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                                                                   Exhibit 10.11

ALTEON

                                                        Alteon Inc.
                                            170 William Drive - Ramsey, NJ 07446
                                             (201) 934-5000- Fax (201) 934-8880

                             DISTRIBUTION AGREEMENT

THIS AGREEMENT is made this 25th day of September, 1995 by and between ALTEON
INC. of 170 Williams Drive, Ramsey, New Jersey 07446, USA (hereinafter called
"Alteon") of the one part and ERYPHILE BV of Marten Meesweg 51, 3068 AV
Rotterdam, the Netherlands (hereinafter called "Eryphile") of the other part

WHEREAS :

(A)      Alteon has developed and is the owner of the proprietary rights to the
         Product (as hereinafter defined), and

(B)      Alteon and Eryphile desire to enter into an agreement pursuant to which
         Eryphile will have the sole and exclusive right to market, distribute
         and sell such Product in the Territory (as hereinafter defined)

NOW, THEREFORE, in consideration of the mutual covenants herein contained and
for good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, THE PARTIES HERETO AGREE as follows :

Grant and Acceptance of Rights

  1.01   Alteon, subject to the terms and conditions of this Agreement, hereby
         grants to Eryphile the sole and exclusive right to purchase the Product
         for re-sale in the Territory (as such terms "Product" and "Territory"
         are defined in Section 2), and Eryphile accepts such appointment. Said
         appointment shall mean that Alteon shall not appoint any third party
         for the promotion, distribution or sale of the Product (whether under
         Alteon's own or any other trademarks) in the Territory, and shall not
         itself distribute or sell the same in or to the Territory. Alteon shall
         refer to Eryphile all contacts for the sale of and any enquiries
         relating to the Product in the Territory.

  1.02   Eryphile shall be an independent contractor under this Agreement.
         Except as otherwise provided in this Agreement or expressly agreed
         between the parties hereafter in writing, Eryphile is not authorised
         to: (i) enter into agreements for or on behalf of Alteon; (ii) create
         any obligation or liability, express or implied, for or on behalf of
         Alteon; (iii) accept settlement of any debt or other obligation due or
         owed to Alteon; (iv) accept service of process for Alteon; or (v) bind
         Alteon in any manner or thing whatsoever; and Eryphile shall not list,
         print or display Alteon's name in such manner as to indicate or imply
         that there is an employer-employee or principal-agent relationship
         between Alteon and Eryphile. Distribution Agreement Page 2
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 2

  1.03   Subject to its material compliance with all applicable laws and
         regulations and except as otherwise provided in this Agreement,
         Eryphile shall have full control over the manner and means of
         performing its obligations hereunder. All expenses incurred by Eryphile
         in connection with the performance of such obligations, including the
         appointment and remuneration of employees, agents or representatives,
         shall be the sole responsibility of Eryphile.

2.       Product and Territory

  2.01   The Product is described in Exhibit A hereto, and includes any and all
         ancillary products relating thereto and any and all modifications,
         improvements, developments or replacements of or appertaining to such
         Product except that the Product shall in all events be therapeutic
         dosage forms only in finished product form only. The parties from time
         to time by mutual agreement in writing may add to such Exhibit any
         other existing or future product of Alteon.

  2.02   The "Territory" shall consist of the countries specified in Exhibit B
         hereto and such other countries (if any) as the parties from time to
         time to time may add to such Exhibit by mutual agreement in writing.

  2.03   Eryphile is not acquiring any rights to the Product outside the
         Territory. Accordingly, Eryphile shall not sell any Product to anyone
         outside the Territory, and shall not sell any Product to anyone in the
         Territory who either Eryphile or Alteon has reasonable grounds to
         believe might resell it outside the Territory or might permit any
         Product obtained by it to be transported outside the Territory.

  2.04   Alteon is and will at all times be the owner of all rights to the
         Product, including registrations with governmental authorities in the
         Territory, except for the distribution rights granted pursuant to this
         Agreement.

3.       Promotion and Sale of Product

  During the term of this Agreement:

  3.01   Eryphile shall use its best efforts in the registration and related
         clinical testing, promotion, distribution and sale of the Product in
         the Territory. Such efforts in Israel and South Africa shall not be
         less than the efforts which it devotes to new products of comparable
         commercial promise in countries with comparable market opportunities.

