Amgen

Amgen is based in Thousand Oaks and built its business on biologics. Enbrel is the etanercept autoimmune drug, Prolia and Xgeva are denosumab for bone, and Repatha is the PCSK9 cholesterol antibody.

Otezla, the oral psoriasis drug Amgen bought when Bristol Myers acquired Celgene, is promoted to dermatologists beside injections. Tepezza, for thyroid eye disease, came with the Horizon deal that closed in 2023 and is infused in specialty clinics that also use Krystexxa.

Denosumab biosimilars and etanercept competition outside the United States press the older brands, while Repatha still fights for a preferred cardiology tier against other PCSK9 products. A clinic that buy-and-bills Tepezza depends on payer policy for a rare infusion, not on a retail shelf.

Enbrel's remaining patent life in the United States delays automatic substitution that already exists in Europe.

Prolia prescriptions are sensitive to biosimilar denosumab pricing at the pharmacy benefit.

Tepezza volume sits in a small number of infusion centers and specialty pharmacies.

A rheumatology patient on Enbrel has years of dose history that a payer switch would interrupt.

Eye and rheumatology clinics financing Tepezza buy-and-bill carry the receivable until the payer approves.