Thermosensitive Gel Nasal Spray With Exosomes, Azelastine, and Interferon for Acute Phase of Chronic Sinusitis

A Single-Centre, Randomised, Double-Blind, Placebo-Controlled Exploratory Clinical Study of a Thermosensitive Gel Nasal Spray Containing Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes, Azelastine and Recombinant Human Interferon α-2b for the Treatment of Chronic Rhinosinusitis (Acute Phase)

This study tests a new nasal spray for adults (18-65 years) with chronic sinusitis experiencing an acute phase. The spray contains a temperature-sensitive gel that turns into a soft gel inside the nose to slowly release three active ingredients: stem cell exosomes (to repair nasal lining), azelastine (an antihistamine and anti-inflammatory drug), and interferon alpha-2b (an antiviral agent). The study aims to evaluate safety and see if the spray can reduce symptoms, fight viruses, and improve quality of life. Participants will be randomly assigned to one of three groups: triple spray, dual spray (without exosomes), or placebo (gel only). Treatment is twice daily for 4 weeks, with follow-up visits up to day 90.

This exploratory, single-centre, randomised, double-blind, placebo-controlled study enrolls 108 participants (allowing 20% dropout) in a 1:1:1 ratio. Group A receives thermosensitive gel + exosomes (1×10^10 particles/mL) + azelastine (0.1%) + interferon α-2b (1×10^5 IU/mL). Group B receives gel + azelastine + interferon (without exosomes). Group C receives blank gel. The gel matrix (Poloxamer 407 18% + chitosan hydrochloride 0.5%) is liquid at room temperature and gels at nasal temperature (33-35°C). Treatment duration is 28 days (twice daily, 2 sprays per nostril). Single-spray doses: exosomes 2×10^9 particles, azelastine 0.2 mg, interferon 2000 IU. Follow-up at day 42 and day 90. Primary outcome: safety (adverse events, CTCAE v5.0). Secondary outcomes: Lund-Kennedy score, SNOT-22, VAS, response rate, SF-36. Exploratory: viral clearance, inflammatory cytokines, bacterial load, mucosal barrier markers. The study is conducted at The First Affiliated Hospital of Xinxiang Medical College. Ethics approval obtained. Results will be published.

Inclusion Criteria:

• Age 18 to 65 years, both genders
• Diagnosis of chronic rhinosinusitis according to Chinese guidelines (2018) or EPOS 2020, duration >12 weeks
• Lund-Kennedy endoscopic score ≥4
• SNOT-22 score ≥30
• Nasal symptoms stable in past month, or acute flare-ups not requiring systemic antibiotics/steroids
• Voluntary signed informed consent

Exclusion Criteria:

• Sinus surgery within past 6 months or anatomical abnormalities requiring reoperation
• Allergic fungal rhinosinusitis, odontogenic rhinosinusitis, or nasal polyps
• Primary ciliary dyskinesia, cystic fibrosis, or severe immunodeficiency
• Use of systemic glucocorticoids, immunosuppressants, or antibiotics within past 4 weeks
• Use of intranasal glucocorticoids, antihistamines, or leukotriene receptor antagonists within past 2 weeks
• Hypersensitivity to poloxamer, chitosan, azelastine, or interferon
• Pregnant, breastfeeding, or planning to become pregnant
• Uncontrolled severe systemic diseases (diabetes, hypertension, autoimmune diseases)
• Malignancy within past 5 years
• Participation in other clinical trials