Amylin and Takeda halt obesity drug study

Amylin Pharmaceuticals and Takeda Pharmaceutical have suspended a phase II clinical study of an investigational obesity treatment that combines pramlintide, which is the active ingredient in Amylin's marketed diabetes drug Symlin, with metreleptin, an analogue of the hormone leptin.

The companies said they had voluntarily halted the study in order to investigate "a new antibody-related laboratory finding with metreleptin treatment in two patients who participated in a previously completed clinical study of obesity."

Some of the data from the earlier study suggests that the two patients produced neutralising antibodies that can block the effectiveness of a drug, an Amylin spokesperson told the news service Bloomberg.

In February 2010, Amylin and Takeda announced that the combination product for obesity had been selected to advance toward phase III development based on encouraging results from a 52-week placebo-controlled phase II extension study in which the combination met the key target criteria of sustained and robust weight loss.

Metreleptin is an analogue of human leptin, a neurohormone secreted by fat cells that helps regulate energy metabolism and body weight. More than 1,200 overweight or obese people have received metreleptin in clinical trials, several of which were 16 weeks or longer in duration, according to the companies.

In late 2010, Amylin began submission of a rolling US Biologics Licensing Application for metreleptin as monotherapy to treat diabetes and/or hypertriglyceridaemia (high levels of triglycerides in the bloodstream) in patients with rare forms of lipodystrophy. The lipodystrophy development programme for metreleptin is not affected by the halted study of the combination therapy, according to the company.

Earlier this month, Amylin announced disappointing results for its experimental drug Bydureon, co-developed by Eli Lilly as a longer acting version of Byetta for type 2 diabetes.