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                                                                     EXHIBIT 3.1

                      RESTATED CERTIFICATE OF INCORPORATION
                            OF COR THERAPEUTICS, INC.
                                 * * * * * * * *

        Pursuant to Sections 242 and 245 of the General Corporation Law of
Delaware:

                VAUGHN M. KAILIAN and R. LEE DOUGLAS, JR. each hereby certifies
that:

                1. They are the President and Chief Executive Officer and
Secretary, respectively, of COR THERAPEUTICS, INC., a Delaware corporation, the
original Certificate of Incorporation of which was filed with the Secretary of
State of the State of Delaware on February 4, 1988 under this name.

                2. The certificate of incorporation of this corporation is
amended and restated to read as follows:

        FIRST. The name of the corporation is COR Therapeutics, Inc.

        SECOND. The address of its registered office in the State of Delaware is
15 East North Street, Dover, County of Kent, Delaware 19901. The name of its
registered agent at such address is Incorporating Services, Ltd.

        THIRD. The nature of the business or purposes to be conducted or
promoted is to engage in any lawful act or activity for which corporations may
be organized under the General Corporation Law of the State of Delaware.

        FOURTH. The total number of shares of all classes of capital stock which
the corporation shall have authority to issue is Twenty Five Million
(25,000,000) shares, comprised of Twenty Million (20,000,000) shares of Common
Stock $0.0001 par value (the "Common Stock") and Five Million (5,000,000) shares
of Preferred Stock $0.001 par value (the "Preferred Stock").

                The board of directors is expressly authorized, subject to the
limitations prescribed by law and the provisions of this Certificate of
Incorporation, to provide for the issuance of all or any shares of any wholly
unissued series of Preferred Stock, each with such designations, preferences,
voting powers (or no voting powers), relative, participating, optional or other
special rights and privileges and such qualifications, limitations or
restrictions thereof as shall be stated in the resolution or resolutions adopted
by the board of directors to create such series, and a certificate of
designations setting forth a copy of said resolution or resolutions shall be
filed in accordance with the General Corporation Law of the State of Delaware.
The authority



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of the board of directors with respect to each such series shall include without
limitation of the foregoing the right to specify the number of shares of each
such series and to authorize an increase or decrease in such number of shares
and the right to provide that the shares of each such series may be: (i) subject
to redemption at such time or times and at such price or prices; (ii) entitled
to receive dividends (which may be cumulative or non-cumulative) at such rates,
on such conditions, and at such times, and payable in preference to, or in such
relation to, the dividends payable on any other class or classes or any other
series; (iii) entitled to such rights upon the dissolution of, or upon any
distribution of the assets of, the corporation; (iv) convertible into, or
exchangeable for, shares of any other class or classes of stock, or of any other
series of the same or any other class or classes of stock of the corporation at
such price or prices or at such rates of exchange and with such adjustments, if
any; (v) entitled to the benefit of such limitations, if any, on the issuance of
additional shares of such series or shares of any other series of Preferred
Stock; or (vi) entitled to such other preferences, powers, qualifications,
rights and privileges, all as the board of directors may deem advisable and as
are not inconsistent with law and the provisions of this Certificate of
Incorporation. All preferences, voting powers, relative, participating, optional
or other special rights and privileges, and qualifications, limitations, or
restrictions of the Common Stock are expressly made subject and subordinate to
those that are fixed and those that may be fixed with respect to any shares of
the Preferred Stock.

        FIFTH. For the management of the business and for the conduct of the
affairs of the corporation, and in further definition, limitation and regulation
of the powers of the corporation, of its directors and of its stockholders or
any class thereof, as the case may be, it is further provided that:

                A. The board of directors of the corporation is expressly
authorized:

                        (i) To make, alter or repeal the by-laws of the
corporation.

                        (ii) To authorize and cause to be executed mortgages and
liens upon the real and personal property of the corporation.

                        (iii) To set apart out of any of the funds of the
corporation available for dividends a reserve or reserves for any proper purpose
and to abolish any such reserve in the manner in which it was created.

                        (iv) By a majority of the whole board, to designate one
or more committees, each committee to consist of one or more of the directors of
the corporation. The board may designate one or more directors as alternate
members of any committee, who may replace any absent or disqualified member of
any committee. The By-laws may provide that in the absence or disqualification
of a member of a committee, the member or members thereof present at any meeting
and not disqualified from voting, whether or not he or they constitute a quorum,
may unanimously appoint another member of the board of directors to act at the
meeting in the place of any such absent or disqualified member. Any such
committee, to the extent provided in the resolution of the board of directors,
or in the by-laws of the corporation, shall have and may exercise all the powers
and authority of the board of directors in the management of the business and
affairs of the corporation, and may authorize the seal of the corporation to be
affixed to all papers which may require it; but no such committee shall have the



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power or authority in reference to amending the Certificate of Incorporation
(except that a committee may, to the extent authorized in the resolution or
resolutions providing for the issuance of shares of stock adopted by the board
of directors as provided in Section 151(a) of the General Corporation Law of the
State of Delaware, fix any of the preferences or rights of such shares relating
to dividends, redemption, dissolution, any distribution of assets of the
corporation or the conversion into, or the exchange of such shares for, shares
of any other class or classes or any other series of the same or any other class
or classes of stock of the corporation), adopting an agreement of merger or
consolidation under Sections 251 or 252 of the General Corporation Law of the
State of Delaware, recommending to the stockholders the sale, lease or exchange,
of all or substantially all of the corporation's property and assets,
recommending to the stockholders a dissolution of the corporation or a
revocation of a dissolution, or amending the by-laws of the corporation; and,
unless the resolution or by-laws expressly so provide, no such committee shall
have the power or authority to declare a dividend, to authorize the issuance of
stock, or to adopt a certificate of ownership and merger pursuant to Section 253
of the General Corporation Law of the State of Delaware.

                B. Elections of directors need not be by written ballot unless
the by-laws of the corporation shall so provide.

                C. The books of the corporation may be kept at such place within
or without the State of Delaware as the by-laws of the corporation may provide
or as may be designated from time to time by the board of directors of the
corporation.

