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                                                                   Exhibit 10.19

                              CONSULTING AGREEMENT


This Agreement is made and entered into as of December 15, 1998 by and between
Alteon Inc., a Delaware corporation whose principal address is 170 Williams
Drive, Ramsey, New Jersey 07446 (the "Company"), and Mark Novitch, M.D., an
individual whose address is 3558 Albermarle Street NW, Washington, D.C. 20008
("Chairman").


Whereas, the Company desires to retain Chairman as an independent contractor to
act as Chairman of Alteon's Board of Directors starting on December 15, 1998
until the annual meeting in 2000 and until a successor is elected and qualified
and Chairman is willing to perform such consulting services, all on the basis
set forth more fully herein;



NOW, THEREFORE, the parties agree as follows:


1.       SERVICES. Chairman agrees to serve as Chairman of the Company's Board
         of Directors and to carry out assignments for the Company as requested
         by the Board from time to time or as authorized by the Company's
         By-laws. In addition to chairing meetings of the Board, it is expected
         that the Chairman shall dedicate approximately one day per week (as and
         when appropriate) to the affairs of the Company. Chairman agrees to
         perform the Services hereunder faithfully, diligently, and to the best
         of Chairman's skill and ability.


2.       CONSULTING FEE. (a) In consideration of the performance of the services
         called for by this Agreement, the Company agrees to pay Chairman as
         compensation a retainer of $60,000 per year. To the extent the Chairman
         is called upon to dedicate materially more time to the affairs of the
         Company than contemplated by Section 1 of this Agreement, the Company
         and the Chairman may agree to fix additional compensation therefor. In
         addition, the Company will issue and deliver stock options to purchase
         200,000 shares of the Company's common stock at an exercise price of
         $.875, the fair market value of Alteon stock on December 15, 1998, when
         the Compensation Committee and the Board approved this award. The
         options will be subject to the terms and conditions of the Company's
         Amended 1995 Stock Option Plan and the Company's Standard Non-Qualified
         Stock Option Grant Agreement. The options will vest monthly over a two
         year period. The Board or the Compensation Committee in the exercise of
         its discretion may elect to accelerate this vesting schedule as a
         reward for performance. In addition, out of pocket expenses and routine
         items covered by normal business expense accounts will be covered when
         traveling and working on behalf of Alteon. The Chairman will submit a
         list of such expenses. The Company shall therefore promptly make full
         payment to Chairman in cash of the amount due for the expenses.


         (b) The Non-Qualified Stock Option Grant Agreement for the options
         provided for in the preceding paragraph contain provisions to the
         following effect:

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                                                                   Exhibit 10.19

                           (1) The options shall be transferable to the extent
         afforded in the Company's 1995 Stock Option Plan and as may be
         permissible under the applicable registration statement filed by the
         Company under the Securities Act of 1933. The Company represents that
         it has available or shall cause to be available sufficient shares under
         the Plan to cover stock to be issued pursuant to such Plan upon the
         Chairman's exercise of the options.

                           (2) All unvested options will become exercisable
         immediately upon a merger, consolidation, acquisition of property or
         stock, reorganization (other than a mere reincorporation or the
         creation of a holding company) or liquidation of the Company, as a
         result of which the shareholders of the Company receive cash, stock or
         other property in exchange for or in connection with their shares of
         the Company's Common Stock. In addition, such options shall vest and
         become exercisable immediately in the event of a change in control of
         the Company. A change in control of the Company shall be deemed to
         occur if (a) the Company is merged with or into or consolidated with
         another corporation or other entity under circumstances where the
         shareholders of the Company immediately prior to such merger or
         consolidation do not own after such merger or consolidation shares
         representing at least fifty percent of the voting power of the Company
         or the surviving or resulting corporation or other entity, as the case
         may be, or (b) if the Company is liquidated or sells or otherwise
         disposes of substantially all of its assets to another corporation or
         entity, or (c) if any person (as such term is used in Sections 13(d)
         and 14(d)(2) of the Securities Exchange Act of 1934) shall become the
         beneficial owner (within the meaning of Rule 13d-3 under such Act) of
         forty percent (40%) or more of the Common Stock other than pursuant to
         a plan or arrangement entered into by such person and the Company or
         otherwise approved by the Board of Directors, or (d) during any period
         of two (2) consecutive years, individuals who at the beginning of such
         period constitute the entire Board of Directors shall cease for any
         reason to constitute a majority of the Board unless the election or
         nomination for election by the Company's shareholders of each new
         director was approved by a vote of at least two-thirds of the directors
         then still in office who were directors at the beginning of the period.

