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                                                                EXHIBIT 4.3

No. CWA-101                     Right to Purchase 198,300 Shares of Common Stock
                                of Axys Pharmaceuticals, Inc.


                           AXYS PHARMACEUTICALS, INC.

                     COMMON STOCK PURCHASE WARRANT, CLASS A


               AXYS PHARMACEUTICALS, INC., a Delaware corporation, hereby
certifies that, for value received, DELTA OPPORTUNITY FUND, LTD. or registered
assigns (the "Holder"), is entitled, subject to the terms set forth below, to
purchase from the Company at any time or from time to time before 5:00 p.m., New
York City time, on the Expiration Date (such capitalized term and all other
capitalized terms used herein having the respective meanings provided herein),
198,300 fully paid and nonassessable shares of Common Stock at a purchase price
per share equal to the Purchase Price. The number of such shares of Common Stock
and the Purchase Price are subject to adjustment as provided in this Warrant.

               As used herein the following capitalized terms, unless the
context otherwise requires, have the following respective meanings:

               "Aggregate Purchase Price" means at any time an amount equal to
        the product obtained by multiplying (x) the Purchase Price times (y) the
        number of shares of Common Stock for which this Warrant may be exercised
        at such time.

               "AMEX" means the American Stock Exchange, Inc.

               "Board of Directors" means the Board of Directors of the Company.

               "Business Day" means any day other than a Saturday, Sunday or
        other day on which commercial banks in The City of New York are
        authorized or required by law to remain closed.

               "Common Stock" includes the Company's Common Stock, par value
        $.001 per share, and the related Preferred Share Purchase Rights (and
        any similar rights issued with respect to the Common Stock) as
        authorized on the date hereof, and any other securities into which or
        for which the Common Stock or the related Preferred Share Purchase
        Rights (and any similar rights issued with respect to the Common Stock)
        may be converted or exchanged pursuant to a plan of recapitalization,
        reorganization, merger, sale of assets or otherwise and any stock (other
        than Common Stock) and other securities

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        of the Company or any other Person which the Holder at any time shall be
        entitled to receive, or shall have received, on the exercise of this
        Warrant, in lieu of or in addition to Common Stock.

               "Common Stock Equivalents" means any warrant, option,
        subscription or purchase right with respect to shares of Common Stock,
        any security convertible into, exchangeable for, or otherwise entitling
        the holder thereof to acquire, shares of Common Stock or any warrant,
        option, subscription or purchase right with respect to any such
        convertible, exchangeable or other security.

               "Common Stock Purchase Agreement" means the Common Stock Purchase
        Agreement, dated as of July 21, 2000, between the Company and Acqua
        Wellington North American Equities Fund, Ltd., as in effect on the
        earliest date of first issuance of any of the Notes.

               "Company" shall include Axys Pharmaceuticals, Inc., a Delaware
        corporation, and any corporation that shall succeed to or assume the
        obligations of Axys Pharmaceuticals, Inc. hereunder in accordance with
        the terms hereof.

               "Current Fair Market Value" means when used with respect to the
        Common Stock as of a specified date with respect to each share of Common
        Stock, the average of the closing prices of the Common Stock sold on all
        securities exchanges (including the Nasdaq and the Nasdaq SmallCap) on
        which the Common Stock may at the time be listed, or, if there have been
        no sales on any such exchange on such day, the average of the highest
        bid and lowest asked prices on all such exchanges at the end of such
        day, or, if on such day the Common Stock is not so listed, the average
        of the representative bid and asked prices quoted in the NASDAQ System
        as of 4:00 p.m., New York City time, or, if on such day the Common Stock
        is not quoted in the NASDAQ System, the average of the highest bid and
        lowest asked price on such day in the domestic over-the-counter market
        as reported by the National Quotation Bureau, Incorporated, or any
        similar successor organization, in each such case averaged over a period
        of ten Trading Days consisting of the day as of which the Current Fair
        Market Value of Common Stock is being determined (or if such day is not
        a Trading Day, the Trading Day next preceding such day) and the nine
        consecutive Trading Days prior to such day. If on the date for which
        Current Fair Market Value is to be determined the Common Stock is not
        listed on any securities exchange or quoted in the NASDAQ System or the
        over-the-counter market, the Current Fair Market Value of Common Stock
        shall be the highest price per share which the Company could then obtain
        from a willing buyer (not an employee or director of the Company at the
        time of determination) in an arms'-length transaction

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        for shares of Common Stock sold by the Company, from authorized but
        unissued shares, as determined in good faith by the Board of Directors.

               "Expiration Date" means October 1, 2004.

               "Issuance Date" means the date of original issuance of this
Warrant.

               "Nasdaq" means the Nasdaq National Market.

               "Nasdaq SmallCap" means the Nasdaq SmallCap Market.

               "1934 Act" means the Securities Exchange Act of 1934, as amended.

               "1933 Act" means the Securities Act of 1933, as amended.

               "Note Purchase Agreement" means the Note Purchase Agreement,
        dated as of September 20, 2000, by and between the Company and the
        original Holder of this Warrant.

               "Notes" means any of the 8% Senior Secured Convertible Notes due
        2004 issued by the Company pursuant to the Supplemental Indenture, the
        Note Purchase Agreement or any Other Note Purchase Agreements.

