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                                                                    EXHIBIT 10-C

                          REGISTRATION RIGHTS AGREEMENT


         This REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of May
9, 1997 is made and entered into between ZILA, INC., a Delaware corporation (the
"Company"), and DEERE PARK CAPITAL MANAGEMENT (the "Investor").

         WHEREAS, the Company and the Investor have entered into that certain
Private Equity Line of Credit Agreement, dated as of April 30, 1997 (the
"Investment Agreement"), pursuant to which the Company will issue, from time to
time, to the Investor shares of Common Stock, par value $.001 per share (the
"Common Stock");

         WHEREAS, pursuant to the terms of, and in partial consideration for,
the Investor's agreement to enter into the Investment Agreement, the Company has
issued to the Investor a Warrant of even date herewith, exercisable from time to
time during the period commencing October 31, 1997 and ending October 31, 2000
(the "Warrant") for the purchase of an aggregate of 285,000 shares of Common
Stock at a price specified in such Warrant;

         WHEREAS, pursuant to the terms of, and in partial consideration for,
the Investor's agreement to enter into the Investment Agreement, the Company has
agreed to provide the Investor with certain registration rights with respect to
the Registrable Securities (as defined below);

         NOW, THEREFORE, in consideration of the premises, the representations,
warranties, covenants and agreements contained herein, in the Warrant and in the
Investment Agreement, and for other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, intending to be legally bound
hereby, the parties hereto agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

         Section 1.1. Definitions. Capitalized terms defined in the Investment
Agreement or the Warrant shall have the same meanings herein as are ascribed to
them therein. In addition, the following terms shall have the meanings ascribed
below:

                  "Registrable Securities" means all of the Common Stock and any
other securities issued or issuable upon exercise of the Warrants as provided
therein until (i) a registration statement under the Act covering the offering
of such securities has been declared effective by the SEC and such securities
have been disposed of pursuant to such effective registration statement, (ii)
such securities are sold under circumstances in which all of the applicable
conditions of Rule 144 (or any similar provision then in force) under the Act
("Rule 144") are met, (iii) such securities have been otherwise transferred and
the Company has delivered a new certificate or other evidence of ownership for
such securities not bearing a restrictive legend or (iv) such time as, in the
opinion of counsel to the Company, which counsel shall be reasonably acceptable
to the Investor, such securities may be sold without any time,


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volume or manner limitation pursuant to Rule 144(k) (or any similar provision
then in effect) under the Act.

                  "Registration Statement"  See Section 2.1(a).

                                   ARTICLE II
                               REGISTRATION RIGHTS

         Section 2.1. Form S-3 Registration Statements.

                  (a) Filing of Form S-3 Registration Statements. Subject to the
terms and conditions of this Agreement and in accordance with the provisions of
Section 3.2(a) of the Investment Agreement, the Company shall file with the SEC
a registration statement on Form S-3 (the "Registration Statement") under the
Securities Act for the registration of the resale by the Investor of Common
Stock to be issued upon exercise of the Warrant.

                  (b) Effectiveness of Registration Statement. The Registration
Statement shall be declared effective by the SEC no later than August 30, 1997
and shall remain in effect until such time as no Registrable Securities remain
unsold.

                  (c) Penalties for Failure to Obtain or Maintain Effectiveness
of Registration Statement. In the event the Company fails to obtain the
effectiveness of a Registration Statement within the time period set forth in
Section 2.1(b), subject to extension as provided in Section 6.10 of the
Investment Agreement, the Company shall pay to the Investor the amounts set
forth in such Section 6.10.