                           (3) In the event that the accelerated vesting caused
         by Section 4(c)(2) of this Agreement (i) constitutes a "parachute
         payment" within the meaning of Section 280G of the Internal Revenue
         Code, and (ii) but for this Section 4(c)(3), would be subject to the
         excise tax imposed by Section 4999 of the Code (the "Excise Tax"), then
         the portion of the option which would have become immediately vested
         and exercisable under Section 4(c)(2) may be reduced to the portion
         which the Chairman, in his sole discretion, determines would result in
         no portion, or a lesser portion, of the option being subject to the
         Excise Tax. The determination by the Chairman of any reduction shall be
         conclusive and binding upon the Company. The Company shall reduce the
         portion of the option

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                                                                   Exhibit 10.19

         which is vested and exercisable only upon written notice by the
         Chairman indicating the amount of such reduction.

3.       EMPLOYMENT TAXES AND BENEFITS. Chairman acknowledges and agrees that it
         shall be Chairman's sole obligation to report as self-employment income
         all compensation received by Chairman pursuant to this Agreement.
         Because Chairman is an independent contractor, Chairman understands
         that the Company is not obligated to pay any withholding taxes, social
         security, unemployment or disability insurance or similar items in
         connection with any payments made to Chairman by the Company pursuant
         to this Agreement. Chairman shall not be entitled to participate in any
         plans, arrangements, or distributions by the Company pertaining to any
         bonus, stock option, profit-sharing, insurance (except as provided in
         Section 9 of this Agreement) or similar benefits for Company employees.


4.       PRE-EXISTING OBLIGATIONS. Chairman represents and warrants that
         Services performed pursuant to this Agreement will not conflict with
         any other existing obligation of Chairman to any third party. Chairman
         will promptly inform the Company in advance of any potential conflicts
         of interest that may arise due to Chairman's performance of services
         for any third party and Chairman agrees not to provide services
         requested by the Company if doing so would conflict with obligations of
         Chairman to third parties that arose prior to the Company's request for
         such services.


5.       INVENTION ASSIGNMENT, CONFIDENTIAL INFORMATION AND NON-COMPETITION
         AGREEMENT. In conjunction with this Consulting Agreement the Chairman
         shall agree to the terms and conditions of the Confidential Disclosure
         and Non-Use Agreement attached hereto as Exhibit A.


6.       TERM. This Agreement shall continue in effect for a period of up to two
         (2) years, subject to earlier termination as provided in Section 7.


7.       TERMINATION. This Agreement may be terminated as follows: (a) upon
         thirty (30) days written notice; (b) either party may terminate this
         Agreement in the event of a breach by the other party of any of the
         covenants contained herein if such breach continues uncured for a
         period of ten (10) days after written notice of such breach has been
         given to the breaching party, or (c) this Agreement will terminate
         automatically if Chairman ceases to serve as Chairman of the Board of
         Directors of the Company for any reason, including but not limited to,
         resignation, removal from office or failure to be re-elected by the
         Board.