               "NYSE" means the New York Stock Exchange, Inc.

               "Other Note Purchase Agreements" means the several Note Purchase
        Agreements, dated as of the date of the Note Purchase Agreement, by and
        between the Company and the several buyers named therein.

               "Other Securities" means any stock (other than Common Stock) and
        other securities of the Company or any other Person which the Holder at
        any time shall be entitled to receive, or shall have received, on the
        exercise of this Warrant, in lieu of or in addition to Common Stock, or
        which at any time shall be issuable or shall have been issued in
        exchange for or in replacement of Common Stock or Other Securities
        pursuant to Section 4.

               "Other Warrants" means the Common Stock Purchase Warrants (other
        than this Warrant) issued or issuable by the Company pursuant to the
        Note Purchase Agreement and the Other Note Purchase Agreements.

               "Person" means an individual, partnership, corporation, limited
        liability company, trust or unincorporated organization, or a government
        or a governmental agency or political subdivision.

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               "Preferred Share Purchase Rights" means the Preferred Share
        Purchase Rights issued or issuable pursuant to the Rights Agreement (or
        any similar rights hereafter issued by the Company with respect to the
        Common Stock).

               "Purchase Price" means $8.82, subject to adjustment as provided
        in this Warrant.

               "Reorganization Event" means the occurrence of any one or more of
        the following events:

               (i) any consolidation, merger or similar transaction of the
        Company or any Subsidiary with or into another entity (other than a
        merger or consolidation or similar transaction of a Subsidiary into the
        Company or a wholly-owned Subsidiary); or the sale or transfer of all or
        substantially all of the assets of the Company and the Subsidiaries in a
        single transaction or a series of related transactions; or

               (ii) the occurrence of any transaction or event in connection
        with which all or substantially all the Common Stock shall be exchanged
        for, converted into, acquired for or constitute the right to receive
        securities of any other Person (whether by means of a Tender Offer,
        liquidation, consolidation, merger, share exchange, combination,
        reclassification, recapitalization, or otherwise); or

               (iii) the acquisition by a Person or group of Persons acting in
        concert as a partnership, limited partnership, syndicate or group, as a
        result of a tender or exchange offer, open market purchases, privately
        negotiated purchases or otherwise, of beneficial ownership of securities
        of the Company representing 50% or more of the combined voting power of
        the outstanding voting securities of the Company ordinarily (and apart
        from rights accruing in special circumstances) having the right to vote
        in the election of directors.

               "Rights Agreement" means the Rights Agreement, dated as of
        October 8, 1998, between the Company and Harris Trust Company of
        California, as Rights Agent.

               "SEC" means the Securities and Exchange Commission.

               "Subsidiary" means any corporation or other entity of which a
        majority of the capital stock or other ownership interests having
        ordinary voting power to elect a majority of the board of directors or
        other Persons performing similar functions are at the time directly or
        indirectly owned by the Company.

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               "Supplemental Indenture" means the First Supplemental Indenture,
        dated as of September 22, 2000, between the Company and U. S. Bank Trust
        National Association, as Trustee.

               "Tender Offer" means a tender offer, exchange offer or other
        offer by the Company to repurchase outstanding shares of its capital
        stock.

               "Trading Day" means a day on which the national securities
        exchange, the Nasdaq or the Nasdaq SmallCap which then constitutes the
        principal securities market for the Common Stock is open for general
        trading.

               1.     EXERCISE OF WARRANT.

               (a) EXERCISE. This Warrant may be exercised by the Holder in full
at any time or in part from time to time on or before the Expiration Date by (x)
surrendering this Warrant to the Company, (y) giving a subscription form in the
form of EXHIBIT 1 to this Warrant (duly executed by the Holder) to the Company,
and (z) making payment, in cash or by certified or official bank check payable
to the order of the Company, or by wire transfer of funds to the account of the
Company, in any such case, in the amount obtained by multiplying (a) the number
of shares of Common Stock designated by the Holder in the subscription form by
(b) the Purchase Price then in effect. On any partial exercise the Company will
forthwith issue and deliver to or upon the order of the Holder a new Warrant or
Warrants of like tenor, in the name of the Holder or as the Holder (upon payment
by the Holder of any applicable transfer taxes) may request, providing in the
aggregate on the face or faces thereof for the purchase of the number of shares
of Common Stock for which such Warrant or Warrants may still be exercised. The
subscription form may be surrendered by telephone line facsimile transmission to
such telephone number for the Company as shall have been specified in writing to
the Holder by the Company; provided, however, that if the subscription form is
given to the Company by telephone line facsimile transmission the Holder shall
send an original of such subscription form to the Company within ten Business
Days after such subscription form is so given to the Company; provided further,
however, that any failure or delay on the part of the Holder in giving such
original of any subscription form shall not affect the validity or the date on
which such subscription form is so given by telephone line facsimile
transmission. In connection with any exercise of this Warrant, the Holder shall
also furnish to the Company such other documentation as required by applicable
law and reasonably requested by the Company in writing; provided, however, that
any failure or delay on the part of the Holder in furnishing such documentation
shall not affect the validity of the exercise of this Warrant or the date on
which this Warrant shall have been exercised.


