Exhibit 10.1


                          SECURITIES PURCHASE AGREEMENT

     This Securities  Purchase  Agreement (this "Agreement") is dated as of July
10,  2003,  by and  among  Cytogen  Corporation,  a  Delaware  corporation  (the
"Company"),  and the purchasers identified on the signature pages hereto (each a
"Purchaser" and collectively the "Purchasers"); and

     WHEREAS,  subject to the terms and  conditions  set forth in this Agreement
and pursuant to Section 4(2) of the Securities Act (as defined below),  and Rule
506  promulgated  thereunder,  the  Company  desires  to  issue  and sell to the
Purchasers,  and the Purchasers,  severally and not jointly,  desire to purchase
from the Company in the aggregate,  up to  $10,000,000  of the Company's  Common
Stock and certain Warrants, as more fully described in this Agreement.

     NOW, THEREFORE,  IN CONSIDERATION of the mutual covenants contained in this
Agreement,  and for  other  good and  valuable  consideration  the  receipt  and
adequacy of which are hereby acknowledged, the Company and each Purchaser agrees
as follows:

                                   ARTICLE I.
                                  DEFINITIONS

     1.1  Definitions.  In  addition  to the  terms  defined  elsewhere  in this
Agreement,  for all purposes of this  Agreement,  the  following  terms have the
meanings indicated in this Section 1.1:

               "Action" shall have the meaning  ascribed to such term in Section
          3.1(j).

               "Affiliate" means any Person that, directly or indirectly through
          one or more  intermediaries,  controls or is controlled by or is under
          common  control with a Person as such terms are used in and  construed
          under Rule 144. With respect to a Purchaser,  any  investment  fund or
          managed account that is managed on a  discretionary  basis by the same
          investment manager as such Purchaser will be deemed to be an Affiliate
          of such Purchaser.

               "Business Day" means any day except Saturday,  Sunday and any day
          which  shall be a  federal  legal  holiday  or a day on which  banking
          institutions  in the State of Delaware are  authorized  or required by
          law or other governmental action to close.

               "Closing"  means  the  closing  of the  purchase  and sale of the
          Common Stock and Warrants pursuant to Section 2.1.

               "Closing Date" means the date of the Closing.

               "Commission"  means  the  Securities  and  Exchange   Commission.

               "Common  Stock" means the common stock of the Company,  $0.01 par
          value per share,  and any securities  into which such common stock may
          hereafter be reclassified.

<PAGE>


               "Common Stock Equivalents" means any securities of the Company or
          the Subsidiaries  which would entitle the holder thereof to acquire at
          any  time  Common  Stock,  including  without  limitation,  any  debt,
          preferred stock, rights, options, warrants or other instrument that is
          at any  time  convertible  into  or  exchangeable  for,  or  otherwise
          entitles the holder thereof to receive, Common Stock.

               "Company  Counsel"  means  Hale  and  Dorr  LLP,  counsel  to the
          Company.

               "Disclosure    Schedules"   means   the   Disclosure    Schedules
          concurrently delivered herewith.

               "Disclosure  Materials"  shall have the meaning  ascribed to such
          term in Section 3.1(h).

               "Effective Date" means the date that the  Registration  Statement
          is first declared effective by the Commission.

               "Exchange  Act" means the  Securities  Exchange  Act of 1934,  as
          amended.

               "Intellectual Property Rights" shall have the meaning ascribed to
          such term in Section 3.1(o).

               "Liens" means a lien,  charge,  security  interest,  encumbrance,
          right of first refusal or other restriction.

               "Material Adverse Effect" shall have the meaning ascribed to such
          term in Section 3.1(b).

               "Material  Permits" shall have the meaning  ascribed to such term
          in Section 3.1(m).

               "Per Share Purchase Price" equals $8.53.

               "Person" means an individual or corporation,  partnership, trust,
          incorporated or  unincorporated  association,  joint venture,  limited
          liability  company,  joint stock company,  government (or an agency or
          subdivision thereof) or other entity of any kind.

               "Registration  Statement" means a registration  statement meeting
          the requirements  set forth in the  Registration  Rights Agreement and
          covering  the resale by the  Purchasers  of the Shares and the Warrant
          Shares.

               "Registration  Rights  Agreement" means the  Registration  Rights
          Agreement,  dated as of the date of this  Agreement,  by and among the
          Company and the Purchasers, in the form of Exhibit B hereto.

               "Rule 144," means Rule 144 promulgated by the Commission pursuant
          to the Securities Act, as such Rules may be amended from time to time,
          or any similar rule or regulation  hereafter adopted by the Commission
          having substantially the same effect as such Rule.

                                      -2-


<PAGE>


               "SEC  Reports"  shall have the  meaning  ascribed to such term in
          Section 3.1(h).

               "Securities"  means the  Shares,  the  Warrants  and the  Warrant
          Shares.

               "Securities Act" means the Securities Act of 1933, as amended.

               "Shares"  means the shares of Common  Stock issued or issuable to
          each Purchaser pursuant to this Agreement.

               "Subscription  Amount" means, as to each  Purchaser,  the amounts
          set forth below such Purchaser's signature block on the signature page
          hereto, in United States dollars and in immediately available funds.

               "Subsidiary"  shall  have the  meaning  ascribed  to such term in
          Section 3.1(a).

               "Trading Day" means (i) a day on which the Common Stock is traded
          on a Trading  Market,  or (ii) if the Common  Stock is not listed on a
          Trading  Market,  a day on which  the  Common  Stock is  traded on the
          over-the-counter  market,  as reported by the OTC Bulletin  Board,  or
          (iii) if the Common Stock is not quoted on the OTC Bulletin  Board,  a
          day on which the Common Stock is quoted in the over-the-counter market
          as reported by the  National  Quotation  Bureau  Incorporated  (or any
          similar  organization or agency  succeeding its functions of reporting
          prices);  provided,  that in the event  that the  Common  Stock is not
          listed  or quoted as set  forth in (i),  (ii) and (iii)  hereof,  then
          Trading Day shall mean a Business Day.

               "Trading  Market"  means the  following  markets or  exchanges on
          which the Common  Stock is listed or quoted for trading on the date in
          question:  the American Stock  Exchange,  the New York Stock Exchange,
          the Nasdaq National Market or the Nasdaq SmallCap Market.

               "Transaction  Documents"  means this Agreement,  the Registration
          Rights  Agreement,  the Warrants and any other documents or agreements
          executed in connection with the transactions contemplated hereunder.

               "Warrants" means the Common Stock Purchase Warrants,  in the form
          of Exhibit C, issuable to the  Purchasers at the Closing,  with a term
          of exercise of 5 years  beginning  immediately  upon  issuance  and an
          exercise price equal to $12.80, subject to adjustment therein.

               "Warrant  Shares" means the shares of Common Stock  issuable upon
          exercise of the Warrants.

                                   ARTICLE II.
                                PURCHASE AND SALE

     2.1 Closing. At the Closing,  the Purchasers shall purchase,  severally and
not  jointly,  and the Company  shall issue and sell,  in the  aggregate,  up to
$10,000,000 of Common Stock,  together with the Warrants.  Each Purchaser  shall
purchase  from  the  Company,  and the  Company  shall  issue  and  sell to each
Purchaser,  (a) a number of Shares equal to such Purchaser's

                                      -3-
<PAGE>


Subscription Amount divided by the Per Share Purchase Price and (b) the Warrants
as determined pursuant to Section 2.2(a).

     2.2 Closing Conditions.

          (a) At the Closing (unless  otherwise  specified  below),  the Company
     shall deliver or cause to be delivered to each Purchaser the following:

               (i) this Agreement duly executed by the Company;

               (ii)  within  5  Trading  Days  of  the  Closing,  a  certificate
          evidencing   that   number  of  Shares   equal  to  such   Purchaser's
          Subscription   Amount  divided  by  the  Per  Share  Purchase   Price,
          registered in the name of such Purchaser;

               (iii) a legal opinion of Company Counsel,  in the form of Exhibit
          A hereto, addressed to the Purchasers;

               (iv) the  Registration  Rights  Agreement  duly  executed  by the
          Company; and

               (v) a Warrant, registered in the name of such Purchaser, pursuant
          to which  such  Purchaser  shall  have the right to  acquire up to the
          number of shares of  Common  Stock  equal to 100% of the  Shares to be
          issued to such Purchaser at the Closing.

          (b) At the  Closing  each  Purchaser  shall  deliver  or  cause  to be
     delivered to the Company the following:

               (i) this Agreement duly executed by such;

               (ii) such Purchaser's Subscription Amount by wire transfer to the
          account of the Company per the written  instructions  of the  Company;
          and

               (iii) the  Registration  Rights  Agreement  duly executed by such
          Purchaser.