  3.02   Eryphile shall organize and maintain a competent promotional and
         selling organization for the Product in the Territory, and hold an
         inventory of the Product sufficient to meet market demand therefor in
         the Territory without undue delay.
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 3

  3.03   Alteon shall provide Eryphile with reasonable quantities of such
         English-language promotional and advertising material as it from time
         to time shall have available on the Product. On the basis of such
         material, Eryphile shall be responsible for the preparation of such
         local-language promotional and advertising material as may be required,
         such material to be subject to the reasonable prior approval of Alteon.
         Alteon shall also provide Eryphile with such quantities of samples of
         the Products as from time to time shall be reasonably agreed between
         the parties.

  3.04   Eryphile shall refer to Alteon all enquiries for the Product from
         outside the Territory.

  3.05   Alteon undertakes to provide Eryphile as and when appropriate with
         scientific, technical and clinical advice and information in relation
         to the Product, and to respond promptly and constructively to enquiries
         or recommendations made from time to time by Eryphile, whether on its
         own initiative or at the request of opinion leaders or other interested
         parties in the Territory, concerning the use of the Product or possible
         improvements or modifications thereof.

  3.06   Eryphile shall comply with all health registration laws, regulations
         and orders of any government authority within the Territory and with
         all other governmental requirements applicable to its sales activities
         with respect to the Product. Alteon shall furnish Eryphile with such
         assistance and cooperation as may reasonably be requested in connection
         with compliance with such governmental requirements, including without
         limitation the file of clinical and other data and such samples of the
         Product or its active ingredients as may be required for registration
         purposes. Eryphile shall also use its best efforts to obtain, at its
         own expense, any import license, foreign exchange permit, or other
         permit or approval it may need for the performance of its duties under
         this Agreement. In particular and whenever appropriate, Eryphile will
         proceed expeditiously to take all such steps as shall be reasonably
         necessary to obtain regulatory approval for each and every new
         application or therapeutic dosage form of the Product, including the
         conduct, at Eryphile's expense, of further clinical trials or similar
         procedures within the Territory to the extent (if any) required in each
         case. All registrations, licences, permits and other government
         approvals and filings relating to the Product shall specify that Alteon
         is the owner of the Product and of the registrations and all other
         rights to the Product except for the distribution rights granted
         pursuant to this Agreement.

  3.07   The Product shall be packaged and labelled for distribution and sale in
         the Territory in accordance with local law in a manner to be mutually
         agreed between the parties. Eryphile shall be entitled to have included
         on such packaging and labelling an indication that it is the
         territorial source of the Product.
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 4

  3.08   Eryphile undertakes not, without the prior written consent of Alteon,
         to promote and sell in the Territory any product which is used for the
         same therapeutic purpose as the Product.

4.       Planning & Minimum Standards

  4.01   Prior to 30th September of each year during the continuance of this
         Agreement, Eryphile will submit to Alteon a plan for the marketing,
         distribution and sale of the Product in the Territory during the next
         calendar year (hereinafter referred to as "the Plan"), the first such
         Plan to be annexed to this Agreement.

  4.02   The Plan will include, on a country by country basis, Eryphile's
         forecasted sales and marketing programme for the relevant year in
         respect of each therapeutic dosage form of the Product and will propose
         for such year in relation to Israel and South Africa respectively:

         4.2.1    a minimum purchase quota (hereinafter referred to as the
                  "Minimum Quota"), and

         4.2.2    a minimum program of marketing efforts (hereinafter referred
                  to as the "Minimum Program").

  4.03   The Minimum Quotas and Minimum Programs for the said countries for each
         calendar year will be finally established by mutual agreement between
         the parties prior to the first day of the relevant year, failing which
         an expert shall be appointed to resolve the open issues outstanding
         between the parties, such expert to be named by mutual agreement of the
         parties or, failing which and at the request of either party, by the
         Secretary-General of the International Chamber of Commerce.

