What a 6% rise in coupling-reagent prices does to a 15 mg vial

Export classifications used for certain peptide intermediates leaving Chengdu were revised in August 2025. The revision does not change what may be exported; it changes the category under which it is declared, which affects the statistics anybody outside the trade uses to estimate volume.

Under the previous classification, intermediates of this type appeared in a category that also covered unrelated fine chemicals. Under the revision they appear in a narrower one. Year-on-year volume comparisons that cross the revision date are therefore comparing different definitions, a point the Journal will restate whenever it quotes trade statistics.

Chain length drives cost non-linearly. Each coupling cycle has a yield below unity, so a 30-mer at 99% per-cycle efficiency retains substantially less crude product than a 10-mer, before any purification loss. This is why the price of a peptide is a function of its sequence rather than of its mass, and why two vials of the same nominal mass can differ in cost by an order of magnitude.

"Watch the resin orders, not the press releases," said Dr Adaeze Nwafor, consultant endocrinologist, Leeds. "A company that is about to make more of something buys more of what it is made from, and that shows up first."

The Journal’s cost-stack series publishes the model and its assumptions in full and is revised whenever a reader supplies better data. Corrections to the model are printed like any other correction.