Document:

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                                                                   Exhibit 10.16
                                                                   -------------

                                   AMENDMENT

                                      TO

               ASSET CONTRIBUTION AND RECAPITALIZATION AGREEMENT

     This Amendment to Asset Contribution and Recapitalization Agreement (The
"Amendment") is made as of the 8th day of July, 1999 among Clark USA, Inc.,
Clark Refining & Marketing, Inc., OTG (Holdings), Inc. (formerly known as OTG,
Inc.) and CM acquisition, Inc.

                                    RECITALS

     A.  The parties hereto are parties to an Asset Contribution and
Recapitalization Agreement (the "Recapitalization Agreement").

     B.  The parties hereto desire to amend and modify certain provisions of the
Recapitalization Agreement as provided herein.

                                   AGREEMENT

     In consideration of the foregoing, the mutual covenants herein contained
and other good and valuable consideration (the receipt, adequacy and sufficiency
of which are hereby acknowledged by the parties by their execution hereof), the
parties agree as follows.

1.  Definitions.  For purposes of this Amendment, capitalized terms used herein
have the same meanings ascribed to them in the Recapitalization Agreement.

2.  Amendments to the Recapitalization Agreement.

     2.1.  Branded Jobber Accounts Receivable.  Notwithstanding Section 2.1(g)
of the Recapitalization Agreement, the term "Assets" does not include accounts
receivable from Jobbers. Assumed Liabilities do not include fuel payables or
excise tax payables related to Jobber sales. Final Closing Working Capital will
be computed without regard to such accounts receivable, fuel payables and excise
tax payables.

     2.2  Working Capital.  The last sentence of Section 2.5(c) of the
Recapitalization Agreement is hereby amended to read as follows:

          As used herein, "Estimated Working Capital Adjustment Amount" shall
          mean a positive or negative amount equal to the Estimated Working
          Capital minus negative $26,700,000 (such number, "Target Working
          Capital").

     2.3  Stub Equity Amount.  The definition of Stub Equity Amount is hereby
amended to read as follows: "'Stub Equity Amount' means $4,200,000."
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     2.4  Schedule 3.17.  Schedule 3.17 to the Recapitalization Agreement is
hereby amended by deleting the following identified Retail Stores from the
"Unknown" classification and adding them to the "Identified Contamination Sites"
classification in such Schedule: 614; 2097; 1171; 2101; 1426; 2102; 1822; 2104;
2040; 2173; 2052; 2178; 2055; 2179; and 2056. Schedule 3.17 to the
Recapitalization Agreement is hereby amended by deleting the following
identified Retail Stores from the "Remediated Site" classification to the
"Identified Contamination Sites" classification in such Schedule: 1043; 1209;
and 1786. Schedule 3.17 to the Recapitalization Agreement is hereby amended by
deleting the following identified Retail Stores from the "Unknown Sites"
classification and adding them to the "Remediated Site" classification in such
Schedule:  1643; and 1794.

     2.5  Capitalized Leases.  Section 2.5(e)(ii) of the Recapitalization
Agreement requires the Initial Note Amount to be reduced, as of the Closing
Date, by the amount of indebtedness under any Lease which is a capitalized
lease. The parties have agreed to estimate this amount as of the Closing Date to
be $500,000 and have agreed further that the actual amount will be determined in
the manner set forth in Section 2.8 of the Recapitalization Agreement.

     2.6.  Tax Bulk Sales Laws.  Under Section 10.12(b) of the Recapitalization
Agreement, Seller and Buyer are obligated, among other things, to take any and
all actions necessary for Seller and Buyer to comply with any bulk sales
provisions under Law relating to Taxes to eliminate all transferee liability to
Buyer. The parties have agreed that, instead of escrowing any amounts as
required by Law to eliminate transferee liability to BUYER, OTG, Inc. ("OTG")
may, subject to the qualifications set forth herein, offset any amounts owed to
Seller by OTG under the Supply Agreement for any amount that any Governmental
Authority seeks to collect from OTG as a result of the parties not escrowing
such amounts in accordance with applicable Law. In the event any Governmental
Authority makes such a written claim against OTG, OTG will promptly notify
Seller of such claim and allow Seller to assume defense of any such claim.
Seller may, at Seller's expense, defend such claim as Seller may determine in
Seller's discretion. Seller will pay any and all costs that OTG may incur in
connection with such claim. If Seller does not elect in writing to OTG to defend
such claim within 30 days from date of notice from the Governmental Authority to
OTG, OTG may offset the assessed amount from any and all payments due to Seller
under the Supply Agreement and remit such amount directly to the appropriate
Governmental Authority. If Seller does elect to defend such claim within such 30
day period and there is a final assessment against OTG and Seller does not pay
such final assessment within the notice period prescribed by the final
assessment or, if no period is so stated, within 10 days of such final
assessment, then OTG may offset the assessment amount from any and all payments
due to Seller under the Supply Agreement and remit such amount directly to the
appropriate Governmental Authority.

