Balancing efficacy and portability: comparative in vitro/in vivo evaluation of MDI PLUS® versus AeroChamber2go™ spacers for aerosol delivery.

BACKGROUND

The Global Initiative for Asthma (GINA) recommended using spacers or valved holding chambers to counter the common problems of poor pressurized metered dose inhaler (pMDI) technique. However, many subjects avoid using conventional spacers because they are bulky and inconvenient to carry around in public.

OBJECTIVE

We aimed to compare the novel, MDI PLUS® spacer, with AeroChamber2go™ on their in vitro and in vivo aerosol performance, as well as their user training requirements.

METHODS

In vitro, aerosol characteristics were assessed using an Andersen cascade impactor at 28.3 L/min with Ventolin® pMDI (5 puffs, 100 µg/puff); HPLC quantified drug deposition on each stage. In vivo, 20 asthmatic subjects received 500 µg salbutamol via pMDI alone, and pMDI + AeroChamber2go™ or MDI PLUS®. Urine samples were collected at 30 min and cumulatively over 24 h after inhaler use, and salbutamol samples were extracted and assessed using HPLC. Ex vivo delivery and user inhaler mastery were also assessed.

RESULTS

The fine-particle dose increased from 94.98 µg (pMDI alone) to 128.45 µg with AeroChamber2go™ and 130.04 µg with MDI PLUS®, while the fine-particle fraction rose from 26.58% to 65.72% and 67.19%, respectively (p < .05). Thirty-minute urinary salbutamol excretion nearly doubled with both the MDI PLUS® and the AeroChamber2go, whereas systemic bioavailability over 24 h was significantly reduced from 143.35 µg with pMDI alone to approximately 60 µg with either device (p < .01). Notably, MDI PLUS required the fewest training sessions to master (1.03, p < .05).

CONCLUSIONS

Both the MDI PLUS® and the AeroChamber2go™ significantly enhanced pulmonary delivery and reduced systemic exposure compared to pMDI alone, while MDI PLUS® might potentially show a superior ease of use. These findings support the adoption of either device to optimize inhaler therapy.