Clinical Pharmacokinetics of Inhaled Drugs for Pulmonary Hypertension

Pulmonary hypertension (PH) is a serious condition characterized by elevated blood pressure in the pulmonary arteries. Current treatment approaches mainly focus on using vasodilator agents to reduce pulmonary blood pressure and improve blood flow. Inhalation treatments offer targeted delivery to the lungs, improving efficacy and reducing systemic side effects. Understanding the pharmacokinetics (PK) of the molecules used in the inhalation treatment is crucial for dose optimization and drug product development. This review examines the clinical PK characteristics of key inhaled PH drugs (approved and investigational agents), including epoprostenol, iloprost, treprostinil, vardenafil, imatinib, seralutinib, MK-5475, milrinone, and sodium nitrite. We provide detailed analyses of their PK parameters and explore how disease conditions, inter-subject variability, and inhaled formulations and devices impact clinical PK characteristics. Future research would focus on how disease-specific factors affect drug behavior and the prediction of pulmonary drug concentrations. This will support more precise drug delivery and personalized treatment strategies for PH.