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                                                                    Exhibit 4.3

SHARE EXCHANGE AGREEMENT


This Agreement is dated as at December 24, 2003 by and among :

1. MYMETICS CORPORATION, a company incorporated under the laws of Delaware
(United States of America), with registered office at c/o Cohen & Grigsby, 11,
Stanwix Street, Pittsburg PA 15222-1319 (United States of America), hereafter
represented by Mr. Christian ROCHET, President and Chief Executive Officer and
Mr. Ernst LUBKE, Chief Financial Officer (hereafter called "Mymetics")

2. [Details of Investor] (hereafter called "the Investor")

being hereafter collectively referred to as the "Parties to the present
agreement" and any of them also referred to as a "Party".


WHEREAS the company 6543 LUXEMBOURG S.A. (being hereafter referred to as "the
Company") is a "societe anonyme" incorporated under the laws of Luxembourg on
March 28, 2001, inscribed at the Trade Register of Luxembourg under number B 81
628 and having its registered office at L-1325 Luxembourg, 3, rue de la
Chapelle.

WHEREAS the Company has two classes of shares, being Class A Shares, composed of
15,865 ordinary shares and Class B Shares, composed of 15,372 exchangeable
preferential non voting shares.

WHEREAS the holders of Class B Shares had the right to proceed to an exchange of
their Class B Shares against common shares of Mymetics and to date, have
effectively exchanged each of their Class B Shares against common shares of
Mymetics.

WHEREAS the Investor intends to subscribe to 800 new Class B Shares of the
Company at a total subscription price of E 83,200 and wants to benefit from the
same right of exchange of such shares against common shares of Mymetics as had
the former Class B shareholders of the Company.

WHEREAS the Investor wants furthermore an irrevocable option to subscribe latest
on June 30, 2004 to an additional number of 1,000,000 shares of Mymetics at a
total exercise price of US$ 100,000.-,

WHEREAS Mymetics is willing to grant such rights to the Investor.

NOW, THEREFORE, in consideration of the mutual promises and agreements set forth
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree as follows :



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1. Agreement

1.1. Exchange of shares:

Mymetics hereby agrees to proceed, at the request of the Investor, to an
exchange of each and all, but not less than all, of the new Class B Shares of
the Company which will be held by the Investor subsequent to an increase of
subscribed capital of the Company effected before January 31, 2004 (hereafter
"the Shares") against shares of common stock of Mymetics, par value $0.01.

For each share of Class B of the Company the Investor shall receive 1,250 (and
not more) shares of common stock of Mymetics.

The Investor undertakes that at the time of such request, he will be the sole
legal and beneficial owner of record with good, full and marketable title to the
Shares to be transferred to Mymetics by way of exchange and upon consummation of
such exchange, Mymetics will acquire from the Investor good and marketable title
to such Shares, free and clear of all liens, pledges, options, restrictions and
other encumbrances.

The request for exchange can be made at any time and shall be sent to Mymetics
by way of registered letter in the form annexed hereto with a copy to the
Company. Upon receipt of such letter, Mymetics will require the Company to
reflect in its share register the transfer of the Class B Shares to Mymetics and
will furthermore have Mymetics' transfer agent issue to the Investor a new stock
certificate representing the shares of Mymetics Common Stock held by the
Investor pursuant to the exchange.

As from the date of the exchange, all rights to the Class B Shares of the
Company, including all dividend rights, shall pass from the Investor to
Mymetics.

1.2. Warrant:

Mymetics furthermore agrees to grant to the Investor an irrevocable option to
subscribe to an additional number of 1,000,000 shares of Mymetics at a total
exercise price of US$ 100,000.

The Investor must exercise such right before June 30, 2004.

In order to entitle the Investor to exercise such right under the before stated
conditions, Mymetics undertakes to issue within a reasonable delay as from today
warrants allowing such subscription of 1,000,000 shares of common stock of
Mymetics, par value $0.01 per share by the Investor.


2. Further Assurances

Each party hereto shall do and perform or cause to be done and performed all
such further acts and things and shall execute and deliver all such other
agreements, certificates, instruments and documents as any other party hereto
may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.




