XenoPort, Inc announced that the US Food and Drug Administration (FDA) has accepted for review the new drug application (NDA) filed by GlaxoSmithKline (GSK) for Solzira (gabapentin enacarbil) Extended Release tablets in the United States as a potential treatment for moderate-to-severe primary Restless Legs Syndrome (RLS). In accordance with XenoPort's collaboration agreements with GSK and Astellas Pharma Inc., the FDA's acceptance of the NDA triggers milestone payments to XenoPort of $23 million in the aggregate.

Solzira is a new chemical entity that is designed to improve upon the pharmacokinetics of gabapentin by taking advantage of high-capacity transport mechanisms in the gastrointestinal tract to improve absorption.

XenoPort is a biopharmaceutical company focused on developing a portfolio of internally discovered product candidates that utilize the body's natural nutrient transport mechanisms to improve the therapeutic benefits of existing drugs.