          (c) As of the Closing Date,  there shall have been no Material Adverse
     Effect with respect to the Company since the date hereof.

          (d) As of the Closing Date, trading in the Common Stock shall not have
     been suspended by the  Commission  (except for any suspension of trading of
     limited  duration  agreed  to by the  Company,  which  suspension  shall be
     terminated prior to the Closing).

                                  ARTICLE III.
                         REPRESENTATIONS AND WARRANTIES

     3.1  Representations  and  Warranties  of the Company.  Except as set forth
under the corresponding  section of the Disclosure  Schedules or as set forth in
the SEC Reports,  the Company  hereby makes the  following  representations  and
warranties as of the date hereof to each Purchaser:

                                      -4-
<PAGE>


          (a) Subsidiaries.  The Company has no direct or indirect  subsidiaries
     ("Subsidiaries").  The Company  owns,  directly or  indirectly,  all of the
     capital  stock of each  Subsidiary  free and  clear  of any  lien,  charge,
     security interest, encumbrance, right of first refusal or other restriction
     (collectively,  "Liens"),  and all the  issued  and  outstanding  shares of
     capital  stock of each  Subsidiary  are validly  issued and are fully paid,
     nonassessable and free of preemptive and similar rights.

          (b)  Organization  and  Qualification.  Each  of the  Company  and the
     Subsidiaries is an entity duly incorporated or otherwise organized, validly
     existing and in good  standing  under the laws of the  jurisdiction  of its
     incorporation or organization (as applicable), with the requisite power and
     authority  to own and use its  properties  and  assets  and to carry on its
     business as currently conducted.  Neither the Company nor any Subsidiary is
     in violation of any of the  provisions  of its  respective  certificate  or
     articles  of  incorporation,  bylaws  or other  organizational  or  charter
     documents.  Each of the Company and the  Subsidiaries  is duly qualified to
     conduct business and is in good standing as a foreign  corporation or other
     entity in each  jurisdiction in which the nature of the business  conducted
     or property owned by it makes such  qualification  necessary,  except where
     the failure to be so  qualified  or in good  standing,  as the case may be,
     would not have or  reasonably  be  expected  to  result  in (i) a  material
     adverse  effect  on  the  legality,   validity  or  enforceability  of  any
     Transaction  Document,  (ii) a material  adverse  effect on the  results of
     operations,  assets, business or financial condition of the Company and the
     Subsidiaries,  taken as a whole,  or (iii)  adversely  impair the Company's
     ability  to  perform  in  any  material  respect  on  a  timely  basis  its
     obligations  under any  Transaction  Document (any of (i), (ii) or (iii), a
     "Material Adverse Effect").

          (c)  Authorization;   Enforcement.   The  Company  has  the  requisite
     corporate  power  and  authority  to  enter  into  and  to  consummate  the
     transactions   contemplated  by  each  of  the  Transaction  Documents  and
     otherwise  to carry  out its  obligations  thereunder.  The  execution  and
     delivery  of each  of the  Transaction  Documents  by the  Company  and the
     consummation by it of the transactions  contemplated thereby have been duly
     authorized  by all  necessary  action  on the  part of the  Company  and no
     further  action is required by the Company in  connection  therewith.  Each
     Transaction  Document  has been (or upon  delivery  will  have  been)  duly
     executed by the Company and, when  delivered in  accordance  with the terms
     hereof,  will  constitute  the valid and binding  obligation of the Company
     enforceable  against the Company in accordance with its terms except (i) as
     limited by applicable bankruptcy,  insolvency,  reorganization,  moratorium
     and other laws of general application  affecting  enforcement of creditors'
     rights  generally and (ii) as limited by laws relating to the  availability
     of specific performance, injunctive relief or other equitable remedies.

          (d) No  Conflicts.  The  execution,  delivery and  performance  of the
     Transaction Documents by the Company and the consummation by the Company of
     the transactions contemplated thereby do not and will not (i) conflict with
     or violate any provision of the Company's or any  Subsidiary's  certificate
     or articles of  incorporation,  bylaws or other  organizational  or charter
     documents, or (ii) conflict with, or constitute a default (or an event that
     with notice or lapse of time or both would become a default) under, or give
     to  others  any  rights  of   termination,   amendment,   acceleration   or
     cancellation  (with or  without  notice,  lapse of time or  both)  of,  any
     agreement,  credit facility, debt or other

                                      -5-
<PAGE>

     instrument  (evidencing a Company or Subsidiary debt or otherwise) or other
     understanding to which the Company or any Subsidiary is a party or by which
     any  property  or  asset  of the  Company  or any  Subsidiary  is  bound or
     affected,  or (iii)  result in a violation  of any law,  rule,  regulation,
     order,  judgment,  injunction,  decree or other restriction of any court or
     governmental  authority  to which the  Company or a  Subsidiary  is subject
     (including federal and state securities laws and regulations),  or by which
     any property or asset of the Company or a Subsidiary  is bound or affected;
     except in the case of each of  clauses  (ii) and  (iii),  such as would not
     have or reasonably be expected to result in a Material Adverse Effect.

          (e) Filings,  Consents and  Approvals.  The Company is not required to
     obtain any consent, waiver,  authorization or order of, give any notice to,
     or make any filing or registration with, any court or other federal, state,
     local or other  governmental  authority or other Person in connection  with
     the execution,  delivery and  performance by the Company of the Transaction
     Documents,   other  than  (a)  the  filing  with  the   Commission  of  the
     Registration  Statement,  the application(s) to each Trading Market for the
     listing of the Shares and Warrant  Shares for  trading  thereon in the time
     and manner required thereby, and applicable Blue Sky filings; (b) obtaining
     consent from its Trading Market to consummate the transaction without prior
     stockholder  approval;  or (c) such as have already  been  obtained or such
     exemptive  filings as are required to be made under  applicable  securities
     laws.

          (f) Issuance of the Securities. The Securities are duly authorized and
     the Shares and Warrant Shares,  when issued and paid for in accordance with
     the Transaction Documents,  will be duly and validly issued, fully paid and
     nonassessable,  free and clear of all Liens.  The Company has reserved from
     its duly authorized  capital stock,  the maximum number of shares of Common
     Stock issuable pursuant to this Agreement and the Warrants.

          (g) Capitalization.  The capitalization of the Company is as described
     in the Company's most recent  periodic  report filed with the Commission as
     updated by any current  report filed with the  Commission  thereafter.  The
     Company has not issued any  capital  stock  since such  filings  other than
     pursuant to the  exercise of employee  stock  options  under the  Company's
     stock  option  plans,  the  issuance of shares of Common Stock to employees
     pursuant to the Company's  employee stock  purchase  plan,  pursuant to the
     conversion or exercise of outstanding Common Stock Equivalents and pursuant
     to publicly disclosed equity  financings.  No Person has any right of first
     refusal, preemptive right, right of participation,  or any similar right to
     participate in the transactions  contemplated by the Transaction Documents.
     Except as a result of the purchase and sale of the Securities, there are no
     outstanding  options,  warrants,  script  rights to subscribe  to, calls or
     commitments of any character whatsoever relating to, or securities,  rights
     or obligations  convertible into or exchangeable  for, or giving any Person
     any right to  subscribe  for or  acquire,  any shares of Common  Stock,  or
     contracts, commitments, understandings or arrangements by which the Company
     or any  Subsidiary  is or may become  bound to issue  additional  shares of
     Common Stock,  or securities or rights  convertible  or  exchangeable  into
     shares of Common  Stock.  The  issue  and sale of the  Securities  will not
     obligate the Company to issue shares of Common Stock or other securities to
     any Person  (other than the  Purchasers)  and will not result in a right of
     any

                                      -6-
<PAGE>

     holder of Company securities to adjust the exercise,  conversion,  exchange
     or reset price under such securities.

          (h) SEC  Reports;  Financial  Statements.  The  Company  has filed all
     reports  required  to be  filed  by it  under  the  Securities  Act and the
     Exchange Act, including pursuant to Section 13(a) or 15(d) thereof, for the
     three  years  preceding  the date  hereof  (or such  shorter  period as the
     Company  was  required  by  law  to  file  such  material)  (the  foregoing
     materials,  including the exhibits  thereto and  incorporated  by reference
     therein,  being  collectively  referred to herein as the "SEC Reports" and,
     together with the Disclosure  Schedules to this Agreement,  the "Disclosure
     Materials")  on a timely  basis or has  received a valid  extension of such
     time of filing and has filed any such SEC Reports  prior to the  expiration
     of any  such  extension.  As of their  respective  dates,  the SEC  Reports
     complied in all material  respects with the  requirements of the Securities
     Act and the Exchange Act and the rules and  regulations  of the  Commission
     promulgated thereunder,  and none of the SEC Reports, when filed, contained
     any untrue statement of a material fact or omitted to state a material fact
     required to be stated  therein or necessary in order to make the statements
     therein,  in light of the  circumstances  under  which they were made,  not
     misleading.  The financial  statements  of the Company  included in the SEC
     Reports  comply  in  all  material  respects  with  applicable   accounting
     requirements  and the rules and  regulations of the Commission with respect
     thereto as in effect at the time of filing. Such financial  statements have
     been prepared in accordance with generally accepted  accounting  principles
     applied on a consistent basis during the periods involved ("GAAP"),  except
     as may be otherwise  specified in such  financial  statements  or the notes
     thereto and except that unaudited financial  statements may not contain all
     footnotes required by GAAP, and fairly present in all material respects the
     financial  position of the Company and its consolidated  subsidiaries as of
     and for the dates thereof and the results of operations  and cash flows for
     the periods then ended,  subject, in the case of unaudited  statements,  to
     normal year-end audit adjustments.

