Exhibit 10

                               IMMUNOMEDICS, INC.

                             1992 STOCK OPTION PLAN
                                  (as amended)

     1.  Purpose  of Plan.  The  purpose of this 1992  Stock  Option  Plan is to
promote the interests of Immunomedics,  Inc. and its stockholders by encouraging
employees,  consultants, members of the Corporation's Scientific Advisory Board,
if any,  and  members  of the  Corporation's  Board of  Directors  to  acquire a
proprietary  interest  in  the  Corporation,  thereby  increasing  the  personal
interest  and  special  effort of such  persons  to  achieve  sound  growth  and
profitability for the Corporation,  and to enhance the Corporation's  efforts to
attract and retain competent Employees, Consultants,  Directors and Advisors (as
defined below).

     2.  Definitions.  The  following  terms  when used  herein  shall  have the
meanings set forth below,  unless a different meaning is plainly required by the
context:

     Advisor.  A person who has been  appointed to and continues to serve on the
Corporation's Scientific Advisory Board.

     Affiliate.  A  corporation  which is a parent  corporation  or a subsidiary
corporation  (within the meaning of Section 424 of the Code) with respect to the
Corporation.

     Board. The Board of Directors of the Corporation.

     Code. The Internal Revenue Code of 1986 , as it has been and may be amended
from time to time.  Reference  to any  section  of the Code  shall  include  any
provision successor thereto.

     Committee.  The Board;  provided,  however,  that if a  committee  has been
delegated  authority pursuant to Section 8.a. to manage and administer the Plan,
then Committee means such committee.

     Common Stock. Shares of the Corporation's  common stock, par value $.01 per
share,  and any  other  shares  of common  stock  from  time to time  authorized
pursuant to the Corporation's Certificate of Incorporation, as amended.

     Consultant.  A person  performing  consulting  or advisory  services to the
Corporation or an Affiliate who is not an Employee.

     Corporation. Immunomedics, Inc., a Delaware corporation.

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     Director. A person who has elected to and continues to serve on the Board.

     Employees.  Officers and other persons  employed by the  Corporation  or an
Affiliate, as determined by the Board or the Committee from time to time.

     Employment Termination Date. The date the Optionee's service as an Employee
terminates,  the date the Optionee's service as a Director terminates,  the date
the  Optionee's  service as an Advisor  terminates,  or the date the  Optionee's
service as a Consultant terminates;  or, if the Optionee serves in more than one
of the foregoing capacities, the last of such dates to occur.

     Exchange  Act.  The  Securities  Exchange Act of 1934,  as amended,  or any
corresponding provisions of any subsequent Federal securities law.

     Incentive  Option.  An option  defined in Section  422A of the Code,  which
meets the requirements of Section 5 and 6.

     Non-Qualified  Option. An option which meets the requirements of Sections 5
and 6.

     Option.  An  Incentive  Option  or a  Non-Qualified  Option  granted  to an
Optionee pursuant to the Plan.

     Option  Agreement.  A written  agreement  between  the  Corporation  and an
Optionee  evidencing the grant of an Option and containing  terms and conditions
concerning the exercise of the Option.

     Option  Price.  The  price to be paid for  shares  of  Common  Stock  being
purchased pursuant to the exercise of an Option.

     Option  Settlement.  The cash,  shares of Common  Stock,  or a  combination
thereof, which may be paid to an Optionee pursuant to Section 7.

     Optionee. An Employee, Director, Consultant or Advisor who has been granted
an Option.  Also  includes  the personal  representative,  heir or legatee of an
Optionee who has the right to exercise an Option upon the death of an Optionee.

     Outside Directors. A Director who is not also an Employee.

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     Plan. The 1992 Stock Option Plan provided for herein,  as it may be amended
from time to time.

     Value.  The closing sale price of the Common  Stock on the Nasdaq  National
Market on the date fair market value is to be determined or, if the Common Stock
is not listed on the  Nasdaq  National  Market,  the  closing  bid price (or the
average of the closing bid price and asked  price) on the  exchange or system on
which the Common Stock is listed or as quoted by the principal  market-maker  of
the Common  Stock;  if the Common Stock cannot be valued by any of the foregoing
methods, fair market value shall be as determined by the Committee.

