R21/MM Dosing, Presentations, and Preservatives (VAC100)

University of Oxford

Status and phase: Begins enrollment this month; Phase 4

Conditions: Vaccine Reaction; Malaria; Plasmodium Falciparum Malaria

Treatments: Biological: 5μg R21/50μg Matrix-M with adaptor preservative free; Biological: 5μg R21/50μg Matrix-M with 2PE preservative; Biological: 10μg R21/50μg Matrix-M

Study type: Interventional

Funder types: Other

Identifiers

NCT07194668

MAL25005

Details and patient eligibility

About

This is a single blind randomised controlled 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 child 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:

1. The standard dose (10μg R21/50μg Matrix-M) of the malaria vaccine is administered in three doses over a two-month period (at Month 0, 1, and 2), followed by a booster dose at Month 11 (n=125).

   or

2. A half dose (5μg R21/50μg Matrix-M) of the malaria vaccine is administered in three doses over a two-month period (at Month 0, 1, and 2), followed by a booster dose at Month 11.

If participant receive the half dose, it will come from one of two types of vaccine:

2a. 10 dose vials with adaptor Preservative Free (n=125) 2b. 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

Enrollment: 375 estimated patients

Sex: All

Ages: 14 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 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).

Exclusion criteria

• 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.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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375 participants in 3 patient groups

The standard adult vaccine dose

Active Comparator group

Description:

Adults and adolescents receiving the standard adult vaccine dose

Treatment:

Biological: 10μg R21/50μg Matrix-M

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

Active Comparator group

Description:

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

Treatment:

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

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

Active Comparator group

Description:

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

Treatment:

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