Study on the Safety and Efficacy of Intratympanic Injection of Small Extracellular Vesicles Derived From Mesenchymal Stem Cells in Severe and Profound Sudden Sensorineural Hearing Loss

NCT07404709 | Not Yet Recruiting Phase 1 DMC

• 1 other identifier: QYFYEC2025-196
• Study Type: interventional
• Target: 9
• Locations: 1 country
• Sites: 5

Brief Summary

The goal of this clinical trial is to learn if small extracellular vesicles derived from mesenchymal stem cells work to treat severe and above sudden sensorineural hearing loss. It will also learn about the safety of small extracellular vesicles. The main questions it aims to answer are:

1. 1.Does small extracellular vesicles combined with traditional drug treatment improve hearing even better in severe and above sudden deafness participants?
2. 2.What medical problems do participants have with intratympanic injection of small extracellular vesicles? Researchers will compare small extracellular vesicles to dexamethasone to see if small extracellular vesicles work to treat severe and above sudden sensorineural hearing loss.
3. 3.Receive traditional drug treatment in accordance with the "Guidelines for the Diagnosis and Treatment of Sudden Deafness (2015)
4. 4.Receive small extracellular vesicles or a placebo tympanic injection additionally
5. 5.Visit the clinic once every 2 weeks for checkups and tests
6. 6.Receive tympanic injections of small extracellular vesicles ranging from low concentration to high concentration
7. 7.Be evaluated for any adverse reactions In clinical Phase II trial, participants were randomly divided into a control group and an experimental group.
8. 8.Received intratympanic injections of small extracellular vesicles 3 times together with traditional drug treatment in experimental group
9. 9.Received intratympanic injections of 5mg dexamethasone 3 times together with traditional drug treatment in control group, also for a total of 3 times Visit the clinic once 7 days , 1month and 3 months after treatment for checkups and tests of pure tone audiometry, speech audiometry, tinnitus disability scale and visual analogue scale assessment

Conditions

Sudden Hearing Loss; Extracellular Vesicles

Outcome Measures

Primary Outcomes (2)

• Pure tone test

  The hearing recovery status is evaluated based on the changes in pure tone threshold from the baseline at enrollment to 3 months of follow-up. The pure tone threshold is the average of air conduction thresholds at 0.25, 0.5, 1, 2, 4 kHz, and 8 kHz.

  Baseline,7 days,1 month, and 3 months after clinical phase II treatment

• speech audiometry

  The hearing recovery status is also evaluated based on the changes in speech recognition rate from the baseline at enrollment to 3 months of follow-up. The speech audiometry results use the speech recognition rates at the baseline and after treatment of the subjects.

  Baseline,7 days,1 month, and 3 months after clinical phase II treatment

Secondary Outcomes (9)

• Respiration

  Baseline, 2 weeks after intratympanic injection in the first-phase clinical

• Heart rate

  Baseline, 2 weeks after intratympanic injection in the first-phase clinical

• Oxygen saturation

  Baseline, 2 weeks after intratympanic injection in the first-phase clinical

• Blood pressure

  Baseline, 2 weeks after intratympanic injection in the first-phase clinical

• tympanic membrane healing status

  Baseline, 2 weeks after intratympanic injection in the first-phase clinical

Study Arms (5)

Low-dose Treatment group-Clinical Phase I

EXPERIMENTAL

Standard treatment for sudden deafness+hUC-MSC-sEV-003 at low-dose treatment in clinical phase I

Drug: Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at low doses

Moderate-dose Treatment Group--Clinical Phase I

EXPERIMENTAL

Standard treatment for sudden deafness+hUC-MSC-sEV-003 at moderate-dose treatment in clincal phase I

Drug: Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at moderate doses

High-dose treatment in Clincal Phase I

EXPERIMENTAL

Standard treatment for sudden deafness+hUC-MSC-sEV-003 at high-dose treatment in clincal phase I

Drug: Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at high doses

Treatment Group--Clinical Phase II

EXPERIMENTAL

Standard treatment for sudden deafness+hUC-MSC-sEV-003 at an appropriate dose as determined by the stage I trial

Drug: Standard treatment for sudden deafness+hUC-MSC-sEV-003 at an appropriate dose as determined by stage I trial

