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                                                                    Exhibit 10.0


                          REGISTRATION RIGHTS AGREEMENT


         REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of October
17, 1997, by and among Zila, Inc., a Delaware corporation, with headquarters
located at 5227 North Seventh Street, Phoenix, Arizona 85014-2800 (the
"COMPANY"), and the undersigned buyers (each, a "BUYER" and collectively, the
"BUYERS").

         WHEREAS:

         A. In connection with the Securities Purchase Agreement by and among
the parties of even date herewith (the "SECURITIES PURCHASE AGREEMENT"), the
Company has agreed, upon the terms and subject to the conditions contained
herein, to (i) issue and sell to the Buyers shares of the Company's Series A
Redeemable Convertible Preferred Stock (the "PREFERRED SHARES"), which will be
convertible into shares of the Company's common stock, par value $.001 per share
(the "COMMON STOCK") (as converted, the "CONVERSION SHARES"), in accordance with
the terms of the Company's Certificate of Designations, Preferences and Rights
of the Series A Redeemable Convertible Preferred Stock (the "CERTIFICATE OF
DESIGNATIONS"), and (ii) issue Warrants (the "WARRANTS") to acquire Common Stock
(the "WARRANT SHARES"); and

         B. To induce the Buyers to execute and deliver the Securities Purchase
Agreement, the Company has agreed to provide certain registration rights under
the Securities Act of 1933, as amended, and the rules and regulations
thereunder, or any similar successor statute (collectively, the "1933 ACT"), and
applicable state securities laws:

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and the
Buyers hereby agree as follows:

         1.       DEFINITIONS.

                  As used in this Agreement, the following terms shall have the
following meanings:

                  a. "INVESTOR" means a Buyer and any transferee or assignee
thereof to whom a Buyer assigns its rights under this Agreement and who agrees
to become bound by the provisions of this Agreement in accordance with Section
9.

                  b. "PERSON" means a corporation, a limited liability company,
an association, a partnership, an organization, a business, an individual, a
governmental or political subdivision thereof or a governmental agency.
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                  c. "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing one or more Registration
Statements in compliance with the 1933 Act and pursuant to Rule 415 under the
1933 Act or any successor rule providing for offering securities on a continuous
basis ("RULE 415"), and the declaration or ordering of effectiveness of such
Registration Statement(s) by the United States Securities and Exchange
Commission (the "SEC").

                  d. "REGISTRABLE SECURITIES" means the Conversion Shares
(including any Repricing Shares issuable in accordance with the Certificate of
Designations) and the Warrant Shares issued or issuable upon conversion of the
Preferred Shares and exercise of the Warrants, respectively, and any shares of
capital stock issued or issuable with respect to the Conversion Shares, the
Warrant Shares, the Warrants or the Preferred Shares as a result of any stock
split, stock dividend, recapitalization, exchange or similar event or otherwise.

                  e. "REGISTRATION STATEMENT" means a registration statement of
the Company filed under the 1933 Act.

Capitalized terms used herein and not otherwise defined herein shall have the
respective meanings set forth in the Securities Purchase Agreement.

         2.       REGISTRATION.

                  a. Mandatory Registration. The Company shall prepare, and, on
or prior to 90 days after the date of issuance of the relevant Preferred Shares,
file with the SEC a Registration Statement or Registration Statements (as is
necessary) on Form S-3 (or, if such form is unavailable for such a registration,
on such other form as is available for such a registration, subject to the
consent of the Investors holding a majority of the Registrable Securities and
the provisions of Section 2(c), which consent will not be unreasonably
withheld), covering the resale of all of the Registrable Securities, which
Registration Statement(s) to the extent allowable under the 1933 Act and the
Rules promulgated thereunder (including Rule 416) shall state that such
Registration Statement(s) also covers such indeterminate number of additional
shares of Common Stock as may become issuable upon conversion of the Preferred
Shares or exercise of the Warrants (i) to prevent dilution resulting from stock
splits, stock dividends or similar transactions and (ii) to account for any
obligation to issue Repricing Shares in accordance with the Certificate of
Designations. Such Registration Statement shall initially register for resale at
least 7,000,000 shares of Common Stock, subject to adjustment as provided in
Section 3(b). Such registered shares of Common Stock shall be allocated among
the Investors as set forth in Section 11(k) hereof. The Company shall use its
best efforts to have the Registration Statement(s) declared effective by the SEC
as soon as practicable, but in no event later than 120 days after the issuance
of the relevant Preferred Shares.

                  b. Counsel and Investment Bankers. Subject to Section 5
hereof, in connection with any offering pursuant to Section 2, the Buyers shall
have the right to select one 


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legal counsel and an investment banker or bankers and manager or managers to
administer their interest in the offering, which investment banker or bankers or
manager or managers shall be reasonably satisfactory to the Company. The Company
shall reasonably cooperate with any such counsel and investment bankers.

                  c. Payments by the Company. If (i) the Registration
Statement(s) covering the Registrable Securities required to be filed by the
Company pursuant to Section 2(a) hereof is not declared effective by the SEC on
or before the time specified in Section 2(a) hereof (the "REGISTRATION
DEADLINE") or if, after the Registration Statement has been declared effective
by the SEC, sales of the Registrable Securities (including any Registrable
Securities required to be registered pursuant to this Section 2(c) or Section
3(b) hereof) cannot be made pursuant to the Registration Statement (by reason of
a stop order or the Company's failure to update the Registration Statement or
any other reason outside the control of the Investors) or (ii) the Common Stock
is not listed or included for quotation on the New York Stock Exchange (the
"NYSE"), the Nasdaq National Market ("NASDAQ NM") or the Nasdaq SmallCap Market
("NASDAQ SMALLCAP") or the American Stock Exchange (the "AMEX") at any time
after the Registration Deadline, then the Company will make payments to the
Investors in such amounts and at such times as shall be determined pursuant to
this Section 2(c) as partial relief for the damages to the Investors by reason
of any such delay in or reduction of their ability to sell the Registrable
Securities (which remedy shall not be exclusive of any other remedies available
at law or in equity). The Company shall pay to each Investor an amount equal to
the product of (i) the aggregate purchase price of the Preferred Shares and
Warrants held by such Investor (including, without limitation, Preferred Shares
that have been converted into Conversion Shares and Warrants that have been
exercised for Warrant Shares then held by such Investor) (the "AGGREGATE SHARE
PRICE") multiplied by (ii) two hundredths (.02) multiplied by (iii) the sum of:
(y) the number of months (prorated for partial months) after the Registration
Deadline and prior to the date the Registration Statement filed pursuant to
Section 2(a) is declared effective by the SEC and (z) the number of months
(prorated for partial months) that sales of any Registrable Securities cannot be
made pursuant to the Registration Statement after the Registration Statement has
been declared effective or the Common Stock is not listed or included for
quotation on the NYSE, Nasdaq NM, Nasdaq SmallCap or AMEX; provided, however,
that there shall be excluded from each such period any delays which are solely
attributable to changes (other than corrections of Company mistakes with respect
to information previously provided by the Investors) required by the Investors
in the Registration Statement with respect to information relating to the
Investors, including, without limitation, changes to the plan of distribution.
(For example, if the Registration Statement is not effective by the Registration
Deadline, the Company would pay $20,000 per month for each $1,000,000 of
Aggregate Share Price until the Registration Statement becomes effective.) Such
amounts shall be paid in cash or, at the Company's option, may be convertible
into Common Stock at the "CONVERSION PRICE" (as defined in the Certificate of
Designations) then in effect. Any shares of Common Stock issued upon conversion
of such amounts shall be Registrable Securities. If the Company desires to
convert the amounts due hereunder into Registrable Securities it shall so notify
the Investors in writing within two (2) business days of the day on which such
amounts are first payable in cash and such amounts shall be so convertible
(pursuant to the mechanics set forth in the Certificate of 

