Pfizer (NYSE:PFE) released in a press statement yesterday that its anticonvulsant drug Lyrica met the primary endpoints in a phase 3 study judging the medication's effectiveness as an epilepsy therapy for patients with refractory partial onset seizures.

The study showed that Lyrica reduced seizures by at least 50% in an acceptable amount of patients. It also proved Lyrica to be as effective as a comparable treatment, the seizure therapy Keppra.

Refractory partial onset seizures refer to those incidents that medication alone cannot completely control. Lyrica is already approved for a number of other indications around the world, such as fibromyalgia and neuropathic pain. Pfizer's previous studies for the medication's effectiveness against epilepsy have been mixed, however, including a 2012 study involving a once-a-day Lyrica formulation that failed.

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