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                                                                    Exhibit 10.2
                                                                    ------------

                              RESIGNATION AGREEMENT
                              ---------------------

                  THIS RESIGNATION AGREEMENT (this "Agreement"), is made,
entered into and effective as of September 25, 2000 (the "Resignation Date"), by
and between Gliatech Inc. (the "Company"), located at 23420 Commerce Park Road,
Cleveland, Ohio 44122 and Michael A. Zupon ("Executive"), residing at 9915 Music
Street, Novelty, Ohio 44065.

                                   WITNESSETH:
                                   -----------

                  WHEREAS, prior to the Resignation Date, Executive was the
Executive Vice President of Research and Development of the Company;

                  WHEREAS, Executive has determined that, effective on the
Resignation Date, he shall resign as an employee of the Company, and from any
and all offices of the Company, and any other position, office or directorship
of any other entity for which Executive was serving at the request of the
Company; and

                  WHEREAS, the Company accepts Executive's resignation as of the
date referenced above; and

                  WHEREAS, the Company and Executive desire to set forth the
payments and benefits that Executive will be entitled to receive from the
Company and the continuing obligations that each party has undertaken in
connection with the cessation of Executive's employment with the Company; and

                  WHEREAS, the Company and Executive wish to resolve, settle
and/or compromise certain matters, claims and issues between them, including,
without limitation, Executive's resignation from the offices he held and from
his employment with the Company.

                  NOW, THEREFORE, in consideration of the promises and
agreements contained herein and other good and valuable consideration, the
sufficiency and receipt of which are hereby acknowledged, and intending to be
legally bound, the Company and Executive hereby agree as follows:

         1. RESIGNATION. Executive hereby resigns, effective on the Resignation
Date, his employment with the Company and its subsidiaries and related or
affiliated companies, and his position as Executive Vice President of Research
and Development of the Company. Executive further resigns, effective on the
Resignation Date: (a) from all other offices of the Company to which he has been
elected by the Board of Directors of the Company (or to which he has otherwise
been appointed), (b) from all offices of any entity that is a subsidiary of, or
is otherwise related to or affiliated with, the Company, (c) from all
administrative, fiduciary or other positions he may hold with respect to
arrangements or plans for, of or relating to the Company, and (d) from any other
directorship, office, or position of any corporation, partnership, joint
venture, trust or other enterprise (each, an "Other Entity") insofar as
Executive is serving in




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the directorship, office, or position of the Other Entity at the request of the
Company. The Company hereby consents to and accepts said resignations.

         2. COMPENSATION AND BENEFITS. Subject to the conditions hereof, the
Company and Executive agree to the following:

                  a. SEVERANCE COMPENSATION. As severance compensation, the
Company shall pay Executive an amount equal to the Executive's annual base
salary of $180,000 in effect immediately before the Resignation Date. Such
amount shall be paid one-half on the day after which Executive's right of
revocation under Subparagraph 5.c.(iv) of this Agreement expires (the "First
Payment Date"), and one-half on the date that is six months after the
Resignation Date.

                  b. STOCK OPTIONS. Executive has certain stock options that
were granted to Executive prior to the date of his resignation. Executive's
eligibility to exercise these vested and exercisable options is governed by the
terms and conditions of the Company's Amended and Restated 1989 Stock Option
Plan and the agreements previously entered into between the Company and the
Executive with respect to such stock options. Notwithstanding the foregoing, (i)
any stock options that were granted to Executive as of the Resignation Date that
are not vested shall continue to vest pursuant to the vesting schedule set forth
in the agreements governing such stock options for a period of one year after
the Resignation Date (the "Vesting Date"), and (ii) Executive shall have a
period of fifteen months following the Resignation Date (the "Benefit Period")
in which to exercise or forfeit vested options. Executive agrees and
acknowledges that he is ineligible for any other stock options, grants or
awards, and that he forfeits upon the Resignation Date any rights in or to any
other stock option grants, including without limitation, any right to vest after
the Vesting Date in any stock options that are not already vested as of the
Vesting Date.

                  c. MEDICAL COVERAGE.

                           (i) Executive shall be allowed to continue as a plan
         participant in the Company's group health plan (medical, dental and
         vision coverage) (the "Health Plan") for a period of one year following
         the Resignation Date (the "Severance Period") on the same basis that
         the Company's active employees participate in such plan during that
         period.