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Designations), beginning on the last day upon which the cash amount would
otherwise be due in accordance with the following sentence. Payments of cash
pursuant hereto shall be made within five (5) days after the end of each period
that gives rise to such obligation, provided that, if any such period extends
for more than thirty (30) days, interim payments shall be made for each such
thirty (30) day period.

                  d. Piggy-Back Registrations. If at any time prior to the
expiration of the Registration Period (as hereinafter defined) a Registration
Statement is not in effect with respect to the Registrable Securities and the
Company proposes to file with the SEC a Registration Statement relating to an
offering for its own account or the account of others under the 1933 Act of any
of its securities (other than on Form S-4 or Form S-8 or their then equivalents
relating to securities to be issued solely in connection with any acquisition of
any entity or business or equity securities issuable in connection with stock
option or other employee benefit plans) the Company shall promptly send to each
Investor who is entitled to registration rights under this Section 2(d) written
notice of the Company's intention to file a Registration Statement and of such
Investor's rights under this Section 2(d) and, if within twenty (20) days after
receipt of such notice, such Investor shall so request in writing, the Company
shall include in such Registration Statement all or any part of the Registrable
Securities such Investor requests to be registered, subject to the priorities
set forth in Section 2(e) below. No right to registration of Registrable
Securities under this Section 2(d) shall be construed to limit any registration
required under Section 2(a). The obligations of the Company under this Section
2(d) may be waived by Investors holding a majority of the Registrable
Securities. If an offering in connection with which an Investor is entitled to
registration under this Section 2(d) is an underwritten offering, then each
Investor whose Registrable Securities are included in such Registration
Statement shall, unless otherwise agreed by the Company, offer and sell such
Registrable Securities in an underwritten offering using the same underwriter or
underwriters and, subject to the provisions of this Agreement, on the same terms
and conditions as other shares of Common Stock included in such underwritten
offering.

                  e. Priority in Piggy-Back Registration Rights in connection
with Registrations for Company Account. If the registration referred to in
Section 2(d) is to be an underwritten public offering and the managing
underwriter(s) advise the Company in writing, that in their reasonable good
faith opinion, marketing or other factors dictate that a limitation on the
number of shares of Common Stock which may be included in the Registration
Statement is necessary to facilitate and not adversely affect the proposed
offering, then the Company shall include in such registration: (1) first, all
securities the Company proposes to sell for its own account, (2) second, up to
the full number of securities proposed to be registered for the account of the
holders of securities entitled to inclusion of their securities in the
Registration Statement by reason of demand registration rights, and (3) third,
the securities requested to be registered by the Investors and other holders of
securities entitled to participate in the registration, as of the date hereof,
drawn from them pro rata based on the number each has requested to be included
in such registration.


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                  f. Eligibility for Form S-3. The Company represents, warrants
and covenants that on and after the date hereof it meets and will meet the
requirements for the use of Form S-3 for registration of the sale by the
Investors of the Registrable Securities and the Company has filed and shall file
all reports required to be filed by the Company with the SEC in a timely manner
so as to obtain and maintain such eligibility for the use of Form S-3. In the
event that Form S-3 is not available for sale by the Investors of the
Registrable Securities, then the Company (i) with the consent of the Investors
holding a majority of the Registrable Securities pursuant to Section 2(a), shall
register the sale of the Registrable Securities on another appropriate form and
(ii) the Company shall undertake to register the Registrable Securities on Form
S-3 as soon as such form is available, provided that the Company shall maintain
the effectiveness of the Registration Statement then in effect until such time
as a Registration Statement on Form S-3 covering the Registrable Securities has
been declared effective by the SEC.

                  g. Rule 416. The Company and the Investors each acknowledge
that an indeterminate number of Registrable Securities shall be registered
pursuant to Rule 416 under the Securities Act so as to include in such
Registration Statement any and all Registrable Securities which may become
issuable (i) to prevent dilution resulting from stock splits, stock dividends or
similar transactions and (ii) to account for any obligation to issue Repricing
Shares in accordance with the Certificate of Designations (collectively, the
"RULE 416 SECURITIES"). In this regard, the Company agrees to take all steps
necessary to ensure that all Registrable Securities are registered pursuant to
Rule 416 under the Securities Act in the Registration Statement and, absent
guidance from the SEC or other definitive authority to the contrary, the Company
shall affirmatively support and not take any action adverse to the position that
the Registration Statements filed hereunder cover all of the Rule 416
Securities. If the Company determines that the Registration Statements filed
hereunder do not cover all of the Rule 416 Securities, the Company shall
immediately provide to each Investor written notice (a "RULE 416 NOTICE")
setting forth the basis for the Company's position and the authority therefor.

         3.       RELATED OBLIGATIONS.

         Whenever an Investor has requested that any Registrable Securities be
registered pursuant to Section 2(c) or at such time as the Company is obligated
to file a Registration Statement with the SEC pursuant to Section 2(a), the
Company will use its best efforts to effect the registration of the Registrable
Securities in accordance with the intended method of disposition thereof and,
pursuant thereto, the Company shall have the following obligations:

                  a. The Company shall promptly prepare and file with the SEC a
Registration Statement with respect to the Registrable Securities (on or prior
to the 90th day after the date of issuance of any Preferred Shares for the
registration of Registrable Securities pursuant to Section 2(a)) and use its
best efforts to cause such Registration Statement relating to the Registrable
Securities to become effective as soon as possible after such filing (but in no
event later than 120 days after the issuance of any Preferred Shares for the
registration of Registrable Securities pursuant to Section 2(a)), and keep such
Registration Statement effective pursuant to Rule 415 at 