          (i) Material  Changes.  Since the date of the latest audited financial
     statements  included  within the SEC Reports,  (i) there has been no event,
     occurrence or development that has had or that could reasonably be expected
     to result in a Material  Adverse Effect,  (ii) the Company has not incurred
     any liabilities (contingent or otherwise) other than (A) trade payables and
     accrued  expenses  incurred in the ordinary  course of business  consistent
     with past practice and (B)  liabilities not required to be reflected in the
     Company's financial statements pursuant to GAAP or required to be disclosed
     in filings made with the Commission,  (iii) the Company has not altered its
     method  of  accounting,  (iv)  the  Company  has not  declared  or made any
     dividend or distribution  of cash or other property to its  stockholders or
     purchased, redeemed or made any agreements to purchase or redeem any shares
     of its capital stock; (v) the Company has not issued any equity  securities
     to any officer, director or Affiliate,  except pursuant to existing Company
     stock option plans; and (vi) the Company has not had any disagreement  with
     its independent auditors that would require public disclosure.

          (j)  Litigation.   There  is  no  action,  suit,  inquiry,  notice  of
     violation,  proceeding or investigation pending or, to the knowledge of the
     Company, threatened against or affecting the Company, any Subsidiary or any
     of  their  respective  properties  before  or  by  any  court,  arbitrator,
     governmental or administrative agency or regulatory authority

                                      -7-
<PAGE>


     (federal,  state,  county,  local or foreign)  (collectively,  an "Action")
     which (i)  adversely  affects  or  challenges  the  legality,  validity  or
     enforceability  of any of the  Transaction  Documents or the  Securities or
     (ii) could,  if there were an unfavorable  decision,  have or reasonably be
     expected to result in a Material  Adverse  Effect.  Neither the Company nor
     any  Subsidiary,  nor any director or officer  thereof,  is or has been the
     subject of any Action  involving a claim of violation of or liability under
     federal or state  securities  laws or a claim of breach of fiduciary  duty.
     There has not  been,  and to the  knowledge  of the  Company,  there is not
     pending or contemplated,  any investigation by the Commission involving the
     Company or any current or former  director or officer of the  Company.  The
     Commission  has not  issued any stop order or other  order  suspending  the
     effectiveness  of any  registration  statement  filed by the Company or any
     Subsidiary under the Exchange Act or the Securities Act.

          (k) Labor  Relations.  No  material  labor  dispute  exists or, to the
     knowledge of the Company,  is imminent with respect to any of the employees
     of the Company  which could  reasonably be expected to result in a Material
     Adverse Effect.

          (l)  Compliance.  Neither  the Company  nor any  Subsidiary  (i) is in
     default  under or in violation  of (and no event has occurred  that has not
     been waived that,  with notice or lapse of time or both,  would result in a
     default by the Company or any Subsidiary under), nor has the Company or any
     Subsidiary  received  notice of a claim that it is in default under or that
     it is in violation of, any indenture, loan or credit agreement or any other
     agreement or instrument to which it is a party or by which it or any of its
     properties  is bound  (whether or not such  default or  violation  has been
     waived),  (ii) is in  violation  of any order of any court,  arbitrator  or
     governmental  body,  or (iii) is or has been in  violation  of any statute,
     rule  or  regulation  of  any  governmental  authority,  including  without
     limitation  all foreign,  federal,  state and local laws  applicable to its
     business,  except in the case of clauses  (i),  (ii) and (iii) as would not
     have or reasonably be expected to result in a Material Adverse Effect.

          (m) Regulatory Permits.  The Company and the Subsidiaries  possess all
     certificates, authorizations and permits issued by the appropriate federal,
     state, local or foreign regulatory  authorities  necessary to conduct their
     respective  businesses  as described  in the SEC Reports,  except where the
     failure to possess such permits would not have or reasonably be expected to
     result in a Material Adverse Effect ("Material  Permits"),  and neither the
     Company nor any Subsidiary has received any notice of proceedings  relating
     to the revocation or modification of any Material Permit.

          (n) Title to Assets.  The Company and the  Subsidiaries  have good and
     marketable  title in fee simple to all real property  owned by them that is
     material to the business of the Company and the  Subsidiaries  and good and
     marketable title in all personal property owned by them that is material to
     the  business of the Company  and the  Subsidiaries,  in each case free and
     clear of all Liens,  except for Liens as do not materially affect the value
     of such  property  and do not  materially  interfere  with the use made and
     proposed to be made of such  property  by the Company and the  Subsidiaries
     and Liens for the payment of federal,  state or other taxes, the payment of
     which is neither delinquent nor subject to penalties. Any real property and
     facilities held under lease by the

                                      -8-
<PAGE>

     Company and the Subsidiaries  are held by them under valid,  subsisting and
     enforceable  leases  of  which  the  Company  and the  Subsidiaries  are in
     compliance.

          (o) Patents and  Trademarks.  To the knowledge of the Company and each
     Subsidiary,  the Company and the Subsidiaries  have, or have rights to use,
     all  patents,  patent  applications,  trademarks,  trademark  applications,
     service marks, trade names,  copyrights,  licenses and other similar rights
     that are necessary or material for use in connection with their  respective
     businesses as described in the SEC Reports and which the failure to so have
     could have or reasonably be expected to result in a Material Adverse Effect
     (collectively, the "Intellectual Property Rights"). Neither the Company nor
     any Subsidiary has received a written notice that the Intellectual Property
     Rights used by the Company or any Subsidiary violates or infringes upon the
     rights  of  any  Person.  To  the  knowledge  of  the  Company,   all  such
     Intellectual Property Rights are enforceable.

          (p)  Insurance.  The  Company  and the  Subsidiaries  are  insured  by
     insurers of  recognized  financial  responsibility  against such losses and
     risks and in such amounts as are prudent and customary in the businesses in
     which the Company and the Subsidiaries are engaged. Neither the Company nor
     any  Subsidiary has any reason to believe that it will not be able to renew
     its existing  insurance  coverage as and when such  coverage  expires or to
     obtain  similar  coverage  from  similar  insurers as may be  necessary  to
     continue its business without a significant increase in cost.

          (q) Transactions  With Affiliates and Employees.  None of the officers
     or directors of the Company and, to the  knowledge of the Company,  none of
     the employees of the Company is presently a party to any  transaction  with
     the  Company or any  Subsidiary  (other  than for  services  as  employees,
     officers  and  directors),  including  any  contract,  agreement  or  other
     arrangement  providing for the  furnishing of services to or by,  providing
     for rental of real or personal property to or from, or otherwise  requiring
     payments  to or from any  officer,  director  or such  employee  or, to the
     knowledge of the Company, any entity in which any officer, director, or any
     such  employee  has a  substantial  interest  or is an  officer,  director,
     trustee or  partner,  in each case in excess of $60,000  other than (a) for
     payment  of  salary  or  consulting   fees  for  services   rendered,   (b)
     reimbursement  for  expenses  incurred on behalf of the Company and (c) for
     other employee benefits,  including stock option agreements under any stock
     option plan of the Company.

