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                                                                 Exhibit 10.11.1

                      AMENDMENT TO MANUFACTURING AGREEMENT


         This amendment ("AMENDMENT"), dated April 12, 1995, is by and between
U.S. Bioscience, Inc. ("USB"), a corporation organized and existing under the
laws of the state of Delaware and Applied Analytical Industries, Inc., a
corporation organized and existing under the laws of Delaware, having a place of
business at 1206 North 23rd Street, Wilmington, North Carolina 28405 ("AAI").

         WHEREAS, USB and AAI entered into a Manufacturing Agreement dated
January 1995 (the "Agreement"), relating to the manufacture of Hexalen(R)
(Altretamine);

         WHEREAS, USB and AAI desire to amend certain provisions of the
Agreement as hereinafter provided; and

         NOW, THEREFORE, in consideration of the mutual promises contained
herein and intending to be legally bound hereby, the parties hereby agree as
follows:



         1. Definitions: Except as otherwise specifically provided herein, all
capitalized terms used herein and not defined herein shall have the meaning
assigned to such terms in the Agreement.

         2. Inspection: Section 8.2 of the Agreement shall be amended by
deleting Section 8.2 in its entirety and in its place inserting the following
Section 8.2:

                  "8.2 INSPECTION. USB and those of its distributors, licensees
                  and sub-licensees and their respective affiliates with rights
                  to market or sell the PRODUCT identified to AAI by USB and
                  satisfactory to AAI (collectively, the "USB Affiliates"), upon
                  reasonable notice, shall have the right, at their sole cost
                  and expense, to conduct periodic inspections of AAI's
                  facilities to inspect and observe AAI's manufacturing, quality
                  control and quality assurance procedures. AAI shall make
                  available to USB and the USB Affiliates during on-site
                  inspection all records and documentation addressing the
                  PREPARATION and quality control of the PRODUCT. AAI shall also
                  provide USB and the USB Affiliates, at their request, copies
                  of such records during such inspection at the sole cost and
                  expense of the party initiating the inspection."


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         3. Effect of Amendment: Other than the specific amendment set forth
above, all other terms and conditions of the Agreement shall remain in full
force and effect. This Amendment embodies the full and complete understanding of
the parties hereto with respect to the matters addressed herein and supersedes
all prior understandings and agreements whether oral or written.

         IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized officers to execute this Agreement.

U.S. BIOSCIENCE, INC.


BY:
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TITLE:  Senior Vice President, Pharmaceutical Operations
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DATE:  April 11, 1995
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APPLIED ANALYTICAL INDUSTRIES, INC.


BY:
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TITLE:
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DATE:
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