Cerus Corporation announced that it has been granted orphan drug status for plasma prepared with the INTERCEPT Blood System for treatment of thrombotic thrombocytopenic purpura (TTP). TTP is a rare, life-threatening blood disorder that typically requires transfusion with large volumes of plasma. Orphan drugs are required to establish safety and efficacy prior to approval by the United States Food and Drug Administration (FDA). The designation facilitates the application process in order to encourage development of new therapies to treat rare conditions and diseases.

“This designation is a significant step toward making INTERCEPT plasma available to a very vulnerable US patient population,” commented Claes Glassell, Cerus' president and chief executive officer. “Patients with TTP are at heightened risk for transfusion transmitted disease given the considerable volumes of plasma used in therapeutic exchange procedures. We look forward to working with the FDA to determine their requirements for a TTP indication approval.”

The incidence of TTP is estimated to be as high of 3500 patients per year in the United States. There are no drugs approved for treatment of TTP, and episodes are associated with significant risk of mortality from widespread blood clotting which restricts blood flow to critical organs such as the brain, kidneys and heart. Over the course of treatment, a patient may receive in excess of 40 liters of plasma, representing exposure to plasma units from over 200 blood donors.

In 2004, Cerus completed a phase 3 study of 35 TTP patients in which almost 3000 units of INTERCEPT plasma were transfused. The results were published in the journal Transfusion in 2006 (Mintz et al. Transfusion 2006;46:1693-1704). The primary endpoint of the trial, comparing the proportion of patients in the test and control groups achieving remission within 30 days after the first therapeutic plasma exchange, was met (82% treated vs. 89% control groups). All secondary efficacy endpoints, comparing time to first remission, relapse rates and plasma exchange volume, were also met. INTERCEPT plasma is currently approved in Europe for use in all indications of plasma for transfusion, including treatment of TTP.

Cerus Corporation is a biomedical products company focused on commercializing the INTERCEPT Blood System to enhance blood safety. The INTERCEPT system is designed to reduce the risk of transfusion-transmitted diseases by inactivating a broad range of pathogens such as viruses, bacteria and parasites that may be present in donated blood.