A NEW rabies vaccine candidate has shown strong and sustained immune responses for up to 1 year after a single dose, alongside a favourable safety profile in both adults and children in Tanzania.
Novel Rabies Vaccine for Pre-Exposure Prophylaxis
Rabies remains a fatal viral disease once symptoms appear, responsible for an estimated 59,000 deaths globally each year, predominantly in low-resource settings where access to vaccination can be limited.
The Phase 1b/2 trial evaluated ChAdOx2 RabG, a viral vector-based vaccine designed to offer low-cost, single-dose pre-exposure protection.
Participants included healthy adults and children in a semi-urban region of Tanzania, with different dosing regimens compared against licensed inactivated rabies vaccines.
Rabies Vaccine Well Tolerated Across Age Groups
The rabies vaccine candidate was generally well tolerated across all dose groups. Reported side effects were mostly mild to moderate, with injection-site pain and feverishness among the most common. No serious vaccine-related adverse reactions were observed during the study period.
These findings support a reassuring safety profile in both adult and paediatric populations, including in dose-escalation and age de-escalation cohorts.
Sustained Antibody Responses After a Single Dose
Immunogenicity results showed that a single full dose of ChAdOx2 RabG generated robust rabies virus neutralising antibody responses that were maintained at 365 days. Antibody levels were significantly higher than those seen in participants receiving a single-visit licensed inactivated rabies vaccine.
In children, immune responses were particularly strong, with higher antibody titres than those observed in adults and comparator vaccine groups. In all ChAdOx2 RabG recipients, antibody levels remained above the accepted threshold associated with protection against rabies infection.
Comparing Rabies Vaccine with Existing Vaccination Approaches
The study also included comparisons with standard inactivated rabies vaccine schedules, including single-visit and two-visit regimens.
The rabies vaccine candidate produced higher sustained antibody levels than the single-visit comparator and, in post-hoc analysis, exceeded responses seen in the two-visit schedule in children.
These findings were observed over a 12-month follow-up period, with longer-term monitoring still ongoing to assess durability beyond 1 year.
Overall, ChAdOx2 RabG could present a promising, cost-effective option for pre-exposure prophylaxis in rabies-endemic areas.
Reference
Ritchie AJ et al. Safety and immunogenicity of a single-dose adenovirus-vectored rabies vaccine over 1 year in adults and children in Tanzania: interim data from an ongoing, partly randomised, controlled, phase 1b/2 trial. Lancet Infect Dis. 2026; DOI:10.1016/S1473-3099(26)00071-X.
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