Exhibit 4.1 UNIT PURCHASE AGREEMENT Gensia Sicor Inc. 19 Hughes Irvine, California 92618 Ladies & Gentlemen: The undersigned purchaser (the "Purchaser") hereby confirms its agreement with you as follows: 1. This Unit Purchase Agreement (the "Purchase...Unit Purchase Agreement • August 13th, 1999 • Sicor Inc • Pharmaceutical preparations • California
