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                                                                     EXHIBIT 4.4

                      INCARA PHARMACEUTICALS CORPORATION

                                    WARRANT
                                    -------

Warrant No. CO-_____                                    Dated: ___________, 2001


     Incara Pharmaceuticals Corporation, a Delaware corporationa (the
"Company"), hereby certifies that, for value received, [    ] or its registered
 -------
assigns ("Holder"), is entitled, subject to the terms set forth below, to
          ------
purchase from the Company up to a total of ___________ shares of common stock,
$0.001 par value per share (the "Common Stock"), of the Company (each such
                                 ------------
share, a "Warrant Share" and all such shares, the "Warrant Shares") at an
          -------------                            --------------
exercise price equal to $_________ per share (as adjusted from time to time as
provided in Section 7, the "Exercise Price"), at any time and from time to time
from and after the date hereof and through and including ___________, 2006 (the
"Expiration Date"), and subject to the following terms and conditions.
 ---------------

          1.  Registration of Warrant.  The Company shall register this Warrant,
              -----------------------
upon records to be maintained by the Company for that purpose (the "Warrant
                                                                    -------
Register"), in the name of the record Holder hereof from time to time.  The
--------
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes, and the Company shall not be affected by
notice to the contrary.

          2.   Registration of Transfers and Exchanges.
               ---------------------------------------

          (a) Subject to compliance with applicable securities laws, the Company
shall register the transfer of any portion of this Warrant in the Warrant
Register, upon surrender of this Warrant, with the Form of Assignment attached
hereto duly completed and signed, to the Transfer Agent or to the Company at its
address for notice set forth in Section 10.  Upon any such registration or
transfer, a new warrant to purchase Common Stock, in substantially the form of
this Warrant (any such new warrant, a "New Warrant"), evidencing the portion of
                                       -----------
this Warrant so transferred shall be issued to the transferee and a New Warrant
evidencing the remaining portion of this Warrant not so transferred, if any,
shall be issued to the transferring Holder.  The acceptance of the New Warrant
by the transferee thereof shall be deemed the acceptance of such transferee of
all of the rights and obligations of a holder of a Warrant.

          (b) This Warrant is exchangeable, upon the surrender hereof by the
Holder to the office of the Company at its address for notice set forth in
Section 10, for one or more New Warrants, evidencing in the aggregate the right
to purchase the number of Warrant Shares which may then be purchased hereunder.
Any such New Warrant will be dated the date of such exchange.
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          3.  Duration and Exercise of Warrants.
              ---------------------------------

          (a) This Warrant shall be exercisable by the registered Holder on any
business day before 5:00 P.M., New York City time, at any time and from time to
time on or after the date hereof to and including the Expiration Date.  At 5:00
P.M., New York City time on the Expiration Date, the portion of this Warrant not
exercised prior thereto shall be and become void and of no value.

          (b) Upon surrender of this Warrant, with the Form of Election to
Purchase attached hereto duly completed and signed, to the Company at its
address for notice set forth in Section 10  and upon payment of the Exercise
Price multiplied by the number of Warrant Shares that the Holder intends to
purchase hereunder, in the manner provided hereunder, all as specified by the
Holder in the Form of Election to Purchase, the Company shall promptly (but in
no event later than five (5) business days after the Date of Exercise (as
defined herein)) issue or cause to be issued and cause to be delivered to or
upon the written order of the Holder and in such name or names as the Holder may
designate, a certificate for the Warrant Shares issuable upon such exercise,
free of restrictive legends except as required by applicable law. Any person so
designated by the Holder to receive Warrant Shares shall be deemed to have
become holder of record of such Warrant Shares as of the Date of Exercise of
this Warrant.  The Company shall, upon request of the Holder, if available, use
its best efforts to deliver Warrant Shares hereunder electronically through the
Depository Trust Corporation or another established clearing corporation
performing similar functions.

          A "Date of Exercise" means the date on which the Company shall have
             ----------------
received (i) this Warrant (or any New Warrant, as applicable), with the Form of
Election to Purchase attached hereto (or attached to such New Warrant)
appropriately completed and duly signed, and (ii) payment of the Exercise Price
for the number of Warrant Shares so indicated by the holder hereof to be
purchased.

          (c) This Warrant shall not be exercisable to the extent that the
shares of Common Stock issuable upon any exercise of hereof, when aggregated
with all other shares of Common Stock then owned by the Holder (as defined in
the Purchase Agreement), would result in the Holder owning more than 4.99% of
all of such Common Stock as would be outstanding on such date of exercise, as
determined in accordance with Rule 13d-3 under the Securities Exchange Act of
1934.

