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                                                                   EXHIBIT 10.73
                                LICENSE AGREEMENT
                                 AMENDMENT NO. 2


         THIS AMENDMENT NO. 2 TO THE LICENSE AGREEMENT ("Second Amendment") is
made and entered into effective as of November 30, 1999, ("Second Amendment
Date") by and between SYNTEX (U.S.A.) INC. ("Syntex") having offices at 3401
Hillview Avenue, Palo Alto, Califomia 94304, and CV THERAPEUTICS, INC. ("CVT")
having an address at 3172 Porter Drive, Palo Alto, California 94304. Capitalized
Terms used in the Amendment that are not otherwise defined herein shall have the
same meanings as such terms are defined in the License Agreement.

                                    RECITALS

         Syntex and CVT entered into the License Agreement effective March 27,
1996 ("License Agreement") and entered into an Amendment to the License
Agreement effective July 3, 1997 ("Amendment"). The License Agreement as amended
by the Amendment and this Amendment No. 2 shall constitute the "Agreement."

         The parties now wish to amend the Agreement to change the milestones
and payments associated with those milestones.

         NOW, THEREFORE, in consideration of the mutual promises contained
herein, the sufficiency of which is hereby acknowledged, Syntex and CVT now wish
to amend the Agreement as follows:

         1.   DELETION OF SECTION 4.5 AND EXHIBIT B.  Section 4.5 of and
Exhibit B to the License Agreement are hereby deleted in their entirety.

         2.   AMENDMENT OF SECTION 5.1(b).  Section 5.1(b) of the License
Agreement is hereby amended and replaced in its entirety with the following:

                  (1)      NDA FILING.  CVT shall use its best efforts to file
                           an NDA for a Licensed Product no later than June 1,
                           2001.

                  (2)      FIRST NDA PAYMENT. If the first approval of an NDA or
                           equivalent in one of the Major Market Countries
                           occurs before May 1, 2002, CVT shall pay to Syntex on
                           or before March 31, 2005 seven million United States
                           dollars (US $7,000,000), plus all accrued interest
                           thereon (interest shall accrue on the payment from
                           the date of approval of such NDA or equivalent until
                           the date payment is made at the rates set forth in
                           the Interest Table). If the first approval of an NDA
                           or equivalent in one of the Major Market Countries
                           occurs after May 1, 2002, CVT shall pay to Syntex on
                           or before March 31, 2005 seven million United States
                           dollars (US $7,000,000), plus all accrued interest
                           thereon (interest shall accrue on the payment from
                           May 1, 2002 until the date payment is made at, the
                           rates set forth in the Interest Table).

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                  (3)      SECOND NDA PAYMENT. In addition to the payment in
                           Section 5.1(b)(2) above, if the second approval of an
                           NDA or equivalent in one of the Major Market
                           Countries occurs before May 1, 2004, CVT shall pay to
                           Syntex on or before March 31, 2006 seven million
                           United States dollars (US $7,000,000), plus all
                           accrued interest thereon (interest shall accrue on
                           the payment from the date of approval of such NDA or
                           equivalent until the date payment is made at the
                           rates set forth in the Interest Table). If the second
                           approval of an NDA or equivalent in one of the Major
                           Market Countries occurs after May 1, 2004 but before
                           March 31, 2006, CVT shall pay to Syntex on or before
                           March 31, 2006 seven million United States dollars
                           (US $7,000,000), plus all accrued interest thereon
                           (interest shall accrue on the payment from May 1,
                           2004 until the date payment is made at the rates set
                           forth in the Interest Table). If the second approval
                           of an NDA or equivalent in one of the Major Market
                           Countries has not occurred by March 31, 2006, CVT
                           shall pay to Syntex on or before March 31, 2006 three
                           million United States dollars (US $3,000,000). If,
                           after March 31, 2006, CVT receives the second
                           approval of an NDA or equivalent in one of the Major
                           Market Countries, CVT shall pay to Syntex four
                           million United States dollars (US $4,000,000) within
                           thirty (30) days of the date of such second NDA or
                           equivalent approval,

                  (4)      For purpose of this Section 5.1, "Major Market
                           Countries" shall mean the United States, France,
                           Germany, Italy and the United Kingdom.

                  (5)      For purpose of this Section 5.1 "Interest Table"
                           shall mean the following interest table.

<TABLE>
<CAPTION>
                           ----------------------------------- ---------------------------------
                                      TIME PERIOD                    ANNUAL INTEREST RATE
                                    (CALENDAR YEAR)
                           ----------------------------------- ---------------------------------
                           <S>                                 <C>

                                          2000                               13%
                           ----------------------------------- ---------------------------------
                                          2001                               14%
                           ----------------------------------- ---------------------------------
                                          2002                               15%
                           ----------------------------------- ---------------------------------
                                          2003                               16%
                           ----------------------------------- ---------------------------------
                                          2004                               18%
                           ----------------------------------- ---------------------------------
                                          2005                               20%
                           ----------------------------------- ---------------------------------
</TABLE>

         3.   AMENDMENT OF SECTION 11.3.  Section 11.3 of the License
Agreement is hereby amended and replaced in its entirety with the following:

