But MannKind may have better prospects because of its smaller inhaler and fast-acting insulin. Mr. Pfeffer says the MannKind inhaler fits neatly in one hand, and a second-generation versions the company is using in clinical trials is even smaller, the size of a whistle.  Patients put insulin doses — pre-packaged in cartridges — into the inhaler and turn the mouthpiece to release the insulin. The inhaler uses no electricity or compressed gas. “The patient’s breathing action does the job,” Mr. Pfeffer said. “The airflow through the cartridge allows the powder to be inhaled.”  The system now before the F.D.A. is for adults with Type 1 diabetes, which often begins in childhood, and Type 2 diabetes, which typically occurs when people are older.  Simos Simeonidis, a senior biotechnology analyst at the New York investment bank Rodman & Renshaw, who wrote a report on MannKind, said he expected its system to be available next year, if the F.D.A. approved. (Dr. Simeonidis has no stock in MannKind, but Rodman & Renshaw has provided investment banking services for it.)  Leonid Poretsky, chief of endocrinology at Beth Israel Medical Center in New York and director of the Gerald J. Friedman Diabetes Institute there, said that the MannKind system will face many problems even if it is approved.  “Injections today are essentially painless,” he said of the short, thin needles that are commonly used to inject insulin. And you don’t necesssarily “have to draw from a bottle into a syringe. Injections work so well that the advantages of a new route like this are unclear.”  Dr. Poretsky was also concerned about using the lungs to transport drugs. “It’s possible for people to stay on insulin for decades,” he said. “The whole issue of exposing the lungs to insulin for a long period of time has to be examined carefully.”  Dr. Gerald Bernstein, a New York-based endocrinologist who is a former president of the American Diabetes Association, agreed that the long-term use of inhalable insulin might carry risks for some patients. Dr Bernstein is vice president of the Generex Biotechnology Corporation, which is developing an insulin delivered through the lining of the mouth.  “It’s counterintuitive to use the fragile cells of the alveoli,” the tiny air sacs within the lungs, “to get insulin to the bloodstream,” he said. “The lungs were developed to transport gases, not proteins.”  Mr. Pfeffer of MannKind said that the company’s clinical data included no signs of damage to lungs.  DR. DAVID M. NATHAN, a professor of medicine at Harvard Medical School and director of the Massachusetts General Hospital Diabetes Center, said that even if safety issues were addressed, there could be other long-term problems with Afresa. He questioned whether MannKind’s inhalable product could achieve the same level of blood sugar control as that obtained with injections or insulin pumps.  “Insulin inhalers are tricky to use,” he said. “The amount you breathe in can be variable.” But he acknowledged that injections aren’t perfect and that many people would prefer to get their insulin in a more convenient way.  Mr. Pfeffer said trials by MannKind had shown a high consistency in doses by patients using the inhalers.  If all goes well at the F.D.A., Mr. Pfeffer says he thinks that MannKind will eventually go to market with the smaller dispenser now in trials. “The expectation,” he said, “is that we will launch with the whistle-sized inhaler” — which, by the way, was given the internal company name “Dreamboat” by its design team.  “Perhaps we’ll consider a different name, though,” he said.  A version of this article appears in print on October 11, 2009, on Page BU3 of the New York edition with the headline: A New Way to Inhale, Not Inject, Insulin. Order Reprints| Today's Paper|Subscribe
A small inhaler and insulin powder created by the MannKind Corporation are before the F.D.A. for marketing approval.