Mean ± SD change from baseline in FEV1 (A) and DLCO (B). Treatment group difference = EXU − SC. Although FEV1 and DLCO declined in each group during the course of the study, differences between the two treatment groups remained small (<2% of baseline), developed early (during the first 3 months), and did not progress further for up to 2 years. ▪, EXU; ○, SC insulin.