                                   ARTICLE III
                             REGISTRATION PROCEDURES

         Section 3.1. Filings; Information. Whenever the Company is required to
effect or cause the registration of Registrable Securities pursuant to Section
2.1, the Company will use its best efforts to effect the registration of such
Registrable Securities in accordance with the intended method of disposition
thereof as quickly as practicable, and in connection with any such request:

                  (a) The Company will as expeditiously as possible, prepare and
file with the SEC a registration statement on Form S-3 and use its best efforts
to cause such filed Registration Statement to become and remain effective
(pursuant to Rule 415 under the Act or otherwise), and the Company will as
expeditiously as possible prepare and file with the SEC such amendments and
supplements to such Registration Statement and the prospectus used in connection
therewith as may be necessary to keep such Registration Statement effective for
the time periods prescribed by Section 2.1(b) and comply with the provisions of
the Act with respect to the disposition of all securities covered by such
Registration Statement during such period in accordance with the intended
methods of disposition by the Investor set forth in such Registration Statement.


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                  (b) The Company will, prior to filing a Registration Statement
or prospectus or any amendment or supplement thereto (excluding amendments
deemed to result from the filing of documents incorporated by reference
therein), furnish to the Investor and one firm of counsel representing the
Investor, copies of such Registration Statement as proposed to be filed,
together with exhibits thereto, which documents will be subject to review by
such parties, and thereafter furnish to the Investor and its counsel for their
review such number of copies of such Registration Statement, each amendment and
supplement thereto (in each case including all exhibits thereto), the prospectus
included in such Registration Statement (including each preliminary prospectus)
and such other documents or information as the Investor or counsel may
reasonably request in order to facilitate the disposition of the Registrable
Securities.

                  (c) After the filing of the Registration Statement, the
Company will promptly notify the Investor of any stop order issued or threatened
by the SEC in connection therewith and take all reasonable actions required to
prevent the entry of such stop order or to remove it if entered.

                  (d) The Company will use its best efforts to (i) register or
qualify such Registrable Securities under such other securities or blue sky laws
of such jurisdictions in the United States as the Investor may reasonably (in
light of its intended plan of distribution) request, and (ii) cause such
Registrable Securities to be registered with or approved by such other
governmental agencies or authorities in the United States as may be necessary by
virtue of the business and operations of the Company and do any and all other
acts and things that may be reasonably necessary or advisable to enable the
Investor to consummate the disposition of the Registrable Securities; provided
that the Company will not be required to (A) qualify generally to do business in
any jurisdiction where it would not otherwise be required to qualify but for
this paragraph (d), (B) subject itself to taxation in any such jurisdiction or
(C) consent or subject itself to general service of process in any such
jurisdiction.

                  (e) The Company will immediately notify the Investor upon the
occurrence of any of the following events in respect of a Registration Statement
or related prospectus in respect of an offering of Registrable Securities; (i)
receipt of any request for additional information by the SEC or any other
federal or state governmental authority during the period of effectiveness of
the Registration Statement for amendments or supplements to the Registration
Statement or related prospectus; (ii) the issuance by the SEC or any other
federal or state governmental authority of any stop order suspending the
effectiveness of the Registration Statement or the initiation of any proceedings
for that purpose; (iii) receipt of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose; (iv) the happening of any event
which makes any statement made in the Registration Statement or related
prospectus or any document incorporated or deemed to be incorporated therein by
reference untrue in any material respect or which requires the making of any
changes in the Registration Statement, related prospectus or documents so that,
in the case of the Registration Statement, it will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading, and
that in the case of the related prospectus, it will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading; and (vi) the Company's
reasonable determination that a post-effective amendment to the Registration


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Statement would be appropriate; and the Company will promptly make available to
the Investor any such supplement or amendment to the related prospectus.

                  (f) The Company will enter into customary agreements and take
such other actions as are reasonably required in order to expedite or facilitate
the disposition of such Registrable Securities (the Investor may, at its option,
require that any or all of the representations, warranties and covenants of the
Company also be made to and for the benefit of the Investor).

