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                                                                   EXHIBIT 10-Ac

                                   ZILA, INC.

                              1997 STOCK AWARD PLAN

                             STOCK OPTION AGREEMENT

      Unless otherwise defined herein, the terms defined in the Plan shall have
the same defined meanings in this Option Agreement.

I.    NOTICE OF STOCK OPTION GRANT

      [OPTIONEE'S NAME AND ADDRESS]

      The undersigned Optionee has been granted an Option to purchase Common
Stock of the Company, subject to the terms and conditions of the Plan and this
Option Agreement, as follows:

      Grant Number                         _________________________

      Date of Grant                        _________________________

      Vesting Commencement Date            _________________________

      Exercise Price per Share             $________________________

      Total Number of Shares Granted       _________________________

      Total Exercise Price                 $________________________

      Type of Option:                      [Incentive/Nonstatutory Stock Option]

      Maximum Term/Expiration Date:        _________________________

      Vesting Schedule:

      This Option shall vest and become exercisable in accordance with the
following:

      (Describe) All vesting is subject to Optionee continuing to be a Service
Provider on each vesting date.

II.   AGREEMENT

      1. Grant of Option. The Administrator of the Company hereby grants to the
person named in the Notice of Grant (the "Optionee"), an option (the "Option")
to purchase the number of shares of Common Stock set forth in the Notice of
Grant, at the exercise price per share of Common Stock set forth in the Notice
of Grant (the "Exercise Price"), and subject to the terms and conditions of the
Plan, which is incorporated herein by reference. In the event of a conflict
between the terms and conditions of the Plan and this Option Agreement, the
terms and conditions of the Plan shall prevail.

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            This Option is [NOT] intended to qualify as an Incentive Stock
Option as defined in Section 422 of the Code. [Instead, this Option is a
Nonstatutory Stock Option.]

      2. Vesting. Subject to the limitations contained herein, the Option will
vest as provided in Optionee's Grant Notice, provided that vesting will cease
upon the termination of Optionee's continuous service as a Service Provider.

      3. Number of Shares and Exercise Price. The number of shares of Common
Stock subject to the Option and the Exercise Price per share referenced in the
Grant Notice may be adjusted from time to time for Capitalization Adjustments,
as provided in the Plan.

      4. Exercise.

            (a) Optionee may exercise the vested portion of the Option at any
time during the term of the Option (as described in Section 5). In order to
exercise the vested portion of the Option, Optionee must deliver a Notice of
Exercise (in a form designated by the Company) together with the Exercise Price
to the Secretary of the Company, or to such other person as the Company may
designate, during regular business hours, together with such additional
documents as the Company may then require.

            (b) Optionee may not exercise the unvested portion of the Option.

            (c) By exercising the Option, Optionee agrees that, as a condition
to any exercise of the Option, the Company may require Optionee to enter into an
arrangement providing for the payment by Optionee to the Company of any tax
withholding obligation of the Company arising by reason of (1) the exercise of
the Option or (2) the disposition of shares of Common Stock acquired upon such
exercise.

            (d) No shares of Common Stock shall be issued pursuant to the
exercise of an Option unless such issuance and such exercise complies with
applicable laws. Assuming such compliance, for income tax purposes the shares of
Common Stock shall be considered transferred to the Optionee on the date on
which the Option is exercised with respect to such shares of Common Stock.

            (e) The Option may be exercised only for whole shares of Common
Stock and not for a fraction of a share of Common Stock.

      5. Term. Optionee may not exercise the Option before the commencement of
its term or after its term expires. The term of the Option commences on the Date
of Grant and expires upon the EARLIEST of the following:

            (a) With respect to the unvested portion of the Option, upon
termination of Optionee's Continuous Service;

            (b) With respect to the vested portion of the Option, three (3)
months after the termination of Continuous Service for any reason other than
Optionee's Disability, death or a termination for Cause, provided that if during
any part of such three (3) month period the Option is not exercisable solely
because of the condition set forth in Section 7 below relating to "Securities
Law Compliance," the Option shall not expire until the earlier of the Expiration
Date or until it shall

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have been exercisable for an aggregate period of three (3) month after the
termination of Optionee's Continuous Service.

                  Notwithstanding the foregoing, if, following the termination
of the Optionee's Continuous Service pursuant to this Section 5(b), the exercise
of the Option or sale of shares of Common Stock received upon the Option's
exercise the issuance or sale of shares of Common Stock received upon exercise
of the Option would violate Applicable Laws or any Company-mandated trading
policy (together, the "Restrictions"), then the Option shall terminate on the
earlier of (i) the expiration of the term of the Option as set forth in the
Grant Notice or (ii) the expiration of a period of three (3) months after the
termination of the Optionee's Continuous Service during which the exercise of
the Option would not be in violation of such Restrictions;

            (c) With respect to the vested portion of the Option, immediately
upon the termination of Continuous Service for Cause;

            (d) With respect to the vested portion of the Option, twelve (12)
months after the termination of the Optionee's Continuous Service due to
Optionee's Disability or death;

            (e) Immediately prior to the close of certain Corporate
Transactions, pursuant to Section 9 of the Plan

            (f) the Expiration Date indicated in Optionee's Grant Notice; or

            (g) the day before the tenth (10th) anniversary of the Date of
Grant.

