Exhibit 10.25 ------------- February 12, 1998 Leonard S. Schleifer, M.D., Ph.D. President and Chief Executive Officer, Regeneron Pharmaceuticals, Inc. 777 Old Saw Mill River Road Tarrytown, New York 10591-6707 Dear Len: As you know, the Board of...Regeneron Pharmaceuticals Inc • March 26th, 1998 • Pharmaceutical preparations • New York
