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                                                                    Exhibit 10.5

                                  PROTEO, INC.


                         COMMON STOCK PURCHASE AGREEMENT
                         -------------------------------


This Common Stock Purchase Agreement ("Agreement") is made this 22nd day of
December, 2006 by and between PROTEO, INC., a Nevada corporation with its
principal place of business at 2102 Business Center Drive, Irvine, CA 92612 (the
"Company") and the Purchaser of its stock, FIDEsprit AG, a Swiss corporation
with its principal place of business at Rosengartenstr. 4, CH-8608 Bubikon,
Switzerland ("Purchaser").


                                    RECITALS
                                    --------

A.      The Company is engaged in research and development of pharmaceuticals.
        The Company now is willing to sell shares of its common stock, on terms
        as stated herein.

B.      The Company has authorized 300,000,000 shares of common stock and
        10,000,000 shares of preferred stock. Currently, 22,379,350 shares of
        the Company's common stock are issued and outstanding. As of the date
        hereof, no preferred stock has been issued.

C.      Purchaser and the Company now mutually desire for Purchaser to purchase
        1,500,000 shares of the Company's common stock at the price per share
        determined herein, on the terms and conditions stated herein.

                                    AGREEMENT
                                    ---------

In consideration of the mutual promises, representations, warranties and
conditions set forth in this Agreement, the Company and Purchaser agree as
follows.

1. Purchase and Sale of Shares.

         1.1      SALE OF SHARES. The Company has authorized the issuance and
                  sale of 1,500,000 shares. (the "Purchase Shares") under this
                  Agreement.

         1.2      PRICE PER SHARE. The price per share shall be $0.60 per share,
                  totaling to $900,000 for the Purchase Shares.

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                  In reliance upon Purchaser representations and warranties
                  contained in Section 4 hereof, and subject to the terms and
                  conditions set forth herein, the Company hereby agrees to sell
                  to Purchaser shares of the Company's common stock.


2.       CLOSING: ISSUANCE AND DELIVERY OF SHARES: CONDITIONS.

         2.1      CLOSING(S). The closing of the sale under this Agreement (the
                  "Closing"), shall be held within five (5) working days upon
                  the date of the Agreement ("Closing Date"), at the offices of
                  the Company or on such earlier date or at such other place as
                  the Parties may agree.

         2.2      PAYMENT OF PURCHASE PRICE. At the Closing session, the
                  Purchaser shall deliver appropriate promissory note for the
                  payment of the purchase price as determined in paragraph 1.2.
                  payable in five (5) equal monthly installments in the amount
                  of $180,000 each, the first falling due upon issuance of the
                  Purchase Shares, the second falling due on March 31, 2007, the
                  third on June 30, 2007, the fourth on September 30, 2007 and
                  the last falling due on December 31, 2007. Any payment shall
                  be in United States funds by check, cash, by wire transfer or
                  by other means of payment as shall have been agreed upon by
                  the Purchasers and the Company prior to payment.

         2.4      ISSUANCE AND DELIVERY. At the Closing session, subject to the
                  terms and conditions hereof, the Company shall deliver an
                  irrevocable instruction to the Company's secretary to issue
                  and deliver to Purchaser appropriate stock certificates,
                  registered in the name of the Purchaser for the Shares, or his
                  designee.

3.       REPRESENTATIONS AND WARRANTIES OF THE COMPANY.

The Company hereby represents and warrants to Purchasers as of the date hereof
as follows, and all such representations and warranties shall be true and
correct as of any Closing Date as if then made and shall survive the Closing.

          3.1     ORGANIZATION. The Company is a corporation, duly incorporated,
                  validly existing and in good standing under the laws of
                  Nevada. The Company has all requisite power and authority to
                  own or lease its properties and to conduct its business as now
                  conducted. The Company holds all licenses and permits required
                  for the conduct of its business as now conducted, which, if
                  not obtained, would have a material adverse effect on the
                  business, financial condition or results of operations of the


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                  Company taken as a whole. The Company is qualified as a
                  foreign corporation and is in good standing in any states
                  where the conduct of its business or its ownership or leasing
                  of property requires such qualification, except where the
                  failure to so qualify would not have a material adverse effect
                  on the business, financial condition or results of operations
                  of the Company taken as a whole.

         3.2      CAPITALIZATION. The Company is authorized to issue 300,000,000
                  shares of Common Stock of which 22,379,350 shares are
                  outstanding at the date of this Agreement. All of the issued
                  and outstanding shares of Common Stock on the Closing Date are
                  or will have been duly authorized, validly issued and then
                  fully paid and non-assessable. The Company's right to issue
                  shares of its stock otherwise shall not be limited by any
                  provision herein.

