A century old, and accelerating

Insulin in the 1920s through the long middle stretch when the class stalled, to the engineering that revived it.

Read at your level

The standard read.

Insulin entered clinical use in the 1920s, and peptides have been part of medicine ever since. Reviews of peptide drug development describe a long middle stretch in which the class was held back by exactly the problems above, followed by a marked acceleration as synthesis, stabilisation chemistry, and delivery methods improved.

The field today is genuinely active and genuinely uneven. Some peptide classes are supported by large controlled trials; many more are supported only by laboratory and animal work. Treating those two situations as though they were the same is the most common error in how this subject is discussed — which is why trial counts sit beside every compound class rather than a single undifferentiated claim.

Watch alongside

Films beside this reading

The clinicians and researchers this topic draws on, in their own words. Each film was verified before it was listed. The full collection lives in the video library.

Northwestern Univ. Feinberg School of MedicineThe Emerging Science and Clinical Application of Peptide TherapyA medical school lecture on peptide therapeutics — what the class is, how these molecules are used clinically, and where the research currently sits.Why it belongs hereSets out what the class is and how clinical interest in it arose, before any single compound is discussed — the orientation the rest of the course assumes.

NBC NewsWhat are peptides and why is the FDA considering easing limits?A short news explainer on the compound class and the regulatory reclassification question, for anyone starting from zero.Why it belongs hereA short, neutral news explainer, useful for seeing how the subject is being described to a general audience while the regulatory position moves.

Matt Kaeberlein, PhDTargeting biological ageing: a new paradigm for 21st century medicineThe case for treating ageing biology as a therapeutic target, presented at a university medical faculty.Why it belongs herePlaces the whole field in its historical arc: why ageing biology became a therapeutic target at all, which is where this lesson ends.

End of this path

That is the full reading

6 topics, each readable at three levels and cited to the record. Revisit any of them, or follow the evidence into the library.

The research library →How to read the evidence →The citation index →

This section is educational reference material about peptide biochemistry, drawn from the review literature and cited throughout. It is not medical advice, it is not tailored to anyone’s circumstances, and it makes no claim about any product sold on this site. It describes what a class of molecules is and how it behaves, never what any compound does for a person.