吸入制剂是指通过吸入途径将药物递送至呼吸道和/或肺部以发挥局部或全身作用的制剂，主要用于呼吸系统疾病及其他疾病的治疗。因其独特的给药方式和多种影响因素，不仅给非临床和临床研究中的关键研究参数（如肺沉积剂量）的种属间换算带来了挑战和不确定性，也增加了首次临床试验起始剂量拟定的难度。梳理国内外相关技术指导原则和文件，结合审评实践和已上市产品的研发案例探讨吸入制剂首次临床试验起始剂量推算的关注点，以期为吸入制剂首次临床试验起始剂量的拟定提供参考。

Inhaled preparations refer to preparations that deliver drugs to the respiratory tract and/or lungs through inhalation to exert local or systemic effects, mainly used for the treatment of respiratory and other diseases. Due to its unique administration route and multiple influencing factors, it not only brings challenges and uncertainties to the inter species conversion of the key research parameter, such as lung deposition dose, in non clinical and clinical studies, but also increases the difficulty of calculating the first-in-human（FIH） dose. This article summarizes relevant technical guidance and files at home and abroad, and combines review practice and research and development cases of marked products, in order to provide reference for the calculation of FIH dose of inhalation formulations.

R944