The U.S. Food and Drug Administration today approved Soliris (eculizumab) to treat patients with atypical Hemolytic Uremic Syndrome (aHUS), a rare and chronic blood disease that can lead to kidney (renal) failure and is also associated with increased risk of death and stroke.
Atypical HUS accounts for 5 to 10 percent of all cases of hemolytic uremic syndrome. The disease disproportionately affects children.
Soliris is a targeted therapy that works by inhibiting proteins that play a role in aHUS. The FDA first approved Soliris in March 2007 to treat paroxysmal nocturnal hemoglobinuria (PNH), a rare type of blood disorder that can lead to disability and premature death. Soliris is classified as an orphan drug. Orphan drugs are those that demonstrate promise for the diagnosis and/or treatment of rare diseases or conditions.
There are no other FDA-approved treatments for aHUS, and the safety and effectiveness of current standard treatment, plasma therapy (plasma exchange or fresh frozen plasma infusion), have not been studied in well controlled trials.
"This is the first approval of a drug for treating this life-threatening disease, and the first approval for use of Soliris in children," said Richard Pazdur, M.D., director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research. "This approval underscores how an increased understanding of the biology of a disease and of how a drug interacts with that process can expedite drug development."
Soliris' safety and effectiveness were established in two single-arm trials in 37 adults and adolescent patients with aHUS and one retrospective study in 19 pediatric patients and 11 adult patients with aHUS. Patients treated with Soliris in these studies experienced a favorable improvement in kidney function, including elimination of the requirement for dialysis in several patients with aHUS that did not respond to plasma therapy. Patients treated with Soliris also exhibited improvement in platelet counts and other blood parameters that correlate with aHUS disease activity.
The most common side effects seen in patients treated with Soliris for aHUS included high blood pressure (hypertension), diarrhea, headache, anemia, vomiting, nausea, upper respiratory and urinary tract infections, and a decrease in white blood cells (leukopenia).
This new indication for Soliris is being approved with an extension of the existing Risk Evaluation and Mitigation Strategy (REMS), to inform health care professionals and patients about the known risk of life-threatening meningococcal infections.
Soliris will continue to be available only through a restricted program, and prescribers must enroll in a registration program and provide a medication guide to patients who receive the drug.
Soliris was reviewed under the FDA's priority review program, which provides for an expedited six-month review of drugs that may offer major advances in treatment or that provide a treatment when no adequate therapy exists.
The therapy also is being approved under the FDA's accelerated approval program, designed to provide patients with earlier access to promising new drugs followed by further studies to confirm the drug's clinical benefit.
The accelerated approval program allows the agency to approve a drug to treat a serious disease based on clinical data showing that the drug has an effect on an endpoint that is reasonably likely to predict a clinical benefit to patients, or on an effect on a clinical endpoint other than survival or irreversible morbidity.
Soliris is marketed by Alexion Pharmaceuticals in Cheshire, Conn.