                D. The management of the business and the conduct of the affairs
of the corporation shall be vested in its Board of Directors.

                E. Any vacancies on the Board of Directors resulting from death,
resignation, disqualification, removal or other causes shall be filled by either
(i) the affirmative vote of the holders of a majority of the voting power of the
then-outstanding shares of voting stock of the corporation entitled to vote
generally in the election of directors (the "Voting Stock") voting together as a
single class; or (ii) by the affirmative vote of a majority of the remaining
directors then in office.

                F. The By-laws may be altered or amended or new Bylaws adopted
by the affirmative vote of a majority of the then-outstanding shares of the
Voting Stock. In furtherance and not in limitation of the power conferred by
statute, the Board of Directors is expressly authorized to adopt, amend,
supplement or repeal the By-laws.

        SIXTH. A. (1) Upon the closing of the Initial Public Offering, in
addition to any affirmative vote required by law, by this Certificate of
Incorporation or by any Preferred Stock Designation, and except as otherwise
expressly provided in Section B of this Article SIX:

                        (i) any merger or consolidation of the corporation or
any Subsidiary (as hereinafter defined) with (a) any Interested Stockholder (as
hereinafter defined) or (b) any other corporation (whether or not itself an
Interested Stockholder) which is, or after such merger or consolidation would
be, an Affiliate (as hereinafter defined) of an Interested Stockholder; or



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                        (ii) any sale, lease, exchange, mortgage, pledge,
transfer or other disposition (in one transaction or a series of transactions)
to or with any Interested Stockholder or any Affiliate of any Interested
Stockholder of any assets of the corporation or any Subsidiary having an
aggregate Fair Market Value (as hereinafter defined) equal to or greater than
15% of the Corporation's assets as set forth on the Corporation's most recent
audited consolidated financial statements; or

                        (iii) the issuance or transfer by the corporation or any
Subsidiary (in one transaction or a series of transactions) of any securities of
the corporation or any Subsidiary to any Interested Stockholder or any Affiliate
of any Interested Stockholder in exchange for cash, securities or other property
(or a combination thereof) having an aggregate Fair Market Value equal to or
greater than 15% of the Corporation's assets as set forth on the Corporation's
most recent audited consolidated financial statements; or

                        (iv) the adoption of any plan or proposal for the
liquidation or dissolution of the corporation proposed by or on behalf of any
Interested Stockholder or any Affiliate of any Interested Stockholder; or

                        (v) any reclassification of securities (including any
reverse stock split), or recapitalization of the corporation, or any merger or
consolidation of the corporation with any of its Subsidiaries or any other
transaction (whether or not with or into or otherwise involving any Interested
Stockholder) which has the effect, directly or indirectly, of increasing the
proportionate share of the outstanding shares of any class of equity or
convertible securities of the corporation or any Subsidiary which is
Beneficially Owned (as hereinafter defined) by any Interested Stockholder or any
Affiliate of any Interested Stockholder shall require the affirmative vote of
the holders of at least sixty-six and two-thirds percent (66-2/3%) of voting
power of all of the then-outstanding shares of the Voting Stock, voting together
as a single class. Such affirmative vote shall be required notwithstanding any
other provisions of this Certificate of Incorporation or any provision of law or
of any agreement with any national securities exchange or otherwise which might
otherwise permit a lesser vote or no vote.

                (2) The term "Business Combination" as used in this Article SIX
shall mean any transaction which is referred to in any one or more of
subparagraphs (i) through (v) of paragraph (1) of this Section A.

        B. The provisions of Section A of this Article SIX shall not be
applicable to any particular Business Combination, and such Business Combination
shall require only such affirmative vote as is required by law, any other
provision of this Certificate of Incorporation and any Preferred Stock
Designation, if, in the case of a Business Combination that does not involve any
cash or other consideration being received by the stockholders of the
corporation, solely in their respective capacities as stockholders of the
corporation, the condition specified in the following paragraph (1) is met, or,
in the case of any other Business Combination, the conditions specified in
either of the following paragraph (1) or paragraph (2) are met:

                (1) The Business Combination shall have been approved by:



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                        (i) a majority of the Continuing Directors (as
hereinafter defined); provided however, that this condition shall not be capable
of satisfaction unless there are at least two Continuing Directors; or (ii) a
majority of the shares not held by the Interested Stockholder.

                (2) All of the following conditions shall have been met:

                        (i) The consideration to be received by holders of
shares of a particular class (or series) of outstanding Voting Stock (including
Common Stock and other than Excluded Preferred Stock (as hereinafter defined))
shall be in cash or in the same form as the Interested Stockholder or any of its
Affiliates has previously paid for shares of such class (or series) of Voting
Stock. If the Interested Stockholder or any of its Affiliates have paid for
shares of any class (or series) of Voting Stock with varying forms of
consideration, the form of consideration to be received per share by holders of
shares of such class (or series) of Voting Stock shall be either cash or the
form used to acquire the largest number of shares of such class (or series) of
Voting Stock previously acquired by the Interested Stockholder.

                        (ii) The aggregate amount of (x) the cash and (y) the
Fair Market Value, as of the date (the "Consummation Date") of the consummation
of the Business Combination, of the consideration other than cash to be received
per share by holders of Common Stock in such Business Combination shall be at
least equal to the higher of the following (in each case appropriately adjusted
in the event of any stock dividend, stock split, combination of shares or
similar event):

                                (a) (if applicable) the highest per share price
                        paid by the Interested Stockholder or any of its
                        Affiliates for any shares of Common Stock acquired by
                        them within the two-year period immediately prior to the
                        date of the first public announcement of the proposal of
                        the Business Combination (the "Announcement Date") or in
                        any transaction in which the Interested Stockholder
                        became an Interested Stockholder, whichever is higher;
                        and

                                (b) the Fair Market Value per share of Common
                        Stock on the Announcement Date or the first date on
                        which the Interested Stockholder became an Interested
                        Stockholder (the "Determination Date") (which, if more
                        than two years prior to the Announcement Date shall be
                        deemed to be the date two years prior to the
                        Announcement Date), whichever is higher.