                           (ii) For a period of six months following the end of
         the Severance Period, Executive may continue, at his cost, his
         participation in the Health Plan pursuant to the health care
         continuation coverage requirements of federal law.

                  d. PROFESSIONAL FEES. The Company and Executive acknowledge
and agree that each shall be responsible for the payment of their respective
legal fees and costs (and related disbursements) incurred in connection with
Executive's resignation and all matters relating to the negotiation and
execution of the releases and all other matters covered by this Agreement.

                  e. COMPANY BENEFIT PLANS. Except as provided above in Section
2.c of this Agreement, Executive's post-Resignation Date eligibility for
benefits, if any, as a past employee of the Company under the Company's
retirement and welfare benefit plans shall be as set forth in the respective
plan documents and shall be based on his employment termination on the




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Resignation Date, and his entitlement to benefits for the period of his
participation therein shall be determined pursuant to the terms thereof.

                  f. BUSINESS EXPENSES. The Company will reimburse Executive for
any reasonable business expenses incurred by Executive prior to the Resignation
Date that are reimbursable pursuant to the Company's expense reimbursement
policies.

                  g. VACATION PAY. Executive shall be paid for accrued but
unused vacation time determined as of the Resignation Date, with such payment to
be made on the First Payment Date.

                  h. ACCRUED SALARY. Executive shall be paid in accordance with
the Company's normal payroll cycle any base salary amount earned but unpaid as
of the Resignation Date.

                  i. OUTPLACEMENT. Executive shall be entitled to reimbursement
by the Company for the costs of outplacement services utilized by Executive
after the Resignation Date up to $14,000 in total, promptly after Executive
provides receipts or other documentation establishing that he has incurred such
costs and the amount thereof.

                  j. WITHHOLDING. The Company shall withhold such amounts from
the payments described herein as are required by applicable tax or other law.

                  k. LIFE INSURANCE. If requested, the Company will transfer to
Executive ownership of any life insurance policy on Executive's life owned by
the Company, upon Executive's payment to the Company of the current cash value,
if any, of such policy.

                  l. TAX PLANNING. Executive shall be entitled to reimbursement
up to $3,000 for tax planning services for the year 2000 pursuant to the
Company's reimbursement policy with respect to such services.

                  m. REFERENCES. The Company shall provide to any potential
future employer of Executive which requests information from the Company with
respect to Executive, the period of Executive's employment with the Company and
his title with the Company.

         3. NON-COMPETITION.

                  a. During the Benefit Period, Executive shall not, directly or
indirectly, do or suffer to be done any of the following: own, manage, control
or participate in the ownership, management, or control of, or be employed or
engaged by or otherwise affiliated or associated as a consultant, independent
contractor or otherwise with any other corporation, partnership, proprietorship,
firm, association, or other business entity, or otherwise engage in any
business, which is in competition with the Company's business in the United
States; provided, however, that the ownership of not more than one percent of
any class of publicly-traded securities of any entity shall not be deemed a
violation of this Agreement. For purposes of this Agreement, the "Company's
business" shall mean any business in which the Company actively engages now, and
any business in which the Company has actively engaged in the two (2) year
period prior to the date hereof, including, without limitation, the discovery
and development of (i) products



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designed to inhibit post surgical scarring and adhesions, a proprietary
monoclonal antibody to treat anti-inflammatory disorders, and (iii) small
molecule drug candidates to the modulate cognitive state of the nervous system
and to treat symptoms of schizophrenia.

                  b. In the event Executive shall violate any provision of this
Paragraph 3 as to which there is a specific time period during which he is
prohibited from taking certain actions or from engaging in certain activities as
set forth in such provision, then, in such event, such violation shall toll the
running of such time period from the date of such violation until such violation
shall cease. The foregoing shall in no way limit the Company's rights under
Paragraph 8 of this Agreement.

                  c. Executive has carefully considered the nature and extent of
the restrictions upon him and the rights and remedies conferred upon the Company
under this Paragraph 3 and this Agreement, and hereby acknowledges and agrees
that the same are reasonable in time and territory, are designed to eliminate
competition which otherwise would be unfair to the Company, do not stifle the
inherent skill and experience of Executive, would not operate as a bar to
Executive's sole means of support, are fully required to protect the legitimate
interests of the Company and do not confer a benefit upon the Company
disproportionate to the detriment of Executive. Executive further acknowledges
that his obligations in this Paragraph 3 are made in consideration of, and are
adequately supported by the payments by the Company to Executive described
herein.

