AMENDED AND RESTATED

                        1990 INCENTIVE AND NON-INCENTIVE

                                STOCK OPTION PLAN

                                       OF

                           VIMRx PHARMACEUTICALS INC.

             (AS AMENDED JULY 15, 1991, AUGUST 31, 1995 MAY 13, 1996
                              AND FEBRUARY 6, 1997)


         1.       Purpose of Plan.

                  The purpose of this Incentive and  Non-Incentive  Stock Option
Plan ("Plan") is to further the growth and development of VIMRx  Pharmaceuticals
Inc. ("Company") and any subsidiaries thereof by encouraging selected employees,
directors  and other  persons who  contribute  and are  expected  to  contribute
materially  to the  Company's  success to obtain a  proprietary  interest in the
Company through the ownership of stock,  thereby  providing such persons with an
added  incentive to promote the best  interests of the Company and affording the
Company a means of attracting to its service persons of outstanding ability.

         2.       Stock Subject to the Plan.

                  An  aggregate  of  2,400,000  shares of the  Company's  Common
Stock,  $.001 par value  ("Common  Stock")  subject,  however,  to adjustment or
change pursuant to paragraph 12 hereof,  shall be reserved for issuance upon the
exercise of options  which may be granted from time to time in  accordance  with
the Plan  ("Options").  Such shares may be, in whole or in part,  authorized but
unissued shares or issued shares which have been reacquired by the Company.  If,
for any reason,  an Option shall lapse,  expire or terminate without having been
exercised  in full,  the  unpurchased  shares  covered  thereby  shall  again be
available for purposes of the Plan.

         3.       Administration.

                  (a) Except as provided in paragraph (c) below,  the Plan shall
be  administered  by the  Committee.  The Board of Directors  shall  appoint the
Committee  from among its members.  Such  Committee  shall be composed of two or
more Directors who, to the extent  practicable,  shall be "outside directors" as
defined in  regulations  under  Section  162(m) of the Internal  Revenue Code of
1986,  as amended  (the  "Code"),  and  "non-employee  directors"  as defined by
Regulation 240.16b-3 under the Securities Exchange Act of 1934, as amended. Such
Committee  shall have and may exercise any and all of the powers relating to the
administration of the Plan and the grant of Options  thereunder as are set forth
in subparagraph 3(b) hereof as the Board of Directors shall confer and delegate.
The Board of  Directors  shall have power at any time to fill  vacancies  in, to
change the membership of, or to discharge such  Committee.  The Committee  shall
select one of its members as its  chairman  and shall hold its  meetings at such
time and at such places as it shall deem advisable. A majority of such Committee
shall  constitute a quorum and such majority  shall  determine  its action.  Any
action may be taken  without a meeting by written  consent of all the members of
the Committee.  The Committee  shall keep minutes of its  proceedings  and shall
report the same to the Board of Directors at the meeting next succeeding.

                  (b) The Committee  shall  administer the Plan and,  subject to
the  provisions  of the Plan,  shall have sole  authority in its  discretion  to
determine the persons to whom, and the time or times at which,  Options shall be
granted;  the number of shares to be subject to each such Option; the provisions
regarding  exercisability  of each Option;  the expiration  date of each Option;
whether the Option shall contain a "cashless exercise" provision; whether all or
any  portion  of the  Options  shall  be  incentive  stock  options  ("Incentive
Options")  qualifying  under  Section 422A of the Code or stock options which do
not so qualify ("Non-Incentive  Options");  whether a Non-Incentive Option shall
have  limited  transferability  as  permitted  under  the  Plan;  and  whether a
Non-Incentive  Option granted to a non-employee  shall  terminate  following the
non-employee's  termination of engagement in performing services for the Company
or its  subsidiaries  pursuant to Section 9 of the Plan. Both Incentive  Options
and  Non-Incentive  Options  may be granted to the same  person at the same time
provided   each  type  of  Option  is  clearly   designated.   In  making   such
determinations,  the  Committee may take into account the nature of the services
rendered by such  persons,  their  present  and  potential  contribution  to the
Company's success and such other factors as the Committee in its sole discretion
may deem relevant.  Subject to the express provisions of the Plan, the Committee
shall also have authority to interpret the Plan; to prescribe, amend and rescind
rules and regulations relating thereto; to determine the terms and provisions of
the respective  Option  Agreements,  which shall be  substantially  in the forms
attached  hereto  as  Exhibit  A and  Exhibit  B; to  amend  the  provisions  of
outstanding  Options to provide for accelerated  exercisability or the extension
of the  expiration  date of such Options;  and to make all other  determinations
necessary  or  advisable  for  the  administration  of the  Plan,  all of  which
determinations shall be conclusive and not subject to review.