  4.04   It is agreed with respect to Minimum Quotas that

         4.4.1    they shall not exceed seventy per cent (70%) of reasonable
                  full purchase forecasts for the countries respectively
                  concerned for each relevant year;

         4.4.2    in the fixing of Minimum Quotas in accordance herewith,
                  reasonable regard shall be taken of the sales of the Product
                  by Alteon or Alteon licensees in other comparable markets,
                  according to the guidelines included in Exhibit B hereto.

  4.05   In the event that, in any calendar year, Eryphile shall fail in either
         Israel or South Africa to meet both the applicable Minimum Quota and
         Minimum Program, Alteon shall be entitled within ninety (90) days of
         the end of such year to serve a written
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 5

         notice upon Eryphile, removing the country in question from the
         Territory with effect 120 days from the date of such notice, provided
         however that if Eryphile places orders with Alteon for Product within
         such 120 days, for delivery within 90 days, in quantities equal to or
         greater than the shortfall from the Minimum Quota during the prior
         calendar year plus any shortfall from the pro rata portion of the
         Minimum Quota for the current calendar year, such notice shall not take
         effect and that country shall remain within the Territory.

  4.06   In the event that Eryphile is no longer distributing the Product in
         either Israel or South Africa, its distribution rights for Bulgaria,
         Cyprus and Jordan shall be terminated and this Agreement shall be
         terminated.

5.       Prices and Terms of Sale

  5.01   The price from Alteon to Eryphile for the Product will be established
         by Alteon, in reasonable consultation with Eryphile, once the Product
         is approved for sale in Israel. Alteon may change said price from time
         to time upon giving Eryphile written notice of the change at least
         ninety (90) days in advance of the effective date thereof. The new
         price will apply to all orders accepted by Alteon after said effective
         date, and also to orders accepted by Alteon prior to such date in the
         case of any quantities of the Product ordered for shipment more than
         ninety (90) days after that date. Alteon agrees, notwithstanding the
         foregoing, that the prices charged by it to Eryphile shall not exceed
         Alteon's lowest prices to other distributors for similar quantities.

  5.02   Alteon will use reasonable commercial efforts to meet each order for
         the Product placed by Eryphile on or before the requested shipment
         date, provided such date is at least sixty (60) days from the date on
         which Alteon receives the order. Orders from Eryphile shall be deemed
         accepted by Alteon unless rejected in writing within fourteen (14) days
         of receipt of order. Alteon reserves the right to specify a different
         reasonable shipment date by written notice to Eryphile given within
         such fourteen (14) days' period, failing which the shipment date
         requested by Eryphile shall be deemed accepted. Shipments shall be made
         pursuant to Eryphile's instructions; all deliveries shall be properly
         packed for overseas shipment. It is understood that Eryphile may use
         its normal purchase order form with respect to its purchases of the
         Product, which form may specify (inter alia) the quantity of the
         Product ordered, the method of shipment, the requested shipment
         date(s), and the destination to which shipment is to be made. Such form
         shall be used for convenience only, however, and any terms or
         conditions on such form which are inconsistent with the terms and
         conditions of this Agreement shall have no force or effect whatsoever
         as between the parties, regardless of whether Alteon might otherwise be
         deemed to have accepted such form by reason of its acknowledgement or
         execution thereof.
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 6

  5.03   All payments due to Alteon from Eryphile for the Product hereunder
         shall be payable in US Dollars within ninety (90) days of date of
         invoice to such bank account as Alteon from time to time may designate.
         The terms of sale shall be FOB Alteon's warehouse. Eryphile agrees to
         pay and to hold Alteon harmless from all import duties, sales, use,
         excise or other taxes, and all costs of transportation, brokerage,
         handling and insurance, applicable to the delivery of the Product
         hereunder from point of shipment.

  5.04   During the term of this Agreement, if Eryphile so requests, Alteon will
         give reasonable consideration to modification of this Agreement to
         provide for the supply of Product in bulk form for repackaging in final
         dosage form by Eryphile, provided Alteon deems such arrangement to be
         in the best interests of both parties under terms and conditions
         acceptable to Alteon.

