Amylin Pharmaceuticals and Takeda Pharmaceutical have suspended clinical activities in an ongoing phase II study examining the safety and effectiveness of the investigational combination therapy pramlintide/metreleptin for the treatment of obesity.

The clinical study was voluntarily halted to investigate a new antibody-related laboratory finding with metreleptin treatment in two patients who participated in a previously completed clinical study of obesity, according to the San Diego-based Amylin and Osaka, Japan-based Takeda.

"We have taken this precaution so that we can thoroughly investigate this finding," said Orville Kolterman, MD, senior vice president and chief medical officer of Amylin. "Together with our partner, Takeda, we are committed to working closely with clinical investigators, regulators and outside experts to determine the best path forward."

The companies noted that pramlintide acetate is a synthetic analog of the natural hormone amylin, a neurohormone secreted by the pancreas that plays a role in the regulation of appetite, food intake and postprandial glucose concentrations. To date, approximately 8,000 individuals have received pramlintide in clinical trials, including more than 950 in obesity studies. Metreleptin (methionyl recombinant leptin) is an analog of human leptin, a neurohormone secreted by fat cells that plays a role in the regulation of energy metabolism and body weight. To date, more than 1,200 overweight or obese individuals have received metreleptin in clinical trials, several of which were 16 weeks or longer in duration.