SUMMIT, NJ ( TheStreet) -- Celgene's ( CELG) top-selling cancer drug Revlimid passed a closely watched European safety review, the company said Friday. European regulators concluded that Revlimid's benefit for patients with multiple myeloma outweighed the drug's risks. The European Medicines Agency initiated the so-called Article 20 safety review of Revlimid based on data showing that long-term use of Revlimid in multiple myeloma patients may increase the number of secondary cancers even as the drug prolongs patient survival. Revlimid is approved in multiple myeloma for patients who no longer respond to prior treatments, but Celgene is hoping to expand Revlimid's approval so that the drug will be used longer and in earlier stages of the bone marrow cancer. With the Article 20 review concluded in Celgenge's favor, European regulators are next expected to act on expanding Revlimid into earlier stages of multiple myeloma. Celgene plans to seek U.S. approval for expanded Revlimid use later this year. Celgene relies on Revlimid as the most important growth driver in its cancer drug franchise. Revlimid sales in the second quarter increased 35% to $795 million, handily beating expectations and spurring Celgene to raise its 2011 Revlimid sales forecast to a range of $3.15 billion to $3.25 billion. Celgene shares closed Thursday at $63.54. --Written by Adam Feuerstein in Boston. >To contact the writer of this article, click here: Adam Feuerstein. >To follow the writer on Twitter, go to http://twitter.com/adamfeuerstein. >To submit a news tip, send an email to: email@example.com.