                  (c) The Board of Directors may administer the Plan, in lieu of
and with the same powers as the Committee,  with respect to any Options  granted
or to be granted under the Plan, provided that such administration is consistent
with the provisions of Section 162(m) of the Code.

         4.       Eligibility for Receipt of Options.

                  (a) Incentive  Options.  Incentive Options may be granted only
to employees (including officers) of the Company and/or any of its subsidiaries.
A  director  of the  Company or any  subsidiary  who is not an  employee  of the
Company or of one of its  subsidiaries  is not  eligible  to  receive  Incentive
Options  under the Plan.  Further,  Incentive  Options may not be granted to any
person who, at the time the Incentive Option is granted,  owns (or is considered
as owning  within the meaning of Section  425(d) of the Code)  stock  possessing
more than 10% of the total combined  voting power of all classes of stock of the
Company or any subsidiary (10% Owner),  unless at the time the Incentive  Option
is  granted  to the 10%  Owner,  the  option  price is at least 110% of the fair
market value of the Common Stock subject  thereto and such  Incentive  Option by
its terms is not  exercisable  subsequent  to five years from the date of grant.
The aggregate fair market value  (determined as of the time an Incentive  Option
is granted) of the shares of the Company's  Common Stock  initially  purchasable
upon  exercise of an Incentive  Option  during any calendar  year may not exceed
$100,000.

                  (b)  Non-Incentive  Options.   Non-Incentive  Options  may  be
granted to any employees  (including  employees who have been granted  Incentive
Options),  directors,  consultants,  agents,  independent  contractors and other
persons whom the Board of Directors (or Committee) determines will contribute to
the Company's success.

                  (c) The  maximum  number  of  shares  that may be  subject  to
options  under this Plan  granted  during  any  calendar  year to any  executive
officer of the Company is 800,000 shares.

                  (d) In the event on outstanding  Incentive Option or a portion
thereof no longer  qualifies as an incentive  stock option under Section 422A of
the Code, such Option or portion  thereof,  as applicable,  thereafter  shall be
deemed a Non-Incentive Option under the Plan.

         5.       Option Price.

                  The  purchase  price of the shares of Common  Stock under each
Option  shall be  determined  by the  Committee,  which  determination  shall be
conclusive  and not subject to review,  but in no event shall the purchase price
be less than 100% of the fair  market  value of the Common  Stock on the date of
grant in the case of Incentive Options (110% of fair market value in the case of
Incentive  Options  granted to a 10% Owner) and 50% of the fair market  value of
the Common Stock on the date of the grant in the case of Non-Incentive Options.

                  For  purposes  of the Plan,  unless the  Committee  determines
otherwise,  the "fair  market  value" of a share of Common Stock as of a certain
date shall be the  closing  sale price of the Common  Stock on The Nasdaq  Stock
Market or, if the Common  Stock is not then traded on The Nasdaq  Stock  Market,
such national  securities  exchange on which the Common Stock is then traded, on
the trading  date  immediately  preceding  the date fair  market  value is being
determined.  The  Committee  may make such other  determination  of fair  market
value, based on other factors, as it shall deem appropriate.

                  For purposes of the Plan, the date of grant of an Option shall
be the date on which the  Committee  shall by  resolution  duly  authorize  such
Option.



         6.       Term of Options.

                  The term of each  Option  shall be such number of years as the
Committee shall  determine,  subject to earlier  termination as herein provided,
but in no event more than ten years from the date such Option is granted.

         7.       Exercise of Options.

                  (a) Each Option shall be exercisable to the extent  determined
by the Committee,  but in no event shall an Option be exercisable until at least
six months from the date of grant.

                  (b) An Option may not be exercised  for  fractional  shares of
the Company's Common Stock.

                  (c) Except as provided in paragraphs 9, 10 and 11 hereof,  and
unless  determined  otherwise by the  Committee  with  respect to  Non-Incentive
Options  granted to  non-employees,  no Option shall be  exercisable  unless the
holder  thereof  shall  have  been an  employee,  director,  consultant,  agent,
independent  contractor  or other  person  employed by or engaged in  performing
services for the Company and/or a subsidiary continuously from the date of grant
to the date of exercise.

                  (d) The exercise of an Option shall be contingent upon receipt
from the  holder  thereof of a written  representation  that at the time of such
exercise  it is the  optionee's  then  present  intention  to acquire the Option
shares for investment and not with a view to the  distribution or resale thereof
(unless a Registration  Statement  covering the shares purchasable upon exercise
of the Options shall have been declared effective by the Securities and Exchange
Commission)  and upon  receipt by the Company of cash,  or a check to its order,
for  the  full  purchase  price  of  such  shares.  The  Committee  may,  in its
discretion,  include a "cashless  exercise"  provision in the applicable  Option
Agreement,  in  which  event  the  optionee  will be  permitted  (i) to  deliver
previously  owned  shares of Common  Stock with a fair market value equal to the
exercise price in payment of the full purchase price of such shares,  or (ii) to
request that the Company  withhold shares of Common Stock issuable upon exercise
of such  Option  with a fair market  value  equal to the  exercise  price of the
shares being purchased  under the Option (thereby  reducing the number of shares
issuable upon exercise of the Option).

