Table 2.

Clinical trials using inhalation as the delivery method for COVID-19 as an exemplar respiratory disease.

NCT No.	Title	Enrolled	Intervention	Dose	Phase	Status
NCT04276987	A Pilot Clinical Study on Aerosol Inhalation of the Exosomes Derived From Allogenic Adipose Mesenchymal Stem Cells in the Treatment of Severe Patients With Novel Coronavirus Pneumonia	30	Single-group assignment	MSC derived exosomes 5 Times aerosol inhalations of MSCs-derived exosomes (2.0 × 108 nano vesicles/3 mL at Days 1, 2, 3, 4 and 5	Phase 1	Not yet recruiting
NCT04389385	Aerosol Inhalation of the Exosomes Derived From Allogenic COVID-19 T Cell in the Treatment of Early Stage Novel Coronavirus Pneumonia	60	Single-group assignment	Specific T cell-derived exosomes (CSTC-Exo) Aerosol inhalation of CSTC-Exo (2.0 × 108 nanovesicles/3 mL at Day 1,2,3,4 and 5, 5 times daily	Phase 1	Active, not recruiting
NCT04473170	Study Evaluating the Safety and Efficacy of Autologous Non-Hematopoietic Peripheral Blood Stem Cells in COVID-19 (SENTAD-COVID)	146	Parallel assessment	Autologous Non-Hematopoietic Peripheral Blood Stem Cells (NHPBSC) therapy as add-on COVID-19 standard care	Phase 1 Phase 2	Completed