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all times until the earlier of (i) the date as of which the Investors may sell
all of the Registrable Securities without restriction pursuant to Rule 144(k)
promulgated under the 1933 Act (or successor thereto) or (ii) the date on which
(A) the Investors shall have sold all the Registrable Securities and (B) none of
the Preferred Shares or Warrants is outstanding, but in any event for a minimum
of three years from the date of issuance of the Preferred Shares (the
"REGISTRATION PERIOD"), which Registration Statement (including any amendments
or supplements thereto and prospectuses contained therein) shall not contain any
untrue statement of a material fact or omit to state a material fact required to
be stated therein, or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading.

                  b. The Company shall prepare and file with the SEC such
amendments (including post-effective amendments) and supplements to a
Registration Statement and the prospectus used in connection with such
Registration Statement, which prospectus is to be filed pursuant to Rule 424
promulgated under the 1933 Act, as may be necessary to keep such Registration
Statement effective at all times during the Registration Period, and, during
such period, comply with the provisions of the 1933 Act with respect to the
disposition of all Registrable Securities of the Company covered by such
Registration Statement until such time as all of such Registrable Securities
shall have been disposed of in accordance with the intended methods of
disposition by the seller or sellers thereof as set forth in such Registration
Statement. In the event (i) the Company delivers a Rule 416 Notice to the
Investors or the Investors who hold a majority in interest of the Registrable
Securities shall reasonably determine or the SEC shall state formally or
informally that Rule 416 under the Securities Act does not permit a registration
statement to cover securities which may become issuable upon conversion or
exercise of convertible or exercisable securities by reason of reductions in the
conversion or exercise price of such securities and (ii) the number of shares
available under a Registration Statement filed pursuant to this Agreement is,
for any three (3) consecutive trading days (the last of such three (3) trading
days being the "REGISTRATION TRIGGER DATE"), insufficient to cover one hundred
thirty five percent (135%) of the Registrable Securities issued or issuable upon
a conversion (without giving effect to any limitations on conversion contained
in Section 2(k) of the Certificate of Designations) of the Preferred Stock and
exercise of the Warrants, the Company shall amend the Registration Statement, or
file a new Registration Statement (on the short form available therefor, if
applicable), or both, so as to cover two hundred percent (200%) of the
Registrable Securities issued or issuable (without giving effect to any
limitations on conversion contained in Section 2(k) of the Certificate of
Designations) as of the Registration Trigger Date, in each case, as soon as
practicable, but in any event within fifteen (15) days after the Registration
Trigger Date (based on the market price then in effect of the Common Stock and
other relevant factors on which the Company reasonably elects to rely). The
Company shall cause such amendment and/or new Registration Statement to become
effective as soon as practicable following the filing thereof. In the event the
Company fails to obtain the effectiveness of any such Registration Statement
within sixty (60) days after a Registration Trigger Date, each Investor shall
thereafter have the option, exercisable in whole or in part at any time and from
time to time by delivery of a written notice to the Company (a "REDEMPTION
NOTICE"), to require the Company to purchase for cash, at an amount per share
equal to the Redemption Price (as defined in the Certificate of Designations), a
portion of the Investor's Preferred Shares such that the total number of


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Registrable Securities included on the Registration Statement for resale by such
Investor exceeds 135% of the Registrable Securities issued or issuable upon
conversion (without giving effect to any limitations on conversion contained in
Section 2(k) of the Certificate of Designation) of such Investor's Preferred
Shares and exercise of such Investor's Warrants. If the Company fails to redeem
any of such shares within five (5) business days after its receipt of a
Redemption Notice, then such Investor shall be entitled to the remedies provided
in the Certificate of Designations. For purposes of the calculation set forth in
the foregoing sentence, any restrictions on the convertibility of the Preferred
Shares or exerciseability of the Warrants shall be disregarded and such
calculation shall assume that the Preferred Shares and the Warrants are then
convertible and exercisable, respectively, into shares of Common Stock at the
then prevailing Conversion Rate (as defined in the Company's Certificate of
Designations) and Warrant Exercise Price (as defined in the Warrant),
respectively, if applicable.

                  c. The Company shall furnish to each Investor whose
Registrable Securities are included in any Registration Statement and its legal
counsel without charge (i) promptly after the same is prepared and filed with
the SEC at least one copy of such Registration Statement and any amendment(s)
thereto, including financial statements and schedules, all documents
incorporated therein by reference and all exhibits, the prospectus included in
such Registration Statement (including each preliminary prospectus) and, with
regards to such Registration Statement(s), any correspondence by or on behalf of
the Company to the SEC or the staff of the SEC and any correspondence from the
SEC or the staff of the SEC to the Company or its representatives, (ii) upon the
effectiveness of any Registration Statement, (or any amendments thereto) a
notice stating that such Registration Statement or any amendment thereto has
been declared effective and (iii) such number of copies of the prospectus
included in such Registration Statement and all amendments and supplements
thereto (or such other number of copies as such Investor may reasonably request)
and such other documents, including any preliminary prospectus, as such Investor
may reasonably request in order to facilitate the disposition of the Registrable
Securities owned by such Investor.

                  d. The Company shall use reasonable efforts to (i) register
and qualify the Registrable Securities covered by a Registration Statement under
such other securities or "blue sky" laws of such jurisdictions in the United
States as any Investor reasonably requests, (ii) prepare and file in those
jurisdictions, such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; provided, however, that
the Company shall not be required in connection therewith or as a condition
thereto to (x) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(d), (y) subject itself
to general taxation in any such jurisdiction, or (z) file a general consent to
service of process in any such jurisdiction. The Company shall promptly notify
each Investor who holds Registrable Securities of the receipt by the Company of
any notification with respect to the suspension of the registration or
qualification of any of the Registrable Securities 


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for sale under the securities or "blue sky" laws of any jurisdiction in the
United States or its receipt of actual notice of the initiation or threatening
of any proceeding for such purpose.

                  e. As promptly as practicable after becoming aware of such
event, the Company shall notify each Investor in writing of the happening of any
event as a result of which the prospectus included in a Registration Statement,
as then in effect, includes an untrue statement of a material fact or omission
to state a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading, and promptly prepare a supplement or amendment to such
Registration Statement to correct such untrue statement or omission, and deliver
ten (10) copies of such supplement or amendment to each Investor (or such other
number of copies as such Investor may reasonably request). The Company shall
also promptly notify each Investor in writing (i) when a prospectus or any
prospectus supplement or post-effective amendment has been filed, and when a
Registration Statement or any post-effective amendment has become effective
(notification of such effectiveness shall be delivered to each Investor by
facsimile on the same day of such effectiveness and by overnight mail), (ii) of
any request by the SEC for amendments or supplements to a Registration Statement
or related prospectus or related information, and (iii) of the Company's
reasonable determination that a post-effective amendment to a Registration
Statement would be appropriate.

                  f. The Company shall use its best efforts to prevent the
issuance of any stop order or other suspension of effectiveness of a
Registration Statement, or the suspension of the qualification of any of the
Registrable Securities for sale in any jurisdiction and, if such an order or
suspension is issued, to obtain the withdrawal of such order or suspension at
the earliest possible moment and to notify each Investor who holds Registrable
Securities being sold of the issuance of such order and the resolution thereof
or its receipt of actual notice of the initiation or threat of any proceeding
for such purpose.

