This
review discusses peptide epitopes used as antigens in the
development of vaccines in clinical trials as well as future vaccine
candidates. It covers peptides used in potential immunotherapies for
infectious diseases including SARS-CoV-2, influenza, hepatitis B and
C, HIV, malaria, and others. In addition, peptides for cancer vaccines
that target examples of overexpressed proteins are summarized, including
human epidermal growth factor receptor 2 (HER-2), mucin 1 (MUC1),
folate receptor, and others. The uses of peptides to target cancers
caused by infective agents, for example, cervical cancer caused by
human papilloma virus (HPV), are also discussed. This review also
provides an overview of model peptide epitopes used to stimulate non-specific
immune responses, and of self-adjuvanting peptides, as well as the
influence of other adjuvants on peptide formulations. As highlighted
in this review, several peptide immunotherapies are in advanced clinical
trials as vaccines, and there is great potential for future therapies
due the specificity of the response that can be achieved using peptide
epitopes.