Peptides for therapeutic applications – challenges and chances

Peptides have beneficial properties for therapeutic applications due to their excellent target specificity, high affinity and activity, low toxicity and predictable metabolism. Thus, they became an important tool for research and medical purpose. However, peptides are fragile molecules, therefore, in order to be used as therapeutic agents they need to be stabilised by non-peptidic modifications. Required improvements of these peptide properties include longer half-life, higher bioavailability, increased potency and efficiency. Strategies to achieve these goals have been identified in the last years, with synthetic strategies to obtain sufficient amounts becoming increasingly important. In this review, peptides are discussed with respect to their therapeutic applications. Examples from glucagon-like peptide 1 receptor agonists are shown. Peptides are compared to small molecules and antibodies with respect to advantages and disadvantages in therapeutic applications.