                  (e) The holder of an Option shall have none of the rights of a
stockholder  with respect to the shares  purchasable upon exercise of the Option
until a  certificate  for such shares  shall have been issued to the holder upon
due exercise of the Option.

                  (f) The proceeds  received by the Company upon  exercise of an
Option shall be added to the  Company's  working  capital and be  available  for
general corporate purposes.

         8.       Transferability of Options.

                  No Option granted  pursuant to the Plan shall be  transferable
otherwise than by will or the laws of descent or distribution  and an Option may
be exercised  during the  lifetime of the holder only by such holder,  provided,
however,  that the Committee may provide for  transferability of a Non-Incentive
Option to an optionee's family members or family trusts.

         9.       Termination of Employment or Engagement.

                  (a) Except as provided in  paragraph  (b) below,  In the event
the  employment of the holder of an Option shall be terminated by the Company or
a subsidiary for any reason other than by reason of death or disability,  or the
engagement  of  a  non-employee  holder  of  a  Non-Incentive  Option  shall  be
terminated  by the  Company or a  subsidiary  for any  reason,  such holder may,
within three months from the date of such  termination,  exercise such Option to
the  extent  such  Option  was  exercisable  by such  holder at the date of such
termination.   Notwithstanding  the  foregoing,   no  Option  may  be  exercised
subsequent  to the date of its  expiration.  Absence  on leave  approved  by the
employer  corporation  shall not be considered an interruption of employment for
any purpose under the Plan. In addition, at the discretion of the Committee, the
exercisability of an outstanding  Non-Incentive Option may be extended to a date
determined by the Committee but not beyond ten years from the date of grant.

                  (b) The Committee may, in its discretion, at the time of grant
or by amending  the  applicable  outstanding  Non-Incentive  Option,  delete the
foregoing  termination  provision with respect to a Non-Incentive Option granted
to a non-employee of the Company or its subsidiaries.

                  (c)  Nothing  in the Plan or in any Option  Agreement  granted
hereunder shall confer upon any Optionholder any right to continue in the employ
of the Company or any  subsidiary  or obligate the Company or any  subsidiary to
continue the  engagement  of any  Optionholder  or interfere in any way with the
right of the Company or any such  subsidiary  to terminate  such  Optionholder's
employment or engagement at any time.

         10.      Disability of Holder of Option.

                  If  the  employment  of  the  holder  of an  Option  shall  be
terminated by reason of such holder's disability, such holder may, within twelve
months  from the date of such  termination,  exercise  such option to the extent
such  Option was  exercisable  by such  holder at the date of such  termination.
Notwithstanding the foregoing, no Option may be exercised subsequent to the date
of its expiration.

         11.      Death of Holder of Option.

                  If the holder of any Option  shall die while in the employ of,
or while performing services for, the Company or one or more of its subsidiaries
(or within six months  following  termination of employment due to  disability),
the Option theretofore granted to such person may be exercised,  but only to the
extent such Option was  exercisable by the holder at the date of death (or, with
respect to employees,  the date of  termination of employment due to disability)
by the legatee or legatees of such person under such  person's  Last Will, or by
such person's personal representative or distributees, within twelve months from
the  date of death  but in no event  subsequent  to the  expiration  date of the
Option.

         12.      Adjustments Upon Changes in Capitalization.

                  If at any time  after  the date of  grant  of an  Option,  the
Company shall by stock  dividend,  split-up,  combination,  reclassification  or
exchange, or through merger or consolidation or otherwise,  change its shares of
Common  Stock  into a  different  number  or kind or  class of  shares  or other
securities or property, then the number of shares covered by such Option and the
price per share thereof shall be proportionately adjusted for any such change by
the Committee whose determination thereon shall be conclusive.

