Seasonal R21 Mass Vaccination for Malaria Elimination (SERVAL)

London School of Hygiene and Tropical Medicine

Status and phase: Enrolling; Phase 3

Conditions: Malaria

Treatments: Biological: R21Matrix M

Study type: Interventional

Funder types: Other

Identifiers

NCT06578572

LEO29834

Details and patient eligibility

About

This is a cluster randomized trial to determine the impact of seasonal R21/MM mass vaccination (all ages) on malaria transmission and morbidity. Fifty-four villages (30 in The Gambia and 24 in Burkina Faso) will be randomized to either mass vaccination with R21 or no mass vaccination.

The primary objective is to compare in intervention and control clusters the prevalence of malaria (all age groups) at peak transmission after seasonal mass vaccination with R21 (3 monthly doses).

Secondary objectives are:

1. To assess the safety and tolerability of R21 through spontaneously reported adverse events.
2. To compare in intervention and control clusters the incidence of malaria infection (all age groups) during the malaria transmission season following seasonal mass vaccination with R21 (3 monthly doses).
3. To compare in intervention and control clusters the incidence of clinical malaria (all age groups) after seasonal mass vaccination with R21 (3 monthly doses).
4. To compare in intervention and control clusters the prevalence of malaria (all age groups) at peak transmission after one booster dose of R21.
5. To compare in intervention and control clusters the incidence of malaria infection (all age groups) during the malaria transmission season following one booster dose of R21.
6. To compare in intervention and control clusters the incidence of clinical malaria (all age groups), after one booster dose of R21.
7. To determine the coverage of seasonal mass vaccination with R21 (primary series of three vaccinations and booster) in intervention clusters and related socio-cultural factors
8. To estimate the cost of seasonal mass vaccination with R21 administration.
9. To estimate the cost-effectiveness of seasonal mass vaccination with R21 compared to standard malaria control measures.

The exploratory objective is to determine whether serological markers can detect changes in malaria transmission following mass vaccination with R21.

Full description

This is a cluster-randomized controlled trial. Fifty-four villages (30 in The Gambia and 24 in Burkina Faso) will be randomized to either mass vaccination with R21 or no mass vaccination. Therefore,15 medium-sized (200-600 people) villages in The Gambia and 12 medium-sized (200-600 people) villages in Burkina Faso will receive the intervention. All study villages will receive standard control intervention, e.g., seasonal malaria chemoprevention, insecticide-treated bed nets, implemented by the National Malaria Control Program and according the National Strategic Plan for malaria control. Mass vaccination will be completed before the start of the malaria transmission season, i.e. July.

A cross-sectional survey to estimate malaria prevalence will be implemented at peak transmission, both following the mass vaccination with 3 doses (first year) and the booster dose (second year). A blood sample will be collected during the malaria transmission season from a cohort of randomly selected individuals to determine the incidence of malaria infection. A system of passive case detection to determine the incidence of clinical malaria will be set up throughout the study period, with special attention to the malaria transmission season (July-December).

Enrollment: 16,200 estimated patients

Sex: All

Ages: 5 months to 99 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Age≥ 5 months.
2. Willingness to comply with trial procedures.
3. Individual written informed consent obtained at the beginning of the study.

Exclusion criteria

1. Pregnancy
2. History of allergic disease or reactions likely to be exacerbated by any component of the vaccines, e.g., Kathon, neomycin, betapropiolactone.
3. Any history of anaphylaxis in relation to vaccination.
4. Known chronic illness.
5. 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.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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16,200 participants in 2 patient groups

Experimental Group

Experimental group

Description:

Three monthly doses of R21/MM will be administered to all eligible residents in the 27 intervention villages (15 in The Gambia and 12 in Burkina Faso), starting from May 2024, with the aim of having completed the vaccination schedule by end of July 2024, before the malaria transmission season starts. A booster vaccine dose will be administered in June 2025 to all eligible individuals who received at least one vaccine dose the previous year. Residents who are eligible but not vaccinated in the previous year, will be offered a complete vaccination schedule, i.e. 3 monthly doses, starting from April. After each vaccination, the first 100 vaccinated individuals will be visited at home daily, for 3 consecutive days, and then at day 7 after the vaccination to collect local and systemic adverse events (AE). Vaccinated individuals (or their parents) will be asked to report to the nurse based in their study village any illness occurring during the 28 days after vaccination.

Treatment:

Biological: R21Matrix M

Control Group

No Intervention group

Description:

Only standard malaria control measures ( Malaria Chemoprevention (SMC), Intermittent Preventive Treatment during pregnancy (IPTp), Insecticide-Treated bed Nets (ITN), prompt diagnosis and treatment of patients with uncomplicated malaria and Indoor Residual Spraying (IRS)) will be implemented in control villages.