In a small legal victory for Amgen Inc., a U.S. District Court judge in Delaware has denied a motion to dismiss a lawsuit filed by Amgen against Ariad Pharmaceuticals Inc.

Thousand Oaks-based Amgen filed the lawsuit seeking a judgment that confirms its arthritis treatments, Enbrel and Kineret, do not infringe on Ariad’s patents for treating arthritis.

Since the court did not dismiss the suit, which was originally filed in April, the case will move forward. Enbrel generates more than $1 billion in annual sales for Amgen.