Safety and Immunogenicity of Coadministration of the Candidate Rabies Vaccine ChAdOx2 RabG and Licensed Vaccine

NCT07168018 | Not Yet Recruiting Phase 2 DMC

• 1 other identifier: RAB003
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

This is a phase II randomised, open-label study to assess the safety and immunogenicity of coadministration of the candidate rabies vaccine ChAdOx2 RabG and licensed vaccine in healthy adults (18-45 years old). ChAdOx2 RabG will be administered intramuscularly and licensed rabies vaccine will be given either intramuscularly (i.e., for the intervention group) or by intradermal injection (i.e., for the control group).

Conditions

Rabies

Keywords

Vaccine

Outcome Measures

Primary Outcomes (4)

• Safety and tolerability of coadministration of ChAdOx2 RabG and inactivated rabies vaccine (IRV) in healthy adults (18-45 years) residing in a rabies endemic country by the occurrence of solicited adverse events.

  Occurrence of local and systemic solicited AEs

  Assessment of solicited AEs in the first 7 days post vaccination

• Safety and tolerability of coadministration of ChAdOx2 RabG and inactivated rabies vaccine (IRV) in healthy adults (18-45 years) residing in a rabies endemic country by the occurrence of unsolicited adverse events.

  Occurrence of unsolicited local and systemic adverse events

  Unsolicited AEs to be assessed up to 28 days post vaccination

• Safety and tolerability of coadministration of ChAdOx2 RabG and inactivated rabies vaccine (IRV) in healthy adults (18-45 years) residing in a rabies endemic country by the occurrence of laboratory adverse events.

  Occurrence of laboratory adverse events.

  Clinical laboratory AEs to be assessed up to 28 days post vaccination.

• Safety and tolerability of coadministration of ChAdOx2 RabG and inactivated rabies vaccine (IRV) in healthy adults (18-45 years) residing in a rabies endemic country by the occurrence of serious adverse events.

  Occurrence of serious adverse events

  SAEs will be collected from enrolment until the end of the follow-up period (Day 56).

Secondary Outcomes (1)

• A comparison of the immunogenicity of a singe-visit IM coadministration of ChAdOx2 RabG and licensed IRV versus three-visit ID administration of licensed IRV.

  Rabies virus neutralisation antibody titres will be determined at baseline and days 7, 14, 21, 28, and 56.

Study Arms (2)

Group A1 (Adults)

EXPERIMENTAL

Participants aged 18-45 years will receive coadministration of 5×10\^10 vp ChAdOx2 RabG (2 site IM) and licensed IRV (2 site IM) at a single visit. Rabies virus neutralisation antibody (VNA) titres will be determined at baseline and days 7, 14, 21, 28, and 56. Participants will receive a 1-site IM vaccination with IRV on day 56.

Biological: Coadministration of ChAdOx2 RabG and licensed inactivated rabies vaccine (IRV)

Group A2 (Adults)

ACTIVE COMPARATOR

Participants aged 18-45 years will receive a licensed IRV (2 site ID) at days 0, 3 and 7. Rabies virus neutralisation antibody (VNA) titres will be determined at baseline and days 7, 14, 21, 28, and 56.

Biological: Inactivated Rabies Vaccine (IRV)

Interventions

Coadministration of ChAdOx2 RabG and licensed inactivated rabies vaccine (IRV) BIOLOGICAL

A single visit of coadministration of 5×10\^10 vp ChAdOx2 RabG (2 site IM) and licensed IRV (2 site IM).

Group A1 (Adults)

Inactivated Rabies Vaccine (IRV) BIOLOGICAL

A World Health Organization (WHO) prequalified IRV at two anatomical sites (2 site ID) on days 0, 3 and 7.

Also known as: Verorab

Group A2 (Adults)

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy male or female adults aged 18-45 years at the time of enrolment with signed consent.
• (Female only participants): Must be non-pregnant (as demonstrated by a negative serum pregnancy test) and willing to use an effective form of contraception.
• \*Female volunteers are required to use an effective form of contraception during the course of the study. There is currently no information about the effect of this vaccine on a foetus. Acceptable forms of contraception for female volunteers include:
• Established use of injected or implanted hormonal methods of contraception.
• Placement of an intrauterine device (IUD) or intrauterine system (IUS).
• Total abdominal hysterectomy.
• Planned long-term (at least 2 months from the date of the first vaccination) or permanent residence in Bagamoyo town.
• Adults with a Body Mass Index (BMI) 18 to 30 Kg/m2
• Correctly answer all 10 questions on the protocol and study procedures understanding questionnaire within 2 attempts.

You may not qualify if:

• Clinically significant congenital abnormalities as judged by the PI or other delegated individual.
• Clinically significant history of skin disorder, allergy, cardiovascular disease, respiratory disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease and neurological illness which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study or impair interpretation of the study data as judged by the PI or other delegated individual.
• Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed).
• History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ).
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccines, including IRVs e.g. amphotericin B, chlortetracycline, neomycin, polymyxin, streptomycin
• Any history of anaphylaxis in relation to vaccination.
• Clinically significant laboratory abnormality as judged by the PI or other delegated individual.
• Receipt of any previous rabies vaccinations, including an incomplete course of IRV and/or any doses of ChAdOx2 RabG.
• History of vaccination with previous adenoviral vectored vaccines in the 6 months prior to enrolment in the study, or of vaccination with any other vaccine (including non-adenovirus-vectored COVID-19 vaccines) in the 28 days prior to enrolment.
• Planned / likely receipt of any other vaccine within 28 days after enrolment.
• History of bleeding disorder (e.g., factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture, or continuous anticoagulation e.g., with warfarin
• History of confirmed major thrombotic event, (including cerebral venous sinus thrombosis, deep vein thrombosis, pulmonary embolism) or,
• History of antiphospholipid syndrome.
• History of prior receipt of unfractionated heparin
• History of heparin induced thrombocytopenia

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (1)

Ifakara Health Institute

Bagamoyo, Tanzania

Location

MeSH Terms

Conditions

Rabies

Condition Hierarchy (Ancestors)

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

Study Officials

• Alexander D Douglas

  Jenner Institute, University of Oxford

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Paschal Apanga

CONTACT

+441865 617624; paschal.apanga@ndm.ox.ac.uk

Adam Ritchie

CONTACT

+441865 617624; adam.ritchie@ndm.ox.ac.uk

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 4, 2025
• First Posted: September 11, 2025
• Study Start: December 1, 2025
• Primary Completion: March 1, 2026
• Study Completion: March 1, 2026
• Last Updated: November 18, 2025

Record last verified: 2025-10

Locations

TA (1)