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                                                                    Exhibit 10.1

                              EMPLOYMENT AGREEMENT


     THIS EMPLOYMENT AGREEMENT (this "Agreement"), dated as of June 2, 1999, by
and between Alteon Inc., a Delaware corporation (the "Company"), and F. Kenneth
Andrews (the "Employee").

     WHEREAS, the Company wishes to employ the Employee as Senior Vice President
for Operations of the Company; and

     WHEREAS, the Employee wishes to enter into the employ of the Company as its
Senior Vice President for Operations;

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein, the parties hereby agree as follows;

1.   Term of Employment. Subject to the terms and conditions hereof, the Company
     will employ the Employee, and the Employee will serve the Company, as
     Senior Vice President for Operations for a period beginning on the date
     hereof and terminating three (3) years from such date, subject to extension
     by mutual agreement of the Company and the Employee (such term, as it may
     be extended, is hereinafter referred to as the "Term of Employment").

2.   Duties. During the Term of Employment, the Employee will serve as Senior
     Vice President for Operations, subject to the terms of this Agreement and
     the direction and control of the Board of Directors and/or the Chief
     Executive Officer of the Company. The Employee will, during the Term of
     Employment, serve the Company faithfully, diligently and competently and to
     the best of his ability, and will, consistent with the dignity of Senior
     Vice President for Operations of the Company, hold, in addition to the
     offices of Senior Vice President of Operations of the Company, such other
     offices in the Company to which he may be appointed or assigned from time
     to time by the Board of Directors and/or the Chief Executive Officer of the
     Company and will discharge such duties in connection therewith. The
     Employee shall devote all of his business time to the performance of his
     duties hereunder.

3.   Compensation. The Company will, during the Term of Employment, pay to the
     Employee as compensation for the performance of his duties and obligations
     hereunder an initial base salary at the rate of $190,000 per annum
     ("Salary"), payable in equal semi-monthly installments. Such Salary shall
     be reviewed annually by the Board of Directors of the Company in accordance
     with the Company's compensation program. In each of the

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EMPLOYMENT AGREEMENT                                                     PAGE 2

     Company's fiscal years during the Term of Employment, the Employee shall be
     eligible to receive a bonus, to be awarded at the sole discretion of the
     Board of Directors of the Company, in an amount of up to $15,000 for 1999
     and $30,000 for 2000 and subsequent years. The Board shall use as a basis
     for determining the extent of such bonus awards the attainment of stated
     goals and objectives for the Employee to be set by the Compensation
     Committee of the Board after consultation with the Chief Executive Officer.

4.   Other Benefits. During the Term of Employment:

     A.   The Company shall grant to the Employee an incentive stock option,
          pursuant to the Company's 1995 Stock Option Plan, to purchase 200,000
          shares of Common Stock of the Company ("Common Stock") with an
          exercise price equal to the closing price of the Company's Common
          Stock on June 2, 1999. Such option shall be in the form of and on such
          terms and conditions as provided in, the Company's standard form of
          Stock Option Grant Agreement in effect as of the date of this
          Agreement. Such option grant shall provide, on condition that the
          Employee is employed by the Company on the relevant vesting dates,
          that such options shall vest as follows:

          (1)  25,000 shares shall vest on the first anniversary of the date of
               this Agreement and 75,000 shares shall vest over a thirty-six
               month period at the rate of 3,125 shares on the first day of each
               calendar month commencing on June 1, 2000; and

          (2)  100,000 shares shall vest upon the accomplishment by the Employee
               of specified milestones, as determined by the Compensation
               Committee of the Board after consultation with the Chief
               Executive Officer; and

     B.   The Employee shall be entitled during the Term of Employment to
          participate in employee benefit plans and programs of the Company to
          the extent that his position, tenure, salary, age, health and other
          qualifications make him eligible to participate. The Company does not
          guarantee the adoption or continuance of any particular employee
          benefit plan or program during the Term of Employment, and the
          Employee's participation in any such plan or program shall be subject
          to the provisions, rules, regulations and laws applicable thereto;
          provided, however, that during the Term of Employment the Employee
          shall be entitled to health and hospital insurance benefits consistent
          with the past practices of the Company in effect with respect to
          Company personnel generally.

