MannKind finally seems to have a clear pathway to follow as it tries to bring its inhaled insulin product Afrezza to market, following a "successful" meeting with the US FDA, says chief operating officer Hakan Edstrom.

The company sought the meeting with the FDA after the agency rejected the inhaled insulin product in January for the second time. The drug had previously been turned down in March 2010, and the second rejection prompted the US company to slash its workforce by more than 40%.

MannKind held a meeting with the FDA on Wednesday to agree the design of two clinical studies that should support approval of Afrezza, a rapid-acting mealtime insulin delivered via its Dreamboat second-generation inhaler.

"We held a successful meeting with the FDA yesterday, confirming the protocols for the type 1 and type 2 studies, said Edstrom.  "We were also encouraged to proceed promptly with the initiation of both clinical trials."

The FDA had previously requested that MannKind conduct two clinical trials with the Dreamboat inhaler, one in type 1 and another in type 2 diabetes). At least one trial should include a treatment group using the previously studied MedTone inhaler in order to obtain a head-to-head comparison of the pulmonary safety data for the two devices, according to the agency.

The first of the two studies is codenamed 171, and will be conducted in patients with type 1 diabetes and compare standard rapid-acting insulin with Afrezza in both inhaler devices. The second study - called 174 - will assess Afrezza using the next-generation inhaler in patients with type 2 diabetes who are inadequately controlled on metformin with or without a second or third oral medication.

An inhaled insulin from Pfizer called Exubera was on the market for a short time in 2006-2007, but was withdrawn from the market on poor sales and concern about the risk of dosing errors with the formulation. The withdrawal prompted other companies developing inhaled insulins - Eli Lilly/Alkermes and Novo Nordisk/Aradigm - to drop their own programmes.