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                                                                  Exhibit 10.22


                  MULTIPROJECT DEVELOPMENT AND SUPPLY AGREEMENT

     THIS MULTIPROJECTS DEVELOPMENT AND SUPPLY AGREEMENT (this "Agreement") is
made and entered into as of the 20th day of December, 2001 between Clariant Life
Science Molecules (Missouri) Inc., a Delaware corporation with an address at
3411 Silverside Road, 200 Rodney Building, Wilmington, Delaware 19810
("Clariant"), and Novirio Pharmaceuticals Inc., a Massachusetts corporation with
an address at 125 Cambridge Park Drive, Third Floor, Cambridge, MA 02140, on
behalf of itself and its affiliates, Novirio Pharmaceuticals Limited and Novirio
SARL ("Novirio"). Clariant and Novirio are sometimes hereinafter referred to as
a Party or Parties.

                              W I T N E S S E T H:

     WHEREAS, Novirio is engaged in the discovery and development of new
therapeutics for the treatment of viral diseases;

     WHEREAS, from time to time, Novirio may require assistance with the process
development and manufacture of such candidates;

     WHEREAS, Clariant is in the business of providing a wide range of process
chemical research, development, regulatory submission, and manufacturing
services, ("Services");

     WHEREAS, Novirio has discussed certain of its areas of interest with
Clariant and is familiar with Clariant's services, and as a result, wishes to
retain Clariant to provide Services and/or Product ("Product", defined generally
below and identified individually in each of the Addenda attached hereto and or
added later by the parties) for use in one or more of Novirio's pharmaceutical
products;

     NOW, THEREFORE, in consideration of the foregoing, the mutual covenants and
undertakings herein set forth, and other good and valuable consideration, due
receipt and sufficiency of which is hereby acknowledged, and intending to be
legally bound hereby, it is agreed by the Parties as follows:

1.   ADDENDA

     Subject to the terms and conditions of this Agreement, Clariant will from
     time to time provide Services or Product as specified by Novirio, agreed to
     by Clariant and set forth in one or more Addenda. Each such Addendum shall
     contain material terms for Services or Product specifically requested by
     Novirio (e.g., product specifications, project objectives, price, term,
     schedule, quantity, deliverables, etc.), shall be executed by both parties
     and shall reference and be an attachment to this Agreement. In the event of
     a variance between the terms and conditions of this Agreement and the terms
     and conditions of any Addendum, the terms and conditions of the Addendum
     will take precedence for purposes of that Addendum only.

2.   PROPRIETARY INFORMATION

     As used in this Agreement, the term "Proprietary Information" shall mean
     all trade secrets, know-how, technical, scientific, financial or business
     or other information of any kind, and all


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     chemical compounds and other tangible material, supplied by either Party to
     the other, and all information derived or generated by the receiving Party
     therefrom. The Parties acknowledge that they have entered into a
     Confidentiality and Non-Disclosure Agreement dated as of September 26, 2001
     ("Confidentiality Agreement"), attached hereto as Exhibit A and made a part
     hereof, and that the terms of such Confidentiality Agreement shall apply to
     the Parties' actions under this Agreement.

3.   INTELLECTUAL PROPERTY

     Clairant shall promptly and fully disclose to Novirio any and all
     inventions, discoveries, know-how or improvements ("Inventions") conceived,
     developed or made by Clariant or any of its employees, agents or
     representatives in the course or as a result of performing the Services
     pursuant to this Agreement or which pertain or relate to Novirio's
     Proprietary Information. All such Inventions, whether or not patentable,
     shall be the sole and exclusive property of Novirio. Clariant agrees to
     execute, without charge to Novirio, irrevocable assignments of all of its
     rights, title and interests therein to Novirio, and to secure such
     irrevocable assignments from any of its employees, agents or
     representatives who have or may have rights, title and interests in such
     Inventions. Clariant further agrees to use reasonable efforts to assist
     Novirio, at Novirio's request and sole expense, to file patent applications
     or other intellectual property protections on such Inventions.

