Document:

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                                                                   EXHIBIT 10.80

                              EMPLOYMENT AGREEMENT

     This Employment Agreement ("Agreement") is by and between Incara
Pharmaceuticals Corporation, a Delaware corporation having a place of business
at 79 T.W. Alexander Drive, 4401 Research Commons, Suite 200, Post Office Box
14287, Research Triangle Park, North Carolina, 27709 (the "Corporation"), and
Mark E. Furth, Ph.D. ("Employee").

                              W I T N E S S E T H:

     WHEREAS, the Corporation has employed and desires to continue to employ the
Employee as Senior Vice President, Research, and the Employee desires to be
employed by the Corporation as Senior Vice President, Research, all pursuant to
the terms and conditions hereinafter set forth;

     NOW, THEREFORE, in consideration of the foregoing and the mutual promises
and covenants herein contained and other good and valuable consideration the
receipt of which is hereby acknowledged, the parties agree as follows:

1.   EMPLOYMENT; DUTIES
     ------------------

     (A) The Corporation engages and employs the Employee, and the Employee
hereby accepts engagement and employment, as Senior Vice President, Research.

     (B) The Employee shall have such powers and perform all such duties as from
time to time may be assigned to him by the Board of Directors (the "Board"), the
Chairman of the Board, the Chief Executive Officer, or the President.

     (C) The Employee shall devote such of his time and efforts as shall be
necessary to the proper discharge of his duties and responsibilities under this
Agreement.

2.   TERM
     ----

     The Employee's employment hereunder shall be for the period commencing on
the date of this Agreement and continuing through August 31, 2004.

3.   COMPENSATION
     ------------

     (A) As compensation for the performance of his duties under this Agreement,
the Employee shall be compensated as follows:

          (i) The Employee shall be granted options to purchase shares of Common
Stock of the Corporation as deemed appropriate by the Board or its Compensation
Committee. To the maximum extent permitted by law, the stock options shall be
incentive stock options.

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Employee Agreement
Mark E. Furth, Ph.D.
Page 2

          (ii) The Corporation shall pay the Employee an annual base salary
("Base Salary") of two hundred forty thousand dollars ($240,000), payable in
accordance with the usual payroll period of the Corporation. Base Salary will be
adjusted periodically to reflect Employee's then current salary, which will be
subject to an annual review in the sole discretion of the Board of Directors or
its Compensation Committee, provided however, that the Base Salary may not be
adjusted downward.

          (iii) The Corporation shall pay the Employee bonuses, the amount of
which shall be in the discretion of the Corporation, upon the achievement of
substantial milestones to be mutually agreed upon from time to time by the Chief
Executive Officer, the Board of Directors or its Compensation Committee of the
Board.

          (iv) The Corporation shall withhold all applicable federal, state and
local taxes, social security and workers' compensation contributions and such
other amounts as may be required by law and any additional amounts agreed upon
by the parties with respect to the compensation payable to the Employee pursuant
to section 3(A) hereof.

     (B) The Corporation shall reimburse the Employee for all normal, usual and
necessary expenses incurred by the Employee in furtherance of the business and
affairs of the Corporation, including reasonable travel and entertainment,
against receipt by the Corporation of appropriate vouchers or other proof of the
Employee's expenditures and otherwise in accordance with such Expense
Reimbursement Policy as may from time to time be adopted by the Board of
Directors of the Corporation.

     (C) The Employee shall be, during the term of this Agreement, entitled to
vacation time of four (4) weeks per year.

     (D) The Corporation shall make available to the Employee and his
dependents, such medical, disability, life insurance and such other health
benefits as the Corporation makes available to its senior officers.

4.   REPRESENTATIONS AND WARRANTIES BY THE EMPLOYEE AND CORPORATION
     --------------------------------------------------------------

     The Employee hereby represents and warrants to the Corporation as follows:

     (A) Neither the execution and delivery of this Agreement nor the
performance by the Employee of his duties and other obligations hereunder
violate or will violate any statute, law, determination or award, or conflict
with or constitute a default under (whether immediately, upon the giving of
notice or lapse of time or both) any prior employment agreement, contract, or
other instrument to which the Employee is a party or by which he is bound.

