TY - JOUR
T1 - The candidate blood-stage malaria vaccine P27A induces a robust humoral response in a fast track to the field Phase 1 trial in exposed and nonexposed volunteers
AU - Steiner-Monard, Viviane
AU - Kamaka, Kassim
AU - Karoui, Olfa
AU - Roethlisberger, Samuel
AU - Audran, Régine
AU - Daubenberger, Claudia
AU - Fayet-Mello, Aurélie
AU - Erdmann-Voisin, Aude
AU - Felger, Ingrid
AU - Geiger, Kristina
AU - Govender, Lerisa
AU - Houard, Sophie
AU - Huber, Eric
AU - Mayor, Carole
AU - Mkindi, Catherine
AU - Portevin, Damien
AU - Rusch, Sebastian
AU - Schmidlin, Sandro
AU - Tiendrebeogo, Regis W
AU - Theisen, Michael
AU - Thierry, Anne-Christine
AU - Vallotton, Laure
AU - Corradin, Giampietro
AU - Leroy, Odile
AU - Abdulla, Salim
AU - Shekalaghe, Seif
AU - Genton, Blaise
AU - Spertini, François
AU - Jongo, Said A
PY - 2019/1/18
Y1 - 2019/1/18
N2 - Background. P27A is an unstructured 104mer synthetic peptide from Plasmodium falciparum trophozoite exported protein 1 (TEX1), the target of human antibodies inhibiting parasite growth. The present project aimed at evaluating the safety and immunogenicity of P27A peptide vaccine in malaria-nonexposed European and malaria-exposed African adults. Methods. This study was designed as a staggered, fast-Track, randomized, antigen and adjuvant dose-finding, multicenter phase 1a/1b trial, conducted in Switzerland and Tanzania. P27A antigen (10 or 50 ?g), adjuvanted with Alhydrogel or glucopyranosil lipid adjuvant stable emulsion (GLA-SE; 2.5 or 5 ?g), or control rabies vaccine (Verorab) were administered intramuscularly to 16 malaria-nonexposed and 40 malaria-exposed subjects on days 0, 28, and 56. Local and systemic adverse events (AEs) as well as humoral and cellular immune responses were assessed after each injection and during the 34-week follow-up. Results. Most AEs were mild to moderate and resolved completely within 48 hours. Systemic AEs were more frequent in the formulation with alum as compared to GLA-SE, whereas local AEs were more frequent after GLA-SE. No serious AEs occurred. Supported by a mixed Th1/Th2 cell-mediated immunity, P27A induced a marked specific antibody response able to recognize TEX1 in infected erythrocytes and to inhibit parasite growth through an antibody-dependent cellular inhibition mechanism. Incidence of AEs and antibody responses were significantly lower in malaria-exposed Tanzanian subjects than in nonexposed European subjects. Conclusions. The candidate vaccine P27A was safe and induced a particularly robust immunogenic response in combination with GLA-SE. This formulation should be considered for future efficacy trials.
AB - Background. P27A is an unstructured 104mer synthetic peptide from Plasmodium falciparum trophozoite exported protein 1 (TEX1), the target of human antibodies inhibiting parasite growth. The present project aimed at evaluating the safety and immunogenicity of P27A peptide vaccine in malaria-nonexposed European and malaria-exposed African adults. Methods. This study was designed as a staggered, fast-Track, randomized, antigen and adjuvant dose-finding, multicenter phase 1a/1b trial, conducted in Switzerland and Tanzania. P27A antigen (10 or 50 ?g), adjuvanted with Alhydrogel or glucopyranosil lipid adjuvant stable emulsion (GLA-SE; 2.5 or 5 ?g), or control rabies vaccine (Verorab) were administered intramuscularly to 16 malaria-nonexposed and 40 malaria-exposed subjects on days 0, 28, and 56. Local and systemic adverse events (AEs) as well as humoral and cellular immune responses were assessed after each injection and during the 34-week follow-up. Results. Most AEs were mild to moderate and resolved completely within 48 hours. Systemic AEs were more frequent in the formulation with alum as compared to GLA-SE, whereas local AEs were more frequent after GLA-SE. No serious AEs occurred. Supported by a mixed Th1/Th2 cell-mediated immunity, P27A induced a marked specific antibody response able to recognize TEX1 in infected erythrocytes and to inhibit parasite growth through an antibody-dependent cellular inhibition mechanism. Incidence of AEs and antibody responses were significantly lower in malaria-exposed Tanzanian subjects than in nonexposed European subjects. Conclusions. The candidate vaccine P27A was safe and induced a particularly robust immunogenic response in combination with GLA-SE. This formulation should be considered for future efficacy trials.
U2 - 10.1093/cid/ciy514
DO - 10.1093/cid/ciy514
M3 - Journal article
C2 - 29945169
SN - 1058-4838
VL - 68
SP - 466
EP - 474
JO - Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
JF - Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
IS - 3
ER -