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                                  UNIVEC, INC.
                             1998 STOCK OPTION PLAN



1.  PURPOSE.

         The UNIVEC, INC. 1998 STOCK OPTION PLAN (the "Plan") is intended to
provide the employees, directors, independent contractors and consultants of
Univec, Inc. (the "Company") and/or any subsidiary or parent thereof with an
added incentive to commence and/or continue their services to the Company and to
induce them to exert their maximum efforts toward the Company's success. By thus
encouraging employees, directors, independent contractors and consultants and
promoting their continued association with the Company, the Plan may be expected
to benefit the Company and its stockholders. The Plan allows the Company to
grant Incentive Stock Options ("ISOs") (as defined in Section 422(b) of the
Internal Revenue Code of 1986, as amended (the "Code"), Non-Qualified Stock
Options ("NQSOs") not intended to qualify under Section 422(b) of the Code and
Stock Appreciation Rights ("SARs") (collectively the "Options"). The vesting of
one or more Options granted hereunder may be based on the attainment of
specified performance goals of the participant or the performance of the
Company, one or more subsidiaries, parent and/or division of one or more of the
above.

2.  SHARES SUBJECT TO THE PLAN.

         The total number of shares of Common Stock of the Company, $0.001 par
value per share, that may be subject to Options granted under the Plan shall be
300,000 in the aggregate, subject to adjustment as provided in Paragraph 8 of
the Plan; however, the grant of an ISO to an employee together with a tandem SAR
or any NQSO to an employee together with a tandem SAR shall only require one
share of Common Stock available subject to the Plan to satisfy such joint
Option. The Company shall at all times while the Plan is in force reserve such
number of shares of Common Stock as will be sufficient to satisfy the
requirement of outstanding Options granted under the Plan. In the event any
Option granted under the Plan shall expire or terminate for any reason without
having been exercised in full or shall cease for any reason to be exercisable in
whole or in part, the unpurchased shares subject thereto shall again be
available for granting of Options under the Plan.

3.  ELIGIBILITY.

         ISO's or ISO's in tandem with SAR's (provided the SAR meets the
requirements set forth in Temp. Reg. Section 14a.422A-1, A-39 (a) through (e)
inclusive) may be granted from time to time under the Plan to one or more
employees of the Company or of a "subsidiary" or "parent" of the Company, as the
quoted terms are defined within Section 424 of the Code. An Officer is an
employee for the above purposes. However, a director of the Company who is not
otherwise an employee is not deemed an employee for such purposes. NQSOs and
NQSO's in tandem with SARs may be granted from time to time under the Plan to
one or more employees of the Company, Officers, members of the Board of
Directors, independent contractors, consultants and other individuals who are
not employees of, but are involved in the continuing development and success


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of the Company and/or of a subsidiary of the Company, including persons who have
previously been granted Options under the Plan.

4.  ADMINISTRATION OF THE PLAN.

         (a) The Plan shall be administered by the Board of Directors of the
Company as such Board of Directors may be composed from time to time and/or by a
Stock Option Committee or Compensation Committee (the "Committee") which shall
be comprised of solely of at least two Outside Directors (as such term is
defined in regulations promulgated from time to time with respect to Section
162(m)(4)(C)(i) of the Code) appointed by such Board of Directors of the
Company. As and to the extent authorized by the Board of Directors of the
Company, the Committee may exercise the power and authority vested in the Board
of Directors under the Plan. Within the limits of the express provisions of the
Plan, the Board of Directors or Committee shall have the authority, in its
discretion, to determine the individuals to whom, and the time or times at
which, Options shall be granted, the character of such Options (whether ISOs,
NQSOs, and/or SARs in tandem with NQSOs, and/or SARs in tandem with ISOs) and
the number of shares of Common Stock to be subject to each Option, the manner
and form in which the optionee can tender payment upon the exercise of his
Option, and to interpret the Plan, to prescribe, amend and rescind rules and
regulations relating to the Plan, to determine the terms and provisions of
Option agreements that may be entered into in connection with Options (which
need not be identical), subject to the limitation that agreements granting ISOs
must be consistent with the requirements for the ISOs being qualified as
"incentive stock options" as provided in Section 422 of the Code, and to make
all other determinations and take all other actions necessary or advisable for
the administration of the Plan. In making such determinations, the Board of
Directors and/or the Committee may take into account the nature of the services
rendered by such individuals, their present and potential contributions to the
Company's success, and such other factors as the Board of Directors and/or the
Committee, in its discretion, shall deem relevant. The Board of Directors'
and/or the Committee's determinations on the matters referred to in this
Paragraph shall be conclusive.