                  g. The Company shall permit each Investor and a single firm of
counsel, initially Katten Muchin & Zavis or such other counsel as thereafter
designated as selling stockholders' counsel by the Investors who hold a majority
of the Registrable Securities being sold, to review and comment upon a
Registration Statement and all amendments and supplements thereto at least five
(5) business days prior to their filing with the SEC, and not file any document
in a form to which such counsel reasonably objects. The Company shall not submit
a request for acceleration of the effectiveness of a Registration Statement or
any amendment or supplement thereto without the prior approval of such counsel,
which consent shall not be unreasonably withheld.

                  h. The Company shall make available for inspection by (i) any
Investor, and (ii) one firm of attorneys and one firm of accountants or other
agents retained by the Investors (collectively, the "INSPECTORS") all pertinent
financial and other records, and pertinent corporate documents and properties of
the Company (collectively, the "RECORDS"), as shall be reasonably deemed
necessary by each Inspector to enable each Inspector to exercise its due
diligence responsibility, and cause the Company's officers, directors and
employees to supply all 


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information which any Inspector may reasonably request for purposes of such due
diligence; provided, however, that each Inspector shall hold in strict
confidence and shall not make any disclosure (except to an Investor) or use of
any Record or other information which the Company determines in good faith to be
confidential, and of which determination the Inspectors are so notified, unless
(a) the disclosure of such Records is necessary to avoid or correct a
misstatement or omission in any Registration Statement or is otherwise required
under the 1933 Act, (b) the release of such Records is ordered pursuant to a
final, non-appealable subpoena or order from a court or government body of
competent jurisdiction, or (c) the information in such Records has been made
generally available to the public other than by disclosure in violation of this
or any other agreement of which the Inspector has knowledge. Each Investor
agrees that it shall, upon learning that disclosure of such Records is sought in
or by a court or governmental body of competent jurisdiction or through other
means, give prompt notice to the Company and allow the Company, at its expense,
to undertake appropriate action to prevent disclosure of, or to obtain a
protective order for, the Records deemed confidential.

                  i. The Company shall hold in confidence and not make any
disclosure of information concerning an Investor provided to the Company unless
(i) disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other final,
non-appealable order from a court or governmental body of competent
jurisdiction, (iv) such information has been made generally available to the
public other than by disclosure in violation of this Agreement or any other
agreement or (v) such Investor consents to the form and content of any such
disclosure. The Company agrees that it shall, upon learning that disclosure of
such information concerning an Investor is sought in or by a court or
governmental body of competent jurisdiction or through other means, give prompt
written notice to such Investor and allow such Investor, at the Investor's
expense, to undertake appropriate action to prevent disclosure of, or to obtain
a protective order for, such information.

                  j. The Company shall use its best efforts either to (i) cause
all the Registrable Securities covered by a Registration Statement to be listed
on each securities exchange on which securities of the same class or series
issued by the Company are then listed, if any, if the listing of such
Registrable Securities is then permitted under the rules of such exchange, or
(ii) secure designation and quotation of all the Registrable Securities covered
by the Registration Statement on the Nasdaq National Market or, if, despite the
Company's best efforts to satisfy the preceding clause (i) or (ii), the Company
is unsuccessful in satisfying the preceding clause (i) or (ii), to secure the
inclusion for quotation on The Nasdaq SmallCap Market for such Registrable
Securities and, without limiting the generality of the foregoing, to arrange for
at least two market makers to register with the National Association of
Securities Dealers, Inc. ("NASD") as such with respect to such Registrable
Securities. The Company shall pay all fees and expenses in connection with
satisfying its obligation under this Section 3(l).

                  k. The Company shall cooperate with the Investors who hold
Registrable Securities being offered and, to the extent applicable, any managing
underwriter or underwriters, 


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to facilitate the timely preparation and delivery of certificates (not bearing
any restrictive legend) representing the Registrable Securities to be offered
pursuant to a Registration Statement and enable such certificates to be in such
denominations or amounts, as the case may be, as the Investors may reasonably
request and registered in such names as the Investors may request.

                  l. The Company shall take all other reasonable actions
necessary to expedite and facilitate disposition by the Investors of Registrable
Securities pursuant to a Registration Statement.

                  m. The Company shall provide a transfer agent and registrar
for all such Registrable Securities not later than the effective date of such
Registration Statement.

                  n. If requested by an Investor, the Company shall (i)
immediately incorporate in a prospectus supplement or post-effective amendment
such information as the Investors agree should be included therein relating to
the sale and distribution of Registrable Securities; (ii) make all required
filings of such prospectus supplement or post-effective amendment as soon as
notified of the matters to be incorporated in such prospectus supplement or
post-effective amendment; and (iii) supplement or make amendments to any
Registration Statement if requested by a shareholder of such Registrable
Securities.

                  o. The Company shall use its best efforts to cause the
Registrable Securities covered by the applicable Registration Statement to be
registered with or approved by such other governmental agencies or authorities
as may be necessary to consummate the disposition of such Registrable
Securities.

                  p. The Company shall make generally available to its security
holders as soon as practical, but not later than 90 days after the close of the
period covered thereby, an earnings statement (in form complying with the
provisions of Rule 158 under the 1933 Act) covering a twelve-month period
beginning not later than the first day of the Company's fiscal quarter next
following the effective date of the Registration Statement.

                  q. The Company shall otherwise use its best efforts to comply
with all applicable rules and regulations of the SEC in connection with any
registration hereunder.

                  r. Within two (2) business days after the Registration
Statement which includes the Registrable Securities is ordered effective by the
SEC, the Company shall deliver, and shall cause legal counsel for the Company to
deliver, to the transfer agent for such Registrable Securities (with copies to
the Investors whose Registrable Securities are included in such Registration
Statement) confirmation that the Registration Statement has been declared
effective by the SEC in the form attached hereto as Exhibit A.


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         4.       OBLIGATIONS OF THE INVESTORS.

     a. At least five (5) business days prior to the first anticipated filing
date of a Registration Statement, the Company shall notify each Investor in
writing of the information (described in paragraph (b) below) the Company
requires from each such Investor if such Investor elects to have any of such
Investor's Registrable Securities included in such Registration Statement. It
shall be a condition precedent to the obligations of the Company to complete the
registration pursuant to this Agreement with respect to the Registrable
Securities of a particular Investor that such Investor shall furnish to the
Company such information regarding itself, the Registrable Securities held by it
and the intended method of disposition of the Registrable Securities held by it
as shall be reasonably required to effect the registration of such Registrable
Securities and shall execute such documents in connection with such registration
as the Company may reasonably request.

                  b. Each Investor, by such Investor's acceptance of the
Registrable Securities, agrees to cooperate with the Company as reasonably
requested by the Company in connection with the preparation and filing of any
Registration Statement hereunder, unless such Investor has notified the Company
in writing of such Investor's election to exclude all of such Investor's
Registrable Securities from such Registration Statement.

                  c. Each Investor agrees that, upon receipt of any notice from
the Company of the happening of any event of the kind described in Section 3(g)
or the first sentence of Section 3(f), such Investor will immediately
discontinue disposition of Registrable Securities pursuant to any Registration
Statement(s) covering such Registrable Securities until such Investor's receipt
of the copies of the supplemented or amended prospectus contemplated by Section
3(g) or the first sentence of Section 3(f).