          (r)  Internal  Accounting  Controls.  The  Company  and  each  of  its
     subsidiaries  maintains a system of internal accounting controls sufficient
     to provide  reasonable  assurance  that (i)  transactions  are  executed in
     accordance  with  management's  general or  specific  authorizations,  (ii)
     transactions  are recorded as necessary to permit  preparation of financial
     statements in conformity  with GAAP and to maintain  asset  accountability,
     (iii) access to assets is permitted  only in accordance  with  management's
     general or specific authorization, and (iv) the recorded accountability for
     assets is compared  with the existing  assets at  reasonable  intervals and
     appropriate  action is taken with respect to any  differences.  The Company
     has established  disclosure controls and procedures (as defined in Exchange
     Act Rules 13a-14 and 15d-14) for the Company and designed such  disclosures
     controls and procedures to ensure that material information relating to the
     Company,  including  its  subsidiaries,  is made  known  to the  certifying
     officers by others

                                      -9-
<PAGE>

     within  those  entities,  particularly  during  the  period  in  which  the
     Company's  Form 10-K or 10-Q,  as the case may be, is being  prepared.  The
     Company's  certifying  officers  have  evaluated the  effectiveness  of the
     Company's  controls and procedures as of a date within 90 days prior to the
     filing  date of the Form 10-K for the fiscal year ended  December  31, 2002
     (such date,  the  "Evaluation  Date").  The Company  presented  in its most
     recently  filed Form 10-K or Form 10-Q the  conclusions  of the  certifying
     officers about the effectiveness of the disclosure  controls and procedures
     based on their  evaluations as of the Evaluation Date. Since the Evaluation
     Date,  there have been no  significant  changes in the  Company's  internal
     controls  (as such term is defined in Item 307(b) of  Regulation  S-K under
     the Exchange  Act) or, to the  Company's  knowledge,  in other factors that
     could significantly affect the Company's internal controls.

          (s) Certain Fees. No brokerage or finder's fees or commissions  are or
     will  be  payable  by the  Company  to any  broker,  financial  advisor  or
     consultant,  finder,  placement  agent,  investment  banker,  bank or other
     Person with respect to the transactions contemplated by this Agreement. The
     Purchasers  shall  have no  obligation  with  respect  to any  fees or with
     respect to any claims  made by or on behalf of other  Persons for fees of a
     type  contemplated  in this Section that may be due in connection  with the
     transactions contemplated by this Agreement.

          (t)  Private  Placement.  Assuming  the  accuracy  of  the  Purchasers
     representations  and warranties  set forth in Section 3.2, no  registration
     under  the  Securities  Act is  required  for  the  offer  and  sale of the
     Securities by the Company to the Purchasers as contemplated hereby.

          (u)  Investment  Company.  The Company is not, and is not an Affiliate
     of, an "investment  company"  within the meaning of the Investment  Company
     Act of 1940, as amended.

          (v) Registration  Rights. No Person has any right to cause the Company
     to effect the  registration  under the  Securities Act of any securities of
     the Company.

          (w) Listing and Maintenance Requirements.  The Company has not, in the
     12 months  preceding  the date  hereof,  received  notice  from any Trading
     Market on which  the  Common  Stock is or has been  listed or quoted to the
     effect  that  the  Company  is  not  in  compliance  with  the  listing  or
     maintenance requirements of such Trading Market. The Company is, and has no
     reason to believe that it will not in the  foreseeable  future  continue to
     be, in compliance with all such listing and maintenance requirements.

          (x) Application of Takeover Protections.  The Company and its Board of
     Directors  have  taken all  necessary  action,  if any,  in order to render
     inapplicable any control share acquisition,  business  combination,  poison
     pill (including any distribution under a rights agreement) or other similar
     anti-takeover  provision under the Company's  Certificate of  Incorporation
     (or similar  charter  documents) or the laws of its state of  incorporation
     that is or could become  applicable  to the  Purchasers  as a result of the
     Purchasers and the Company fulfilling their obligations or exercising their
     rights under the Transaction  Documents,  including without  limitation the
     Company's  issuance of the Securities and the Purchasers'  ownership of the
     Securities.

                                      -10-
<PAGE>

          (y)  Disclosure.  The Company  confirms  that,  except as provided for
     herein,  neither the Company nor any other Person  acting on its behalf has
     provided  any of the  Purchasers  or  their  agents  or  counsel  with  any
     information  that  constitutes  or might  constitute  material,  non-public
     information.  The Company understands and confirms that the Purchasers will
     rely  on  the   foregoing   representations   and  covenants  in  effecting
     transactions  in  securities  of the  Company.  Subject to Section  3.2(h),
     neither this  Agreement,  nor any Exhibit  attached  hereto provided to the
     Purchasers  regarding  the  Company,  its  business  and  the  transactions
     contemplated hereby,  including the Disclosure Schedules to this Agreement,
     furnished  by or on behalf of the  Company  are true and correct and do not
     contain  any  untrue  statement  of a  material  fact or omit to state  any
     material fact  necessary in order to make the statements  made therein,  in
     light of the circumstances under which they were made, not misleading.

     3.2  Representations  and  Warranties  of the  Purchasers.  Each  Purchaser
hereby, for itself and for no other Purchaser, represents and warrants as of the
date hereof and as of the Closing Date to the Company as follows:

          (a)  Organization;   Authority.  Such  Purchaser  is  an  entity  duly
     organized,  validly  existing  and in good  standing  under the laws of the
     jurisdiction of its organization with full right,  corporate or partnership
     power  and  authority  to enter  into and to  consummate  the  transactions
     contemplated  by the  Transaction  Documents and otherwise to carry out its
     obligations  thereunder.  The execution,  delivery and  performance by such
     Purchaser of the transactions  contemplated by this Agreement has been duly
     authorized by all necessary corporate action on the part of such Purchaser.
     Each  Transaction  Document to which it is party has been duly  executed by
     such  Purchaser,  and when delivered by such  Purchaser in accordance  with
     terms hereof,  will constitute the valid and legally binding  obligation of
     such Purchaser, enforceable against it in accordance with its terms.

          (b) Investment Intent. Such Purchaser  understands that the Securities
     are  "restricted  securities"  and  have  not  been  registered  under  the
     Securities Act or any applicable  state securities law and is acquiring the
     Securities  as principal for its own account for  investment  purposes only
     and not with a view to or for  distributing or reselling such Securities or
     any part  thereof,  has no present  intention of  distributing  any of such
     Securities and has no arrangement or  understanding  with any other persons
     regarding the  distribution of such  Securities  (this  representation  and
     warranty  not  limiting  such  Purchaser's  right  to sell  the  Securities
     pursuant to the  Registration  Statement or otherwise  in  compliance  with
     applicable  federal and state securities laws). Such Purchaser is acquiring
     the  Securities  hereunder in the  ordinary  course of its  business.  Such
     Purchaser  does  not have  any  agreement  or  understanding,  directly  or
     indirectly, with any Person to distribute any of the Securities.

          (c)  Purchaser  Status.  At the time such  Purchaser  was  offered the
     Securities,  it was, and at the date hereof it is an "accredited  investor"
     as defined in Rule 501(a) under the Securities  Act. Such Purchaser (if not
     already a registered broker-dealer under Section 15 of the Exchange Act) is
     not required to be  registered as a  broker-dealer  under Section 15 of the
     Exchange Act.

                                      -11-
<PAGE>


          (d)  Experience of such  Purchaser.  Such  Purchaser,  either alone or
     together with its representatives,  has such knowledge,  sophistication and
     experience  in  business  and  financial  matters  so as to be  capable  of
     evaluating  the  merits  and  risks of the  prospective  investment  in the
     Securities,  and has so evaluated the merits and risks of such  investment.
     Such  Purchaser is able to bear the economic  risk of an  investment in the
     Securities  and, at the present  time, is able to afford a complete loss of
     such investment.

          (e)  General  Solicitation.  Such  Purchaser  is  not  purchasing  the
     Securities  as a result  of any  advertisement,  article,  notice  or other
     communication regarding the Securities published in any newspaper, magazine
     or similar media or broadcast over  television or radio or presented at any
     seminar or any other general solicitation or general advertisement.

          (f) Certain Fees. No brokerage or finder's fees or commissions  are or
     will be payable  by such  Purchaser  to any  broker,  financial  advisor or
     consultant,  finder,  placement  agent,  investment  banker,  bank or other
     Person with respect to the transactions contemplated by this Agreement. The
     Company shall have no  obligation  with respect to any fees or with respect
     to any  claims  made by or on  behalf of other  Persons  for fees of a type
     contemplated  in  this  Section  that  may be due in  connection  with  the
     transactions contemplated by this Agreement.

          (g)  Acquiring  Person.  Such  Purchaser,  after giving  effect to the
     transactions  contemplated  hereby, will not, either individually or with a
     group  (as  defined  in  Section  13(d)(3)  of the  Exchange  Act),  be the
     beneficial owner of 20% or more of the Company's  outstanding Common Stock.
     For  purposes  of  this  Section  3.2(g),  beneficial  ownership  shall  be
     determined pursuant to a Rule 13d-3 under the Exchange Act.

          (h) Material Information. Such Purchaser acknowledges that the Company
     may have  material  non-public  information  with  respect to,  among other
     things,  the Company's results of operations for the quarter ended June 30,
     2003  that  has  not  yet  been  publicly  disclosed  or  disclosed  in the
     Disclosure  Materials.  Such Purchaser  acknowledges  that it has requested
     that the Company not disclose such information to it.

     The Company  acknowledges  and agrees that each  Purchaser does not make or
has not made any  representations or warranties with respect to the transactions
contemplated hereby other than those specifically set forth in this Section 3.2.