         (b) Notwithstanding anything contained herein to the contrary, at any
time during the period the Company's Common Stock is registered pursuant to
Section 12 of the Securities Exchange Act of 1934 (the "1934 Act"), the
Committee, if one has been appointed to administer all or part of the Plan,
shall have the exclusive right to grant Options to Covered Employees, as defined
under Section 162(m)(3) of the Code (generally persons subject to Section 16 of
the 1934 Act) and set forth the terms and conditions thereof. With respect to
persons subject to Section 16 of the 1934 Act, transactions under the Plan are
intended, to the extent possible, to comply with all applicable conditions of
Rule 16b-3, as amended from time to time, (and its successor provisions) if any,
under the 1934 Act and Section 162(m)(4)(C) of the Code of 1986, as amended. To
the extent any provision of the Plan or action by the Board of Directors or
Committee fails to so comply, it shall be deemed null and void, to the extent
permitted by law and deemed advisable by the Board of Directors and/or such
Committee.



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5.  TERMS OF OPTIONS.

         Within the limits of the express provisions of the Plan, the Board of
Directors or the Committee may grant either ISOs or NQSOs or SARs in tandem with
NQSOs or SARs in tandem with ISOs. An ISO or an NQSO enables the optionee to
purchase from the Company, at any time during a specified exercise period, a
specified number of shares of Common Stock at a specified price (the "Option
Price"). The optionee, if granted a SAR in tandem with a NQSO or ISO, may
receive from the Company, in lieu of exercising his option to purchase shares
pursuant to his NQSO or ISO, at one of the certain specified times during the
exercise period of the NQSO or ISO as set by the Board of Directors or the
Committee, the excess of the fair market value upon such exercise (as determined
in accordance with subparagraph (b) of this Paragraph 5) of one share of Common
Stock over the Option Price per share specified upon grant of the NQSO or
ISO/SAR multiplied by the number of shares of Common Stock covered by the SAR so
exercised. The character and terms of each Option granted under the Plan shall
be determined by the Board of Directors and/or the Committee consistent with the
provisions of the Plan, including the following:

         (a) An Option granted under the Plan must be granted within 10 years
from the date the Plan is adopted, or the date the Plan is approved by the
stockholders of the Company, whichever is earlier.

         (b) The Option Price of the shares of Common Stock subject to each ISO
and each SAR issued in tandem with an ISO shall not be less than the fair market
value of the Common Stock at the time such ISO is granted. Such fair market
value shall be determined by the Board of Directors and, if the Common Stock is
listed on a national securities exchange or quoted on The Nasdaq Stock Market,
Inc. ("Nasdaq"), the fair market value shall be the closing price of the Common
Stock on such exchange or Nasdaq, or if closing prices are not available or the
Common Stock is quoted on the National Association of Securities Dealers, Inc.
("NASD") OTC Bulletin Board (the "OTC Bulletin Board") or otherwise traded in
the over-the-counter market, the fair market value shall be the mean of the
closing bid and asked prices of the Common Stock, as reported by Nasdaq, the
NASD, the OTC Bulletin Board or the National Quotation Bureau, Inc., as the case
may be, on the day on which the Option is granted or, if there is no closing
price or bid or asked price on that day, the closing price or mean of the
closing bid and asked prices on the most recent day preceding the day on which
the Option is granted for which such prices are available. If an ISO or SAR in
tandem with an ISO is granted to any individual who, immediately before the ISO
is to be granted, owns (directly or through attribution) more than 10% of the
total combined voting power of all classes of capital stock of the Company or a
subsidiary or parent of the Company, the Option Price of the shares of Common
Stock subject to such ISO shall not be less than 110% of the fair market value
per share of the shares of Common Stock at the time such ISO is granted.

