A pivotal trial of Gilead Sciences Inc's experimental drug idelalisib has been stopped early after independent monitors determined that the drug was shown to be effective.
The Phase 3 trial compared treatment with idelalisib and another drug, Rituxan, to treatment with Rituxan alone in patients with chronic lymphocytic leukemia who were not eligible for treatment with chemotherapy.
Idelalisib is part of a new class of medications designed to selectively block a type of protein known to promote tumor growth in certain types of blood cancer.
Gilead said an interim analysis by the Data Monitoring Committee overseeing the trial found that the drug had a significant impact on the length of time patients survived without their disease getting worse.
Gilead said it is discussing the trial results, and a potential regulatory filing, with the U.S. Food and Drug Administration.
The company filed last month for FDA approval of the drug as a treatment for non-Hodgkin's lymphoma.
Idelalisib patients in the recently stopped trial will continue receiving the drug, while others will be offered the option of switching to the experimental pill, Gilead said.
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