                                  ARTICLE IV.
                        OTHER AGREEMENTS OF THE PARTIES

     4.1 Transfer  Restrictions.  (a) The  Securities may only be disposed of in
compliance  with state and  federal  securities  laws.  In  connection  with any
transfer  of  Securities  other  than  pursuant  to  an  effective  registration
statement,  to the Company, to an Affiliate of a Purchaser or in connection with
a pledge as  contemplated  in  Section  4.1(b),  the  Company  may  require  the
transferor  thereof to provide to the Company an opinion of counsel  selected by
the  transferor,  the form and  substance of which  opinion  shall be reasonably
satisfactory  to the Company,  to the effect that such transfer does not require
registration  of such  transferred  Securities  under the  Securities  Act. As a
condition of transfer, any such transferee shall agree in writing to be bound by
the terms of this Agreement and

                                      -12-
<PAGE>

     shall  have  the  rights  of a  Purchaser  under  this  Agreement  and  the
     Registration Rights Agreement.

          (b) The Purchasers agree to the imprinting,  so long as is required by
     this Section 4.1(b),  of a legend on any of the Securities in the following
     form:

          THESE  SECURITIES  HAVE NOT BEEN  REGISTERED  WITH THE  SECURITIES AND
          EXCHANGE  COMMISSION  OR THE  SECURITIES  COMMISSION  OF ANY  STATE IN
          RELIANCE UPON AN EXEMPTION FROM REGISTRATION  UNDER THE SECURITIES ACT
          OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND, ACCORDINGLY,  MAY NOT
          BE  OFFERED  OR SOLD  EXCEPT  PURSUANT  TO AN  EFFECTIVE  REGISTRATION
          STATEMENT  UNDER  THE  SECURITIES  ACT  OR  PURSUANT  TO AN  AVAILABLE
          EXEMPTION FROM, OR IN A TRANSACTION  NOT SUBJECT TO, THE  REGISTRATION
          REQUIREMENTS  OF THE SECURITIES ACT AND IN ACCORDANCE  WITH APPLICABLE
          STATE  SECURITIES  LAWS AS EVIDENCED BY A LEGAL  OPINION OF COUNSEL TO
          THE  TRANSFEROR  TO SUCH  EFFECT,  THE  SUBSTANCE  OF  WHICH  SHALL BE
          REASONABLY ACCEPTABLE TO THE COMPANY.  THESE SECURITIES MAY BE PLEDGED
          IN  CONNECTION  WITH A BONA  FIDE  MARGIN  ACCOUNT  WITH A  REGISTERED
          BROKER-DEALER  OR OTHER LOAN WITH A FINANCIAL  INSTITUTION  THAT IS AN
          "ACCREDITED  INVESTOR" AS DEFINED IN RULE 501(a) UNDER THE  SECURITIES
          ACT.

          The Company  acknowledges and agrees that a Purchaser may from time to
     time  pledge  pursuant to a bona fide margin  agreement  with a  registered
     broker-dealer or grant a security interest in some or all of the Securities
     to a financial  institution that is an "accredited  investor" as defined in
     Rule 501(a) under the  Securities  Act and, if required  under the terms of
     such arrangement, such Purchaser may transfer pledged or secured Securities
     to the pledgees or secured parties.  Such a pledge or transfer would not be
     subject to approval of the Company and no legal opinion of legal counsel of
     the  pledgee,  secured  party or pledgor  shall be required  in  connection
     therewith.  Further,  no notice  shall be required of such  pledge.  At the
     appropriate  Purchaser's expense, the Company will execute and deliver such
     reasonable  documentation  as a pledgee or secured party of Securities  may
     reasonably  request  in  connection  with  a  pledge  or  transfer  of  the
     Securities, including the preparation and filing of any required prospectus
     supplement  under Rule 424(b)(3) of the Securities Act or other  applicable
     provision of the Securities Act to appropriately  amend the list of Selling
     Stockholders thereunder.

          (c)  Certificates  evidencing  the Shares and Warrant Shares shall not
     contain any legend (including the legend set forth in Section 4.1(b)),  (i)
     while a  registration  statement  (including  the  Registration  Statement)
     covering the resale of such security is effective  under the Securities Act
     and such security has been sold pursuant to such registration statement, or
     (ii) following any sale of such Shares or Warrant  Shares  pursuant to Rule
     144, or (iii) if such Shares or Warrant  Shares are eligible for sale under
     Rule  144(k),  or (iv) if such  legend  is not  required  under  applicable
     requirements of the Securities Act (including judicial  interpretations and
     pronouncements issued by the Staff

                                      -13-
<PAGE>


     of the  Commission).  The Company  shall cause its counsel to issue a legal
     opinion to the Company's  transfer  agent promptly after the Effective Date
     if required by the  Company's  transfer  agent to effect the removal of the
     legend  hereunder.  The Company agrees that following the Effective Date or
     at such time as such  legend  is no  longer  required  under  this  Section
     4.1(c), it will, no later than seven Trading Days following the delivery by
     a  Purchaser  to the  Company  or the  Company's  transfer  agent of: (i) a
     certificate  representing  Shares or  Warrant  Shares,  as the case may be,
     issued  with  a  restrictive  legend;  and  (ii)  any  other  documentation
     reasonably  requested  by the Company,  its counsel or its transfer  agent,
     deliver  or  cause  to  be  delivered  to  such   Purchaser  a  certificate
     representing  such  Securities  that is free from all restrictive and other
     legends.  The  Company  may not make any  notation  on its  records or give
     instructions  to  any  transfer  agent  of the  Company  that  enlarge  the
     restrictions on transfer set forth in this Section.

     4.2 Furnishing of  Information.  As long as any Purchaser owns  Securities,
the Company  covenants to timely file (or obtain  extensions in respect  thereof
and file within the applicable grace period) all reports required to be filed by
the Company after the date hereof pursuant to the Exchange Act. Upon the request
of any such holder of  Securities,  the Company  shall  deliver to such holder a
written certification of a duly authorized officer as to whether it has complied
with the preceding  sentence.  As long as any Purchaser owns Securities,  if the
Company is not required to file reports  pursuant to such laws,  it will prepare
and furnish to the  Purchasers  and make publicly  available in accordance  with
Rule  144(c) such  information  as is required  for the  Purchasers  to sell the
Securities under Rule 144. The Company further  covenants that it will take such
further action as any holder of Securities may  reasonably  request,  all to the
extent  required from time to time to enable such Person to sell such Securities
without  registration  under the  Securities  Act within the  limitation  of the
exemptions provided by Rule 144.

     4.3 Securities  Laws  Disclosure;  Publicity.  The Company shall,  within 3
Trading Days of the Closing Date, issue a press release or file a Current Report
on Form 8-K, in each case reasonably acceptable to each Purchaser disclosing the
transactions  contemplated hereby and make such other filings and notices in the
manner and time required by the Commission. The Company and each Purchaser shall
consult  with each  other in  issuing  any press  releases  with  respect to the
transactions  contemplated  hereby,  and neither  the Company nor any  Purchaser
shall issue any such press release or otherwise  make any such public  statement
without the prior  consent of the Company,  with respect to any press release of
any Purchaser,  or without the prior consent of each Purchaser,  with respect to
any press  release of the  Company,  which  consent  shall not  unreasonably  be
withheld,  except if such disclosure is required by relevant securities or other
laws, in which case the disclosing  party shall promptly provide the other party
with prior notice of such public statement or communication. Notwithstanding the
foregoing, the Company shall not publicly disclose the name of any Purchaser, or
include  the name of any  Purchaser  in any filing  with the  Commission  or any
regulatory  agency or Trading Market,  without the prior written consent of such
Purchaser,  except (i) as required by federal  securities law in connection with
the registration statement contemplated by the Registration Rights Agreement and
(ii)  to the  extent  such  disclosure  is  required  by law or  Trading  Market
regulations.

     4.4  Shareholders  Rights Plan. The Purchaser is not an "Acquiring  Person"
under any shareholders rights plan or similar plan or arrangement in effect.

                                      -14-
<PAGE>


     4.5 Future Sales of Common Stock. Subject to its fiduciary responsibilities
to its stockholders, the Company covenants and agrees that it will not issue any
of its Common Stock at a price less than the Per Share Purchase Price until such
time as the  Registration  Statement is declared  effective  by the  Commission;
provided, that, this Section 4.5 shall not apply to any issuance of Common Stock
pursuant to any  agreement  made prior to the Closing Date,  including,  but not
limited to, any warrant,  option or other security convertible into Common Stock
or any Common Stock issued  pursuant to any  employee  stock option plan,  stock
option plan for  non-employee  directors,  employee  stock  purchase plan or any
other plan that  provides  incentive  stock grants to the  Company's  employees,
directors, consultants or agents.