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EMPLOYMENT AGREEMENT                                                    PAGE 3

     C.   The Employee shall be entitled to three (3) weeks' vacation per year
          while employed hereunder. Such vacation may be taken by the Employee
          at such times as do not unreasonably interfere with the business of
          the Company. The accumulation of annual vacation time earned but not
          taken will be in accordance with the Company policy guidelines.
          Additional vacation will be earned in accordance with Company policy.

5.   Expenses. During the Term of Employment, the Company will reimburse the
     Employee for commuting and housing expenses in an amount not to exceed
     $30,000 per year, subject to the submission of appropriate vouchers and
     receipts. In addition, during the Term of Employment, all travel and other
     reasonable business expenses incident to the rendering of services by the
     Employee under this Agreement will be paid or reimbursed by the Company
     subject to the submission of appropriate vouchers and receipts in
     accordance with the Company's policy from time to time in effect.

6.   Death or Disability.

     A.   This Agreement shall be terminated by the death of the Employee. In
          addition, this Agreement may be terminated by the Board of Directors
          of the Company if the Employee shall be rendered incapable by illness
          or any other disability from complying with the terms, conditions and
          provisions on his part to be kept, observed and performed for a period
          in excess of 180 days (whether or not consecutive) or 90 days
          consecutively, as the case may be, during a 12-month period during the
          Term of Employment ("Disability"). If this Agreement is terminated by
          reason of Disability of the Employee, the Company shall give written
          notice to that effect to the Employee in the manner provided herein.
          In the event that the Employee receives disability insurance benefits
          paid for by the Company during any period prior to termination of this
          Agreement pursuant to this Section 6(a), the Employee's Salary shall
          be reduced by an amount equal to such disability insurance benefits
          during such period.

     B.   In addition to and not in substitution for any other benefits which
          may be payable by the Company in respect of the death or Disability of
          the Employee, in the event of such death or Disability, the Salary
          payable hereunder shall continue to be paid at the then current rate
          for three (3) months after the termination of employment, and any
          bonus to which the Employee would have been entitled for the year in
          which his death occurs shall be pro rated to the date of his death and
          paid not later than three (3) months after the termination of
          employment. In the event of the death of the Employee during the Term
          of this Agreement, the sums payable hereunder shall be paid to his
          personal representative.

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EMPLOYMENT AGREEMENT                                                    PAGE 4

7.   Disclosure of Information, Inventions and Discoveries. The Employee shall
     promptly disclose to the Company all processes, trademarks, inventions,
     improvements discoveries and other information related to the business of
     the Company (collectively, "Developments") conceived, developed or acquired
     by him alone or with others during the Term of Employment or during any
     earlier period of employment by the Company or any predecessor of the
     Company, whether or not during regular working hours or through the use of
     materials or facilities of the Company. All such Developments shall be the
     sole and exclusive property of the Company, and, upon request, the Employee
     shall promptly deliver to the Company all drawings, sketches, models and
     other data and records relating to such Developments. In the event any such
     Development shall be deemed by the Company to be patentable, the Employee
     shall, at the expense of the Company, assist the Company in obtaining a
     patent or patents thereon and execute all documents and do all such other
     acts and things necessary or proper to obtain letters of patents and to
     invest in the Company full right, title and interest in and to such
     Developments.

8.   Non-Disclosure. The Employee shall not, at any time during or after the
     Term of Employment, divulge, furnish or make accessible to anyone
     (otherwise than in the regular course of business of the Company) or use
     for his own account or for the account of any person any knowledge or
     information with respect to confidential or secret processes, inventions,
     discoveries, improvements, formulae, plans, materials, devices or ideas or
     other know-how, whether patentable or not, with respect to any confidential
     or secret development or research work or with respect to any other
     confidential or secret aspects of the Company's business (including,
     without limitation, customer lists, supplier lists and pricing arrangements
     with customers or suppliers).

