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A Study to Assess the Experimental Malaria Vaccines RH5.2-VLP and R21

A Phase Ib Multi-stage Plasmodium Falciparum Malaria Vaccine Study to Assess the Safety and Immunogenicity of the Blood-stage Vaccine Candidate RH5.2 Virus-like Particle (VLP) in Matrix-M and the Pre-erythrocytic Stage Vaccine Candidate R21 in Matrix-M, Both Alone and in Combination, in Adults and Infants in the Gambia

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05357560
Enrollment
107
Registered
2022-05-03
Start date
2023-07-10
Completion date
2025-12-11
Last updated
2026-05-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Malaria, Plasmodium Falciparum

Keywords

RH5.2 virus-like particle (VLP), Matrix-M, R21

Brief summary

This is a Phase Ib multi-stage Plasmodium falciparum malaria vaccine study to assess the safety and immunogenicity of the blood-stage vaccine candidate RH5.2 virus-like particle (VLP) in Matrix-MTM and the pre-erythrocytic stage vaccine candidate R21 in Matrix-MTM, both alone and in combination, in adults and infants in the Gambia

Detailed description

A total of 96 volunteers will be enrolled. Adults (18-45 years) will be enrolled into groups 3 -5. Infants (5 -17 months) will be enrolled into groups 1-2 and groups 6-9. All volunteers will be given 3 doses 50 µg of Matrix-M in combination with RH5.2 VLP and/or R21 via intramuscular (IM) injection in the deltoid region of the non-dominant arm for adults and anterolateral thigh for infants. The first 2 doses will be given at months 0 and 1. Groups 2-6 and group 8 will be given the third dose at month 2, and groups 1, 7 and 9 will be given the third dose at month 6.

Interventions

BIOLOGICALMatrix-M with RH5.2 VLP and/or R21

3 doses of 50 µg of Matrix-M in combination with RH5.2 VLP and/or R21 at different doses and at different timepoints

Sponsors

University of Oxford
Lead SponsorOTHER
European and Developing Countries Clinical Trials Partnership (EDCTP)
CollaboratorOTHER_GOV
Medical Research Council Unit, The Gambia
CollaboratorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
5 Months to 45 Years
Healthy volunteers
Yes

Inclusion criteria

* Groups 1, 2 and 6-9: Healthy male or female infants aged 5-17 months at the time of enrolment with signed consent obtained from parents or guardians. * Groups 3-5: Healthy male or female adults aged 18-45 years at the time of enrolment with signed consent. * Groups 3-5 (Female participants only): Must be non-pregnant (as demonstrated by a negative urine pregnancy test), and practice continuous effective contraception for the 24 to 30 month duration of the study (see section 9.9). * Planned long-term (at least 24 months from the date of recruitment) or permanent residence in the study area. * Adults with a Body Mass Index (BMI) 18 to 30 Kg/m2; or infants with Z-score of weight-for-age within ±2SD.

Exclusion criteria

* Clinically significant congenital abnormalities as judged by the PI or other delegated individual * Clinically significant history of skin disorder (psoriasis, contact dermatitis etc.), allergy, cardiovascular disease, respiratory disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease and neurological illness 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, e.g., Kathon, neomycin, betapropiolactone. * Any history of anaphylaxis in relation to vaccination. * 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 30 days preceding enrolment, or planned receipt of any other vaccine within 30 days following each study vaccination. This excludes COVID-19 vaccines, which should not be received between 14 days before to 7 days after any study vaccination, and EPI vaccines (for infants), which should not be received between 14 days before to 28 days after any study vaccination. * History of vaccination with previous malaria vaccines * Participation in another research study involving receipt of an investigational product in the 30 days preceding enrolment in adults or at any time for infants, or planned use during the study period. * Suspected or known current alcohol abuse. * Suspected or known injecting drug abuse in the 5 years preceding enrolment. * Seropositive for hepatitis B surface antigen (HBsAg), hepatitis C (HCV IgG) or HIV. For infants, any history of vertical exposure to HIV infection. * Any other finding which in the opinion of the PI or other delegated individual would increase the risk of an adverse outcome from participation in the trial. * Positive malaria by PCR screening. * 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. * Any other 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