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          (b) Net Exercise. Notwithstanding anything to the contrary contained
in Section 1(a), the Holder may elect to exercise this Warrant, in whole or in
part, by receiving shares of Common Stock equal to the net issuance value (as
determined below) of this Warrant, or any part hereof, upon surrender of the
subscription form annexed hereto (duly executed by the Holder) to the Company
(followed by surrender of this Warrant to the Company within three Trading Days
after surrender of such subscription form), in which event the Company shall
issue to the Holder a number of shares of Common Stock computed using the
following formula:

                            X = Y x (A - B)
                                -----------
                                   A

where,

               X =      the number of shares of Common Stock to be issued to
                        the Holder

               Y =      the number of shares of Common Stock as to which this
                        Warrant is to be exercised

               A =      the Current Fair Market Value of one share of Common
                        Stock calculated as of the last Trading Day immediately
                        preceding the exercise of this Warrant

               B =      the Purchase Price

               2. DELIVERY OF STOCK CERTIFICATES, ETC., ON EXERCISE. As soon as
practicable after the exercise of this Warrant and in any event within three
Trading Days thereafter, upon the terms and subject to the conditions of this
Warrant, the Company at its expense (including the payment by it of any
applicable issue or stamp taxes) will cause to be issued in the name of and
delivered to the Holder, or as the Holder (upon payment by the Holder of any
applicable transfer taxes) may direct, a certificate or certificates for the
number of fully paid and nonassessable shares of Common Stock (or Other
Securities) to which the Holder shall be entitled on such exercise, in such
denominations as may be requested by the Holder, plus, in lieu of any fractional
share to which the Holder would otherwise be entitled, cash equal to such
fraction multiplied by the then Current Fair Market Value of one full share,
together with any other stock or Other Securities or any property (including
cash, where applicable) to which the Holder is entitled upon such exercise
pursuant to Section 1 or otherwise. The Company shall pay any taxes and other
governmental charges that may be imposed under the laws of the United States of
America or any political subdivision or taxing authority thereof or therein in
respect of the issue or delivery of shares of Common Stock (or Other Securities)

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or payment of cash upon exercise of this Warrant (other than income taxes
imposed on the Holder). The Company shall not be required, however, to pay any
tax or other charge imposed in connection with any transfer involved in the
issue of any certificate for shares of Common Stock (or Other Securities)
issuable upon exercise of this Warrant or payment of cash to any Person other
than the Holder, and in case of such transfer or payment the Company shall not
be required to deliver any certificate for shares of Common Stock (or Other
Securities) upon such exercise or pay any cash until such tax or charge has been
paid or it has been established to the Company's reasonable satisfaction that no
such tax or charge is due. Upon exercise of this Warrant as provided herein, the
Company's obligation to issue and deliver the certificates for Common Stock
shall be absolute and unconditional, irrespective of the absence of any action
by the Holder to enforce the same, any waiver or consent with respect to any
provision hereof, the recovery of any judgment against any Person or any action
to enforce the same, any failure or delay in the enforcement of any other
obligation of the Company to the Holder, or any setoff, counterclaim,
recoupment, limitation or termination, or any breach or alleged breach by the
Holder or any other Person of any obligation to the Company or any violation or
alleged violation of law by the Holder or any other Person, and irrespective of
any other circumstance which might otherwise limit such obligation of the
Company to the Holder in connection with such exercise. If the Company fails to
issue and deliver the certificates for the Common Stock to the Holder pursuant
to the first sentence of this paragraph as and when required to do so, in
addition to any other liabilities the Company may have hereunder and under
applicable law, the Company shall pay or reimburse the Holder on demand for all
out-of-pocket expenses including, without limitation, fees and expenses of legal
counsel incurred by the Holder as a result of such failure.

               3. ADJUSTMENT FOR DIVIDENDS IN OTHER STOCK, PROPERTY, ETC.;
RECLASSIFICATION, ETC. In case at any time or from time to time on or after the
Issuance Date, all the holders of Common Stock (or Other Securities) shall have
received, or (on or after the record date fixed for the determination of
stockholders eligible to receive) shall have become entitled to receive, without
payment therefor,

               (a) other or additional stock or other securities or property
        (other than cash) by way of dividend, or

               (b) any cash (excluding cash dividends payable solely out of
        earnings or earned surplus of the Company), or

               (c) other or additional stock or other securities or property
        (including cash) by way of spin-off, split-up, reclassification,
        recapitalization, combination of shares or similar corporate
        rearrangement,

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other than (i) additional shares of Common Stock (or Other Securities) issued as
a stock dividend or in a stock-split (adjustments in respect of which are
provided for in Section 5) and (ii) rights or warrants to subscribe for Common
Stock at less than the Current Fair Market Value (adjustments in respect of
which are provided in Section 6), then and in each such case the Holder, on the
exercise hereof as provided in Section 1, shall be entitled to receive the
amount of stock and Other Securities and property (including cash in the cases
referred to in subdivisions (b) and (c) of this Section 3) which the Holder
would hold on the date of such exercise if on the date thereof the Holder had
been the holder of record of the number of shares of Common Stock called for on
the face of this Warrant and had thereafter, during the period from the date
thereof to and including the date of such exercise, retained such shares and all
such other or additional stock and Other Securities and property (including cash
in the case referred to in subdivisions (b) and (c) of this Section 3)
receivable by the Holder as aforesaid during such period, giving effect to all
adjustments called for during such period by Section 4.