         5.       EXPENSES OF REGISTRATION.

                  All reasonable expenses, other than underwriting discounts and
commissions, incurred in connection with registrations, filings or
qualifications pursuant to Sections 2 and 3, including, without limitation, all
registration, listing and qualifications fees, printers and accounting fees, and
fees and disbursements of counsel for the Company and fees and disbursements of
one counsel for the Investors, shall be paid by the Company; provided, however,
that the Company shall not be obligated to pay more than $2,500 of the fees and
disbursements of one counsel for the Investors for each Registration Statement
that is filed.

         6.       INDEMNIFICATION.

                  In the event any Registrable Securities are included in a
Registration Statement under this Agreement:

                  a. To the fullest extent permitted by law, the Company will,
and hereby does, indemnify, hold harmless and defend each Investor who holds
such Registrable Securities, 


                                      -11-
<PAGE>   12
the directors, officers, partners, employees, agents of, and each Person, if
any, who controls, any Investor within the meaning of the 1933 Act or the
Securities Exchange Act of 1934, as amended (the "1934 ACT"), and any
underwriter (as defined in the 1933 Act) for the Investors, and the directors
and officers of, and each Person, if any, who controls, any such underwriter
within the meaning of the 1933 Act or the 1934 Act (each, an "INDEMNIFIED
PERSON"), against any losses, claims, damages, liabilities, judgments, fines,
penalties, charges, costs, attorneys' fees, amounts paid in settlement or
expenses, joint or several (collectively, "CLAIMS"), incurred in investigating,
preparing or defending any action, claim, suit, inquiry, proceeding,
investigation or appeal taken from the foregoing by or before any court or
governmental, administrative or other regulatory agency, body or the SEC,
whether pending or threatened, whether or not an indemnified party is or may be
a party thereto ("INDEMNIFIED DAMAGES"), to which any of them may become subject
insofar as such Claims (or actions or proceedings, whether commenced or
threatened, in respect thereof) arise out of or are based upon: (i) any untrue
statement or alleged untrue statement of a material fact in a Registration
Statement or any post-effective amendment thereto or in any filing made in
connection with the qualification of the offering under the securities or other
"blue sky" laws of any jurisdiction in which Registrable Securities are offered
("BLUE SKY FILING"), or the omission or alleged omission to state a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which the statements therein were made, not
misleading, (ii) any untrue statement or alleged untrue statement of a material
fact contained in any preliminary prospectus if used prior to the effective date
of such Registration Statement, or contained in the final prospectus (as amended
or supplemented, if the Company files any amendment thereof or supplement
thereto with the SEC) or the omission or alleged omission to state therein any
material fact necessary to make the statements made therein, in light of the
circumstances under which the statements therein were made, not misleading, or
(iii) any violation or alleged violation by the Company of the 1933 Act, the
1934 Act, any other law, including, without limitation, any state securities
law, or any rule or regulation thereunder relating to the offer or sale of the
Registrable Securities pursuant to a Registration Statement (the matters in the
foregoing clauses (i) through (iii) being, collectively, "VIOLATIONS"). Subject
to the restrictions set forth in Section 6(d) with respect to the number of
legal counsel, the Company shall reimburse the Investors and each such
underwriter or controlling person, promptly as such expenses are incurred and
are due and payable, for any legal fees or other reasonable expenses incurred by
them in connection with investigating or defending any such Claim.
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(a): (i) shall not apply to a Claim arising
out of or based upon a Violation which occurs in reliance upon and in conformity
with information furnished in writing to the Company by any Indemnified Person
or underwriter for such Indemnified Person expressly for use in connection with
the preparation of the Registration Statement or any such amendment thereof or
supplement thereto, if such prospectus was timely made available by the Company
pursuant to Section 3(c); (ii) with respect to any preliminary prospectus, shall
not inure to the benefit of any such person from whom the person asserting any
such Claim purchased the Registrable Securities that are the subject thereof (or
to the benefit of any person controlling such person) if the untrue statement or
omission of material fact contained in the preliminary prospectus was corrected
in the prospectus, as then amended or supplemented, if such prospectus 


                                      -12-
<PAGE>   13
was timely made available by the Company pursuant to Section 3(c), and the
Indemnified Person was promptly advised in writing not to use the incorrect
prospectus prior to the use giving rise to a violation and such Indemnified
Person, notwithstanding such advice, used it; (iii) shall not be available to
the extent such Claim is based on a failure of the Investor to deliver or to
cause to be delivered the prospectus made available by the Company; and (iv)
shall not apply to amounts paid in settlement of any Claim if such settlement is
effected without the prior written consent of the Company, which consent shall
not be unreasonably withheld. Such indemnity shall remain in full force and
effect regardless of any investigation made by or on behalf of the Indemnified
Person and shall survive the transfer of the Registrable Securities by the
Investors pursuant to Section 9.

                  b. In connection with any Registration Statement in which an
Investor is participating, each such Investor agrees to severally and not
jointly indemnify, hold harmless and defend, to the same extent and in the same
manner as is set forth in Section 6(a), the Company, each of its directors, each
of its officers who signs the Registration Statement, each Person, if any, who
controls the Company within the meaning of the 1933 Act or the 1934 Act and each
other Person selling securities pursuant to the Registration Statement or any
directors, officers or Persons controlling such party (collectively and together
with an Indemnified Person, an "INDEMNIFIED PARTY"), against any Claim or
Indemnified Damages to which any of them may become subject, under the 1933 Act,
the 1934 Act or otherwise, insofar as such Claim or Indemnified Damages arise
out of or are based upon any Violation, in each case to the extent, and only to
the extent, that such Violation occurs in reliance upon and in conformity with
written information furnished to the Company by such Investor expressly for use
in connection with such Registration Statement; and, subject to Section 6(d),
such Investor will reimburse any legal or other expenses reasonably incurred by
them in connection with investigating or defending any such Claim; provided,
however, that the indemnity agreement contained in this Section 6(b) and the
agreement with respect to contribution contained in Section 7 shall not apply to
amounts paid in settlement of any Claim if such settlement is effected without
the prior written consent of such Investor, which consent shall not be
unreasonably withheld; provided, further, however, that the Investor shall be
liable under this Section 6(b) for only that amount of a Claim or Indemnified
Damages as does not exceed the net proceeds to such Investor as a result of the
sale of Registrable Securities pursuant to such Registration Statement. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of such Indemnified Party and shall survive the transfer of
the Registrable Securities by the Investors pursuant to Section 9.
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(b) with respect to any preliminary
prospectus shall not inure to the benefit of any Indemnified Party if the untrue
statement or omission of material fact contained in the preliminary prospectus
was corrected on a timely basis in the prospectus, as then amended or
supplemented.

                  c. The Company shall be entitled to receive indemnities from
underwriters, selling brokers, dealer managers and similar securities industry
professionals participating in any distribution, to the same extent as provided
above, with respect to information such persons so furnished in writing
expressly for inclusion in the Registration Statement.