                                       2
<PAGE>


                  11.3     Failure by one party to comply with any of its
                           respective obligations contained in this Agreement
                           shall entitle the other party to give the party in
                           default written notice of such default. If such
                           default is not remedied within ninety (90) days after
                           receipt of such notice (or thirty (30) days in the
                           event of non-payment of fees other than those
                           contained in Section 5.1(b)), the notifying party
                           shall be entitled to terminate this Agreement by
                           giving notice with immediate effect The right of
                           either party to terminate this Agreement as provided
                           hereinabove shall not be affected in any way by its
                           waiver of or failure to take actions with respect to
                           any previous default. In such cases of breach by CVT,
                           all licenses from CVT to Syntex as set forth below in
                           Section 11.4 for the case of any early termination
                           shall be royalty free, and CVT shall provide Syntex
                           all of the information required by Section 11.4 in
                           the event of early termination or breach of this
                           Agreement by CVT. Notwithstanding anything else
                           contained in this Agreement, if CVT fails to make any
                           payment under Section 5.1(b) on or prior to the due
                           date, Syntex may in its sole discretion terminate
                           this Agreement with immediate effect. If there is any
                           BONA FIDE dispute between the parties regarding the
                           right of termination based on failure by CVT to make
                           a milestone or royalty payment (other than those
                           contained in Section 5.1(b)), as the case may be, the
                           disputed royalty or milestone payment shall be paid
                           into an interest bearing account by CVT where it
                           shall remain during the pendency of the dispute, and
                           upon resolution of the dispute, paid, with
                           accumulated interest, to the prevailing party. For
                           purposes of Section 5.1, the payment shall be deemed
                           paid on the date such payment is paid into the
                           interest bearing account.

         4.   AMENDMENT OF ARTICLE 11.  A new section 2.6 is added to the
Agreement as follows:

                  2.6      CVT may grant rights to CVT Patents and Know-How
                           and/or Syntex Patents and Know-How to any Veterans
                           Administration hospitals at which CVT conducts
                           clinical trials of the Compound, provided the grant
                           of rights is at least as restrictive as the following
                           language:

                           Rights to any information, inventions, or discoveries
                           (whether patentable, copyrightable or not),
                           innovations, suggestions, ideas, communications, and
                           reports (collectively "Inventions"), conceived,
                           reduced to practice, made or developed by the
                           Principal Investigator or the Department of Veterans
                           Affairs ("DVA') as a result of conducting a Study are
                           controlled by Federal Law (35 U.S.C. 200-212, 37 CFR
                           501, 38 CFR 1.650-666). However, if DVA of Principal
                           Investigator obtains ownership of such Inventions
                           arising from research conducted under a Study,
                           Sponsor shall have the option to obtain a sole and
                           exclusive worldwide license to all of DVA's and/or
                           Principal Investigator's rights any such Invention.
                           DVA and Principal Investigator shall promptly notify
                           Sponsor in writing of any such Invention ("Notice").
                           Within one hundred and eighty (180) days after

                                       3
<PAGE>


                           Sponsor receives Notice, Sponsor and DVA and/or
                           Principal Investigator shall enter into good faith
                           negotiations directed to an agreement whereby Sponsor
                           acquires sole and exclusive worldwide rights to such
                           Invention, subject to the right of the United States
                           to retain an irrevocable, royalty-free right to use
                           the Invention throughout the United States. The
                           license agreement shall contain reasonable terms and
                           conditions which are usual and customary for
                           pharmaceutical products at a like stage of
                           development, which shall include a royalty for such
                           license based upon the relative contributions to the
                           Invention by the Principal Investigator and the
                           commercial value of such Invention. In the event that
                           the parties cannot agree, after good faith
                           negotiations, to an exclusive license agreement, then
                           Sponsor shall have a right of first refusal to accept
                           any terms offered to a third party for rights to the
                           Invention.

                           The granting of such rights by CVT to the Veterans
                           Administration hospitals shall not constitute a
                           breach by CVT of this Agreement, and such rights
                           shall not terminate upon termination of the
                           Agreement. The grant of such rights to the Veterans
                           Administration hospitals shall not be limited to
                           Cardiovascular Indications, but shall apply to any
                           indications for such inventions.

         5.   FULL FORCE AND EFFECT.  This Amendment No, 2 amends the terms
of the License Agreement and the Amendment and is deemed incorporated into,
and governed by all the other terms of, the License Agreement and Amendment.
The provisions of the License Agreement, as amended by the Amendment and this
Amendment No. 2, remain in full force and effect.

         IN WITNESS WHEREOF, the parties have executed this Amendment to be
effective as of the Second Amendment Date.

<TABLE>
<CAPTION>

SYNTEX (U.S.A.) INC.                                         CV THERAPEUTICS, INC.
<S>                                                          <C>
By:                                                          By:
    -------------------------------------------------             -------------------------------------------------
Name:          JAMES N. WOODY                                Name:          LOUIS LANGE
    -------------------------------------------------             -------------------------------------------------
Title:         PRESIDENT                                     Title:         CHAIRMAN AND CEO
    -------------------------------------------------             -------------------------------------------------
Date:          12/21/99                                      Date:          12/9/99
    -------------------------------------------------             -------------------------------------------------

</TABLE>
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