UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 11-K

ANNUAL REPORT
Pursuant to Section 15(d) of the
Securities Exchange Act of 1934

(Mark One)

þ		ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2007

o		TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                      to                     

Commission File Number: 1-3305
Employer Identification Number: 22-1109110
Plan Number: 001

MERCK & CO., INC. EMPLOYEE SAVINGS AND SECURITY PLAN

(Full title of the plan)

MERCK & CO., INC.

(Name of issuer of the securities held pursuant to the plan)

One Merck Drive
P.O. Box 100
Whitehouse Station, New Jersey 08889-0100

(Address of principal executive office)

 

 

Merck & Co., Inc.
Employee Savings and Security Plan

Employer Identification Number: 22-1109110
Plan Number: 001
Index

		Page
Report of Independent Registered Public Accounting Firm			1
Financial Statements:
Statements of Net Assets Available for Benefits as of December 31, 2007 and 2006			2
Statement of Changes in Net Assets Available for Benefits for the Year Ended December 31, 2007			3
Notes to Financial Statements			4 - 8
Supplemental Schedule*:
H — Line 4i — Schedule of Assets (Held at End of Year)			9
Signature			10
Exhibit Index			11
Exhibit 23 - Consent of Independent Registered Public Accounting Firm			12
EX-23: CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

*

Other schedules required by Section 2520.103-10 of the Department of Labor Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974 are omitted because they are not applicable.

Report of Independent Registered Public Accounting Firm

To the Participants and Administrator of
Merck & Co., Inc. Employee Savings and Security Plan

In our opinion, the accompanying statements of net assets available for benefits and the related statement of changes in net assets available for benefits present fairly, in all material respects, the net assets available for benefits of the Merck & Co., Inc. Employee Savings and Security Plan (the “Plan”) at December 31, 2007 and 2006, and the changes in net assets available for benefits for the year ended December 31, 2007 in conformity with accounting principles generally accepted in the United States of America. These financial statements are the responsibility of the Plan’s management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

Our audits were conducted for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental Schedule of Assets (Held at End of Year) as of December 31, 2007, is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. This supplemental schedule is the responsibility of the Plan’s management. The supplemental schedule has been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole.

/s/ PricewaterhouseCoopers LLP

New York, New York
June 26, 2008

Merck & Co., Inc.
Employee Savings and Security Plan

Statements of Net Assets Available for Benefits

		December 31,
		2007				2006
Assets
Investments, at fair value
Investment in the Master Trust		$	4,250,799,460			$	3,595,468,293
Participant loans			37,019,803				37,274,460
Total investments, at fair value			4,287,819,263				3,632,742,753
Receivables
Employer contribution			123,820				7,133,134
Participant contribution			288,778				17,026,291
Accrued dividends			6,759,853				6,942,180
Total receivables			7,172,451				31,101,605
Net assets available for benefits		$	4,294,991,714			$	3,663,844,358

The accompanying notes are an integral part of these financial statements.

Merck & Co., Inc.
Employee Savings and Security Plan

Statement of Changes in Net Assets Available for Benefits

		Year Ended
		December 31,
		2007
Additions to net assets attributed to
Investment income in the Master Trust
Net appreciation in fair value of investments		$	377,618,035
Interest and dividends			163,152,569
Net investment income			540,770,604
Contributions to the Plan
By participants			248,990,384
By employer			96,085,395
Total contributions			345,075,779
Asset transfer due to plan mergers			7,802,397
Transfers in			4,638,009
Total additions			898,286,789
Deductions from net assets attributed to
Benefits paid to participants			(264,899,682	)
Transfers out			(2,239,751	)
Total deductions			(267,139,433	)
Net increase			631,147,356
Net assets available for benefits
Beginning of year			3,663,844,358
End of year		$	4,294,991,714

The accompanying notes are an integral part of these financial statements.