     4.6 Use of Proceeds.  The Company  shall use the net proceeds from the sale
of the Shares  hereunder to reacquire  the  marketing  rights to Quadramet  from
Berlex  Laboratories,  Inc.  ("Berlex")  pursuant  to that  certain  Termination
Agreement,  dated June 16,  2003,  by and  between  the  Company  and Berlex and
related  expenses and not for the  satisfaction  of any portion of the Company's
debt, to redeem any Company equity or equity-equivalent  securities or to settle
any outstanding litigation.

     4.7 Indemnification of Purchasers.  The Company will indemnify and hold the
Purchasers and their directors, officers, shareholders,  partners, employees and
agents  (each,  a  "Purchaser   Party")   harmless  from  any  and  all  losses,
liabilities,  obligations,  claims, contingencies,  damages, costs and expenses,
including all judgments, amounts paid in settlements, court costs and reasonable
attorneys'  fees and costs of  investigation  that any such Purchaser  Party may
suffer or incur as a result of or relating to any  misrepresentation,  breach or
inaccuracy, or any allegation by a third party that, if true, would constitute a
breach or inaccuracy,  of any of the representations,  warranties,  covenants or
agreements  made by the Company in this  Agreement  or in the other  Transaction
Documents.  The Company will reimburse  such Purchaser for its reasonable  legal
and other expenses  (including the cost of any  investigation,  preparation  and
travel in  connection  therewith)  incurred  in  connection  therewith,  as such
expenses are incurred.

     4.8  Reservation  of Common Stock.  As of the date hereof,  the Company has
reserved  and the Company  shall  continue to reserve and keep  available at all
times, free of preemptive  rights, a sufficient number of shares of Common Stock
for the  purpose of  enabling  the  Company  to issue  Shares  pursuant  to this
Agreement and Warrant Shares pursuant to any exercise of the Warrants.

     4.9 Listing of Common Stock.  The Company hereby agrees to use commercially
reasonable  efforts to maintain  the listing of the Common  Stock on the Trading
Market,  and as soon as  reasonably  practicable  following the Closing (but not
later than the earlier of the Effective  Date and the first  anniversary  of the
Closing Date) to list the  applicable  Shares and Warrant  Shares on the Trading
Market.  The Company further  agrees,  if the Company applies to have the Common
Stock traded on any other Trading  Market,  it will include in such  application
the  Shares  and the  Warrant  Shares,  and will  take such  other  action as is
necessary or desirable in the opinion of the  Purchasers to cause the Shares and
Warrant  Shares  to be listed  on such  other  Trading  Market  as  promptly  as
possible.  The Company will take all action reasonably necessary to continue the
listing and trading of its Common  Stock on a Trading  Market and will comply in

                                      -15-
<PAGE>

all respects with the Company's  reporting,  filing and other  obligations under
the bylaws or rules of the Trading Market.

                                    ARTICLE V.
                                  MISCELLANEOUS

     5.1 Entire Agreement. The Transaction Documents, together with the exhibits
and  schedules  thereto,  contain the entire  understanding  of the parties with
respect to the subject  matter  hereof and supersede  all prior  agreements  and
understandings, oral or written, with respect to such matters, which the parties
acknowledge  have been merged into such documents,  exhibits and schedules.  The
Disclosure  Schedules are  incorporated by reference  herein and are included as
part of the Transaction Documents.

     5.3  Notices.  Any and all notices or other  communications  or  deliveries
required or permitted to be provided  hereunder shall be in writing and shall be
deemed given and effective on the earliest of (a) the date of  transmission,  if
such notice or  communication is delivered via facsimile at the facsimile number
specified on the signature  pages hereto prior to 6:30 p.m. (New York City time)
on a Trading Day, (b) the next  Trading Day after the date of  transmission,  if
such notice or  communication is delivered via facsimile at the facsimile number
specified  on the  signature  pages hereto on a day that is not a Trading Day or
later than 6:30 p.m.  (New York City time) on any Trading  Day,  (c) the Trading
Day  following  the  date of  mailing,  if sent  by U.S.  nationally  recognized
overnight courier service,  or (d) upon actual receipt by the party to whom such
notice is required to be given. The address for such notices and  communications
shall be as set forth on the signature pages attached hereto.

     5.4  Amendments;  Waivers.  No provision of this Agreement may be waived or
amended except in a written instrument  signed, in the case of an amendment,  by
the Company and  Purchasers  holding a majority of the Shares sold hereunder or,
in the case of a  waiver,  by the party  against  whom  enforcement  of any such
waiver is  sought.  No waiver of any  default  with  respect  to any  provision,
condition or requirement  of this  Agreement  shall be deemed to be a continuing
waiver in the  future or a waiver of any  subsequent  default or a waiver of any
other  provision,  condition  or  requirement  hereof,  nor  shall  any delay or
omission of either  party to exercise any right  hereunder in any manner  impair
the exercise of any such right.

     5.5  Construction.  The headings  herein are for  convenience  only, do not
constitute a part of this  Agreement  and shall not be deemed to limit or affect
any of the provisions hereof. The language used in this Agreement will be deemed
to be the language chosen by the parties to express their mutual intent,  and no
rules of strict construction will be applied against any party.

     5.6 Successors and Assigns.  This Agreement shall be binding upon and inure
to the benefit of the parties and their  successors and permitted  assigns.  The
Company may not assign this  Agreement  or any rights or  obligations  hereunder
without the prior written  consent of each  Purchaser.  Any Purchaser may assign
any or all of its  rights  under  this  Agreement  to any  Person  to whom  such
Purchaser  assigns or transfers any Securities,  provided such transferee agrees
in  writing to be bound,  with  respect to the  transferred  Securities,  by the
provisions hereof that apply to the "Purchasers".

                                      -16-
<PAGE>

     5.7 No  Third-Party  Beneficiaries.  This  Agreement  is  intended  for the
benefit of the parties  hereto and their  respective  successors  and  permitted
assigns and is not for the benefit of, nor may any provision  hereof be enforced
by, any other Person.

     5.8 Governing  Law. All questions  concerning the  construction,  validity,
enforcement and interpretation of the Transaction Documents shall be governed by
and construed and enforced in accordance  with the internal laws of the State of
Delaware,  without  regard to the  principles of conflicts of law thereof.  Each
party  agrees  that  all  legal  proceedings   concerning  the  interpretations,
enforcement and defense of the  transactions  contemplated by this Agreement and
any other Transaction  Documents  (whether brought against a party hereto or its
respective affiliates,  directors, officers, shareholders,  employees or agents)
shall be commenced  exclusively  in the state and federal  courts sitting in the
State of Delaware. Each party hereto hereby irrevocably submits to the exclusive
jurisdiction  of the state and federal  courts  sitting in the State of Delaware
for the adjudication of any dispute hereunder or in connection  herewith or with
any transaction  contemplated hereby or discussed herein (including with respect
to  the  enforcement  of  the  any of the  Transaction  Documents),  and  hereby
irrevocably  waives, and agrees not to assert in any suit, action or proceeding,
any claim  that it is not  personally  subject to the  jurisdiction  of any such
court,  that such suit,  action or  proceeding  is  improper.  Each party hereto
hereby  irrevocably  waives personal  service of process and consents to process
being served in any such suit,  action or  proceeding  by mailing a copy thereof
via  registered  or  certified  mail or  overnight  delivery  (with  evidence of
delivery)  to such party at the  address in effect for  notices to it under this
Agreement  and agrees that such service  shall  constitute  good and  sufficient
service of process and notice thereof.  Nothing contained herein shall be deemed
to limit in any way any right to serve  process in any manner  permitted by law.
Each party hereto  (including its affiliates,  agents,  officers,  directors and
employees)  hereby  irrevocably  waives,  to the  fullest  extent  permitted  by
applicable  law,  any and all  right to trial  by jury in any  legal  proceeding
arising out of or relating to this  Agreement or the  transactions  contemplated
hereby.  If either party shall  commence an action or  proceeding to enforce any
provisions of a Transaction  Document,  then the prevailing party in such action
or proceeding  shall be reimbursed by the other party for its attorneys fees and
other  costs and  expenses  incurred  with the  investigation,  preparation  and
prosecution of such action or proceeding.

     5.9 Survival.  The  representations,  warranties,  agreements and covenants
contained  herein  shall  survive  the  Closing  for a period of 1 year from the
Closing Date.

     5.10 Execution. This Agreement may be executed in two or more counterparts,
all of which when taken  together shall be considered one and the same agreement
and shall become effective when  counterparts have been signed by each party and
delivered to the other  party,  it being  understood  that both parties need not
sign the same  counterpart.  In the event that any  signature  is  delivered  by
facsimile  transmission,  such  signature  shall  create  a  valid  and  binding
obligation  of the  party  executing  (or on  whose  behalf  such  signature  is
executed)  with the same force and effect as if such  facsimile  signature  page
were an original thereof.

