Delivery of dornase alfa via breath-actuated nebulizer: In-vitro measures of performance

RATIONALE: Pulmozyme® is indicated in the management of cystic fibrosis to improve lung function and is typically delivered by continuous nebulization to tidal-breathing patients. During the exhalation phase medication is discharged into the environment. Breath-actuated nebulizers (BANs) only operate during inhalation. This study was designed to evaluate medication output from a BAN configuration (AeroEclipse®-XL/Ombra® compressor (AE-XL); TMI) compared with a continuous nebulizer configuration (PARI LC-plus®/PARI Boy®SX compressor (LC+)). METHODS: Each nebulizer was filled with a 2.5 mL Pulmozyme® ampoule (1 mg/mL dornase alfa) and run until onset of sputtering. Aerosol was captured by a filter at the mouthpiece, and the nebulizer connected to a breathing simulator (tidal volume = 600 mL; duty cycle = 33%; rate = 10 cycles/min). Fine droplet mass (µg < 5.4 µm diameter (FM pulm )) and fine droplet fraction (% < 5.4µm, (FMF pulm ) were determined by Next Generation Impactor operated at 15 L/min with assay for dornase alfa by HPLC. RESULTS: Device (n=10) FMFpulm (%) FMpulm (μg) AE -XL / Ombra 83.3 ± 2.2 428 ± 40 LC+ / Pari Boy SX 83.8 ± 2.2 349 ± 62 CONCLUSIONS: The AE-XL BAN exhibited a little higher delivery of Pulmozyme® to the LC+, although well within the demonstrated patient tolerability (Pulmozyme® Nebuliser solution SPC, Roche). In addition, clinicians should be aware that, unlike the LC+, the operation of the BAN only occurs due to patient inhalation thereby eliminating nearly all fugitive emissions and ensuring delivery to the patient at their own pace.