Biovail announced Friday that it has filed a federal lawsuit against the FDA to prevent the agency from approving a generic form of antidepressant Wellbutrin XL before ruling on a citizen petition the firm filed with the agency in December 2005. The company is reported to be seeking a temporary restraining order and preliminary injunction requiring FDA to address the petition before approving a generic version of Wellbutrin XL, giving Biovail time to prepare for a countersuit. The petition “is intended to protect the public against the potentially harmful effects of generic versions of Wellbutrin XL that may not, in fact, be bioequivalent to Biovail’s branded product, or that may be misleadingly labeled, under the criteria set forth in,” Biovail said in a statement. Wellbutrin XL garnered $1.2 billion in global sales in 2005, representing 40% of Biovail’s total revenue. Biovail jointly markets Wellbutrin XL with GlaxoSmithKline. The main US patent on Wellbutrin XL is set to expire on Aug. 28.