Lilly and Novo Nordisk: The Incumbents in ObesityThin moat

In obesity Amgen is the challenger, and the market it wants to enter is already held by two companies whose contest is described on Eli Lilly's pages in this app, Novo Nordisk and the GLP-1 War among them. Amgen's candidate, MariTide, is not yet approved; its data and the market's reaction to them are the subject of the Future Bets page. This page is about how Amgen proposes to compete.

The plan is dosing. Amgen describes MariTide as starting with monthly dosing, and staying on MariTide with as few as 4 or 6 doses per year¹, against the weekly injections the incumbents' drugs have required. A patient who needs a few injections a year rather than one a week is an argument for switching.

Amgen is testing that argument directly. Among its Phase 3 studies is MARITIME-SWITCH, which enrolls patients moving from tirzepatide or semaglutide, the incumbents' molecules, onto MariTide given every eight weeks or quarterly². A company that designs a trial around taking patients from rivals knows it arrives late.

It has also narrowed its bets. The second-quarter 2026 release says future development of AMG 513, a second obesity candidate, will be discontinued³.

The incumbents have scale, supply and years of prescribing behind them. What Amgen has is a different dosing schedule and a patent on MariTide's antibody-peptide conjugates to 2038⁴. The first readout that will say whether dosing is enough is MARITIME-SWITCH; if patients switched from the incumbents keep their weight off on quarterly doses, Amgen has a place in the market, and if they do not, it has a late entry with nothing distinctive.