Amgen earns almost all of its revenue by selling medicines, and those medicines fall into two groups. The older group still brings in a great deal of money, but its protection is wearing away. Prolia, a treatment for thinning bones, lost its exclusivity in 2025. The government has set the Medicare price of a long-standing arthritis drug since January 2026.
The newer group is meant to take over. It includes Repatha, an antibody that lowers cholesterol; a second bone medicine; an asthma drug that acts on the lining of the airways; and cancer treatments that bring the body's immune cells into contact with tumors. Rare diseases belong here too. When Amgen bought Horizon in 2023, it gained drugs for thyroid eye disease and for a severe, stubborn form of gout.
Most of the money comes from America, which brought in 71.9% of revenue. The buyers there are few. Three customers account for 77% of Amgen's revenue. Six large health plans and pharmacy benefit managers, that is, the firms that decide which drugs insurers will cover, control about 89% of American pharmacy prescriptions. Each of these buyers probably carries real weight when prices are negotiated.
Amgen has started to go around them in places. A patient with high cholesterol can now buy Repatha directly from the company. In December 2025, Amgen offered the same arrangement for two more medicines. It is also building plants in North Carolina and Ohio, which it says went up faster and cheaper than traditional sites. As the company presents it, its future depends on the newer drugs growing faster than the older ones shrink.
