Document:

<PAGE>   1
                                                                   EXHIBIT 4.18

THIS WARRANT AND THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND MAY NOT BE SOLD, OFFERED FOR SALE, ASSIGNED, TRANSFERRED OR OTHERWISE
DISPOSED OF, UNLESS REGISTERED PURSUANT TO THE PROVISIONS OF THE SECURITIES ACT
OR AN OPINION OF COUNSEL IS OBTAINED STATING THAT SUCH DISPOSITION IS IN
COMPLIANCE WITH AN AVAILABLE EXEMPTION FROM SUCH REGISTRATION.

April 17, 2000

                                  VIRAGEN, INC.

             (Incorporated under the laws of the State of Delaware)

               WARRANT FOR THE PURCHASE OF SHARES OF COMMON STOCK

No. NS-01

         FOR VALUE RECEIVED, VIRAGEN, INC. (the "Company"), a Delaware
corporation, hereby certifies that Nassau Securities, Int'l (the "Holder"), is
entitled, subject to the provisions of the Warrant, to purchase from the Company
up to 50,000 fully paid and non-assessable shares of Common Stock at a price of
US$1.94 per share (the "Exercise Price").

         The term "Common Stock" means the Common Stock, par value $.01 per
share, of the Company as constituted on April 17, 2000 (the "Base Date"). The
number of shares of Common Stock to be received upon the exercise of this
Warrant may be adjusted from time to time as hereinafter set forth. The shares
of Common Stock deliverable upon such exercise, and as adjusted from time to
time, are hereinafter referred to as "Warrant Stock." The term "Other
Securities" means any other equity or debt securities that may be issued by the
Company in addition thereto or in substitution for the Warrant Stock. The term
"Company" means and includes the corporation named above as well as (i) any
immediate or more remote successor corporation resulting from the merger or
consolidation of such corporation (or any immediate or more remote successor
corporation of such corporation) with another corporation, or (ii) any
corporation to which such corporation (or any immediate or more remote successor
corporation of such corporation) has transferred its property or assets as an
entirety or substantially as an entirety.

         Upon receipt by the Company of evidence satisfactory to it of the loss,
theft, destruction or mutilation of this Warrant, and (in the case of loss,
theft or destruction) of satisfactory indemnification, and upon surrender and
cancellation of this Warrant, if mutilated, the Company shall execute and
deliver a new Warrant of like tenor and date. Any such new Warrant executed and

<PAGE>   2

delivered shall constitute an additional contractual obligation on the part of
the Company, whether or not this Warrant so lost, stolen, destroyed or mutilated
shall be at any time enforceable by anyone.

         The Holder agrees with the Company that this Warrant is issued, and all
the rights hereunder shall be held subject to, all of the conditions,
limitations and provisions set forth herein.

1. EXERCISE OF WARRANT. Subject to the provisions herein, this Warrant shall
vest and become exercisable in whole as of the date hereof for a five (5) year
period commencing on the date hereof (the "Expiration Date") or, if such day is
a day on which banking institutions in New York are authorized by law to close,
then on the next succeeding day that shall not be such a day, by presentation
and surrender of this Warrant to the Company at its principal office, or at the
office of its stock transfer agent, if any, with the Warrant Exercise Form
attached hereto duly executed and accompanied by payment (either in cash or by
certified or official bank check, payable to the order of the Company) of the
Exercise Price for the number of shares specified in such form and instruments
of transfer, if appropriate, duly executed by the Holder or his or her duly
authorized attorney. If this Warrant should be exercised in part only, the
Company shall, upon surrender of this Warrant for cancellation, execute and
deliver a new Warrant evidencing the rights of the Holder thereof to purchase
the balance of the shares purchasable hereunder. The Company shall pay any and
all documentary stamp or similar issue or transfer taxes payable in respect of
the issue or delivery of shares of Common Stock on exercise of this Warrant.

2. RESERVATION OF SHARES. The Company will at all times reserve for issuance and
delivery upon exercise of this Warrant all shares of Common Stock or other
shares of capital stock of the Company (and Other Securities) from time to time
receivable upon exercise of this Warrant. All such shares (and Other Securities)
shall be duly authorized and, when issued upon such exercise, shall be validly
issued, fully paid and non-assessable and free of all preemptive rights.