Control Group--Clinical Phase II

ACTIVE COMPARATOR

Standard treatment for sudden deafness+dexamethasone injected into the tympanic cavity

Drug: Standard treatment for sudden deafness+dexamethasone

Interventions

Standard treatment for sudden deafness+hUC-MSC-sEV-003 at an appropriate dose as determined by stage I trial DRUG

After the safety verification and dose determination of the Phase I clinical trial were completed, about 20 participants received standard treatment in accordance with the "Guidelines for the Diagnosis and Treatment of Sudden Deafness (2015)", and at the same time, they were administered intratympanic injections of small extracellular vesicles every other day, for a total of 3 times.

Treatment Group--Clinical Phase II

Standard treatment for sudden deafness+dexamethasone DRUG

Participants in the control group received standard treatment in accordance with the "Guidelines for the Diagnosis and Treatment of Sudden Deafness (2015)", and during their hospitalization, they received intratympanic injections of dexamethasone at a dose of 5mg every other day for a total of 3 times.

Control Group--Clinical Phase II

Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at low doses DRUG

In Clinical Phase I, three participants were first injected with small extracellular vesicles at low doses (2×108particles/mL) together with traditional drug treatment. The intratympanic injection of small extracellular vesicles was given every other day for a total of 3 times for every participants.

Low-dose Treatment group-Clinical Phase I

Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at moderate doses DRUG

In Clinical Phase I, if no adverse reactions were observed for 2 weeks after the low-dose group was injected, three participants were then injected with small extracellular vesicles at moderat doses (1×109particles/mL) together with traditional drug treatment. The intratympanic injection of small extracellular vesicles was given every other day for a total of 3 times for every participants.

Moderate-dose Treatment Group--Clinical Phase I

Tympanic injection of hUC-MSC-sEV-003 (small extracellular vesicles) at high doses DRUG

n Clinical Phase I, if no adverse reactions were observed for 2 weeks after the moderate-dose group was injected, three participants were then injected with small extracellular vesicles at high doses (5×109particles/mL) together with traditional drug treatment. The intratympanic injection of small extracellular vesicles was given every other day for a total of 3 times for every participants.

High-dose treatment in Clincal Phase I

Eligibility Criteria

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

You may qualify if:

• Sudden unilateral hearing loss that occurs within 72 hours, with a decrease of at least 30 decibels in at least 3 frequency ranges compared to the healthy ear, and an average pure tone threshold of ≥ 65 decibels.
• Enrollment must be completed within 7 days after the onset of sudden deafness.
• Men or women aged 18 to 65
• Not treated in any other hospital and not taking any treatment medication on one's own
• Be able to understand the trial protocol and undergo regular follow-up visits and check-ups

You may not qualify if:

• Pregnant or lactating women
• With a history of chronic ear diseases, ear surgery, autoimmune hearing loss or a confirmed diagnosis of Meniere's syndrome in the past
• Having received steroid treatment for any reason within the past 30 days
• There are autoimmune diseases or chronic inflammatory diseases.
• Severe damage to liver and kidney functions
• Patients with a previous history of cerebral hemorrhage or those currently taking anticoagulant medications

Sponsors & Collaborators

• The Affiliated Hospital of Qingdao University: lead

Study Sites (5)

The First Affiliated Hospital of Sun Yat-sen University

Guangzhou, Guangdong, 510080, China

Location

Guangdong General Hospital

Guangzhou, Guangdong, 519041, China

Location

The Affiliated Hospital of Qingdao University

Qingdao, Shandong, 266100, China

Location

he Second Affiliated Hospital of Shandong First Medical University

Tai’an, Shandong, 271000, China

Location

Chongqing General Hospital

Chongqing, Sichuan, 401121, China

Location

MeSH Terms

Conditions

Hearing Loss, Sudden

Condition Hierarchy (Ancestors)

Hearing Loss; Hearing Disorders; Ear Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Yan Jiang

CONTACT

+86-532-82915920; jiangyanoto@qdu.edu.cn

Caili Ji

CONTACT

+86-532-82915920; haidecai@163.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Chief Physician

Study Record Dates

• First Submitted: December 23, 2025
• First Posted: February 11, 2026
• Study Start: February 28, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2028
• Last Updated: March 25, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

CN (5)