         (c) The Option Price of the shares of Common Stock subject to an NQSO
or an SAR in tandem with a NQSO granted pursuant to the Plan shall be determined
by the Board of Directors or the Committee, in its sole discretion, but in no
event less than 85% of the fair market value per share of the shares of Common
Stock at the time of grant.

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         (d) In no event shall any Option granted under the Plan have an
expiration date later than 10 years from the date of its grant, and all Options
granted under the Plan shall be subject to earlier termination as expressly
provided in Paragraph 6 hereof. If an ISO or an SAR in tandem with an ISO is
granted to any individual who, immediately before the ISO is granted, owns
(directly or through attribution) more that 10% of the total combined voting
power of all classes of capital stock of the Company or of a subsidiary or
parent of the Company, such ISO shall by its terms expire and shall not be
exercisable after the expiration of five (5) years from the date of its grant.

         (e) An SAR may be exercised at any time during the exercise period of
the ISO or NQSO with which it is granted in tandem and prior to the exercise of
such ISO or NQSO. Notwithstanding the foregoing, the Board of Directors and/or
the Committee shall in their discretion determine from time to time the terms
and conditions of SAR's to be granted, which terms may vary from the
afore-described conditions, and which terms shall be set forth in a written
stock option agreement evidencing the SAR granted in tandem with the ISO or
NQSO. The exercise of an SAR granted in tandem with an ISO or NQSO shall be
deemed to cancel such number of shares subject to the unexercised Option as were
subject to the exercised SAR. The Board of Directors or the Committee has the
discretion to alter the terms of the SARS if necessary to comply with Federal or
state securities law. Amounts to be paid by the Company in connection with an
SAR may, in the Board of Director's or the Committee's discretion, be made in
cash, Common Stock or a combination thereof.

         (f) An Option granted under the Plan shall become exercisable, in whole
at any time or in part from time to time, but in no event may an Option (i) be
exercised as to less than one hundred (100) shares of Common Stock at any one
time, or the remaining shares of Common Stock covered by the Option if less than
one hundred (100), and (ii) except with respect to performance based Options,
become fully exercisable more than five years from the date of its grant nor
shall less than 20% of the Option become exercisable by the end of any of the
first five years of the Option, determined on an aggregate basis, if not
terminated as provided in Paragraph 6 hereof. The Board of Directors or the
Committee, if applicable, shall, in the event it so elects in its sole
discretion, set one or more performance standards with respect to one or more
Options upon which vesting is conditioned (which performance standards may vary
among the Options).

         (g) An Option granted under the Plan shall be exercised by the delivery
by the holder thereof to the Company at its principal office (to the attention
of the Secretary) of written notice of the number of full shares of Common Stock
with respect to which the Option is being exercised, accompanied by payment in
full, which payment at the option of the optionee shall be in the form of (i)
cash or certified or bank check payable to the order of the Company, of the
Option Price of such shares of Common Stock, or, (ii) if permitted by the
Committee or the Board of Directors, as determined by the Committee or the Board
of Directors in its sole discretion at the time of the grant of the Option with
respect to an ISO and at or prior to the time of exercise with respect to a
NQSO, by the delivery of shares of Common Stock having a fair market value equal
to the Option Price or the delivery of an interest-bearing promissory note
having an original principal balance equal to the Option Price and an interest
rate not below the rate which would result in imputed interest under

                                       -4-

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the Code (provided, in order to qualify as an ISO, more than one year shall have
passed since the date of grant and one year from the date of exercise), or (iii)
at the option of the Committee or the Board of Directors, determined by the
Committee or the Board of Directors in its sole discretion at the time of the
grant of the Option with respect to an ISO and at or prior to the time of
exercise with respect to a NQSO, by a combination of cash, promissory note
and/or such shares of Common Stock (subject to the restriction above) held by
the employee that have a fair market value together with such cash and principal
amount of any promissory note that shall equal the Option Price, and, in the
case of any Option at the discretion of the Committee or Board of Directors by
having the Company withhold from the shares of Common Stock to be issued upon
exercise of the Option that number of shares having a fair market value equal to
the exercise price and/or the tax withholding amount due, or otherwise provide
for withholding as set forth in Paragraph 9(c) hereof, or in the event an
employee is granted an ISO or NQSO in tandem with an SAR and desires to exercise
such SAR, such written notice shall so state such intention. To the extent
allowed by applicable Federal and state securities laws, the Option Price may
also be paid in full by a broker-dealer to whom the optionee has submitted an
exercise notice consisting of a fully endorsed Option, or through any other
medium of payment as the Board of Directors and/or the Committee, in its
discretion, shall authorize.