     2.7.  Laptop Computer Leases.  Within thirty (30) days of the Closing Date,
Seller and OTG shall jointly inventory all laptop computers described in Lease
Agreements dated November 30, 1995, between IFC/Sentry Financial and Seller
identified as Numbers 95-1114-005 and 95-1114-006 ("Laptop Computer Leases"). If
Seller and OTG agree based on such inventory that less than all of the laptop
computers in the Laptop Computer Leases were delivered by Seller to OTG as of
the Closing Date ("Missing Computers"), then Seller shall deliver to OTG
comparable laptop computers pursuant to the 4Laptop Computer Leases to replace
one-half of the Missing Computers ("Replacement Computers") provided that any
computers voluntarily given to OTG by Seller that were not required by Agreement
to be transferred to OTG shall be counted as Replacement Computers.

3.  No Other Modifications.  Nothing herein contained in any way impairs the
Recapitalization Agreement, or alters, waives, annuls, varies or affects any
provision, condition or covenant therein,

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except as specifically set forth in this Amendment. All other provisions of the
Recapitalization Agreement remain in full force and effect.

4.  Captions.  Captions contained in this Agreement have been inserted herein
only as a matter of convenience and in no way define, limit, extend or describe
the scope of this Amendment or the intent of any provision hereof.

5.  Counterparts.  This Amendment may be executed by the parties on any number
of separate counterparts, and all such counterparts so executed constitute one
agreement binding on all the parties notwithstanding that all the parties are
not signatories to the same counterpart.

6.  Successors and Assigns.  All provisions of this Amendment are binding upon,
inure to the benefit of and are enforceable by or against the parties and their
respective heirs, executors, administrators or other legal representatives and
permitted successors and assigns.

                                       CLARK USA, INC.

                                       By:  /s/  Dennis R. Eichholz
                                            -----------------------

                                       CLARK REFINING & MARKETING, INC.

                                       By:  /s/  Dennis R. Eichholz
                                            -----------------------

                                       OTG (HOLDINGS), INC.

                                       By:  /s/  Brandon Barnholt
                                            ---------------------
                                            Brandon Barnholt
                                            Chief Executive Officer/President

                                       CM ACQUISITION, INC.

                                       By:  /s/  Brandon Barnholt
                                            ---------------------
                                            Brandon Barnholt
                                            Chief Executive Officer/President

                                       3<PAGE>

                                                                   Exhibit 10.25

                             EMPLOYMENT AGREEMENT

                                BY AND BETWEEN
                              ENDOREX CORPORATION
                                      AND
                               STEVE KOULOGEORGE

     Agreement made this 19th day of September 2000, between ENDOREX
CORPORATION, a Delaware Corporation, (the "Company" or "Endorex") and Steve J.
Koulogeorge (the "Executive").

     The company is desirous of employing the Executive as CONTROLLER/ASSISTANT
TREASURER of the Company, and the Executive is desirous of becoming employed by
the Company in this capacity.

     The Company and the Executive desire to set forth in this Agreement the
terms and conditions on which the Executive will be employed by the Company as
its CONTROLLER/ASSISTANT TREASURER.

     Accordingly, in consideration of the promises and the respective covenants
and agreements of the parties herein contained, and intending to be legally
bound hereby, the parties hereto agree as follows:

1.  EMPLOYMENT

     The Company hereby agrees to employ the Executive, and the Executive hereby
agrees to serve the Company, on the terms and conditions set forth herein.

2.  TERM

     The employment of the Executive by the Company as provided in Section 1
will commence on September 25, 2000 and will end on September 24, 2004 unless
sooner terminated as provided in Section 8. If neither Executive or the Company
has provided written notice of termination not less than four (4) months prior
to September 24, 2004, this agreement shall continue for an additional year term
and shall continue to renew annually until either Executive or the Company has
provided written notice of termination at least four (4) months prior to the end
of any renewal term.

3.  POSITION AND DUTIES

     The Executive shall serve as CONTROLLER/ASSISTANT TREASURER of the Company
and its subsidiaries and shall have such responsibilities and authority
consistent with this position as may, from time to time, be assigned to the
Executive by the CEO or Board of Directors of the Company. The Executive shall
devote all his working time and efforts to the business affairs of the Company.
The Executive will report directly to the CEO of the Company or his or her
designee.

