Randomized Clinical Trial of Intranasal Injection of Platelet-Rich Plasma for Treatment of Parosmia

Stanford University

Status: Enrolling

Conditions: Paraosmia

Treatments: Other: Saline; Other: Platelet-rich Plasma (PRP)

Study type: Interventional

Funder types: Other

Identifiers

NCT06283745

73225

Details and patient eligibility

About

This randomized clinical trial will evaluate the benefit of platelet-rich plasma (PRP) in the treatment of qualitative olfactory dysfunction (parosmia). PRP can be isolated from a patient's own blood and has been found in previous studies to have anti-inflammatory and pro-regenerative properties. It has been used across multiple specialties, such as Orthopedics, Facial Plastics, Dermatology, Neurology in injected form to treat a wide variety of tissues to encourage the body's inherent regenerative capacity. The investigators have completed a randomized controlled trial here, ending in 2022, evaluating it's use in post-SARS-CoV-2 olfactory loss which demonstrated safety and efficacy. Therefore, the investigators aim to assess the ability of PRP to improve olfactory function in patients with parosmia.

Enrollment: 40 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients >= 18 years of age
• Patients who have qualitative olfactory distortion
• Etiology of qualitative olfactory distortion is due to upper respiratory infection
• Quantitative score under the 10th percentile on the SSParoT (HedRang and HedDir)
• Quantitative score ≥ 8 on the QOD.
• At least 6 months of parosmia but less than 24 months
• Patients can have been previously treated with oral and topical steroids but this is not a requirement
• Patients will receive concurrent olfactory training - the practice of smelling strong odors (standard of care)
• Be able to read and understand English
• Be able and willing to provide Informed Consent

Exclusion criteria

• Patients < 18 years of age, pregnant females, patients who have structural abnormalities on nasal endoscopy or radiographic imaging that would prevent injection into the olfactory cleft
• Olfactory loss due to trauma, chronic sinusitis / inflammation / polyps, neoplasms, or neurodegenerative diseases or patients who have had olfactory loss > 24 months
• Patients with bleeding disorders or on blood thinners such as coumadin and plavix

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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40 participants in 2 patient groups

Platelet Rich Plasma (PRP)

Active Comparator group

Description:

Participants receive PRP intranasal injection into the olfactory cleft three times, separated by two weeks each. Blood is drawn from the patient. This is placed in a centrifuge and using a specialized PRP kit (Emcyte), the sequential spinning process isolates the platelet-rich plasma portion of the blood and we inject that back into the patient within the nasal cavity.

Treatment:

Other: Platelet-rich Plasma (PRP)

Saline

Active Comparator group

Description:

Participants receive saline injections into the olfactory cleft three times, separated by two weeks each. (Sham/placebo injections).

Treatment:

Other: Saline