               4. EXERCISE UPON A REORGANIZATION EVENT. In case of any
Reorganization Event the Company shall, as a condition precedent to the
consummation of the transactions constituting, or announced as, such
Reorganization Event, cause effective provisions to be made so that the Holder
shall have the right thereafter, by exercising this Warrant (in lieu of the
shares of Common Stock of the Company and Other Securities or property
purchasable and receivable upon exercise of the rights represented hereby
immediately prior to such transaction) to purchase the kind and amount of shares
of stock and Other Securities and property (including cash) receivable upon such
Reorganization Event by a holder of the number of shares of Common Stock that
might have been received upon exercise of this Warrant immediately prior to such
Reorganization Event. Any such provision shall include provisions for
adjustments in respect of such shares of stock and Other Securities and property
that shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Warrant. The provisions of this Section 4 shall apply to
successive Reorganization Events.

               5. ADJUSTMENT FOR CERTAIN EXTRAORDINARY EVENTS. In the event that
on or after the Issuance Date the Company shall (i) issue additional shares of
the Common Stock as a dividend or other distribution on outstanding Common
Stock, (ii) subdivide or reclassify its outstanding shares of Common Stock, or
(iii) combine its outstanding shares of Common Stock into a smaller number of
shares of Common Stock, then, in each such event, the Purchase Price shall,
simultaneously with the happening of such event, be adjusted by multiplying the
Purchase Price in effect immediately prior to such event by a fraction, the
numerator of which shall be the number of shares of Common Stock outstanding
immediately prior to such event and the denominator of which shall be the number
of shares of Common Stock outstanding immediately after such event, and the
product so obtained shall thereafter be the Purchase Price then in effect. The


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Purchase Price, as so adjusted, shall be readjusted in the same manner upon the
happening of any successive event or events described herein in this Section 5.
The Holder shall thereafter, on the exercise hereof as provided in Section 1, be
entitled to receive that number of shares of Common Stock determined by
multiplying the number of shares of Common Stock which would be issuable on such
exercise immediately prior to such issuance by a fraction of which (i) the
numerator is the Purchase Price in effect immediately prior to such issuance and
(ii) the denominator is the Purchase Price in effect on the date of such
exercise.

               6. ISSUANCE OF RIGHTS OR WARRANTS TO COMMON STOCKHOLDERS AT LESS
THAN CURRENT FAIR MARKET VALUE. In case the Company shall on or after the
Issuance Date issue rights or warrants to all holders of its outstanding shares
of Common Stock entitling them to subscribe for or purchase shares of Common
Stock at a price per share less than the Current Fair Market Value on the record
date fixed for the determination of stockholders entitled to receive such rights
or warrants, then

               (a) the Purchase Price shall be adjusted so that the same shall
        equal the price determined by multiplying the Purchase Price in effect
        at the opening of business on the day after such record date by a
        fraction of which the numerator shall be the number of shares of Common
        Stock outstanding at the close of business on such record date plus the
        number of shares which the aggregate offering price of the total number
        of shares so offered would purchase at such Current Fair Market Value,
        and the denominator shall be the number of shares of Common Stock
        outstanding on the close of business on such record date plus the total
        number of additional shares of Common Stock so offered for subscription
        or purchase; and

               (b) the number of shares of Common Stock which the Holder may
        thereafter purchase upon exercise of this Warrant at the opening of
        business on the day after such record date shall be increased to a
        number equal to the quotient obtained by dividing (x) the Aggregate
        Purchase Price in effect immediately prior to such adjustment in the
        Purchase Price pursuant to clause (a) of this Section 6 by (y) the
        Purchase Price in effect immediately after such adjustment in the
        Purchase Price pursuant to clause (a) of this Section 6.

Such adjustment shall become effective immediately after the opening of business
on the day following the record date fixed for determination of stockholders
entitled to receive such rights or warrants. To the extent that shares of Common
Stock are not delivered pursuant to such rights or warrants, upon the expiration
or termination of such rights or warrants, the Purchase Price shall be
readjusted to the Purchase Price which would then be in effect had the
adjustments made upon the issuance of such rights or warrants been made on the
basis of delivery of only

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the number of shares of Common Stock actually delivered and the number of shares
of Common Stock for which this Warrant may thereafter be exercised shall be
readjusted (subject to proportionate adjustment for any intervening exercises of
this Warrant) to the number which would then be in effect had the adjustments
made upon the issuance of such rights or warrants been made on the basis of
delivery of only the number of shares of Common Stock actually delivered. In the
event that such rights or warrants are not so issued, the Purchase Price shall
again be adjusted to be the Purchase Price which would then be in effect if such
record date had not been fixed and the number of shares of Common Stock for
which this Warrant may thereafter be exercised shall again be adjusted (subject
to proportionate adjustment for any intervening exercises of this Warrant) to be
the number which would then be in effect if such record date had not been fixed.
In determining whether any rights or warrants entitle the holder to subscribe
for or purchase shares of Common Stock at less than such Current Fair Market
Value, and in determining the aggregate offering price of such shares of Common
Stock, there shall be taken into account any consideration received for such
rights or warrants, the value of such consideration, if other than cash, to be
determined by the Board of Directors.

