EX-10.6

Execution Copy

          LOCK-UP AGREEMENT, dated as November 26, 2007, by ARP BioMed, Ltd., a
limited liability company incorporated under the laws of the State of Israel,
with its business address for purposes hereof at c/o Mr. Yair Aloni, 12A Shbazi
Street, Neve Tzedek, Tel Aviv, Israel (“Seller”), for the benefit of GammaCan
International, Inc., a corporation incorporated under the laws of the State of
Delaware, with its business address for purposes hereof at 39 Jerusalem Street,
Kiryat Ono, 55423, Israel (the “Purchaser”). All capitalized terms used, but not
otherwise defined, herein shall have the respective definitions assigned thereto
in the Share Purchase Agreement (as hereinafter defined).

          In order to induce Purchaser to execute and deliver the Purchase
Agreement, the Seller hereby agrees as follows:

  1.1.

Lock-Up. Without limiting the provisions of applicable U.S. or other securities
laws, and in addition thereto:

      1.1.1.

From the date of the execution of the Share Purchase Agreement (the “Share
Purchase Agreement”) dated as of November 26, 2007 (the “Execution Date”) until
the date 18 months following the Execution Date, Seller will not offer, sell,
contract to sell, hypothecate, pledge or otherwise dispose of or enter into any
transaction which is designed to, or might reasonably be expected to, result in
the disposition (whether by actual disposition or effective economic disposition
due to cash settlement or otherwise) by the Seller or any Affiliate (as such
term is defined below) of the Seller or any person in privity with the Seller,
directly or indirectly, including the filing (or participation in the filing) of
a registration statement with the U.S. Securities and Exchange Commission in
respect of, or establish or increase a put equivalent position or liquidate or
decrease a call equivalent position within the meaning of Section 16 of the
Exchange Act with respect to, any of the Issued Shares, Warrants, Additional
Warrants or shares issuable upon exercise of the Warrants or the Additional
Warrants, or any security related to or derivative of any of the Purchaser’s
Securities, or any other shares of Common Stock of the Purchaser beneficially
owned, held or hereafter acquired by the Seller with respect to the Purchaser’s
Securities (collectively, the “Restricted Transactions” and the “Securities”,
respectively). Notwithstanding the above, the Seller may transfer the Securities
to its shareholders, and by its shareholders to their respective Permitted
Transferees, subject to the conditions and limitations set forth in the Share
Purchase Agreement who shall be subject to the terms of this Agreement.

      1.1.2.

From the date which is the date 18 months following the Execution Date, and
until the date which is the 24-month anniversary of the Execution Date, Seller
shall be permitted to effect a Restricted Transaction only with respect to one
sixth (1/6) of the Issued Shares, or the shares of the Purchaser issued as a
result of the exercise of the Warrant and the Additional Warrant, on an
accumulative basis, such

 

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that on the 24-month anniversary of the Execution Date all Securities shall be
released of any restriction under this Section 1.1.

      1.1.3.

For purposes hereof, beneficial ownership shall be calculated in accordance with
Section 13(d) of the Exchange Act, and the term “Affiliates” shall have the
meaning ascribed to it in the U.S. securities laws.

      1.1.4.

Without limiting any other provision of the Purchase Agreement, the Seller
acknowledges that its undertaking under this Section 1 is a material inducement
to the Purchaser to complete the transactions contemplated by the Purchase
Agreement, and that the Purchaser shall be entitled to specific performance of
the Seller’s undersigned’s obligations hereunder. In order to enforce this
covenant, the Purchaser shall impose stop-transfer instructions preventing its
Transfer Agent from effecting any actions in violation of this Agreement.

      1.1.5.

Notwithstanding the above, in the event of a “Change of Control”, as defined
below, the lock up obligation of the Seller and any of its transferees in
respect of the Securities shall expire ipso facto.

