Therapeutic Peptides: Why Demand Is Growing and What Makes Them Complex to Make
Peptides, short chains of amino acids, sit between small-molecule drugs and large biologics. Over the last decade they have moved from a niche area to one of the most active segments in pharmaceutical development, helped by the success of therapies such as GLP-1 receptor agonists for diabetes and weight management.
Why peptides are attractive
- High specificity: peptides bind precisely to their targets, which can mean fewer off-target effects.
- Good safety profile: they break down into natural amino acids in the body.
- Broad applications: metabolic disorders, oncology, hormonal therapies, antimicrobials and more.
How peptides are made
The most common method is Solid-Phase Peptide Synthesis (SPPS). The peptide chain is built one amino acid at a time while attached to a resin. After each coupling step, protecting groups are removed and the next amino acid is added. Once the full sequence is assembled, the peptide is cleaved from the resin and purified, usually by preparative HPLC, before lyophilisation.
Some processes also use liquid-phase or hybrid approaches, especially for longer sequences or large commercial volumes.
Key manufacturing challenges
- Impurity control: each coupling step can create deletion or truncated sequences that must be removed.
- Purification yield: separating closely related impurities needs strong chromatography expertise.
- Scale-up: processes that work at gram scale need careful optimisation to work at kilogram scale.
- Analytical characterisation: identity, purity, peptide content and counter-ion levels all need validated methods.
- Solvent and reagent management: SPPS uses large volumes of solvents, so efficiency and safety matter.
Peptides and complex generics
As patents expire on established peptide drugs, generic manufacturers need partners who can demonstrate equivalence through detailed characterisation and impurity comparison. This makes peptide generics a “complex generic” category that demands more than routine manufacturing.
Marigold Pharma supports peptide and small-molecule programmes from development to supply. Learn more about our peptide capabilities.