                        (iii) The aggregate amount of (x) the cash and (y) the
Fair Market Value, as of the Consummation Date, of the consideration other than
cash to be received per share by holders of shares of any class (or series),
other than Common Stock or Excluded Preferred Stock, of outstanding Voting Stock
shall be at least equal to the higher of the following (in each case
appropriately adjusted in the event of any stock dividend, stock split,
combination of shares or similar event), it being intended that the requirements
of this paragraph (2)(iii) shall be required to be met with respect to every
such class (or series) of outstanding Voting Stock



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whether or not the Interested Stockholder or any of its Affiliates has
previously acquired any shares of a particular class (or series) of Voting
Stock):

                                        (a) (if applicable) the highest per
                                share price paid by the Interested Stockholder
                                or any of its Affiliates for any shares of such
                                class (or series) of Voting Stock acquired by
                                them within the two-year period immediately
                                prior to the Announcement Date or in any
                                transaction in which it became an Interested
                                Stockholder, whichever is higher; and

                                        (b) the Fair Market Value per share of
                                such class (or series) of Voting Stock on the
                                Announcement Date or on the Determination Date,
                                whichever is higher.

                        (iv) After such Interested Stockholder has become an
Interested Stockholder and prior to the consummation of such Business
Combination: (a) except as approved by a majority of the Continuing Directors,
there shall have been no failure to declare and pay at the regular date therefor
any full quarterly dividends (whether or not cumulative) on any outstanding
Preferred Stock; (b) there shall have been (I) no reduction in the annual rate
of dividends paid on the Common Stock (except as necessary to reflect any
subdivision of the Common Stock), except as approved by a majority of the
Continuing Directors, and (II) an increase in such annual rate of dividends as
necessary to reflect any reclassification (including any reverse stock split),
recapitalization, reorganization or any similar transaction which has the effect
of reducing the number of outstanding shares of the Common Stock, unless the
failure so to increase such annual rate is approved by a majority of the
Continuing Directors; and (c) neither such Interested Stockholder nor any of its
Affiliates shall have become the beneficial owner of any additional shares of
Voting Stock except as part of the transaction which results in such Interested
Stockholder becoming an Interested Stockholder.

                        (v) After such Interested Stockholder has become an
Interested Stockholder, such Interested Stockholder and any of its Affiliates
shall not have received the benefit, directly or indirectly (except
proportionately, solely in such Interested Stockholder's or Affiliate's capacity
as a stockholder of the corporation), of any loans, advances, guarantees,
pledges or other financial assistance or any tax credits or other tax advantages
provided by the corporation, whether in anticipation of or in connection with
such Business Combination or otherwise.

                        (vi) A proxy or information statement describing the
proposed Business Combination and complying with the requirements of the
Securities Exchange Act of 1934, as amended, and the rules and regulations
thereunder (or any subsequent provisions replacing such Act, rules or
regulations) shall be mailed to all stockholders of the corporation at least 30
days prior to the consummation of such Business Combination (whether or not such
proxy or information statement is required to be mailed pursuant to such Act or
subsequent provisions).

                        (vii) Such Interested Stockholder shall have supplied
the corporation with such information as shall have been requested pursuant to
Section E of this Article SIX within the time period set forth therein.



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                C. For the purposes of this Article SIX:

                        (1) A "person" means any individual, limited
partnership, general partnership, corporation or other firm or entity.

                        (2) "Interested Stockholder" means any person (other
than the corporation or any Subsidiary) who or which:

                                (i) is the Beneficial Owner (as hereinafter
defined), directly or indirectly, of fifteen percent (15%) or more of the voting
power of all of the then-outstanding shares of the Voting Stock; or

                                (ii) if an Affiliate of the corporation and at
any time within the two-year period immediately prior to the date in question
was the Beneficial Owner, directly or indirectly, of fifteen percent (15%) or
more of the voting power of all of the then-outstanding shares of the Voting
Stock; or

                                (iii) is an assignee of or has otherwise
succeeded to any shares of Voting Stock which were at any time within the
two-year period immediately prior to the date in question beneficially owned by
an Interested Stockholder, if such assignment or succession shall have occurred
in the course of a transaction or series of transactions not involving a public
offering within the meaning of the 1933 Act.

                        (3) A person shall be a "Beneficial Owner" of, or shall
"Beneficially Own," any Voting Stock:

                                (i) which such person or any of its Affiliates
or Associates (as hereinafter defined) beneficially owns, directly or indirectly
within the meaning of Rule 13d-3 under the Securities Exchange Act of 1934, as
in effect on the adoption date of this Certificate of Incorporation; or

                                (ii) which such person or any of its Affiliates
or Associates has (a) the right to acquire (whether such right is exercisable
immediately or only after the passage of time), pursuant to any agreement,
arrangement or understanding or upon the exercise of conversion rights, exchange
rights, warrants or options, or otherwise, or (b) the right to vote pursuant to
any agreement, arrangement or understanding (but shall not be deemed to be the
Beneficial Owner of any shares of Voting Stock solely by reason of a revocable
proxy granted for a particular meeting of stockholders, pursuant to a public
solicitation of proxies for such meeting, and with respect to which shares
neither such person nor any such Affiliate or Associate is otherwise deemed the
Beneficial Owner); or

                                (iii) which is beneficially owned, directly or
indirectly, within the meaning of Rule 13d-3 under the Securities Exchange Act
of 1934, as in effect on the adoption date of this Certificate of Incorporation,
by any other person with which such person or any of its Affiliates or
Associates has any agreement, arrangement or understanding for the purpose of
acquiring, holding, voting (other than solely by reason of a revocable proxy as
described in subparagraph (ii) of this paragraph (3) or disposing of any shares
of Voting Stock; provided, however, that in case of any employee stock ownership
or similar plan of the



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corporation or of any Subsidiary in which the beneficiaries thereof possess the
right to vote any shares of Voting Stock held by such plan, no such plan nor any
trustee with respect thereto (nor any Affiliate of such trustee), solely by
reason of such capacity of such trustee, shall be deemed, for any purposes
hereof, to beneficially own any shares of Voting Stock held under any such plan.

