Study 2

Study 2 was a randomized, three-cycle, two-arm trial. Each cycle comprised of 28 days on treatment followed by 28 days off treatment. The first cycle was double-blind, placebo-controlled with eligible patients randomized 1:1 to TOBI Podhaler (4 x 28 mg capsules twice daily) or placebo. Upon completion of the first cycle, patients who were randomized to the placebo treatment group received TOBI Podhaler for Cycles 2 and 3. The total treatment period was 24 weeks.

A total of 95 patients were randomized into Study 2 and received TOBI Podhaler (n=46) or placebo (n=49) in Cycle 1. All patients were less than 22 years of age (mean age 13.3 years) and had not received inhaled antipseudomonal antibiotics within four months prior to screening; 56% were female and 84% were Caucasian. This study was stopped early for demonstrated benefit and the primary analysis used the set of patients included in the interim analysis (n=79); 16 patients did not have data on the primary endpoint at that time. Of the 79 patients included in the interim analysis, 18 patients were excluded due to a failure to meet spirometry quality review criteria as determined by an external review panel. This resulted in a total of 61 patients, 29 in the TOBI Podhaler arm and 32 in the placebo arm, who were included in the primary analysis.

In the primary analysis, TOBI Podhaler significantly improved lung function compared with placebo as measured by the relative change in FEV1 % predicted from baseline to the end of Cycle 1 dosing. This analysis adjusted for the covariates of baseline FEV1 % predicted, age, and region, and imputed for missing data. Treatment with TOBI Podhaler and placebo resulted in relative increases in FEV1 % predicted of 12.54% and 0.09%, respectively (LS mean difference = 12.44%; 95% CI: 4.89, 20.00; p=0.002). Analysis of absolute changes in FEV1 % predicted showed LS means of 6.38% for TOBI Podhaler and -0.52% for placebo with a difference of 6.90% (95% CI: 2.40, 11.40). Improvements in lung function were achieved during the subsequent cycles of treatment with TOBI Podhaler, although the magnitude was reduced (Figure 1).

The percentage of patients using new antipseudomonal antibiotics in Cycle 1 was greater in the placebo treatment group (18.4%) compared with the TOBI Podhaler treatment group (13.1%). During the first cycle, 8.7% of TOBI Podhaler patients and 10.2% of placebo patients were treated with parenteral antipseudomonal antibiotics. In Cycle 1, two patients (4.4%) in the TOBI Podhaler treatment group required respiratory-related hospitalizations, compared with six patients (12.2%) in the placebo treatment group.

Figure 1 – Study 2: Mean relative change in FEV1 % predicted from baseline in Cycles 1-3 by treatment group

Error bars represent the mean relative change (95% CI)

Study 3

Study 3 was a randomized, double-blind, placebo-controlled trial, similar in design to Study 2. Eligible patients were randomized 1:1 to receive TOBI Podhaler (4 x 28 mg capsules twice daily) or placebo for one cycle (28 days on-treatment and 28 days off-treatment).

A total of 62 patients were randomized into Study 3 and allocated to TOBI Podhaler (n=32) or placebo (n=30). All patients were less than 22 years of age (mean age 12.9 years) and had not received inhaled antipseudomonal antibiotics within 4 months prior to screening