Exhibit 10.3

Guarantee and Joinder Agreement

GUARANTEE AND JOINDER AGREEMENT dated as of November 3, 2009 by Merck & Co.,
Inc. (formerly Schering-Plough Corporation), a New Jersey corporation (with its
successors, the “Guarantor”) for the benefit of the Guaranteed Parties named
below.

WHEREAS, the Guarantor is the Parent of Merck Sharp & Dohme Corp. (formerly
Merck & Co., Inc.), a New Jersey Corporation (with its successors, the
“Company”); and

WHEREAS, the Company, the LENDERS party thereto (the “Lenders”) and CITICORP
USA, INC., as Administrative Agent (the “Administrative Agent” and, together
with the Lenders, the “Guaranteed Parties”) are parties to the Amended and
Restated Credit Agreement dated as of April 12, 2006 (as amended on or prior to
the date hereof, including by Amendment No. 1 thereto dated April 20, 2009, the
“Credit Agreement”).

WHEREAS, the Guarantor is willing to enter into this Guarantee and Joinder
Agreement; and

WHEREAS, terms defined in the Credit Agreement and not otherwise defined herein
have, as used herein, the respective meanings provided for therein;

NOW, THEREFORE, in consideration of the foregoing and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
Guarantor agrees as follows:

1. The Guarantee. The Guarantor hereby unconditionally guarantees to each
Guaranteed Party the full and punctual payment when due (whether at stated
maturity, upon acceleration or otherwise) of the principal of and interest on
any and all Advances made to and Reimbursement Obligations of the Company,
obligations of the Company pursuant to Article 10 of the Credit Agreement, and
all other amounts whatsoever from time to time owing to the Guaranteed Parties
or any of them by the Company under the Credit Agreement and the other Loan
Documents, in each case strictly in accordance with the terms thereof (the
“Guaranteed Obligations”). Upon failure by the Company to pay any Guaranteed
Obligation punctually when due, the Guarantor shall forthwith on demand pay the
amount not so paid at the place and in the manner specified in the instrument
evidencing such Guaranteed Obligation; provided that, in the case of any
extension of time of payment or renewal of any of the Guaranteed Obligations,
the same will be punctually paid in full when due (whether at extended maturity,
by acceleration or otherwise) in accordance with the terms of such extension or
renewal.

2. Guarantee Unconditional. The obligations of the Guarantor hereunder shall be
unconditional and absolute and, without limiting the generality of the
foregoing, shall not be released, discharged or otherwise affected by:

(a) any extension, renewal, settlement, compromise, waiver or release in respect
of any obligation of the Company or any other Person under any Loan Document, by
operation of law or otherwise;

(b) any modification or amendment of or supplement to any Loan Document;

(c) any release, impairment, non-perfection or invalidity of any direct or
indirect security for any obligation of the Company or any other Person under
any Loan Document;

 

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(d) any change in the corporate existence, structure or ownership of the Company
or any other Person, or any insolvency, bankruptcy, reorganization or other
similar proceeding affecting the Company or any other Person or any of their
assets or any resulting release or discharge of any obligation of the Company or
any other Person under any Loan Document;

(e) the existence of any claim, set-off or other rights that the Guarantor may
have at any time against the Company or any other Person, whether in connection
with the Loan Documents or with any unrelated transactions; provided that
nothing herein shall prevent the assertion of any such claim by separate suit or
compulsory counterclaim;

(f) any invalidity or unenforceability relating to or against the Company or any
other Person for any reason of any Loan Document or any provision of applicable
law or regulation purporting to prohibit the payment of any Guaranteed
Obligation by the Company or any other Person; or

(g) any other act or omission to act or delay of any kind by the Company, or any
other Person or any other circumstance whatsoever which might, but for the
provisions of this paragraph, constitute a legal or equitable discharge of or
defense to the Guarantor’s obligations hereunder.

3. Limit of Liability. If the Guarantor (other than, for the avoidance of doubt,
the Company in its capacity as a Guarantor) is a subsidiary of Parent (such
Guarantor a “Subsidiary Guarantor”), the obligation of such Guarantor under this
Guarantee shall be limited to an aggregate amount equal to the largest amount
that would not render its obligations hereunder subject to avoidance under
Section 548 of the United States Bankruptcy Code or any comparable provision of
any other applicable law.

4. Release of Guarantee.

(a) The Guarantor’s obligations hereunder shall, subject to clause (c) below,
remain in full force and effect until all Guaranteed Obligations shall have been
paid in full (other than contingent indemnification obligations as to which no
claims have been asserted) and no Lender shall have any Commitment under, and no
Letter of Credit shall remain outstanding under, the Credit Agreement.

(b) If at any time any payment of any Guaranteed Obligation is rescinded or must
be otherwise restored or returned upon the insolvency, bankruptcy or
reorganization of the Company or otherwise, the Guarantor’s obligations
hereunder with respect to such payment shall be reinstated as though such
payment had been due but not made at such time.

(c) If it shall come to pass that any Subsidiary Guarantor is a guarantor
neither with respect to any other Credit Facility nor with respect to the Senior
Notes, or any Subsidiary Guarantor shall cease to be a Subsidiary of the Parent,
or all the assets of a Subsidiary Guarantor are sold to a Person other than the
Parent or any of its Subsidiaries, in each case, in a transaction not otherwise
prohibited by the Credit Agreement (any such sale, a “Sale of Guarantor”), such
Subsidiary Guarantor shall be automatically released from its Guarantee
hereunder, and the Administrative Agent shall, at the Company’s expense, execute
and deliver such documents as the Company may reasonably request to evidence
such release. Such release shall not require the consent of any Lender or the
Administrative Agent and the Administrative Agent shall be fully protected in
relying on a certificate of the Company or the Parent as to whether the
foregoing conditions are satisfied.