                        (4) For the purposes of determining whether a person is
an Interested Stockholder pursuant to paragraph (2) of this Section C, the
number of shares of Voting Stock deemed to be outstanding shall include shares
deemed owned through application of paragraph (3) of this Section C but shall
not include any other unissued shares of Voting Stock which may be issuable
pursuant to any agreement, arrangement or understanding, or upon exercise of
conversion rights, warrants or options, or otherwise.

                        (5) "Affiliate" or "Associate" shall have the respective
meanings ascribed to such terms in Rule 12b-2 of the General Rules and
Regulations under the Securities Exchange Act of 1934, as in effect on the
adoption date of this Certificate of Incorporation.

                        (6) "Subsidiary" means any corporation of which a
majority of any class of equity security is owned, directly or indirectly, by
the corporation; provided, however, that for the purposes of the definition of
Interested Stockholder set forth in paragraph (2) of this Section C, the term
"Subsidiary" shall mean only a corporation of which a majority of each class of
equity security is owned directly or indirectly, by the corporation.

                        (7) "Continuing Director" means any member of the Board
of Directors of the corporation who is a director originally elected or
appointed upon incorporation of the corporation or who is not an Interested
Stockholder or affiliated with the Interested Stockholder and was a member of
the Board of Directors prior to the time that the Interested Stockholder became
an Interested Stockholder and any director who is thereafter chosen to fill any
vacancy on the Board of Directors or who is elected and who, in either event, is
not an Interested Stockholder or unaffiliated with the Interested Stockholder
and in connection with his or her initial assumption of office is recommended
for an appointment or election by a majority of Continuing Directors then on the
Board.

                        (8) "Fair Market Value" means: (i) in the case of stock,
the highest closing sale price on the last trading day immediately preceding the
date in question of a share of such stock on the Composite Tape for New York
Stock Exchange-Listed Stocks, or, if such stock is not quoted on the Composite
Tape, on the New York Stock Exchange, or, if such stock is not listed on such
Exchange, on the principal United States securities exchange registered under
the Securities Exchange Act of 1934 on which such stock is listed, or, if such
stock is not listed on any such exchange, the highest closing sale price
quotation with respect to a share of such stock on the last trading day
preceding the date in question on the National Association of Securities
Dealers, Inc. Automated Quotations System or any system then in use, or if no
such quotations are available, the fair market value on the date in question of
a share of such stock as deter-mined by the Board in accordance with Section D
of this Article SIX; and (ii) in the case of property other than cash or stock,
the fair market value of such property on the date in question as determined by
the Board in accordance with Section D of this Article SIX.



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                        (9) In the event of any Business Combination in which
the corporation survives, the phrase "consideration other than cash to be
received" as used in paragraphs (2)(ii) and (2)(iii) of Section B of this
Article SIX shall include the shares of Common Stock and/or the shares of any
other class (or series) of outstanding Voting Stock retained by the holders of
such shares.

                        (10) "Whole Board" means the total number of directors
which this corporation would have if there were no vacancies. (11) "Excluded
Preferred Stock" means any series of Preferred Stock with respect to which the
Preferred Stock Designation creating such series expressly provides that the
provisions of this Article SIX shall not apply.

                D. A majority of the Whole Board but only if a majority of the
Whole Board shall then consist of Continuing Directors or, if a majority of the
Whole Board shall not then consist of Continuing Directors, a majority of the
then Continuing Directors, shall have the power and duty to determine, on the
basis of information known to them after reasonable inquiry, all facts necessary
to determine compliance with this Article SIX, including, without limitation,
(i) whether a person is an Interested Stockholder, (ii) the number of shares of
Voting Stock beneficially owned by any person (iii) whether a person is an
Affiliate or Associate of another, (iv) whether the applicable conditions set
forth in paragraph (2) of Section B have been met with respect to any Business
Combination,(v) the Fair Market Value of stock or other property in accordance
with paragraph (8) of Section C of this Article SIX, and (vi) whether the assets
which are the subject of any Business Combination referred to in paragraph
(1)(ii) of Section A have or the consideration to be received for the issuance
or transfer of securities by the corporation or any Subsidiary in any Business
Combination referred to in paragraph (1)(iii) of Section A has, an aggregate
Fair Market Value equal to or greater than 15% of the Corporation's assets as
set forth on the Corporation's most recent audited consolidated financial
statements.

                E. A majority of the Whole Board shall have the right to demand,
but only if a majority of the Whole Board shall then consist of Continuing
Directors, or, if a majority of the Whole Board shall not then consist of
Continuing Directors, a majority of the then Continuing Directors shall have the
right to demand, that any person who it is reasonably believed is an Interested
Stockholder (or holds of record shares of Voting Stock Beneficially Owned by any
Interested Stockholder) supply this corporation with complete information as to
(i) the record owner(s) of all shares Beneficially Owned by such person who it
is reasonably believed is an Interested Stockholder, (ii) the number of, and
class or series of, shares Beneficially Owned by such person who it is
reasonably believed is an Interested Stockholder and held of record by each such
record owner and the number(s) of the stock certificate(s) evidencing such
shares, and (iii) any other factual matter relating to the applicability of
effect of this Article SIX, as may be reasonably requested of such person, and
such person shall furnish such information within 10 days after receipt of such
demand.

                F. Nothing contained in this Article SIX shall be construed to
relieve any Interested Stockholder from any fiduciary obligation imposed by law.



                                       9.
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        SEVENTH. The liability of the directors of the Corporation for monetary
damages shall be eliminated to the fullest extent permissible under Delaware
law.

