FDA Approves First Interchangeable Biosimilar of Soliris

The FDA has approved Amgen’s Bkemv (eculizumab-aeeb) as the first interchangeable biosimilar to Soliris (eculizumab). Bkemv is approved for two of Soliris indications: to treat patients with paroxysmal nocturnal hemoglobinuria (PNH) and patients with atypical hemolytic uremic syndrome (aHUS).

PNH is an ultra-rare blood disorder that is characterized by the destruction of red blood cells. PNH occurs when the complement system — a part of the body’s immune system — over-responds, leading the body to attack its own red blood cells. Atypical hemolytic uremic syndrome is a rare genetic disease in which tiny blood clots form in blood vessels and block blood flow. It can lead to kidney failure and heart disease.

Soliris, a product of Alexion, an AstraZeneca company, is also indicated to treat patients with generalized myasthenia gravis, an autoimmune disease that affects muscle control, and neuromyelitis optica spectrum disorder, a rare inflammatory disease that effects the optical nerves and spinal cord.

An Amgen spokesperson said that Bkemve will launch no later later than March 2025 as part of its agreement with Alexion. A price will be available at that time, according to the spokesperson.

Bkemv is a monoclonal antibody that binds to the complement C5 protein and inhibits activation of the complement system, a part of the body's immune system. This binding prevents the breakdown of red blood cells in the bloodstream (intravascular hemolysis) in patients with PNH and aHUS.

“Many rare conditions are life-threatening, and many do not have treatments,” Sarah Yim, M.D., director of the Office of Therapeutic Biologics and Biosimilars in the FDA's Center for Drug Evaluation and Research, said in a news release. “The FDA is committed to help facilitate the development of safe and effective interchangeable biosimilar treatments that can expand access for individuals with rare diseases whose current treatment options are limited.”

Bkemv, like Soliris, has a boxed warning about the increased risk of serious and life-threatening meningococcal infections caused by Neisseria meningitidis, the bacteria that causes meningitis and other severe infections. FDA officials said that patients should have completed meningococcal vaccination before starting Bkemv or Soliris and be monitored for early signs and symptoms of meningococcal infections.

According to the FDA, Bkemv has the same safety warnings and is expected to have the same adverse reactions as Soliris. The most frequently reported adverse reactions in the PNH randomized trial for Soliris are headache, common cold, back pain and nausea. The most frequently reported adverse reactions in aHUS single arm prospective trials for Soliris are headache, diarrhea, hypertension, upper respiratory infection, abdominal pain, vomiting, nasopharyngitis, anemia, cough, swelling of lower legs or hands, nausea, urinary tract infections and fever.

Amgen said in August 2023 that the FDA had accepted the biologics license application for its eculizumab biosimilar in the second quarter of 2023. The company had presented data at the annual meeting of the American Society of Hematology in December 2023 that showed there was no meaningful difference between its biosimilar of Soliris. The study compared Amgen’s biosimilar with Soliris in a cross-over study in which 42 patients were enrolled. Efficacy was based on a comparison hemolysis The study demonstrated similarity in clinical efficacy in both parallel and crossover comparisons in patients with PNH.