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Efficacy of Malaria Vaccines in Kenyan Adults

NCT01666925 · Status: COMPLETED · Phase: PHASE2 · Type: INTERVENTIONAL · Enrollment: 120

Last updated 2013-12-12

No results posted yet for this study

Summary

Malaria transmission is falling in some parts of Africa as bed nets and anti-malarials become more widely available. However, transmission still persists and it appears that additional control measures are required. The leading malaria vaccine candidate in development is RTS,S which has efficacy against clinical malaria measured at 30-50% in the field. This partial protection might be enhanced by combination with other components. The other vaccination approach that has produced repeatable efficacy in humans is the use of viral vectors to induce T cell responses. Previous attempts with this vaccine approach have been effective in challenge studies in Oxford, but ineffective in the field, probably because of reduced immunogenicity.

Recently, studies in Oxford, Kenya and the Gambia have shown higher levels of immunogenicity by using a chimpanzee adenovirus (ChAd63) followed by an attenuated vaccinia virus (modified vaccinia Ankara) to deliver the pre-erythrocytic antigen, multiple epitope string with thrombospondin- related adhesion protein (ME-TRAP).

The increase in immunogenicity has lead to sterile protection in 3 out of 14 volunteers and partial protection in 5 out of 14 volunteers in challenge studies.

The investigators propose a Phase 2b study of 120 healthy adult men in Kenya. The investigators will assess the efficacy and further evaluate the immunogenicity and safety profile of the vaccine regimen. The investigators also intend to assess the correlates of efficacy and natural immunity.

Conditions

Interventions

BIOLOGICAL

ChAd63 ME-TRAP / MVA ME-TRAP prime-boost immunisation

ChAd63 ME-TRAP: 5 x 10\^10vp MVA ME-TRAP: 2 x 10\^8 pfu

BIOLOGICAL

Rabies vaccine

2 x 2.5IU Verorab

Sponsors & Collaborators

  • European and Developing Countries Clinical Trials Partnership (EDCTP)

    collaborator OTHER_GOV

  • University of Oxford

    lead OTHER

Study Design

Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
SINGLE
Model
PARALLEL

Eligibility

Min Age
18 Years
Max Age
50 Years
Sex
MALE
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2012-03-31
Primary Completion
2012-08-31
Completion
2012-08-31

Countries

  • Kenya

Study Locations

More Related Trials

Entities

Diseases

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT01666925 on ClinicalTrials.gov