6.       Term of Agreement and Termination

  6.01   Subject to earlier termination as provided for in this Section 6, this
         Agreement shall be for an initial period commencing on the date hereof
         and ending on the last day of the tenth (10th) year following the date
         upon which regulatory approval is issued for the sale of the Product in
         Israel. Thereafter, this Agreement shall automatically continue for
         further consecutive periods of three (3) years each, unless and until
         it is terminated on the last day of said initial period or of any such
         further period by one party serving upon the other party not less than
         one hundred and twenty (120) days' prior written notice to such effect.

  6.02   In the event of a material default by either party in the performance
         of any of its obligations under this Agreement, the other party shall
         have the right to give written notice to the defaulting party advising
         such party of the default involved. If the defaulting party shall not
         have remedied such default within ninety (90) days (or, in the case of
         the breach of a financial obligation, 30 days) after receipt of such
         notice, the other party shall have the right, in addition to any other
         rights or remedies it may have, to terminate this Agreement immediately
         upon giving a further written notice to the defaulting party.

  6.03   Either party may immediately terminate this Agreement at any time by
         giving written notice of such termination in the event that the other
         party is adjudged insolvent or institutes or permits to be instituted
         against it (without a dismissal thereof within 90 days) any proceedings
         in consequence of debt under any applicable law.

  6.04   Upon the effective date of termination of this Agreement for whatever
         reason, the right of Eryphile to promote, distribute and sell the
         Product in the Territory shall cease. Thereupon, Alteon shall
         re-purchase Eryphile's outstanding stock of the
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 7

         Product in saleable condition at a price equivalent to Eryphile's
         landed cost therefor, FOB Eryphile's warehouse, provided, that Alteon
         shall not be required to purchase more than 50% of the amount of
         Product sold by Eryphile in the previous 12 months, and further
         provided that Alteon shall have no obligation to re-purchase any
         Product if the termination of this Agreement is on account of a breach
         of contract by Eryphile.

  6.05   Alteon shall continue to meet Eryphile's orders for the Product placed
         prior to the effective date of termination hereof, but no termination
         of this Agreement shall in any manner whatsoever release, or be
         construed as releasing, either party from any liability to the other
         arising out of or in connection with such party's breach of or failure
         to perform any covenant, undertaking or obligation contained in this
         Agreement.

7.       Warranties

         Alteon warrants that the Product will be manufactured in accordance
         with generally accepted good manufacturing practices in the
         pharmaceutical industry, will meet its specifications and will be free
         from defects in materials or workmanship. Alteon shall promptly replace
         any Product found to be defective without charge or expense to
         Eryphile. Any such defective Product shall, at Alteon's election and
         cost, be either returned to Alteon or destroyed.

         Alteon makes no other warranty of any kind and excludes and disclaims,
         to the extent permitted by applicable law, any and all implied
         warranties, including (without limitation) those concerning the
         merchantability of the Product or its suitability for any particular
         purpose or use. Alteon excludes, in particular, any liability for
         indirect or consequential damages.

         Should Eryphile make any warranty or representation inconsistent with
         or in addition to the warranties of Alteon stated in this Section 7,
         Eryphile shall at its own expense defend and hold harmless Alteon from
         any claim to the extent it is based upon such inconsistent or
         additional warranty or representation.

8.       Trademarks and Trade Names

  8.01   Eryphile recognizes the validity of Alteon's trademarks and trade names
         as set forth in Exhibit C hereto and such other trademarks and trade
         names as Alteon may designate for the Product, acknowledges that the
         same are the property of Alteon, and agrees not to infringe upon, harm
         or contest the rights of Alteon to its trademarks and trade names.
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 8

  8.02   Eryphile shall not use any of Alteon's trademarks or trade names,
         except in conformity with this Agreement or as otherwise approved in
         writing by Alteon. Eryphile shall not use Alteon's trademarks or trade
         names in connection with any products other than the Product, but shall
         have the right during the continuance hereof to use the same in
         connection with the Product.

  8.03   Eryphile agrees that upon termination of this Agreement for any reason
         it will destroy or, at Alteon's option, return to Alteon any
         advertising, promotional or other materials bearing any of Alteon's
         trademarks or trade names.