4.  COMPENSATION AND RELATED MATTERS

     (A)  SALARY.  During the period of the Executive's employment hereunder,
     the Company shall pay to the Executive a salary at a rate of not less than
     $98,000 per annum, payable in accordance with the Company's normal payroll
     and withholding practices.

     (B)  BONUSES.  At the end of each full year of employment, Executive shall
     be entitled to a targeted bonus of up to 15% of the Executive's annual base
     salary, as in effect at the time (it is understood that this represents a
     range of 0% to 15% of the Executive's annual base salary). Determination of
     any actual bonus shall be based upon the Executive's meeting reasonable
     written objectives and the overall performance of the Company for that
     period of time, as determined by the CEO and the Board of Directors in
     their sole discretion. The written objectives for the first year of this
     Agreement will be established during the first 45 days of employment and
     shall be subject to revision quarterly with the CEO based on information
     developed during the quarter.

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     (C)  EXPENSES.  The Company shall reimburse Executive for all normal, usual
     and necessary expenses incurred by Executive in furtherance of the business
     and affairs of the Company.

     (D)  OTHER BENEFITS.  The Executive shall be entitled to participate in or
     receive benefits under any employee benefit plan or arrangement made
     available by the Company as of this date and in the future to its
     employees, subject to and on a basis consistent with the terms, conditions
     and overall administration of such plans and arrangements. Nothing paid to
     the employee under any plan or arrangement presently in effect or made
     available in the future shall be deemed to be in lieu of the salary payable
     to the employee pursuant to paragraph (A) of this section.

     (E)  VACATIONS.  The Executive shall be entitled to three (3) weeks of paid
     vacation in each year of his employment (this will be prorated for any
     partial calendar years worked). The Executive shall also be entitled to all
     paid holidays given by the Company to its employees.

     (F)  OPTIONS AND GRANTS.  Subject to execution of this Agreement, Executive
     shall be granted as of the date of execution of this Agreement, an option
     (the "Stock Option") to purchase 15,000 shares of Endorex's Common Stock
     (the "Option Shares") at a price per share equal to the Closing Price of
     the Company's Common Stock on the date of execution of this Agreement
     [vesting and becoming exercisable as to 25% of the Option Shares on the
     first anniversary of the grant of the Stock Option and then an additional
     25% each yearly anniversary thereafter, as long as Executive is employed by
     Endorex on such vesting dates]. The Stock Option shall be granted under the
     terms of the Company's Amended and Restated 1995 Omnibus Incentive Plan
     (the "Plan") and the terms of the Company's standard Stock Option
     Agreement, which Executive must agree to and sign as a condition of
     receiving the Stock Option. The grant of the Stock Option shall not
     preclude the participation of the Executive in any other stock grant or
     option plan of the Company which the Board may grant from time to time.

5.  OFFICES

     The Executive agrees to serve without additional compensation, if elected
or appointed thereto, as an executive of Endorex or other Endorex subsidiaries
(collectively "Endorex"), presently existing and as may be established in the
future, and consistent with the position of the Executive with the Company at
the time of such appointment, provided that the Executive is indemnified for
serving in any and all such capacities on a basis no less favorable than
provided by the Company's by-laws and any applicable Directors and Officers
insurance in effect during the term hereof. Executive agrees that, upon
termination of his employment with the Company, for any reason whatsoever, he
will terminate from all positions as an employee of Endorex and all of its
subsidiaries.

6.  CONFIDENTIAL INFORMATION

     Executive covenants and agrees that he will not (except as required in the
course of his employment or as required by law), while in the employment of the
Company or at any time thereafter, communicate or divulge to, or use for his own
benefit, or for the benefit of any other person, firm, association or
corporation, without the consent of the Company, as applicable, any information
concerning any inventions, discoveries, improvements, processes, formulas,
apparatus, equipment, methods, trade secrets, research, secret data, cost or
uses or purchasers of the Company's current or future products (including but
not limited to: its cancer products, POH and ImmTher(R): its oral/mucosal
protein, peptide and vaccine delivery system; the Elan technologies in either of
the two joint ventures with this company, and its MDP vaccine adjuvant product),
research activities, or services, or other confidential information possessed,
owned, or used by the Company that may be communicated to, acquired by, or
learned of by the Executive in the course of, or as a result of, his employment
with the Company. All records, files, memoranda, reports, price lists, customer
lists, drawings, plans, sketches, documents, equipment and like, relating to the
business of the Company, which the Company uses or prepares or comes into
contact with, shall remain the sole property of the Company, as applicable. The
obligations of confidentiality shall not apply to such information that (a) is
at the time of receipt a matter of public knowledge or after its receipt becomes
public knowledge through no act or omission on the part of Executive, or (b) the
Executive can establish by reasonable proof was known to him prior to disclosure
by the Company. Executive acknowledges that any invention, improvement,
discovery, process, formula, method or other intellectual property
("inventions"), whether or not patentable or copyrightable developed by
Executive, alone or jointly with others, on working time or using material,
resources or facilities of the Company or which relate to Executive's work for
the Company or are based on the Company's confidential information is the
exclusive property of the Company. Executive assigns all of his right, title and
interest in and to any such inventions to the Company.