         (h) The holder of an Option shall have none of the rights of a
stockholder with respect to the shares of Common Stock covered by such holder's
Option until such shares of Common Stock shall be issued to such holder upon the
exercise of the Option.

         (i) All Options granted under the Plan shall not be transferable,
except by will or the laws of descent and distribution and may be exercised
during the lifetime of the holder thereof only by the holder. No Option granted
under the Plan shall be subject to execution, attachment or other process.

         (j) The aggregate fair market value, determined as of the time any ISO
or SAR in tandem with an ISO is granted and in the manner provided for by
Subparagraph (b) of this Paragraph 5, of the shares of Common Stock with respect
to which ISOs granted under the Plan are exercisable for the first time during
any calendar year and under incentive stock options qualifying as such in
accordance with Section 422 of the Code granted under any other incentive stock
option plan maintained by the Company or its parent or subsidiary corporations,
shall not exceed $100,000. Any grant of Options in excess of such amount shall
be deemed a grant of a NQSO.

         (k) Notwithstanding anything contained herein to the contrary, an SAR
which was granted in tandem with an ISO shall (i) expire no later than the
expiration of the underlying ISO; (ii) be for no more than 100% of the spread at
the time the SAR is exercised; (iii) only be exercised when the underlying ISO
is eligible to be exercised; and (iv) only be exercisable when there is a
positive spread.


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         (l) In no event shall an employee be granted Options for more than
_______ shares of Common Stock during any calendar year period; provided,
however, that the limitation set forth in this Section 5(1) shall be subject to
adjustment as provided in Section 8 herein.

6.  DEATH OR TERMINATION OF EMPLOYMENT/CONSULTING RELATIONSHIP.

         (a) Except as provided herein, or otherwise determined by the Board of
Directors or the Committee in its sole discretion, upon termination of
employment with the Company voluntarily by the employee or termination of a
consulting relationship with the Company prior to the termination of the term
thereof, a holder of an Option under the Plan may exercise such Options to the
extent such Options were exercisable as of the date of termination at any time
within thirty (30) days after termination, subject to the provisions of
Subparagraph (d) of this Paragraph 6. Except as provided herein, or otherwise
determined by the Board of Directors or the Committee in its sole discretion, if
such employment or consulting relationship shall terminate for any reason other
than death, voluntary termination by the employee or for cause, then such
Options may be exercised at anytime within three (3) months after such
termination. Notwithstanding anything contained herein to the contrary, unless
otherwise determined by the Board of Directors or the Committee in its sole
discretion, any options granted hereunder to an Optionee and then outstanding
shall immediately terminate in the event the Optionee is terminated for cause,
and the other provisions of this Paragraph 6 shall not be applicable thereto.
For purposes of this Paragraph 6, termination for cause shall be deemed the
decision of the Company, in its sole discretion, that Optionee has not
adequately performed the services for which he/she/it was hired.

         (b) If the holder of an Option granted under the Plan dies (i) while
employed by the Company or a subsidiary or parent corporation or while providing
consulting services to the Company or a subsidiary or parent corporation or (ii)
within three (3) months after the termination of such holder's
employment/consulting, such Options may, subject to the provisions of
subparagraph (d) of this Paragraph 6, be exercised by a legatee or legatees of
such Option under such individual's last will or by such individual's personal
representatives or distributees at any time within such time as determined by
the Board of Directors or the Committee in its sole discretion, but in no event
less than six months after the individual's death, to the extent such Options
were exercisable as of the date of death or date of termination of employment,
whichever date is earlier.

         (c) If the holder of an Option under the Plan becomes disabled within
the definition of Section 22(e)(3) of the Code while employed by the Company or
a subsidiary or parent corporation, such Option may, subject to the provisions
of subparagraph (d) of this Paragraph 6, be exercised at any time within six
months after such holder's termination of employment due to the disability.