         3.3      AUTHORITY. The Company has all requisite power and authority
                  to enter into this Agreement, and to consummate the
                  transactions contemplated hereby and thereby. The execution
                  and delivery of this Agreement, and the consummation of the
                  transactions contemplated hereby and thereby have been duly
                  authorized by all necessary corporate action on the part of
                  the part of the Company, and upon their execution and delivery
                  by the Company, such documents will constitute valid and
                  binding obligations of the Company, enforceable against the
                  Company in accordance with their terms.

         3.4      ISSUANCE OF SHARES. The Shares, when issued pursuant to the
                  terms of this Agreement, will be duly and validly authorized
                  and issued, fully paid and non-assessable.

         3.5      NO CONFLICT WITH LAW OR DOCUMENTS. The execution, delivery and
                  consummation of this Agreement, and the transactions
                  contemplated hereby and thereby, will not (a) conflict with
                  any provisions of the Certificate of Incorporation or Bylaws
                  of the Company; (b) result in any violation of or default or
                  loss of a benefit under, or permit the acceleration of any
                  obligation under (in each case, upon the giving of notice, the
                  passage of time, or both), any mortgage, indenture, lease,
                  agreement or other instrument, permit, franchise license,
                  judgement, order, decree, law, ordinance, rule or regulation
                  applicable to the Company.

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         3.6      CONSENTS, APPROVALS AND PRIVATE OFFERING. Except for any
                  filings required under Federal and applicable state securities
                  laws, all of which shall have been made as of the Closing Date
                  to the extent required as of such time, no permit, consent,
                  approval, order or authorization of, or registration,
                  declaration or filing with, any Federal, state, local or
                  foreign governmental authority is required to be made or
                  obtained by the Company in connection with the execution and
                  delivery of this Agreement, and the consummation of the
                  transactions contemplated hereby and thereby.

4.       REPRESENTATIONS AND WARRANTIES OF PURCHASERS.

Each Purchaser hereby represents, warrants and covenants with the Company as
follows:

         4.1      LEGAL POWER. Such Purchaser has the requisite power, as
                  appropriate, and is authorized to enter into this Agreement,
                  to purchase the Shares hereunder, and to carry out and perform
                  his, her or its obligations under the terms of this Agreement.

         4.2      DUE EXECUTION. This Agreement has been duly authorized,
                  executed and delivered by each Purchaser, and, upon due
                  execution and delivery by the Company, this Agreement will be
                  a valid and binding agreement of each Purchaser.

         4.3       INVESTMENT REPRESENTATIONS.

                  Purchaser represents and agrees that:

                  4.3.1    Purchaser is acquiring the Shares for its own
                           account, not as a nominee or agent, for investment
                           and not with a view to or for resale in connection
                           with, any distribution or public offering thereof
                           within the meaning of the Securities Act of 1933, as
                           amended (the "Act"), except pursuant to an effective
                           registration statement under the Act;

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                  4.3.2    Purchaser is a professional and an 'accredited
                           investor,' as that term is defined in Rule 501 (a) of
                           Regulation D promulgated under the Act. Each
                           Purchaser has such knowledge and experience in
                           financial and business matters that they are fully
                           able to evaluate the merits and risks of the
                           acquisition of the Securities, and have conducted
                           their own investigation into the suitability of its
                           investment, and reviewed all the information that
                           they consider necessary to evaluate their acceptance
                           of the Securities. Each Purchaser is able to bear the
                           risks associated with accepting the Securities,
                           including the risk of loss of the entire investment
                           in the Securities. Purchaser has received and
                           reviewed any and all information Purchaser deemed
                           necessary to evaluate its investment.

                  4.3.3    Purchaser understands that the Shares have not been
                           registered under the Act by reason of a specific
                           exemption therefrom, and may not be transferred or
                           resold except pursuant to an effective registration
                           statement or exemption from registration and each
                           certificate representing the Shares will be endorsed
                           with the following legend:

                           (i)  THE SECURITIES REPRESENTED BY THIS CERTIFICATE
                                HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
                                ACT OF 1933, AS AMENDED (THE "ACT"). THE SHARES
                                HAVE BEEN ACQUIRED FOR INVESTMENT AND MAY NOT BE
                                SOLD, TRANSFERRED, ASSIGNED OR OTHERWISE
                                DISPOSED OF IN THE ABSENCE OF A CURRENT AND
                                EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT
                                WITH RESPECT TO SUCH SHARES, OR AN OPINION OF
                                THE ISSUER'S COUNSEL TO THE EFFECT THAT
                                REGISTRATION IS NOT REQUIRED UNDER THE ACT; and

                           (ii) Any legend required to be placed thereon by
                                applicable federal or state securities laws.

