EXHIBIT 10.1





                               CYTOGEN CORPORATION

                              AMENDED AND RESTATED
                             1995 STOCK OPTION PLAN

                       (last amended as of June 19, 2001)


1.   Purpose; Effective Date.

     (a) The  purposes  of this Plan are to  further  the  interests  of Cytogen
Corporation  (the  "Company") and its  Subsidiaries by retaining the services of
persons now serving as  officers  and other  employees  and  consultants  of the
Company and its  Subsidiaries,  attracting and retaining the services of persons
capable of serving as officers, employees and consultants of the Company and its
Subsidiaries  and providing  incentives  for such  employees and  consultants to
exert   maximum   efforts  to  promote  the  success  of  the  Company  and  its
Subsidiaries.

     (b) The  effective  date of this  Plan is March  28,  1995.  This Plan will
become  effective  on that date,  subject to approval of the Plan not later than
September  30, 1995 by a majority of the votes cast at a duly held  stockholders
meeting at which a quorum  representing  a majority  of all  outstanding  voting
stock is, either in person or by proxy,  present and voting on the Plan. Nothing
in this Plan  shall  affect  the  rights or  obligations  of  holders of options
granted under any other Company stock option plan.

2.   Definitions.

     Whenever used in this Plan, the following  terms will have the meanings set
forth in this paragraph:

     "Board of Directors" means the Board of Directors of the Company.

     "Code" means the U.S. Internal Revenue Code of 1986, as amended.

     "Committee" means the committee described in paragraph 3.

     "Common  Stock" means the common stock,  par value $. 01 per share,  of the
Company.

     "Date of Grant"  means with  respect  to any Option the date the  Committee
approves  the grant of the Option or such later date as may be  specified by the
Committee as the date the option will become effective.

     "Disinterested   Director"   means  a  member   of  the   Board  who  is  a
"disinterested  person"  within  the  meaning  of  Rule  16b-3(d)(3)  under  the
Securities Exchange Act of 1934, or any successor provision.



     "Eligible  Consultant" means a consultant providing services to, and who is
not an employee of, the Company or any of its Subsidiaries.

     "Employee"  means  any  person  employed  by  the  Company  or  any  of its
Subsidiaries (including, without limitation, a person employed by the Company or
any of its Subsidiaries who is also an officer or director of the Company or any
of its Subsidiaries).

     "Exercise Price" means with respect to any Option the price per share which
must be paid upon exercise of the Option.

     "Fair Market  Value" means (i) if the Common Stock is traded in a market in
which actual  transactions are reported,  the mean of the high and low prices at
which the Common  Stock is reported to have traded on the  relevant  date in all
markets  on which  trading in the Common  Stock is  reported,  or if there is no
reported sale of the Common Stock on the relevant  date, the mean of the highest
reported bid price and lowest  reported  asked price for the Common Stock on the
relevant date,  (ii) if the Common Stock is Publicly  Traded but only in markets
in which there is no reporting of actual  transactions,  the mean of the highest
reported bid price and the lowest  reported  asked price for the Common Stock on
the relevant  date,  or (iii) if the Common Stock is not  Publicly  Traded,  the
value of a share of Common  Stock as  determined  by the most  recent  valuation
prepared by an independent expert at the request of the Committee.

     "Incentive  Stock  Option"  means any Option  that at the time of the grant
qualifies and is  designated as an incentive  stock option within the meaning of
Section 422 of the Code.

     "Non-Qualified  Option"  means any Option  that is not an  Incentive  Stock
Option.

     "Option" means any Incentive Stock Option or  Non-Qualified  Option granted
under this Plan.

     "Option  Agreement" means an agreement in such form as may be determined by
he Committee,  executed and delivered by the Company to the holder of any Option
with respect to that Option.

     "Outside  Director"  means  a  member  of the  Board  who is not a  current
employee of the Company (or a related  entity),  is not a former employee who is
receiving   compensation  for  prior  services  (other  than  benefits  under  a
tax-qualified  retirement  plan), was not an officer of the Company at any time,
and is not currently receiving remuneration,  either directly or indirectly,  in
any capacity other than as a director.

     "Plan" means the Cytogen Corporation 1995 Stock Option Plan, as amended.