3. FRACTIONAL SHARES. No fractional shares or scrip representing fractional
shares shall be issued upon the exercise of this Warrant, but the Company shall
pay the holder an amount equal to the fair market value of such fractional share
of Common Stock in lieu of each fraction of a share otherwise called for upon
any exercise of this Warrant. For purposes of this Warrant, the fair market
value of a share of Common Stock shall be determined as follows:

    (a) If the Common Stock is listed on a National Securities Exchange or
    admitted to unlisted trading privileges on such exchange or listed for
    trading on the NASDAQ system, the current market value shall be the last
    reported sale price of the Common Stock on such exchange or system on the
    last business day prior to the date of exercise of this Warrant or, if no
    such sale is made on such day, the average of the closing bid and asked
    prices for such day on such exchange or system; or

                                       2
<PAGE>   3

    (b) If the Common Stock is not so listed or admitted to unlisted trading
    privileges, the current market value shall be the mean of the last reported
    bid and asked prices reported by the National Quotation Bureau, Inc. on the
    last business day prior to the date of the exercise of this Warrant; or

    (c) If the Common Stock is not so listed or admitted to unlisted trading
    privileges and bid and asked prices are not so reported, the current market
    value shall be an amount, not less than book value thereof as at the end of
    the most recent fiscal year of the Company ending prior to the date of the
    exercise of the Warrant, determined in such reasonable manner as may be
    prescribed by the Board of Directors of the Company.

4. RIGHTS OF THE HOLDER. The Holder shall not, by virtue hereof, be entitled to
any rights of a stockholder in the Company, either at law or in equity, and the
rights of the Holder are limited to those expressed in this Warrant.

5. ANTI-DILUTION PROVISIONS.

    5.1 ADJUSTMENT FOR RECAPITALIZATION. If the Company shall at any time
subdivide its outstanding shares of Common Stock (or Other Securities at the
time receivable upon the exercise of the Warrant) by recapitalization,
reclassification or split-up thereof, or if the Company shall declare a stock
dividend or distribute shares of Common Stock to its stockholders, the number of
shares of Common Stock subject to this Warrant immediately prior to such
subdivision shall be proportionately increased, and the Exercise Price shall be
proportionately decreased, and if the Company shall at any time combine the
outstanding shares of Common Stock by recapitalization, reclassification or
combination thereof, the number of shares of Common Stock subject to this
Warrant immediately prior to such combination shall be proportionately
decreased, and the Exercise Price shall be proportionately increased. Any such
adjustments pursuant to this Section 5.1 shall be effective at the close of
business on the effective date of such subdivision or combination, or if any
adjustment is the result of a stock dividend or distribution, then the effective
date for such adjustment based thereof shall be the record date therefor.

    5.2 ADJUSTMENT FOR REORGANIZATION, CONSOLIDATION, MERGER, ETC. In case of
any reorganization of the Company (or any other corporation, the securities of
which are at the time receivable on the exercise of this Warrant) after the Base
Date or in case after such date the Company (or any such other corporation)
shall consolidate with or merge into another corporation or convey all or
substantially all of its assets to another corporation, then, and in each such
case, the Holder of this Warrant upon the exercise thereof as provided in
Section 1 at any time after the consummation of such reorganization,
consolidation, merger or conveyance shall be entitled to receive, in lieu of the
securities and property receivable upon the exercise of this Warrant prior to

                                       3
<PAGE>   4

such consummation, the securities or property to which such Holder would have
been entitled upon such consummation if such Holder had exercised this Warrant
immediately prior thereto; in each such case, the terms of this Warrant shall be
applicable to the securities or property receivable upon the exercise of this
Warrant after such consummation.

    5.3 NOTIFICATION AS TO ADJUSTMENTS. In each case of an adjustment in the
number of shares of Common Stock receivable on the exercise of the Warrant, the
Company at its expense will promptly compute such adjustment in accordance with
the terms of the Warrant and will notify the Holder in writing of such
adjustment within 30 days of the effective date of such adjustment. When
appropriate, notice may be given in advance as part of notices required to be
mailed to the Holder pursuant to Section 5.4 hereof.