          4.  Payment of Taxes.  The Company will pay all documentary stamp
              ----------------
taxes attributable to the issuance of Warrant Shares upon the exercise of this
Warrant; provided, however, that the Company shall not be required to pay any
tax which may be payable in respect of any transfer involved in the registration
of any certificates for Warrant Shares or Warrants in a name other than that of
the Holder.  The Holder shall be responsible for all other tax liability that
may arise as a result of holding or transferring this Warrant or receiving
Warrant Shares upon exercise hereof.

                                       2
<PAGE>

          5.  Replacement of Warrant.  If this Warrant is mutilated, lost,
              ----------------------
stolen or destroyed, the Company shall issue or cause to be issued in exchange
and substitution for and upon cancellation hereof, or in lieu of and
substitution for this Warrant, a New Warrant, but only upon receipt of evidence
reasonably satisfactory to the Company of such loss, theft or destruction and
indemnity, if requested, satisfactory to it.  Applicants for a New Warrant under
such circumstances shall also comply with such other reasonable regulations and
procedures and pay such other reasonable charges as the Company may prescribe.

          6.  Reservation of Warrant Shares.  The Company covenants that it will
              -----------------------------
at all times reserve and keep available out of the aggregate of its authorized
but unissued Common Stock, solely for the purpose of enabling it to issue
Warrant Shares upon exercise of this Warrant as herein provided, the number of
Warrant Shares which are then issuable and deliverable upon the exercise of this
entire Warrant, free from preemptive rights or any other actual contingent
purchase rights of persons other than the Holder (taking into account the
adjustments and restrictions of Section 7). The Company covenants that all
Warrant Shares that shall be so issuable and deliverable shall, upon issuance
and the payment of the applicable Exercise Price in accordance with the terms
hereof, be duly and validly authorized, issued and fully paid and nonassessable.

          7.  Certain Adjustments.  The Exercise Price and number of Warrant
              -------------------
Shares issuable upon exercise of this Warrant are subject to adjustment from
time to time as set forth in this Section 7.  Upon each such adjustment of the
Exercise Price pursuant to this Section 7, the Holder shall thereafter prior to
the Expiration Date be entitled to purchase, at the Exercise Price resulting
from such adjustment, the number of Warrant Shares obtained by multiplying the
Exercise Price in effect immediately prior to such adjustment by the number of
Warrant Shares issuable upon exercise of this Warrant immediately prior to such
adjustment and dividing the product thereof by the Exercise Price resulting from
such adjustment.

          (a) If the Company, at any time while this Warrant is outstanding, (i)
shall pay a stock dividend or otherwise make a distribution or distributions on
shares of its Common Stock or on any other class of capital stock payable in
shares of Common Stock, (ii) subdivide outstanding shares of Common Stock into a
larger number of shares, or (iii) combine outstanding shares of Common Stock
into a smaller number of shares, then the Exercise Price shall be multiplied by
a fraction of which the numerator shall be the number of shares of Common Stock
(excluding treasury shares, if any) outstanding before such event and of which
the denominator shall be the number of shares of Common Stock (excluding
treasury shares, if any) outstanding after such event. Any adjustment made
pursuant to this Section shall become effective immediately, and shall apply to
successive subdivisions and combinations.

          (b) In case of any reclassification of the Common Stock or any
compulsory share exchange pursuant to which the Common Stock is converted into
other securities, cash or property, then the Holder shall have the right
thereafter to exercise this Warrant only into the shares of stock and other
securities and property receivable upon or deemed to be held by holders of
Common Stock following such reclassification or share exchange, and the Holder
shall be entitled upon such event to receive such amount of securities or
property equal to the amount of Warrant Shares such Holder would have been
entitled to had such Holder exercised

                                       3
<PAGE>

this Warrant immediately prior to such reclassification or share exchange. The
terms of any such reclassification or share exchange shall include such terms so
as to continue to give to the Holder the right to receive the securities or
property set forth in this Section 7(b) upon any exercise following any such
reclassification or share exchange.