     "Publicly Traded" means, with respect to any class of stock, that the class
of stock  is  required  to be  registered  under  Section  12 of the  Securities
Exchange  Act of 1934,  as  amended,  or that  stock of that class has been sold
within the preceding 12 months in an underwritten public offering.


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     "Subsidiary"  means any  corporation  that,  at the time in  question  is a
subsidiary  corporation  of the Company  within the meaning of section 424(f) of
the Code.

     "Ten Percent Shareholder" means, with respect to the grant of any Option, a
person who at the Date of Grant is the beneficial owner of stock possessing more
than 10% of the  total  combined  voting  power of all  classes  of stock of the
Company.

     "Termination  of  Service"  means (a) the time  when the  employee-employer
relationship between an Employee and the Company ceases to exist for any reason,
or (b) the time  when an  officer  who is not also an  Employee  ceases to be an
officer  of the  Company  for any  reason  or (c)  the  time  when  an  Eligible
Consultant  ceases to be such a consultant  for any reason,  including,  but not
limited to, a termination by resignation,  discharge, death, Total Disability or
retirement.  Any leave of absence  taken with the  consent of the  Company for a
period of not more than 90 days shall not be a  Termination  of  Service,  or if
longer,  so long as the  optionee's  right to  reemployment  with the Company is
guaranteed by contract.  If the period of leave exceeds 90 days and if the right
to reemployment  is not guaranteed by contract,  the Termination of Service will
be deemed to occur on the 91st day of the leave.

     "Total Disability" means inability of an Employee or Eligible Consultant to
engage in any substantial gainful activity by reason of a medically determinable
physical or mental  impairment which can be expected to result in death or which
has lasted or can be expected to last for a  continuous  period of not less than
12 months.  All  determinations  as to the date and extent of  disability  of an
Employee or Eligible Consultant will be made by the Committee.

3.   Administration.

     (a) This Plan shall be administered by a Committee, which shall be composed
of not less than two Outside Directors who are also Disinterested Directors. The
Committee  may, from time to time,  adopt or rescind rules and  regulations  for
carrying out the  provisions  and purposes of this Plan.  Subject to the express
provisions  of this  Plan,  the  Committee  shall  have sole  authority,  in its
absolute  discretion,  to  determine  which  officers,  Employees  and  Eligible
Consultants shall receive Options,  the time when Options shall be granted,  the
terms and  provisions of the Options  (which may differ from one another) and to
do  everything  necessary or  appropriate  to administer  this Plan,  including,
without  limitation,  interpreting  the provisions of this Plan and the Options.
All  determinations  made by the  Committee  with  respect  to this Plan and the
Options shall be final, binding and conclusive.


     (b) No member of the  Committee  shall be liable for any act or omission of
the Committee or any other member of the  Committee,  or for any act or omission
on his own part, in connection with the  administration  of this Plan, unless it
resulted from the member's own willful misconduct.


4.   Persons Eligible to Receive Options.

     (a) Options may be granted  under this Plan only to persons who at the Date
of Grant  either (i) are  officers,  Employees  or Eligible  Consultants  of the

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Company  or any of its  Subsidiaries  or (ii) have  agreed  to become  officers,
Employees  or Eligible  Consultants  of the Company or any of its  Subsidiaries,
and, in either  case,  are  determined  by the  Committee  to be of  substantial
importance to the Company or any of its Subsidiaries.

     (b)  Options  granted to persons  who are not yet  officers,  Employees  or
Eligible  Consultants  at the  Date of  Grant  may not be  exercised  until  the
optionee  has become an  officer,  Employee or  Eligible  Consultant,  and shall
expire if the  optionee  fails to commence  service as an  officer,  Employee or
Eligible Consultant within six months (or such other period as the Committee may
determine) after the Date of Grant.

     (c)  Incentive  Stock  Options  may be  granted  only  to  persons  who are
Employees  at the Date of  Grant,  and only on such  terms  as are  provided  in
paragraphs 6, 7 and 8 hereof.

     (d) No Employee or Eligible Consultant to whom Options may be granted under
this Plan may be granted Options to purchase more than 200,000 shares in any one
calendar year.