                                      -13-
<PAGE>   14
                  d. Promptly after receipt by an Indemnified Person or
Indemnified Party under this Section 6 of notice of the commencement of any
action or proceeding (including any governmental action or proceeding) involving
a Claim, such Indemnified Person or Indemnified Party shall, if a Claim in
respect thereof is to be made against any indemnifying party under this Section
6, deliver to the indemnifying party a written notice of the commencement
thereof, and the indemnifying party shall have the right to participate in, and,
to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume control of the defense thereof
with counsel mutually satisfactory to the indemnifying party and the Indemnified
Person or the Indemnified Party, as the case may be; provided, however, that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses to be paid by the indemnifying party, if, in
the reasonable opinion of counsel retained by the indemnifying party, the
representation by such counsel of the Indemnified Person or Indemnified Party
and the indemnifying party would be inappropriate due to actual or potential
differing interests between such Indemnified Person or Indemnified Party and any
other party represented by such counsel in such proceeding. The Company shall
pay reasonable fees for only one separate legal counsel for the Investors, and
such legal counsel shall be selected by the Investors holding a majority in
interest of the Registrable Securities included in the Registration Statement to
which the Claim relates. The Indemnified Party or Indemnified Person shall
cooperate fully with the indemnifying party in connection with any negotiation
or defense of any such action or claim by the indemnifying party and shall
furnish to the indemnifying party all information reasonably available to the
Indemnified Party or Indemnified Person which relates to such action or claim.
The indemnifying party shall keep the Indemnified Party or Indemnified Person
fully apprised at all times as to the status of the defense or any settlement
negotiations with respect thereto. No indemnifying party shall be liable for any
settlement of any action, claim or proceeding effected without its written
consent, provided, however, that the indemnifying party shall not unreasonably
withhold, delay or condition its consent. No indemnifying party shall, without
the consent of the Indemnified Party or Indemnified Person, consent to entry of
any judgment or enter into any settlement or other compromise which does not
include as an unconditional term thereof the giving by the claimant or plaintiff
to such Indemnified Party or Indemnified Person of a release from all liability
in respect to such claim or litigation. Following indemnification as provided
for hereunder, the indemnifying party shall be subrogated to all rights of the
Indemnified Party or Indemnified Person with respect to all third parties, firms
or corporations relating to the matter for which indemnification has been made.
The failure to deliver written notice to the indemnifying party within a
reasonable time of the commencement of any such action shall not relieve such
indemnifying party of any liability to the Indemnified Person or Indemnified
Party under this Section 6, except to the extent that the indemnifying party is
prejudiced in its ability to defend such action.

                  e. The indemnification required by this Section 6 shall be
made by periodic payments of the amount thereof during the course of the
investigation or defense, as and when bills are received or Indemnified Damages
are incurred.


                                      -14-
<PAGE>   15
                  f. The indemnity agreements contained herein shall be in
addition to (i) any cause of action or similar right of the Indemnified Party or
Indemnified Person against the indemnifying party or others, and (ii) any
liabilities the indemnifying party may be subject to pursuant to the law.

         7.       CONTRIBUTION.

                  To the extent any indemnification by an indemnifying party is
prohibited or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided, however, that:
(i) no contribution shall be made under circumstances where the maker would not
have been liable for indemnification under the fault standards set forth in
Section 6; (ii) no Person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from
any seller of Registrable Securities who was not guilty of fraudulent
misrepresentation; and (iii) contribution by any seller of Registrable
Securities shall be limited in amount to the net amount of proceeds received by
such seller from the sale of such Registrable Securities.

         8.       REPORTS UNDER THE 1934 ACT.

                  With a view to making available to the Investors the benefits
of Rule 144 promulgated under the 1933 Act or any other similar rule or
regulation of the SEC that may at any time permit the Investors to sell
securities of the Company to the public without registration ("RULE 144"), the
Company agrees to:

                  a. make and keep public information available, as those terms
are understood and defined in Rule 144;

                  b. file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements (it being understood that
nothing herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents is required for the applicable provisions of Rule 144; and

                  c. furnish to each Investor so long as such Investor owns
Preferred Shares, Warrants or Registrable Securities, promptly upon request, (i)
a written statement by the Company that it has complied with the reporting
requirements of Rule 144, the 1933 Act and the 1934 Act, (ii) a copy of the most
recent annual or quarterly report of the Company and such other reports and
documents so filed by the Company, and (iii) such other information as may be
reasonably requested to permit the investors to sell such securities pursuant to
Rule 144 without registration.


                                      -15-
<PAGE>   16
         9.       ASSIGNMENT OF REGISTRATION RIGHTS.

                  The rights under this Agreement, including the right to have
the Company register Registrable Securities pursuant hereto, shall be
automatically assignable by the Investors to any transferee of all or any
portion of Preferred Shares, Warrants or Registrable Securities if: (i) the
Investor agrees in writing with the transferee or assignee to assign such
rights, and a copy of such agreement is furnished to the Company within a
reasonable time after such assignment; (ii) the Company is, within a reasonable
time after such transfer or assignment, furnished with written notice of (a) the
name and address of such transferee or assignee, and (b) the securities with
respect to which such registration rights are being transferred or assigned;
(iii) immediately following such transfer or assignment the further disposition
of such securities by the transferee or assignee is restricted under the 1933
Act and applicable state securities laws; (iv) at or before the time the Company
receives the written notice contemplated by clause (ii) of this sentence the
transferee or assignee agrees in writing with the Company to be bound by all of
the provisions contained herein; (v) such transfer shall have been made in
accordance with the applicable requirements of the Securities Purchase
Agreement; and (vi) such transferee shall be an "accredited investor" as that
term is defined in Rule 501 of Regulation D promulgated under the 1933 Act.

         10.      AMENDMENT OF REGISTRATION RIGHTS.

                  Provisions of this Agreement may be amended and the observance
thereof may be waived (either generally or in a particular instance and either
retroactively or prospectively), only with the written consent of the Company
and Investors who hold all of the Registrable Securities. Any amendment or
waiver effected in accordance with this Section 10 shall be binding upon each
Investor and the Company.

