AIMS: The number of dry powder inhaler (DPI) devices could increase because they are easier to use than a metered dose inhaler (MDI). Using urinary excretion, the relative bioavailability of salbutamol to the lungs and the body for a prototype DPI has been compared with an MDI. METHODS: A randomized, double-blind, two way crossover study compared the amount of salbutamol in the urine 30 min following inhalation of 2 x 100 micrograms salbutamol from a prototype DPI (Innovata Biomed Ltd, UK) and a Ventolin (Allen and Hanburys Ltd, UK) MDI in 10 volunteers. The amount of salbutamol and its metabolite, the ester sulphate conjugate, renally excreted up to 24 h post inhalation was also determined to evaluate the relative bioavailability of salbutamol to the body. RESULTS: The mean (s.d.) 30 min post-treatment urinary excretion for the prototype DPI and MDI was 8.4 (2.6) and 5.0 (1.9) micrograms, respectively (P < 0.001). The total amount of salbutamol and its ester metabolite excreted in the urine over the 24 h period after inhalation was 187.9 (77.6) and 137.6 (40.0) micrograms (P < 0.05). CONCLUSIONS: The prototype DPI delivered more salbutamol to the body and the lungs than a conventional MDI. This finding supports further development of the prototype DPI. The urinary salbutamol method is able to discriminate between two different inhalation systems.
RCT Entities:
AIMS: The number of dry powder inhaler (DPI) devices could increase because they are easier to use than a metered dose inhaler (MDI). Using urinary excretion, the relative bioavailability of salbutamol to the lungs and the body for a prototype DPI has been compared with an MDI. METHODS: A randomized, double-blind, two way crossover study compared the amount of salbutamol in the urine 30 min following inhalation of 2 x 100 micrograms salbutamol from a prototype DPI (Innovata Biomed Ltd, UK) and a Ventolin (Allen and Hanburys Ltd, UK) MDI in 10 volunteers. The amount of salbutamol and its metabolite, the ester sulphate conjugate, renally excreted up to 24 h post inhalation was also determined to evaluate the relative bioavailability of salbutamol to the body. RESULTS: The mean (s.d.) 30 min post-treatment urinary excretion for the prototype DPI and MDI was 8.4 (2.6) and 5.0 (1.9) micrograms, respectively (P < 0.001). The total amount of salbutamol and its ester metabolite excreted in the urine over the 24 h period after inhalation was 187.9 (77.6) and 137.6 (40.0) micrograms (P < 0.05). CONCLUSIONS: The prototype DPI delivered more salbutamol to the body and the lungs than a conventional MDI. This finding supports further development of the prototype DPI. The urinary salbutamol method is able to discriminate between two different inhalation systems.
Authors: Omar S Usmani; Martyn F Biddiscombe; Shuying Yang; Sally Meah; Eunice Oballa; Juliet K Simpson; William A Fahy; Richard P Marshall; Pauline T Lukey; Toby M Maher Journal: Respir Res Date: 2018-02-06