               7. ISSUANCE AT LESS THAN CURRENT FAIR MARKET VALUE. (a) In case
at any time on or after the Issuance Date the Company shall issue shares of its
Common Stock or Common Stock Equivalents (collectively, the "Newly Issued
Shares"), other than an issuance pro rata to all holders of its outstanding
Common Stock, at a price below the Current Fair Market Value of the Common Stock
at the time of such issuance, then following such issuance of Newly Issued
Shares the Purchase Price shall be reduced as provided in clause (b) of this
Section 7 and the number of shares of Common Stock which may be issued upon
exercise of this Warrant shall be increased as provided in clause (c) of this
Section 7.

               (b) The reduction in the Purchase Price following any such
adjustment shall be determined by multiplying the Purchase Price immediately
prior to such adjustment by a fraction, of which the numerator shall be the sum
of (1) the number of shares of Common Stock outstanding immediately prior to the
issuance of the Newly Issued Shares (calculated on a fully-diluted basis
assuming the exercise or conversion of all options, warrants, purchase rights or
convertible securities which are exercisable or convertible at the time of the
issuance of the Newly Issued Shares) plus (2) the number of shares of Common
Stock which the aggregate consideration, if any, received by the Company for the
number of Newly Issued Shares would purchase at a price equal to the Current
Fair Market Value of the Common Stock at the time of such issuance, and the
denominator shall be the sum of (X) the number of shares of Common Stock
outstanding immediately prior to the issuance of the Newly Issued Shares
(calculated on a fully-diluted basis assuming the exercise or conversion of all
options, warrants, purchase rights or convertible securities which are
exercisable or convertible at the time of the

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issuance of the Newly Issued Shares) plus (Y) the number of Newly Issued Shares.
The adjustment provided for in this Section 7(b) may be expressed as the
following mathematical formula:

                        (O +(C / FMV))
                  NPP = -------------- x PP
                           (O + N)

where,

C    =  aggregate consideration received by the Company for the Newly Issued
        Shares

N    =  number of Newly Issued Shares

O    =  number of shares of Common Stock outstanding (on a fully diluted basis,
        as described above) immediately prior to the issuance of the Newly
        Issued Shares

FMV  =  Current Fair Market Value of the Common Stock at the time of issuance
        of the Newly Issued Shares

PP   =  Purchase Price immediately prior to the issuance of the Newly Issued
        Shares

NPP  =  Purchase Price immediately after the issuance of the Newly Issued Shares


               (c) If the Purchase Price is reduced in connection with the
issuance of Newly Issued Shares as provided in Section 7(b), then the number of
shares of Common Stock for which this Warrant may thereafter be exercised shall
be increased at the time of such reduction in the Purchase Price to a number
equal to the quotient obtained by dividing (x) the Aggregate Purchase Price in
effect immediately prior to such issuance of Newly Issued Shares by (y) the
Purchase Price in effect immediately after such issuance of Newly Issued Shares
after giving effect to such reduction in the Purchase Price pursuant to Section
7(b).

               (d) Notwithstanding the foregoing, no adjustment shall be made
under this Section 7 by reason of:

               (1) the issuance by the Company of shares of Common Stock pro
rata to all holders of the Common Stock so long as (i) any adjustment required
by Section 5 is made and (ii) the Company shall have given notice thereof to the
Holder pursuant to Section 13;

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               (2) the issuance by the Company of Newly Issued Shares in an
offering for cash for the account of the Company that is underwritten on a firm
commitment basis and (A) is registered under the 1933 Act or (B) sold in an
offering to "qualified institutional buyers" as defined in, and in a transaction
under, Rule 144A under the 1933 Act;

               (3) the issuance by the Company of shares of Common Stock upon
conversion of the Notes in accordance with the Supplemental Indenture or upon
exercise of this Warrant or the Other Warrants in accordance with the terms
hereof and thereof;

               (4) the issuance by the Company of shares of Common Stock in
payment of interest on the Notes in accordance with the terms thereof and the
Supplemental Indenture;

               (5) the issuance by the Company of shares of Common Stock
pursuant to exercise of options, warrants or other rights outstanding as of the
first date of issuance of any of the Notes in accordance with their terms in
effect on the first date of issuance of any of the Notes; and

               (6) the issuance by the Company of shares of Common Stock
pursuant to the Common Stock Purchase Agreement.

