PANDORA: Evaluation of Platelet-rich Plasma in Non-tumoural Odour Disorders: a Descriptive Pilot Study.

NCT07473830 | Not Yet Recruiting

• 2 other identifiers: 69HCL24_11922025-A02847-42
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This is a prospective, single-center, single-arm, non-comparative descriptive pilot study evaluating autologous platelet-rich plasma (PRP) injections in adults with persistent (\>6 months) non-tumoural olfactory dysfunction, either age-related degenerative olfactory dysfunction (DOD) or post-traumatic olfactory dysfunction (DOPT). Participants receive three PRP injections over 4 weeks (Day 0, Day 14, Day 28), with follow-up visits at Month 3 and Month 6 after the first injection. Olfactory function is assessed using the Sniffin' Sticks Test (TDI score). Patient-reported outcomes include SNOT-22 and a visual analog scale (VAS) for perceived olfactory impairment. Safety is assessed through adverse event collection.

Conditions

Olfactory Dysfunction; Post-traumatic Olfactory Dysfunction; Age-related Degenerative Olfactory Dysfunction

Keywords

Platelet-rich plasma; PRP; Sniffin' Sticks; Olfactory cleft; Hyposmia; Anosmia

Outcome Measures

Primary Outcomes (1)

• Proportion of participants with clinically meaningful improvement in olfactory function (Sniffin' Sticks Test TDI score)

  Proportion of participants whose change in olfactory function, measured using the Sniffin' Sticks Test (Threshold, Discrimination, Identification score - TDI), between baseline (Visit 1, prior to the first PRP injection) and the 6-month follow-up visit reaches or exceeds the minimal clinically significant difference (MCID) of 5.5 points on the 48-point TDI scale. The TDI score combines three components: olfactory threshold (T), odor discrimination (D), and odor identification (I).

  Baseline (Visit 1, prior to first injection) to Month 6 follow-up (Visit 5)

Secondary Outcomes (5)

• Occurrence of treatment-related adverse events

  From first injection (Day 0) to Month 6 follow-up visit

• Change in olfactory function at Month 3 (TDI score)

  Baseline (Visit 1) to Month 3 follow-up (Visit 4)

• Change in olfactory function at Month 6 (TDI score)

  Baseline (Visit 1) to Month 6 follow-up (Visit 5)

• Change in quality of life (SNOT-22 score)

  Baseline (Visit 1) to Month 6 follow-up (Visit 5)

• Change in patient-reported olfactory impairment (Visual Analog Scale)

  Baseline (Visit 1) to Month 6 follow-up (Visit 5)

Study Arms (1)

PRP injections

EXPERIMENTAL

Single arm receiving autologous platelet-rich plasma injections at Day 0, Day 14 (±1), and Day 28 (±1), with follow-up at Months 3 and 6.

Biological: Autologous Platelet-Rich Plasma (PRP) Injection

Interventions

Autologous Platelet-Rich Plasma (PRP) Injection BIOLOGICAL

At each injection visit (Day 0, Day 14 ±1, Day 28 ±1), venous blood is collected and processed to obtain autologous PRP using a standardized preparation system. PRP is injected under endoscopic guidance into the superior nasal septum mucosa near the olfactory cleft, up to a total volume of 4 mL per visit. Participants are monitored after each injection and adverse events are recorded.

PRP injections

Eligibility Criteria

• Age: 18 Years - 99 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults with persistent (\>6 months) non-tumoural olfactory dysfunction: age-related degenerative olfactory dysfunction (DOD) or post-traumatic olfactory dysfunction (DOPT).
• Objective olfactory impairment confirmed by Sniffin' Sticks Test (TDI ≤ 30.5/48).
• MRI within the last 6 months after onset excluding tumoural etiology or central cause.
• Normal nasal endoscopy.
• Affiliated to a social security system (or equivalent).
• Written informed consent.

You may not qualify if:

• Inflammatory rhinosinus disease (e.g., nasal polyposis) or granulomatosis with polyangiitis.
• Coagulation disorder.
• Brain radiotherapy history or ongoing chemotherapy.
• Olfactory disorder temporally linked to SARS-CoV-2 infection (delay \<1 month).
• History of sinus or skull base surgery (except septoplasty/turbinoplasty/rhinoseptoplasty).
• Therapeutic-dose anticoagulants.
• Refusal to discontinue chronic NSAID use if applicable.
• Pregnancy/labor/breastfeeding.
• Vulnerable persons (deprived of liberty; legal protection; etc.).

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (1)

Hôpital Lyon Sud

Pierre-Bénite, 69310, France

Location

MeSH Terms

Conditions

Anosmia

Interventions

Injections

Condition Hierarchy (Ancestors)

Olfaction Disorders; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Drug Administration Routes; Drug Therapy; Therapeutics

Central Study Contacts

MAxime FIEUX, Dr

CONTACT

0033 4 72 66 64 15; maxime.fieux@chu-lyon.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Single-arm descriptive pilot study with two diagnostic cohorts analyzed separately (DOD and DOPT).

Study Record Dates

• First Submitted: March 11, 2026
• First Posted: March 16, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): May 1, 2028
• Study Completion (Estimated): May 1, 2028
• Last Updated: March 20, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)