  8.04   Alteon shall take prompt action at its expense to stop all
         infringements in the Territory of its trademarks and trade names
         (including court actions, if necessary) whenever it determines such to
         be commercially reasonable. If Alteon decides that it would not be
         commercially reasonable to take such action, Eryphile may do so, at its
         expense, in the names of both Alteon and Eryphile.

9.       Intellectual Property Claims

         Alteon will defend, indemnify and hold harmless Eryphile against any
         and all third party claims of patent, trademark or other intellectual
         property infringement which may be asserted against Eryphile because of
         its marketing, advertising or sale of the Product in the Territory
         (except for claims of infringement of a trade name or trademark other
         than one covered by this Agreement). In such event, Alteon will bear
         all losses, damages, costs and expenses suffered or incurred by
         Eryphile in connection with any such claim and the defense thereof, or
         as a result of any settlement made or judgement rendered on the basis
         of such claim. Alteon shall have sole and exclusive control of the
         defense of any such claim and shall have the right to settle or
         compromise any claims on terms acceptable to Alteon. Notwithstanding
         the provisions of Section 6 of this Agreement, Alteon shall have right,
         upon notice to Eryphile, to withdraw the affected dosage form or forms
         of the Product from sale for any country for which such claim is made
         and to amend this Agreement accordingly.

10.      Product Liability Claims

         Alteon shall defend, indemnify and hold harmless Eryphile against any
         and all product liability claims arising out of the use of the Product,
         except to the extent that such claims arise out of or relate to
         mishandling (including improper storage), modification or misuse of the
         Product, product claims which were not expressly approved by Alteon, or
         other negligence or wrongful action or inaction by Eryphile, its
         employees or agents. Eryphile shall give Alteon prompt notice of every
         complaint, claim or suit known to Eryphile concerning the Product, keep
         Alteon fully informed of the status of each, and afford Alteon
         reasonable access to its
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                                                                   Exhibit 10.11

Distribution Agreement                                                    Page 9

         records pertaining to such complaint, claim or suit. Alteon shall have
         the right to defend and control the defense of, or to settle, any such
         claim. Eryphile shall have the right, at its own expense, to
         participate in any such defense action or settlement negotiations.

         Eryphile shall likewise defend, indemnify and hold harmless Alteon as
         to any product liability claims arising out of the use of the Product
         in the Territory to the extent that such claims arise out of or relate
         to mishandling (including improper storage), modification or misuse of
         the Product, product claims which were not expressly approved by
         Alteon, or other negligence or wrongful action or inaction by Eryphile,
         its employees or agents.

11.      Confidential Information

         Each party agrees that it will treat in the strictest confidence all
         oral and written communications from the other party which are
         designated, or which should reasonably be regarded in a normal
         commercial view, as constituting business secrets or proprietary
         information (hereinafter referred to as "Proprietary Information").
         Each party agrees to refrain from disclosing or making available to any
         third party and to refrain from using for any purpose other than the
         implementation of the Agreements between the parties any of the other
         party's Proprietary Information without such other party's prior
         written consent. Each party also agrees to reveal Proprietary
         Information only to those persons who have a need to know it in
         connection with the implementation of such Agreements and who are
         required to keep it confidential, and to impose upon its respective
         affiliates, employees and agents the same obligations with respect to
         said other party's Proprietary Information as it employs with respect
         to its own confidential information. The provisions of this Section
         shall survive the termination of this Agreement.

         Proprietary Information hereunder shall not, however, include
         information

         (i)      which is in or enters the public domain through no breach of
                  this Agreement, or

         (ii)     which is known to the party receiving the same at the time of
                  disclosure, as evidenced by such party's prior written
                  records, or

         (iii)    which such party may receive from a third party lawfully
                  entitled to disclose the same.
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                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 10

12.      Miscellaneous Provisions

  12.01  Rights Cumulative

         Each and all of the respective rights and remedies of the parties
         hereunder shall be considered to be cumulative with and in addition to
         any other rights or remedies which such parties may have at law or in
         equity in the event of the breach of any of the terms of this
         Agreement. The exercise or partial exercise of any right, power or
         remedy shall neither constitute the exclusive election thereof, nor the
         waiver of any other right or remedy available to either party.