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Employee Agreement
Mark E. Furth, Ph.D.
Page 3

     (B) The Employee has the full right, power and legal capacity to enter and
deliver this Agreement and to perform his duties and other obligations
hereunder. This Agreement constitutes the legal, valid and binding obligation of
the Employee enforceable against him in accordance with its terms. No approvals
or consents of any persons or entities are required for the Employee to execute
and deliver this Agreement or perform his duties and other obligations
hereunder.

     (C) The Employee understands that some or all of the stock issuable upon
exercise of the Options received by the Employee pursuant to section 3(A) hereof
may not be registered under the Securities Act of 1933 (the "1933 Act"), and
acknowledges that he may be obligated to agree, as a condition to the issuance
thereof, that he will acquire such stock for his own account for investment and
not with a view to, or for resale in connection with a distribution thereof, and
will bear the economic risk of his investment in such stock for an indefinite
period of time.

     (D) The Corporation hereby represents and warrants to the Employee as
follows:

          (i) The Corporation is duly organized, validly existing and in good
standing under the laws of the State of Delaware, with all requisite corporate
power and authority to own its properties and conduct its business in the manner
presently contemplated.

          (ii) The Corporation has full power and authority to enter into this
Agreement and to incur and perform its obligations hereunder.

          (iii) The execution, delivery and performance by the Corporation of
this Agreement does not conflict with or result in a breach or violation of, or
constitute a default under (whether immediately, upon the giving of notice or
lapse of time or both) the certificate of incorporation or by-laws of the
Corporation, or any agreement or instrument to which the Corporation is a party
or by which the Corporation or any of its properties may be bound or affected.

5.   NON-COMPETITION
     ---------------

     (A) The Employee understands and recognizes that his services to the
Corporation are special and unique and agrees that, during the term of this
Agreement and, unless such termination is by the Employee pursuant to 7(A)(iii)
below, for a period of six (6) months from the date of termination of his
employment hereunder, he shall not in any manner, directly or indirectly, on
behalf of himself or any person, firm, partnership, joint venture, corporation
or other business entity ("Person"), enter into or engage in any business
engaged in the development or commercialization of products directly competitive
with products of the Corporation, including products under development by the
Corporation, either as an individual for his own account, or as a partner, joint
venturer, executive, agent, consultant, salesperson, officer, director or
shareholder of a Person operating or intending to operate in the areas of
therapies focused on tissue protection, repair and regeneration, including
catalytic antioxidant molecules, adult liver

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Employee Agreement
Mark E. Furth, Ph.D.
Page 4

stem cell therapy for the treatment of liver failure and heparins for the
treatment of ulcerative colitis, or Corporation's future business, proposed
business or future research activities or any additional areas of business as
shall be updated from time to time by the parties to take into account
additional areas of business in which the Corporation may become engaged),
within the geographic area of the Corporation's business. This Paragraph 5(A)
shall not be construed to prohibit the ownership by Employee of not more than 1%
of the capital stock of any corporation engaged in any of the foregoing
businesses which has a class of securities registered pursuant to the Securities
Exchange Act of 1934.

     (B) During the term of this Agreement and for six (6) months thereafter,
Employee shall not, directly or indirectly, without the prior written consent of
the Corporation, solicit or induce any employee of the Corporation or any
affiliate to leave the employ of the Corporation or any affiliate or hire for
any purpose any employee of the Corporation or any affiliate or any employee who
has left the employment of the Corporation or any affiliate within six months of
the termination of said employee's employment with the Corporation; or

     (C) In the event that the Employee breaches any provisions of this Section
5 or there is a threatened breach, then, in addition to any other rights which
the Corporation may have, the Corporation shall be entitled to seek injunctive
relief to enforce the restrictions contained herein. In the event that an actual
proceeding is brought in equity to enforce the provisions of this Section 5, the
Corporation shall not be prevented from seeking any other remedies which may be
available.

