Phase Ia Malaria Vaccine Trial of Two Virosome-Formulated Peptides
Influenza virosomes represent an innovative human-compatible antigen delivery system that has already proven its suitability for subunit vaccine design. The aim of the study was to proof the concept that virosomes can also be used to elicit high titers of antibodies against synthetic peptides derived from the circumsporozoite protein and from the apical-membrane-antigen 1 and that the formulations are safe in humans.
Biological: Virosome-formulated synthetic peptides (malaria vaccine)
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind
Primary Purpose: Prevention
|Official Title:||A Randomized Placebo-Controlled Phase Ia Malaria Vaccine Trial of Two Virosome-Formulated Synthetic Peptides in Healthy Adult Volunteers|
- Incidence of adverse events
- Antibody concentration by Elisa
- Antibody concentration by IFAT and Western blot
- Cellular immunity
|Study Start Date:||November 2003|
|Estimated Study Completion Date:||October 2005|
Influenza virosomes represent an innovative human-compatible antigen delivery system that has already proven its suitability for subunit vaccine design. The aim of the study was to proof the concept that virosomes can also be used to elicit high titers of antibodies against synthetic peptides. The specific objective was to demonstrate the safety and immunogenicity of two virosome-formulated P. falciparum protein derived synthetic peptide antigens given in two different doses alone or in combination.
Methodology The design was a single blind, randomized, placebo controlled, dose-escalating study involving 46 healthy Caucasian volunteers aged 18-45 years. Five groups of 8 subjects received virosomal formulations containing 10 ug or 50 ug of AMA 49-CPE, an apical membrane antigen-1 (AMA-1) derived synthetic phospatidylethanolamine (PE)-peptide conjugate or 10 ug or 50 ug of UK39, a circumsporozoite protein (CSP) derived synthetic PE-peptide conjugate or 50 ug of both antigens each. A control group of 6 subjects received unmodified virosomes. Virosomal formulations of the antigens (designated PEV301 and PEV302 for the AMA-1 and the CSP virosomal vaccine, respectively) or unmodified virosomes were injected i. m. on days 0, 60 and 180.