The US Food and Drug Administration (FDA) has granted accelerated approval for eculizumab (Soliris) to treat patients with atypical hemolytic uremic syndrome (aHUS).
This rare and chronic disease can lead to renal failure and is associated with an increased risk of death and stroke. It accounts for 5% to 10% of all cases of hemolytic uremic syndrome and disproportionately affects children.
Eculizumab is a targeted therapy that works by inhibiting proteins that play a role in aHUS. The FDA granted accelerated approval for eculizumab based on data suggesting the drug likely confers a clinical benefit for patients with aHUS.
The FDA’s Accelerated Approval Program allows for earlier approval of drugs that treat serious conditions and fill an unmet medical need based on a surrogate endpoint that is thought to predict clinical benefit. The makers of eculizumab, Alexion Pharmaceuticals, are still required to conduct research to confirm the anticipated clinical benefit.
If this research indicates that eculizumab does provide a clinical benefit, the FDA will grant traditional approval for the drug. If research suggests eculizumab does not provide a clinical benefit, the FDA has regulatory procedures in place that could lead to removing the drug from the market.
There are no other FDA-approved treatments for aHUS. The safety and efficacy of the current standard treatment, plasma therapy (plasma exchange or fresh frozen plasma infusion), have not been studied in well-controlled trials.
Researchers have examined the safety and efficacy of eculizumab in 2 single-arm trials of 37 adult and adolescent patients with aHUS and 1 retrospective study of 19 pediatric and 11 adult patients with aHUS.
Patients treated with eculizumab in these studies experienced a favorable improvement in kidney function, including elimination of the requirement for dialysis in several patients who did not respond to plasma therapy.
Patients treated with eculizumab also exhibited improvement in platelet counts and other blood parameters that correlate with aHUS disease activity.
The most common side effects included hypertension, diarrhea, headache, anemia, vomiting, nausea, upper respiratory and urinary tract infections, and leukopenia.
Eculizumab will continue to be available only through a restricted program. Prescribers must enroll in a registration program and provide a medication guide to patients who receive the drug.
Eculizumab is marketed as Soliris by Alexion Pharmaceuticals, located in Cheshire, Connecticut.