6.   CONFIDENTIALITY AND INVENTIONS
     ------------------------------

     Employee agrees to comply with the provisions of his Employee Agreement
dated September 4, 2001 signed at the commencement of employment, which
provisions are incorporated herein by reference and are made part of this
Agreement as if they were explicitly set forth herein.

7.   TERMINATION
     -----------

     (A) The Employee's employment pursuant to this Agreement shall continue for
the period set forth in Section 2 hereof unless sooner terminated upon the first
to occur of the following events:

          (i) The death of the Employee;

          (ii) Termination by the Board of Directors of the Corporation for
cause. Any of the following actions by the Employee shall constitute cause:

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Employee Agreement
Mark E. Furth, Ph.D.
Page 5

               (a) Material breach by the Employee of Section 5 or Section 6 of
this Agreement;

               (b) Material breach by the Employee of any provision of this
Agreement other than Section 5 or Section 6 or the willful or reckless failure
by Employee to perform his duties hereunder which breach or failure is not cured
by the Employee within fifteen (15) days notice thereof from the Corporation; or

               (c) The commission by the Employee of an act of fraud or theft
against the Corporation or any of its subsidiaries, or the conviction of
Employee of any criminal act;

          (iii) Termination by the Employee for cause. Material breach by the
Corporation of any provision of this Agreement which is not cured by the
Corporation within fifteen (15) days of written notice thereof from the Employee
shall constitute cause; or

          (iv) Termination by the Board of Directors, the President, or the
Chief Executive Officer of the Corporation without cause.

     (B) Upon termination without cause pursuant to Section 7(A)(iv) or by
Employee for cause pursuant to Section 7(A)(iii) or upon termination resulting
from Employee's death pursuant to Section 7(A)(i), Employee (or his estate in
the event of a termination pursuant to Section 7(A)(i)) will be entitled to the
following:

          (i) all vested compensation then due and owing;

          (ii) as of the date of the termination, at the option of the
Corporation, the Corporation will pay either (i) a lump sum equal to fifty
percent (50%) of Employee's then current Base Salary, or (ii) six (6) equal
monthly payments equal to the total sum of fifty percent (50%) of the Employee's
then current Base Salary; and

          (iii) Corporation will continue to pay for his, or his heirs', COBRA
premiums and the premium for his executive disability insurance coverage, if
applicable, for a period of six (6) months commencing as of the date of
termination.

     (C) Employee may terminate his employment with the Corporation at any time,
without cause, upon two weeks written notice to his supervisor. In such event,
Employee shall not be entitled to any benefits under this Agreement, but shall
be entitled upon termination to such benefits, if any, as are granted by law or
pursuant to the Corporation's policies, in each case, as in effect on the date
the notice of termination is given by Employee.

     (D) Termination of employment under this Agreement by either party, for any
reason, shall not affect the Employee's obligations under Sections 5 and 6
hereof, all of which shall survive such termination in accordance with their
respective terms.

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Employee Agreement
Mark E. Furth, Ph.D.
Page 6

8.   NOTICES
     -------

     Any notice or other communication under this Agreement shall be in writing
and shall be deemed to have been given: when delivered personally against
receipt therefor; one (1) day after being sent by Federal Express or similar
overnight delivery; or three (3) days after being mailed registered or certified
mail, postage prepaid, return receipt requested, to either party at the address
set forth above, or to such other address as such party shall give by notice
hereunder to the other party.

9.   RENEWAL OF AGREEMENT
     --------------------

     Upon expiration of the term of this Agreement, this agreement may be
renewed for additional one (1) year periods by the parties by mutual written
agreement.

10.  SEVERABILITY OF PROVISIONS
     --------------------------

     If any provision of this Agreement shall be declared by a court of
competent jurisdiction to be invalid, illegal or incapable of being enforced in
whole or in part, such provision shall be interpreted so as to remain
enforceable to the maximum extent permissible consistent with applicable law and
the remaining conditions and provisions or portions thereof shall nevertheless
remain in full force and effect and enforceable to the extent they are valid,
legal and enforceable, and no provision shall be deemed dependent upon any other
covenant or provision unless so expressed herein.