  12.02  Notices

         Any notice or other formal communication which either party may wish or
         be required to serve on the other party in connection with this
         Agreement shall be in writing and may be delivered by personal service
         or sent by registered or certified air mail, return receipt requested,
         with postage fully prepaid, provided that a copy of every such notice
         sent by mail shall be simultaneously transmitted by telefax.

         Notices shall be addressed as follows:

         If to Alteon:

         ALTEON Inc.
         170 Williams Drive
         Ramsey, NJ 07446 USA

         Telefax No: 1 - 201 - 934 0090

         If to Eryphile:

         ERYPHILE BV
         P.O.Box 2295
         3000 CG Rotterdam
         The Netherlands

         Telefax No: 31 - 20 - 661 0654

         Either party may from time to time, by notice in writing served upon
         the other as provided above, designate a change of address for the
         service of notices.

         Nothing contained in this Agreement shall excuse either party from
         giving oral notice to the other when prompt notification is
         appropriate, but such notice shall not satisfy the requirement of
         written notice as specified in this Section.
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                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 11

  12.03  Severability

         If any provision of this Agreement is held to be void or unenforceable
         by or as a result of the decision of any court or other authority,
         which decision is binding upon the parties, the parties agree that such
         decision shall not result in the nullity or unenforceability of the
         remaining provisions of this Agreement. The parties further agree to
         use their mutual best efforts to replace such void or unenforceable
         provision in a manner which will achieve, to the extent possible, the
         economic, business and other purposes of said void or unenforceable
         provision.

  12.04  Force Majeure

         No failure to observe any of the terms or conditions of this Agreement
         shall be deemed to be a breach of this Agreement, if the same is caused
         by or arises out of one or more of the following conditions, namely:
         acts of God; acts, regulations or laws of any government or similar
         authority; war; civil commotion; destruction of facilities or materials
         by fire, earthquake or storm; labor disturbances; epidemics; failure of
         public utilities or of suppliers; or any other event, matter or thing
         wheresoever occurring and whether or not of the same class or kind as
         those set forth above, which is not reasonably within the control of
         the affected party. However, the parties shall endeavor to avoid or
         cure all such conditions, and any party temporarily excused from
         performance by such conditions shall resume performance promptly when
         such conditions are removed. Any party claiming any such conditions as
         an excuse for delay in performance shall give prompt notice in writing
         of such conditions to the other party. The parties, furthermore, while
         any such conditions shall prevail, will cooperate by reasonable mutual
         agreement to minimize the effects of such conditions by adopting any
         suitable temporary measures which may be available to them.

  12.05  Choice of Law

         The internal laws of the State of New Jersey, without reference to any
         principles concerning conflicts of law, shall govern the validity of
         this Agreement, the construction of its terms and the interpretation of
         the rights and duties of the parties hereunder.

  12.06  Arbitration

         Any dispute or claim in any way arising out of or relating to this
         Agreement shall be finally settled by arbitration under the Rules of
         Conciliation and Arbitration of the International Chamber of Commerce.
         In the event that the request for arbitration shall be submitted by
         Alteon, the arbitration shall be held in Tel-Aviv, Israel, and in the
         event that such request shall be made by Eryphile, the arbitration
         shall take
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                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 12

         place in New Jersey, USA. The language to be used in the proceedings
         shall be English, and each party shall bear one half of the costs of
         the arbitration. The decision of the arbitrator(s) shall be definitive,
         binding and without appeal, and judgement upon the award rendered may
         be entered in any court of competent jurisdiction.

  12.07  Interpretation

         (i)      The headings used at the beginnings of the Sections and
                  certain sub-sections of this Agreement are for convenience
                  only and form no part hereof. They are not to serve as a basis
                  for interpretation or construction of this Agreement, nor as
                  evidence of the intention of the parties.

         (ii)     References in this Agreement to the plural shall where the
                  context so admits include the singular, and vice versa.

  12.08  Counterparts

         This Agreement may be executed in separate counterparts, each of which
         shall be deemed an original and, when executed separately or together,
         shall constitute a single original instrument, effective in the same
         manner as if the parties had executed one and the same instrument.