    5.4 NOTICES OF RECORD DATE, ETC. In case:

         (a) the Company shall take a record of the holders of its Common Stock
(or Other Securities at the time receivable upon the exercise of the Warrant)
for the purpose of entitling them to receive any dividend (other than a cash
dividend at the same rate as the rate of the last cash dividend theretofore
paid) or other distribution, or any right to subscribe for, purchase or
otherwise acquire any shares of stock of any class or any other securities, or
to receive any other right; or

         (b) of any capital reorganization of the Company, any reclassification
of the capital stock of the Company, any consolidation or merger of the Company
with or into another corporation, or any conveyance of all or substantially all
of the assets of the Company to another corporation; or

         (c) of any voluntary or involuntary dissolution, liquidation or winding
up of the Company, then, and in each such case, the Company shall mail or cause
to be mailed to each Holder of the Warrant at the time outstanding a notice
specifying, as the case may be, (i) the date on which a record is to be taken
for the purpose of such dividend, distribution or right, and stating the amount
and character of such dividend, distribution or right, or (ii) the date on which
such reorganization, reclassification, consolidation, merger, conveyance,
dissolution, liquidation or winding up is to take place, and the time, if any,
is to be fixed, as to which the holders of record of Common Stock (or such Other
Securities at the time receivable upon the exercise of the Warrant) shall be
entitled to exchange their shares of Common Stock (or such Other Securities) for
securities or other property deliverable upon such reorganization,
reclassification, consolidation, merger, conveyance, dissolution, liquidation or
winding up. Such notice shall be mailed at least 20 days prior to the date
therein specified, and the Warrant may be exercised prior to said date during
the term of the Warrant.

6. TRANSFER TO COMPLY WITH THE SECURITIES ACT. This Warrant and any Warrant
Stock or Other Securities may not be sold, assigned, transferred, pledge,
hypothecated or otherwise disposed of except as follows: (a) to a person who, in
the opinion of counsel to the Company, is a person to whom this Warrant or the

                                       4
<PAGE>   5

Warrant Stock or Other Securities may legally be transferred without
registration and without the delivery of a current prospectus under the
Securities Act with respect thereto and then only against receipt of an
agreement of such person to comply with the provisions of this Section 6 with
respect to any resale or other disposition of such securities; or (b) to any
person upon delivery of a prospectus then meeting the requirements of the
Securities Act relating to such securities and the offering thereof for such
sale or disposition, and thereafter to all successive assignees.

7. LEGEND. Unless the shares of Warrant Stock or Other Securities have been
registered under the Securities Act, upon exercise of any of the Warrants and
the issuance of any of the shares of Warrant Stock, all certificates
representing shares will bear on the face thereof substantially the following
legend:

         THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
         UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD,
         OFFERED FOR SALE, ASSIGNED, TRANSFERRED OR OTHERWISE DISPOSED OF UNLESS
         REGISTERED PURSUANT TO THE PROVISIONS OF THAT ACT OR UNLESS AN OPINION
         OF COUNSEL TO THE CORPORATION IS OBTAINED STATING THAT SUCH DISPOSITION
         IS IN COMPLIANCE WITH AN AVAILABLE EXEMPTION FROM SUCH REGISTRATION.

8. NOTICES. All notices required hereunder shall be in writing and shall be
deemed given when sent via facsimile, delivered personally or within two days
after mailing when mailed by certified or registered mail, return receipt
requested, to the Company or the Holder, as the case may be, for whom such
notice is intended at the address of such party as set forth on the first page,
or at such other address of which the Company or the Holder has been advised by
notice hereunder.

9. APPLICABLE LAW. The Warrant is issued under and shall for all purposes be
governed by and construed in accordance with the laws of the State of Delaware.

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed on
its behalf, in its corporate name, by its duly authorized officer, all as of the
day and year first above written.

                                               VIRAGEN, INC.

                                               By: /s/ Dennis W. Healey
                                                  -----------------------------
                                                   Dennis W. Healey
                                                   Executive Vice President

                                       5
<PAGE>   6

                              WARRANT EXERCISE FORM

         The undersigned hereby irrevocably elects to exercise the within
Warrant to the extent of purchasing _________ shares of Common Stock of Viragen,
Inc., a Delaware corporation, and hereby makes payment of $__________ in payment
therefore.

