The American Antitrust Institute has taken a stand against Israel-based Teva Pharmaceuticals Inc. (TEVA)'s $40.5 billion deal to acquire the generics operation of Allergan plc (AGN). The deal, which would combine the No. 1 and No. 3 generic drug marketers in the U.S., is being examined for competition issues in the U.S. by the Federal Trade Commission. The merger watchdog sent a 12-page letter to FTC Chairwoman Edith Ramirez outlining the group's objections to the merger. Although the AAI didn't specifically call on the commission to challenge the deal in court, the clear implication of its analysis is that the transaction should be blocked, The Deal's William McConnell reported. 'A divestiture remedy for the competitive issues raised by this merger is unlikely to fully restore competition lost by the proposed merger,' according to the letter, which was signed by William Comanor, a professor in the economics and health policy departments at the University of California, and AAI President Diana Moss. The Deal's Senior Reporter Lisa Allen has the details from New York.