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7.  COMPETITION

     (A)  During the period of the Executive's employment by the Company and for
     a period of eighteen (18) months after such employment ends (the
     "Restricted Period") (whether such employment shall have ended by reason of
     the expiration or termination of this Agreement or otherwise), Executive
     will not (i) engage in; (ii) have any interest in any person, firm or
     corporation that engages in; or (iii) perform any services for any person,
     firm or corporation that engages in direct competition with the Company, or
     any of its subsidiaries in the development, research relating to,
     manufacture, processing, marketing, distribution, or sale of products that
     are substantially similar to products ("Products") that were researched,
     developed, licensed, manufactured, processed, distributed, or sold by the
     Company, or any of its subsidiaries, at any time during the twelve (12)
     month period immediately preceding the termination of his employment. The
     parties agree that the Company currently conducts business in the following
     areas: 1) immunomodulators for cancer and infectious disease and vaccine
     adjuvants based on muramyl dipeptide technology, 2) liposome-based
     particles for oral/mucosal vaccine and drug delivery, 3) PLGA microspheres
     for oral delivery of vaccines, 4) monoterpene-based compounds for the
     prevention and treatment of cancer, and 5) delivery of iron chelators using
     Elan Corporation's MEDIPAD(R) technology. For the avoidance of doubt, the
     parties agree that "Products" shall include any technology and/or products
     that the Company in-licenses during the term of Executive's employment
     hereunder.

     (B)  Executive will not, directly or indirectly, employ, solicit for
     employment, or advise or recommend to any other person that they employ or
     solicit for employment, any person employed by the Company during the
     period of the Executive's employment by the Company and for a period of
     eighteen (18) months thereafter.

     (C)  Notwithstanding any provision of this Section 7 to the contrary,
     Executive shall be permitted to own up to three percent (3%) of the total
     shares of all classes of publicly-traded stock of any corporation engaging
     in direct competition with the Company as described in section 7(A) above,
     as a passive investment.

8.  TERMINATION

     (A)  Notwithstanding any provision of this Agreement to the contrary,
     Executive's employment shall automatically terminate upon his death, and
     the Company at any time may terminate his employment immediately by giving
     him written notice of such termination (i) for cause, as hereinafter
     defined; (ii) if Executive shall materially violate any of the provisions
     of Section 6 or 7 hereof; or (iii) if Executive shall become physically or
     mentally incapacitated and by reason thereof be unable to perform his
     duties hereunder with or without reasonable accommodation for a period of
     ninety (90) consecutive days. For the purpose of clause (i) of this
     Subsection 8A, "for cause" shall mean any of the following events: (x)
     conviction in a court of law of any crime or offense involving money or
     other property of the Company, or any of its subsidiaries, or any felony,
     (y) violation of specific written directions of the CEO or Board of
     Directors of the Company regarding lawful activities consistent with the
     Executive's job responsibilities to improve the business of the Company,
     provided, however, no discharge shall be deemed "for cause" under this
     clause (y) unless Executive shall have first received written notice from
     the CEO of the Company advising of the acts or omissions that constitute
     such violation, and such violation continues uncured for a period of (30)
     days after Executive shall have received such notice, or (z) intentional,
     reckless or grossly negligent conduct by Executive constituting misconduct.
     The Company may also terminate Executive's employment at any time without
     cause, subject to its obligations under Section 8C below.

     (B)  Executive may terminate his employment with the Company upon thirty
     (30) days' written notice. If Executive terminates his Employment with the
     Company pursuant to this Section 8B, Executive shall only be entitled to
     any unpaid compensation accrued through the last day of Executive's
     employment; provided, however, that Executive may terminate his employment
     agreement with the Company for "Good Reason" and within four (4) months
     after a "Change in Control" and be entitled to the benefits stated in sub-
     paragraph C hereafter.

