Could inhaled stem cell particles ease allergies and asthma?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Aged 18-60 years, regardless of gender; 2. Patients with moderate to severe allergic rhinitis (with sleep/work/study/daily activity impairment or distressing symptoms) meeting the diagnostic criteria of the international Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines, positive for at least one inhalant allergen skin prick test, and concurrent asthma complying with the Global Initiative for Asthma (GINA) 2022 guidelines; 3. Suboptimal response to antiallergic medication treatment for one year prior to enrollment; 4. Patients who decline allergen-specific immunotherapy, or have no available specific therapy for the relevant allergen, or failed allergen-specific immunotherapy; 5. Females of childbearing potential must agree to avoid pregnancy during study participation and for 30 days after the final visit; 6. Subjects or their legal representatives must be able to sign the informed consent form and comply with the study requirements for medication administration and follow-up. Exclusion Criteria: 1. Complicated with other nasal and sinus diseases that may affect the reasonable assessment of efficacy and/or safety; 2. Suffering from uncontrolled asthma or poorly controlled asthma symptoms; 3. Suffering from malignant tumors, severe immune diseases, long-term use of immunosuppressants, or immunodeficiency; 4. Having unstable conditions due to respiratory tract infection and/or acute asthma exacerbation within 4 weeks prior to the initial screening visit; 5. Currently receiving treatment with beta-blockers or angiotensin-converting enzyme (ACE) inhibitors; 6. Suffering from mental illnesses; 7. Suffering from severe systemic diseases, such as cases of peptic ulcers, diabetes mellitus, and heart failure; 8. Specific infections such as syphilis, leprosy, and tuberculosis; 9. Females who are currently pregnant, planning to become pregnant soon, or breastfeeding; 10. Patients who are currently participating in other clinical trials or have participated in other clinical trials within 30 days prior to the initial screening visit; 11. Patients who are currently receiving allergen desensitization therapy or biologic therapy; 12. Positive for hepatitis B surface antigen, hepatitis C virus antibody, syphilis serological antibody, or human immunodeficiency virus (HIV) antibody; 13. In addition to the above conditions, patients will be excluded if the investigators consider them unsuitable for participation in this clinical study for other reasons.