended to be inactive, apparently provided a low-intensity blocking signal that introduced VBLOC Therapy in human subjects.

The Company is informing patients and physicians of the following study findings:

• The EMPOWER study met all of its safety goals, including the finding that there were no therapy-related serious adverse events reported across the entire study population;
• Patients who met or exceeded the prescribed nine hours of daily device use>
• Patients that did not meet the prescribed nine hours of daily device use>
• For all patients>
• For those patients with a diagnosis of hypertension>

As of today, in accord with the study protocol, 252 patients remain in the EMPOWER study and are receiving VBLOC Therapy. Consistent with the study protocol, physicians are encouraging their patients to use the Maestro System for a minimum of the prescribed 9 hours per day.

“The EMPOWER study demonstrated a remarkable level of safety for an implanted medical device,” added James W. Freston, M.D., Ph.D., Professor of Medicine and Clinical Pharmacology (emeritus), University of Connecticut Health Center and Chairman of the EMPOWER study Data Safety Monitoring Board.

“Results from the two arms of the EMPOWER study as well as from our previous VBLOC Therapy trials were consistent with each other, suggesting a pattern of positive clinical outcome when blocking the vagus nerve,” said President and CEO Mark B. Knudson, Ph.D. “The apparent control arm effect, while unexpected, may be a scientifically important addition to our understanding of neuromodulation. We are taking steps to discuss the outcome of this study with the FDA to determine the appropriate regulatory path forward for the Maestro System as a treatment for morbid obesity.”

The Company will discuss these findings in detail in a conference call and slide presentation today at 8:00 AM Eastern Standard Time.