                  (g) The Company will make available to the Investor (and will
deliver to Investor's counsel), subject to restrictions imposed by the United
States federal government or any agency or instrumentality thereof, copies of
all correspondence between the SEC and the Company, its counsel or auditors and
will also make available for inspection by the Investor and any attorney,
accountant or other professional retained by the Investor (collectively, the
"Inspectors"), all financial and other records, pertinent corporate documents
and properties of the Company (collectively, the "Records") as shall be
reasonably necessary to enable them to exercise their due diligence
responsibility, and cause the Company's officers and employees to supply all
information reasonably requested by any Inspectors in connection with such
Registration Statement. Records which the Company determines, in good faith, to
be confidential and which it notifies the Inspectors are confidential shall not
be disclosed by the Inspectors unless (i) the disclosure of such Records is
necessary to avoid or correct a misstatement or omission in such Registration
Statement or (ii) the disclosure or release of such Records is requested or
required pursuant to oral questions, interrogatories, requests for information
or documents or a subpoena or other order from a court of competent jurisdiction
or other process; provided that prior to any disclosure or release pursuant to
clause (ii), the Inspectors shall provide the Company with prompt notice of any
such request or requirement so that the Company may seek an appropriate
protective order or waive such Inspectors' obligation not to disclose such
Records; and, provided further, that if failing the entry of a protective order
or the waiver by the Company permitting the disclosure or release of such
Records, the Inspectors, upon advice of counsel, are compelled to disclose such
Records, the Inspectors may disclose that portion of the Records which counsel
has advised the Inspectors that the Inspectors are compelled to disclose. The
Investor agrees that information obtained by it solely as a result of such
inspections (not including any information obtained from a third party who,
insofar as is known to the Investor after reasonable inquiry, is not prohibited
from providing such information by a contractual, legal or fiduciary obligation
to the Company) shall be deemed confidential and shall not be used by it as the
basis for any market transactions in the securities of the Company or its
Affiliates unless and until such information is made generally available to the
public. The Investor further agrees that it will, upon learning that disclosure
of such Records is sought in a court of competent jurisdiction, give notice to
the Company and allow the Company, at its expense, to undertake appropriate
action to prevent disclosure of the Records deemed confidential.

                  (h) The Company will furnish to the Investor a signed
counterpart, addressed to the Investor, of an opinion or opinions of counsel to
the Company in customary form and covering such matters of the type customarily
covered by opinions, as the Investor therefor reasonably requests.

                  (i) The Company will otherwise comply with all applicable
rules and regulations of the SEC, including, without limitation, compliance with
applicable reporting requirements under the Exchange Act.


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                  (j) The Company will appoint a transfer agent and registrar
for all such Registrable Securities covered by such Registration Statement not
later than the effective date of such Registration Statement.

                  The Company may require the Investor to promptly furnish in
writing to the Company such information regarding the distribution of the
Registrable Securities as the Company may from time to time reasonably request
and such other information as may be legally required in connection with such
registration including, without limitation, all such information as may be
requested by the SEC or the NASD. The Investor agrees to provide such
information requested in connection with such registration within ten (10)
business days after receiving such written request and the Company shall not be
responsible for (and the penalties specified in Section 2.1(c) shall not apply
in respect of) any delays in obtaining or maintaining the effectiveness of the
Registration Statement caused by the Investor's failure to timely provide such
information. The Investor agrees that, upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3.1(e)
hereof, the Investor will forthwith discontinue disposition of Registrable
Securities pursuant to the Registration Statement covering such Registrable
Securities until the Investor's receipt of the copies of the supplemented or
amended prospectus contemplated by Section 3.1(e) hereof, and, if so directed by
the Company, the Investor will deliver to the Company all copies, other than
permanent file copies then in the Investor's possession, of the most recent
prospectus covering such Registrable Securities at the time of receipt of such
notice. In the event the Company shall give such notice, the Company shall
extend the period during which such Registration Statement shall be maintained
effective (including the period referred to in Section 3.1(a) hereof) by the
number of days during the period from and including the date of the giving of
notice pursuant to Section 3.1(e) hereof to the date when the Company shall make
available to the Investor a prospectus supplemented or amended to conform with
the requirements of Section 3.1(e) hereof.

