Vaccine Potentiation by Combination Adjuvants.
Adjuvants are crucial components of vaccines. They significantly improve vaccine efficacy by modulating, enhancing, or extending the immune response and at the same time reducing the amount of antigen needed. In contrast to previously licensed adjuvants, current successful adjuvant formulations often consist of several molecules, that when combined, act synergistically by activating a variety of immune mechanisms. These "combination adjuvants" are already registered with several vaccines, both in humans and animals, and novel combination adjuvants are in the pipeline. With improved knowledge of the type of immune responses needed to successfully induce disease protection by vaccination, combination adjuvants are particularly suited to not only enhance, but also direct the immune responses desired to be either Th1-, Th2- or Th17-biased. Indeed, in view of the variety of disease and population targets for vaccine development, a panel of adjuvants will be needed to address different disease targets and populations. Here, we will review well-known and new combination adjuvants already licensed or currently in development-including ISCOMs, liposomes, Adjuvant Systems Montanides, and triple adjuvant combinations-and summarize their performance in preclinical and clinical trials. Several of these combination adjuvants are promising having promoted improved and balanced immune responses.
VIDO-Intervac, University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada. benoit.levast@mail.mcgill.ca.
Benoît
B
Levast
VIDO-Intervac, University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada. sua784@mail.usask.ca.
Sunita
S
Awate
University Hall, University of Alberta, Edmonton, AB T6G 2J9, Canada. lbabiuk@ualberta.ca.
Lorne
L
Babiuk
VIDO-Intervac, University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada. george.mutwiri@usask.ca.|School of Public Health, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada. george.mutwiri@usask.ca.
George
G
Mutwiri
VIDO-Intervac, University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada. volker.gerdts@usask.ca.|Veterinary Microbiology, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N 5B4, Canada. volker.gerdts@usask.ca.
Volker
V
Gerdts
VIDO-Intervac, University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada. sylvia.vandenhurk@usask.ca.|Microbiology and Immunology, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada. sylvia.vandenhurk@usask.ca.
Sylvia
S
van Drunen Littel-van den Hurk
adjuvants; combinations; human clinical trials; review