         11.      MISCELLANEOUS.

                  a. A person or entity is deemed to be a holder of Registrable
Securities whenever such person or entity owns of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more persons or entities with respect to the same
Registrable Securities, the Company shall act upon the basis of instructions,
notice or election received from the registered owner of such Registrable
Securities.


                                      -16-
<PAGE>   17
                  b. Any notices consents, waivers or other communications
required or permitted to be given under the terms of this Agreement must be in
writing and will be deemed to have been delivered (i) upon receipt, when
delivered personally; (ii) upon receipt, when sent by facsimile (provided a
confirmation of transmission is mechanically generated and kept on file by the
sending party); (iii) three (3) days after being sent by U.S. certified mail,
return receipt requested; or (iv) one (1) day after deposit with a nationally
recognized overnight delivery service, in each case properly addressed to the
party to receive the same. The addresses and facsimile numbers for such
communications shall be:

                  If to the Company:

                           Zila, Inc.
                           5227 North Seventh Street
                           Phoenix, Arizona  85014-2800
                           Telephone:  602-266-6700
                           Facsimile:  602-234-2264
                           Attention:  President

                  With a copy to:

                           Streich Lang, P.A.
                           Renaissance One
                           Two North Central Avenue
                           Phoenix, Arizona  85504-2391
                           Telephone:  619-229-5509
                           Facsimile:  619-229-5890
                           Attention:  Kevin Tourek, Esq.

                  If to a Buyer, to its address and facsimile number on the
                  Schedule of Buyers attached hereto, with copies to such
                  Buyer's counsel as set forth on the Schedule of Buyers.

Each party shall provide five (5) days prior notice to the other party of any
change in address, phone number or facsimile number.

                  c. Failure of any party to exercise any right or remedy under
this Agreement or otherwise, or delay by a party in exercising such right or
remedy, shall not operate as a waiver thereof.

                  d. The corporate law of the State of Delaware shall govern all
issues and questions concerning the relative rights and obligations of the
Company and holders of its securities. All other issues and questions concerning
the construction, validity, enforcement and interpretation of this Agreement and
the exhibits and schedules hereto shall be governed by, and construed in
accordance with, the laws of the State of New York, without giving effect to any


                                      -17-
<PAGE>   18
choice of law or conflict of law rules or provisions (whether of the State of
New York or any other jurisdiction) that would cause the application of the laws
of any jurisdiction other than the State of New York. Each party hereby
irrevocably submits to the non-exclusive jurisdiction of the state and federal
courts sitting the City of New York, Borough of Manhattan for the adjudication
of any dispute hereunder or in connection herewith or with any transaction
contemplated hereby or discussed herein, and hereby irrevocably waives, and
agrees not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, that such suit, action
or proceeding is brought in an inconvenient forum or that the venue of such
suit, action or proceeding is improper. Each party hereby irrevocably waives
personal service of process and consents to process being served in any such
suit, action or proceeding by mailing a copy thereof to such party at the
address for such notices to it under this Agreement and agrees that such service
shall constitute good and sufficient service of process and notice thereof.
Nothing contained herein shall be deemed to limit in any way any right to serve
process in any manner permitted by law. If any provision of this Agreement shall
be invalid or unenforceable in any jurisdiction, such invalidity or
unenforceability shall not affect the validity or enforceability of the
remainder of this Agreement in that jurisdiction or the validity or
enforceability of any provision of this Agreement in any other jurisdiction.

                  e. This Agreement, the Securities Purchase Agreement and the
Warrants constitute the entire agreement among the parties hereto with respect
to the subject matter hereof and thereof. There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein and
therein. This Agreement, the Securities Purchase Agreement and the Warrants
supersede all prior agreements and understandings among the parties hereto with
respect to the subject matter hereof and thereof.

                  f. Subject to the requirements of Section 9, this Agreement
shall inure to the benefit of and be binding upon the permitted successors and
assigns of each of the parties hereto.

                  g. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

                  h. This Agreement may be executed in two or more identical
counterparts, each of which shall be deemed an original but all of which shall
constitute one and the same agreement. This Agreement, once executed by a party,
may be delivered to the other party hereto by facsimile transmission of a copy
of this Agreement bearing the signature of the party so delivering this
Agreement.

                  i. Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.


                                      -18-
<PAGE>   19
                  j. All consents and other determinations to be made by the
Investors pursuant to this Agreement shall be made, unless otherwise specified
in this Agreement, by Investors holding a majority of the Registrable
Securities, determined as if all of the Preferred Shares and the Warrants then
outstanding have been converted into or exercised for Registrable Securities.

                  k. The initial number of Registrable Securities included on
any Registration Statement and each increase (if any) to the number of
Registrable Securities included thereon shall be allocated pro rata among the
Investors based on the number of Registrable Securities held by each Investor at
the time of such establishment or increase, as the case may be. In the event an
Investor shall sell or otherwise transfer any of such holder's Registrable
Securities, each transferee shall be allocated a pro rata portion of the number
of Registrable Securities included on a Registration Statement for such
transferor. Any shares of Common Stock included on a Registration Statement and
which remain allocated to any person or entity which does not hold any
Registrable Securities shall be allocated to the remaining Investors, pro rata
based on the number of shares of Registrable Securities then held by such
Investors. For the avoidance of doubt, the number of Registrable Securities held
by any Investor shall be determined as if all shares of Preferred Stock and
Warrants then outstanding were converted into or exercised for Registrable
Securities.

                  l. The language used in this Agreement will be deemed to be
the language chosen by the parties to express their mutual intent and no rules
of strict construction will be applied against any party.


                                      -19-
<PAGE>   20
         IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of day and year first above written.


COMPANY:                            BUYERS:

ZILA, INC.                          OLYMPUS SECURITIES, LTD.



By: /s/ Joseph Hines                By: /s/ Anne Dupuy
   -----------------------------       -----------------------------
Name: Joseph Hines                  Name: Anne Dupuy
      --------------------------    Its: Officer
Its:  President
      --------------------------


                                    NELSON PARTNERS


                                    By: /s/ Anne Dupuy
                                       -----------------------------
                                    Name: Anne Dupuy
                                    Its: Officer



                                    LEONARDO, L.P.

                                    By: Angelo, Gordon & Co., L.P.
                                        General Partner


                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Chief Operating Officer


                                      -20-
<PAGE>   21
                                    GAM ARBITRAGE INVESTMENTS, INC.

                                    By: Angelo, Gordon & Co., L.P.
                                        Investment Adviser


                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Chief Operating Officer


                                    AG SUPER FUND INTERNATIONAL
                                    PARTNERS, L.P.

                                    By: Angelo, Gordon & Co., L.P.
                                        General Partner


                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Chief Operating Officer


                                    RAPHAEL, L.P.



                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Chief Operating Officer


                                    RAMIUS FUND, LTD.