         4. NO SOLICITATION OF EMPLOYEES. Executive agrees that he will not:

                  (i) Employ, assist in employing, or otherwise associate in
         business with any person who is, or has been in the 12 month period
         prior to such individual's association with Executive an employee,
         officer or agent of the Company, or any of its affiliated, related or
         subsidiary entities, unless such employee was involuntarily terminated
         by the Company, provided that Executive's employment with a subsequent
         employer that also employs other former employees of the Company shall
         not constitute a breach of this Paragraph 4, if such other former
         employee's employment with such subsequent employer did not result from
         a breach of this Paragraph 4.

                  (ii) Induce any person who is an employee, officer or agent of
         the Company, or any of its affiliated, related, or subsidiary entities
         to terminate such relationship.

         5. RELEASE BY EXECUTIVE.

                  a. Executive for himself and his dependents, successors,
assigns, heirs, executors and administrators (and his and their legal
representatives of every kind), hereby releases, dismisses, remisses and forever
discharges the Company from any and all arbitrations, claims (including claims
for attorney's fees), demands, damages, suits, proceedings, actions and/or
causes of action of any kind and every description, whether known or unknown,
which Executive now has or may have had for, upon, or by reason of any cause
whatsoever (except that this release shall not apply to (i) the obligations of
the Company arising under this Agreement, (ii) benefits to which Executive is
entitled under benefit plans of the Company that are subject to the Employee
Retirement Income Security Act of 1974, as amended and (iii) Executive's rights



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of indemnification by the Company, if any, pursuant to any agreement between the
Company and Executive, against the Company ("claims"), including but not limited
to:

                  (i) any and all claims, directly or indirectly, arising out of
         or relating to: (A) Executive's past employment or service with the
         Company; and (B) Executive's resignation as Executive Vice President of
         Research and Development and any other position described in Paragraph
         1 of this Agreement.

                  (ii) any and all claims of discrimination, including but not
         limited to claims of discrimination on the basis of sex, race, age,
         national origin, marital status, religion or disability, including,
         specifically, but without limiting the generality of the foregoing, any
         claims under the Age Discrimination in Employment Act, as amended (the
         "ADEA"), Title VII of the Civil Rights Act of 1964, as amended, the
         Americans with Disabilities Act of 1990, the Family and Medical Leave
         Act of 1993 and Ohio Revised Code Chapter 4112;

                  (iii) any and all claims of wrongful or unjust discharge or
         breach of any contract or promise, express or implied; and

                  (iv) any and all claims under or relating to any and all
         employee compensation, employee benefit, employee severance or employee
         incentive bonus plans and arrangements, all of which Executive agrees
         are forfeited upon his resignation; provided that he shall remain
         entitled to the amounts and benefits described in Paragraph 2 above.
         Executive agrees that he intends to release any and all workers
         compensation claims he may have against the Company by this Agreement,
         and further agrees to execute any documentation as may be reasonably
         required to perfect such release when presented to him by the Company.

                  b. Executive understands and acknowledges that the Company
does not admit any violation of law, liability or invasion of any of his rights
and that any such violation, liability or invasion is expressly denied. The
consideration provided under this Agreement is made for the purpose of settling
and extinguishing all claims and rights (and every other similar or dissimilar
matter) that Executive ever had or now may have or ever will have against the
Company to the extent provided in this Paragraph 5. Executive further agrees and
acknowledges that no representations, promises or inducements have been made by
the Company other than as appear in this Agreement.

                  c. Executive further understands and acknowledges that:

                  (i) The release provided for in this Paragraph 5, including
         claims under the ADEA to and including the date of this Agreement, is
         in exchange for the additional consideration provided for in this
         Agreement, to which consideration he was not heretofore entitled;

                  (ii) He has been advised by the Company to consult with legal
         counsel prior to executing this Agreement and the release provided for
         in this Paragraph 5, has had an opportunity to consult with and to be
         advised by legal counsel of his choice, fully



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         understands the terms of this Agreement, and enters into this Agreement
         freely, voluntarily and intending to be bound;

                  (iii) He has been given a period of twenty-one days to review
         and consider the terms of this Agreement, and the release contained
         herein, prior to its execution and that he may use as much of the
         twenty-one day period as he desires; and

                  (iv) He may, within seven days after execution, revoke this
         Agreement. Revocation shall be made by delivering a written notice of
         revocation to the Chief Operating Officer at the Company. For such
         revocation to be effective, written notice must be actually received by
         the Chief Operating Officer at the Company no later than the close of
         business on the seventh day after Executive executes this Agreement. If
         Executive does exercise his right to revoke this Agreement, all of the
         terms and conditions of the Agreement shall be of no force and effect
         and the Company shall have no obligation to satisfy the terms or make
         any payment to Executive as set forth in Paragraph 2 of this Agreement.