11.  ENTIRE AGREEMENT MODIFICATION
     -----------------------------

     This Agreement contains the entire agreement of the parties relating to the
subject matter hereof, and the parties hereto have made no agreements,
representations or warranties relating to the subject matter of this Agreement
which are not set forth herein. No modification of this Agreement shall be valid
unless made in writing and signed by the parties hereto.

12.  BINDING EFFECT
     --------------

     The rights, benefits, duties and obligations under this Agreement shall
inure to, and be binding upon, the Corporation, its successors and assigns, and
upon the Employee and his legal representatives. This Agreement constitutes a
personal service agreement, and the performance of the Employee's obligations
hereunder may not be transferred or assigned by the Employee.

13.  NON-WAIVER
     ----------

     The failure of either party to insist upon the strict performance of any of
the terms, conditions and provisions of this Agreement shall not be construed as
a waiver or relinquishment

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Employee Agreement
Mark E. Furth, Ph.D.
Page 7

of future compliance therewith, and said terms, conditions and provisions shall
remain in full force and effect. No waiver of any term or condition shall be
effective for any purpose whatsoever unless such waiver is in writing and signed
by such party.

14.  GOVERNING LAW
     -------------

     This Agreement shall be governed by, and construed and interpreted in
accordance with, the laws of the State of Delaware without regard to principles
of conflict of laws.

15.  HEADINGS
     --------

     The headings of paragraphs are inserted for convenience and shall not
affect an interpretation of this Agreement.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the later of the following dates.

INCARA PHARMACEUTICALS
CORPORATION

By: /s/ Clayton I. Duncan                       /s/ Mark E. Furth
    -----------------------------------------   --------------------------------
Name:   Clayton I. Duncan                       MARK E. FURTH, PH.D.
Title:  President and Chief Executive Officer

Date:   May 8, 2002                             Date: May 8, 2002<PAGE>

                                                                   EXHIBIT 10.81

                               SEVERANCE AGREEMENT

     THIS SEVERANCE AGREEMENT (the "Agreement") is made as of May 8, 2002
                                    ---------
between INCARA PHARMACEUTICALS CORPORATION, a Delaware corporation (the
"Company"), and Mark E. Furth ("Employee").
 -------                        --------

                                    Recitals
                                    --------

A.   Employee is employed by the Company as an officer, and as such, the Company
     recognizes the valuable services performed by Employee for the Company and
     wishes to encourage his/her continued employment.

B.   Employee desires to be assured that he/she will be entitled to a certain
     amount of compensation and benefits for some definite period of time upon
     the occurrence of certain events.

C.   The parties desire to enter into this Agreement to provide the terms and
     conditions upon which the Company will pay severance benefits to Employee
     upon the occurrence of certain events.

                             Statement of Agreement
                             ----------------------

     In consideration of the foregoing and the promises and covenants contained
herein, and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereby agree as follows:

1.   Definitions. Whenever used in this Agreement, the following terms shall
     -----------
     have the meanings respectively assigned to them in this Section 1:

     (a) "Cause" shall have the meaning as defined in the Employment Agreement
          -----
     (as defined below), and in addition, shall include conviction of a felony
     and the violation of "insider trading laws", as determined by the
     Securities and Exchange Commission.

     (b) "Change in Control" means any of the following events or transactions:
          -----------------

          (i)  A merger or consolidation of the Company with another corporation
               (A) where the stockholders of the Company immediately prior to
               the merger or consolidation do not beneficially own, immediately
               after the merger or consolidation, shares of the corporation
               issuing cash or securities in the merger or consolidation
               entitling such stockholders to more than fifty percent (50%) of
               all votes (without consideration of the rights of any class of
               stock to elect directors by a separate class vote) to which all
               stockholders of such surviving corporation would be entitled in
               the election of directors, or (B) where the members of the Board
               of Directors of the Company immediately prior to the merger or
               consolidation do not, immediately after the merger or
               consolidation,

<PAGE>

               constitute a majority of the Board of Directors of the
               corporation issuing cash or securities in the merger or
               consolidation;

          (ii) The sale, transfer or other disposition of all or substantially
               all of the assets of the Company; or

          (iii) The acquisition, directly or indirectly, by any person or
               related group of persons (other than the Company or a person that
               directly or indirectly controls, is controlled by, or is under
               common control with, the Company) of beneficial ownership (within
               the meaning of Rule 13d-3 of the Securities Exchange Act of 1934,
               as amended) of securities possessing more than fifty percent
               (50%) of the total combined voting power of the Company's
               outstanding securities pursuant to a tender or exchange offer
               made directly to the Company's stockholders.

