Exhibit 10.4

 

***Text Omitted and Filed Separately

with the Securities and Exchange Commission.

Confidential Treatment Requested

Under 17 C.F.R. Sections 200.80(b)(4)

and 240.24b-2.

 

April 16, 2008

 

Merck & Co., Inc.
One Merck Drive
P.O. Box 100
Whitehouse Station, NJ  08889-0100

Attention:                 Office of the Secretary, WS3A-65

Chief Licensing Officer, WS2A-30

 

Re:                             License and Collaboration Agreement dated as of
June 22, 2005 (the “Collaboration Agreement”) between Merck & Co., Inc.
(“Merck”) and Metabasis Therapeutics, Inc. (“Metabasis”)

 

Ladies and Gentlemen:

 

This Letter (this “Letter”) confirms the understanding of Merck and Metabasis
regarding certain matters relating to the Collaboration Agreement and is
intended to be legally binding on both parties.  Capitalized terms used but not
otherwise defined in this Letter shall have the meanings provided in the
Collaboration Agreement.  The parties agree to extend the Research Term, which
is currently scheduled to terminate on June 21, 2008, on the terms and
conditions specified in this Letter.

 

The parties hereby acknowledge and agree that (a) as contemplated by […***…] of
the Collaboration Agreement, the Research Term is hereby extended for one
additional year from June 21, 2008 through June 21, 2009 (such extended time
period being referred to herein as the “Extension Period”), and
(b) notwithstanding anything to the contrary in […***…] of the Collaboration
Agreement, (i) unless otherwise agreed to by the parties in writing, Metabasis
shall dedicate […***…] FTEs to the Collaboration during the Extension Period,
which FTEs shall be funded by Merck in accordance with […***…] of the
Collaboration Agreement, and (ii) the provisions in […***…] of the Collaboration
Agreement regarding Aggregate FTEs and Additional Metabasis FTEs shall be
inapplicable during the Extension Period.  The parties further agree that,
pursuant to […***…] of the Collaboration Agreement, the JRC will amend the
Research Plan to reflect activities to be conducted during the Extension
Period.  It is the intent of the parties that for the duration of the Extension
Period, to the extent reasonably possible, […***…].

 

Except as amended by this Letter, the terms and conditions of the Collaboration
Agreement shall remain in full force and effect in all other respects, unless
further amended by written agreement in accordance with Section 13.3 of the
Collaboration Agreement.  On and after the effectiveness of this Letter, each
reference in the Collaboration Agreement to “this Agreement”, “hereunder”,
“hereof”, “herein” or words of like import referring to the Collaboration
Agreement shall mean and be a reference to the Collaboration Agreement as
amended by this Letter.  The parties hereby further agree

 

***Confidential Treatment Requested

 

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that the Dispute Resolution provisions of Article 12 of the Collaboration
Agreement and the terms and conditions set forth in Article 13 of the
Collaboration Agreement, including without limitation, the Governing Law
provisions of Section 13.2 and the Assignment and Change of Control provisions
of Section 13.6, shall apply to this Letter as if fully set forth herein.

 

This Letter may be executed (including, without limitation, by facsimile
signature) in two counterparts, each of which shall be deemed an original, but
both of which together shall constitute one and the same instrument.

 

If the foregoing is acceptable to you, please sign this Letter in the space
provided below and return it to me.

 

 

Sincerely,

 

 

 

METABASIS THERAPEUTICS, INC.

 

 

 

 

 

By:

     /s/ Paul Laikind, Ph.D.

 

Name:

 Paul Laikind, Ph.D.

 

Title:

   President and CEO

 

 

Agreed to and accepted as of the date first set forth above:

 

MERCK & CO., INC.

 

 

By:

      /s/ Mervyn Turner, PhD

 

 

 

Name:

Mervyn Turner, PhD

 

 

 

 

Title:

Senior Vice President, Worldwide

 

 

Licensing and Exmternal Research

 

 

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