Clinical Improvement and Immune Signatures Following Platelet-Rich Plasma Therapy for Post-Viral Olfactory
Vivienne M Li1,2, Jennifer S Lee1,2, Arwa Kurabi2
1University of California, San Diego School of Medicine, La Jolla, California, USA.
International Forum of Allergy & Rhinology
|August 14, 2026
Summary
Platelet-rich plasma (PRP) therapy offers modest clinical improvement for post-viral olfactory dysfunction (PVOD). PRP may enhance immune remodeling, reducing inflammation and activating repair pathways for better smell function.
Area of Science:
- Otolaryngology
- Immunology
- Regenerative Medicine
Background:
- Post-viral olfactory dysfunction (PVOD) is a challenging condition with unclear biological mechanisms.
- Platelet-rich plasma (PRP) shows promise for treating refractory PVOD.
- This study investigates clinical outcomes and proteomic changes after PRP treatment for PVOD.
Purpose of the Study:
- To evaluate the clinical efficacy of PRP injections in patients with refractory PVOD.
- To identify proteomic and cytokine profile alterations following PRP therapy.
- To explore the biological mechanisms underlying PRP's effects on PVOD.
Main Methods:
- Adults with PVOD received bilateral PRP injections into the olfactory clefts.
- Olfactory function was assessed using subjective ratings and the University of Pennsylvania Smell Identification Test (UPSIT).
- Paired olfactory mucus samples were analyzed for proteomic changes using the Olink Target 48 immune panel.
Main Results:
- 47% of patients reported subjective improvement, and 53% achieved minimal clinically important difference.
- Mean UPSIT scores improved by +3.1 points post-treatment.
- PRP altered cytokine profiles, increasing CSF2 and IL-1β, and decreasing IL-6 and IL-33, suggesting immune remodeling and repair activation.
Conclusions:
- PRP therapy is associated with modest clinical benefits in refractory PVOD.
- Responder analyses indicate PRP promotes immune remodeling, reducing inflammatory signals and activating reparative pathways.
- These findings support the biological plausibility of PRP for PVOD and warrant further research.