     3. Eligibility and Participation. Persons eligible to receive Options under
the Plan shall be Employees, Directors,  Consultants or Advisors selected by the
Committee;  provided,  Incentive Options shall only be granted to Employees.  In
determining persons to whom Options, both Incentive and Non-Qualified,  shall be
granted,  the number of shares to be covered by each  Option,  and  whether  the
Option shall be an Incentive  Option or a  Non-Qualified  Option,  or both,  the
Committee  shall take into account the duties of the respective  persons,  their
present and  potential  contribution  to the success of the  Corporation  or any
Affiliate,  their  anticipated  number of years of active service  remaining and
such other factors as it deems  relevant in connection  with  accomplishing  the
purposes of the Plan.  A person who has been granted an Option may be granted an
additional Option or Options as the Committee shall so determine.

     4.  Shares  Subject to the Plan.  The  shares to be offered  under the Plan
shall be the Common Stock, which shares may be authorized but unissued shares or
treasury  shares.  Subject  to the  adjustments  provided  for in Section 9, the
aggregate  number of shares of Common Stock to be delivered upon exercise of all
Options  granted  under the Plan shall not exceed  8,000,000  shares.  Shares of
Common Stock  subject to, but not  delivered  under,  an Option  terminating  or
expiring for any reason prior to the exercise  thereof in full,  shall be deemed
available for Options thereafter granted during the term of the Plan.

     5. Terms and Conditions of All Options. All Options granted hereunder shall
be issued subject to the following terms and conditions:

          a.  Non-Qualified  Options may be granted to any  Optionee.  Incentive
          Options shall be granted only to Employees.  No Incentive Option shall
          be granted to any  Optionee who  immediately  after the granting of an
          Incentive  Option  owns more than 10% of the  issued  and  outstanding
          Common Stock,  unless such Incentive  Option is granted with an Option
          Price of not less than 110% of the  Value of the  Common  Stock at the
          time of the grant of the Option.  For the purpose of this Section 5.a.
          and  Section  6.d.,  an Optionee  is  considered  as owning all of the
          Common Stock owned by his  brothers,  sisters,  spouse,  ancestors and
          lineal descendants and his pro-rata share of all Common Stock owned by
          corporations,  partnerships,  estates  and  trusts  in which he has an
          interest.

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          b. All Options  (other  than those  granted to  Consultants)  shall be
          first  execrable  as to 25% of the  total  number  of shares of Common
          Stock  underlying such Option on the first  anniversary of the date of
          grant,  and to an additional 25% of such shares on each of the second,
          third and fourth anniversaries of such date of grant.

          c.  If  the  Option  is  an  Incentive  Option,  the  aggregate  Value
          (determined at the time the Incentive Option is granted) of the Common
          Stock with respect to which Incentive  Options  granted  hereunder and
          incentive   stock  options   granted  under  any  other  plan  of  the
          Corporation  (or any parent or subsidiary  thereof) are exercisable by
          the Optionee for the first time in any calendar  year shall not exceed
          $100,000.

          d. Options shall not be transferable by the Optionee otherwise than by
          will or the laws of descent and distribution, and shall be exercisable
          during his lifetime only by him; except that the Committee,  either at
          or after the grant of an Option, may permit a Non-Qualified  Option to
          be transferable to any or all of the spouse, child or grandchild of an
          Optionee or to a trustee of a trust for the sole benefit of any or all
          of the foregoing persons.

          e. Upon an Employment  Termination Date (other than as a result of the
          death of the Optionee), the Options held by such Optionee at such date
          shall terminate;  provided,  however, that the Committee,  in its sole
          and  uncontrolled  discretion,  may  extend  such  termination  of the
          Options until a date not more than three months after such  Employment
          Termination  Date,  or if  such  termination  is as a  result  of  the
          Optionee's  permanent and total disability (as that term is defined in
          Section  105(d)(4) of the Code and referred to herein as "Disability")
          until a date not more than one year after such Employment  Termination
          Date.  The  Committee  may,  in  specific  cases  and in its  sole and
          uncontrolled  discretion,  permit the exercise by an Optionee,  within
          such three and 12 month  periods of all or part of the  Options  which
          was not exercisable on the Employment Termination Date.