         Section 3.2. Registration Expenses. In connection with each
Registration Statement, the Company shall pay the following registration
expenses incurred in connection with the registration thereunder (the
"Registration Expenses"): (i) all registration and filing fees, (ii) fees and
expenses of compliance with securities or blue sky laws (including reasonable
fees and disbursements of counsel in connection with blue sky qualifications of
the Registrable Securities), (iii) printing expenses, (iv) the Company's
internal expenses (including, without limitation, all salaries and expenses of
its officers and employees performing legal or accounting duties), (v) the fees
and expenses incurred in connection with the listing of the Registrable
Securities, (vi) reasonable fees and disbursements of counsel for the Company
and customary fees and expenses, if any, for independent certified public
accountants retained by the Company, and (vii) the fees and expenses of any
special experts retained by the Company in connection with such registration.
The Company shall have no obligation to pay any underwriting fees, discounts or
commissions attributable to the sale of Registrable Securities or any legal fees
or expenses of counsel to the Investors or the Investor Agent, such costs to be
borne by the Investors.


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                                   ARTICLE IV
                        INDEMNIFICATION AND CONTRIBUTION

         Section 4.1 Indemnification.

         (a) Indemnification of Investor. The Company agrees to indemnify and
hold harmless the Investor and each person, if any, who controls the Investor
within the meaning of Section 15 of the Securities Act or Section 20 of the
Exchange Act as follows:

             (i)   against any and all loss, liability, claim, damage and 
expense whatsoever, as incurred, arising out of any untrue statement of a
material fact contained in the Registration Statement (or any amendment
thereto), including any prospectus, or in any offering circular or other
document, as applicable, or the omission or alleged omission therefrom of a
material fact required to be stated therein or necessary to make the statement
therein not misleading or arising out of any untrue statement or alleged untrue
statement of a material fact contained in any prospectus (or any amendment or
supplement thereto), or in any offering circular or other document, as
applicable, or the omission or alleged omission therefrom of a material fact
necessary in order to make the statements therein, in the light of the
circumstances under which they were made, not misleading;

             (ii)  against any and all loss, liability, claim, damage and 
expense whatsoever, as incurred, to the extent of the aggregate amount paid in
settlement of any litigation, or any investigation or proceeding by any
governmental agency or body, commenced or threatened, or any claim whatsoever
based upon any such statement or omission, or any such alleged untrue statement
or omission; provided that (subject to Section 4.1(d) below) any such settlement
is effected with the written consent of the Company; and

             (iii) against any and all expenses whatsoever, as incurred 
(including the fees and disbursements of one counsel chosen by the Investor
Agent who shall represent all Investors under the Investment Agreement),
reasonably incurred in investigating, preparing or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or any claim whatsoever based upon any such
untrue statement or omission, or any such alleged untrue statement or omission,
to the extent that any such expense is not paid under (i ) or (ii) above;
provided, however, that this indemnity shall not apply to any loss, liability,
claim, damage or expense to the extent arising out of any untrue statement or
omission or alleged untrue statement or omission made in reliance upon and in
conformity with written information furnished to the Company by the Investor
expressly for use in the Registration Statement (or any amendment thereto),
including any prospectus (or any amendment or supplement thereto), or in any
offering circular or other document, as applicable.

         (b) Indemnification of Company. The Investor agrees to indemnify and
hold harmless the Company, its directors, each of its officers who signed the
Registration Statement, and each person, if any, who controls the Company within
the meaning of Section 15 of the Securities Act or Section 20 of the Exchange
Act against any and all loss, liability, claim, damage and expense (i) described
in the indemnity contained in subsection (a) of this Section, as incurred, but
only with respect to untrue statements or omissions, or alleged untrue
statements or omissions, made in the Registration Statement


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(or any amendment thereto), including any prospectus (or any amendment or
supplement thereto), or offering circular or other document, as applicable, in
reliance upon and in conformity with written information furnished to the
Company by the Investor expressly for use in the Registration Statement (or any
amendment or supplement thereto) or in any offering circular or other document,
as applicable and (ii) arising as a result of the Investor's failure to comply
with any prospectus delivery requirements in connection with the resale of
Registrable Securities.

