Real-World Effectiveness of Zamerovimab and Mazorelvimab and Vaccine for Rabies Grade III Exposure in Nanyang

NCT07624461 | Active Not Recruiting FDA Drug

• 1 other identifier: SYN023-RWE-001
• Study Type: observational
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

The objective of this real-world, prospective observational study is to evaluate the clinical effectiveness of zamerovimab and mazorelvimab injection (a human rabies monoclonal antibody cocktail) administered in combination with a standard rabies vaccine for post-exposure prophylaxis (PEP) in individuals with WHO Grade III rabies exposure in Nanyang City, China.

1. 1.The study primarily aims to assess:
2. 2.The 3-month rabies-free survival rate following PEP initiation.
3. 3.The 1-year long-term rabies-free survival rate.

Conditions

Rabies Post-exposure Prophylaxis; Rabies

Keywords

Single-dog Multiple-bite Incidents; Grade III rabies exposures

Outcome Measures

Primary Outcomes (1)

• 3-month rabies-free survival rate

  The proportion of participants alive and free of clinical rabies symptoms at 90 days following post-exposure prophylaxis (PEP) initiation.

  90 days (±3 days) post-enrollment

Secondary Outcomes (1)

• 1-year rabies-free survival rate

  365 days (±7 days) post-enrollment

Study Arms (1)

Grade III rabies exposure cohort

Adults (≥18 years) who sustained verified WHO Grade III rabies exposure from a traceable dog involved in a tracked multi-person attack incident, and who initiated standardized PEP within the protocolized window.

Drug: Zamerovimab and Mazorelvimab Injection plus Rabies Vaccine

Interventions

Zamerovimab and Mazorelvimab Injection plus Rabies Vaccine DRUG

Standard-of-care wound debridement, followed by anatomical infiltration of zamerovimab/mazorelvimab injection at a single dose of 0.3 mg/kg around the wound sites on Day 0, combined with a standard intramuscular rabies vaccine regimen.

Grade III rabies exposure cohort

Eligibility Criteria

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

Study Population

People aged 18 or older who were bitten by a dog that also bit others, have a serious (Grade III) rabies exposure, and already received wound cleaning, the antibody injection, and the first rabies shot within 24 hours can join.

You may qualify if:

• Adults aged ≥18 years at the time of screening.
• Sustained a verified WHO Grade III rabies exposure from a traceable offending dog involved in a multi-person canine attack incident (defined as a single animal attacking multiple individuals within a clustered timeframe/location) in Nanyang City.
• Time interval from Grade III exposure to post-exposure prophylaxis (PEP) initiation is less than 7 days.
• Successfully completed standard wound debridement, anatomical infiltration of zamerovimab/mazorelvimab injection (0.3 mg/kg single full dose), and the first dose of rabies vaccine within 24 hours prior to screening.
• Voluntarily provides signed written informed consent.
• Patient is willing and able to comply with all sequential follow-up procedures (including serum collections if applicable) and intends to reside locally for the full 1-year study duration.

You may not qualify if:

• Documented history of any separate animal bite or scratch (e.g., dog, cat, bat, or wild carnivore) within the past 12 months prior to the current exposure.
• Documented complete pre-exposure or post-exposure rabies vaccination history within the past 12 months.
• Concurrent presentation with life-threatening traumatic injuries requiring intensive care, or severe systemic immunodeficiency disorders that could impede immunogenicity or follow-up compliance.
• Any other clinical or psychological condition deemed by the investigator as unsuitable for safe participation or reliable data registry.

Sponsors & Collaborators

• Synermore Biologics (Suzhou) Co., Ltd.: lead

Study Sites (1)

The Disease Prevention and Control Center of Nanyang

Nanyang, Henan, 473000, China

Location

MeSH Terms

Conditions

Rabies

Interventions

Rabies Vaccines

Condition Hierarchy (Ancestors)

Rhabdoviridae Infections; Mononegavirales Infections; RNA Virus Infections; Virus Diseases; Infections

Intervention Hierarchy (Ancestors)

Viral Vaccines; Vaccines; Biological Products; Complex Mixtures

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Year
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 28, 2026
• First Posted: June 3, 2026
• Study Start: June 6, 2025
• Primary Completion: March 31, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: June 11, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)