Objective:

To evaluate the effect of ribavirin nasal spray on symptoms of allergic rhinitis by reducing nasal commensal viruses.

Approach:

• Clinical Trial: A phase 2 randomized, double-blind, placebo-controlled trial involving 42 patients with allergic rhinitis, comparing ribavirin nasal spray (22 patients) to placebo (20 patients) over 4 weeks.
• Laboratory Studies: Parallel studies in mouse models to investigate the biological effects of reducing nasal commensal viruses.

Key Findings:

• Ribavirin treatment resulted in lower Total Nasal Symptom Scores compared to placebo after 4 weeks.
• Improvements were also noted in Visual Analog Scale and Rhinitis Control Assessment Test scores.
• Ribavirin reduced nasal commensal virus abundance, while the placebo group showed no significant change.
• No serious adverse events or adverse drug reactions were reported.
• Higher nasal commensal virus abundance correlated with symptom severity and interferon-stimulated gene expression.

Interpretation:

The findings suggest that reducing nasal commensal viruses may improve allergic rhinitis symptoms, although further research is needed.

Limitations:

• The study was small and conducted at a single center, necessitating larger multicenter phase 3 trials for confirmation.
• Mechanistic evidence primarily derived from mouse models.
• Specific nasal commensal viruses identified have not been established as causal drivers of allergic rhinitis in humans.
• Effectiveness and safety of ribavirin spray remain exploratory.

Conclusion:

Reducing nasal commensal viruses may represent a novel therapeutic strategy for allergic rhinitis, pending validation in larger studies.

Sources:

• Signal Transduction and Targeted Therapy