        Any repeal or modification of the foregoing paragraph by the
stockholders of this corporation shall not adversely affect any right or
protection of a director of this corporation existing at the time of such repeal
or modification.

        EIGHTH.

                8.1 RIGHT TO INDEMNIFICATION. Each person who was or is made a
party or is threatened to be made a party to or is involved in any action, suit
or proceeding, whether civil, criminal, administrative or investigative
(hereinafter a "proceeding"), by reason of the fact that he or she, or a person
of whom he or she is the legal representative, is or was a director or officer
of the corporation or is or was serving at the request of the corporation as a
director or officer of another corporation or of a partnership, joint venture,
trust or other enterprise, including service with respect to employee benefit
plans, whether the basis of such proceeding is alleged action in an official
capacity as a director or officer or in any other capacity while serving as a
director or officer, shall be indemnified and held harmless by the corporation
to the fullest extent authorized by the Delaware General Corporation Law, as the
same exists or may hereafter be amended, (but, in the case of any such
amendment, only to the extent that such amendment permits the corporation to
provide broader indemnification rights than said law permitted the corporation
to provide prior to such amendment) against all expense, liability and loss
(including attorneys' fees, judgments, fines, ERISA excise taxes or penalties
and amounts paid to be paid in settlement) reasonably incurred or suffered by
such person in connection therewith and such indemnification shall continue as
to a person who has ceased to be a director or officer and shall inure to the
benefit of his or her heirs, executors and administrators; provided, however,
that except as provided in paragraph (b) hereof, the corporation shall indemnify
any such person seeking indemnification in connection with a proceeding (or part
thereof) initiated by such person only if such proceeding (or part thereof) was
authorized by the board of directors of the corporation. The right to
indemnification conferred in this Section shall be a contract right and shall
include the right to be paid by the corporation the expenses incurred in
defending any such proceeding in advance of its final disposition; provided,
however, that, if the Delaware General Corporation Law requires, the payment of
such expenses incurred by a director or officer in his or her capacity as a
director or officer (and not in any other capacity in which service was or is
rendered by such person while a director or officer, including, without
limitation, service to an employee benefit plan) in advance of the final
disposition of a proceeding, shall be made only upon delivery to the corporation
of an undertaking, by or on behalf of such director or officer, to repay all
amounts so advanced if it shall ultimately be determined that such director or
officer is not entitled to be indemnified under this Section or otherwise.

                8.2 RIGHT OF CLAIMANT TO BRING SUIT. If a claim under paragraph
8.1 is not paid in full by the corporation within ninety days after a written
claim has been received by the corporation, the claimant may at any time
thereafter bring suit against the corporation to recover the unpaid amount of
the claim and, if successful in whole or in part, the claimant shall be entitled
to be paid also the expense of prosecuting such claim. It shall be a defense to
any such action (other than an action brought to enforce a claim for expenses
incurred in defending any proceeding in advance of its final disposition where
the required undertaking, if any is required,



                                      10.
<PAGE>   11

has been tendered to the corporation) that the claimant has not met the
standards of conduct which make it permissible under the Delaware General
Corporation Law for the corporation to indemnify the claimant for the amount
claimed.

                8.3 NON-EXCLUSIVITY OF RIGHTS. The right to indemnification and
the payment of expenses incurred in defending a proceeding in advance of its
final disposition conferred in this Section shall not be exclusive of any other
right which any person may have or hereafter acquire under any statute,
provision of the Certificate of Incorporation, by-law, agreement, vote of
stockholders or disinterested directors or otherwise.

                8.4 INSURANCE. The corporation may maintain insurance, at its
expense, to protect itself and any director, officer, employee or agent of the
corporation or another corporation, partnership, joint venture, trust or other
enterprise against any such expense, liability or loss, whether or not the
corporation would have the power to indemnify such person against such expense,
liability or loss under the Delaware General Corporation Law.

        NINTH. The corporation is to have perpetual existence.

        TENTH. This corporation reserves the right to amend or repeal any
provision contained in this Restated Certificate of Incorporation, in the manner
now or hereafter prescribed by statute, and all rights conferred upon a
stockholder herein are granted subject to this reservation.

        3. In lieu of a meeting and vote of stockholders, the stockholders have
given written consent to the foregoing Restated Certificate of Incorporation in
accordance with the provisions of Section 228 of the General Corporation Law of
the State of Delaware, and written notice of the adoption of the Restated
Certificate of Incorporation has been given as provided in Section 228 of the
General Corporation Law of the State of Delaware to every stockholder entitled
to such notice.

        4. The aforementioned Restated Certificate of Incorporation was duly
adopted in accordance with the applicable provisions of the General Corporation
Law of the State of Delaware.



                                      11.
<PAGE>   12

        IN WITNESS WHEREOF, we have executed this Restated Certificate of
Incorporation on this 2nd day of July, 1991.

                                            /s/ Vaughn M. Kailian
                                            ----------------------------
                                            VAUGHN M. KAILIAN, President
                                            and Chief Executive Officer

Attest


/s/ R. Lee Douglas, Jr.
-----------------------
R. LEE DOUGLAS, JR.,
Secretary



                                      12.
<PAGE>   13

                           CERTIFICATE OF DESIGNATION

                                       OF

                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                       OF

                             COR THERAPEUTICS, INC.