                  d. Executive will never file a lawsuit or other complaint
asserting any claim that is released in this Paragraph 5.

                  e. Executive and the Company acknowledge that his resignation
is by mutual agreement between the Company and Executive, and that Executive
waives and releases any claim that he has or may have to reemployment.

                  f. For purposes of the above provisions of this Paragraph 5,
the "Company" shall include its present and former predecessors, subsidiaries,
divisions, related or affiliated companies, officers, directors, stockholders,
members, employees, heirs, successors, assigns, representatives, agents,
accountants and counsel.

         6. CONFIDENTIAL INFORMATION.

                  a. Executive acknowledges and agrees that in the performance
of his duties as an officer and employee of the Company he was brought into
frequent contact with, had or may have had access to, and/or became informed of
confidential and proprietary information of the Company and/or information which
is a competitive asset of the Company (collectively, "Confidential Information")
and the disclosure of which would be harmful to the interests of the Company or
its subsidiaries. Confidential Information shall include, without limitation:
(a) customer and distributor information such as names, addresses, sales
histories, purchasing habits, credit status, pricing levels, etc., (b) certain
prospective customer and distributor information lists, etc., (c) product and
systems specifications, schematics, designs, concepts for new or improved
products and services and other products and services data, (d) product and
material costs, (e) suppliers' and prospective suppliers' names, addresses and
contracts, (f) future corporate planning data, (g) production methods and
equipment, (h) marketing strategies, (i) the Company's financial results and
business condition, (j) any of the foregoing which belong to any other person or
company but to which Executive has had access by reason of his employment with
the Company, (k) pre-clinical and clinical testing procedures and other related
information, and (l) any other information which constitutes a "trade secret"
under federal or state law. Such



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Confidential Information is more fully described in Subparagraph (b) of this
Paragraph 6. Executive acknowledges that the Confidential Information of the
Company gained by Executive during his association with the Company was
developed by and/or for the Company through substantial expenditure of time,
effort and money and constitutes valuable and unique property of the Company.
Notwithstanding the above, Confidential Information shall not include any
information that Executive acquired prior to his employment with the Company or
that is generally known in the industry.

                  b. Executive will keep in strict confidence, and will not,
directly or indirectly, at any time, disclose, furnish, disseminate, make
available, use or suffer to be used in any manner any Confidential Information
of the Company without limitation as to when or how Executive may have acquired
such Confidential Information. Executive specifically acknowledges that
Confidential Information includes any and all information, whether reduced to
writing (or in a form from which information can be obtained, translated, or
derived into reasonably usable form), or maintained in the mind or memory of
Executive and whether compiled or created by the Company, which derives
independent economic value from not being readily known to or ascertainable by
proper means by others who can obtain economic value from the disclosure or use
of such information, that reasonable efforts have been put forth by the Company
to maintain the secrecy of confidential or proprietary or trade secret
information, that such information is and will remain the sole property of the
Company, and that any retention or use by Executive of confidential or
proprietary or trade secret information after the termination of Executive's
employment with and services for the Company shall constitute a misappropriation
of the Company's Confidential Information.

                  c. Executive will immediately return to the Company (to the
extent he has not already returned), equipment, software, electronic files,
computers, including any laptop, in good condition, all property of the Company,
including, without limitation, property, documents and/or all other materials
(including copies, reproductions, summaries and/or analyses) which constitute,
refer or relate to Confidential Information of the Company.

                  d. Executive further acknowledges that his obligation of
confidentiality shall survive, regardless of any other breach of this Agreement
or any other agreement, by any party hereto, until and unless such Confidential
Information of the Company shall have become, through no fault of Executive
generally known to the public or Executive is required by law (after providing
the Company with notice and opportunity to contest such requirement) to make
disclosure. Executive's obligations under this Paragraph 6 are in addition to,
and not in limitation or preemption of, all other obligations of confidentiality
which Executive may have to the Company under general legal or equitable
principles or statutes.

         7. DISCLOSURE.

                  a. From the date of this Agreement through the end of the
Severance Period, Executive will communicate the contents of Paragraphs 3, 4, 6,
8.b., 9 and 11 of this Agreement to any person, firm, association, or
corporation other than the Company which he intends to be employed by,
associated in business with, or represent.




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                  b. Executive shall take no action with respect to the
Company's common stock that is in violation of the Company's policies with
respect to the trading in common stock or the federal securities laws.