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3. Notices

All notices, requests, claims, demands, reports and other communications
hereunder shall be in writing and shall be given or made (and shall be deemed to
have been duly given or made upon receipt) by delivery in person, by courier
service, by telecopy or e-mail, or by registered mail to the respective parties
at the following addresses (or at such other address for a party as shall be
specified in a notice given in writing to the Company) :

(a) if to MYMETICS :

MYMETICS CORPORATION
European Executive Office
65, route du Boiron
1260 Nyon
Switzerland
Tel : 011 41 22 363 13 10
Fax : 011 41 22 363 13 11

(b) if to the Investor :

[Investor's details]

(c) if to the Company :

6543 LUXEMBOURG S.A.
3, rue de la Chapelle
L-1325 LUXEMBOURG

Tel : 011 352 45 80 45 - 42
Fax : 011 352 45 45 89


4. Amendment and modification

No change or modification of this agreement shall be valid, binding or
enforceable unless the same shall be in writing and signed by all the Parties to
the present agreement.


5.Severability - Language

If any provision of this Agreement or the application thereof to any party or
circumstance shall be held invalid or unenforceable to any extent, the remainder
of this Agreement and the application of such provisions to the other parties or
circumstances shall not be affected thereby and shall be enforced to the
greatest extent permitted by applicable law.

In the event of any discrepancies or contradictions between this Agreement and
the Articles, this Agreement shall prevail to the extent permitted by law.


6. Governing Law

This Agreement shall be governed by and construed in accordance with the laws of
the Grand Duchy of Luxembourg (the "Agreed Jurisdiction").



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7. Resolution of disputes

In the event of disagreement between the Parties to the present agreement or
between the Parties to the present agreement and the Company, every effort will
be made at all levels in order to have it resolved. If necessary, an
extraordinary general meeting of the Shareholders of the Company will be held.

In the event that the disagreement is not resolved after a period of 30 days,
any dispute, controversy or claim arising out of, relating to or in connection
with this Agreement (hereafter "Dispute") shall be submitted to and finally
settled by arbitration under and in accordance with the Rules of Conciliation
and Arbitration of the International Chamber of Commerce (the "Rules"). A party
wishing to submit a dispute to arbitration shall give written notice to such
effect to the other party/parties hereto. The parties shall have 30 calendar
days after the giving of such notice to designate the arbitrators for the
dispute. The party having started the arbitration procedure shall designate one
arbitrator and the other party/parties hereto shall designate one arbitrator.
The two designated arbitrators shall in turn choose a third arbitrator, who
shall also be the chairman of the panel. If one of the two parties appoints an
arbitrator but the other party fails to appoint its arbitrator within the 30-day
period specified above, then the appointment of such second arbitrator shall be
made by the President of the "Tribunal d'arrondissement de et a Luxembourg" upon
the request of the other party ; and if the appointed arbitrators shall fail to
appoint the third arbitrator within the 30 calendar days after the date of
appointment of the most recently appointed arbitrator, the third arbitrator
shall be appointed by the President of the "Tribunal d'arrondissement de et a
Luxembourg" upon the request of either party. The site of the arbitration shall
be Luxembourg, and the language to be used in the arbitration proceedings shall
be the English language. The decision of the arbitrators shall be rendered
within 90 calendar days from the appointment of the last arbitrator, and shall
be final and binding upon all parties.


8. Miscellaneous

8.1. Section headings are for convenience of reference only and shall not be
used to construe the meaning of any provision of this Agreement.

8.2. This Agreement may be executed in any number of counterparts, each of which
shall be an original, and all of which shall together constitute one agreement.

8.3 This Agreement is for the sole benefit of the parties hereto and their
permitted assigns and nothing herein, express or implied, is intended to or
shall confer upon any other person or entity any legal or equitable right,
benefit or remedy of any nature whatsoever under or by reason of this Agreement.

8. 4 This Agreement shall become effective as of the date of its signature.



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In witness whereof this Agreement was signed and executed by the Parties hereto
in Nyon on the date first written above.


MYMETICS CORP.                                       Investor

Christian Rochet                                     [Investor's name]
President and
Chief Executive Officer



Ernst Lubke
Chief Financial Officer



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Form of request for exchange




MYMETICS CORPORATION
European Executive Office
65, route du Boiron
1260 Nyon
Switzerland


Re: Share Exchange Agreement dated December 24, 2003


Dear Sirs,

I refer to the Share Exchange Agreement signed with your company on December 24,
2003.

I do inform you hereby that I want to exercise my right of exchange of my 800
Class B shares of the Luxembourg company 6543 LUXEMBOURG S.A., having its
registered office at L-1325 Luxembourg, 3, rue de la Chapelle against shares of
common stock of your company.

As a consequence, please instruct the company 6543 LUXEMBOURG S.A. to reflect in
its share register the transfer of my Class B Shares to Mymetics and furthermore
have your transfer agent issue to me a new stock certificate representing the
1,000,000 shares of Mymetics Common Stock held by me pursuant to this exchange.

Yours sincerely,







[Investor]









Copy: 6543 LUXEMBOURG S.A.



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