     (c)  "Employment Agreement" shall mean the Employment Agreement between the
           --------------------
          Employee and the Company dated May 8, 2002 (or any subsequent
          employment agreement which supplements, supersedes or replaces such
          agreement).

     (d)  "Good Reason" shall mean any reduction, without Employee's consent, in
           -----------
          Employee's status, title, authority, duties, salary, benefits,
          eligibility for bonuses or location of employment that is more than
          thirty (30) miles from Employee's current location of employment.

     (e)  "Separation Event" shall mean the termination by the Company of
           ----------------
          Employee's employment without Cause or termination by Employee for
          Good Reason, in either case within two and one-half years after the
          earliest date of a Change in Control of the Company (the "Termination
                                                                    -----------
          Period"). The death or disability of Employee shall not be a
          ------
          Separation Event.

     Other terms used in this Agreement are defined in other provisions of this
Agreement and shall have the respective meanings given such terms in those
provisions.

2.   Employment. Employee shall, so long as he/she remains in the active
     ----------
     employment of the Company, devote such of his/her time and efforts as shall
     be necessary to the proper discharge of his/her duties and responsibilities
     as an officer of the Company.

3.   Severance Benefits.
     ------------------

     (a)  In consideration of Employee remaining an employee of the Company, if
          there is a Separation Event, then Employee shall receive the following
          in lieu of any other severance benefits due to Employee pursuant to
          Company policies or the Employment Agreement, if any.

<PAGE>

          (i)  Accrued and unpaid salary less all applicable and customary
               withholding taxes and deductions;

          (ii) A bonus in the amount of the average annual bonus earned by
               Employee during the previous two years, prorated for the portion
               of the current year worked through the date of termination, less
               all applicable withholding taxes and deductions;

          (iii) A lump sum severance payment equal to two and one-half times the
               sum of his/her current annual base salary and average annual
               bonus during the previous two years, less all applicable
               withholding taxes and deductions; and

          (iv) Medical and insurance benefits paid by the Company or its
               successor-in-interest equal to those provided by the Company to
               Employee immediately prior to the date of the Separation Event
               for two and one-half years following the Separation Event.

     (b)  The amounts in Subsections 3(a)(i), (ii) and (iii) shall be paid
          within thirty (30) days following the Separation Event.

     (c)  In addition to the foregoing, all restricted stock and all stock
          options for the purchase of capital stock of the Company held by
          Employee shall vest in full immediately upon the occurrence of a
          Separation Event.

4.   Other Termination of Employment. If the Company or the Employee terminates
     -------------------------------
     Employee's employment with the Company for any reason other than a
     Separation Event, then

          (i)  No benefits shall become due and payable under Section 3, above;

          (ii) This Agreement shall be considered terminated with respect to
               Employee; and

          (iii) Company policy and the Employment Agreement shall determine the
               severance benefits, if any, due to Employee or his/her
               descendents.

5.   Corporate Assets. No provision in this Agreement, or any action taken
     ----------------
     pursuant to its provisions by either party, shall create, or be construed
     to create, a trust of any kind, or a fiduciary relationship between the
     Company and the Employee, his/her designated beneficiary, other
     beneficiaries of Employee, or any other person. The payments to Employee,
     his/her designated beneficiary, or any other beneficiary shall be made from
     assets which shall continue to be a part of the general assets of the
     Company. No person shall have, by virtue of the provisions of this
     Agreement, any interest in the Company's assets. To the extent that any
     person acquires a right to receive payments or benefits from the Company
     under this Agreement, the right shall be no greater than the right of any
     unsecured general creditor of the Company.

