Phase 1 Studies to Assess Inhaled Seralutinib as a Perpetrator or a Victim of Drug‐Drug Interactions in Healthy Participants

Seralutinib, an inhaled, small-molecule tyrosine kinase inhibitor in clinical development for the treatment of pulmonary arterial hypertension (PAH), was evaluated for its potential as a perpetrator or victim of a metabolic and transporter-based drug-drug interactions in 2 phase 1 studies. In study 1, 24 participants received a cocktail of probe substrates: caffeine (CYP1A2), montelukast (CYP2C8), flurbiprofen (CYP2C9), midazolam (CYP3A), and pravastatin (OATP1B1/1B3), plus digoxin (P-gp) with or without seralutinib. In study 2, 19 participants received seralutinib with/without itraconazole, a strong CYP3A inhibitor, or fosaprepitant, a weak CYP3A inhibitor. Geometric least-squares mean ratios and 90% confidence intervals for maximum observed concentration (C