Particle size and gastrointestinal absorption influence tiotropium pharmacokinetics: a pilot bioequivalence study of PUR0200 and Spiriva HandiHaler.

Pharmacokinetic bioequivalence indicative of lung deposition and efficacy can be achieved by matching the reference product ISM. Due to reduced oral deposition and more efficient lung delivery, PUR0200 results in a lower AUC0-t than Spiriva HH due to reduced absorption of drug from the gastrointestinal tract.