5.       TERM AND TERMINATION

         5.1      TERM. This Agreement shall expire upon total purchase of
                  1,500,000 shares contained in the Offering, but no later than
                  December 31, 2007, or any other date the parties herein agree
                  in writing.

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         5.2.     The Company may cancel this agreement upon

                  (i)      any misrepresentation or omission of or on behalf of
                           the Purchaser made to the Company in connection with
                           this Agreement;
                  (ii)     adjudication of bankruptcy, or filing of a petition
                           under any bankruptcy or debtor's relief law by or
                           against the Purchaser, or failure of the Purchaser to
                           generally pay its debts as they become due;
                  (iii)    termination of the Promissory Note given by the
                           Purchaser to the Company as of December 22, 2006;

6.       MISCELLANEOUS.

         6.1      GOVERNING LAW . This Agreement shall be governed by and
                  construed under the laws of the State of Nevada.

         6.2      SUCCESSORS AND ASSIGNS. Except as otherwise expressly provided
                  herein, the provisions hereof shall inure to the benefit of,
                  and are binding upon, the successors, assigns, heirs,
                  executors, and administrators of the parties hereto.

         6.3      ENTIRE AGREEMENT. This Agreement and the other documents
                  delivered pursuant hereto, constitute the full and entire
                  understanding and agreement among the parties with regard to
                  the subjects hereof and no party shall be liable or bound to
                  any other party in any manner by a representations,
                  warranties, covenants, or agreements except as specifically
                  set forth herein or therein. Nothing in this Agreement,
                  express or implied, is intended to confer upon any party,
                  other than the parties hereto and their respective successors
                  and assigns, any rights, remedies, obligations, or liabilities
                  under or by reason of this Agreement, except as expressly
                  provided herein.

         6.4      SEVERABILITY. In case any provision of this Agreement shall be
                  invalid, illegal, or unenforceable, it shall to the extent
                  practicable, be modified so as to make it valid, legal and
                  enforceable and to retain as nearly as practicable the intent
                  of the parties and the validity, legality, and enforceability
                  of the remaining provisions shall not in any way be affected
                  or impaired thereby.

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         6.5      AMENDMENT AND WAIVER. Except as otherwise provided herein, any
                  term of this Agreement may be amended, and the observance of
                  any term of this Agreement may be waived (either generally or
                  in a particular instance, either retroactively or
                  prospectively, and either for a specified period of time or
                  indefinitely), with the written consent of the Company and
                  Purchaser. Any amendment or waiver effected in accordance with
                  this Section shall be binding upon each future holder of any
                  security purchased under this Agreement (including securities
                  into which such securities have been converted) and the
                  Company.

         6.6      NOTICES. All notices and other communications required or
                  permitted hereunder shall be in writing and shall be effective
                  when delivered personally, or sent by telex or telecopier
                  (with receipt confirmed), provided that a copy is mailed by
                  registered mail, return receipt requested, or when received by
                  the addressee, if sent by Express Mail, Federal Express or
                  other express delivery service (receipt request) in each case
                  to the appropriate address set forth below.

If to the Company:                  PROTEO, INC.

                                    Birge Bargmann

                                    Proteo Biotech AG
                                    Am Kiel-Kanal 44
                                    D-24106 Kiel


If to a Purchaser:                  FID Esprit AG

                                    Axel Kutscher

                                    Rosengartenstr. 4
                                    CH-8608 Bubikon


         6.7      TITLES AND SUBTITLES. The titles of paragraphs and
                  subparagraphs of this Agreement are for convenience of
                  reference only and are not be not considered in construing
                  this Agreement.

         6.8      COUNTERPARTS. This Agreement may be executed in any number of
                  counterparts, each of which shall be deemed an original, but
                  all of which together shall constitute one instrument.

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

"COMPANY"
PROTEO, INC. a Nevada Corporation


By:  /S/ BIRGE BARGMANN
     ------------------------------
     CEO:  Birge Bargmann


"PURCHASER"
FIDEsprit AG


By:  /S/ AXEL J. KUTSCHER
     ------------------------------
     Managing Director: Axel J. Kutscher


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