      6. Securities Law Compliance. Notwithstanding anything to the contrary
contained herein, Optionee may not exercise the Option unless the shares of
Common Stock issuable upon such exercise are then registered under the
Securities Act or, if such shares of Common Stock are not then so registered,
the Company has determined that such exercise and issuance would be exempt from
the registration requirements of the Securities Act. The exercise of the Option
must also comply with all Applicable laws and regulations governing the Option,
and Optionee may not exercise the Option if the Company determines that such
exercise would not be in material compliance with applicable laws.

      7. Lock-Up Period. Optionee hereby agrees that, if so requested by the
Company or any representative of the underwriters (the "Managing Underwriter")
in connection with any registration of the offering of any securities of the
Company, Optionee shall not sell or otherwise transfer any shares of Common
Stock or other securities of the Company during the 180-day period (or such
other period as may be requested in writing by the Managing Underwriter and
agreed to in writing by the Company) (the "Market Standoff Period") following
the effective date of a registration statement of the Company. Such restriction
shall apply only to the first registration statement of the Company to become
effective that includes securities to be sold on behalf of the Company to the
public in an underwritten public offering. The Company may impose stop-transfer
instructions with respect to securities subject to the foregoing restrictions
until the end of such Market Standoff Period.

      8. Method of Payment. Payment of the exercise price is due in full upon
exercise of all or any part of the Option. Payment of the aggregate Exercise
Price shall be by either of the following, or a combination thereof, at the
election of the Optionee:

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            (a) cash or check;

            (b) In the Company's sole discretion at the time the Option is
exercised and provided that at the time of exercise the shares of Common Stock
are publicly traded and quoted regularly in The Wall Street Journal, pursuant to
a program developed under Regulation T as promulgated by the Federal Reserve
Board that, prior to the issuance of shares of Common Stock (or securities into
which the shares of Common Stock have been converted), results in either the
receipt of cash (or check) by the Company or the receipt of irrevocable
instructions to pay the aggregate exercise price to the Company from the sales
proceeds.

      9. Non-Transferability of Option. This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution and
may be exercised during the lifetime of Optionee only by Optionee. The terms of
the Plan and this Option Agreement shall be binding upon the executors,
administrators, heirs, successors and assigns of the Optionee.

      10. Withholding Obligations.

            (a) At the time Optionee exercises the Option, in whole or in part,
or at any time thereafter as requested by the Company, Optionee hereby authorize
withholding from payroll and any other amounts payable to Optionee, and
otherwise agree to make adequate provision for (including by means of a
"cashless exercise" pursuant to a program developed under Regulation T as
promulgated by the Federal Reserve Board to the extent permitted by the
Company), any sums required to satisfy the federal, state, local and foreign tax
withholding obligations of the Company or an affiliate, if any, which arise in
connection with the Option.

            (b) Upon Optionee's request and subject to approval by the Company,
in its sole discretion, and compliance with any applicable conditions or
restrictions of law, the Company may withhold from fully vested shares of Common
Stock otherwise issuable to Optionee upon the exercise of the Option a number of
whole shares of Common Stock having a Fair Market Value, determined by the
Company as of the date of exercise, not in excess of the minimum amount of tax
required to be withheld by law. If the date of determination of any tax
withholding obligation is deferred to a date later than the date of exercise of
the Option, stock withholding pursuant to the preceding sentence shall not be
permitted unless Optionee make a proper and timely election under Section 83(b)
of the Code, covering the aggregate number of shares of Common Stock acquired
upon such exercise with respect to which such determination is otherwise
deferred, to accelerate the determination of such tax withholding obligation to
the date of exercise of the Option. Notwithstanding the filing of such election,
shares of Common Stock shall be withheld solely from fully vested shares of
Common Stock determined as of the date of exercise of the Option that are
otherwise issuable to Optionee upon such exercise. Any adverse consequences to
Optionee arising in connection with such share withholding procedure shall be
Optionee's sole responsibility.

            (c) Optionee may not exercise the Option unless the tax withholding
obligations of the Company or any affiliate are satisfied. Accordingly, Optionee
may not be able to exercise the Option when desired even though the Option is
vested, and the Company shall have no obligation to issue a certificate for such
shares of Common Stock.

      11. Tax Consequences. The Company makes no representations regarding the
tax treatment related to the Option or its exercise. THE OPTIONEE SHOULD CONSULT
A TAX

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ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES OF COMMON
STOCK.

            Optionee agrees that Optionee may be subject to income and
employment tax withholding by the Company on the compensation income recognized
by the Optionee and that the Company shall not be required to issue shares of
Common Stock upon the exercise of the Option unless Optionee adequately provides
for the Company to satisfy its withholding obligations.

