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

This prospective, multicenter registry study evaluates the real-world deployment, clinical protection, and safety profile of zamerovimab and mazorelvimab injection (ZM cocktail)- containing two non-overlapping human monoclonal antibodies-in community emergency settings. Rabies presents a near 100% case-fatality rate upon symptom onset, making immediate and high-potency passive immunization essential during the active-vaccine immunity window (Days 0-7). Recent regional epidemic resurgences underscore the public health urgency of handling single-dog multiple-bite clusters, where furious rabid animals carry high viral loads and inflict multiple deep lesions.Approximately 80 patients receiving routine post-exposure care will be enrolled. Participants will receive standard-of-care wound debridement, anatomical infiltration of the ZM cocktail, and a full rabies vaccine regimen. Joining this registry involves no additional clinical interventions beyond standard medical care; investigators will actively maintain follow-up contacts at 3 months and 1 year to document survival outcomes. Concurrently, trapped offending dogs will undergo molecular verification via reverse transcription polymerase chain reaction (RT-PCR) and next-generation sequencing (NGS) to map localized viral ecology, providing crucial real-world data to optimize outbreak emergency response frameworks.

Inclusion criteria

• 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.

Exclusion criteria

• 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.