9.   Non-Competition. The Company and the Employee agree that the services
     rendered by the Employee hereunder are unique and irreplaceable. The
     Employee hereby agrees that, during the Term of Employment and for a period
     of one (1) year thereafter, the Employee shall not (i) in any geographical
     area in the United States or in those foreign countries where the Company,
     during the Term of Employment, conducts or proposes to conduct business or
     initiates activities, engage or participate in, directly or indirectly
     (whether as an officer, director, employee, partner, consultant, holder of
     an equity or debt investment, lender or in any other manner or capacity),
     or lend his name (or any part or variant thereof) to any business which is,
     or as a result of the Employee's engagement or participation would become,
     competitive with any aspect of the business of the Company, such business
     being the commercialization of the measurement, prevention therapy or
     reversal of glucose-mediated non-enzymatic cross-linking of
     macro-

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EMPLOYMENT AGREEMENT                                                    PAGE 5

     molecules, and such other specific technologies in which the Company
     has, during the Term of Employment, initiated significant plans to develop
     products, (ii) deal, directly or indirectly, in a competitive manner with
     any customers doing business with the Company during the Term of Employment
     (except in connection with the performance of the duties and obligations of
     the Employee during the Term of Employment), (iii) solicit any officer,
     director, employee, consultant or agent of the Company to become an
     officer, director, employee, consultant or agent of the Employee, his
     respective affiliates or anyone else, and (iv) engage in or participate in,
     directly or indirectly, any business conducted under any name that shall be
     the same as or similar to the name of the Company or any trade name used by
     it. Ownership, in the aggregate, of less than 1% of the outstanding shares
     of capital stock of any corporation with one or more classes of its capital
     stock listed on a national securities exchange or publicly traded in the
     over-the-counter market shall not constitute a violation of the foregoing
     provision.

10.  Remedies. The Employee acknowledges that irreparable damage would result to
     the Company if the provisions of Section 7, 8, 9 or 14 were not
     specifically enforced, and agrees that the Company shall be entitled to any
     appropriate legal, equitable or other remedy, including injunctive relief,
     in respect to any failure to comply with the provisions of Section 7, 8, 9
     or 14.

11.  Termination for Cause. In addition to any other remedy available to the
     Company, either at law or in equity, the Employee's employment with the
     Company may be terminated by the Board of Directors for cause, which shall
     include (i) the Employee's conviction for, or plea of nolo contendere to, a
     felony or a crime involving moral turpitude, (ii) the Employee's commission
     of an act of personal dishonesty or a breach of fiduciary duty involving
     personal profit in connection with the Employee's employment by the
     Company, (iii) the Employee's commission of an act which the Board of
     Directors shall reasonably have found to have involved willful misconduct
     or gross negligence on the part of the Employee, in the conduct of his
     duties under this Agreement, (iv) habitual absenteeism, (v) the Employee's
     material breach of any material provision of this Agreement, or (vii) the
     willful and continued failure by the Employee to perform substantially his
     duties with the Company (other than any such failure resulting from his
     incapacity due to physical or mental illness). In the event of termination
     under this Section 11, the Company's obligations under this Agreement shall
     cease and the Employee shall forfeit all rights to receive any future
     compensation under this Agreement. Notwithstanding any termination of this
     Agreement pursuant to this Section 11, the Employee, in consideration of
     his employment hereunder to the date of such termination, shall remain
     bound by the provisions of Section 7, 8, 9 and 14 hereof.

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EMPLOYMENT AGREEMENT                                                    PAGE 6

12.  Termination Without Cause. Each of the Company and Employee may terminate
     this Agreement at any time for any reasons whatsoever, without any further
     liability or obligation of the Company to the Employee or of the Employee
     to the Company from and after the date of such termination (other than
     liabilities or obligations accrued but unsatisfied on, or surviving, the
     date of such termination), by sending thirty (30) days prior written notice
     to the other party. In the event (a) the Company elects to terminate this
     Agreement prior to the end of the Term of Employment or (b) the Company
     gives Employee notice of its election not to extend the Term of Employment
     beyond the expiration of the then current Term of Employment, or (c) by the
     date which is four (4) months prior to the end of the then current Term of
     Employment, the Company has not offered to extend the then current Term of
     Employment, the Company shall continue to pay the Employee the full Salary
     (exclusive of bonuses, if any) as such Salary would have otherwise accrued
     for a period of three (3) months if the effective date of such termination
     occurs prior to the first anniversary of this Agreement and for a period of
     six (6) months if the effective date of such termination occurs thereafter.
     In the event the Employee elects to terminate prior to the end of the Term
     of Employment, the Company's obligation to pay Salary shall cease as of the
     effective date of termination. Notwithstanding any termination of this
     Agreement pursuant to this Section 12, the Employee, in consideration of
     his employment hereunder to the date of such termination, shall remain
     bound by the provisions of Section 7, 8, 9 and 14 hereof. Any termination
     of this Agreement by the Company as provided in this Section 12 shall be in
     addition to, and not in substitution for, any rights with respect to
     termination of the Employee which the Company may have pursuant to Section
     11.

