While triazoles are currently the preferred first-line agents to treat and prevent IPA, systemic triazoles have been associated with class-related DDIs that often limit their use.9,10,12 Several CYP enzymes, especially CYP3A4, and the P-gp membrane transporter metabolize and are inhibited by triazoles.10 The in vitro and Phase 1 data reported here suggest that inhaled opelconazole has the potential to overcome some of the limitations associated with systemic triazoles, especially with respect to DDIs. The gene discussed is PPIG; the disease is Ito hypomelanosis.