                                                    ---------------------------
                                                    Signature

                                                    ---------------------------
                                                    Signature, if jointly held

                                                    ---------------------------
                                                    Date

                       INSTRUCTIONS FOR ISSUANCE OF STOCK
         (If other than to the registered holder of the within Warrant)

Name
     ------------------------------------------------------------
         (Please typewrite or print in block letters)

Address
     ------------------------------------------------------------

     ------------------------------------------------------------

Social Security or
Taxpayer Identification Number
                               ----------------------------------

Phone and Fax #'s:
                   ----------------------------------------------

                                       6
<PAGE>   7

                                 ASSIGNMENT FORM

         FOR VALUE RECEIVED
                            --------------------------------------------
hereby sells, assigns and transfers unto
                                         -------------------------------

--------------------------------------------
(Please typewrite or print in block letters)

the right to purchase Common Stock of Viragen, Inc., a Delaware corporation,
represented by this Warrant to the extend of shares as to which such right is
exercisable and does hereby irrevocably constitute and appoint _______________
Attorney to transfer the same on the books of the Company with full power of
substitution in the premises.

Dated:                 , 200
      ----------------      --

                                                   ----------------------------
                                                   Signature

                                                   ----------------------------
                                                   Signature, if jointly held

                                       7<PAGE>   1
                                                                   EXHIBIT 4.19

                                    EXHIBIT A

                             STOCK OPTION AGREEMENT

STOCK OPTION AGREEMENT, dated as of February 7, 2000 (the "Effective Date")
between Viragen, Inc. a Delaware Corporation (the "Company") and Gerald Smith
("Optionee").

The Company hereby grants to Optionee a Non-Statutory Option ("NSO") to acquire
Common Stock, par value $.01 per share, of the Company (the "Common Stock"),
subject to the following terms and conditions:

         1. GRANT OF OPTION. The Company hereby grants to Optionee (the
"Option") to purchase up to 1,000,000 shares of Common Stock (the "Shares"), to
be transferred upon the exercise thereof, fully paid and nonassessable.

Optionee and the Company acknowledge that this Option supercedes and replaces
Optionees' right to purchase 1,000,000 shares, exercisable at $0.50 per share
for a period of five (5) years from the grant date, granted by the Company on
October 6, 1995 ("Replaced Option") and that the Replaced Option is hereby
cancelled.

         2. EXERCISE PRICE. The exercise price of the Shares subject to the
Option shall be at $0.50 per share. The Company shall pay all original issue or
transfer taxes upon the exercise of the Option by Optionee.

         3. EXERCISABILITY OF OPTION; RIGHTS AND PRIVILEGES. Subject to the
provisions of Paragraph 6 hereof, the Option shall be exercisable by Optionee in
whole or in part, at any time and from time to time, commencing on the Effective
Date (the "Exercise Date") through October 5, 2003

All granted but unexercised Options shall continue to be fully exercisable in
accordance with the provisions herein:

             (i) if there occurs any corporate transaction (which shall include
a series of corporate transactions occurring within 60 days or occurring
pursuant to a plan), that has the result that shareholders of the Company
immediately before such transaction cease to own at least 66 2/3 percent of the
voting stock of the Company in a (a) reorganization, (b) consolidation, (c)
merger, (d) liquidation or (e) a similar of corporate transaction;

             (ii) if the shareholders of the Company shall approve a plan of
merger, consolidation, reorganization, liquidation or dissolution in which the
Company does not survive (unless the approved merger, consolidation,
reorganization, liquidation or dissolution is subsequently abandoned); or

<PAGE>   2

             (iii) if the shareholders of the Company shall approve a plan for
the sale, lease, exchange or other disposition of all or substantially all the
property and assets of the Company (unless such plan is subsequently abandoned).

         4. NON-ASSIGNABILITY OF OPTION. The Option shall not be given, granted,
sold, exchanged, transferred, pledged, encumbered, assigned or otherwise
disposed of by Optionee, other than by will or the laws of descent and
distribution, and during the lifetime of Optionee, shall not be exercisable by
any other person, but only by Optionee.

         5. METHOD OF EXERCISE OF OPTION. Optionee shall notify the Company by
written notice, in the form of the Notice of Exercise attached hereto
(Attachment A), delivered to the Company's principal office, attention: Chief
Financial Officer. At the Optionee's option, the payment for the Shares may be
made either by Optionee's check payable to the order to the Company in full
payment for the total exercise price of the number of Shares purchased or by
execution and delivery by the Optionee to the Company of a Note(s), in similar
form and content as Notes previously used by the Company for similar purposes
("Note(s)"), dated as of each Notice of Exercise. As soon as practicable after
the receipt of such Notice of Exercise and accompanying payment for the purchase
of Shares, the Company shall, at its principal office, tender to Optionee a
certificate or certificates issued in Optionee's name evidencing the Shares
purchased by Optionee hereunder.