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          f. In the  event  of the  Optionee's  death  prior  to his  Employment
          Termination  Date or, if the termination  date of such Option has been
          extended for three months or more in accordance  with  subsection 5.e.
          hereof,  his death  during  such  extended  period,  the Option  shall
          terminate upon the earlier to occur of (i) 12 months after the date of
          the Optionee's death, (ii) the Option's expiration date, or (iii) such
          other date as shall be specified in the Option  Agreement.  The Option
          shall be  exercisable  during such period after the  Optionee's  death
          with respect to the number of shares as to which the Option shall have
          been  exercisable  on the date  immediately  preceding the  Optionee's
          death.

          g. Any exercise or attempt to exercise any Option by an Optionee,  and
          any request for any Option  Settlement  in  accordance  with Section 7
          hereof,  during a period  commencing 180 days prior to the termination
          of  such  Optionee's   employment  or  other   relationship  with  the
          Corporation for any reason and ending 90 days after such  termination,
          shall be subject to the  Corporation's  right to (i) deny the exercise
          of such Option or such  request,  (ii)  rescind  the  exercise of such
          Option (if the Option has been exercised but the underlying  shares of
          Common  Stock have not been sold),  or (iii) be paid by the  Optionee,
          upon  the  demand  of  the  Corporation,  the  amount  of  any  Option
          Settlement  paid and the  amount  of  profits  (i.e.,  the  difference
          between  the  exercise  price of the  Option and the sale price of the
          Common Stock acquired upon such exercise)  received by the Optionee as
          a result  of the  exercise  of such  Option  if such  Option  has been
          exercised  and the  underlying  shares of Common Stock have been sold.
          The right of the Corporation provided in the foregoing sentence may be
          exercised only (i) on or prior to the ninetieth day after  termination
          of the  employment  or other  relationship  of the  Optionee  with the
          Corporation  and (ii) if the Board of  Directors  determines,  in good
          faith, that the Optionee has breached a material duty or obligation to
          the Corporation.

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     6. Terms and Conditions of Option  Agreement.  The Committee shall have the
power,  subject  to  the  limitations  contained  in  this  Plan,  to  prescribe
additional  terms and  conditions  in respect of the granting or exercise of any
Option under the Plan and in particular  shall prescribe the following terms and
conditions, which shall be contained in the Option Agreement for such Option:

          a.  Whether  the  Option is an  Incentive  Option  or a  Non-Qualified
          Option.

          b. The number of shares of Common Stock to which the Option pertains.

          c. The exercise price of the Option, which shall not be less than 100%
          of the  Value of the  Common  Stock  at the  time of the  grant of the
          Option, except as provided in Section 5.a.

          d. The term of the  Option,  which  shall not exceed 10 years from the
          date on which the Option is granted;  provided,  if the Optionee  owns
          more than 10% of the  issued and  outstanding  Common  Stock,  and the
          Option is an Incentive Option, the term shall not exceed five years.

          e. The method or time when the Option may be  exercised in whole or in
          part, for Options granted to Consultants.

          f.  Whether the Option Price may be paid in whole or in part in shares
          of Common Stock then owned by the Optionee.

          g. For a Non-Qualified  Option,  the provisions for the withholding of
          Federal,  state and local  income or other taxes which shall be due in
          connection with the exercise of the Non-Qualified Option.

          h. For a Non-Qualified Option,  whether such Option is transferable by
          the Optionee, as permitted by Section 5.d.

          i. Each Option  Agreement  shall  provide  that,  upon  request by the
          Committee for such a representation, the Optionee shall deliver to the
          Committee at the time of any exercise of an Option or portion thereof,
          a  written  representation  that  the  shares  of  Common  Stock to be
          acquired upon such exercise are to be acquired for  investment and not
          for  resale  or with a view to the  distribution  thereof.  Upon  such
          request,  delivery of such representation prior to the delivery of any
          shares of Common Stock issued upon  exercise of an Option and prior to
          the expiration of the Option period shall be a condition  precedent to
          the right of the Optionee or such other person to purchase any shares.