  12.09  Waiver

         No waiver of any term or condition of this Agreement, whether by
         conduct or otherwise, in any one or more instances shall be deemed to
         be, or construed as a further or continuing waiver of any such term or
         condition, or as a waiver of any other term or condition of this
         Agreement.

  12.10  Entire Agreement

         This Agreement and the Clinical Testing Agreement between the parties
         of even date herewith are intended by the parties to be the final
         expression of their agreement as to the subject matter herein and
         therein, and constitute the entire understanding between them with
         respect thereto. They are a complete and exclusive statement of the
         terms and conditions of such understanding, and shall supersede any and
         all prior correspondence, conversations, negotiations, understandings
         or agreements relating to the same subject matter.
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                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 13

  12.11  Amendments

         No change in, modification of or addition to the terms conditions
         contained in this Agreement shall be valid unless set forth in a
         written document signed by both parties, which specifically states that
         it constitutes an amendment hereto.

  12.12  Assignment

         Neither party to this Agreement shall assign or otherwise transfer any
         of its rights or obligations hereunder to any third party without the
         prior written approval of the other party, except that

         (a)      Alteon may assign any or all of its rights and obligations
                  hereunder to an Affiliate (as hereinafter defined), and

         (b)      Eryphile may delegate or assign any or all of its rights and
                  obligations hereunder to an Affiliate (as hereinafter defined)
                  resident in the Territory, provided that

         (c)      The Affiliate agrees in writing with the parties that it will
                  be bound by all of the terms of the Agreement which impose
                  obligations upon its assignor, and

         (d)      The assigning party will remain fully responsible for the
                  performance of the Affiliate to which it assigns its rights.

         "Affiliate" for the purposes hereof means a company controlling,
         controlled by or under common control with the party concerned,
         "control" meaning the holding of more than fifty per cent (50%) of the
         common voting stock or voting equity share capital of the relevant
         company.

         Eryphile, moreover, shall be entitled to engage sub-distributors in
         connection with its performance hereunder, but only upon terms and
         conditions which are consistent in all respects with those of this
         Agreement.

         Furthermore, Alteon may assign all of its rights and obligations
         hereunder without approval to any party to whom Alteon sells its
         related business assets.

  12.13  Successors and Assigns

         This agreement and all of its terms and conditions are intended to be
         fully effective and binding, to the extent permitted by applicable law,
         upon the successors and permitted assigns of the parties (including, in
         the case of Alteon, any successor in title to assets of Alteon which
         include rights in relation to the Product).
<PAGE>   14
                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 14

  12.14  Exhibits

         All exhibits referred to in and attached to this Agreement are intended
         to be a part of this Agreement as if set forth in full in the text
         hereof.


IN WITNESS WHEREOF, this Agreement has been signed by the duly authorized
signatories of the parties hereto the day and year first before written,


         ALTEON INC.                                 ERYPHILE BV



by: /s/ James J. Mauzey                           by:
    -------------------                              ---------------------------
      James J. Mauzey                                      Director

Title: Chairman and  Chief Executive Officer
                                                     ---------------------------
                                                           Director
<PAGE>   15
                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 15



                                    EXHIBIT A

                                     Product



                                   PIMAGEDINE

                      all dosage forms for therapeutic uses

            (including all existing and future indications therefor)





                                    EXHIBIT B

                                    Territory


                           Israel   (including Israeli-administered territories
                                    and the areas of Palestinian autonomy and
                                    any future political denominations of such
                                    territories and areas)

                           Bulgaria
                           Cyprus
                           Jordan
                           South Africa




  NOTE:   Guidelines for the fixing of Minimum Quotas

                  (a)      in respect of Israel, the comparable market to be
                           taken into account is Italy, and

                  (b)      in respect of South Africa (to the extent of that
                           proportion of its population enjoying a standard of
                           living equivalent to that prevailing in Western
                           Europe), such comparable market is the United
                           Kingdom,

                  on a per capita basis in each case.
<PAGE>   16
                                                                   Exhibit 10.11

Distribution Agreement                                                   Page 16













                                    EXHIBIT C

                            Trademarks & Trade Names




                                     ALTEON

                                   PIMAGEDINE

                    trademark for Pimagedine to be determined