         6. TERMINATION OF OPTION. To the extent exercisable but not exercised,
the Option shall terminate upon the first to occur of the following dates:

             (a) October 5, 2003

             (b) the expiration of ninety (90) days following the date
Optionee's employment terminates with the Company and/or any of its subsidiaries
included in the Plan with Cause, as defined in Optionee's Employment Agreement
dated March 1, 1999.

Subject to the provisions of this paragraph, in the event of Optionee's death,
the exercisable but unexercised portion of the Option may be exercised by the
estate of Optionee, or by the person who acquired the right to exercise the
Option by bequest or inheritance or by reason of the death of Optionee.

In the event of Employee's termination without Cause, all granted but
unexercised Options shall continue to be fully exercisable in accordance with
the provisions herein. Additionally, in the event this Agreement is not renewed
at the end of the Employment Term, then all granted but unexercised Options
shall continue to be fully exercisable in accordance with the provisions herein.

         7. PLEDGE OF SHARES. If payment for the purchase of Shares under this
Option is made through execution and delivery of a Note(s), effective upon
Optionee's purchase(s) of the Shares and the delivery of the Note(s), in order
to secure the Company's obligations under the Note(s), Optionee hereby pledges,

                                       2
<PAGE>   3

assigns and sets over to the Company, and grants to the Company a security
interest in, the Shares. The Shares pledged pursuant hereto shall be maintained
in escrow with Atlas, Pearlman, Trop & Borkson, P.A. pursuant to the terms of a
Pledge and Escrow Agreement previously used by the Company for similar purposes,
which shall be executed by Optionee and the Company upon delivery of a Note(s).
As long as any Shares remain subject to the lien of the Pledge, such Shares may
not be further pledged or encumbered in any manner, and shall not be sold,
transferred or otherwise disposed of. The Escrow Agent shall not be required to
relinquish the Pledge or the Escrow Agent's possession of the certificates
evidencing the Shares, unless no later than concurrently with the sale of the
Shares pursuant to an S-8 registration, all Notes which are secured by such
Shares are paid in full. In the event any of the Shares are to be titled in the
name of an immediate family member of Optionee or a trust pursuant to the terms
herein, as a condition thereto the designated title holder(s) of such Shares
shall execute and deliver to the Company a pledge and escrow agreement, in form
and content reasonably satisfactory to the Company and its counsel, consistent
with the terms herein. No transfer of Shares to, or designation by Optionee of
(for the purposes of owning Shares) any person or entity shall relieve Optionee
of any of his obligations under the Note(s) or this Agreement. With respect to
each Note under which a voluntary prepayment is made by Optionee, provided that
interest payments on such Note are current through the date of prepayment and
such Note is not in default and has not been accelerated, for each $5,000 of
principal paid by Optionee under such Note, 10,000 Shares of the Shares pledged
to secure such Note shall be released from the lien of the Pledge. As long as no
event of default has occurred with respect to a Note and no event giving right
to accelerate such Note has occurred, Optionee shall retain all voting rights
with respect to all Shares securing such Note. Following an event of default or
an acceleration event, the Company shall have and may exercise all voting rights
with respect to such Shares. Optionee hereby irrevocably appoints the Company
Optionee's attorney-in-fact for such purpose, it being acknowledged that such
appointment is coupled with an interest. Any dividends or distributions payable
in respect of any Shares subject to the Pledge shall automatically be applied to
pay down the Note(s) in inverse order of their respective maturity date(s). In
the event of a default under any Note, in addition to and not in limitation or
lieu of any other rights or remedies the Company may have against Optionee as a
result of such default, the Company may exercise all of its rights at law and in
equity as a secured party, including without limitation under the Uniform
Commercial Code, with respect to all Shares then securing the Note with respect
to which the default has occurred. Upon a default, without limiting any of the
Company's other rights and remedies, the Company may conduct a public or private
foreclosure sale of the Shares securing the Note with respect to which the
default has occurred. Optionee agrees that 10 days notice to him of any private
sale is fair and reasonable. The Company may be the purchaser at any public
foreclosure sale, and may bid any commercially reasonable amount at such sale.
In all events, in the event of a public or private foreclosure sale, Optionee
shall be liable for any deficiency. All of the Company's rights and remedies
under the Note(s), the Pledge and this Agreement, and at law or in equity, are
cumulative, and none is intended to be in substitution or in lieu of, nor is the
exercise of one intended to be a waiver of, any other. The Company shall have no

                                       3
<PAGE>   4

obligation to proceed against the Shares before proceeding against Optionee with
respect to any default under any of the Notes.

