A Study to Assess the Experimental Malaria Vaccines R78C and RH5.1 Combined With R21/Matrix-M (a "Multi-stage" Malaria Vaccine) (VAC093)

March 9, 2026 updated by: University of Oxford

A Phase Ib Age De-escalation, Open Label Study of the Safety and Immunogenicity of the Multi-stage Malaria Vaccine Candidate R21 + RH5.1 + R78C in Matrix-M™ in Adults Aged 18-35 Years and Children Aged 5-17 Months in Burkina Faso

This is a Phase Ib age de-escalation, dose escalation, open-label study to assess the safety and immunogenicity of the multi-stage malaria vaccine candidate R21 plus RH5.1 and/or R78C in Matrix-M in adults aged 18-35 years and children aged 5-17 months in Burkina Faso.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

There will be six study groups. Group 1 will consist of 8 adults who will receive three doses of 5 µg R21 + 10 µg RH5.1 + 10 µg R78C. Group 2 will consist of 8 children who will receive three doses of 5 µg R21 + 10 µg RH5.1. Group 3 will consist of 8 children who will receive three doses of 5 µg R21 + 10 µg R78C. Group 4 will consist of 8 children who will receive three doses of 5 µg R21 + 10 µg RH5.1 +10 µg R78C. Group 5 will consist of 8 children who will receive three doses of 5 µg R21. Group 6 will consist of 16 children who will receive three doses of 10 µg RH5.1 +10 µg R78C. All vaccinations will be given in 50 µg Matrix-M. All groups will receive their vaccinations in a 0-1-6 month regimen.

Groups 1 to 4 and 6 will be recruited in a staggered process. There will be a DSMB review prior to age deescalation. There will also be three sentinel participants per group and DSMB reviews prior to each subsequent (second and third) vaccination. Group 5 can be recruited at any time and without need for sentinel participants or DSMB review.

Study Type

Interventional

Enrollment (Estimated)

56

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

  • Name: Angela Minassian, Honorary Consultant and CI

Study Locations

  • Burkina Faso
    • Boulkiemdé Province
      • Siglé, Boulkiemdé Province, Burkina Faso, BP 7192 OUAGADOUGOU 03, BF
        • Recruiting
        • Institut de Recherche en Sciences de la Santé
        • Sub-Investigator:
          • Dr Ousmane Traoré
        • Sub-Investigator:
          • Dr Salou Diallo
        • Sub-Investigator:
          • Dr Toussaint Rouamba
        • Contact:
          • Dr Athanase M. Somé, Doctorat en médecine
          • Phone Number: Ext. +266 25446249
          • Email: athanasesome@crun.bf
        • Principal Investigator:
          • Prof. Halidou Tinto

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

Only participants who meet all the inclusion criteria will be enrolled into the trial:

  • Group 1: Healthy adult aged 18-35 years at the time of first study vaccination
  • Group 2-6: Healthy child aged 5-17 months at the time of first study vaccination
  • Group 1: Female participants must be non-pregnant (as demonstrated by a negative urine pregnancy .

test), and practice continuous effective contraception until three months after the final study vaccination

  • Participant or parent/guardian provides signed/thumb-printed informed consent
  • Participant (and parent/guardian for child participants) resident in the study area villages, and anticipated to be available for vaccination and the duration of follow-up -

Exclusion Criteria:

  • The participant may not enter the trial if ANY of the following apply:

