Ultomiris (AstraZeneca) is expected to face US biosimilar competition from 2035. AstraZeneca 20-F: US patent protection expected to 2035. Rare immune and blood diseases.
Ultomiris's US exclusivity date is based on company guidance. The date comes from the company's own filings or guidance. Secondary patents, new formulations or litigation can still move it. It is a biologic, so copies are biosimilars. Biosimilars are harder to make and usually erode sales more gradually than generics.
Among past biologics facing biosimilars: Humira's US sales fell to 65% of their 2022 level in its first full year of biosimilars (2023) and 16% two years later; Stelara's US sales fell to 57% of their 2024 level in its first full year of biosimilars (2025). See how past cliffs played out →
No US filing found We found no Ultomiris biosimilar program as of September 2026. Its predecessor Soliris already faces US biosimilars.
Checked September 2026. Sources: AstraZeneca 20-F 2025
Ultomiris is 8% of AstraZeneca's 2025 revenue ($4.7B of $58.7B). With Farxiga, Lynparza, Imfinzi, Tagrisso and Calquence, the drugs tracked here add up to 57% of AstraZeneca's revenue losing US exclusivity by 2035.
Bars show each company's tracked drugs as a share of its total 2025 revenue. Ultomiris is highlighted.