Stem cell therapies for chronic obstructive pulmonary disease: mapping the global clinical trial landscape

Background Stem cell therapies have emerged as a promising strategy for repairing structural damage and modulating inflammation in chronic obstructive pulmonary disease (COPD). However, a comprehensive characterization of the global clinical trial landscape remains lacking. Methods We retrospectively analyzed clinical trials of stem cell therapy for COPD registered in the Trialtrove database up to October 1, 2025, supplemented by cross-referencing with ClinicalTrials.gov. Key trial characteristics were independently extracted and cross-checked by 2 investigators. Results A total of 43 eligible trials were identified. Early-phase studies (Phase I–II) accounted for over 80% of all trials. Mesenchymal stromal cell (MSC)-based therapies and mixed cell populations each accounted for 34.9% of registered trials, followed by bronchial basal progenitor cell-based therapies (23.3%). Among 25 completed trials, only 11 publicly disclosed results. Available findings indicated no major short-term safety concerns for the specific cell products evaluated, whereas efficacy outcomes remained heterogeneous. Academic institutions sponsored most trials, while industry-sponsored studies showed a higher proportion of terminated or inactive trials. The United States and China accounted for the largest numbers of registered trials, although Brazil contributed the greatest number of publicly available outcome reports. Conclusions Stem cell therapy for COPD remains in an early exploratory stage, with low result-disclosure rates and limited late-phase evidence. Standardized trial design, improved data transparency, and large-scale randomized controlled trials are urgently needed to advance clinical translation.