    • Clinically significant congenital abnormalities as judged by the PI or other delegated individual.
    • Clinically significant skin disorder (psoriasis, contact dermatitis, etc.), cardiovascular disease, respiratory disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease, neurological illness as judged by the PI or other delegated individual.
    • History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ).
    • Children with weight-for-age Z score of less than -3 or other clinical signs of malnutrition.
    • History of allergic reaction, significant IgE-mediated event, or anaphylaxis to immunisation.
    • History of allergic disease or reactions likely to be exacerbated by any component of the vaccines.
    • Sickle cell disease.
    • Clinically significant laboratory abnormality at grade 2 or above as judged by the PI or other delegated individual.
    • Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccine candidate.
    • Receipt of any vaccine in the 14 days preceding enrolment, or planned receipt of any other vaccine within 28 days following each study vaccination.
    • History of vaccination with any malaria vaccine.
    • Participation in another research study involving receipt of an investigational product in the 30 days preceding enrolment, or planned use during the study period.
    • Suspected or known current alcohol misuse.
    • Suspected or known injecting drug use in the 5 years preceding enrolment.
    • Female participant who is pregnant, lactating or planning pregnancy during the course of the trial.
    • Scheduled elective surgery or other procedures requiring general anaesthesia during the trial.
    • Seropositive for hepatitis B surface antigen (HBsAg), hepatitis C (HCV IgG) or HIV. For children, any history of vertical exposure to HIV infection.
    • 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 (for corticosteroids, this will mean prednisone, or equivalent, ≥ 0.5 mg/kg/day; inhaled and topical steroids are allowed).
    • Any significant disease, disorder or situation which, in the opinion of the Investigator, may either put the participants at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.

Vaccination and re-vaccination exclusion criteria:

The following adverse events associated with vaccine immunisation constitute absolute contraindications to further administration of vaccine. If any of these events occur during the study, the participant must be withdrawn and followed until resolution of the event, as with any adverse event:

  • Anaphylactic reaction following administration of vaccine.
  • Pregnancy.

The following adverse events constitute contraindications to administration of vaccine at that point in time; if any one of these adverse events occurs at the time scheduled for vaccination, the participant may be vaccinated at a later date, or withdrawn at the discretion of the Investigator. The participant must be followed until resolution of the event as with any adverse event:

  • Acute disease at the time of vaccination (acute disease is defined as the presence of a moderate or severe illness with or without fever or symptoms suggestive of possible COVID-19 disease). All vaccines can be administered to persons with a minor illness such as diarrhoea or mild upper respiratory infection without fever, i.e. axillary temperature < 37.5°C.
  • Temperature of >37.5°C (99.5°F) at the time of vaccination.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Group 1(n=8) adults (18-35years)
They will receive three doses of 5 µg R21 + 10 µg RH5.1 + 10 µg R78C, administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: R21
A protein particle comprising recombinant HBsAg fused to the central repeat and the C-terminus of the circumsporozoite protein
Biological: RH5.1
A soluble protein vaccine against the RH5 antigen
Biological: R78C
A soluble RIPR EGF-CyRPA fusion protein vaccine
Biological: Matrix-M™
A saponin-based vaccine adjuvant
Experimental: Group 2 (n=8) Children aged between 5-17months
They will receive three doses of 5 µg R21 + 10 µg RH5.1, administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: R21
A protein particle comprising recombinant HBsAg fused to the central repeat and the C-terminus of the circumsporozoite protein
Biological: RH5.1
A soluble protein vaccine against the RH5 antigen
Biological: Matrix-M™
A saponin-based vaccine adjuvant
Experimental: Group 3 (n=8) children aged between 5-17 months
They will receive three doses of 5 µg R21 + 10 µg R78C, administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: R21
A protein particle comprising recombinant HBsAg fused to the central repeat and the C-terminus of the circumsporozoite protein
Biological: R78C
A soluble RIPR EGF-CyRPA fusion protein vaccine
Biological: Matrix-M™
A saponin-based vaccine adjuvant
Experimental: Group 4 (n=8) Children aged between 5-17 months
They will receive three doses of 5 µg R21 + 10 µg RH5.1 +10 µg R78C , administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: R21
A protein particle comprising recombinant HBsAg fused to the central repeat and the C-terminus of the circumsporozoite protein
Biological: RH5.1
A soluble protein vaccine against the RH5 antigen
Biological: R78C
A soluble RIPR EGF-CyRPA fusion protein vaccine
Biological: Matrix-M™
A saponin-based vaccine adjuvant
Experimental: Group 5 (n=8) children aged 5-17 months
They will receive three doses of 5 µg R21, administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: R21
A protein particle comprising recombinant HBsAg fused to the central repeat and the C-terminus of the circumsporozoite protein
Biological: Matrix-M™
A saponin-based vaccine adjuvant
Experimental: Group 6 ( n=16) Children 5-17 months
They will receive three doses of 10 µg RH5.1 +10 µg R78C, administered at Month 0 (Day 0), Month 1 (Day 28), and Month 6 (Day 182), given as an Intramuscular injection to the deltoid region (adults) or anterolateral thigh (children)
Biological: RH5.1
A soluble protein vaccine against the RH5 antigen
Biological: R78C
A soluble RIPR EGF-CyRPA fusion protein vaccine
Biological: Matrix-M™
A saponin-based vaccine adjuvant