5.   Stock Subject to the Plan.

     (a)  Subject to any  adjustment  as provided  in  paragraph  9, the maximum
number of shares of Common Stock as to which  Options may be granted  under this
Plan is 4,502,635  shares reduced by the number of outstanding  options  granted
under the Cytogen  Corporation 1989 Employee Stock Option Plan (the "1989 Plan")
that are exercised  after the effective date of this Plan. If any Option expires
or is cancelled or  surrendered  without being  exercised in full, the number of
shares as to which the Option is not exercised  will once again become shares as
to which  new  Options  may be  granted.  The  Common  Stock  which is issued on
exercise of Options may be authorized  but unissued  shares or shares which have
been issued and reacquired by the Company.

     (b) For  administrative  purposes  only, the Committee  shall  establish an
account  indicating the number of shares of Common Stock as to which Options may
then be granted under this Plan (the "Current  Account"),  and the Committee may
issue  Options  only with respect to the shares of Common  Stock  available  for
grant as set forth in the Current Account. The Current Account shall contain the
number of shares available for grant calculated as follows: (a) 4,502,635, minus
(b) the number of shares of Common Stock  subject to options  granted  under the
1989 Plan that are exercised  after the effective  date of this Plan,  minus (c)
the number of shares of Common  Stock  subject to  outstanding  options  granted
under the 1989 Plan and this Plan, plus (d) the number of shares of Common Stock
subject to outstanding options granted under the 1989 Plan and/or this Plan that
expire, are cancelled or surrendered without being exercised in full.

6.   Grants of Options.

     (a) Subject to paragraph 4(d), the Committee will have complete  discretion
to  determine  when,  and to which  officers  or  other  Employees  or  Eligible
Consultants,  Options are to be granted, the number of shares of Common Stock to
which Options granted to each officer or other Employee or Eligible  Consultant,
will relate,  whether and to what extent Options  granted to an officer or other

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Employee  or  Eligible   Consultant,   will  be  Incentive   Stock   Options  or
Non-Qualified  Options and, subject to the provisions of paragraphs 7 and 8, the
Exercise Price and the term of each Option. The Committee may, in its discretion
at the time of granting the Option,  provide that the Exercise Price may be paid
in cash,  by the surrender of Common Stock,  by an  interest-bearing  promissory
note, or by other means; subject, however, to any requirements of applicable law
which may limit the type or amount of such non-cash consideration. If payment by
promissory note is permitted:  (i) the optionee shall be required to make a cash
payment upon exercise of the Option of not less than 20% of the Exercise  Price;
(ii) the note shall provide for full recourse  against the maker;  and (iii) the
note shall be payable in full prior to its stated  maturity upon the  optionee's
Termination of Service for any reason other than death or Total Disability.

     (b) Any Options which are not  designated  as Incentive  Stock Options when
they are granted will be Non-Qualified Options.

     (c)  Promptly  after the Date of Grant of each  Option,  the Company  shall
cause an Option  Agreement  to be executed  and  delivered  to the holder of the
Option.  The Option  Agreement shall clearly state whether the Option granted is
or is not an Incentive Stock Option.  Separate Option  Agreements  shall be used
for Incentive Stock Options and Non-Qualified Stock Options.

     (d) Except as otherwise  determined  by the  Committee,  and subject to the
requirements  of  applicable  law,  the entire  Exercise  Price  received by the
Company upon the exercise of an option shall  constitute  stated  capital to the
extent of the  aggregate  par value of the Common Stock issued upon  exercise of
the Option.

     (e) Any  Option  granted  under  this  Plan  prior  to the date the Plan is
approved by the Company's stockholders shall not be exercisable unless and until
the Plan is so approved.

7.   Option Provisions.

     (a) Exercise Price. No  consideration  shall be payable by any optionee for
the grant of an Option.  Subject to the  provisions  of  paragraph  7(a)(i)  and
paragraph  8, the  Exercise  Price of each Option will be as  determined  by the
Committee.

          (i) The  Committee  shall not grant any Option with an exercise  price
     that is less than 100% of the Fair Market Value of the underlying  stock on
     the date of grant or reduce the exercise  price of any Option granted under
     the Plan.