         13.      Acceleration of Exercisability Upon Change in Control.

                  Upon the  occurrence  of a "change in  control" of the Company
(as defined  below),  all  outstanding  Options shall become  immediately  fully
exercisable.  For  purposes  of the Plan,  a "change in  control" of the Company
shall mean (i) the  acquisition  at any time by a "person"  or "group"  (as such
terms are used  Sections  13(d) and 14(d)(2) of the  Exchange Act of  beneficial
ownership  (as  defined in Rule  13d-3  under the  Exchange  Act),  directly  or
indirectly,  of securities representing 50% or more of the combined voting power
in the election of directors of the then  outstanding  securities of the Company
or any successor or the Company;  (ii) the  termination of service of directors,
for any reason  other than death,  disability  or  retirement  from the Board of
Directors,  during any period of two  consecutive  years or less, of individuals
who at the  beginning  of such  period  constituted  a majority  of the Board of
Directors,  unless  the  election  of or  nomination  for  election  of each new
director during such period was approved by a vote of at least two-thirds of the
directors  still in office who were  directors  at the  beginning of the period;
(iii) approval by the stockholders of the Company of any merger,  consolidation,
or  statutory  share  exchange  as a result of which the Common  Stock  shall be
changed,  converted or exchanged  (other than a merger,  consolidation  or share
exchange with a  wholly-owned  Subsidiary)  or liquidation of the Company or any
sale or  disposition  of 80% or more  of the  assets  or  earning  power  or the
Company;  or (iv)  approval  by the  stockholders  of the Company of any merger,
consolidation,  or statutory share exchange to which the Company is a party as a
result of which  the  persons  who were  stockholders  immediately  prior to the
effective  date of the  merger,  consolidation  or  share  exchange  shall  have
beneficial  ownership  of less  than  50% of the  combined  voting  power in the
election of directors of the surviving corporation;  provided,  however, that no
change in control  shall be deemed to have  occurred if, prior to such time as a
change in control  would  otherwise be deemed to have  occurred,  the  Company's
Board of Directors deems otherwise.




<PAGE>



         14.      Vesting of Rights Under Options.


                  Neither  anything  contained in the Plan nor in any resolution
adopted  or to be  adopted  by the  Committee,  the  Board of  Directors  or the
stockholders of the Company shall constitute the vesting of any rights under any
Option.  The vesting of such rights shall take place only when a written  Option
Agreement,  substantially  in the form of the Incentive  Stock Option  Agreement
attached  hereto  as  Exhibit  A or the  Non-Incentive  Stock  Option  Agreement
attached  hereto as Exhibit B, shall be duly  executed  and  delivered by and on
behalf of the Company and the person to whom the Option shall be granted.

         15.      Withholding Taxes.

                  Whenever   under  the  Plan   shares   are  to  be  issued  in
satisfaction  of the exercise of Options granted  thereunder,  the Company shall
have the  right to  require  the  recipient  to remit to the  Company  an amount
sufficient to satisfy  federal,  state and local  withholding  tax  requirements
prior to the delivery of any certificate or certificates for such shares.

         16.      Termination and Amendment.

                  The Plan,  which was adopted by the Board of Directors on July
10, 1990 and approved by the  shareholders  of the Company,  shall  terminate on
July 9, 2000 and no Option shall be granted under the Plan after such date.  The
Board of Directors may at any time prior to such date terminate the Plan or make
such modifications or amendments  thereto as it shall deem advisable,  provided,
however, that shareholder approval shall be required:

          (i)     to increase the number of shares  reserved  for issuance
                  under the Plan;

         (ii)     to materially increase the benefits accruing to participants
                  under the Plan;

        (iii)     to materially modify the requirements of eligibility for
                  participation in the Plan; or

         (iv)     if  otherwise  required  to comply  with the  incentive  stock
                  option  provisions of Section 162(m) of the Code or the listed
                  company  requirements  of  The  Nasdaq  Stock  Market  or of a
                  national securities exchange on which the Common Stock is then
                  traded,

and, provided, further, that no modification or amendment shall adversely affect
the rights of a holder of an Option  previously  granted  under the Plan without
such holder's written consent.



<PAGE>







                                                          5

                                                                 EXHIBIT A

                           VIMRx PHARMACEUTICALS INC.

                        INCENTIVE STOCK OPTION AGREEMENT

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

To:

                  We are  pleased  to notify  you that by the  determination  of
theStock  Option Plan  Committee  (hereinafter  the  "Committee")  an  incentive
stockoption   to  purchase   ______   shares  of  the  Common   Stock  of  VIMRx
Pharmaceuticals  Inc.(herein  called the  "Company")  at a price of $______  per
share has this ____ day  of___________been  granted  to you under the  Company's
1990 Incentive and  Non-Incentive  Stock Option Plan (herein called the "Plan").
This option may be exercised only upon the terms and conditions set forth below.


<PAGE>






                  1.        Purpose of Option.

                  The  purpose of the Plan  under  which  this  incentive  stock
option has been granted is to further the growth and  development of the Company
and its  subsidiaries  by  encouraging  key employees,  directors,  consultants,
agents,  independent  contractors  and  other  persons  who  contribute  and are
expected  to  contribute  materially  to  the  Company's  success  to  obtain  a
proprietary  interest in the Company  through the  ownership  of stock,  thereby
providing such persons with an added  incentive to promote the best interests of
the Company,  and  affording  the Company a means of  attracting  to its service
persons of outstanding ability.


