Exhibit 10.3

FIRST AMENDMENT TO PURCHASE AND SALE

AGREEMENT AND JOINT ESCROW INSTRUCTIONS

(46 Galli Drive – Novato, CA)

THIS FIRST AMENDMENT TO PURCHASE AND SALE AGREEMENT (this “First Amendment”) is
effective as of February 23, 2006 by and between WIRRULLA NOVATO LLC, a
Washington limited liability company (“Seller”) and BIOMARIN PHARMACEUTICAL
INC., a Delaware corporation (“Buyer”).

R E C I T A L S :

A. Seller and Buyer are parties to that certain Purchase and Sale Agreement and
Joint Escrow Instructions effective as of January 24, 2006 (the “Original
Agreement”).

B. Seller and Buyer desire to amend the Original Agreement in accordance with
the terms of this First Amendment to amend the timing of the Contingency Period
and the Closing and to waive certain contingencies.

C. The term “Agreement” as used in this First Amendment shall mean and refer to
the Original Agreement as amended and modified by this First Amendment.

D. All capitalized terms not otherwise specifically defined in this First
Amendment shall have meanings ascribed to such terms in the Original Agreement.

NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth and for other good and valuable consideration, the receipt
and sufficiency of which is hereby acknowledged, the parties hereby agree as
follows:

1. Contingency Period. Section 2.2(a) of the Original Agreement is hereby
deleted in its entirety and replaced with the following:

(a) Buyer shall have until 5:00 p.m. PST on the date that is thirty (30) days
after the Effective Date in which to review and approve or disapprove (in
Buyer’s sole discretion) the matters described in Section 2.1(b)-(f) above (such
period being referred to herein as the “Contingency Period”), provided however,

(i) As of February 23, 2006, Buyer hereby satisfies and waives the contingencies
set forth in Section 2.1(a)-(c) and (f),

(ii) Buyer shall have until 5:00 p.m. Pacific on March 6, 2006 to satisfy the
contingency set forth in Section 2.1(d) and Buyer shall inform Seller and Escrow
Holder in writing by such date and time of the satisfaction of such contingency
(the “Board Approval Notice”), and

(iii) Buyer shall have until 5:00 p.m. Pacific on April 24, 2006 to satisfy the
contingency set forth in Section 2.1(e).

Satisfaction of the contingency set forth in Section 2.1(e) shall conclude the
Contingency Period and Buyer shall deliver its notice to proceed to Closing (the

 

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“Approval Notice”), if any, to Seller and the Escrow Holder no later than
April 24, 2006 and, upon delivery of such Approval Notice, the condition
described in Sections 2.1(e) shall be deemed either satisfied or waived by
Buyer. If Buyer does not send the Board Approval Notice or the Approval Notice,
this Agreement shall terminate, Buyer shall be entitled to the return of the
Deposit, the Escrow Holder shall return to the parties, respectively, the
documents they have deposited into Escrow and the parties shall have no further
liability to one another arising from this Agreement except for those provisions
which expressly survive termination of this Agreement.

2. The word “California” is hereby replaced by the word “Washington” in Seller’s
signature block in the Original Agreement

3. Effect of this First Amendment. Except as amended by this First Amendment,
the Original Agreement is hereby ratified and confirmed and all other terms of
the Original Agreement shall remain full force and effect, unaltered and
unchanged by this First Amendment. In the event of any conflict between the
provisions of this First Amendment and the provisions of the Original Agreement,
the provisions of this First Amendment shall prevail. Whether or not
specifically amended by the provisions of this First Amendment, all of the terms
and provisions of the Original Agreement are hereby amended to the extent
necessary to give effect to the purpose and intent of this First Amendment.

4. Counterparts. This First Amendment may be executed in any number of
counterparts, each of which shall be deemed an original, but all of which when
taken together will constitute one and the same instrument. The signature page
of any counterpart may be detached therefrom without impairing the legal effect
of the signature(s) thereon provided such signature page is attached to any
other counterpart identical thereto except having additional signature pages
executed by other parties to this First Amendment attached thereto. Executed
counterparts of this Agreement exchanged by facsimile transmission shall be
fully enforceable.

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

 

“SELLER”   WIRRULLA NOVATO LLC, a Washington limited liability company    

WIRRULLA USA, INC., a Washington corporation

Its Member

      /s/ Dharmesh Bhanabhai       By Dharmesh Bhanabhai, Secretary “BUYER”  

BIOMARIN PHARMACEUTICAL INC.,

a Delaware corporation

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

 

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