     (b) Term.  The term of each Option will be as determined by the  Committee,
but in no event  will the term of an Option be  longer  than ten years  from the
Date of Grant, or five years in the case of an Incentive Stock Option granted to
a Ten Percent Shareholder.  Options may not be exercised before six months after
the Date of Grant.  Options will cease to be exercisable prior to the expiration
of their term under certain  circumstances  as provided in paragraphs 7(f), (g),
and (h).  Subject  to the  foregoing,  and to any  vesting  or other  conditions
imposed at the time it is  granted,  an Option may be  exercised  in whole or in
part at any time, or from time to time, during its term.

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     (c) Manner of Exercise.  To exercise an Option,  the person  exercising the
Option must deliver to the Company, at its principal office:

          (i) a notice of exercise,  which states the extent to which the Option
     is being exercised;

          (ii) a certified or bank cashier's check in an amount, or Common Stock
     with a Fair Market Value,  equal to the Exercise  Price of the Option times
     the number of shares as to which it is being exercised, or consideration in
     such other form as may be permitted  under the terms on which the Option is
     granted; and

          (iii) a certified  or bank  cashier's  check equal to any  withholding
     taxes the Company is required to pay because of the exercise of the Option.

     The  Committee  may permit an  Employee,  as an  alternative  to making the
     payment  described in clause (iii),  to authorize the Company to withhold a
     sum equal to the withholding  taxes the Company is required to pay from the
     Employee's  salary  and bonus  payments  over a period of not more than six
     months (or such  longer  period as the Company  may  approve).  The date on
     which the Company  receives all the items specified in this subsection will
     be the date on which the Option is exercised to the extent described in the
     notice of election.

     (d) Delivery of Stock  Certificates.  As promptly as  practicable  after an
Option is  exercised,  the Company will deliver to the person who  exercises the
Option certificates,  registered in that person's name,  representing the number
of shares of Common  Stock which were  purchased  by the exercise of the Option.
Each  certificate  may bear a legend to indicate,  if  applicable,  that (i) the
Common Stock  represented by the certificate  was issued in a transaction  which
was not registered under the Securities Act of 1933, as amended, and may only be
sold or  transferred in a transaction  which is registered  under that Act or is
exempt from the registration requirements of that Act, and (ii) the Common Stock
represented by the certificate is subject to the obligation of the holder to pay
any unpaid balance of the Exercise Price (whether  pursuant to a promissory note
or  otherwise),  and/or  that the  Common  Stock is  pledged  to secure  such an
obligation.

     (e)  Nontransferability  of Options.  During the  lifetime of the person to
whom an Option is issued, the Option may be exercised only by that person or his
or her guardian or legal representative.  An Option may not be assigned, pledged
or  hypothecated  in any way, will not be subject to execution,  and will not be
transferable otherwise than by will or the laws of descent and distribution. The
Company will not recognize any attempt to assign, transfer,  pledge, hypothecate
or otherwise  dispose of an Option  contrary to the  provisions of this Plan, or
any levy of any attachment or similar  process upon any Option,  and,  except as
expressly  stated in this Plan,  the Company  will not be required  to, and will
not,  issue  Common  Stock on exercise of an Option to anyone who claims to have
acquired that Option from the person to whom it was granted.


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     (f)  Termination of Service of Holder of Option Other Than Because of Total
Disability or Death. If there is a Termination of Service of a person to whom an
Option has been  granted,  other than by reason of the  person's  death or Total
Disability,  each  Option  held by the person  may be  exercised  (if  otherwise
exercisable)  until  the  earlier  of (i)  the  end of  the  three-month  period
immediately  following  the  date  of  the  Termination  of  Service,  (ii)  the
expiration  of the term  specified in the Option,  or (iii) such earlier time as
may be determined by the Committee at the time of granting the Option.

     (g) Total  Disability  of Holder of Option.  If there is a  Termination  of
Service of a person to whom an Option  has been  granted by reason of his or her
Total Disability,  each Option held by the person may be exercised (if otherwise
exercisable) until the earlier of (i) the end of the one-year period immediately
following the date of the  Termination  of Service,  (ii) the  expiration of the
term specified in the Option, or (iii) such earlier time as may be determined by
the Committee at the time of granting the Option.

