Exhibit 10.25.2

                              AMENDMENT NO. 2 TO

              DISTRIBUTION AND MARKETING COLLABORATION AGREEMENT


This Amendment No. 2 to Ethyol(R) (amifostine) Distribution and Marketing
Collaboration Agreement (the "Amendment") is entered into as of the 3rd day of
February, 1997 between U.S. Bioscience, Inc. ("USB") and ALZA Corporation
("ALZA").

 
                                   RECITALS


     A.   USB and ALZA entered into a Distribution and Marketing Collaboration
Agreement (as amended prior to the date hereof, the "Agreement") on the 12th day
of December, 1995.

     B.   The parties wish to further amend the Agreement as set forth herein.

NOW THEREFORE, the parties agree as follows:

     1.   Terms.  Capitalized terms used in this Amendment shall have the same
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meanings as in the Agreement, unless otherwise defined herein.

     2.   1997 and 1998 Marketing and Certain Clinical Expenses.  The following
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is added as a new Section 4.4A of the Agreement:

     "From time to time during the calendar years 1997 and 1998, at the request
     of ALZA, USB will provide financial support for marketing, and clinical
     studies, for the PRODUCT, in an aggregate cost of $3.6 million. Such
     spending shall be in the form of (i) direct payments by USB to third
     parties in connection with such activities; or (ii) reimbursement to ALZA
     for out-of-pocket expenditures for such activities, as requested by ALZA.
     All expenditures pursuant to this Section 4.4A shall be approved by the
     COLLABORATION COMMITTEE in accordance with Article II of this AGREEMENT,
     and ALZA shall have the tie-breaking vote. Expenditures pursuant to this
     Section 4.4A shall be designated as such, in writing, by ALZA. The parties
     expressly acknowledge that financial support that USB is obligated to
     provide pursuant to the first sentence of this Section 4.4A is in addition
     to, and is not intended to relieve or reduce, the obligations of ALZA to
     make certain minimum expenditures with respect to (a) advertising and
     promotion expenses pursuant to Section 4.4 of this AGREEMENT and (b)
     DEVELOPMENT COSTS for ALZA's RESEARCH DEVELOPMENT program under Section
     5.2(b) of this AGREEMENT."

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     3.   Public Announcements.  A new paragraph (d) is added to Section 10.6 of
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the Agreement as follows:
 
     "Subject to Section 10.6(b) of this AGREEMENT, each party shall provide the
     other party with drafts of its proposed public statements in the form of
     press releases, presentation slides and portions of shareholder mailings,
     in each case referring to the PRODUCT, the other party or this AGREEMENT,
     at least two business days in advance (unless extenuating circumstances, in
     the reasonable discretion of the disclosing party, require less) of their
     distribution. Each party shall advise the other, in advance, of any
     securities, financial analyst and similar public conferences or meetings at
     which such party intends to include information concerning the PRODUCT as a
     primary focus of the conference or meeting, and shall provide the other
     party, at least two business days in advance (unless extenuating
     circumstances, in the reasonable discretion of the disclosing party,
     requires less) with the proposed presentation material for review and
     comment. Each party shall duly consider comments made by the other party
     with respect to any of the public statements, slides, documents and
     materials described above. The parties shall use reasonable efforts to
     ensure that their respective public statements concerning this AGREEMENT
     and/or the PRODUCT are consistent with those of the other party."

     4.   Except as specifically set forth above, the Agreement remains in full
force and effect as originally executed.

IN WITNESS WHEREOF, the parties have executed this Amendment No. 2 as of this
3rd day of February, 1997.



ALZA CORPORATION                         U.S. BIOSCIENCE, INC.


By:        /s/ Ernest Mario              By:      /s/ C. Boyd Clarke
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Title:     Chief Executive Officer       Title:    President and COO
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