                         (Pursuant to Section 151 of the
                        Delaware General Corporation Law)


        COR THERAPEUTICS, INC., a corporation organized and existing under the
General Corporation Law of the State of Delaware (hereinafter called the
"Corporation"), hereby certifies that the following resolution was adopted by
the Board of Directors of the Corporation as required by Section 151 of the
General Corporation Law in an action by written consent on January 23, 1995:

                RESOLVED, that pursuant to the authority granted to and vested
        in the Board of Directors of the Corporation in accordance with the
        provisions of its Restated Certificate of Incorporation, the Board of
        Directors hereby creates a series of Preferred Stock, par value $.001
        per share, of the Corporation and hereby states the designation and
        number of shares, and fixes the relative powers, preferences, rights,
        qualifications, limitations and restrictions thereof (in addition to the
        provisions set forth in the Restated Certificate of Incorporation of the
        Corporation, which are applicable to the Preferred Stock of all classes
        and series), as follows:

                Series A Junior Participating Preferred Stock:

                SECTION 1. DESIGNATION AND AMOUNT. Four Hundred Fifty Thousand
        (450,000) shares of Preferred Stock, $.001 par value, are designated
        "Series A Junior Participating Preferred Stock" with the powers,
        preferences, rights, qualifications, limitations and restrictions
        specified herein (the "Junior Preferred Stock"). Such number of shares
        may be increased or decreased by resolution of the Board of Directors;
        provided, that no decrease shall reduce the number of shares of Junior
        Preferred Stock to a number less than the number of shares then
        outstanding plus the number of shares reserved for issuance upon the
        exercise of outstanding options, rights or warrants or upon the
        conversion of any outstanding securities issued by the Corporation
        convertible into Junior Preferred Stock.



                                      13.
<PAGE>   14

                SECTION 2. DIVIDENDS AND DISTRIBUTIONS.

                (A) Subject to the rights of the holders of any shares of any
        series of Preferred Stock (or any similar stock) ranking prior and
        superior to the Junior Preferred Stock with respect to dividends, the
        holders of shares of Junior Preferred Stock, in preference to the
        holders of Common Stock, par value $.0001 per share (the "Common
        Stock"), of the Corporation, and of any other junior stock, shall be
        entitled to receive, when, as and if declared by the Board of Directors
        out of funds legally available for the purpose, quarterly dividends
        payable in cash on the first day of March, June, September and December
        in each year (each such date being referred to herein as a "Quarterly
        Dividend Payment Date"), commencing on the first Quarterly Dividend
        Payment Date after the first issuance of a share or fraction of a share
        of Junior Preferred Stock, in an amount per share (rounded to the
        nearest cent) equal to the greater of (a) $l.00 or (b) subject to the
        provision for adjustment hereinafter set forth, 100 times the aggregate
        per share amount of all cash dividends, and 100 times the aggregate per
        share amount (payable in kind) of all non-cash dividends or other
        distributions, other than a dividend payable in shares of Common Stock
        or a subdivision of the outstanding shares of Common Stock (by
        reclassification or otherwise) declared on the Common Stock since the
        immediately preceding Quarterly Dividend Payment Date or, with respect
        to the first Quarterly Dividend Payment Date, since the first issuance
        of any share or fraction of a share of Junior Preferred Stock. In the
        event the Corporation shall at any time declare or pay any dividend on
        the Common Stock payable in shares of Common Stock, or effect a
        subdivision or combination or consolidation of the outstanding shares of
        Common Stock (by reclassification or otherwise than by payment of a
        dividend in shares of Common Stock) into a greater or lesser number of
        shares of Common Stock, then in each such case the amount to which
        holders of shares of Junior Preferred Stock were entitled immediately
        prior to such event under clause (b) of the preceding sentence shall be
        adjusted by multiplying such amount by a fraction, the numerator of
        which is the number of shares of Common Stock outstanding immediately
        after such event and the denominator of which is the number of shares of
        Common Stock that were outstanding immediately prior to such event.

                (B) The Corporation shall declare a dividend or distribution on
        the Junior Preferred Stock as provided in paragraph (A) of this Section
        immediately after it declares a dividend or distribution on the Common
        Stock (other than a dividend payable in shares of Common Stock);
        provided that, in the event no dividend or distribution shall have been
        declared on the Common Stock during the period between any Quarterly
        Dividend Payment Date and the next subsequent Quarterly Dividend Payment
        Date, a dividend of $1.00 per share on the Junior Preferred Stock shall
        nevertheless be payable on such subsequent Quarterly Dividend Payment
        Date.

                (C) Dividends shall begin to accrue and be cumulative on
        outstanding shares of Junior Preferred Stock from the Quarterly Dividend
        Payment Date next preceding the date of issue of such shares, unless the
        date of issue of such shares is prior to the record date for the first
        Quarterly Dividend Payment Date, in which case dividends on such shares
        shall begin to accrue from the date of issue of such shares,



                                      14.
<PAGE>   15

        or unless the date of issue is a Quarterly Dividend Payment Date or is a
        date after the record date for the determination of holders of shares of
        Junior Preferred Stock entitled to receive a quarterly dividend and
        before such Quarterly Dividend Payment Date, in either of which events
        such dividends shall begin to accrue and be cumulative from such
        Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not
        bear interest. Dividends paid on the shares of Junior Preferred Stock in
        an amount less than the total amount of such dividends at the time
        accrued and payable on such shares shall be allocated pro rata on a
        share-by-share basis among all such shares at the time outstanding. The
        Board of Directors may fix a record date for the determination of
        holders of shares of Junior Preferred Stock entitled to receive payment
        of a dividend or distribution declared thereon, which record date shall
        be not more than 60 days prior to the date fixed for the payment
        thereof.

                SECTION 3. VOTING RIGHTS. The holders of shares of Junior
        Preferred Stock shall have the following voting rights:

                (A) Subject to the provision for adjustment hereinafter set
        forth, each share of Junior Preferred Stock shall entitle the holder
        thereof to 100 votes on all matters submitted to a vote of the
        stockholders of the Corporation. In the event the Corporation shall at
        any time declare or pay any dividend on the Common Stock payable in
        shares of Common Stock, or effect a subdivision or combination or
        consolidation of the outstanding shares of Common Stock (by
        reclassification or otherwise than by payment of a dividend in shares of
        Common Stock) into a greater or lesser number of shares of Common Stock,
        then in each such case the number of votes per share to which holders of
        shares of Junior Preferred Stock were entitled immediately prior to such
        event shall be adjusted by multiplying such number by a fraction, the
        numerator of which is the number of shares of Common Stock outstanding
        immediately after such event and the denominator of which is the number
        of shares of Common Stock that were outstanding immediately prior to
        such event.