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     7. Option Settlement Provisions. Each Optionee may request that, in lieu of
exercising an Option, he receive shares of Common Stock,  cash, or a combination
of Common  Stock and cash,  having a fair  market  value  equal to the amount by
which the Value of the shares of Common Stock  subject to the Option at the time
of such request exceeds the Option Price (the "Option Settlement"), as follows:

          a. The request of the Optionee shall be in a writing  delivered to the
          Committee  during the period  commencing with the third day after, and
          ending  with the  twelfth  day after the  release  by the  Corporation
          quarterly or annual summary statements of earnings of the Corporation.

          b. The Committee shall, in its sole discretion,  determine  whether to
          permit  an  Optionee  to  receive  an  Option  Settlement  in  lieu of
          exercising  the Option and, if the Committee  determines to permit the
          Optionee to receive an Option Settlement,  the Committee,  in its sole
          discretion,  shall  determine  what  portion of the Option  Settlement
          shall be in cash and what portion shall be in shares of Common Stock.

          c.  For  the  purposes  of  determining   the  amount  of  the  Option
          Settlement,  the Value of a share of Common Stock shall be  determined
          on the date  the  written  request  referred  to in  Section  7.a.  is
          received  by the  Committee;  provided,  that the amount of the Option
          Settlement  shall not exceed  twice the Option  Price of the shares of
          Common Stock under the Option  being  canceled.  For  example,  if the
          Option Price per share is $7, the Option  Settlement cannot exceed $14
          per share.

          d. Upon the payment of an Option  Settlement,  the Option with respect
          to which the Option  Settlement was paid shall be canceled the same as
          if the Option had been exercised in full.

     8. Administration of Plan.

          a. The Plan shall be  administered  by a committee  (the  "Committee")
          comprised of at least two Outside Directors, each of whom comes within
          the  definition  of  "non-employee  director"  under Rule  16b-3(b)(3)
          promulgated under the Exchange Act.

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          b. Subject to such orders or  resolutions  not  inconsistent  with the
          provisions  of the Plan, as may from time to time be issued or adopted
          by the Board,  the  Committee  shall have full power and  authority to
          interpret the provisions and supervise the administration of the Plan;
          provided,  however,  that the grants of  options to Outside  Directors
          other than  pursuant to Section  8.c.  shall be ratified by the Board.
          All decisions,  determinations  and  selections  made by the Committee
          pursuant to the provisions of the Plan and applicable  existing orders
          or resolutions of the Board shall be final.  Each Option granted shall
          be  evidenced  by  an  Option  Agreement  containing  such  terms  and
          conditions  that may be approved by the  Committee and which shall not
          be  inconsistent  with the Plan and the orders and  resolutions of the
          Board with respect thereto.

          c. In  addition  to any other  Options  granted  to  Directors  by the
          Committee,  each Outside  Director shall be granted  Options under the
          Plan in accordance with the formula set fourth below:

               (i)  Outside  Directors  shall be granted  an Option to  purchase
               10,000  shares of Common  Stock upon the date of his  election or
               appointment to the Board for the first time.

               (ii) On each  July 1 during  the term of the Plan,  each  Outside
               Director who has been a Director for not less than twelve  months
               prior to such date shall be granted an Option to purchase  10,000
               shares of Common Stock,  and each Outside Director who has been a
               Director  for at least three  months but less than twelve  months
               prior to the date of grant,  shall  receive an Option to purchase
               such number of shares of Common Stock  determined by  multiplying
               10,000 times a fraction,  the  denominator of which is twelve and
               the  numerator  of which is the number of complete  months  which
               such person has served as an Outside Director.

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               (iii) All  Options  granted  to  Outside  Directors  shall (1) be
               Non-Qualified Options, (2) be exercisable at a price equal to the
               Value at the date of grant and (3) be  exercisable  for a term of
               10 years.

     9.  Adjustments  Upon  Changes  in  Capitalization.  Not  withstanding  the
limitation  set forth in  Section  4, in the  event of a merger,  consolidation,
reorganization,  stock  dividend,  stock  split or  other  change  in  corporate
structure or capitalization affecting the Common Stock, the Committee shall make
an appropriate  adjustment in the maximum number of shares  available  under the
Plan or to any one individual and in the number,  kind,  Option Price, and other
terms  relating to shares of Common Stock  subject to Options  granted under the
Plan. Any such adjustment  shall be made so as not to constitute a modification,
extension or renewal of the Option  within the meaning of Section  425(h) of the
Code.