 

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5. Waiver by the Guarantor. The Guarantor irrevocably waives acceptance hereof,
presentment, demand, protest and any notice not provided for herein, as well as
any requirement that at any time any action be taken by any person or entity
against any other guarantor, the Company or any other person or entity.

6. Subrogation. Upon making full payment with respect to any Guaranteed
Obligation hereunder, the Guarantor shall be subrogated to the rights of the
payee against the Company with respect to such payment; provided that the
Guarantor shall not enforce any payment by way of subrogation against the
Company unless all Guaranteed Obligations shall have been paid in full (other
than contingent indemnification obligations as to which no claims have been
asserted) and no Lender shall have any Commitment under, and no Letter of Credit
shall remain outstanding under, the Credit Agreement.

7. Stay of Acceleration. If acceleration of the time for payment of any
Guaranteed Obligation is stayed upon the insolvency, bankruptcy or
reorganization of the Company, all such Guaranteed Obligations otherwise subject
to acceleration under the terms of the Credit Agreement shall nonetheless be
payable by the Guarantor hereunder forthwith on demand by the Administrative
Agent.

8. Continuing Guarantee. This Guarantee is a continuing guarantee, shall be
binding on the Guarantor and its successors and assigns, and shall be
enforceable by the Guaranteed Parties. If all or part of the Guaranteed Parties’
interest in any Guaranteed Obligation is assigned or otherwise transferred, the
transferor’s rights under this Guarantee, to the extent applicable to the
obligation so transferred, shall automatically be transferred with such
obligation.

9. Party to Credit Agreement. Upon delivering this Guarantee and Joinder
Agreement to the Administrative Agent, the Guarantor will become a party to the
Credit Agreement, and the Guarantor will thereafter have all the rights and
obligations of a “Guarantor”, a “Credit Party” and “the Parent” thereunder and
be bound by all the provisions thereof as fully as if the Guarantor were one of
the original parties thereto.

10. Representations and Warranties. Each of the representations and warranties
set forth in Article 4 of the Credit Agreement that relate to the Guarantor is
true as applied to the Guarantor as of the date hereof.

11. No Waiver. No failure to exercise or delay in exercising any right, power or
privilege under this Guarantee and Joinder Agreement or any other Loan Document
shall operate as a waiver thereof, nor shall any single or partial exercise of
any right, power or privilege under this Guarantee and Joinder Agreement or any
other Loan Document preclude any other or further exercise thereof or the
exercise of any other right, power or privilege. The remedies provided herein
are cumulative and not exclusive of any remedies provided by law.

12. Amendments and Waivers. Any provision of this Guarantee may be amended or
waived if, but only if, such amendment or waiver is in writing and is signed by
Majority Lenders and the Guarantor; provided that no such amendment or waiver
shall, without the written consent of all Lenders, (x) release the Guarantor
from, or limit its liability with respect to, its obligations hereunder (other
than as provided for in Section 4 hereof) or (y) modify this Section 12.

 

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13. Successors and Assigns. This Guarantee shall be binding upon the Guarantor
and its successors and assigns, for the benefit of the Guaranteed Parties and
their successors and assigns, except that the Guarantor may not transfer or
assign any or all of its rights or obligations hereunder without the prior
written consent of all Lenders.

14. Miscellaneous. The Guarantor hereby agrees that this Guarantee and Joinder
Agreement shall be governed by, and construed in accordance with, the law of the
State of New York. The Guarantor hereby submits to the nonexclusive jurisdiction
of any New York State court or Federal court of the United States of America, in
each case sitting in New York County, and any appellate court from any thereof,
in any action or proceeding arising out of or relating to this Guarantee and
Joinder Agreement or any of the other Loan Documents, or for recognition or
enforcement of any judgment, and agrees that all claims in respect of any such
action or proceeding may be heard and determined in any such New York State
court or, to the extent permitted by law, in such Federal court. The Guarantor
irrevocably waives, to the fullest extent permitted by law, any objection which
it may now or hereafter have to the laying of venue of any action or proceeding
arising out of or relating to this Guarantee and Joinder Agreement or any of the
other Loan Documents in any New York State or Federal court and the defense of
an inconvenient forum to the maintenance of such action or proceeding in any
such court. The Guarantor further irrevocably agrees that any and all legal
process in connection with any such action or proceeding in any such court may
be effected by mailing a copy thereof by registered or certified mail, postage
prepaid, to it at the address set forth in Section 9.02(a) of the Credit
Agreement, such service being hereby acknowledged by such Credit Party to be
effective and binding service.

15. WAIVER OF JURY TRIAL. THE GUARANTOR IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY
JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT
OR OTHERWISE) ARISING OUT OF OR RELATING TO THIS GUARANTEE AND JOINDER AGREEMENT
OR ANY OF THE OTHER LOAN DOCUMENTS.

IN WITNESS WHEREOF, the Guarantor has caused this Guarantee and Joinder
Agreement to be duly executed by its authorized officer as of the day and year
first above written.

 

MERCK & CO., INC. By:  

/S/    PETER N. KELLOGG        

Name:   Peter N. Kellogg Title:   Executive Vice President and Chief Financial
Officer

 

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