Ease of use of tobramycin inhalation powder compared with nebulized tobramycin and colistimethate sodium: a crossover study in cystic fibrosis patients with pulmonary Pseudomonas aeruginosa infection

Abstract

Background: This study assessed the ease of use of tobramycin inhalation powder (TIP) administered via T-326 inhaler versus tobramycin inhalation solution (TIS) and colistimethate sodium (COLI), both administered via nebulizers, for the treatment of chronic pulmonary Pseudomonas aeruginosa infection in patients with cystic fibrosis (CF).

Methods: A real-world, open-label, crossover, interventional phase IV study was conducted in CF patients aged ⩾6 years with forced expiratory volume in 1 second (FEV₁) ⩾25% to ⩽90% predicted. Patients were assigned to one of the three treatment arms in Cycle 1; all patients received TIP in Cycle 2. Each cycle consisted of 28 days on and 28 days off the treatment.

Results: A total of 60 patients [mean (standard deviation) age, 27.6 (8.4) years] were allocated to three treatment arms [TIS/TIP ( n = 14); COLI/TIP ( n = 28); TIP/TIP ( n = 18)] in Cycle 1. The mean total administration time, which included device setup and cleaning, in Cycle 1 versus Cycle 2 for TIS/TIP, COLI/TIP, and TIP/TIP arms were 37.0 versus 5.0 min, 16.4 versus 3.8 min, and 4.2 versus 3.4 min, respectively. The difference in mean total administration time was significantly shorter in Cycle 2 than in Cycle 1 for TIS/TIP ( p = 0.0112) and COLI/TIP ( p = 0.0016) arms. Overall, 12 patients were found to have contaminated devices across the two treatment cycles. In the TIP/TIP arm, no contamination of the T-326 inhaler was observed in either cycle. Treatment satisfaction, assessed by the Treatment Satisfaction Questionnaire for Medication and ACCEPT® questionnaire, was better overall for TIP compared with TIS and COLI. There were no unexpected adverse events and most were mild or moderate in intensity.

Conclusion: The T-326 inhaler used to deliver TIP was easy to use, required shorter total administration time, and was much less frequently contaminated than the nebulizers. The safety findings observed for TIP were generally consistent with its established safety profile.

Trial registration: ClinicalTrials.gov NCT01844778.

Keywords: Pseudomonas aeruginosa; T-326 inhaler; device contamination; ease of use; nebulizer; tobramycin.

Figure 1.

(a) Study design, (b) Patient disposition. ^*Patients on continuous COLI were to observe a 24-h COLI-free period before the start of TIP at Visit 4. Note: Patients with COLI could follow a cyclic or noncyclic regimen dependent on local treatment practice. AEs, adverse events; COLI, colistimethate sodium; TIP, tobramycin inhalation powder; TIS, tobramycin inhalation solution.