     5.11 Severability. If any provision of this Agreement is held to be invalid
or  unenforceable  in  any  respect,  the  validity  and  enforceability  of the
remaining  terms  and  provisions  of  this  Agreement  shall  not in any way be
affected or impaired  thereby and the parties will attempt to agree upon a valid
and enforceable provision that is a reasonable substitute therefor,  and upon so
agreeing, shall incorporate such substitute provision in this Agreement.


                                      -17-
<PAGE>

     5.12 Replacement of Securities. If any certificate or instrument evidencing
any Securities is mutilated,  lost, stolen or destroyed, the Company shall issue
or cause to be issued in exchange  and  substitution  for and upon  cancellation
thereof,  or  in  lieu  of  and  substitution  therefor,  a new  certificate  or
instrument,  but only upon receipt of evidence  reasonably  satisfactory  to the
Company  of such  loss,  theft  or  destruction  and  customary  and  reasonable
indemnity,  if requested.  The  applicants  for a new  certificate or instrument
under  such  circumstances  shall  also  pay any  reasonable  third-party  costs
associated with the issuance of such replacement Securities.

     5.13  Remedies.  In  addition  to being  entitled  to  exercise  all rights
provided herein or granted by law,  including  recovery of damages,  each of the
Purchasers  and the Company will be entitled to specific  performance  under the
Transaction  Documents.  The  parties  agree that  monetary  damages  may not be
adequate  compensation  for  any  loss  incurred  by  reason  of any  breach  of
obligations  described in the  foregoing  sentence and hereby agrees to waive in
any action for specific  performance  of any such  obligation the defense that a
remedy at law would be adequate.

     5.14 Payment Set Aside.  To the extent that the Company  makes a payment or
payments to any Purchaser  pursuant to any  Transaction  Document or a Purchaser
enforces or exercises its rights thereunder, and such payment or payments or the
proceeds of such  enforcement  or exercise or any part thereof are  subsequently
invalidated,  declared to be fraudulent or  preferential,  set aside,  recovered
from, disgorged by or are required to be refunded,  repaid or otherwise restored
to the  Company,  a  trustee,  receiver  or  any  other  person  under  any  law
(including, without limitation, any bankruptcy law, state or federal law, common
law or equitable  cause of action),  then to the extent of any such  restoration
the  obligation  or part thereof  originally  intended to be satisfied  shall be
revived and  continued  in full force and effect as if such payment had not been
made or such enforcement or setoff had not occurred.

     5.15  Independent  Nature  of  Purchasers'   Obligations  and  Rights.  The
obligations of each Purchaser under any Transaction Document are several and not
joint with the  obligations of any other  Purchaser,  and no Purchaser  shall be
responsible  in any way for the  performance  of the  obligations  of any  other
Purchaser under any Transaction  Document.  Nothing  contained  herein or in any
Transaction  Document,  and no action taken by any Purchaser  pursuant  thereto,
shall be deemed to constitute the Purchasers as a partnership, an association, a
joint  venture  or any other kind of entity,  or create a  presumption  that the
Purchasers  are in any way acting in concert or as a group with  respect to such
obligations or the transactions  contemplated by the Transaction Document.  Each
Purchaser  shall be  entitled to  independently  protect and enforce its rights,
including without limitation, the rights arising out of this Agreement or out of
the other  Transaction  Documents,  and it shall not be necessary  for any other
Purchaser  to be  joined  as an  additional  party  in any  proceeding  for such
purpose.  Each Purchaser has been  represented by its own separate legal counsel
in their review and negotiation of the Transaction Documents.

                            (Signature Page Follows)


                                      -18-
<PAGE>



     IN WITNESS WHEREOF, the parties hereto have caused this Securities Purchase
Agreement to be duly executed by their respective  authorized  signatories as of
the date first indicated above.


CYTOGEN CORPORATION                                 Address for Notice:
                                                    ------------------
                                                    650 College Road East
                                                    CN 5308
                                                    Suite 3100
By:/s/ Michael D. Becker                            Princeton, New Jersey 08540
   -----------------------------------
   Name: Michael D. Becker                          Attn:  Donald Novajosky
   Title: President and Chief Executive Officer     Tel:  609-750-8222
                                                    Fax:  609-452-2315




<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


STUART T. WEISBROD, IRA
-------------------------------                     Address for Notice:
Print Entity Name                                   ------------------
                                                    c/o Merlin BioMed Group
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Stuart T. Weisbrod                           Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Stuart T. Weisbrod                      Fax: 646-227-5201
Print Title:

Subscription Amount: $98,095
                      -------------------

Shares Purchased: 11,500
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


MERLIN BIOMED LONGTERM APPRECIATION FUND, L.P.
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Norman Schleifer                             Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Norman Schleifer                        Fax: 646-227-5201
Print Title: CFO

Subscription Amount: $127,950
                      -------------------

Shares Purchased: 15,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


STUART T. WEISBROD
-------------------------------                     Address for Notice:
Print Entity Name                                   ------------------
                                                    c/o Merlin BioMed Group
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Stuart T. Weisbrod                           Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Stuart T. Weisbrod                      Fax: 646-227-5201
Print Title:

Subscription Amount: $145,010
                      -------------------

Shares Purchased: 17,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


MERLIN BIOMED INT'L LIMITED
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Norman Schleifer                             Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Norman Schleifer                        Fax: 646-227-5201
Print Title: CFO

Subscription Amount: $330,290.13
                      -------------------

Shares Purchased: 38,721
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]



MERLIN BIOMED II, L.P.
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Norman Schleifer                             Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Norman Schleifer                        Fax: 646-227-5201
Print Title: CFO

Subscription Amount: $213,250
                      -------------------

Shares Purchased: 25,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


MERLIN BIOMED OFFSHORE MASTER FUND, L.P.
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Norman Schleifer                             Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Norman Schleifer                        Fax: 646-227-5201
Print Title: CFO

Subscription Amount: $980,950
                      -------------------

Shares Purchased: 115,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


MERLIN BIOMED, L.P.
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    230 Park Avenue, Suite 928
                                                    New York, NY  10169

By:/s/ Norman Schleifer                             Attn: Norman Schleifer
   --------------------------------------           Tel: 646-227-5200
Print Name: Norman Schleifer                        Fax: 646-227-5201
Print Title: CFO

Subscription Amount: $554,450
                      -------------------

Shares Purchased: 65,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE POST VENTURE III, LP
-----------------------------------------------     Address for Notice:
Print Entity Name                                   ------------------
                                                    OrbiMed Advisors LLC
                                                    767 Third Avenue, 30th Floor
                                                    New York, NY  10017

By:/s/ Sven H. Borho                                Attn: Andrew Kanarek
   --------------------------------------           Tel: 212-739-6406
Print Name: Sven H. Borho                           Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $301,962
                      -------------------

Shares Purchased: 35,400
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE INTEGRATED HOLDINGS IV POST VENTURE, LP
----------------------------------------------------  Address for Notice:
Print Entity Name                                     ------------------
                                                      OrbiMed Advisors LLC
                                                      767 Third Avenue
                                                      30th Floor
                                                      New York, NY  10017

By:/s/ Sven H. Borho                                  Attn: Andrew Kanarek
   --------------------------------------             Tel: 212-739-6406
Print Name: Sven H. Borho                             Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $307,080
                      -------------------

Shares Purchased: 36,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE NETHERLANDS II, L.P.
-----------------------------------                   Address for Notice:
Print Entity Name                                     ------------------
                                                      OrbiMed Advisors LLC
                                                      767 Third Avenue
                                                      30th Floor
                                                      New York, NY  10017

By:/s/ Sven H. Borho                                  Attn: Andrew Kanarek
   --------------------------------------             Tel: 212-739-6406
Print Name: Sven H. Borho                             Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $168,041
                      -------------------

Shares Purchased: 19,700
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE INTEGRATED HOLDINGS, V, LP
-----------------------------------------             Address for Notice:
Print Entity Name                                     ------------------
                                                      OrbiMed Advisors LLC
                                                      767 Third Avenue
                                                      30th Floor
                                                      New York, NY  10017

By:/s/ Sven H. Borho                                  Attn: Andrew Kanarek
   --------------------------------------             Tel: 212-739-6406
Print Name: Sven H. Borho                             Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $423,710.69
                      -------------------

Shares Purchased: 49,673
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE POST VENTURE IV L.P.
---------------------------------------               Address for Notice:
Print Entity Name                                     ------------------
                                                      OrbiMed Advisors LLC
                                                      767 Third Avenue
                                                      30th Floor
                                                      New York, NY  10017

By:/s/ Sven H. Borho                                  Attn: Andrew Kanarek
   --------------------------------------             Tel: 212-739-6406
Print Name: Sven H. Borho                             Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $519,477
                      -------------------

