Who Amgen buys from and sells to
Makes biologic drugs (Repatha, Prolia, Tepezza, biosimilars) mostly in its own plants, sold via US wholesalers.
Part of GLP-1 and Specialty Pharmaceuticals spending
Buys from 2
- West PharmaceuticalWSTSmartDose on-body injector for Repatha
- Horizon-era contract manufacturersTepezza and Krystexxa drug substance, many single-source
Where the chain could break
- Three wholesalers took 77% of 2025 gross revenue
- Krystexxa drug substance comes from a single contract manufacturer in Israel
- Prolia/Xgeva biosimilars erode a major franchise from 2025
Competes with
- RegeneronREGNPraluent against Repatha in PCSK9 cholesterol
- Eli LillyLLYthe obesity market MariTide is trying to enter
- Novo NordiskNVOthe same
Mapped by hand from filings and company reporting, as of October 2026. It shows the relationships that matter most, not every contract: most are never disclosed, and agreements change.