                  2.       Acceptance of Option Agreement.

                  Your execution of this incentive  stock option  agreement will
indicate your  acceptance of and your  willingness to be bound by its terms;  it
imposes no  obligation  upon you to purchase  any of the shares  subject to this
option.  Your obligation to purchase shares can arise only upon your exercise of
the option in the manner set forth in paragraph 4 hereof.


                  3.       When Option May Be Exercised.

                  (a) The option  granted you hereunder may not be exercised for
a period of six months from the date of its grant by the  Committee as set forth
above. Thereafter, this option shall be exercisable as follows:


                  [Insert exercisability provisions. A typical example, although
                   not required under the  Plan, is as follows:]

                           [(i)             at the end of one year from the date
                                            of  grant,  up to 25% of the total
                                            shares subject to the option;

                           (ii)             at the end of the second year from
                                            the date of grant, up to 50%;

                           (iii)            at the end of the third year from
                                            the date of grant, up to 75%;

                           (iv)             at the end of the fourth year from
                                            the date of grant, up to 100%.]

This  option may not be  exercised  for less than ten shares at any one time (or
the remaining  shares then  purchasable if less than ten) and expires at the end
of  ________  years  [insert  number of years;  maximum up ten] from the date of
grant  whether  or not it has been  duly  exercised  (hereinafter,  the  "Option
Expiration Date"),  unless sooner terminated as provided in paragraphs 5, 6 or 7
hereof.


                  4.       How Option May Be Exercised.

                  This option is  exercisable  by a written notice signed by you
and delivered to the Company at its executive offices,  signifying your election
to  exercise  the  option.  The notice must state the number of shares of Common
Stock as to which your option is being  exercised,  must  contain a statement by
you (in a form acceptable to the Company) that such shares are being acquired by
you for investment and not with a view to their distribution or resale (unless a
Registration  Statement  covering  the  shares  purchasable  has  been  declared
effective by the Securities and Exchange  Commission) and must be accompanied by
cash or a check to the order of the Company for the full  purchase  price of the
shares being purchased [if "cashless  exercise" is permitted,  add the following
phrase:]  [, unless  exercised  pursuant to the  following  "cashless  exercise"
provision.]

         [Insert the following "cashless exercise" provision,  if granted by the
Committee:] [In lieu of paying for the shares  purchasable  under this option by
cash or check, you may (i) deliver  previously owned shares of Common Stock with
a fair  market  value  equal to the full  purchase  price  of the  shares  being
purchased under this option, or (ii) request that the Company withhold shares of
Common  Stock  issuable  upon  exercise of this option with a fair market  value
equal to the full purchase price of the shares being purchased under this option
(thereby  reducing the number of shares  issuable upon exercise of this option).
For purposes of this option,  unless the  Committee  determines  otherwise,  the
"fair market value" of a share of Common Stock as of a certain date shall be the
closing  sale price of the Common  Stock on The Nasdaq  Stock  Market or, if the
Common  Stock is not then  traded on The  Nasdaq  Stock  Market,  such  national
securities  exchange on which the Common  Stock is then  traded,  on the trading
date immediately  preceding the date fair market value is being determined.  The
Committee may make such other determination of fair market value, based on other
factors, as it shall deem appropriate.]

                  If notice of the  exercise of this option is given by a person
or persons  other than you,  the Company  may  require,  as a  condition  to the
exercise of this option,  the submission to the Company of appropriate  proof of
the right of such person or persons to exercise this option.

                  Certificates  for shares of the Common Stock so purchased will
be issued as soon as practicable. The Company, however, shall not be required to
issue or deliver a  certificate  for any shares until it has  complied  with all
requirements of the Securities Act of 1933, the Securities Exchange Act of 1934,
any stock  exchange on which the  Company's  Common Stock may then be listed and
all applicable state laws in connection with the issuance or sale of such shares
or the  listing  of such  shares on said  exchange.  Until the  issuance  of the
certification  for such  shares,  you or such other person as may be entitled to
exercise this option shall have none of the rights of a stockholder with respect
to shares subject to this option.

                  The Company shall have the right to require you, or such other
person as may be permitted to exercise  this option,  to remit to the Company an
amount   sufficient  to  satisfy  federal,   state  and  local  withholding  tax
requirements prior to the delivery of any certificate or certificates for shares
of Common Stock issuable upon exercise of this option.

                  5.       Termination of Employment.

                  If your employment with the Company (or a subsidiary  thereof)
is  terminated  for any  reason  other  than by  death  or  disability,  you may
exercise, within three months from the date of such termination, that portion of
the  option  which  was  exercisable  by you at the  date of  such  termination,
provided, however, that such exercise occurs no later than the Option Expiration
Date.