         (c) Action against Parties; Notification. Each indemnified party shall
give notice as promptly as reasonably practicable to each indemnifying party of
any action commenced against it in respect of which indemnity may be sought
hereunder, but failure to so notify an indemnifying party shall not relieve such
indemnifying party from any liability hereunder to the extent it is not
materially prejudiced as a result thereof and in any event shall not relieve it
from any liability which it may have otherwise than on account of his indemnity
agreement. In the case of parties indemnified pursuant to Section 4.1(a) above,
counsel to the indemnified parties shall be selected by the Investor, and in the
case of parties indemnified pursuant to Section 4.1(b) above, counsel to the
indemnified parties shall be selected by the Company. An indemnifying party may
participate at its own expense in the defense of any such action; provided,
however, that counsel to the indemnifying party shall not (except with the
consent of the indemnified party) also be counsel to the indemnified party. In
no event shall the indemnifying parties be liable for fees and expenses of more
than one counsel (in addition to any local counsel) separate from their own
counsel for all indemnifies parties in connection with any one action or
separate but similar or related actions in the same jurisdiction arising out of
the same general allegations or circumstances. No indemnifying party shall,
without the prior written consent of the indemnified parties, settle or
compromise or consent to the entry or any judgment with respect to any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or any claim whatsoever in respect of which
indemnification or contribution could be sought under this Section or Section
4.2 hereof (whether or not the indemnified parties are actual or potential
parties thereto), unless such settlement, compromise or consent (i) includes an
unconditional release of each indemnified party from all liability arising out
of such litigation , investigation proceeding or claim and (ii) does not include
a statement as to or an admission of fault, culpability or a failure to act by
or on behalf of an any indemnified party.

         (d) Settlement without Consent if Failure to Reimburse. If at any time
an indemnified party shall have requested an indemnifying party to reimburse the
indemnified party for the fees and expenses of counsel, such indemnifying party
agrees that it shall be liable for any settlement of the nature contemplated by
Section 4.1(a)(ii) effected without its written consent if (i) such settlement
is entered into more than 45 days after receipt by such indemnifying party of
the aforesaid request, (ii) such indemnifying party shall have received notice
of the terms of such settlement at least 30 days prior to such settlement being
entered into and (iii) such indemnifying party shall not have reimbursed such
indemnified party in accordance with such request prior to the date of such
settlement.

         Section 4.2 Contribution. If the indemnification provided for in
Section 4.1 hereof is for any reason unavailable to or insufficient to hold
harmless an indemnified party in respect of any losses, liabilities, claims,
damages or expenses referred to herein, then each indemnifying party shall
contribute to the aggregate amount of such losses, liabilities, claims, damages
and expenses incurred by such indemnified party, as incurred (i) in such
proportion as is appropriate to reflect the relative


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benefits received by the Company on the one hand and the Investor on the other
hand from the offering of the Common Stock pursuant to this Agreement or (ii) if
the allocation provided by clause (i) is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause (i) above but also the relative fault of the Company on
the one hand and of the Investor on the other hand in connection with the
statements or omissions which resulted in such losses, liabilities, claims,
damages or expenses, as well as any other relevant equitable considerations.

         The relative benefits received by the Company on the one hand and the
Investor on the other hand in connection with the offering of the Common Stock
pursuant to this Agreement shall be deemed to be in the same respective
proportions as the total net proceeds from the offering of the Common Stock
pursuant to the Investment Agreement (before deducting expenses) received by the
Company and the total net proceeds received by the Investor (before deducting
expenses) bear to the aggregate public offering price.

         The relative fault of the Company on the one hand and the Investor on
the other hand shall be determined by reference to, among other things, whether
any such untrue or alleged untrue statement of a material fact or omission or
alleged omission to state a material fact relates to information supplied by the
Company or by the Investor and the parties' relative intent, knowledge, access
to information and opportunity to correct or prevent such statement or omission.