     (h) Death of Holder of Option.  If there is a  Termination  of Service of a
person to whom an Option has been  granted  by reason of his or her death,  or a
former officer or Employee or Eligible Consultant dies following the date of his
or her  Termination  of  Service  but at a time  when an Option  still  would be
exercisable by that person but for the death of the person,  each Option held by
the  person at the time of his or her death may be  exercised  by the  person or
persons  to  whom  the  Option  passed  by will or by the  laws of  descent  and
distribution  (but by no other  persons) until the earlier of (i) the end of the
one-year period immediately following the date of death (or such other period as
may be determined by the Committee at the time of granting the Option), (ii) the
expiration  of the term  specified  in the Option,  or (iii) if the death occurs
after the  Termination  of  Service,  the end of the  period in which the Option
could be exercised under paragraph 7(f) or (g).

     8. Special  Provisions  Relating to Incentive  Stock Options.  No Incentive
Stock  Option may be granted  after March 27,  2005.  The  Exercise  Price of an
Incentive  Stock  Option will be not less than 100% of the Fair Market  Value of
the Common Stock on the Date of Grant of the Option.  An Incentive  Stock Option
may not be granted to a person who, at the time the Option is granted,  is a Ten
Percent  Shareholder,  unless (i) the  Exercise  Price of the Option is at least
110% of the Fair Market  Value of the Common Stock on the Date of Grant and (ii)
the Option by its terms is not  exercisable  after the  expiration of five years
from the Date of Grant.  To the extent  that the  aggregate  Fair  Market  Value
(determined  at the time an  Incentive  Stock  Option is  granted) of the Common
Stock with respect to which Incentive Stock Options are first  exercisable by an
Employee during any calendar year (under this Plan and any other incentive stock
option plans of the Company) exceeds $100,000,  such Options shall be treated as
Non-Qualified  Options.


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9.   Recapitalization.

     (a) The  existence of  outstanding  Options shall not affect in any way the
right or power of the Company or its  stockholders  to make or authorize  any or
all  adjustments,  recapitalizations,  reorganizations  or other  changes in the
Company's capital  structure or its business,  or any merger or consolidation of
the Company,  or any issue of bonds,  debentures,  preferred or prior preference
stock  ahead of or  affecting  the Common  Stock or the rights  thereof,  or the
dissolution or liquidation of the Company, or any sale or transfer of all or any
part of its assets or business or any other corporate act or proceeding, whether
of a similar character or otherwise.  Unless otherwise  determined by the Board,
the  issue  by the  Company  of  shares  of stock of any  class,  or  securities
convertible  into  shares of stock of any class,  for cash or  property,  or for
labor or services  either  upon  direct  sale or upon the  exercise of rights or
warrants to subscribe therefor, or on conversion of shares or obligations of the
Company convertible into such shares or other securities,  shall not affect, and
no adjustment by reason thereof shall be made with respect to, the number, class
or price of shares of Common Stock then subject to outstanding Options.

     (b) If as a result of any (i)  reorganization or liquidation of the Company
or (ii)  reclassification of the Company's capital stock, or (iii) consolidation
or merger of the Company  with or into  another  corporation,  or sale of all or
substantially  all the assets of the Company (a reorganization or liquidation of
the Company or  reclassification  of the Company's  capital stock,  or a merger,
consolidation  or  sale  of the  type  described  in  this  subsection  being  a
"Corporate  Transaction")  while an Option is  outstanding,  the  holders of the
Common  Stock become  entitled to receive  with  respect to their Common  Stock,
securities  or assets other than,  or in addition to, their Common  Stock,  upon
exercise of that Option the holder will receive what the holder would have owned
if the  holder  had  exercised  the  Option  immediately  before  the  Corporate
Transaction which occurred while the Option was outstanding and had not disposed
of  anything  the  holder  would  have  received  as a  result  of that  and all
subsequent Corporate Transactions.

10. Rights of Option Holder.

     (a) The holder of an Option  will not have any rights as a  stockholder  by
reason of holding that Option.  Upon  exercise of an Option,  the holder will be
deemed to acquire the rights of a stockholder when, but not before, the issuance
of Common Stock as a result of the exercise is recorded in the stock  records of
the Company.

     (b)  Nothing in this Plan or in the grant of an Option will confer upon any
Employee  the  right  to  continue  in the  employment  of the  Company  or will
interfere with or restrict in any way the rights of the Company to discharge any
Employee at any time for any reason whatsoever,  with or without cause, nor will
it impose any obligation on the Employee to remain in the employ of the Company.


