On 16 April 2025, EmblemHealth, a US nonprofit health insurer, filed a class action complaint in the US District Court for the District of Massachusetts alleging that AstraZeneca subsidiary, Alexion Pharmaceuticals, has unlawfully delayed the introduction of biosimilar competition to Soliris® (eculizumab) by misusing its patents.
According to Emblem’s complaint, Alexion wrongly obtained new patents to block biosimilar versions of Soliris® for four years after its patents on the drug should have expired. Emblem seeks compensation on behalf of US purchasers of eculizumab for “overpayments” they allegedly made (estimated to exceed USD 2 billion) during the four-year delay in biosimilar availability as well as an order ending Alexion’s “monopoly” on Soliris®.
The lawsuit follows the launch of two eculizumab biosimilars in the US: Teva/Samsung Bioepis’ Epysqli® on 7 April 2025 and Amgen’s Bkemv® in March 2025. Both Samsung Bioepis (in September 2024) and Amgen (in May 2020) reached settlements with Alexion in relation to their eculizumab biosimilars.