         8. BREACH.

                  a. If Executive breaches any of the provisions of this
Agreement (and in the case of a breach that is capable of being cured, fails to
cure such breach within fifteen days after written notice by the Company to
Executive specifying the circumstances that constitute such breach), then the
Company may, at its sole option, immediately terminate all remaining payments
and benefits described in this Agreement, including the vesting or
exercisability of any stock options under Paragraph 2.b., and obtain
reimbursement from Executive of all payments and benefits already provided
pursuant to Paragraph 2 of this Agreement, plus any expenses and damages
incurred as a result of the breach (including, without limitation, reasonable
attorneys' fees), with the remainder of this Agreement, and all promises and
covenants herein, remaining in full force and effect.

                  (i) Notwithstanding the foregoing, the Company will not
         terminate pursuant to Paragraph 8.a. above any benefits to which
         Executive is entitled under any tax-qualified retirement plan of the
         Company, and Executive's rights under Part 6 of Subtitle B of Title I
         of the Employee Retirement Income Security Act of 1974 as amended, if
         any, will not be reduced by any action taken by the Company under
         Paragraph 8.a. above.

                  (ii) Executive may challenge any Company action under
         Paragraph 8.a. above.

                  b. Executive acknowledges and agrees that the remedy at law
available to the Company for breach by Executive of any of his obligations under
Paragraphs 3, 4, 6 and 7 of this Agreement would be inadequate and that damages
flowing from such a breach would not readily be susceptible to being measured in
monetary terms. Accordingly, Executive acknowledges, consents and agrees that,
in addition to any other rights or remedies which the Company may have at law,
in equity or under this Agreement, upon adequate proof of Executive's violation
of any provision of Paragraphs 3, 4 or 6 of this Agreement, the Company shall be
entitled to immediate injunctive relief and may obtain a temporary order
restraining any threatened or further breach, without the necessity of proof of
actual damage.

         9. CONTINUED AVAILABILITY AND COOPERATION.

                  a. Executive shall cooperate fully with the Company, with the
Company's counsel, and with the Company's insurer in connection with any present
and future actual or threatened litigation or administrative proceeding
involving the Company that relates to events, occurrences or conduct occurring
(or claimed to have occurred) during the period of Executive's employment by the
Company. This cooperation by Executive shall include, but not be limited to:

                  (i) making himself reasonably available for interviews and
         discussions with the Company's counsel as well as for depositions and
         trial testimony;



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                  (ii) if depositions or trial testimony are to occur, making
         himself reasonably available and cooperating in the preparation
         therefor as and to the extent that the Company or the Company's counsel
         reasonably requests;

                  (iii) refraining from impeding in any way the Company's
         prosecution or defense of such litigation or administrative proceeding;
         and

                  (iv) cooperating fully in the development and presentation of
         the Company's prosecution or defense of such litigation or
         administrative proceeding.

                  b. Executive shall be reimbursed by the Company for reasonable
travel, lodging, telephone and similar expenses incurred in connection with such
cooperation, which the Company shall reasonably endeavor to schedule at times
not conflicting with the reasonable requirements of any employer of Executive,
or with the requirements of any third party with whom Executive has a business
relationship permitted hereunder that provides remuneration to Executive.
Executive shall not unreasonably withhold his availability for such cooperation.
Executive shall not be entitled to compensation from the Company for such
cooperation during the Benefit Period, and shall be compensated at a reasonable
hourly rate mutually agreed to by Executive and the Company for such cooperation
following the Benefit Period.

         10. SUCCESSORS AND BINDING AGREEMENT.

                  a. This Agreement shall be binding upon and inure to the
benefit of the Company and any successor of or to the Company, including,
without limitation, any persons acquiring, directly or indirectly, all or
substantially all of the business and/or assets of the Company whether by
purchase, merger, consolidation, reorganization, or otherwise (and such
successor shall thereafter be deemed included in the definition of "the Company"
for purposes of this Agreement), but shall not otherwise be assignable or
delegable by the Company.

                  b. This Agreement shall inure to the benefit of and be
enforceable by Executive's personal or legal representatives, executors,
administrators, successors, heirs, distributees, and/or legatees.

                  c. This Agreement is personal in nature and none of the
parties hereto shall, without the consent of the other parties, assign, transfer
or delegate this Agreement or any rights or obligations hereunder except as
expressly provided in Subparagraphs (a) and (b) of this Paragraph 10.

                  d. This Agreement is intended to be for the exclusive benefit
of the parties hereto, and except as provided in Subparagraphs (a) and (b) of
this Paragraph 10, no third party shall have any rights hereunder.

