Exhibit 10.3

ASSIGNMENT AND ASSUMPTION AGREEMENT

     This ASSIGNMENT AND ASSUMPTION AGREEMENT (this “Agreement”) is entered into
as of January 27, 2006 (the “Effective Date”), by and between Raptor
Pharmaceutical Inc., a Delaware corporation (“Raptor”), and BioMarin
Pharmaceutical Inc., a Delaware corporation (“BioMarin”). BioMarin and Raptor
are each referred to herein individually as a “Party” and collectively as the
“Parties.”

RECITALS

     WHEREAS, BioMarin assigned certain technology and intellectual property to
Raptor under that certain “Asset Purchase Agreement” entered into on even date
herewith (the “Asset Purchase Agreement”); and

     WHEREAS, in connection with the Asset Purchase Agreement, Raptor desires to
have BioMarin transfer to Raptor, and BioMarin is willing to assign to Raptor,
the agreements attached hereto as Exhibits A-F (the “Assigned Contracts”) on the
terms and conditions set forth in this Agreement.

     NOW, THEREFORE, in consideration of the mutual promises contained herein
and intending to be legally bound, the Parties agree as follows:

     1. ASSIGNMENT. BioMarin does hereby unconditionally and irrevocably sell,
assign, transfer and convey to Raptor, its successors and assigns, all of
BioMarin’s legal, beneficial and other right, title and interest in and to the
Assigned Contracts free and clear of any Encumbrances. Capitalized terms not
otherwise defined herein shall have the meaning assigned to such terms in the
Asset Purchase Agreement.

     2. ASSUMPTION. Raptor shall assume all executory obligations under the
Assigned Contracts but only to the extent accrued after the Effective Date and
subject to the following. Raptor does not assume any indemnification obligations
or responsibilities based upon any activities occurring prior to the Effective
Date and does not assume any obligation or responsibility for any breach
occurring prior to the Effective Date. Raptor shall not assume, shall not take
subject to and shall not be liable for, any liabilities or obligations of any
kind or nature, whether absolute, contingent, accrued, known or unknown, of
BioMarin or any Affiliate of BioMarin regardless of when incurred, other than
obligations under the Assigned Contracts that accrued after, and are not based
upon activities occurring prior to, the Effective Date. Raptor does not assume
any liability for failure of BioMarin to obtain a required consent or approval
for the assignments. BioMarin shall remain liable for all payments that become
due or payable under the Assigned Contracts prior to the Effective Date.
Raptor’s assumption of liabilities as stated above shall control over any
statement to the contrary in the Asset Purchase Agreement. Raptor agrees and
acknowledges that each of the Assigned Contracts have expired and that the
rights transferred hereby are only the residual rights that survive termination.

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     3. AGREEMENT. The terms of Sections 7, 8.5 (except it shall apply with
respect to the Assigned Contracts in the same manner as it applies with respect
to the Transferred Technology), and 12 (excluding 12.11, 12.13, and 12.14) of
the Asset Purchase Agreement are incorporated herein by reference and shall
apply with respect to this Agreement in the same manner as they apply with
respect to the Asset Purchase Agreement. Raptor acknowledges and agrees that
BioMarin makes no representations about the enforceability, assignability or
worth of the Assigned Contracts other than to note that some or all of the
Assigned Contracts (i) may have expired or terminated and (ii) may not be
assignable without the written consent of the counterparties thereto, which
consent BioMarin has not obtained.

     4. FURTHER ASSURANCES. The parties hereto shall execute and deliver all
such other and further documents and perform all further acts that may be
reasonably necessary to effectuate the terms and provisions of this Agreement.

     5. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

     IN WITNESS WHEREOF, the parties have caused this Assignment and Assumption
Agreement to be executed as of January 27, 2006.

BIOMARIN PHARMACEUTICAL INC.

By:

Name: G. Eric Davis
Title: Vice President, Corporate Counsel

RAPTOR PHARMACEUTICAL INC.

By:

Name: Christopher Starr
Title: CEO

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