Vaccines Global Summit

Vaccine Adjuvants play a critical role in modern vaccine development and are here to augment the immune response to a vaccine, thus making it stronger and more effective at giving immunity against disease-causing agents. An adjuvant is an agent added to a vaccine that boosts the body's natural response to the active ingredients of the vaccine, often antigens. In producing more vigorous or longer-lasting immunity, adjuvants allow vaccines to work better, sometimes with less antigen or fewer injections.

Adjuvants are particularly valuable in vaccines for diseases in which the body will not otherwise produce an adequate response to the antigen alone. Essentially, what they do is enhance a more robust activation of the immune system, encourage antibody production, enhance T cell responses, or prolong the memory of the immune system against a pathogen. Thus, the body will be adequately prepared to recognize and combat actual infection should it occur in the future.

One of the most frequently used adjuvants is aluminum salts, also known as alum, which have been used in vaccines for decades. This allows the slow release of the antigen, which gives the immune system enough time to recognize and react more vigorously to it. It has proven very effective with vaccines like hepatitis B and human papillomavirus (HPV). Newer, more advanced adjuvants also are in development to further optimize vaccine performance.

For example, squalene-based adjuvants, such as MF59, are included in influenza vaccines to improve elicitation of better immunogenicity in older adults whose immunity has waned somewhat. Other advanced adjuvants include AS01, which have been used in vaccines against diseases like malaria and shingles, providing more targeted immune stimulation.

Another area of importance for vaccine adjuvants is the preparation of vaccines against newly emerging infectious diseases and in populations whose immune system responsiveness may be lower, including the elderly, young children, and even those with chronic medical conditions. Adjuvants can enhance the response by the body to the vaccine, thus offering more protection to these groups.

In addition to their role in increasing the effectiveness of vaccines, adjuvants decrease the required antigen dosing, which is often higher than normal, a factor that would be very important in the event of a pandemic when vaccine supply is low or scarce or when vaccines have to be prepared quickly. That special property of adjuvants in enhancing immune responses while saving resources has made them an essential part of vaccine development.