         (d) Except as otherwise determined by the Board of Directors or the
Committee in its sole discretion, an Option may not be exercised pursuant to
this Paragraph 6 except to the extent that the holder was entitled to exercise
the Option at the time of termination of employment, consulting relationship or
death, and in any event may not be exercised after the original expiration date
of the Option. Notwithstanding anything contained herein which may be to the
contrary, such termination

                                       -6-

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or death prior to vesting shall, unless otherwise determined by the Board of
Directors or Committee, in its sole discretion, be deemed to occur at a time the
holder was not entitled to exercise the Option.

         (e) The Board of Directors or the Committee, in its sole discretion,
may at such time or times as it deems appropriate, if ever, accelerate all or
part of the vesting provisions with respect to one or more outstanding options.
The acceleration of one Option shall not infer that any other Option is or to be
accelerated.

7.  LEAVE OF ABSENCE.

         For the purposes of the Plan, an individual who is on military or sick
leave or other bona fide leave of absence (such as temporary employment by the
Government) shall be considered as remaining in the employ of the Company or of
a subsidiary or parent corporation for ninety (90) days or such longer period as
such individual's right to reemployment is guaranteed either by statute or by
contract.

8.  ADJUSTMENT UPON CHANGES IN CAPITALIZATION.

         (a) In the event that the outstanding shares of Common Stock are
hereafter changed by reason of recapitalization, reclassification, stock
split-up, combination or exchange of shares of Common Stock or the like, or by
the issuance of dividends payable in shares of Common Stock, an appropriate
adjustment shall be made by the Board of Directors, as determined by the Board
of Directors and/or the Committee, in the aggregate number of shares of Common
Stock available under the Plan, in the number of shares of Common Stock issuable
upon exercise of outstanding Options, and the Option Price per share. Subject to
subparagraph (b) of this Paragraph 8, in the event of any consolidation or
merger of the Company with or into another company, or the conveyance of all or
substantially all of the assets of the Company to another company for solely
stock and/or securities, each then outstanding Option shall upon exercise
thereafter entitle the holder thereof to such number of shares of Common Stock
or other securities or property to which a holder of shares of Common Stock of
the Company would have been entitled to upon such consolidation, merger or
conveyance; and in any such case appropriate adjustment, as determined by the
Board of Directors of the Company (or successor entity) shall be made as set
forth above with respect to any future changes in the capitalization of the
Company or its successor entity. In the event of the proposed dissolution or
liquidation of the Company, subject to subparagraph (b) of this Paragraph 8, the
sale of substantially all the assets of the Company for other than stock and/or
securities, all outstanding Options under the Plan will automatically terminate,
unless otherwise provided by the Board of Directors of the Company or any
authorized committee thereof.

         (b) Any Option granted under the Plan, may, at the discretion of the
Board of Directors of the Company and said other corporation, be exchanged for
options to purchase shares of capital stock of another corporation which the
Company, and/or a subsidiary thereof is merged into, consolidated with, or all
or a substantial portion of the property or stock of which is acquired by said
other corporation or separated or reorganized into. The terms, provisions and
benefits to the

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optionee of such substitute option(s) shall in all respects be identical to the
terms, provisions and benefits of optionee under his Option(s) prior to said
substitution. To the extent the above may be inconsistent with Sections
424(a)(1) and (2) of the Code, the above shall be deemed interpreted so as to
comply therewith.

         (c) Any adjustment in the number of shares of Common Stock shall apply
proportionately to only the unexercised portion of the Options granted
hereunder. If fractions of shares of Common Stock would result from any such
adjustment, the adjustment shall be revised to the next higher whole number of
shares of Common Stock.

9. FURTHER CONDITIONS OF EXERCISE.

         (a) Unless the shares of Common Stock issuable upon the exercise of an
Option have been registered with the Securities and Exchange Commission pursuant
to the Securities Act of 1933, as amended, prior to the exercise of the Option,
an optionee must represent in writing to the Company that such shares of Common
Stock are being acquired for investment purposes only and not with a view
towards the further resale or distribution thereof, and must supply to the
Company such other documentation as may be required by the Company, unless in
the opinion of counsel to the Company such representation, agreement or
documentation is not necessary to comply with said Act.

