Swiss drug maker Serono Laboratories agreed to pay $704 million and pleaded guilty yesterday to boosting sales of Serostim—used to treat HIV-med-related wasting—by offering docs free trips to the south of France for writing Serostim scrips and manipulating atest for AIDS patients. Serono’s payout, the third largest health-care fraud settlement in the U.S., follows a year in which the company’s sales totaled $2.46 billion.