               8. EFFECT OF RECLASSIFICATION, CONSOLIDATION, MERGER OR SALE. (a)
If any of the following events occur, namely (i) any reclassification or change
of the outstanding shares of Common Stock (other than a change in par value, or
from par value to no par value, or from no par value to par value, or as a
result of a subdivision or combination), (ii) any consolidation, merger or
combination of the Company with another corporation as a result of which holders
of Common Stock shall be entitled to receive stock, securities or other property
or assets (including cash) with respect to or in exchange for such Common Stock,
or (iii) any sale or conveyance of the properties and assets of the Company as,
or substantially as, an entirety to any other Person as a result of which
holders of Common Stock shall be entitled to receive stock, securities or other
property or assets (including cash) with respect to or in exchange for such
Common Stock, then the Company or the successor or purchasing Person, as the
case may be, shall execute with the Holder a written agreement providing that
(x) this Warrant shall thereafter entitle the Holder to purchase the kind and
amount of shares of stock and Other Securities or property or assets (including
cash) receivable upon such reclassification, change, consolidation, merger,
combination, sale or conveyance by the holder of a number of shares of Common
Stock issuable upon exercise of this Warrant (assuming, for such purposes, a
sufficient number of authorized shares of Common Stock available to exercise
this Warrant) immediately prior to such reclassification, change, consolidation,
merger, combination, sale or conveyance assuming such holder of

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Common Stock did not exercise such holder's rights of election, if any, as to
the kind or amount of securities, cash or other property receivable upon such
consolidation, merger, statutory exchange, sale or conveyance (provided that, if
the kind or amount of securities, cash or other property receivable upon such
consolidation, merger, statutory exchange, sale or conveyance is not the same
for each share of Common Stock in respect of which such rights of election shall
not have been exercised ("non-electing share"), then for the purposes of this
Section 8 the kind and amount of securities, cash or other property receivable
upon such consolidation, merger, statutory exchange, sale or conveyance for each
non-electing share shall be deemed to be the kind and amount so receivable per
share by a plurality of the non-electing shares), (y) in the case of any such
successor or purchasing Person, upon such consolidation, merger, combination,
sale or conveyance such successor or purchasing Person shall be jointly and
severally liable with the Company for the performance of all of the Company's
obligations under this Warrant and this Note Purchase Agreement and (z) if
registration or qualification is required under the 1933 Act or applicable state
law for this Warrant or the issuance to the Holder of the shares of such shares
of stock and Other Securities so issuable upon exercise of this Warrant, such
registration or qualification shall be completed prior to such reclassification,
change, consolidation, merger, combination or sale. Such written agreement shall
provide for adjustments which shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Warrant. If, in the case of
any such reclassification, change, consolidation, merger, combination, sale or
conveyance, the stock or other securities and assets receivable thereupon by a
holder of shares of Common Stock includes shares of stock or other securities
and assets of a corporation other than the successor or purchasing corporation,
as the case may be, in such reclassification, change, consolidation, merger,
combination, sale or conveyance, then such written agreement shall also be
executed by such other corporation and shall contain such additional provisions
to protect the interests of the Holder as the Board of Directors shall
reasonably consider necessary by reason of the foregoing.

        (b) The above provisions of this Section 8 shall similarly apply to
successive reclassifications, changes, consolidations, mergers, combinations,
sales and conveyances.

        (c) If this Section 8 applies to any event or occurrence, Section 4
shall not apply to such event or occurrence.

        TAX ADJUSTMENTS. The Company may make such reductions in the Purchase
Price, in addition to those required by Sections 3, 4, 5, 6 and 7, as the Board
of Directors considers to be advisable to avoid or diminish any income tax to
holders of Common Stock or rights to purchase Common Stock resulting from any
dividend or distribution of stock (or rights to acquire stock) or from any event
treated as such for income tax purposes.

                                       13
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               10. MINIMUM ADJUSTMENT. (a) No adjustment in the Purchase Price
(and no related adjustment in the number of shares of Common Stock which may
thereafter be purchased upon exercise of this Warrant) shall be required unless
such adjustment would require an increase or decrease of at least 1% in the
Purchase Price; provided, however, that any adjustments which by reason of this
Section 10 are not required to be made shall be carried forward and taken into
account in any subsequent adjustment. All such calculations under this Warrant
shall be made by the Company and shall be made to the nearest cent or to the
nearest one hundredth of a share, as the case may be.

               (b) No adjustment need be made for a change in the par value of
the Common Stock or from par value to no par value or from no par value to par
value.

               11. NOTICE OF ADJUSTMENTS. Whenever the Purchase Price is
adjusted as herein provided, the Company shall promptly, but in no event later
than five Trading Days thereafter, give a notice to the Holder setting forth the
Purchase Price and number of shares of Common Stock which may be purchased upon
exercise of this Warrant after such adjustment and setting forth a brief
statement of the facts requiring such adjustment but which such statement shall
not include any information which would be material non-public information for
purposes of the 1934 Act. Failure to deliver such notice shall not affect the
legality or validity of any such adjustment.

               12. FURTHER ASSURANCES. The Company will take all action that may
be necessary or appropriate in order that the Company may validly and legally
issue fully paid and nonassessable shares of stock, free from all taxes, liens
and charges with respect to the issue thereof, on the exercise of all or any
portion of this Warrant from time to time outstanding.

