Therapeutic peptides revisited: After a roller coaster ride of successes and failures, new discovery technologies and advances in manufacturing promise a brighter future for peptides in human therapy

Some 40 years after Nobel laureate Bruce Merrifield first described resin-based peptide synthesis, remarkably few therapeutic peptide products have made it to the clinic. Time and time again, difficulties with delivery, stability, and synthesis have hampered commercialization of these medicines. Above all, cost-effective and reliable peptide manufacture has proved an elusive goal, considerably diminishing the attractiveness of peptide therapeutics as alternatives to small-molecule drugs. Now, new means not only of synthesizing longer peptides in greater quantities, but also of screening and optimizing peptide leads, have resulted in an explosion in the number of candidate peptides and a renewed interest in the commercial development of these molecules.