         8. SECURITIES LAWS. Employer represents and warrants that (i) all
shares underlying the Options will be issued from shares authorized by and
subject to the provisions of the Plan; (ii) the Plan and the shares underlying
the Options shall be registered under the applicable regulations of the
Securities and Exchange Commission on Form S-8; and (iii) such registration
covering the shares underlying the Options will be maintained as effective for
the longer of (a) the Employment Term or (b) the Exercise Period of the Options
as defined herein.

         9. ADJUSTMENT OF SHARES. If at any time prior to the expiration or
exercise in full of the Option, there shall be any increase or decrease in the
number of issued and outstanding shares of the Common Stock through the
declaration of a stock dividend or through any recapitalization resulting in a
stock split-up, combination or exchange of the Common Stock, then and in such
event:

             (i) appropriate adjustment shall be made in the maximum number of
Shares available for grant, so that the same percentage of the Company's issued
and outstanding Shares shall continue to be subject to being so optioned; and

             (ii) appropriate adjustment shall be made in the number of Shares,
and the exercise price per Share thereof, that remain unexercised under the
Option, so that the same percentage of the Company's issued and outstanding
shares of Common Stock shall remain subject to purchase at the same aggregate
exercise price.

Except as otherwise expressly provided herein, the issuance by the Company of
shares of its capital stock of any class, or securities convertible into shares
of capital stock of any class, either in connection with a direct sale of upon
the exercise of rights or warrants to subscribe therefore, or upon conversions
of shares or obligations the Company convertible into such shares or other
securities, shall not affect, and no adjustment by reason thereof shall be made
with respect to, the number of exercise price of the Shares that remain
unexercised under the Option.

Without limiting the generality of the foregoing, the existence of unexercised
Shares under the Option shall not affect in any manner the right or power of the
Company to make, authorize or consummate (i) any or all adjustments,
recapitalizations, reorganizations or other changes in the Company's capital
structure or its business; (ii) any merger or consolidation of the Company;
(iii) any issue by the Company of debt securities, or preferred or preference
stock that would rank above the Shares issuable upon exercise of the Option;
(iv) the dissolution or liquidation of the Company; (v) any sale, transfer or
assignment of all or any part of the assets or business of the Company; or (vi)
any other corporate act or proceeding, whether of a similar character or
otherwise.

                                       4
<PAGE>   5

         10. NO RIGHTS AS STOCKHOLDER. Optionee shall have no rights as a
stockholder of the Company in respect of the Shares as to which the Option shall
not have been exercised and payments made therefore as herein provided.

         11. BINDING EFFECT. Except as otherwise provided herein, this Agreement
shall be binding upon and inure to the benefit of the parties hereto, their
heirs, legal representatives, successors and permitted assigns.

         12. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without giving effect to the
conflict of laws principles thereof.

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

                                            VIRAGEN, INC.

                                            By: /s/ Dennis W. Healey
                                                -------------------------------
                                                    Dennis W. Healey
                                                    Executive Vice President/CFO

                                                OPTIONEE

                                                /s/ Gerald Smith
                                                -------------------------------
                                                Gerald Smith

                                       5
<PAGE>   6

                                  ATTACHMENT A

                               NOTICE OF EXERCISE

The undersigned hereby irrevocably elects to exercise the within Option to the
extent of purchasing __________ shares of Common Stock of Viragen, Inc., a
Delaware Corporation, and hereby makes payments of $________ in payment
therefor.

                                            --------------------------
                                            Signature

                                            --------------------------
                                            Date

            INSTRUCTIONS FOR ISSUANCE OF STOCK AND CORPORATE RECORDS

Name:
       ---------------------------------------------------------
                  (Please type or print in block letters)

Address:
       ---------------------------------------------------------

       ---------------------------------------------------------

Social  Security #:
                    --------------------------------------------

Phone #: (    )
          ---- --------------------------------
Fax #:   (    )
          ---- --------------------------------

                                       6

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00010-of-00352.parquet"}]]