               13. NOTICE TO HOLDER PRIOR TO CERTAIN ACTIONS. In case on or
after the Issuance Date:

               (a) the Company shall declare a dividend (or any other
distribution) on its Common Stock (other than in cash out of retained earnings);
or

               (b) the Company shall authorize the granting to the holders of
its Common Stock of rights or warrants to subscribe for or purchase any share of
any class or any other rights or warrants; or

               (c) the Board of Directors shall authorize any reclassification
of the Common Stock (other than a subdivision or combination of its outstanding
Common Stock, or a change in par value, or from par value to no par value, or
from no par value to par value), or any consolidation or merger or other
business combination

                                       14
   15


transaction to which the Company is a party and for which approval of any
stockholders of the Company is required, or the sale or transfer of all or
substantially all of the assets of the Company; or

               (d) there shall be pending the voluntary or involuntary
dissolution, liquidation or winding-up of the Company;

the Company shall give the Holder, as promptly as possible but in any event at
least ten Trading Days prior to the applicable date hereinafter specified, a
notice stating (x) the date on which a record is to be taken for the purpose of
such dividend, distribution or rights or warrants, or, if a record is not to be
taken, the date as of which the holders of Common Stock of record to be entitled
to such dividend, distribution or rights are to be determined, or (y) the date
on which such reclassification, consolidation, merger, other business
combination transaction, sale, transfer, dissolution, liquidation or winding-up
is expected to become effective or occur, and the date as of which it is
expected that holders of Common Stock of record who shall be entitled to
exchange their Common Stock for securities or other property deliverable upon
such reclassification, consolidation, merger, other business combination
transaction, sale, transfer, dissolution, liquidation or winding-up shall be
determined. Such notice shall not include any information which would be
material non-public information for purposes of the 1934 Act. Failure to give
such notice, or any defect therein, shall not affect the legality or validity of
such dividend, distribution, reclassification, consolidation, merger, sale,
transfer, dissolution, liquidation or winding-up. In the case of any such action
of which the Company gives such notice to the Holder or is required to give such
notice to the Holder, the Holder shall be entitled to give a subscription form
to exercise this Warrant in whole or in part that is contingent on the
completion of such action.

               14. RESERVATION OF STOCK, ETC., ISSUABLE ON EXERCISE OF WARRANTS.
The Company will at all times reserve and keep available out of its authorized
but unissued shares of capital stock, solely for issuance and delivery on the
exercise of this Warrant, a sufficient number of shares of Common Stock (or
Other Securities) to effect the full exercise of this Warrant and the exercise,
conversion or exchange of any other warrant or security of the Company
exercisable for, convertible into, exchangeable for or otherwise entitling the
holder to acquire shares of Common Stock (or Other Securities), and if at any
time the number of authorized but unissued shares of Common Stock (or Other
Securities) shall not be sufficient to effect such exercise, conversion or
exchange, the Company shall take such action as may be necessary to increase its
authorized but unissued shares of Common Stock (or Other Securities) to such
number as shall be sufficient for such purposes.

               15. TRANSFER OF WARRANT. This Warrant shall inure to the benefit
of the successors to and assigns of the Holder. This Warrant and all rights


                                       15
   16

hereunder, in whole or in part, are registrable at the office or agency of the
Company referred to below by the Holder in Person or by his duly authorized
attorney, upon surrender of this Warrant properly endorsed accompanied by an
assignment form in the form attached to this Warrant, or other customary form,
duly executed by the transferring Holder.

               16. REGISTER OF WARRANTS. The Company shall maintain, at the
principal office of the Company (or such other office as it may designate by
notice to the Holder), a register in which the Company shall record the name and
address of the Person in whose name this Warrant has been issued, as well as the
name and address of each successor and prior owner of such Warrant. The Company
shall be entitled to treat the Person in whose name this Warrant is so
registered as the sole and absolute owner of this Warrant for all purposes.

               17. EXCHANGE OF WARRANT. This Warrant is exchangeable, upon the
surrender hereof by the Holder at the office or agency of the Company referred
to in Section 15, for one or more new Warrants of like tenor representing in the
aggregate the right to subscribe for and purchase the number of shares of Common
Stock which may be subscribed for and purchased hereunder, each of such new
Warrants to represent the right to subscribe for and purchase such number of
shares as shall be designated by the Holder at the time of such surrender.

               18. REPLACEMENT OF WARRANT. On receipt by the Company of evidence
reasonably satisfactory to it of the ownership of and the loss, theft,
destruction or mutilation of this Warrant and (a) in the case of loss, theft or
destruction, of indemnity from the Holder reasonably satisfactory in form to the
Company (and without the requirement to post any bond or other security), or (b)
in the case of mutilation, upon surrender and cancellation of this Warrant, the
Company will execute and deliver to the Holder a new Warrant of like tenor
without charge to the Holder.

               19. WARRANT AGENT. The Company may, by written notice to the
Holder, appoint the transfer agent and registrar for the Common Stock as the
Company's agent for the purpose of issuing Common Stock (or Other Securities) on
the exercise of this Warrant pursuant to Section 1, and the Company may, by
written notice to the Holder, appoint an agent having an office in the United
States of America for the purpose of exchanging this Warrant pursuant to Section
17, and replacing this Warrant pursuant to Section 18, or any of the foregoing,
and thereafter any such exchange or replacement, as the case may be, shall be
made at such office by such agent.

               20. REMEDIES. The Company stipulates that the remedies at law of
the Holder in the event of any default or threatened default by the Company in
the performance of or compliance with any of the terms of this Warrant are not
and will

                                       16
   17

not be adequate, and that such terms may be specifically enforced by a decree
for the specific performance of any agreement contained herein or by an
injunction against a violation of any of the terms hereof or otherwise.