                  6.       Disability.

                  If your employment with the Company (or a subsidiary  thereof)
is terminated  by reason of your  disability,  you may  exercise,  within twelve
months from the date of such termination,  that portion of this option which was
exercisable by you at the date of such termination, provided, however, that such
exercise occurs no later than the Option Expiration Date.

                  7.       Death.

                  If you die while  employed  by the  Company  (or a  subsidiary
thereof)  or within six  months  after  termination  of your  employment  due to
disability, that portion of this option which was exercisable by you at the date
of your death may be exercised by your legatee or legatees  under your Will,  or
by your personal representatives or distributees,  within twelve months from the
date of your death, but in no event after the Option Expiration Date.

                  8.       Non-Transferability of Option.

                  This option  shall not be  transferable  except by Will or the
laws of descent and distribution, and may be exercised during your lifetime only
by you.

                  9.       Adjustments upon Changes in Capitalization.

                  If at any time  after  the date of grant of this  option,  the
Company shall, by stock dividend,  split-up,  combination,  reclassification  or
exchange, or through merger or consolidation, or otherwise, change its shares of
Common  Stock  into a  different  number  or kind or  class of  shares  or other
securities or property, then the number of shares covered by this option and the
price of each such share shall be  proportionately  adjusted for any such change
by the Committee, whose determination shall be conclusive.

                  10.     Acceleration of Exercisability Upon Change in Control.

                  Upon the  occurrence  of a "change in  control" of the Company
(as defined below), this option shall become immediately fully exercisable.  For
purposes of this option, a "change in control" of the Company shall mean (i) the
acquisition  at any  time by a  "person"  or  "group"  (as such  terms  are used
Sections  13(d) and  14(d)(2) of the Exchange Act of  beneficial  ownership  (as
defined in Rule 13d-3  under the  Exchange  Act),  directly  or  indirectly,  of
securities representing 50% or more of the combined voting power in the election
of directors of the then outstanding  securities of the Company or any successor
or the Company;  (ii) the  termination  of service of directors,  for any reason
other than death,  disability or retirement from the Board of Directors,  during
any period of two consecutive years or less, of individuals who at the beginning
of such  period  constituted  a majority of the Board of  Directors,  unless the
election of or nomination  for election of each new director  during such period
was approved by a vote of at least  two-thirds of the directors  still in office
who were  directors  at the  beginning  of the  period;  (iii)  approval  by the
stockholders  of the Company of any merger,  consolidation,  or statutory  share
exchange as a result of which the Common  Stock shall be changed,  converted  or
exchanged  (other  than  a  merger,  consolidation  or  share  exchange  with  a
wholly-owned   Subsidiary)  or  liquidation  of  the  Company  or  any  sale  or
disposition  of 80% or more of the assets or earning  power or the  Company;  or
(iv) approval by the  stockholders of the Company of any merger,  consolidation,
or statutory share exchange to which the Company is a party as a result of which
the persons who were stockholders immediately prior to the effective date of the
merger,  consolidation or share exchange shall have beneficial ownership of less
than 50% of the  combined  voting  power in the  election  of  directors  of the
surviving  corporation;  provided,  however,  that no change in control shall be
deemed to have  occurred  if,  prior to such time as a change in  control  would
otherwise be deemed to have  occurred,  the Company's  Board of Directors  deems
otherwise.
                  11.      Subject to Terms of the Plan.

                  This incentive stock option  agreement shall be subject in all
respects  to the  terms  and  conditions  of the  Plan  and in the  event of any
question or  controversy  relating to the terms of the Plan, the decision of the
Committee shall be conclusive.

                                                     Sincerely yours,

                                                     VIMRx PHARMACEUTICALS INC.



                                                     By:
                                                        Name:
                                                        Title:


Agreed to and accepted this
_____ day of ________, 199 .


_____________________
Signature of Optionee


<PAGE>







                                        5

                           VIMRx PHARMACEUTICALS INC.

                      NON-INCENTIVE STOCK OPTION AGREEMENT

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

To:

                  We are pleased to notify you that by the  determination of the
Stock Option Plan  Committee  (herein called the  "Committee")  a  non-incentive
stock  option  to  purchase   ______   shares  of  the  Common  Stock  of  VIMRx
Pharmaceuticals  Inc.  (herein  called the  "Company")  at a price of $ ____ per
share  has this day of _____  been  granted  to you  under  the  Company's  1990
Incentive and Non-Incentive  Stock Option Plan (herein called the "Plan").  This
option may be exercised only upon the terms and conditions set forth below.



