After review of the meal challenge data from the Original Protocol design, it became apparent that the TI Inhalation Powder, insulin lispro, and Exubera doses were not well matched, and resulted in significantly higher insulin exposure following insulin lispro than the two inhaled treatments. All meal challenge visits were completed for the 18 subjects enrolled. However, the glucose clamp visits were discontinued since it was discovered that a direct comparison between the treatments was not possible.