               21. NO RIGHTS OR LIABILITIES AS A STOCKHOLDER. This Warrant shall
not entitle the Holder to any voting rights or other rights as a stockholder of
the Company. Nothing contained in this Warrant shall be construed as conferring
upon Holder hereof the right to vote or to consent or to receive notice as a
stockholder of the Company on any matters or with respect to any rights
whatsoever as a stockholder of the Company. No dividends or interest shall be
payable or accrued in respect of this Warrant or the interest represented hereby
or the Common Stock (or Other Securities) purchasable hereunder until, and only
to the extent that, this Warrant shall have been exercised in accordance with
its terms.

               22. NOTICES, ETC. All notices and other communications from the
Company to the Holder shall be mailed by first class certified mail, postage
prepaid, at such address as may have been furnished to the Company in writing by
the Holder or at the address shown for the Holder on the register of Warrants
referred to in Section 16.

               23. AMENDMENT; WAIVER. This Warrant and any terms hereof may be
changed, waived, discharged or terminated only by an instrument in writing
signed by the party against which enforcement of such change, waiver, discharge
or termination is sought.

               24. MISCELLANEOUS. This Warrant shall be construed and enforced
in accordance with and governed by the internal laws of the State of New York.
The headings, captions and footers in this Warrant are for purposes of reference
only, and shall not limit or otherwise affect any of the terms hereof. The
invalidity or unenforceability of any provision hereof shall in no way affect
the validity or enforceability of any other provision.

               25. ATTORNEYS' FEES. In any litigation, arbitration or court
proceeding between the Company and Holder relating hereto, the prevailing party
shall be entitled to attorneys' fees and expenses and all costs of proceedings
incurred in enforcing this Warrant.

                                       17
   18


               IN WITNESS WHEREOF, the Company has caused this Warrant to be
duly executed on its behalf by one of its officers thereunto duly authorized.

Dated: September 22, 2000                AXYS PHARMACEUTICALS, INC.



                                         By:      /s/ William J. Newell
                                            -----------------------------------
                                             Name: William Newell
                                             Title: Senior Vice President

* The Company also executed a Class A Warrant with each of the following
  parties:

  Delta Opportunity Fund (Institutional), LLC
  Omicron Partners, L.P.
  Otato Limited Partnership
  Gatx Ventures, Inc.
  Alexander Enterprise Holdings, Corp.
  Cumberland Partners
  Cumber International S.A.
  Edwin L. Cox
  Longview Partners
  Charles V. Schaefer Jr.
  Longview Partners B, L.P.
  Delta Associates Limited Partnership
  Longview Partners C, L.P.
  Cumberland Benchmarked Partners, L.P.
  Longview Partners A, L.P.

                                       18
   19


                                   ASSIGNMENT

               For value received _________________________ hereby sell(s),
assign(s) and transfer(s) unto _________________________ (Please insert social
security or other Taxpayer Identification Number of assignee:
______________________________) the attached original, executed Warrant to
purchase _____ share of Common Stock of Axys Pharmaceuticals, Inc., a Delaware
corporation, and hereby irrevocably constitutes and appoints
_________________________ attorney to transfer the Warrant on the books of the
Company, with full power of substitution in the premises.

               Capitalized terms used in this Assignment and not defined in this
Assignment shall have the respective meanings provided in the Warrant.



Dated:                                         NAME:
      ---------------------------------             ----------------------------



                                                    ----------------------------
                                                            Signature(s)




   20


                                                                       EXHIBIT 1

                              FORM OF SUBSCRIPTION

                           AXYS PHARMACEUTICALS, INC.

                          (To be signed only on exercise of Warrant)

TO:     Axys Pharmaceuticals, Inc.
        180 Kimball Way
        South San Francisco, California 94080

        Attention:  Chief Financial Officer

        Facsimile No.: (650) 829-1067

        1. The undersigned Holder of the attached original, executed Warrant
hereby elects to exercise its purchase right under such Warrant with respect to
______________ shares (the "Exercise Shares") of Common Stock, as defined in the
Warrant, of Axys Pharmaceuticals, Inc., a Delaware corporation (the "Company").

        2.     The undersigned Holder (check one):

        [ ]    (a) elects to pay the Aggregate Purchase Price for such shares of
               Common Stock (i) in lawful money of the United States or by the
               enclosed certified or official bank check payable in United
               States dollars to the order of the Company in the amount of
               $___________, or (ii) by wire transfer of United States funds to
               the account of the Company in the amount of $____________, which
               transfer has been made before or simultaneously with the delivery
               of this Form of Subscription pursuant to the instructions of the
               Company;

               or

        [ ]    (b) elects to receive shares of Common Stock having a value equal
               to the value of the Warrant calculated in accordance with Section
               1(b) of the Warrant.

        3. Please issue a stock certificate or certificates representing the
appropriate number of shares of Common Stock in the name of the undersigned or
in such other name(s) as is specified below:

        Name:
             ----------------------------------


   21




        Address:
                ------------------------------------------

        Social Security or Tax Identification Number (if any):




Dated:
                                ------------------------------------------------
                                (Signature must conform to name of Holder as
                                specified on the face of the Warrant)


                                ------------------------------------------------

                                ------------------------------------------------



(Address)