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                                                                    EXHIBIT 10.1



                                 AMENDMENT NO. 1

                                       TO

                         COMMON STOCK PURCHASE AGREEMENT







                          DATED AS OF FEBRUARY 20, 2001

                                     BETWEEN

                              CV THERAPEUTICS, INC.

                                       AND

               ACQUA WELLINGTON NORTH AMERICAN EQUITIES FUND, LTD.




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                  AMENDMENT NO. 1, dated as of February 20, 2001 (this
"Amendment"), between CV Therapeutics, Inc., a Delaware corporation (the
"Company") and Acqua Wellington North American Equities Fund, Ltd., a company
organized under the laws of the Commonwealth of The Bahamas (the "Purchaser"),
to the Common Stock Purchase Agreement ( the "Purchase Agreement"), dated as of
August 7, 2000 between the Company and the Purchaser.



                              W I T N E S S E T H :
                              ---------------------


                  WHEREAS, the Purchase Agreement provides for the issuance and
sale by the Company to the Purchaser of shares of the Company's common stock,
par value $0.001 (the "Common Stock"), pursuant to certain Draw Downs (as
defined therein) in accordance with the terms and conditions set forth therein;
and

                  WHEREAS, the parties now wish to amend the Purchase Agreement
as set forth in this Amendment;

                  NOW, THEREFORE, in consideration of the foregoing and the
mutual covenants contained herein, the parties hereby agree as follows:

          Section 1. AMENDMENTS TO THE PURCHASE AGREEMENT.

                  1.1.  Section 1.1(k) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 1.1(k):

                        "(k)  "COMMISSION FILINGS" means the Registration
                  Statements on Form S-3 Nos. 333-41718 and 333-53206
                  and all other filings made by the Company with the Commission
                  prior to or after the Effective Date pursuant to the Exchange
                  Act."

                  1.2.  Section 1.1(hh) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 1.1(hh):

                        "(hh) "REGISTRATION STATEMENT" shall mean the
                  registration statements on Form S-3, Commission File Numbers
                  333-41718 and 333-53206 under the Securities Act, filed with
                  the Securities and Exchange Commission for the registration of
                  the Shares, as such Registration Statement may be amended from
                  time to time."

                  1.3.  Section 2.1 of the Purchase Agreement is hereby amended
by deleting the section in its entirety and substituting in lieu thereof the
following Section 2.1.:

                        "Section 2.1 PURCHASE AND SALE OF STOCK. Subject to
                  the terms and conditions of this Agreement, the Company shall
                  issue and sell to the Purchaser and the Purchaser shall
                  purchase from the Company during the Investment Period up to
                  $220,000,000 of Common Stock based on up to thirty-six (36)
                  Draw Downs during the Investment Period as provided in Section
                  6.1 hereof. Subject to the terms and conditions of this
                  Agreement, the Company in its discretion may also grant the
                  Purchaser one (1) or more Call Options which may be exercised
                  during any Draw Down Pricing Period, as provided in Section
                  6.2 hereof. The aggregate dollar amount of all


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                  Draw Down Amounts and Call Option Amounts pursuant to the
                  terms and conditions of this Agreement shall not exceed
                  $220,000,000."

                  1.4.  Section 6.1(a) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 6.1(a):

                        "(a)  The Company may, in its sole discretion, issue a
Draw Down Notice (as defined in Section 6.1(j) hereof) for a specified Draw Down
Amount Requested of up to (i) $6,000,000 if the Threshold Price for the Draw
Down Amount as set forth in such draw Down Notice is equal to or greater than
$20.00 and less than $35.00, (ii) $8,000,000 if the Threshold Price for the Draw
Down Amount as set forth in such Draw Down Notice is equal to or greater than
$35.00 or (iii) such other amount mutually agreed upon by the Purchaser and the
Company, which Draw Down the Purchaser will be obligated to accept. The date the
Company issues any Draw Down Notice in accordance with this Section 6.1 shall be
a "Draw Down Exercise Date" for purposes of this Agreement."

                  1.5.  Section 6.1(f) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 6.1(f):

                        "(f)  There shall be a maximum of thirty-six (36) Draw
                  Downs during the Investment Period."

                  1.6.  Section 6.1(g) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 6.1(g):

                        "(g)  At the end of each Draw Down Pricing Period, the
                  Purchaser's total Draw Down commitment under this Agreement
                  (which equalled $120,000,000 on the Effective Date and equals
                  $220,000,000 as amended) shall be reduced by the total amount
                  of the Draw Down Amount and the Call Option Amount, if any,
                  for such Draw Down Pricing Period."

                  1.7.  Section 6.1(j) of the Purchase Agreement is hereby
amended by deleting the last sentence in the section in its entirety and
substituting in lieu thereof the following sentence:

                        "Unless the Company and the Purchaser mutually agree
                  otherwise, at no time shall the Purchaser be required to
                  purchase more than $8,000,000 of the Common Stock for a given
                  Draw Down Pricing Period (excluding the Common Stock purchased
                  pursuant to a Call Option)."

                  1.8.  Section 6.2(a) of the Purchase Agreement is hereby
amended by deleting the section in its entirety and substituting in lieu thereof
the following Section 6.2(a):

                        "(a)  The Company may, in its sole discretion, grant to
                  the Purchaser the right to exercise one (1) or more Call
                  Options during each Draw Down Pricing Period for a specified
                  Call Option Amount Requested; provided, however, that (i) each
                  Call Option Amount Requested shall be for a minimum of
                  $50,000, (ii) the aggregate total of all Call Option Amounts
                  Requested during a Draw Down Pricing Period may not exceed
                  $8,000,000, or such other amount as may be agreed upon by the
                  Company and the Purchaser, and (iii) the Call Option Amount on
                  any Trading Day during the Draw Down Pricing Period may not
                  exceed $1,000,000. The Call Option Amount Requested and the
                  Call Option Threshold Price shall be set forth in the Draw
                  Down Notice."


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                  1.9.  Section 7.1 of the Purchase Agreement is hereby amended
by deleting clause (i) of the section in its entirety and substituting in lieu
thereof the following clause:

                        "(i)  forty (40) consecutive months from the Effective
                  Date (the "INVESTMENT PERIOD")"

          Section 2. MISCELLANEOUS.

                  2.1.  LIMITED EFFECT. Except as expressly amended and modified
by this Amendment, all of the provisions and covenants of the Purchase Agreement
are and shall continue to remain in full force and effect in accordance with the
terms thereof.

                  2.2.  COUNTERPARTS. This Amendment may be executed by one or
more of the parties hereto in any number of separate counterparts, and all of
said counterparts taken together shall be deemed to constitute one and the same
instrument.

                  2.3.  GOVERNING LAW. This Amendment shall be governed by and
construed in accordance with the internal laws of the State of New York, without
giving effect to the choice of law provisions.





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                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be duly executed and delivered by their respective authorized
officers as of the date first above written.

                                     CV THERAPEUTICS, INC.


                                     By:     /s/ DANIEL K. SPIEGELMAN
                                        ---------------------------------------
                                        Name: Daniel K. Spiegelman
                                        Title: Senior Vice President and Chief
                                               Financial Officer


                                      ACQUA WELLINGTON NORTH AMERICAN EQUITIES
                                      FUND, LTD.

                                     By: /s/ ANTHONY L. M. INDER RIEDEN
                                       ----------------------------------------
                                        Name: Anthony L. M. Inder Rieden
                                        Title: Director