     11. Laws and Regulations. The obligation of the Company to sell and deliver
shares of Common Stock on exercise of Options  will be subject to the  condition
that legal counsel for the Company be satisfied  that the sale and delivery will
not violate the  Securities  Act of 1933,  as amended,  or any other  applicable
laws,  rules or regulations.

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12.  Withholding of Taxes.

     (a) In  addition  to the  requirement  in  paragraph  7(c) that in order to
exercise  an Option a person  must make a payment to the  Company  or  authorize
withholding in order to enable the Company to pay any withholding taxes due as a
result of the  exercise,  if a person who  exercised an  Incentive  Stock Option
disposes of shares of Common Stock acquired  through  exercise of that Incentive
Stock  Option  either  (i)  within  two  years  after  the  Date of Grant of the
Incentive  Stock Option or (ii) within one year after the issuance of the shares
on exercise of the Incentive  Stock  Option,  the person will notify the Company
promptly of the  occurrence of the event and, if the event was a disposition  of
Common  Stock  acquired on exercise of an  Incentive  Stock  Option,  the amount
realized upon the disposition.

     (b) If,  whether  because of a  disposition  of Common  Stock  acquired  on
exercise of an Incentive Stock Option, or otherwise,  the Company is required to
pay withholding  taxes to any Federal,  state or other taxing  authority and the
Employee  fails to  provide  the  Company  with the funds with which to pay that
withholding tax, the Company may withhold up to 50% of each payment of salary or
bonus to the  Employee  (which  will be in  addition  to any other  required  or
permitted  withholding),  until the Company has been  reimbursed  for the entire
withholding tax it was required to pay.

     (c) The  obligations  contained  in  this  paragraph  12  shall  bind  each
optionee,  and each optionee, by accepting and/or exercising an Option, shall be
deemed to agree to observe and comply with them.

     13.  Reservation of Shares. The Company will at all times keep reserved for
issuance  on  exercise  of  Options  a number  of  authorized  but  unissued  or
reacquired  shares of Common  Stock  equal to the  maximum  number of shares the
Company may be required to issue on exercise of outstanding Options (assuming no
subsequent adjustments under paragraph 9).

     14.  Amendment of the Plan. The Board of Directors may at any time and from
time to time modify or amend this Plan in any respect  effective at any date the
Board of  Directors  determines;  provided,  that  without  the  approval of the
stockholders  of the  Company  the Board of  Directors  may not,  (i)  except as
provided in paragraph 9,  increase the maximum  number of shares of Common Stock
which may be issued on exercise of Options  granted under this Plan; (ii) change
the  categories  of persons  eligible to receive  Options;  (iii)  increase  the
per-optionee  limit  specified  in  paragraph  4(d),  (iv) take any other action
requiring the approval of the  stockholders  of the Company in order to maintain
the exemption available under Rule 16b-3 (or any similar rule) of the Securities
and Exchange  Commission,  or (v) modify the provisions of paragraph 7(a)(i). No
modification  or amendment of this Plan will,  without the consent of the holder
of an  outstanding  Option,  adversely  affect the  holder's  rights  under that
Option.

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     15. Interpretation The Committee shall have the power to interpret the Plan
and to make and amend rules for putting it into effect and  administering it. It
is  intended  that the  Incentive  Stock  Options  granted  under the Plan shall
constitute  incentive  stock  options  within the  meaning of section 422 of the
Code,  that the  Non-Qualified  Options  shall  constitute  property  subject to
federal income tax pursuant to the provisions of section 83 of the Code and that
the Plan shall  qualify  for the  exemption  available  under Rule 16b-3 (or any
similar rule) of the  Securities  and Exchange  Commission.  It is also intended
that all  compensation  income  recognized  by  optionees  as the  result of the
exercise of Options or the  disposition  of Common Stock acquired on exercise of
Options shall be considered performance-based  compensation excludable from such
optionee's  "applicable employee  remuneration" pursuant to section 162(m)(4)(C)
of the Code. The provisions of the Plan shall be interpreted and applied insofar
as possible to carry out such intent.

     16.  Termination of the Plan.  This Plan shall  terminate on March 27, 2005
unless sooner  terminated.  The Board of Directors may suspend or terminate this
Plan at any time or from time to time,  but no such action may adversely  affect
the rights of a person holding an outstanding Option.


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