WASHINGTON - In an effort to overturn a judicial verdict that challenges its lucrative Epogen (EPO) franchise, Amgen Inc. is pushing hard for Congress to enact legislation in the next three weeks that could alter the intellectual property landscape in which most biotech and pharmaceutical products are developed.

AMGN has been circulating proposals on Capitol Hill and to trade associations that are intended to close what the company calls a "loophole" in the Waxman-Hatch Amendments that could help Transkaryotic Therapies Inc. (TKTX) to market a version of EPO long before AMGN's patents on its flagship product expire (see BioCentury, April 21, 1997).