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Safety: To assess the safety and reactogenicity of R21, RH5.1 and R78C in Matrix-M™ when used in different combinations in healthy adults and children living in a malaria-endemic area.
Time Frame: Solicited AEs will be assessed at Day 0, Days 1-6, 28, days 29-34, 182 and days 187. Unsolicited AEs on Day 0, Days 1-6, 14, 28, Days 29-34, 42, 56, 182, Days 183-187 and 196. All SAEs will be assessed throughout the study follow up period upto Day 365

The specific endpoints for safety and reactogenicity will be actively and passively collected data on adverse events. The following parameters will be assessed:

  • Occurrence of solicited local reactogenicity signs and symptoms for 7 days following each vaccination (day of vaccination and 6 subsequent days)
  • Occurrence of solicited systemic reactogenicity signs and symptoms for 7 days following each vaccination (day of vaccination and 6 subsequent days)
  • Occurrence of unsolicited adverse events for 28 days following the vaccination (day of vaccination and 27 subsequent days)
  • Clinically significant change from baseline for safety laboratory measures throughout the study
  • Occurrence of serious adverse events during the whole study duration.
Solicited AEs will be assessed at Day 0, Days 1-6, 28, days 29-34, 182 and days 187. Unsolicited AEs on Day 0, Days 1-6, 14, 28, Days 29-34, 42, 56, 182, Days 183-187 and 196. All SAEs will be assessed throughout the study follow up period upto Day 365

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Immunogenicity: To assess the humoral immunogenicity of R21, RH5.1 and R78C in Matrix-M™ when used in different combinations in healthy adults and children living in a malaria-endemic area.
Time Frame: Immunology blood samples will be collected at screening, day of vaccination, at Days 42, 56, 182, 196, 210, 240, and 365.

Immunogenicity will be assessed by a variety of immunological assays. The following measures will be assessed:

  • Serum response:

    o Quantitative antigen-specific IgG antibody levels (µg/mL readout) over time - analysis of peak responses and longevity;

  • In vitro GIA against 3D7 clone P. falciparum parasites using purified total IgG and a single-cycle pLDH readout assay
Immunology blood samples will be collected at screening, day of vaccination, at Days 42, 56, 182, 196, 210, 240, and 365.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Oxford

Collaborators

Wellcome Trust
European and Developing Countries Clinical Trials Partnership (EDCTP)
Institut de Recherche en Sciences de la Sante, Burkina Faso
European Vaccine Initiative
Bundesministerium für Forschung, Technologie und Raumfahrt (BMFTR)

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 15, 2025

Primary Completion (Estimated)

October 1, 2026

Study Completion (Estimated)

October 1, 2026

Study Registration Dates

First Submitted

April 23, 2025

First Submitted That Met QC Criteria

May 2, 2025

First Posted (Actual)

May 6, 2025

Study Record Updates

Last Update Posted (Actual)

March 11, 2026

Last Update Submitted That Met QC Criteria

March 9, 2026

Last Verified

April 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • VAC093

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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