         (b) The Company shall not be obligated to deliver any shares of Common
Stock until they have been listed on each securities exchange (including for
this purpose, the Nasdaq Stock Market, Inc.) on which the shares of Common Stock
may then be listed or until there has been qualification under or compliance
with such state or federal laws, rules or regulations as the Company may deem
applicable.

         (c) The Board of Directors or Committee may make such provisions and
take such steps as it may deem necessary or appropriate for the withholding of
any taxes that the Company is required by any law or regulation of any
governmental authority, whether federal, state or local, domestic or foreign, to
withhold in connection with the exercise of any Option, including, but not
limited to, (i) the withholding of payment of all or any portion of such Option
and/or SAR until the holder reimburses the Company for the amount the Company is
required to withhold with respect to such taxes, or (ii) the canceling of any
number of shares of Common Stock issuable upon exercise of such Option and/or
SAR in an amount sufficient to reimburse the Company for the amount it is
required to so withhold, (iii) the selling of any property contingently credited
by the Company for the purpose of exercising such Option, in order to withhold
or reimburse the Company for the amount it is required to so withhold, or (iv)
withholding the amount due from such employee's wages if the employee is
employed by the Company or any subsidiary thereof.


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10.  TERMINATION, MODIFICATION AND AMENDMENT.

         (a) The Plan (but not Options previously granted under the Plan) shall
terminate ten (10) years from the earliest of the date of its adoption by the
Board of Directors, or the date the Plan is approved by the stockholders of the
Company, or such date of termination, as hereinafter provided, and no Option
shall be granted after termination of the Plan.

         (b) The Plan may from time to time be terminated, modified or amended
by the affirmative vote of the holders of a majority of the outstanding shares
of capital stock of the Company entitled to vote thereon.

         (c) The Board of Directors of the Company may at any time, prior to ten
(10) years from the earlier of the date of the adoption of the Plan by such
Board of Directors or the date the Plan is approved by the stockholders,
terminate the Plan or from time to time make such modifications or amendments of
the Plan as it may deem advisable; provided, however, that the Board of
Directors shall not, without approval by the affirmative vote of the holders of
a majority of the outstanding shares of capital stock of the Company present in
person or by proxy at an Annual or Special Meeting of the Stockholders and
voting thereon, increase (except as provided by Paragraph 8) the maximum number
of shares of Common Stock as to which Options or shares may be granted under the
Plan, or materially change the standards of eligibility under the Plan.

         (d) No termination, modification or amendment of the Plan may adversely
affect the rights under any outstanding Option without the consent of the
individual to whom such Option shall have been previously granted.

11.  EFFECTIVE DATE OF THE PLAN.

         The Plan shall become effective upon adoption by the Board of Directors
of the Company. The Plan shall be subject to approval by the affirmative vote of
the holders of a majority of the outstanding shares of capital stock of the
Company present in person or by proxy at an Annual or Special Meeting of the
Stockholders and voting thereon within one year after adoption of the Plan by
the Board of Directors.


12. NOT A CONTRACT OF EMPLOYMENT OR FOR SERVICES.

         Nothing contained in the Plan or in any option agreement executed
pursuant hereto shall be deemed to confer upon any individual to whom an Option
is or may be granted hereunder any right to remain in the employ of or be
engaged by the Company or of a subsidiary or parent of the Company or in any way
limit the right of the Company, or of any parent or subsidiary thereof, to
terminate the employment of any employee or engagement of any consultant.





                                       -9-

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13.  OTHER COMPENSATION PLANS.

         The adoption of the Plan shall not affect any other stock option plan,
incentive plan or any other compensation plan in effect for the Company, nor
shall the Plan preclude the Company from establishing any other form of stock
option plan, incentive plan or any other compensation plan.

14.  DISTRIBUTION OF FINANCIAL STATEMENTS.

         The Company shall provide copies of the Company's annual financial
statements for its most recently completed fiscal year to each person granted or
exercising an option pursuant to the Plan as long as that person continues to
hold such options or shares. The Company shall not be required to provide such
financial statements to key employees whose duties in connection with the
Company assure their access to equivalent information.

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