A Study of AdCh63 ME−TRAP Alone and With MVA ME−TRAP

Malaria Clinical Trial

Official title: A Phase I Study to Assess the Safety and Immunogenicity of New Malaria Vaccine Candidate AdCh63 ME-TRAP, Alone and With MVA ME-TRAP, Using a Prime-boost Delivery Schedule

Status Completed

Clinical Trial Summary

This is an open label phase I study, to assess the safety of a novel malaria vaccine, AdCh63 ME-TRAP, simian adenovirus encoding Plasmodium falciparum antigens. This follows promising phase I clinical studies of MVA ME-TRAP and preclinical studies of AdCh63 and MVA ME-TRAP used together in prime-boost regimes. All volunteers recruited will be healthy adults. They will be primed with various doses of AdCh63 ME-TRAP administered intradermally or intramuscularly. Some of the volunteers will receive a booster vaccination with MVA ME-TRAP at various doses administered via the intradermal or intramuscular route. Safety data will be collected for each of the eight regimens. Secondary aims of this study will be to assess the immune responses generated by each of these regimes.

Clinical Trial Description

ME-TRAP insert contains a fusion protein of multiple epitopes (ME) and the Plasmodium falciparum pre-erythrocytic thrombospondin-related adhesion protein (TRAP). The 'ME' is a string of 20 epitopes fused to the thrombospondin-related adhesion protein. TRAP was selected as it is well characterized and has a protective homologue in rodents. We have safely administered ME-TRAP to over 700 volunteers in the UK and Africa.

MVA vector proved to be non-contagious and avirulent. Viral replication is blocked late during infection of cells but importantly viral and recombinant protein synthesis is unimpaired even during this abortive infection. Replication-deficient recombinant MVA has been viewed as an exceptionally safe viral vector. When tested in animal model studies recombinant MVAs have been shown to be avirulent, yet protectively immunogenic as vaccines against viral diseases and cancer. Recent studies in macaques severely immuno-suppressed by SIV infection have further supported the view that MVA should be safe in immuno-compromised humans.

Simian adenoviruses have not been used previously in a clinical trial in humans. However, they are under active development as vaccines for HIV, (by GSK), and for HCV, (Merck). ;

Study Design

Allocation: Non-Randomized, Endpoint Classification: Safety Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention

Related Conditions & MeSH terms

• Malaria

• NCT number: NCT00890019
• Study type: Interventional
• Source: University of Oxford
• Status: Completed
• Phase: Phase 1
• Start date: July 2007
• Completion date: September 2011