Shares Purchased: 60,900
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE VENTURE CAPITAL III LP
---------------------------------------           Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Sven H. Borho                              Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Sven H. Borho                         Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $20,472
                      -------------------

Shares Purchased: 2,400
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE VENTURE CAPITAL IV L.P.
---------------------------------------           Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Sven H. Borho                              Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Sven H. Borho                         Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $47,768
                      -------------------

Shares Purchased: 5,600
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE INTEGRATED HOLDINGS II LIMITED
-------------------------------------------       Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Sven H. Borho                              Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Sven H. Borho                         Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $321,581
                      -------------------

Shares Purchased: 37,700
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE NETHERLANDS III - LP
-------------------------------------------       Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Sven H. Borho                              Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Sven H. Borho                         Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $47,768
                      -------------------

Shares Purchased: 5,600
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


KNIGHTSBRIDGE NETHERLAND I LP
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Sven H. Borho                              Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Sven H. Borho                         Fax: 212-739-6444
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $188,513
                      -------------------

Shares Purchased: 22,100
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]



HFR SHC AGGRESSIVE FUND
-------------------------------------------       Address for Notice:
Print Entity Name                                 ------------------
                                                  OrbiMed Advisors LLC
                                                  767 Third Avenue, 30th Floor
                                                  New York, NY  10017

By:/s/ Dora Hines                                 Attn: Andrew Kanarek
   --------------------------------------         Tel: 212-739-6406
Print Name: Dora Hines                            Fax: 212-739-6444
Print Title: Dora Hines for & on behalf of
             HFR Asset Management, LLC as
             attorney in fact

Subscription Amount: $153,540
                      -------------------

Shares Purchased: 18,000
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


HIGHWAY PARTNERS, LP
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  Principled Capital Management
                                                  666 Fifth Avenue, 34th Fl.
                                                  NY, NY  10103

By:/s/ Gerald Catenacci                           Attn: Jessica Stern
   --------------------------------------         Tel: 212-484-5045
Print Name: Gerald Catenacci                      Fax: 212-484-5039
Print Title: Managing Member

Subscription Amount: $70,466.33
                      -------------------

Shares Purchased: 8,261
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]

THRUWAY PARTNERS, LP
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  Principled Capital Management
                                                  666 Fifth Avenue, 34th Fl.
                                                  NY, NY  10103

By:/s/ Gerald Catenacci                           Attn: Jessica Stern
   --------------------------------------         Tel: 212-484-5045
Print Name: Gerald Catenacci                      Fax: 212-484-5039
Print Title: Managing Member

Subscription Amount: $240,767.78
                      -------------------

Shares Purchased: 28,226
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


EXPRESSWAY PARTNERS, LTD
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  Principled Capital Management
                                                  666 Fifth Avenue, 34th Fl.
                                                  NY, NY  10103

By:/s/ Gerald Catenacci                           Attn: Jessica Stern
   --------------------------------------         Tel: 212-484-5045
Print Name: Gerald Catenacci                      Fax: 212-484-5039
Print Title: Managing Member

Subscription Amount: $438,757.61
                      -------------------

Shares Purchased: 51,437
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


DELTA OPPORTUNITY FUND, LTD.
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  950 3rd Avenue
Diaz & Altschul Advisors, LLC,                    16th Floor
As Investment Advisor                             New York, NY  10022

By:/s/ Christopher S. Mooney                      Attn: Chris Mooney
   --------------------------------------         Tel: 212-751-1011
Print Name: Christopher S. Mooney                 Fax: 212-751-5757
Print Title: Partner; OrbiMed Advisors LLC

Subscription Amount: $300,000.10
                      -------------------

Shares Purchased: 35,170
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


DELTA OPPORTUNITY FUND (INSTITUTIONAL), LLC
-------------------------------------------       Address for Notice:
Print Entity Name                                 ------------------
                                                  950 3rd Avenue
Diaz & Altschul Management, LLC,                  16th Floor
As Managing Member                                New York, NY  10022

By:/s/ Christopher S. Mooney                      Attn: Chris Mooney
   --------------------------------------         Tel: 212-751-1011
Print Name: Christopher S. Mooney                 Fax: 212-751-5757
Print Title: Chief Financial Officer

Subscription Amount: $199,994.38
                      -------------------

Shares Purchased: 23,446
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


THE TROUT GROUP LLC
-----------------------------                     Address for Notice:
Print Entity Name                                 ------------------
                                                  740 Broadway, Suite 903
                                                  New York, NY  10003

By:/s/ Jonathan Fassberg                          Attn: Jonathan Fassberg
   --------------------------------------         Tel: 212-477-9007
Print Name: Jonathan Fassberg                     Fax: 212-460-9028
Print Title: President

Subscription Amount: $50,113.75
                      -------------------

Shares Purchased: 1,172,346
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>

          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


DOMAIN PUBLIC EQUITY PARTNERS, L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------

by Domain Public Equity Associates, L.L.C.


By:/s/ Nicole Vitullo                             Attn: Nicole Vitullo
   --------------------------------------         Tel: 609-683-5656
Print Name: Nicole Vitullo                        Fax: 609-683-9789
Print Title: Managing Member

Subscription Amount: $999,997.49
                      -------------------

Shares Purchased: 117,233
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)


<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


CLSP, L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  230 Park Avenue, 20th Fl.
                                                  NY, NY  10169


By:/s/ Jeffrey Casdin                             Attn: Peter Freer
   --------------------------------------         Tel: 212-351-1970
Print Name: Jeffrey Casdin                        Fax: 212-351-1946
Print Title: GP

Subscription Amount: $327,688.48
                      -------------------

Shares Purchased: 38,416
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)

<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


CLSP II, L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  230 Park Avenue, 20th Fl.
                                                  NY, NY  10169


By:/s/ Jeffrey Casdin                             Attn: Peter Freer
   --------------------------------------         Tel: 212-351-1970
Print Name: Jeffrey Casdin                        Fax: 212-351-1946
Print Title: GP

Subscription Amount: $273,275.61
                      -------------------

Shares Purchased: 32,037
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>


          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


CLSP SBS - I, L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  230 Park Avenue, 20th Fl.
                                                  NY, NY  10169


By:/s/ Jeffrey Casdin                             Attn: Peter Freer
   --------------------------------------         Tel: 212-351-1970
Print Name: Jeffrey Casdin                        Fax: 212-351-1946
Print Title: GP

Subscription Amount: $122,243.43
                      -------------------

Shares Purchased: 14,331
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>



          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


CLSP SBS - II, L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  230 Park Avenue, 20th Fl.
                                                  NY, NY  10169


By:/s/ Jeffrey Casdin                             Attn: Peter Freer
   --------------------------------------         Tel: 212-351-1970
Print Name: Jeffrey Casdin                        Fax: 212-351-1946
Print Title: GP

Subscription Amount: $42,052.90
                      -------------------

Shares Purchased: 4,930
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)



<PAGE>



          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


CLSP OVERSEAS LTD.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  230 Park Avenue, 20th Fl.
                                                  NY, NY  10169


By:/s/ Jeffrey Casdin                             Attn: Peter Freer
   --------------------------------------         Tel: 212-351-1970
Print Name: Jeffrey Casdin                        Fax: 212-351-1946
Print Title: GP

Subscription Amount: $234.737.07
                      -------------------

Shares Purchased: 27,519
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)

<PAGE>



          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


MILLENCO L.P.
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  Millenco L.P.
                                                  666 Fifth Avenue, 8th Floor
                                                  New York, NY  10103

By:/s/ Robert Williams                            Attn: Terry Feeney
   --------------------------------------         Tel: 212-841-4100
Print Name: Robert Williams                       Fax: 212-841-4141
Print Title: CFO

Subscription Amount: $749,991.72
                      -------------------

Shares Purchased: 87,924
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)

                               c/o Merrill Lynch
                          Professional Clearing Corp.
                            222 Broadway, 6th Floor
                            New York, New York 10008
                                TIN: 13-3247006

<PAGE>



          [PURCHASER SIGNATURE PAGES TO SECURITIES PURCHASE AGREEMENT]


VERTICAL VENTURES INVESTMENTS, LLC
-----------------------------------               Address for Notice:
Print Entity Name                                 ------------------
                                                  641 Lexington Avenue, 26th Fl.
                                                  NY, NY  10022


By:/s/ Joshua Silverman                           Attn: Joshua Silverman
   --------------------------------------         Tel: 212-974-3070
Print Name: Joshua Silverman                      Fax: 212-207-3452
Print Title: Manager

Subscription Amount: $999,997.49
                      -------------------

Shares Purchased: 117,233
                  -----------------------

       SECURITY DELIVERY INSTRUCTIONS (IF DIFFERENT THAN NOTICE ADDRESS)