The Cephalon drug Treanda (bendamustine hydrochloride) has been approved by the U.S. Food and Drug Administration to treat chronic lymphocytic leukemia, a rare cancer that affects the blood and bone marrow. Treanda, expected to hit the U.S. market in April, works by damaging the DNA in cancer cells, causing these cells to die. Cephalon said the treatment was granted orphan drug status by the FDA, which offers companies exclusive marketing rights in return for drugs developed for rare diseases.
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