                (B) Except as otherwise provided herein, in any other
        Certificate of Designation creating a series of Preferred Stock or any
        similar stock, or by law, the holders of shares of Junior Preferred
        Stock and the holders of shares of Common Stock and any other capital
        stock of the Corporation having general voting rights shall vote
        together as one class on all matters submitted to a vote of stockholders
        of the Corporation.

                (C) Except as set forth herein, or as otherwise provided by law,
        holders of Junior Preferred Stock shall have no special voting rights
        and their consent shall not be required (except to the extent they are
        entitled to vote with holders of Common Stock as set forth herein) for
        taking any corporate action.

                SECTION 4. CERTAIN RESTRICTIONS.



                                      15.
<PAGE>   16

                (A) Whenever quarterly dividends or other dividends or
        distributions payable on the Junior Preferred Stock as provided in
        Section 2 are in arrears, thereafter and until all accrued and unpaid
        dividends and distributions, whether or not declared, on shares of
        Junior Preferred Stock outstanding shall have been paid in full, the
        Corporation shall not:

                        (i) declare or pay dividends, or make any other
        distributions, on any shares of stock ranking junior (either as to
        dividends or upon liquidation, dissolution or winding up) to the Junior
        Preferred Stock;

                        (ii) declare or pay dividends, or make any other
        distributions, on any shares of stock ranking on a parity (either as to
        dividends or upon liquidation, dissolution or winding up) with the
        Junior Preferred Stock, except dividends paid ratably on the Junior
        Preferred Stock and all such parity stock on which dividends are payable
        or in arrears in proportion to the total amounts to which the holders of
        all such shares are then entitled;

                        (iii) redeem or purchase or otherwise acquire for
        consideration shares of any stock ranking junior (either as to dividends
        or upon liquidation, dissolution or winding up) to the Junior Preferred
        Stock, provided that the Corporation may at any time redeem, purchase or
        otherwise acquire shares of any such junior stock either (x) pursuant to
        any right of the Corporation to repurchase such junior stock issued
        pursuant to any compensatory contract or arrangement or (y) in exchange
        for shares of any stock of the Corporation ranking junior (either as to
        dividends or upon dissolution, liquidation or winding up) to the Junior
        Preferred Stock; or

                        (iv) redeem or purchase or otherwise acquire for
        consideration any shares of Junior Preferred Stock, or any shares of
        stock ranking on a parity with the Junior Preferred Stock, except in
        accordance with a purchase offer made in writing or by publication (as
        determined by the Board of Directors) to all holders of such shares upon
        such terms as the Board of Directors, after consideration of the
        respective annual dividend rates and other relative rights and
        preferences of the respective series and classes, shall determine in
        good faith will result in fair and equitable treatment among the
        respective series or classes.

                (B) The Corporation shall not permit any subsidiary of the
        Corporation to purchase or otherwise acquire for consideration any
        shares of stock of the Corporation unless the Corporation could, under
        paragraph (A) of this Section 4, purchase or otherwise acquire such
        shares at such time and in such manner.

                SECTION 5. REACQUIRED SHARES. Any shares of Junior Preferred
        Stock purchased or otherwise acquired by the Corporation in any manner
        whatsoever shall be retired and cancelled promptly after the acquisition
        thereof. All such shares shall upon their cancellation become authorized
        but unissued shares of Preferred Stock and may be reissued as part of a
        new series of Preferred Stock subject to the conditions and restrictions
        on issuance set forth herein, in the Restated Certificate of



                                      16.
<PAGE>   17

        Incorporation, or in any other Certificate of Designation creating a
        series of Preferred Stock or any similar stock or as otherwise required
        by law.

                SECTION 6. LIQUIDATION, DISSOLUTION OR WINDING UP. Upon any
        liquidation, dissolution or winding up of the Corporation, no
        distribution shall be made (1) to the holders of shares of stock ranking
        junior (either as to dividends or upon liquidation, dissolution or
        winding up) to the Junior Preferred Stock unless, prior thereto, the
        holders of shares of Junior Preferred Stock shall have received the
        greater of (i) $100 per share, plus an amount equal to accrued and
        unpaid dividends and distributions thereon, whether or not declared, to
        the date of such payment, or (ii) an aggregate amount per share, subject
        to the provision for adjustment hereinafter set forth, equal to 100
        times the aggregate amount to be distributed per share to holders of
        shares of Common Stock, or (2) to the holders of shares of stock ranking
        on a parity (either as to dividends or upon liquidation, dissolution or
        winding up) with the Junior Preferred Stock, except distributions made
        ratably on the Junior Preferred Stock and all such parity stock in
        proportion to the total amounts to which the holders of all such shares
        are entitled upon such liquidation, dissolution or winding up. In the
        event the Corporation shall at any time declare or pay any dividend on
        the Common Stock payable in shares of Common Stock, or effect a
        subdivision or combination or consolidation of the outstanding shares of
        Common Stock (by reclassification or otherwise than by payment of a
        dividend in shares of Common Stock) into a greater or lesser number of
        shares of Common Stock, then in each such case the aggregate amount to
        which holders of shares of Junior Preferred Stock were entitled
        immediately prior to such event under the proviso in clause (1) of the
        preceding sentence shall be adjusted by multiplying such amount by a
        fraction the numerator of which is the number of shares of Common Stock
        outstanding immediately after such event and the denominator of which is
        the number of shares of Common Stock that were outstanding immediately
        prior to such event.