Design outcomes

Primary

MeasureTime frameDescription
Assessment of safety and tolerability of RH5.2-VLP with Matrix-M and R21 with Matrix-M, in healthy adults and infants assessed through the number of participants with serious adverse eventsWhole duration of the study (24-30 months following initial trial vaccination)Occurrence of serious adverse events including grading of causality
To determine safety and tolerability of RH5.2-VLP with Matrix-M and R21 with Matrix-M, in healthy adults and infants by assessing the occurrence of solicited local reactogenicity signs and symptoms via clinic and home visits7 days following each vaccinationOccurrence of solicited local reactogenicity signs and symptoms via clinic and home visits
To determine safety and tolerability of RH5.2-VLP with Matrix-M and R21 with Matrix-M, in healthy adults and infants by assessing the occurrence of solicited systemic reactogenicity signs and symptoms via clinic and home visits7 days following each vaccinationOccurrence of solicited systemic reactogenicity signs and symptoms via clinic and home visits
To determine safety and tolerability of RH5.2-VLP with Matrix-M and R21 with Matrix-M, in healthy adults and infants by assessing occurrence of unsolicited adverse events28 days following the vaccinationOccurrence of unsolicited adverse events via clinical review, clinical examination (including observations) and laboratory results
Safety of the RH5.2-VLP with Matrix-M and R21 with Matrix-M vaccine, assessed through the number of participants with abnormal laboratory test results28 days following the vaccinationOccurrence of change from baseline laboratory test results

Secondary

MeasureTime frameDescription
To assess the humoral and cellular immunogenicity of RH5.2-VLP and R21 with Matrix-M, performing ELISA at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)Hepatitis B serology, blood samples taken at a number of key timepoints performing ELISA at specified timepoints
To assess the humoral and cellular immunogenicity of RH5.2-VLP with Matrix-M when administered to healthy volunteers at different doses and combinations and used in various regimensLikely at V3+14 or V3+28Growth Inhibition Activity (GIA) (participants vaccinated with RH5.2-VLP only) performed at peak of response after the third vaccination, based on previous work this is likely to be at V3+14 or V3+28
To assess the humoral and cellular immunogenicity of RH5.2-VLP with Matrix-M as assessed by magnitude assessment at various timepointFrom a number of key timepoints, baseline up to day 912 (dependant on group)RH5 serology (participants vaccinated with RH5.2-VLP only), blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for magnitude assessment, late timepoints used to assess longevity of response
To assess the humoral and cellular immunogenicity of RH5.2-VLP with Matrix-M as assessed by antibody kinetics at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)RH5 serology (participants vaccinated with RH5.2-VLP only), blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for antibody kinetics, late timepoints used to assess longevity of response
To assess the humoral and cellular immunogenicity of RH5.2-VLP with Matrix-M, performing ELISA at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)RH5 serology (participants vaccinated with RH5.2-VLP only), blood samples taken at a number of key timepoints performing ELISA at specified timepoints
To assess the humoral and cellular immunogenicity of R21 with Matrix-M performing ELISA at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)R21 serology (participants vaccinated with R21 only), blood samples taken at a number of key timepoints performing ELISA at specified timepoints
To assess the humoral and cellular immunogenicity of R21 with Matrix-M when administered to healthy volunteers at different doses and combinations and used in various regimensFrom a number of key timepoints, base line up to day 912 (dependant on group)Inhibition of sporozoite invasion assay (ISI) (participants vaccinated with R21 only), blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for antibody kinetics and magnitude assessment, and late timepoints to assess longevity of response, performing ELISA at every timepoint where 'immunology serum' is required
To assess the humoral and cellular immunogenicity of R21 with Matrix-M as assessed by antibody kinetics at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)R21 serology (participants vaccinated with R21 only), blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for antibody kinetics, late timepoints used to assess longevity of response
To assess the humoral and cellular immunogenicity of R21 with Matrix-M as assessed by magnitude assessment at various timepointFrom a number of key timepoints, baseline up to day 912 (dependant on group)R21 serology (participants vaccinated with R21 only), blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for magnitude assessment, late timepoints used to assess longevity of response
To assess the humoral and cellular immunogenicity of RH5.2-VLP and R21 with Matrix-M as assessed by antibody kinetics at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)Hepatitis B serology, blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for antibody kinetics, late timepoints used to assess longevity of response
To assess the humoral and cellular immunogenicity of RH5.2-VLP and R21 with Matrix-M as assessed by magnitude assessment at various timepointsFrom a number of key timepoints, baseline up to day 912 (dependant on group)Hepatitis B serology, blood samples taken at a number of key timepoints including baseline and post vaccination of V+7 (adults only), V+14, V+28 to allow for magnitude assessment, and late timepoints to assess longevity of response

Countries

The Gambia

Contacts

PRINCIPAL_INVESTIGATORUmberto D'Alessandro

Medical Research Council Unit, The Gambia

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 13, 2026