Complement-mediated ‘atypical’ hemolytic uremic syndrome (aHUS) is a chronic and life-threatening ultra-rare genetic disease with an estimated prevalence of seven per one million individuals in which uncontrolled complement activation causes blood clots in small blood vessels throughout the body, or thrombotic microangiopathy (TMA), leading to kidney failure, stroke, heart attack and death.
The prognosis for patients with aHUS is generally poor. aHUS commonly recurs in patients who undergo renal transplantation for the kidney injury and kidney failure suffered due to uncontrolled complement activity. Approximately 50% of patients with aHUS have been identified to have genetic mutations in at least one of the complement control proteins or neutralizing autoantibodies to complement regulatory factors, which can lead to uncontrolled complement activation. Eculizumab received accelerated FDA approval in 2011 based on data from both prospective and retrospective trials in a cumulative total of 67 adult and pediatric patients.
Eculizumab remains the first and only therapy approved for the treatment of pediatric and adult patients with aHUS. Alexion, the maker of eculizumab, has noted that the opportunity for eculizumab in aHUS is at least as large as PNH, with more patients in the United States receiving eculizumab for aHUS than PNH at a similar timeframe from launch since its approval in aHUS. Given that eculizumab and Coversin have the same mechanism of action, it is anticipated that Coversin will be effective in treating aHUS patients.