R21/MM Dosing, Presentations, and Preservatives

NCT07194668 | Not Yet Recruiting Phase 4 DMC

• 1 other identifier: MAL25005
• Study Type: interventional
• Target: 375
• Locations: 1 country
• Sites: 2

Brief Summary

This is a single blind randomised controlled trial (Phase 3 trial). This study aims to assess whether a half-dose of the R21/Matrix-M malaria vaccine is as effective as the full dose in children and adults. The results will help optimize vaccine usage and improve malaria prevention strategies. All participants will receive the same number of injections and will be randomly assigned to receive one of the followings:

• Group 1: Adults and adolescents receiving the standard adult vaccine dose: 10μg R21/50μg Matrix-M (n=125).
• Group 2: Adults and adolescents receiving a half of the standard adult vaccine dose: 5μg R21/50μg Matrix-M: 10 dose vials with adaptor Preservative Free (n=125)
• Group 3: Adults and adolescents receiving a half of the standard adult vaccine dose: 5μg R21/50μg Matrix-M: 10 dose vials with 2PE Preservative (n=125) Clinical procedure for participants:
• Standardized symptom questionnaire
• Physical examination: Weight, height, pulse, blood pressure, respiratory rate, tympanic temperature. Spleen and liver size will be recorded if palpable. Pregnancy test (for female of child bearing potential)
• Venous blood collection (Pre-vaccination) 3mL
• Vaccination

Conditions

Plasmodium Falciparum Malaria; Malaria; Vaccine Reaction

Keywords

Plasmodium Falciparum Malaria; Malaria Vaccine

Outcome Measures

Primary Outcomes (2)

• The concentration of antibodies against Plasmodium falciparum circumsporozoite (anti-NANP total IgG antibody)

  One month after the completion of the third dose (at M3), and one month after the booster dose (at M12).

• The concentration of antibodies against Plasmodium falciparum circumsporozoite (anti C-Term, and full length R21 total IgG antibody), in addition to total IgG against Hepatitis B surface antigen

  One month after the completion of the third dose (at M3), and one month after the booster dose (at M12).

Secondary Outcomes (2)

• Adverse event and severe adverse event reports for safety and tolerability assessment of the standard adult vaccine dose 10μg R21/50μg Matrix-M and a half of the standard adult dose 5μg R21/50μg Matrix-M

  At Month 1, Month 2, Month 3, Month 11 and Month 12

• Adverse event and severe adverse event reports for safety and tolerability assessment a half of the standard adult dose 5μg R21/50μg Matrix-M with 2PE preservative vs, without 2PE preservative.

  At Month 1, Month 2, Month 3, Month 11 and Month 12

Other Outcomes (3)

• Prevalence and level of vaccine-induced antibodies.

  At Month 0, Month 3, Month 11 and Month 12

• Prevalence and level of immunity to malaria and immunological responsiveness that may be relevant to prior malaria exposure and be used to predict vaccine immunogenicity.

  At Month 0, Month 3, Month 11 and Month 12

• Prevalence and level of other factors affecting vaccine immunogenicity, such as antibodies against viral pathogens including cytomegalovirus.

  At Month 0, Month 3, Month 11 and Month 12

Study Arms (3)

The standard adult vaccine dose

ACTIVE COMPARATOR

Adults and adolescents receiving the standard adult vaccine dose

Biological: 10μg R21/50μg Matrix-M

A half of the standard adult vaccine dose with adaptor Preservative Free

ACTIVE COMPARATOR

Adults and adolescents receiving a half of the standard adult vaccine dose with adaptor Preservative Free (n=125)

Biological: 5μg R21/50μg Matrix-M with adaptor preservative free

A half of the standard adult vaccine dose with 2PE Preservative

ACTIVE COMPARATOR

Adults and adolescents receiving a half of the standard adult vaccine dose with 2PE Preservative (n=125)

Biological: 5μg R21/50μg Matrix-M with 2PE preservative

Interventions

10μg R21/50μg Matrix-M BIOLOGICAL

Adults and adolescents receiving the standard adult vaccine dose: 10μg R21/50μg Matrix-M (n=125)

The standard adult vaccine dose

5μg R21/50μg Matrix-M with 2PE preservative BIOLOGICAL

Adults and adolescents receiving a half of the standard adult vaccine dose: 5μg R21/50μg Matrix-M using two presentations: 10 dose vials with 2PE Preservative (n=125)

A half of the standard adult vaccine dose with 2PE Preservative

5μg R21/50μg Matrix-M with adaptor preservative free BIOLOGICAL

Adults and adolescents receiving a half of the standard adult vaccine dose: 5μg R21/50μg Matrix-M using two presentations: 10 dose vials with adaptor Preservative Free (n=125)

A half of the standard adult vaccine dose with adaptor Preservative Free

Eligibility Criteria

• Age: 14 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Residence in a study village for the study period, i.e. 12 months.
• Age 14 years to 60 years.
• Written informed consent/assent provided by participants (or a parent/guardian in case the participant is under 18 years old).

You may not qualify if:

• Pregnancy, plan to get pregnant within one month of vaccination, or breastfeeding.
• Acute illness requiring intervention.
• A history of an adverse reaction to study vaccine.
• Prior receipt of any other malaria vaccine.
• Enrolment in another intervention trial in the last month.
• Planned enrolment in another intervention trial in the coming 12 months.
• Regular use of Immunomodulating drugs e.g, Steroid, Methotrexate, Immunotherapy etc. in the past month and/or planned for the coming 12 months.

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (2)

Lama Upazila Health Complex

Lāma, Lama, 4641, Bangladesh

Location

Alikadam Upazila Health Complex

Bāndarban, 4650, Bangladesh

Location

MeSH Terms

Conditions

Malaria, Falciparum; Malaria

Condition Hierarchy (Ancestors)

Protozoan Infections; Parasitic Diseases; Infections; Mosquito-Borne Diseases; Vector Borne Diseases

Central Study Contacts

Lorenz von Seidlein

CONTACT

+66926486322; Lorenz@tropmedres.ac

Rupam Tripura

CONTACT

+8801572288558; Rupam@tropmedres.ac

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 2, 2025
• First Posted: September 26, 2025
• Study Start: April 1, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: March 16, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: ICF, CSR

Locations

BA (2)