8.       EFFECT OF TERMINATION. (a) Upon the termination of this Agreement, each
         party shall be released from all obligations and liabilities to the
         other occurring or arising after the date of such termination, except
         that any termination of this Agreement shall not relieve the Company of
         its obligations under Section 2 hereof to pay Chairman the consulting
         fee for services performed prior to termination and shall not relieve
         Chairman of Chairman's obligations under Sections 3, 4 and 5 hereof,
         nor shall any such termination relieve Chairman or the Company from any
         liability arising from any breach of this Agreement. Upon any such
         termination, Chairman shall promptly notify

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                                                                   Exhibit 10.19

         the Company of all Confidential Information and Designs and Materials
         in Chairman's possession and, at the expense of the Company and in
         accordance with the Company's Instructions, shall deliver to the
         Company all such Confidential Information and Designs and Materials.


         (b)  In the event of termination of this Agreement by the Company
              pursuant to clause 7(a) hereof, all unvested options shall become
              exercisable on the effective date of termination., and the Company
              shall pay the Chairman an amount equal to six (6) months'
              severance.

9.       INDEMNIFICATION. In the event the Chairman is or becomes a party or is
         threatened to be made a party to or is involved in any action, suit or
         proceeding, whether civil, criminal, administrative or investigative,
         by reason of the fact that he is or was a director, Chairman or any
         other officer of the Company, the Company shall indemnify and hold him
         harmless to the fullest extent legally permissible under and pursuant
         to any procedure specified in the General Corporation Law of the State
         of Delaware, as amended from time to time, against all expenses,
         liabilities and losses (including attorneys' fees, judgments, fines and
         amounts paid or to be paid in settlement) incurred or suffered by him
         in connection therewith. The Company will use its best efforts to
         obtain insurance to provide the indemnification required by this
         Section 10, provided that this Agreement shall not require the Company
         to obtain insurance on other than reasonable commercial terms.


10.      NOTICES. Any notices required or permitted hereunder shall be in
         writing and shall be deemed to have been given when delivered or
         certified mail, postage prepaid, to the address of the receiving party
         set forth in this Agreement, or to any other address of the receiving
         party designated by written notice in accordance with this Section.


11.      GOVERNING LAW. This Agreement shall be governed by and construed in
         accordance with the laws of the State of New Jersey, without regard to
         its choice of law principles.


12.      COMPLETE UNDERSTANDING; MODIFICATION. This Agreement constitutes the
         entire agreement of the parties and no waiver, modification or
         amendment of any provision hereof shall be effective unless in writing
         and signed by the parties hereto.



IN WITNESS WHEREOF, the parties hereto have executed this Agreement which is
effective as of the date first written above.


Alteon Inc.


By:  /s/Elizabeth O'Dell                    By:  /s/Mark Novitch
   ---------------------------------           --------------------------------
   Elizabeth O'Dell                            Mark Novitch, M.D.
   VP Finance & Administration


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                                                                   Exhibit 10.19



                                January 17, 2001


Mark Novitch, M.D.
3558 Albemarle Street NW
Washington, D.C. 20008

Dear Mark:

         This letter will set forth our agreement regarding the amendment of the
Consulting Agreement (the "Agreement") dated as of December 15, 1998 between you
and Alteon Inc. (the "Company").

         Section 6 of the Agreement is hereby amended to provide in its entirety
as follows:

         "6. TERM. This Agreement shall continue in effect until June 30, 2001,
subject to earlier termination as provided in Section 7."

In consideration of the performance of the services called for by the Agreement
as amended, in addition to the compensation provided therein, the Company will
issue and deliver to you stock options to purchase 50,000 shares of the
Company's common stock at an exercise price of $7.00, the fair market value of
the Company's stock on November 8, 2000 when the Company's Board of Directors
approved this award. The options will vest monthly over the period December 15,
2000 through the end of the term of the Agreement, as amended. Such stock
options will be subject to the terms and conditions set forth in Section 2 of
the Agreement (other than the terms and conditions relating to the number of
shares and the exercise price which terms and conditions are superseded by this
paragraph).

         If the foregoing is acceptable to you, please indicate your agreement
by signing and returning the enclosed copy of this letter.


                                       Sincerely,



KIM/law
Enclosure

Accepted and Agreed:


/s/ Mark Novitch                    Dated:  January 18, 2001
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Mark Novitch, M.D.