First Commercialization Milestone in the EU

The European Commission approved Epysqli (eculizumab) from Samsung Bioepis on May 26, 2023, for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). This signifies that SB12, the development code, has completed the clinical development phase and transitioned into an approved, marketable product. The Committee for Medicinal Products for Human Use (CHMP) under the EMA adopted a positive opinion on March 30 of the same year. The final decision was made through the EU centralized procedure, rather than an advisory committee (AdComm) process as seen in the United States. The marketing authorization holder is Samsung Bioepis NL B.V., and Samsung Bioepis is directly establishing a sales and distribution system in Europe.

Demonstrated Equivalence to C5 Inhibitor

Epysqli is a biosimilar of eculizumab, a monoclonal antibody that targets the complement protein C5, with Soliris (eculizumab) from AstraZeneca's Alexion as the reference product. In a multinational, randomized, double-blind, Phase 3 trial involving 50 patients, the average lactate dehydrogenase (LDH) level at 26 weeks was approximately 284 U/L for Epysqli and approximately 250 U/L for Soliris. The difference in LDH and the area under the time-adjusted effect curve (AUEC) fell within the pre-defined equivalence range, supporting clinical equivalence. Therefore, this approval is primarily based on the totality of analytical, pharmacokinetic, and clinical data, rather than demonstrating independent superiority in efficacy compared to the originator product.

Triggering Price Competition in the Rare Disease Market

Soliris' global sales in 2023 were $3.145 billion, reflecting the economic base that Epysqli targets. In PNH, C5 inhibition, which reduces the need for blood transfusions and the risk of thrombosis, has revolutionized the treatment paradigm, but long-term intravenous administration and high drug costs have been barriers to access. Epysqli will compete directly with Amgen's Bekemv (eculizumab), another biosimilar, and will compete with Ultomiris (ravulizumab), an 8-week long-acting C5 inhibitor, in terms of price and ease of administration. The extent of price reductions in national tenders and reimbursement negotiations will determine the speed of adoption, making actual prescription conversion rates more important than the approval itself in determining commercial success.

Regulatory Expansion and Safety Management

The EMA's current marketing authorization includes not only adult and pediatric PNH but also atypical hemolytic uremic syndrome (aHUS), expanding the indication base. The U.S. FDA also approved Epysqli (eculizumab-aagh) as a biosimilar to Soliris for PNH and aHUS on July 19, 2024, and subsequently expanded the label to include acetylcholine receptor antibody-positive generalized myasthenia gravis. C5 inhibition increases the risk of life-threatening meningococcal infections, so vaccination confirmation and infection monitoring before administration are essential. This safety management burden is common to both biosimilars and originator products, so the focus of competition is shifting from clinical differentiation to price, supply stability, and hospital conversion support.