VALENCIA, Calif. — It seems that MannKind has experienced a setback with a drug designed to control hyperglycemia in Type 1 and Type 2 diabetes patients.

The Food and Drug Administration on Thursday issued a complete response letter to the drug maker regarding Afrezza (insulin human [rDNA origin]) inhalation powder. The regulatory agency requested that the company conduct two clinical trials, one in patients with Type 1 diabetes and one in patients with Type 2 diabetes, with its next-generation inhaler, to assure it works as effectively as MedTone, its predecessor.

"While we are disappointed with the complete response letter, we are encouraged that the FDA is asking for clinical studies only to confirm the bridging and handling of the next-generation device in order to compare it to the device used in our extensive clinical program," said MannKind's chairman and CEO Alfred Mann. "We remain committed to working with the FDA to make Afrezza available to people with diabetes."