Amgen Inc.’s biosimilar to top-selling drug Humira was approved Friday by the U.S. Food and Drug Administration. The Thousand Oaks biotech’s version of pharma giant AbbVie Inc.’s Humira, which brought in $14 billion in revenue in 2015, was expected to get the greenlight after an advisory committee voted 26-0 in favor of approval in July. Just last month Chicago-based AbbVie filed a lawsuit claiming patent infringement against Amgen’s biosimilar to the popular arthritis medication in an attempt to block the competition. Biosimilars are highly comparable to their original counterparts but cannot be exact replicas as they are made in living cells. Amgen shares closed down 82 cents, or less than 1 percent, to $174.80 on the Nasdaq.