     (C)  In the event that (i) the Company terminates the employment of
     Executive for any reason (other than "for cause" as defined or as a
     consequence of Executive's violation of clause (ii) of Subsection 8A

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     above [or due to disability or death]), or (ii) Executive terminates his
     employment for Good Reason within four (4) months after a Change in
     Control, then Executive shall be paid his then current salary plus any
     earned but unpaid bonus, prorated for the amount of the calendar year
     worked, for a period of four (4) months following termination, subject to
     set off for amounts earned from alternative employment. A termination by
     Executive for "Good Reason" shall mean a termination by Executive within
     thirty (30) days of (i) a material reduction in Executive's level of
     responsibility, (ii) a reduction in his level of base salary or (iii) a
     relocation of Executive's primary worksite without his consent of more than
     50 miles from Lake Forest, IL. Executive shall give the Company thirty (30)
     days' written notice and opportunity to cure prior to any termination for
     Good Reason. "Change in Control" shall have the same meaning as in the
     Company's Amended and Restated 1995 Omnibus Incentive Plan.

9.   SUCCESSORS: BINDING AGREEMENT

     (A)  The Company will require any successor (whether direct or indirect, by
     purchase, merger, consolidation or otherwise) to all or substantially all
     of the business and/or assets of the Company to assume this Agreement in
     the same manner and to the same extent that the Company would be required
     to perform if no such succession had taken place. As used in this
     Agreement, "Company" shall mean the Company as hereinbefore defined and any
     successor to its business and/or assets as aforesaid which executes and
     delivers the agreement provided for in this Section 9, or which otherwise
     becomes bound by all the terms and provisions of this Agreement by
     operation of law. If the successor does not agree to be bound by this
     agreement, and Executive is terminated, the Company will pay Executive
     severance pay as set forth in Section 8(C).

     (B)  If the Executive should die during the term of this Agreement, any
     amounts earned hereunder but not yet paid, unless otherwise provided
     herein, shall be paid in accordance with the terms of this Agreement to the
     Executive's devisee, legatee, or other designee or, if there be no such
     designee, to the Executive's estate. The Executive shall not be entitled to
     assign any of his rights or obligations under this Agreement.

10.  NOTICE

For all purposes of this Agreement, notices, demands and all other
communications provided for in this Agreement shall be in writing and shall be
deemed to be effective upon personal delivery or fax or two (2) days after
deposit in the U.S. registered mail, return receipt requested, postage prepaid,
addressed as follows:

     If to the Executive:        If to the Employer:
          4019 Crestwood Drive        28101 N. Ballard Drive, Suite F
          Northbrook, IL  60062        Lake Forest, Ill. 60045

Or to such other address as any party may have furnished to the others in
writing in accordance herewith, except that notices of change of address shall
be effective only upon receipt.

11.  MISCELLANEOUS

No provisions of this Agreement may be modified, waived or discharged unless
such waiver, modification or discharge is agreed to in writing signed by the
parties hereto. No waiver by either party hereto at any time of any breach by
the other party hereto of, or in compliance with, any condition or provision of
this Agreement to be performed by such other party shall be deemed a waiver of
similar or dissimilar provisions or conditions at the same or at any prior or
subsequent time. No agreements or representations, oral or otherwise, express or
implied, with respect to the subject matter hereof have been made by either
party which are not set forth expressly in this Agreement. The validity,
interpretation, construction and performance of this Agreement shall be governed
by the laws of the State of Illinois.

12.  VALIDITY

The invalidity or unenforceablitity of any provision or provisions of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement, which shall remain in full force and effect.

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13.  COUNTERPARTS

This agreement may be executed in one or more counterparts, each of which shall
be deemed to be an original, but all of which together will constitute one and
the same instrument.

15.  ARBITRATION

Any dispute or controversy arising under or in connection with this Agreement,
other than Sections 6 or 7, shall be settled exclusively by arbitration,
conducted before a panel of three arbitrators, in Chicago, Illinois, in
accordance with the rules of the American Arbitration Association then in
effect. Judgment may be entered on the arbitrator's award in any court having
jurisdiction. The arbitration fees shall be borne by the Company but each party
shall be responsible for its own legal fees. The parties agree that any dispute
arising out of or relating to Sections 6 or 7 shall be resolved in the State
and/or Federal courts located in Lake County, Illinois and the parties consent
to the jurisdiction of such courts.

IN WITNESS WHEREOF, the parties have executed this Agreement on the date and
year first above written.

                                Endorex Corporation

/s/ Sarah Bauer             By: /s/ Michael S. Rosen
------------------------        -------------------------
      Attest                    Michael S. Rosen
                                President/CEO

                                /s/ Steve J. Koulogeorge
                                -------------------------
                                Steve J. Koulogeorge

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