      12. Entire Agreement; Governing Law. The Plan is incorporated herein by
reference. The Plan and this Option Agreement constitute the entire agreement of
the parties with respect to the subject matter hereof and supersede in their
entirety all prior undertakings and agreements of the Company and Optionee with
respect to the subject matter hereof, and may not be modified adversely to the
Optionee's interest except by means of a writing signed by the Company and
Optionee. This agreement is governed by the internal substantive laws but not
the choice of law rules of Arizona.

      13. No Guarantee of Continued Service. OPTIONEE ACKNOWLEDGES AND AGREES
THAT THE VESTING OF SHARES OF COMMON STOCK PURSUANT TO THE VESTING SCHEDULE
HEREOF IS EARNED ONLY BY CONTINUOUS SERVICE AT THE WILL OF THE COMPANY (NOT
THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS OPTION OR ACQUIRING SHARES OF
COMMON STOCK HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS
AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET
FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED
ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT
ALL, AND SHALL NOT INTERFERE IN ANY WAY WITH OPTIONEE'S RIGHT OR THE COMPANY'S
RIGHT TO TERMINATE OPTIONEE'S RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME,
WITH OR WITHOUT CAUSE.

      Optionee acknowledges receipt of a copy of the Plan and represents that he
or she is familiar with the terms and provisions thereof, and hereby accepts
this Option subject to all of the terms and provisions thereof. Optionee has
reviewed the Plan and this Option in their entirety, has had an opportunity to
obtain the advice of counsel prior to executing this Option and fully
understands all provisions of the Option. Optionee hereby agrees to accept as
binding, conclusive and final all decisions or interpretations of the
Administrator upon any questions arising under the Plan or this Option. Optionee
further agrees to notify the Company upon any change in the residence address
indicated below.

OPTIONEE:                                   ZILA, INC.

____________________________________        By: _______________________________
Signature

____________________________________        Name: ________________________
Print Name
                                            Title: _______________________

____________________________________

____________________________________
Residence Address

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                                    EXHIBIT A

                                   ZILA, INC.

                              1997 STOCK AWARD PLAN

                                 EXERCISE NOTICE

Zila, Inc.
[Address]

Attention: [NAME AND/OR TITLE]

      1. Exercise of Option. Effective as of today, ___________, _____, the
undersigned ("Optionee") hereby elects to exercise Optionee's option to purchase
_________ shares of Common Stock (the "Shares") of Zila, Inc. (the "Company")
under and pursuant to the 1997 Stock Award Plan (the "Plan") and the Stock
Option Agreement dated ________, 200___ (the "Option Agreement").

      2. Delivery of Payment. Purchaser herewith delivers to the Company the
full purchase price of the shares of Common Stock, as set forth in the Option
Agreement.

      3. Representations of Optionee. Optionee acknowledges that Optionee has
received, read and understood the Plan and the Option Agreement and agrees to
abide by and be bound by their terms and conditions.

      4. Rights as Shareholder. Until the issuance of the shares of Common Stock
(as evidenced by the appropriate entry on the books of the Company or of a duly
authorized transfer agent of the Company), no right to vote or receive
allocations of profits or losses or any other rights as a shareholder shall
exist with respect to the shares of Common Stock, notwithstanding the exercise
of the Option. The shares of Common Stock shall be issued to the Optionee as
soon as practicable after the Option is exercised. No adjustment shall be made
for a dividend or other right for which the record date is prior to the date of
issuance except as provided in Section 10(c) of the Plan.

      5. Tax Consultation. Optionee understands that Optionee may suffer adverse
tax consequences as a result of Optionee's purchase or disposition of the shares
of Common Stock. Optionee represents that Optionee has consulted with any tax
consultants Optionee deems advisable in connection with the purchase or
disposition of the shares of Common Stock and that Optionee is not relying on
the Company for any tax advice.

      6. Successors and Assigns. The Company may assign any of its rights under
this Agreement to single or multiple assignees, and this Agreement shall inure
to the benefit of the successors and assigns of the Company. Subject to the
restrictions on transfer herein set forth, this Agreement shall be binding upon
Optionee and his or her heirs, executors, administrators, successors and
assigns.

      7. Interpretation. Any dispute regarding the interpretation of this
Agreement shall be submitted by Optionee or by the Company forthwith to the
Administrator which shall review such dispute at its next regular meeting. The
resolution of such a dispute by the Administrator shall be final and binding on
all parties.

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      8. Governing Law; Severability. This Agreement is governed by the internal
substantive laws but not the choice of law rules, of Arizona.

      9. Entire Agreement. The Plan and Option Agreement are incorporated herein
by reference. This Agreement, the Plan and the Option Agreement constitute the
entire agreement of the parties with respect to the subject matter hereof and
supersede in their entirety all prior undertakings and agreements of the Company
and Optionee with respect to the subject matter hereof, and may not be modified
adversely to the Optionee's interest except by means of a writing signed by the
Company and Optionee.

Submitted by:                               Accepted by:

OPTIONEE:                                   ZILA, INC.

____________________________________        By: ________________________________
Signature
                                            Name:_______________________________
____________________________________
Print Name                                  Title:______________________________

Address:
                                            ____________________________________
                                            Date Received

____________________________________

____________________________________

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