EXHIBIT 10.25 477 MARCH ROAD TEL: + 1 613 592 2790 OTTOWA, ON K2K 1X8 FAX: + 1 613 592 6937 CANADA www.mds.nordion.com (MDS NORDION LOGO) April 27, 2006 Molecular Insight Pharmaceuticals, Inc. 160 Second Street Cambridge, Massachusetts 202142 USA Dear...