         The Company and the Investors agree that it would not be just and
equitable if contribution pursuant to this Section 4.2 were determined on a
pro-rata allocation or by any other method of allocation which does not take
account of the equitable considerations referred to above in this Section 4.2.
The aggregate amount of losses, liabilities, claims, damages and expenses
incurred by an indemnified party and referred to above in this Section 4.2 shall
be deemed to include any legal or other expenses reasonably incurred by such
indemnified party in investigating, preparing or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or any claim whatsoever based upon any such
untrue or alleged untrue statement or omission or alleged omission.

         Notwithstanding the provisions of this Section 4.2, the Investor shall
not be required to contribute any amount in excess of the amount by which the
total price at which the Common Stock purchased by it and resold to the public
exceeds the amount of any damages which the Investor has otherwise been required
to pay by reason of any such untrue or alleged untrue statement or omission or
alleged omission.

         No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the Securities Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation.

         For purposes of this Section 4.2, each person, if any, who controls the
Investor within the meaning of Section 15 of the Securities Act or Section 20 of
the Exchange Act shall have the same rights to contribution as such Investor,
and each director of the Company, each officer of the Company who signed the
Registration Statement, and each person, if any, who controls the Company within
the


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meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act
shall have the same rights to contribution as the Company.

                                    ARTICLE V
                                  MISCELLANEOUS

         Section 5.1. Term. The registration rights provided to the holders of
Registrable Securities hereunder shall terminate at such time as no Registrable
Securities are outstanding; provided, however, that the provisions of Article IV
hereof shall survive any termination of this Agreement.

         Section 5.2. Rule 144. The Company covenants that it will file all
reports required to be filed by it under the Act and the Exchange Act and that
it will take such further action as holders of Registrable Securities may
reasonably request, all to the extent required from time to time to enable the
Investor to sell Registrable Securities without registration under the Act
within the limitation of the exemptions provided by (a) Rule 144, as such Rule
may be amended from time to time, or (b) any successor or similar rule or
regulation hereafter adopted by the SEC. If at any time the Company is not
required to file such reports, it will, upon the request of any holder of
Registrable Securities, make publicly available other information so long as
necessary to permit sales pursuant to Rule 144. Upon the request of the
Investor, the Company will deliver to the Investor a written statement as to
whether it has complied with such requirements.

         Section 5.3. Amendment and Modification. Any provision of this
Agreement may be waived, provided that such waiver is set forth in a writing
executed by the party against whom the enforcement of such waiver is sought. The
provisions of this Agreement, including the provisions of this sentence, may not
be amended, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, unless the Company has obtained the
written consent of the holders of a majority of the then outstanding Registrable
Securities. Notwithstanding the foregoing, the waiver of any provision hereof
with respect to a matter that relates exclusively to the rights of holders of
Registrable Securities whose securities are being sold pursuant to a
Registration Statement and does not directly or indirectly affect the rights of
other holders of Registrable Securities may be given by holders of at least a
majority of the Registrable Securities being sold by such holders; provided that
the provisions of this sentence may not be amended, modified or supplemented
except in accordance with the provisions of the immediately preceding sentence.
No course of dealing between or among any Persons having any interest in this
Agreement will be deemed effective to modify, amend or discharge any part of
this Agreement or any rights or obligations of any person under or by reason of
this Agreement.

         Section 5.4. Successors and Assigns; Entire Agreement. This Agreement
and all of the provisions hereof shall be binding upon and inure to the benefit
of the parties hereto and their respective successors and assigns. The Investor
may assign its rights under this Agreement to any subsequent holder of Warrants
or Registrable Securities, provided that the Company shall have the right to
require any holder of Registrable Securities to execute a counterpart of this
Agreement as a condition to such holder's claim to any rights hereunder. This
Agreement, together with the Investment Agreement and the Warrants, set forth
the entire agreement and understanding between the parties as


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to the subject matter hereof and merges and supersedes all prior discussions,
agreements and understandings of any and every nature among them.

