Module 9 2024

03/09/2024

What is an Adjuvant?

• Adjuvants may be added to enhance and modulate the immune response

• e.g., higher antibody level, longer-lasting protection, improve response in older adults

For example, they can induce:

•

⚫ a strong immune response e.g. malaria 1 ⚫ long-term protection e.g. HPV virus causing cervical cancer 2 ⚫ a broader immune response e.g. pre-pandemic flu vaccine 1

• Aluminium-based compounds (principally aluminium phosphate or hydroxide) remain the predominant human adjuvants

• But new adjuvants being licensed as part of new vaccines

• e.g. QS-21*; Monophospholipid (MPL)

The Organisation for Professionals in Regulatory Affairs

Garçon N. et al , GlaxoSmithKline Adjuvant Systems in vaccines in Expert Rev.Vaccines 6(5 ), 2007, pp.723-739 ; 2. Garçon N. and Goldman M., Boosting Vaccine Power, in Scientific American , October 2009 , pp. 72-79. * Saponin extracted from the bark of the Quillaja saponaria tree

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Adjuvants can enhance immune responses and improve multiple facets of the response to vaccination

Reference 1 (n.b. Not applicable to live vaccines)

Adjuvant

Vaccine with Adjuvant System

Substance included in a vaccine to enhance and modulate the quality and/or strength of the immune response induced by the antigen(s) Adjuvants are not licenced on their own but only as part of an adjuvanted vaccine

Vaccine without adjuvant

Amplitude

Time

Quality & Breadth of T cell and antibody response

Enhanced immune responses (multiple effector functions)

Efficacy across age groups and IC

Acceptable safety profile

Antigen sparing

Durability of the response

Reference 2

1. Adapted from ref: Pulendran B. et al – Cell 2006; 124:849-863 2. Pulendran B, S Arunachalam P, O'Hagan DT. Emerging concepts in the science of vaccine adjuvants. Nat Rev Drug Discov. 2021 Jun;20(6):454-475. doi: 10.1038/s41573-021-00163-y. Epub 2021 Apr 6. PMID: 33824489; PMCID: PMC80237

The Organisation for Professionals in Regulatory Affairs

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