This is an exploratory, randomized, single-blind, placebo-controlled, multiple-dose, dose-escalation clinical study. The study aims to evaluate the safety and preliminary efficacy of nebulized inhalation of Human Umbilical Cord Mesenchymal Stem Cell-Derived Extracellular Vesicles (hUCMSC-EVs) in patients with interstitial lung disease (ILD).
This study is designed to include three sequential dose cohorts-low, medium, and high-with dose escalation proceeding in an ascending order. Eligible subjects will be enrolled and randomized sequentially, with a planned enrollment of 8 subjects per cohort. Within each cohort, subjects will be randomly assigned in a 3:1 ratio to receive either hUCMSC-EVs or saline placebo.