 

“Change of Control” shall mean the occurrence of the following: any person (as
the term “person” is used in Section 13(d)(3) or Section 14(d)(2) of the
Securities Exchange Act of 1934, as amended) other than the Company, any
subsidiary thereof, or any employee benefit plan of the Company or any
subsidiary thereof, becomes the beneficial owner of all of the voting power of
the then outstanding securities of Company entitled to vote generally in the
election of directors in exchange for (A) cash or (B) securities which may be
resold by the recipients thereof without restriction, provided, (i) that such
securities are issued by an issuer with a market capitalization of at least
US$7.5 billion immediately prior to the public announcement of such acquisition,
and (ii) that such issuer shall not require the continuation of the restrictions
on resale set forth herein as a condition of the transaction or transactions
resulting in such Change of Control.

2.

Miscellaneous.

    2.1.

This Agreement, the preamble and all exhibits and schedules hereto, and the
Purchase Agreement and the other exhibits thereto, constitute the full and
entire understanding and agreement between the Parties with regard to matters
set forth herein and therein, and supersede, nullify and terminate all prior
agreements between the Parties with regard to such subject matter.

    2.2.

No amendment of this Agreement shall be effective unless made in writing and
signed by or on behalf of each of the Parties.

    2.3.

Any notice required or permitted hereunder shall be in writing and shall be sent
by registered mail, personal delivery or confirmed facsimile to the relevant
Parties hereto at the respective addresses set forth below (as may be changed by
each of

 

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      the parties from time to time). Any notice shall operate and be deemed to
have been served, if personally delivered or sent by fax on the next following
business day, and if by registered mail, within three business days of dispatch.
Addresses of the parties for the purposes of this Agreement are as follows:    
    To the Seller: ARP BioMed Ltd.     c/o Mr. Yair Aloni     12A Shbazi Street,
Neve Tzedek, Tel Aviv     Telephone: +972-544234075     Facsimile:
+972-3-5165276       with a copy to (which shall not constitute service of
process on):     Yigal Arnon & Co.     1 Azrieli Center, Tel Aviv, 67021, Israel
    Fax: 972-3-6087713     Attn: Ms. Orly Tsioni, Adv.         To the Purchaser:
GammaCan International, Inc.     39 Jerusalem Street     Kiryat Ono, 55423,
Israel     Fax: 972-3-6356015     Attn: Chief Executive Officer       with a
copy to (which shall not constitute service of process on):     Ori Rosen & Co.,
Law Offices     1 Azrieli Center, Tel Aviv 67021, Israel     Fax: 972-3-6074701
    Attn: Mr. Ori Rosen, Adv.

  2.4.

Each Party shall bear all costs and expenses related to this Agreement and the
performance of its obligations hereunder, including all tax consequences.

    2.5.

This Agreement shall be governed by and construed in accordance with the laws of
the State of Israel. The Parties hereby irrevocably agree that the courts of Tel
Aviv shall have exclusive jurisdiction to settle any dispute that may arise out
of or in connection with this Agreement and agree to submit to the jurisdiction
of such courts.

    2.6.

In no event will a Party be liable to the other Party, whether for breach of
contract, in tort or otherwise, for incidental, indirect, special or
consequential damages, such as loss of revenues, profits or business
opportunity.

    2.7.

If any provision of this Agreement is held invalid or unenforceable, such
invalidity or unenforceability shall not affect the other provisions of this
Agreement, and, to that extent, the provisions of this Agreement are intended to
be and shall be deemed severable.

 

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      2.8.

This Agreement shall be binding upon and inure to the benefit of the Parties
hereto and their respective successors and assigns. No Party may assign its
respective obligations hereunder without the prior written consent of the other
Party. Any assignment in contravention of this provision shall be void.

    2.9.

This Agreement may be executed by the Parties hereto in separate counterparts,
each of which when so executed and delivered shall be an original, but all such
counterparts together shall constitute one and the same instrument.

 

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          IN WITNESS WHEREOF, this Agreement has been executed by Seller as of
the day and year first hereinabove written.

 

ARP BioMed, Ltd. (Seller)       By: Its:

 

 

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