          (c) In case of any (1) merger or consolidation of the Company with or
into another Person where the Company is not the surviving entity, or (2) sale
by the Company of all or substantially all of the assets of the Company (on a
book value basis) in one or a series of related transactions, the Holder shall
have the right thereafter to (A) exercise this Warrant for the shares of stock
and other securities, cash and property receivable upon or deemed to be held by
holders of Common Stock following such merger, consolidation or sale, and the
Holder shall be entitled upon such event or series of related events to receive
such amount of securities, cash and property as the Common Stock for which this
Warrant could have been exercised immediately prior to such merger,
consolidation or sale would have been entitled or (B) in the case of a merger or
consolidation, (x) require the surviving entity to issue common stock purchase
warrants equal to the number Warrant Shares to which this Warrant then permits,
which newly issued warrant shall be identical  to this Warrant, and (y)
simultaneously with the issuance of such warrant, shall have the right to
exercise such warrant only into shares of stock and other securities, cash and
property receivable upon or deemed to be held by holders of Common Stock
following such merger or consolidation.   In the case of clause (B), the
exercise price for such new warrant shall be based upon the amount of
securities, cash and property that each share of Common Stock would receive in
such transaction and the Exercise Price of this Warrant immediately prior to the
effectiveness or closing date for such transaction. The terms of any such
merger, sale or consolidation shall include such terms so as continue to give
the Holder the right to receive the securities, cash and property set forth in
this Section upon any conversion or redemption following such event. This
provision shall similarly apply to successive such events.

          (d) For the purposes of this Section 7, the following clauses
shall also be applicable:

                   (i)  Record Date.  In case the Company shall take a record
                        -----------
of the holders of its Common Stock for the purpose of entitling them (A) to
receive a dividend or other

                                       4
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distribution payable in Common Stock or in securities convertible or
exchangeable into shares of Common Stock, or (B) to subscribe for or purchase
Common Stock or securities convertible or exchangeable into shares of Common
Stock, then such record date shall be deemed to be the date of the issue or sale
of the shares of Common Stock deemed to have been issued or sold upon the
declaration of such dividend or the making of such other distribution or the
date of the granting of such right of subscription or purchase, as the case may
be.

                   (ii)  Treasury Shares.  The number of shares of Common Stock
                         ---------------
outstanding at any given time shall not include shares owned or held by or for
the account of the Company, and the disposition of any such shares shall be
considered an issue or sale of Common Stock.

          (e) All calculations under this Section 7 shall be made to the nearest
cent or the nearest whole share, as the case may be.

          (f)  If:

               (i)    the Company shall declare a dividend (or any other
     distribution) on its Common Stock; or

               (ii)   the Company shall declare a special nonrecurring cash
     dividend on or a redemption of its Common Stock; or

               (iii)  the Company shall authorize the granting to all holders of
     the Common Stock rights or warrants to subscribe for or purchase any shares
     of capital stock of any class or of any rights; or

               (iv)   the approval of any stockholders of the Company shall be
     required in connection with any reclassification of the Common Stock, any
     consolidation or merger to which the Company is a party, any sale or
     transfer of all or substantially all of the assets of the Company, or any
     compulsory share exchange whereby the Common Stock is converted into other
     securities, cash or property; or

               (v)   the Company shall authorize the voluntary dissolution,
     liquidation or winding up of the affairs of the Company,

                                       5
<PAGE>

then the Company shall cause to be mailed to each Holder at their last addresses
as they shall appear upon the Warrant Register, at least 10 calendar days prior
to the applicable record or effective date hereinafter specified, a notice
stating (x) the date on which a record is to be taken for the purpose of such
dividend, distribution, redemption, 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, distributions, redemption, rights or warrants are to
be determined or (y) the date on which such reclassification, consolidation,
merger, sale, transfer or share exchange is expected to become effective or
close, and the date as of which it is expected that holders of Common Stock of
record shall be entitled to exchange their shares of Common Stock for
securities, cash or other property deliverable upon such reclassification,
consolidation, merger, sale, transfer, share exchange, dissolution, liquidation
or winding up; provided, however, that the failure to mail such notice or any
               --------  -------
defect therein or in the mailing thereof shall not affect the validity of the
corporate action required to be specified in such notice.

          8.  Payment of Exercise Price.  The Holder shall pay the Exercise
              -------------------------
Price by delivery of immediately available funds.

          9.  Fractional Shares.  The Company shall not be required to issue or
              -----------------
cause to be issued fractional Warrant Shares on the exercise of this Warrant.
The number of full Warrant Shares which shall be issuable upon the exercise of
this Warrant shall be computed on the basis of the aggregate number of Warrant
Shares purchasable on exercise of this Warrant so presented.  If any fraction of
a Warrant Share would, except for the provisions of this Section, be issuable on
the exercise of this Warrant, the Company shall pay an amount in cash equal to
the Exercise Price multiplied by such fraction.