         Section 5.5. Separability. In the event that any provision of this
Agreement or the application of any provision hereof is declared to be illegal,
invalid or otherwise unenforceable by a court of competent jurisdiction, the
remainder of this Agreement shall not be affected except to the extent necessary
to delete such illegal, invalid or unenforceable provision unless that provision
held invalid shall substantially impair the benefits of the remaining portions
of this Agreement.

         Section 5.6. Notices. All notices, demands, requests, consents,
approvals or other communications required or permitted to be given hereunder or
which are given with respect to this Agreement shall be in writing and shall be
personally served or deposited in the mail, registered or certified, return
receipt requested, postage prepaid, or delivered by reputable air courier
service with charges prepaid, or transmitted by hand delivery, telegram, telex
or facsimile, addressed as set forth below, or to such other address as such
party shall have specified most recently by written notice: (i) if to the
Company, to: Zila, Inc., 5227 North 7th Street, Phoenix, AZ 85014-2800;
Attention: Mr. Joseph Hines, Facsimile No.: (602) 234-2318, with copies (which
shall not constitute notice) to: Squire, Sanders & Dempsey L.L.P., 40 N. Central
Ave., Phoenix, AZ 85004, Attention: Christopher D. Johnson, Facsimile No.:
(602)253-8129; H.J. Meyers & Company, Inc., 180 Maiden Lane, New York, New York
10038, Attention: Tom Parigian, Facsimile No.: (212)248-4241; and (ii) if to the
Investors, to Deere Park Capital Management, 650 Dundee Road, Suite 460,
Northbrook, Illinois 60062, Attention: Douglas A. Gerrard, Facsimile No.: (847)
509-8529 and Bartholomew Investment, L.P., 1 Sioux Court, Justice, IL 60458,
Facsimile No.: (847)509-8529, with copies (which shall not constitute notice) to
Ungaretti & Harris, 3500 Three First National Plaza, Chicago, IL 60602;
Attention: Gary I. Levenstein, Esq., Facsimile No.: (312)977-4108. Notice shall
be deemed given on the date of service or transmission if personally served or
transmitted by telegram, telex or facsimile. Notice otherwise sent as provided
herein shall be deemed given on the third business day following the date mailed
or on the second business day following delivery of such notice by a reputable
air courier service.

         Section 5.7. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAW OF THE STATE OF ILLINOIS, WITHOUT
GIVING EFFECT TO PRINCIPLES OF CONFLICTS OF LAWS THEREOF.

         Section 5.8. Headings. The headings in this Agreement are for
convenience of reference only and shall not constitute a part of this Agreement,
nor shall they affect their meaning, construction or effect.

         Section 5.9. Counterparts. This Agreement may be executed in multiple
counterparts, each of which shall be deemed to be an original instrument and all
of which together shall constitute one and the same instrument.


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         Section 5.10. Further Assurances. Each party shall cooperate and take
such action as may be reasonably requested by another party in order to carry
out the provisions and purposes of this Agreement and the transactions
contemplated hereby.

         Section 5.11. Remedies. In the event of a breach or a threatened breach
by any party to this Agreement of its obligations under this Agreement, any
party injured or to be injured by such breach will be entitled to specific
performance of its rights under this Agreement or to injunctive relief, in
addition to being entitled to exercise all rights provided in this Agreement and
granted by law. The parties agree that the provisions of this Agreement shall be
specifically enforceable, it being agreed by the parties that the remedy at law,
including monetary damages, for breach of any such provision will be inadequate
compensation for any loss and that any defense or objection in any action for
specific performance or injunctive relief that a remedy at law would be adequate
is waived.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by the undersigned, thereunto duly authorized, as of the date first set
forth above.

                                        ZILA, INC.


                                        By: ________________________________
                                            Name: __________________________
                                            Title: _________________________


                                        DEERE PARK CAPITAL MANAGEMENT



                                        By: ________________________________
                                            Name: __________________________
                                            Title: _________________________


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