<PAGE>

6.   No Employment Contract. Nothing contained in this Agreement shall be
     ----------------------
     construed as a contract of employment for any term of years, nor as
     conferring upon Employee the right to continue as an employee of the
     Company in any capacity. It is understood by the parties that this
     Agreement relates exclusively to severance benefits payable after
     termination of Employee's employment with the Company during the
     Termination Period, and is not intended to be an employment contract.

7.   Employee's Capacity. Employee represents and warrants to the Company that
     -------------------
     he/she has the capacity and right to enter into this Agreement without any
     restriction whatsoever by any other agreement, other document or otherwise.

8.   Complete Agreement. This document contains the entire agreement between the
     ------------------
     parties regarding severance arrangements resulting from certain
     terminations of Employee's employment during the Termination Period and
     supersedes any prior discussions, negotiations, representations, or
     agreements between them relating to such severance arrangements for
     Employee. No additions or other changes to this Agreement shall be made or
     be binding on either party unless made in writing and signed by each party
     to this Agreement.

9.   Notices. All notices and other communications under this Agreement to any
     -------
     party shall be in writing and shall be deemed given when delivered
     personally, via facsimile (which is confirmed) to that party at the
     telecopy number for that party set forth below, mailed by certified mail
     (return receipt requested) to that party at the address for that party set
     forth below (or at such other address for such party as such party shall
     have specified in notice to the other party), or delivered to Federal
     Express, UPS or any similar express delivery service for delivery to that
     party at that address:

          (a)  If to the Company:

               Incara Pharmaceuticals Corporation
               P.O. Box 14287
               79 T.W. Alexander Drive
               4401 Research Commons, Suite 200
               Research Triangle Park, NC  27709
               Attention: President
               Facsimile No.: (919) 544-1245

          (b)  If to the Employee:

               The Employee's current address in the Company's personnel files

10.  Governing Law. All questions concerning the validity, intention, or meaning
     -------------
     of this Agreement or relating to the rights or obligations of the parties
     with respect to performance hereunder shall be construed and resolved under
     the laws of North Carolina.

<PAGE>

11.  Severability. The intention of the parties to this Agreement is to comply
     ------------
     fully with all laws and public policies, and this Agreement shall be
     construed consistently with all laws and public policies to the extent
     possible. If and to the extent that any court of competent jurisdiction
     determines that it is impossible or violative of any legal prohibition to
     construe any provision of this Agreement consistently with any law, legal
     prohibition, or public policy and consequently holds that provision to be
     invalid or prohibited, that shall in no way affect the validity of the
     other provisions of this Agreement which shall remain in full force and
     effect.

12.  Nonwaiver. No failure by any party to insist upon strict compliance with
     ---------
     any term of this Agreement, to exercise any option, enforce any right, or
     seek any remedy upon any default of any other party shall affect, or
     constitute a waiver of, the first party's right to insist upon such strict
     compliance, exercise that option, enforce that right, or seek that remedy
     with respect to that default or any prior, contemporaneous, or subsequent
     default; nor shall any custom or practice of the parties at variance with
     any provision of this Agreement affect or constitute a waiver of, any
     party's right to demand strict compliance with all provisions of this
     Agreement.

13.  Captions. The captions of the various sections of this Agreement are not
     --------
     part of the context of this Agreement, but are only labels to assist in
     locating those sections, and shall be ignored in construing this Agreement.

14.  Successors. This Agreement shall be personal to Employee and no rights or
     ----------
     obligations of Employee under this Agreement may be assigned by him/her.
     Except as described in the preceding sentence, this Agreement shall be
     binding upon, inure to the benefit of, and be enforceable by and against
     the respective heirs, legal representatives, successors, and assigns of
     each party to this Agreement.

     IN WITNESS WHEREOF, the parties hereto have executed this Severance
Agreement as of the date and year first above written.

                                           INCARA PHARMACEUTICALS CORPORATION

                                           By: /s/ Clayton I. Duncan
                                               ---------------------------------
                                           Title:  Chairman and CEO

                                           EMPLOYEE:

                                           /s/ Mark E. Furth              (SEAL)
                                           -------------------------------
                                           Mark E. Furth

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