                                       6
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          10.  Notices.  Any and all notices or other communications or
               -------
deliveries hereunder shall be in writing and shall be deemed given and effective
on the earliest of (i) the date of transmission, if such notice or communication
is delivered via facsimile at the facsimile telephone number specified in this
Section prior to 5:00 p.m. (New York City time) on a business day, (ii) the
business day after the date of transmission, if such notice or communication is
delivered via facsimile at the facsimile telephone number specified in this
Section later than 5:00 p.m. (New York City time) on any date and earlier than
11:59 p.m. (New York City time) on such date, (iii) the business day following
the date of mailing, if sent by nationally recognized overnight courier service,
or (iv) upon actual receipt by the party to whom such notice is required to be
given.  The addresses for such communications shall be:  (i) if to the Company,
to 79 T.W. Alexander Drive, 4401 Research Commons, Suite 200,  P.O. Box 14287,
Research Triangle Park, North Carolina 27709, or (ii) if to the Holder, to the
Holder at the address or facsimile number appearing on the Warrant Register or
such other address or facsimile number as the Holder may provide to the Company
in accordance with this Section.

          11.  Warrant Agent.  The Company shall serve as warrant agent under
               -------------
this Warrant.  Upon thirty (30) days' notice to the Holder, the Company may
appoint a new warrant agent.  Any corporation into which the Company or any new
warrant agent may be merged or any corporation resulting from any consolidation
to which the Company or any new warrant agent shall be a party or any
corporation to which the Company or any new warrant agent transfers
substantially all of its corporate trust or shareholders services business shall
be a successor warrant agent under this Warrant without any further act.  Any
such successor warrant agent shall promptly cause notice of its succession as
warrant agent to be mailed (by first class mail, postage prepaid) to the Holder
at the Holder's last address as shown on the Warrant Register.

          12.  Optional Redemption.
               --------------------

               (a) This Warrant may be redeemed in whole during the
Effectiveness Period at the option of the Company, upon 30 days written notice
to the Holder, at a price equal to $0.01 per Warrant Share (the "Redemption
Price") if, and only if, at the time notice of such redemption is given by the
        ---------------
Company to the Holder as provided in Section 10 hereof, the Closing Price for
the Common Stock for each of the thirty (30) consecutive trading days
immediately preceding the date that the redemption notice is given exceeds
[$____] [3 X Exercise Price]. For the purpose of the foregoing sentence, the
term "Closing Price" shall mean, for any relevant day, the last sale price on
that day as reported by the principal exchange or quotation system on which
prices for the Common Stock are reported. On the redemption date the holders of
record of redeemed Warrants shall be entitled to payment of the Redemption Price
upon surrender of such redeemed Warrants to the Warrant Agent at the principal
office of the Warrant Agent.

               (b) From and after the redemption date, all rights of the Holder
(except the right to receive the Redemption Price) shall terminate, but only if
(i) on or before the redemption date the Company shall have irrevocably
deposited with the Warrant Agent as paying agent a sufficient amount to pay on
the redemption date the Redemption Price for all Warrants called for

                                       7
<PAGE>

redemption, and (ii) the notice of redemption shall have stated the name and
address of the Warrant Agent and the intention of the Company to deposit such
amount with the Warrant Agent no later than one day prior to the redemption
date.

          (c) If the Company fails to make a sufficient deposit with the Warrant
Agent as provided above, the holder of any Warrants called for redemption may at
the option of the Holder (a) by notice to the Company declare the notice of
redemption a nullity as to such holder, or (b) maintain an action against the
Company for the Redemption Price.  If the Holder brings such an action, the
Company will pay reasonable attorneys' fees of the Holder.  If the Holder fails
to bring an action against the Company for the Redemption Price within 60 days
after the redemption date, the Holder shall be deemed to have elected to declare
the notice of redemption to be a nullity and such notice shall be without any
force or effect.  Except as otherwise specifically provided in this provision, a
notice of redemption, once mailed by the Company as provided herein, shall be
irrevocable.

     13.  Miscellaneous.
          -------------

          (a) This Warrant shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns.  This Warrant may be
amended only in writing signed by the Company and the Holder and their
successors and assigns.