                SECTION 7. CONSOLIDATION, MERGER, ETC. In case the Corporation
        shall enter into any consolidation, merger, combination or other
        transaction in which the shares of Common Stock are exchanged for or
        changed into other stock or securities, cash and/or any other property,
        then in any such case each share of Junior Preferred Stock shall at the
        same time be similarly exchanged or changed into an amount per share,
        subject to the provision for adjustment hereinafter set forth, equal to
        100 times the aggregate amount of stock, securities, cash and/or any
        other property (payable in kind), as the case may be, into which or for
        which each share of Common Stock is changed or exchanged. In the event
        the Corporation shall at any time declare or pay any dividend on the
        Common Stock payable in shares of Common Stock, or effect a subdivision
        or combination or consolidation of the outstanding shares of Common
        Stock (by reclassification or otherwise than by payment of a dividend in
        shares of Common Stock) into a greater or lesser number of shares of
        Common Stock, then in each such case the amount set forth in the
        preceding sentence with respect to the exchange or change of shares of
        Junior Preferred Stock shall be adjusted by multiplying such amount by a
        fraction, the numerator of which is the number of shares of Common Stock
        outstanding immediately after such event and the



                                      17.
<PAGE>   18

        denominator of which is the number of shares of Common Stock that were
        outstanding immediately prior to such event.

                SECTION 8. NO REDEMPTION. The shares of Junior Preferred Stock
        shall not be redeemable.

                SECTION 9. RANK. The Junior Preferred Stock shall rank, with
        respect to the payment of dividends and the distribution of assets,
        junior to all series of any other class of the Corporation's Preferred
        Stock.

                SECTION 10. AMENDMENT. The Restated Certificate of Incorporation
        of the Corporation shall not be amended in any manner which would
        materially alter or change the powers, preferences or special rights of
        the Junior Preferred Stock so as to affect them adversely without the
        affirmative vote of the holders of at least two-thirds of the
        outstanding shares of Junior Preferred Stock, voting together as a
        single class.

        IN WITNESS WHEREOF, the undersigned have executed this certificate as of
January 23, 1995.



                                           /s/ Vaughn M. Kailian
                                           ------------------------------------
                                           Vaughn M. Kailian
                                           President and Chief Executive Officer



                                           /s/ R. Lee Douglas, Jr.
                                           -------------------------------------
                                           R. Lee Douglas, Jr.
                                           Secretary



                                      18.
<PAGE>   19

                            CERTIFICATE OF AMENDMENT
                                       OF
                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                             COR THERAPEUTICS, INC.


        COR THERAPEUTICS, INC., a corporation organized and existing under and
by virtue of the General Corporation Law of the State of Delaware does hereby
certify that:

        FIRST: At a meeting of the Board of Directors of the corporation,
resolutions were duly adopted setting forth a proposed amendment of the Restated
Certificate of Incorporation of said corporation, declaring said amendment to be
advisable and calling a meeting of the stockholders of said corporation for
consideration thereof. The resolution setting forth the proposed amendment is as
follows:

        RESOLVED, that the Restated Certificate of Incorporation of this
corporation be amended by changing the Article thereof numbered "Fourth" so
that, as amended, said Article shall be and read in its entirety as follows:

        "FOURTH. The total number of shares of all classes of capital stock
which the corporation shall have authority to issue is One Hundred and
Twenty-Five Million (125,000,000) shares, comprised of One Hundred and Twenty
Million (120,000,000) shares of Common Stock, $0.0001 par value (the "Common
Stock"), and Five Million (5,000,000) shares of Preferred Stock, $0.001 par
value (the "Preferred Stock").

                The board of directors is expressly authorized, subject to the
        limitations prescribed by law and the provisions of the Restated
        Certificate of Incorporation, to provide for the issuance of all or any
        shares of any wholly unissued series of Preferred Stock, each with such
        designations, preferences, voting powers (or no voting powers),
        relative, participating, optional or other special rights and privileges
        and such qualifications, limitations or restrictions thereof as shall be
        stated in the resolution or resolutions adopted by the board of
        directors to create such series, and a certificate of designations
        setting forth a copy of said resolution or resolutions shall be filed in
        accordance with the General Corporation Law of the State of Delaware.
        The authority of the board of directors with respect to each such series
        shall include without limitation of the foregoing the right to specify
        the number of shares of each such series and to authorize an increase or
        decrease in such number of shares and the right to provide that the
        shares of each such series may be: (i) subject to redemption at such
        time or times and at such price or prices; (ii) entitled to receive
        dividends (which may be cumulative or non-cumulative) at such rates, on
        such conditions, and at such times, and payable in preference to, or in
        such relation to, the dividends payable on any other class or classes or
        any other series; (iii) entitled to such rights upon the dissolution of,
        or



                                      19.
<PAGE>   20

        upon any distribution of the assets of, the corporation; (iv)
        convertible into, or exchangeable for, shares of any other class or
        classes of stock, or of any other series of the same or any other class
        or classes of stock of the corporation at such price or prices or at
        such rates of exchange and with such adjustments, if any; (v) entitled
        to the benefit of such limitations, if any, on the issuance of
        additional shares of such series or shares of any other series of
        Preferred Stock; or (vi) entitled to such other preferences, powers,
        qualifications, rights and privileges, all as the board of directors may
        deem advisable and as are not inconsistent with law and the provisions
        of the Restated Certificate of Incorporation. All preferences, voting
        powers, relative, participating, optional or other special rights and
        privileges, and qualifications, limitation, or restrictions of the
        Common Stock are expressly made subject and subordinate to those that
        are fixed and those that may be fixed with respect to any shares of the
        Preferred Stock."


        SECOND: Thereafter, pursuant to resolution of its Board of Directors, a
meeting of the stockholders of said corporation was duly called and held, upon
notice in accordance with Section 222 of the General Corporation law of the
state of Delaware at which meeting the necessary number of shares as required by
statute were voted in favor of the amendment.

        THIRD: Said amendment was duly adopted in accordance with the provisions
of Section 242 of the General Corporation Law of the State of Delaware.

        IN WITNESS WHEREOF, said Corporation has caused this certificate to be
signed by Vaughn M. Kailian, its President, and Patrick A. Broderick, its
Secretary, this May day of 31, 2000.



                                            By:    /s/ Vaughn M. Kailian
                                            ------------------------------------
                                                       VAUGHN M. KAILIAN
                                                       PRESIDENT



                                            Attest:  /s/ Patrick A. Broderick
                                            ------------------------------------
                                                         PATRICK A. BRODERICK
                                                         SECRETARY



                                      20.