Ryan, who has a buy rating on Pfizer, said "many doctors" believe some patients will have trouble gauging their ideal dose when inhaling Exubera. The best potential customers will be "motivated patients who were new to insulin therapy," she said. Ryan doesn't own shares, but her firm has provided services to Pfizer. Several researchers at the ADA convention pointed out that technology improves over time, and that's been the case for insulin administration. Where once big needles were used for injections, now there are much smaller devices and pumps. The first insulin pump was the size of a backpack. Now, they're as small as cell phone or pagers. As for insulin inhalers, Pfizer and Nektar will be pressed to improve Exubera not only for greater patient convenience, but also because of competition. Several companies are testing devices resembling anything from a cell phone to an asthma inhaler. Some potential competitors appear to offer "sleeker devices and more convenient administration," Arnold says. The closest competitors are believed to be at least two to three years behind Exubera. Among the other hopefuls are Eli Lilly ( LLY), Alkermes ( ALKS) MannKind ( MNKD) and Novo Nordisk ( NVO). Attempts at creating an inhaled insulin are nothing new. In 1925, German scientists reported on experiments that showed patients would need to inhale too much insulin for this approach to be effective, said Lutz Heinemann, CEO of business development at the Profil Institute for Metabolic Research in Neuss, Germany. Speaking at the ADA meeting, he said each version of inhaled insulin will be different because of how the drug is formulated and how the delivery system works, and they can't be compared accurately without head-to-head tests. Heinemann has been a consultant to many diabetes-research companies. Pfizer is supporting its Exubera launch with an extensive education campaign for doctors and patients, an effort it started soon after the Food and Drug Administration approved the drug on Jan. 27. Exubera is set to be available starting in mid-July.