          (b) Subject to Section 13(a), above, nothing in this Warrant shall be
construed to give to any person or corporation other than the Company and the
Holder any legal or equitable right, remedy or cause under this Warrant.  This
Warrant shall inure to the sole and exclusive benefit of the Company and the
Holder.

          (c) The corporate laws of the State of Delaware shall govern all
issues concerning the relative rights of the Company and its stockholders.  All
other questions concerning the construction, validity, enforcement and
interpretation of this Warrant shall be governed by and construed and enforced
in accordance with the internal laws of the State of Delaware , without regard
to the principles of conflicts of law thereof.  The Company and the Holder
hereby irrevocably submit to the exclusive jurisdiction of the state and federal
courts sitting in the City of Wilmington, Delaware, for the adjudication of any
dispute hereunder or in connection herewith or with any transaction contemplated
hereby or discussed herein, and hereby irrevocably waives, and agrees not to
assert in any suit, action or proceeding, any claim that it is not personally
subject to the jurisdiction of any such court, or that such suit, action or
proceeding is improper.  Each of the Company and the Holder hereby irrevocably
waives personal service of process and consents to process being served in any
such suit, action or proceeding by receiving a copy thereof sent to the Company
at the address in effect for notices to it under this instrument and agrees that
such service shall constitute good and sufficient service of process and notice
thereof.  Nothing contained herein shall be deemed to limit in any way any right
to serve process in any manner permitted by law.

          (d) The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

                                       8
<PAGE>

          (e) In case any one or more of the provisions of this Warrant shall be
invalid or unenforceable in any respect, the validity and enforceability of the
remaining terms and provisions of this Warrant shall not in any way be affected
or impaired thereby and the parties will attempt in good faith to agree upon a
valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.



                           [SIGNATURE PAGE FOLLOWS]

                                       9
<PAGE>

     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
by its authorized officer as of the date first indicated above.




                        INCARA PHARMACEUTICALS CORPORATION

                         By:  _____________________________________________
                              Name:   Clayton I. Duncan
                              Title:  President and Chief Executive Officer
<PAGE>

                         FORM OF ELECTION TO PURCHASE

(To be executed by the Holder to exercise the right to purchase shares of Common
Stock under the foregoing Warrant)

To _________________:

     In accordance with the Warrant enclosed with this Form of Election to
Purchase, the undersigned hereby irrevocably elects to purchase  _____________
shares of common stock,  $0.001 par value per share, of Incara Pharmaceuticals
Corporation (the "Common Stock") and encloses herewith $________ in cash,
certified or official bank check or checks, which sum represents the aggregate
Exercise Price (as defined in the Warrant) for the number of shares of Common
Stock to which this Form of Election to Purchase relates, together with any
applicable taxes payable by the undersigned pursuant to the Warrant.

     The undersigned requests that certificates for the shares of Common Stock
issuable upon this exercise be issued in the name of

                                    PLEASE INSERT SOCIAL SECURITY OR
                                    TAX IDENTIFICATION NUMBER


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


 ----------------------------------------------------------------------------
                        (Please print name and address)



     If the number of shares of Common Stock issuable upon this exercise shall
not be all of the shares of Common Stock which the undersigned is entitled to
purchase in accordance with the enclosed Warrant, the undersigned requests that
a New Warrant (as defined in the Warrant) evidencing the right to purchase the
shares of Common Stock not issuable pursuant to the exercise evidenced hereby be
issued in the name of and delivered to:


 -----------------------------------------------------------------------------
                        (Please print name and address)





Dated:      ,                        Name of Holder:
      -----  --------------


                                    (Print)
                                            ----------------------------------
                                    (By:)
                                            ----------------------------------
                                    (Name:)
                                    (Title:)
                                    (Signature must conform in all respects to
                                    name of holder as specified on the face of
                                    the Warrant)
<PAGE>

                              FORM OF ASSIGNMENT

          [To be completed and signed only upon transfer of Warrant]

     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto ________________________________ the right represented by the within
Warrant to purchase  ____________ shares of Common Stock of Incara
Pharmaceuticals Corporation to which the within Warrant relates and appoints
________________ attorney to transfer said right on the books of Incara
Pharmaceuticals Corporation with full power of substitution in the premises.

Dated:

_______________, _________


                         __________________________________________________
                         (Signature must conform in all respects to name of
                         holder as specified on the face of the Warrant)


                         _______________________________________
                         Address of Transferee

                         _______________________________________

                         _______________________________________



In the presence of:


__________________________