The long struggle by Boston-based I2o Therapeutics Inc.’s business unit Intarcia Therapeutics to get long-lasting exenatide for diabetes onto the market ended with a final thumbs-down from the U.S. FDA because of safety concerns. At issue was ITCA-650, a twice-yearly implantable exenatide-device combo meant to improve glycemic control in adults with type 2 diabetes.

Safety concerns overrode benefit when the U.S. FDA’s Endocrinologic and Metabolic Drugs Advisory Committee (EMDAC) voted unanimously, 19-0, Sept. 21 that the potential risks of Intarcia Therapeutics’ ITCA-650 outweighed the compliance and A1C-lowering benefits the twice-yearly implantable exenatide-device combination product could provide for adults with type 2 diabetes.

Once upon a time, Intarcia Therapeutics Inc. was a biotech unicorn valued at $3.5 billion. Its allure was its implantable Medici drug delivery system that consisted of a mini pump about the size of a matchstick. But a unicorn’s life is never completely charmed. Intarcia faced obstacles along the way – two complete response letters from the U.S. FDA and the denials of three formal dispute resolution requests. Now it looks like this story won’t have a happy ending.