4.   SHIPPING

     Unless otherwise agreed, any materials produced hereunder shall be packaged
     and shipped per Novirio's instructions, at Novirio's expense, and in
     compliance with all applicable shipping regulations.

5.   PAYMENT

     a.   Unless otherwise specifically agreed upon as set forth in any
          Addendum, Clariant will invoice Novirio monthly for Product, Services
          and/or expenses actually incurred. Each such invoice will specify the
          costs and expenses attributable to each addendum, and if applicable,
          each phase of work in such addendum. Such invoices shall be payable
          net thirty (30) days. Upon the expiration of thirty (30) days from the
          date of the invoices, Clariant shall retain a right to assess interest
          at a rate of one and one half percent (1 1/2%) per month.

     b.   All prices quoted are exclusive of taxes such as sales, use, value
          added or similar taxes. Any such taxes, other than taxes on Clariant's
          income or property, whether now in effect or hereafter enacted, shall
          be the responsibility of Novirio.

6.   INDEMNIFICATION

     a.   Except for negligence on the part of Novirio, Clariant assumes all
          responsibility for and holds Novirio harmless from any claims for any
          damage or injury resulting from and during the course of Clariant's
          performance hereunder.

     b.   In the absence of negligence on the part of Clariant, Novirio accepts
          full responsibility for any use of or reliance by any third party on
          any information or materials resulting


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          from Clariant's performance hereunder and holds Clariant harmless from
          any adverse effects or claims resulting from such use or reliance by
          any third party.

     c.   Novirio shall defend, indemnify and hold Clariant harmless from and
          against any and all third party claims that Clariant's operations
          hereunder constitute an infringement of said third party's proprietary
          rights, if such claim arises from technical information or know-how
          provided by or on behalf of Novirio to Clariant.

     d.   Clariant shall defend, indemnify and hold Novirio harmless from and
          against any and all third party claims to the extent Clariant's
          operations hereunder constitute an infringement of said third party's
          proprietary rights, if such claim arises from technical information
          and know-how provided by Clariant, unless developed by Clariant
          specifically on Novirio's behalf and at Novirio's direction hereunder.

7.   WARRANTY

     a.   Clariant warrants that its Product will meet the specifications
          provided by Novirio and agreed to by Clariant.

     b.   Clariant warrants that it will exercise reasonable care and a high
          standard of professional efforts in rendering the Services and/or
          providing the Product to achieve the desired results in accordance
          with accepted and agreed to standards and procedures. In the event of
          an error or omission on Clariant's part causing its performance to be
          unacceptable, and in the absence of gross negligence or intentional
          misconduct by Clariant or any of its employees, agents and
          representatives, the sole and exclusive remedy of Novirio shall be, at
          Novirio's option, either (a) to have the defective performance
          corrected at no additional expense or (b) to receive a refund of or
          credit for that portion of any monies paid or payable by Novirio which
          relates to such defective performance. IN NO EVENT SHALL CLARIANT BE
          LIABLE TO NOVIRIO OR ANY THIRD PARTY FOR ANY INCIDENTAL, CONSEQUENTIAL
          OR SPECIAL DAMAGES OF ANY TYPE OR AMOUNT ARISING OUT OF ITS
          PERFORMANCE OR FAILURE OF PERFORMANCE HEREUNDER.

     c.   CLARIANT MAKES NO OTHER REPRESENTATION OR WARRANTY OF ANY KIND,
          EXPRESS OR IMPLIED, AS TO MERCHANTABILITY, FITNESS FOR PARTICULAR
          PURPOSE OR ANY OTHER MATTER WITH RESPECT TO PRODUCT, whether used
          alone or in combination with other substances.

