In 1992, Bell left a teaching job at Yale to start biotech company Alexion. Fifteen years and $800 million later, he emerged with Soliris, the first FDA-approved drug of its kind that blocks `terminal complement,' a naturally occurring part of the immune system that plays a role in the life-threatening blood disease called PNH. Patients suffering from PNH and treated with Soliris experience its beneficial effects within days. Now Bell and Alexion are focusing on the potential benefits of Soliris on patients with other rare diseases for which there are no treatments, as well as kidney transplant patients who face a particularly high risk of organ rejection. --J.P.M.
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Last updated July 09 2010: 1:19 PM ET