Leveraging Clinical Data from One Rare Disease to Support Drug Approval for Another
Atypical hemolytic uremic syndrome (aHUS) is an ultra-rare genetic disease that causes abnormal blood clot formation in small blood vessels throughout the body leading to kidney failure, other organ damage, and premature death. At the start of this project, there were no FDA-approved aHUS treatments. Furthermore, as only a few thousand aHUS patients are diagnosed each year, recruiting enough participants to conduct clinical trials was difficult.
However, the FDA had approved a humanized monoclonal antibody (mAb), eculizumab, to treat a related, rare, life-threatening disease – paroxysmal nocturnal hemoglobinuria (PNH), which is characterized by destruction of red blood cells and excessive blood clotting. Both aHUS and PNH symptoms result from chronic, uncontrolled complement system activation. Knowing eculizumab’s mechanism of action for PNH suggested that it could confer clinical benefit in aHUS.