Shares of XenoPort (XNPT) surged more than 60% on Thursday as the Food and Drug Administration announced approval of Horizant, a drug the company developed in conjunction with GlaxoSmithKline PLC (GSK) designed to treat restless leg syndrome. 

In November, XenoPort purchased all rights to Horizant sold outside of the U.S. from GlaxoSmithKline.

The news comes after the FDA opted not to approve Horizant last year following a laboratory link to cancer in rats. However, late Wednesday the drug was approved and now stands as the first drug to ever be approved for treatment of restless legs syndrome. The companies are also looking at the drug as a possible treatment for the pain felt in conjunction with shingles.

The run up in the shares was a far cry from the 66% drop the company experienced in February of last year when the FDA denied approval of Horizant after viewing preclinical studies.

XenoPort has the rights to develop and sell Horizant to Astellas Pharma in Japan and five other Asian countries, and will sell to GlaxoSmithKline in the U.S. The company also has another drug in development, XP21279, which is in Phase II trials for treatment of Parkinson’s disease. The company is expected to report results in the third quarter of 2011.