<PAGE>





                  1.       Purpose of Option.

                  The purpose of the Plan under which this  non-incentive  stock
option has been granted is to further the growth and  development of the Company
and its  subsidiaries  by  encouraging  key employees,  directors,  consultants,
agents,  independent  contractors  and  other  persons  who  contribute  and are
expected  to  contribute  materially  to  the  Company's  success  to  obtain  a
proprietary  interest in the Company  through the  ownership  of stock,  thereby
providing such persons with an added  incentive to promote the best interests of
the Company,  and  affording  the Company a means of  attracting  to its service
persons of outstanding ability.


                  2.       Acceptance of Option Agreement.

                  Your execution of this  non-incentive  stock option  agreement
will indicate your acceptance of and your  willingness to be bound by its terms;
it imposes no obligation  upon you to purchase any of the shares subject to this
option.  Your obligation to purchase shares can arise only upon your exercise of
the option in the manner set forth in paragraph 4 hereof.


                  3.       When Option May Be Exercised.

                  The option  granted  you  hereunder  shall be  exercisable  as
follows:  [set forth terms and expiration date of Option,  but in no event shall
the Option be exercisable until at least six months from the date of grant].

                  This option may not be  exercised  for less than ten shares at
any one time (or the  remaining  shares then  purchasable  if less than ten) and
expires at the end of ________  years [insert  number of years;  maximum up ten]
from the date of grant whether or not it has been duly  exercised  (hereinafter,
the  "Option  Expiration  Date"),   unless  sooner  terminated  as  provided  in
paragraphs 5, 6 or 7 hereof.


                  4.       How Option May Be Exercised.

                  This option is  exercisable  by a written notice signed by you
and delivered to the Company at its executive offices,  signifying your election
to  exercise  the  option.  The notice must state the number of shares of Common
Stock as to which your option is being  exercised,  must  contain a statement by
you (in a form acceptable to the Company) that such shares are being acquired by
you for investment and not with a view to their distribution or resale (unless a
Registration Statement covering the shares purchased has been declared effective
by the Securities and Exchange  Commission) and must be accompanied by cash or a
check to the order of the  Company  for the full  purchase  price of the  shares
being purchased, plus such amount, if any, as is required for withholding taxes.
[If   "cashless   exercise"   is   permitted,   add   the   following   phrase:]
[Notwithstanding  the foregoing,  this option may also be exercised  pursuant to
the following "cashless exercise" provision.]

         [Insert the following "cashless exercise" provision,  if granted by the
Committee:] [In lieu of paying for the shares  purchasable  under this option by
cash or check, you may (i) deliver  previously owned shares of Common Stock with
a fair  market  value  equal to the full  purchase  price  of the  shares  being
purchased under this option, or (ii) request that the Company withhold shares of
Common  Stock  issuable  upon  exercise of this option with a fair market  value
equal to the full purchase price of the shares being purchased under this option
(thereby  reducing the number of shares  issuable upon exercise of this option).
For purposes of this option,  unless the  Committee  determines  otherwise,  the
"fair market value" of a share of Common Stock as of a certain date shall be the
closing  sale price of the Common  Stock on The Nasdaq  Stock  Market or, if the
Common  Stock is not then  traded on The  Nasdaq  Stock  Market,  such  national
securities  exchange on which the Common  Stock is then  traded,  on the trading
date immediately  preceding the date fair market value is being determined.  The
Committee may make such other determination of fair market value, based on other
factors, as it shall deem appropriate.] .
                  If notice of the  exercise of this option is given by a person
or persons  other than you,  the Company  may  require,  as a  condition  to the
exercise of this option,  the submission to the Company of appropriate  proof of
the right of such person or persons to exercise this option.

                  Certificates  for shares of the Common Stock so purchased will
be issued as soon as practicable. The Company, however, shall not be required to
issue or deliver a  certificate  for any shares until it has  complied  with all
requirements of the Securities Act of 1933, the Securities Exchange Act of 1934,
any stock  exchange on which the  Company's  Common Stock may then be listed and
all applicable state laws in connection with the issuance or sale of such shares
or the  listing  of such  shares on said  exchange.  Until the  issuance  of the
certificate  for such  shares,  you or such other  person as may be  entitled to
exercise this option shall have none of the rights of a stockholder with respect
to shares subject to this option.

                  The Company shall have the right to require you, or such other
person as may be permitted to exercise  this option,  to remit to the Company an
amount   sufficient  to  satisfy  federal,   state  and  local  withholding  tax
requirements prior to the delivery of any certificate or certificates for shares
of Common Stock issuable upon exercise of this option.