         11. NON-DISCLOSURE; STATEMENTS TO THIRD PARTIES.

                  a. Except as otherwise provided in Paragraph 7, all provisions
of this Agreement and the circumstances giving rise hereto are and shall remain
confidential and shall not be disclosed to any person not a party hereto (other
than (i) Executive's spouse, if any, (ii) each party's attorney, financial
advisor and/or tax advisor to the extent necessary for such advisor



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to render appropriate legal, financial and tax advice, and (iii) persons or
entities that fall within the scope of Paragraphs 3 and 4 of this Agreement, but
only to the extent required thereby), except as necessary to carry out the
provisions of this Agreement, and except as may be required by law.
Notwithstanding the foregoing, this Agreement may be disclosed and described as
well as filed with or provided to the Securities and Exchange Commission or any
other governmental instrumentality or agency, including the Internal Revenue
Service, if either party deems such filing or provision to be necessary.

                  b. Because the purpose of this Agreement is to settle amicably
any and all potential disputes or claims among the parties, neither Executive
nor the Company shall, directly or indirectly, make or cause to be made any
statements to any third parties criticizing or disparaging the other or
commenting on the character or business reputation of the other. Executive
further hereby agrees not: (i) to comment to others concerning the status, plans
or prospects of the business of the Company, or (ii) to engage in any act or
omission that would be detrimental, financially or otherwise, to the Company, or
that would subject the Company to public disrespect, scandal, or ridicule. For
purposes of this Subparagraph 11.b., the "Company" shall mean the Company and
its present and former predecessors, subsidiaries, divisions, related or
affiliated companies, officers, directors, stockholders, members, employees,
heirs, successors, assigns, representatives, agents, accountants and counsel.

         12. NOTICES. For all purposes of this Agreement, all communications
provided for herein shall be in writing and shall be deemed to have been duly
given when delivered, addressed to the Company (to the attention of the Chief
Executive Officer) at its principal executive offices and to Executive at his
principal residence, 9915 Music Street, Novelty, Ohio 44065, or to such other
address as any party may have furnished to the other in writing and in
accordance herewith. Notices of change of address shall be effective only upon
receipt.

         13. MISCELLANEOUS. No provision of this Agreement may be modified,
waived or discharged unless such modification, waiver or discharge is agreed to
in writing signed by Executive and the Company. No waiver by either party hereto
at any time of any breach by the other party hereto or compliance with any
condition or provision of this Agreement to be performed by such other party
shall be deemed a waiver of similar or dissimilar provisions or conditions at
the same or at any prior or subsequent time. No agreements or representations,
oral or otherwise, expressed or implied with respect to the subject matter
hereof have been made by any of the parties that are not set forth expressly in
this Agreement and every one of them (if, in fact, there have been any) is
hereby terminated without liability or any other legal effect whatsoever.

         14. ENTIRE AGREEMENT. This Agreement shall constitute the entire
agreement among the parties hereto with respect to the subject matter hereof and
shall supersede all prior verbal or written agreements, covenants,
communications, understandings, commitments, representations or warranties,
whether oral or written, by any party hereto or any of its representatives
pertaining to such subject matter.

         15. GOVERNING LAW. Any dispute, controversy, or claim of whatever
nature arising out of or relating to this Agreement or breach thereof shall be
governed by and under the laws of the State of Ohio.



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         16. VALIDITY. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, which shall nevertheless remain in full force and
effect.

         17. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
together shall constitute one and the same Agreement.

         18. CAPTIONS AND PARAGRAPH HEADINGS. Captions and Paragraph headings
used herein are for convenience and are not part of this Agreement and shall not
be used in construing it.

         19. FURTHER ASSURANCES. Each party hereto shall execute such additional
documents, and do such additional things, as may reasonably be requested by the
other party to effectuate the purposes and provisions of this Agreement.




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                  IN WITNESS WHEREOF, the parties have executed and delivered
this Agreement as of the date first set forth above.

                                             GLIATECH INC.

                                             By: /s/ Robert P. Pinkas
                                                 -------------------------------
                                             Name:  Robert P. Pinkas
                                             Title:  Chairman


                                             Date: September 27, 2000
                                                 -------------------------------




Witness: /s/ Rodney E. Dausch                /s/  Michael A. Zupon
        ----------------------------         -----------------------------------

Date:  September 25, 2000                    Date  September 25, 2000
       -----------------------------              ------------------------------




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