     10.  Time of  Granting  Options.  Except for  Options  granted  pursuant to
Section 8 hereof,  nothing contained in the Plan or in any resolution adopted or
to be adopted by the Board or by the  stockholders  of the  Corporation,  and no
action taken by the  Committee  (other than the granting of a specific  Option),
shall constitute the granting of an Option hereunder.  The granting of an Option
pursuant to the Plan shall take place on the date such Option is approved by the
Committee.

     11. Amendment and Discontinuance.  The Board may discontinue,  amend, alter
or suspend the Plan at any time or from time to time,  subject to such approvals
as may be required  pursuant to (i) the Code, (ii) the laws of the Corporation's
jurisdiction  of  incorporation,  and  (iii)  the  Exchange  Act  or  the  rules
promulgated  thereunder.  Any Option which is outstanding  under the Plan at the
time of its amendment or termination  shall remain in effect in accordance  with
its terms and  conditions and those of the Plan as in effect when the Option was
granted.

     12. Merger, Consolidation or Sale of Assets or Stock. In the event that (i)
the Corporation merges or consolidates with another  corporation or entity which
results in the Corporation not being the surviving  corporation or entity,  (ii)
all or  substantially  all of the  Corporation's  assets are acquired by another
corporation or entity, (iii) the Corporation is liquidated or dissolved, or (iv)
there is a sale of shares of Common Stock as a result of which any one person or
entity,  or any group of persons or entities  which are  affiliated or which are
acting in concert, becomes the beneficial owner of in excess of fifty percent of
the then outstanding  shares of Common Stock,  then each Optionee shall have the
right,  immediately  prior to any such  event,  to exercise  any Option  granted
hereunder,  in whole or in part,  as to the full  number  of shares  which  such

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Optionee would otherwise have been able to purchase during the remaining term of
the Option,  whether or not otherwise  exercisable at such time according to its
terms.  In addition,  any Optionee may request to receive at such time an Option
Settlement,  as provided in Section 7, notwithstanding that such election is not
made during the period set forth in Section 7.a. Upon the occurrence of any such
merger,  consolidation or sale of assets, the surviving or acquiring corporation
or entity shall,  subject to the provision of the following sentence,  adopt the
Plan and upon the exercise of an Option  after the closing of such  transaction,
the Optionee  shall,  at no additional  costs (other than the Option Price),  be
entitled to receive,  in lieu of shares of Common Stock, the number and class of
shares of capital  stock or other  securities  to which the Optionee  would have
been  entitled  pursuant  to  the  terms  of  the  merger  or  consolidation  if
immediately  prior  thereto the  Optionee  had been the holder of record of such
number of shares of Common Stock as such Optionee would otherwise have been able
to purchase  during the remaining  term of the Option,  whether or not otherwise
exercisable at such time according to its terms.  If such surviving or acquiring
corporation or entity does not adopt the Plan, such  corporation or entity shall
terminate all outstanding  Options under the Plan by paying the holders thereof,
in cash,  the difference  between the aggregate  Option Price of the Options and
the price per share paid for or  allocated to the shares of Common Stock in such
transaction.

     13. Effectiveness and Termination of the Plan.

          a. The Plan shall become  effective  upon  adoption by the Board.  The
          Plan shall be rescinded  and all Options  granted  hereunder  shall be
          null and void  unless  within 12 months  from  adoption of the Plan it
          shall have been approved by a vote of the holders of a majority of all
          the issued and  outstanding  shares of Common Stock present  either in
          person or by proxy at a meeting duly held for such purpose.

          b. The Plan shall terminate on the earliest to occur of:

               (i) the date when all shares of Common Stock  available under the
               Plan shall have been  acquired  through  the  exercise of Options
               granted under the Plan,  or the payment of Settlement  Options in
               lieu of such exercise;

               (ii) 10  years  after  the  date of  adoption  of the Plan by the
               Board; or

               (iii) such other date as the Board shall determine.

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     14. Governing  Law.  The  provisions  of  the  Plan  shall  be  construed,
administered and enforced according to the laws of the State of Delaware.

     15. Miscellaneous.

          a. The captions and section  headings used herein are for  convenience
          only,  shall not be  deemed  part of the Plan and shall not in any way
          restrict  or modify  the  context  and  substance  of any  section  or
          paragraph hereof.

          b. The Plan shall be construed  in such a fashion  that all  Incentive
          Options shall qualify as "incentive  stock options" under Section 422A
          of the Code.

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