8.   TERMINATION

     a.   Unless terminated earlier according to Section 8 (b) or (c), this
          Agreement shall continue for a period of five (5) years from the date
          hereof and may be extended by mutual written agreement of the parties.

     b.   Either party may terminate this Agreement and/or any Addendum
          hereunder upon not less than thirty (30) days prior written notice to
          the other for reason of a material breach or default by the other
          party, if such breach or default is not cured within the thirty (30)
          day period after receipt of such written notice.


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     c.   Unless otherwise set forth in an Addendum, Novirio may terminate this
          Agreement and/or any Addendum at its sole discretion at any time by
          giving written notice to Clariant. Such termination shall be effective
          upon the expiration of six (6) months from the date such notice is
          received by Clariant. In the event of such termination, Novirio agrees
          to reimburse Clariant for the following under any terminated Addendum:

          (i)   110% of material and project costs already incurred or
                irrevocably committed to;

          (ii)  the portion of Services provided or to be provided through the
                effective date of termination, on a pro rata basis; and

          (iii) reasonable and unavoidable shutdown, documentation and clean-up
                fees.

9.   INSPECTION

     Novirio has the right upon reasonable notice and during business hours to
     visit Clariant to observe the progress of the work and inspect any data
     relating to the Services.

10.  FORCE MAJEURE

     Neither Party will be responsible for any failure of or delay in
     performance hereunder which may be due, in whole or in part to any
     occurrence, cause or causes beyond its reasonable control, including but
     the failure of third party suppliers to furnish materials ordered by
     Clariant in a timely manner. The performance schedule, if any, shall be
     adjusted to account for any such delays.

11.  ASSIGNMENT

     This Agreement, the obligations arising hereunder and the Services to be
     performed by Clariant in accordance herewith, may not be assigned by
     Clariant, in whole or in part, without the prior written consent of
     Novirio, except to the purchaser of substantially all of Clariant's
     business to which this Agreement relates.

12.  USE OF NAMES

     Neither party shall use or disclose the name of the other in any
     advertising, sales, marketing or other promotional material, without the
     prior written consent of the other.

13.  INDEPENDENT CONTRACTOR

     Clariant has not assumed, and during the term hereof, will not assume any
     obligations which are inconsistent with this Agreement, shall at all times
     perform as an independent contractor, not as an employee or agent of
     Novirio and shall have no right or authority to commit or obligate Novirio
     unless specifically appointed in writing to do so.

14.  INTEGRATION AND WAIVER

     Unless otherwise amended by a writing signed by both parties, this
     Agreement, any Addenda, and the Confidentiality Agreement represent the
     entire understanding of the parties. No waiver of any provision of this
     Agreement, whether by conduct or otherwise, in any one or more instances
     will be deemed to be or be construed as a further or continuing waiver of
     any such provision, or of any other provision or condition of this
     Agreement.


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15.  NOTICES

     Any notices, payments or statements to be made under this Agreement shall
     be made to Clariant Corporation, 4000 Monroe Road, Charlotte, NC 28505,
     Attention: General Counsel; Clariant Corporation, 3411 Silverside Road,
     Wilmington, DE 19810, Attention: Director of Sales; and to Novirio
     Pharmaceuticals, Inc. at 125 Cambridge Park Drive, Cambridge, MA 02140,
     Attention: Senior Director, Pharmaceutics, with a copy to the attention of
     Senior Vice President, Legal & Administration, or to such other address or
     person later designated in writing by the other party for such purpose.

IN WITNESS WHEREOF, the parties hereto have signed this Agreement in duplicate
as of the day and date first written above.

Clariant Life Science Molecules              Novirio Pharmaceuticals, Inc.
(Missouri) Inc.

    /s/ Mark H. Witterholt                       /s/ Scot M. Barry
By: ________________________________         By:________________________________
    Mark H. Witterholt                          Scot M. Barry

Title:______________________________         Title:_____________________________
      Director of Sales & Marketing                Sr. Director, Pharmaceuticals

Date:_______________________________         Date:______________________________



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