13.  Resignation. In the event that the Employee's services under this Agreement
     are terminated under any of the provisions of this Agreement (except by
     death), the Employee agrees that he will deliver his written resignation
     from all positions held with the Company to the Board of Directors, such
     resignation to become effective immediately; provided, however, that
     nothing herein shall be deemed to affect the provisions of Section 7, 8, 9
     and 14 hereof relating to the survival thereof following termination of the
     Employee's services hereunder, and provided, further, that except as
     expressly provided in this Agreement, the Employee shall be entitled to no
     further compensation hereunder.

14.  Data. Upon termination of the Term of Employment or termination pursuant to
     Sections 6, 11 or 12 hereof, the Employee or his personal representative
     shall promptly deliver to the Company all books, memoranda, plans, records
     and written data of every kind relating to the business and affairs of the
     Company which are then in his possession.

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EMPLOYMENT AGREEMENT                                                    PAGE 7

15.  Insurance. The Company shall have the right, at its own cost and expense to
     apply for and to secure in its own name, or otherwise, life, health or
     accident insurance or any or all of them covering the Employee, and the
     Employee agrees to submit to usual and customary medical examinations and
     otherwise to cooperate with the Company in connection with the procurement
     of any such insurance, and any claims thereunder.

16.  Waiver of Breach. Any waiver of any breach of this Agreement shall not be
     construed to be a continuing waiver or consent to any subsequent breach on
     the part either of the Employee or of the Company.

17.  Assignment. This Agreement shall inure to the benefit of and be binding
     upon the successors and assigns of the Company upon any sale of all or
     substantially all of the Company's assets, or upon any merger or
     consolidation of the Company with or into any other entity, all as though
     such successors and assigns of the Company and their respective successors
     and assigns were the Company. Insofar as the Employee is concerned, this
     Agreement, being personal, may not be assigned.

18.  Severability. To the extent any provision of this Agreement shall be
     invalid or unenforceable, it shall be considered deleted therefrom and the
     remainder of such provision and of this Agreement shall be unaffected and
     shall continue in full force and effect. In furtherance and not in
     limitation of the foregoing, should the duration or geographical extent of,
     or business activities covered by, any provision of this Agreement be in
     excess of that which is valid and enforceable under applicable law, then
     such provision shall be construed to cover only that duration, extent or
     activities which may be validly and enforceable covered.

19.  Notices. All notices, requests and other communications pursuant to this
     Agreement shall be in writing and shall be deemed to have been duly given,
     if delivered in person or by courier, telegraphed, telexed or by facsimile
     transmission or five business days after being sent by registered or
     certified mail, return receipt requested, postage paid, addressed as
     follows:

     If to the Employee

                           F. Kenneth Andrews
                           9 Sandy Drive
                           Acton, Massachusetts 01720


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EMPLOYMENT AGREEMENT                                                     PAGE 8

     If to the Company:

                           Alteon Inc.
                           170 Williams Drive
                           Ramsey, NJ 07446

     with a copy to:

                           Richard J. Pinto, Esq.
                           Smith, Stratton, Wise, Heher & Brennan
                           600 College Road East
                           Princeton, NJ  08540

     Any party may, by written notice to the other in accordance with this
     Section 19, change the address to which notices to such party are to be
     delivered or mailed.

20.  General. Except as otherwise provided herein, the terms and provisions of
     this Agreement and the Stock Option Grant Agreement to be entered into
     between the Employee and the Company shall constitute the entire agreement
     by the Company and the Employee with respect to the subject matter hereof,
     and shall supersede any and all prior agreements or understandings between
     the Employee and the Company, whether written or oral. This Agreement may
     be amended or modified only by a written instrument executed by the
     Employee and the Company. This Agreement may be executed in any number of
     counterparts, all of which, when executed, shall be deemed to be an
     original, and all of which together shall constitute one and the same
     instrument.

     IN WITNESS WHEREOF, the parties have executed this Employment Agreement as
of the day and year first above written.

                                                  ALTEON INC.


                                                   By:  /S/ Kenneth I. Moch
                                                        -------------------
                                                        Kenneth I. Moch
                                                        Chief Executive Officer


                                                   By:  /S/ F. Kenneth Andrews
                                                        ---------------------
                                                        F. Kenneth Andrews