Peptides are central compounds in the pharmaceutical industry, providing both final medications and lead compounds for the preparation of peptidomimetic or non-peptidic pharmaceuticals. Therapeutic peptides are recognised as being extremely specific in their binding to in vivo targets, resulting in them often being highly potent and very selective, whilst having very few negative side effects. Currently, there are more than 60 peptide based medicines approved for use by the US Food & Drug Administration, around 140 peptide drugs currently in clinical trials and over 500 in preclinical trials.