                  5.        Termination of Employment or Engagement.

                  [The Committee may determine to delete this provision,  at the
time of grant or by  amendment,  to  non-employees,  in which  event  the  words
"Intentionally omitted" should be inserted.] If your employment with the Company
(or a subsidiary  thereof) is  terminated  for any reason other than by death or
disability,  or if a you are not an employee of the Company and your  engagement
by the Company (or a subsidiary) is terminated for any reason, you may exercise,
within  three  months from the date of such  termination,  that  portion of this
option which was exercisable by you at the date of such  termination,  provided,
however, that such exercise occurs prior to the Option Expiration Date.

                  6.       Disability.

                  If your employment with the Company (or a subsidiary  thereof)
is terminated  by reason of your  disability,  you may  exercise,  within twelve
months from the date of such termination,  that portion of this option which was
exercisable by you at the date of such termination, provided, however, that such
exercise occurs prior to the Option Expiration Date.

                  7.       Death.

                  If you die while  employed  by the  Company  (or a  subsidiary
thereof)  or within six  months  after  termination  of your  employment  due to
disability, that portion of this option which was exercisable by you at the date
of your death may be exercised by your legatee or legatees  under your Will,  or
by your personal representatives or distributees,  within twelve months from the
date of your death, but in no event after the Option Expiration Date.

                  8.       Non-Transferability of Option.

                  This option  shall not be  transferable  except by Will or the
laws of descent and distribution, and may be exercised during your lifetime only
by you.

[Alternative Section 8, if provided for by the Committee:]

                  [8.      Limited Transferability of Option.

                  This  option  shall not be  transferable  except to members of
your family or to your family  trust(s),  and by Will or the laws of descent and
distribution.]

                  9.       Adjustments upon Changes in Capitalization.

                  If at any time  after  the date of grant of this  option,  the
Company shall, by stock dividend,  split-up,  combination,  reclassification  or
exchange, or through merger or consolidation, or otherwise, change its shares of
Common  Stock  into a  different  number  or kind or  class of  shares  or other
securities or property, then the number of shares covered by this option and the
price of each such share shall be  proportionately  adjusted for any such change
by the Committee, whose determination shall be conclusive.

                  10.     Acceleration of Exercisability Upon Change in Control.

                  Upon the  occurrence  of a "change in  control" of the Company
(as defined below), this option shall become immediately fully exercisable.  For
purposes of this option, a "change in control" of the Company shall mean (i) the
acquisition  at any  time by a  "person"  or  "group"  (as such  terms  are used
Sections  13(d) and  14(d)(2) of the Exchange Act of  beneficial  ownership  (as
defined in Rule 13d-3  under the  Exchange  Act),  directly  or  indirectly,  of
securities representing 50% or more of the combined voting power in the election
of directors of the then outstanding  securities of the Company or any successor
or the Company;  (ii) the  termination  of service of directors,  for any reason
other than death,  disability or retirement from the Board of Directors,  during
any period of two consecutive years or less, of individuals who at the beginning
of such  period  constituted  a majority of the Board of  Directors,  unless the
election of or nomination  for election of each new director  during such period
was approved by a vote of at least  two-thirds of the directors  still in office
who were  directors  at the  beginning  of the  period;  (iii)  approval  by the
stockholders  of the Company of any merger,  consolidation,  or statutory  share
exchange as a result of which the Common  Stock shall be changed,  converted  or
exchanged  (other  than  a  merger,  consolidation  or  share  exchange  with  a
wholly-owned   Subsidiary)  or  liquidation  of  the  Company  or  any  sale  or
disposition  of 80% or more of the assets or earning  power or the  Company;  or
(iv) approval by the  stockholders of the Company of any merger,  consolidation,
or statutory share exchange to which the Company is a party as a result of which
the persons who were stockholders immediately prior to the effective date of the
merger,  consolidation or share exchange shall have beneficial ownership of less
than 50% of the  combined  voting  power in the  election  of  directors  of the
surviving  corporation;  provided,  however,  that no change in control shall be
deemed to have  occurred  if,  prior to such time as a change in  control  would
otherwise be deemed to have  occurred,  the Company's  Board of Directors  deems
otherwise.

                  11.      Subject to Terms of the Plan.

                  This non-incentive  stock option agreement shall be subject in
all  respects  to the terms and  conditions  of the Plan and in the event of any
question or  controversy  relating to the terms of the Plan, the decision of the
Committee shall be conclusive.

                  12.      Tax Status.

                  This option does not qualify as an  "incentive  stock  option"
under the  provisions  of Section 422A of the Internal  Revenue Code of 1986, as
amended,  and the income tax  implications  of your  receipt of a  non-incentive
stock option and your exercise of such an option  should be discussed  with your
tax counsel.

                                                     Sincerely yours,

                                                 VIMRx PHARMACEUTICALS INC.


                                                 By:_______________________
                                                   Name:___________________
                                                   Title:__________________

Agreed to and accepted this
____ day of _______ , 199 .


_____________________
Signature of Optionee