A New Jersey U.S. District Judge has approved a $165 million settlement in a class-action lawsuit against Schering-Plough Corp., that accused the drug maker of failing to adequately disclose “serious and widespread deficiencies” in manufacturing and quality operations of the drug Clarinex between May 2000 and February 2001. When the company announced in 2001 that the FDA had postponed the approval of Clarinex, its stock fell 15 percent. Bloomberg reported that the settlement could affect as many as 280,000 investors