                                    By: AG Ramius Partners, L.L.C.
                                        Investment Adviser


                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Managing Officer


                                    HICK INVESTMENTS, LTD.


                                      -21-
<PAGE>   22
                                    By: AG Ramius Partners, L.L.C.
                                        Investment Adviser


                                    By: /s/ Michael L. Gordon
                                       -----------------------------
                                            Michael L. Gordon
                                            Managing Officer


                                    CAPITAL VENTURES INTERNATIONAL

                                    By: Heights Capital Management, Inc.,
                                        as Agent


                                    By: /s/ Andrew Frost
                                       -----------------------------
                                    Name: Andrew Frost
                                    Its: President


                                      -22-
<PAGE>   23
                               SCHEDULE OF BUYERS





<TABLE>
<CAPTION>
      INVESTOR NAME                           Investor Address               Number of     Investor's Representatives' Address
                                            and Facsimile Number               Units              and Facsimile Number
-------------------------         ---------------------------------------    ---------    ------------------------------------
<S>                               <C>                                        <C>          <C>
Olympus Securities, Ltd.          c/o Leeds Management Services                4,500      Citadel Investment Group, L.L.C.
                                  129 Front Street                                        225 West Washington Street
                                  Hamilton HM12                                           Chicago, Illinois  60606
                                  Bermuda                                                 Attention: Ken Griffin
                                  Attn:  Anne Dupuy                                                  Michael Hughes
                                  Facsimile:  (441) 292-2239                              Facsimile: (312) 368-4347
                                  
                                                                                          Katten Muchin & Zavis
                                                                                          525 West Monroe Street
                                                                                          Chicago, Illinois  60661
                                                                                          Attention: Wesley Nissen
                                                                                                     Kevin Barney
                                                                                          Facsimile: (312) 902-1061
                                  
                                  
Nelson Partners                   c/o Leeds Management Services                5,500      Citadel Investment Group, L.L.C.
                                  129 Front Street                                        225 West Washington Street
                                  Hamilton HM 12                                          Chicago, Illinois  60606
                                  Bermuda                                                 Attention: Ken Griffin
                                  Attn:  Anne Dupuy                                                  Michael Hughes
                                  Facsimile:  (441) 292-2239                              Facsimile: (312) 368-4347
                                  
                                                                                          Katten Muchin & Zavis
                                                                                          525 West Monroe Street
                                                                                          Chicago, Illinois  60661
                                                                                          Attention: Wesley Nissen
                                                                                                     Kevin Barney
                                                                                          Facsimile: (312) 902-1061
                                  
                                  
Leonardo, L.P.                    _Angelo, Gordon & Co., L.P.                  6,100
                                  245 Park Avenue - 26th Floor
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449
                                  
GAM Arbitrage Investments,        _Angelo, Gordon & Co., L.P.                   500
Inc.                              245 Park Avenue - 26th Floor
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449
                                  
AG Super Fund International       _Angelo, Gordon & Co., L.P.                   500
Partners, L.P.                    245 Park Avenue - 26th Floor
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449
                                  
Raphael, L.P.                     _Angelo, Gordon & Co., L.P.                  1,000
                                  245 Park Avenue - 26th Floor
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449
                                  
Ramius Fund, Ltd.                 _Angelo, Gordon & Co., L.P.                  1,400                   
                                  245 Park Avenue - 26th Floor
</TABLE>
                                  
                                 
                                      -23-
<PAGE>   24
<TABLE>
<CAPTION>
      INVESTOR NAME                           Investor Address               Number of     Investor's Representatives' Address
                                            and Facsimile Number               Units              and Facsimile Number
-------------------------         ---------------------------------------    ---------    ------------------------------------
<S>                               <C>                                        <C>          <C>
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449

Hick Investments, Ltd.            _Angelo, Gordon & Co., L.P.                   500
                                  245 Park Avenue - 26th Floor
                                  New York, New York  10167
                                  Attn:  Gary Wolf
                                  Facsimile:  (212) 867-6449

Capital Ventures International    _Heights Capital Management, Inc.           10,000      Klehr, Harrison, Harvey,
                                  425 California Street                                     Branzburg & Ellers
                                  Suite 1100                                              1401 Walnut Street
                                  San Francisco, California  94104                        Philadelphia, Pennsylvania  19109
                                  Attn:  Michael Spolan                                   Attention:  Steve Burdumy
                                  Facsimile:  (415) 403-6525                                          Gerald Stahlecker
                                                                                          Facsimile:  (215) 568-6603
</TABLE>


                                      -24-
<PAGE>   25
                                                                       EXHIBIT A


                         FORM OF NOTICE OF EFFECTIVENESS
                            OF REGISTRATION STATEMENT

_______________________________
ATTN: ___________________

                  RE:      ZILA, INC.

Ladies and Gentlemen:

         We are counsel to Zila, Inc., a Delaware corporation (the "COMPANY"),
and have represented the Company in connection with that certain Securities
Purchase Agreement (the "PURCHASE AGREEMENT") entered into by and among the
Company and the buyers named therein (collectively, the "HOLDERS") pursuant to
which the Company issued to the Holders shares of its Series A Redeemable
Convertible Preferred Stock, par value $.001 per share (the "PREFERRED SHARES"),
and warrants to purchase _____ shares of the Company's common stock, par value
$.001 per share (the "COMMON STOCK"), for each Preferred Share, subject to
adjustment (the "WARRANTS"). Pursuant to the Purchase Agreement, the Company
also has entered into a Registration Rights Agreement with the Holders (the
"REGISTRATION RIGHTS AGREEMENT") pursuant to which the Company agreed, among
other things, to register the Registrable Securities (as defined in the
Registration Rights Agreement), including the shares of Common Stock issuable
upon conversion of the Preferred Shares and exercise of the Warrants, under the
Securities Act of 1933, as amended (the "1933 ACT"). In connection with the
Company's obligations under the Registration Rights Agreement, on ____________
___, 1997, the Company filed a Registration Statement on Form S-3 (File No.
333-_____________) (the "REGISTRATION STATEMENT") with the Securities and
Exchange Commission (the "SEC") relating to the Registrable Securities which
names each of the Holders as a selling stockholder thereunder.

         In connection with the foregoing, we advise you that a member of the
SEC's staff has advised us by telephone that the SEC has entered an order
declaring the Registration Statement effective under the 1933 Act at [ENTER TIME
OF EFFECTIVENESS] on [ENTER DATE OF EFFECTIVENESS] and we have no knowledge,
after telephonic inquiry of a member of the SEC's staff, that any stop order
suspending its effectiveness has been issued or that any proceedings for that
purpose are pending before, or threatened by, the SEC and the Registrable
Securities are available for resale under the 1933 Act pursuant to the
Registration Statement.

                                    Very truly yours,

                                    STREICH LANG, P.A.

                                    By: ________________________
cc: [LIST NAMES OF HOLDERS]


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