The story

Tirzepatide came out of the Eli Lilly labs in Indianapolis, where Tamer Coskun and his team set out to put two incretin signals into one molecule. They published the discovery as LY3298176 in 2018, showing that a single peptide could act on both the GIP and GLP-1 receptors and outperform GLP-1 alone on weight and glucose. In 2020 Francis Willard showed why: it is imbalanced and biased, strong on GIP and gentle and selective on GLP-1. Japanese and Chinese groups then mapped its effect in East Asian bodies, where visceral fat drives disease at lower weights, and Russian endocrinologists now describe it as unimolecular polypharmacology: one molecule doing the work of several medicines. Polish reviews in 2026 traced its action down to the neuroendocrine circuits of appetite.