Merck & Co., Inc.
Employee Savings and Security Plan

Notes to Financial Statements

1.		Description of Plan
		The following description of the Merck & Co., Inc. Employee Savings and Security Plan (the “Plan”) provides only general information. Participants should refer to the Plan document for a more complete description of the Plan’s provisions.
		General
		The Plan was designed to provide an easy, economical way for employees to become stockholders of Merck & Co., Inc. (the “Company” or “Merck”) as well as a systematic means of saving and investing for the future. Regular full-time, part-time, and temporary employees of the Company and of certain wholly-owned subsidiaries as defined by the Plan document who are not covered by a collective bargaining agreement are eligible to enroll in the Plan on or after the first day of the month following their date of hire.
		Participants direct the investment of their contributions into any fund investment option available under the Plan, including the Merck Common Stock Fund. During 2007, the Plan offered 18 mutual funds, a commingled fund, a separately managed fund and the Merck Common Stock Fund.
		The Plan is administered by a management committee appointed by the Company’s Chief Executive Officer or Compensation and Benefits Committee of its Board of Directors.
		The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974 (“ERISA”).
		Master Trust
		The assets of the Plan are maintained, for investment purposes only, on a commingled basis with the assets of the Merck & Co., Inc. Employee Stock Purchase & Savings Plan (the “Master Trust”). The Plans do not own specific Master Trust assets but rather maintain individual beneficial interests in such assets. The portion of fund assets allocable to each Plan is based upon the participants’ account balance within each Plan. Investment income for each fund is allocated to each Plan based on the relationship of each Plan’s beneficial interest in the fund to the total beneficial interest of all Plans in the fund.
		Contributions
		Participants may contribute from 2% up to 25% of their base pay. Employees earning less than $100,000 may contribute a maximum of 25% of base pay. Employees earning more than that amount are limited to maximum contributions of 15% of base pay. However, pre-tax contributions cannot exceed the statutory limit for pre-tax deferrals ($15,500 in 2007). In addition, the Company matches 75% of an employee’s contributions up to a maximum of 6% of such employee’s base pay per pay period. Company matching contributions are invested according to a participant’s elections.
		Age 50 and above — In addition, the Plan permits unmatched pre-tax “catch-up contributions” of up to $5,000 for 2007 by participants who are at least age 50 by year end.

Merck & Co., Inc.
Employee Savings and Security Plan

Notes to Financial Statements

		Participant Accounts
		Each participant’s account is credited with the participant’s contribution, the Company’s matching contribution and an allocation of Plan earnings. The allocation is based on participants’ account balances, as defined in the Plan document.
		Vesting
		Participants are immediately vested in their contributions, all Company matching contributions, plus actual earnings thereon.
		Participant Loans
		Participants may borrow from their account balances with interest charged at the prime rate plus 1%. Loan terms range from one to five years for a short term loan or up to thirty years for the purchase of a primary residence. The minimum loan is $500 and the maximum loan is the lesser of (i) $50,000 less the highest outstanding loan balance(s) during the one year period prior to the new loan application date, or (ii) 50% of the participant’s account balance less any current outstanding loan balance and defaulted loan amounts. Principal and interest is paid ratably through monthly payroll deductions.
		Payment of Benefits
		Salaried and hourly employees with status codes of terminated (which includes retired), long term disability or death, are eligible for a full distribution of their vested account balances. Employees or beneficiaries may elect to receive one lump sum payment or from one to ten annual installments. In-service distributions and hardship withdrawals are made throughout the year in accordance with applicable Plan provisions.
		Other Matters
		Transfers in and out during 2007 primarily relate to transfers between the Plan, and the Merck & Co., Inc. Employee Stock Purchase and Savings Plan and the Merck Puerto Rico Employee Savings and Security Plan for employees who changed their status during the year.
2.		Summary of Accounting Policies
		Basis of Accounting
		The accompanying financial statements are prepared on the accrual basis of accounting.
		Use of Estimates
		The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and changes therein, and disclosure of contingent assets and liabilities at the date of the financial statements. Management believes that these estimates are adequate. Actual results could differ from those estimates.
		Investment Valuation and Income Recognition
		Valuation of investments of the Plan represents the Plan’s allocable portion of the Master Trust. Quoted market prices are used to value investments. Shares of mutual funds are valued at the net asset value of shares held by the Master Trust at year end. For the commingled and separately

Merck & Co., Inc.
Employee Savings and Security Plan

Notes to Financial Statements

managed funds within the Master Trust, the investment units are based on the current market values of the underlying assets of the fund. Participant loans are valued at their outstanding balances.

Purchases and sales of securities are recorded on a trade-date basis. Dividend income is recorded on the ex-dividend date. Interest income is recorded as earned.

Employee and Company matching contributions are recorded in the period in which the Company makes the payroll deductions from the participants’ earnings.

Benefits are recorded when paid.

The Plan’s administrative expenses are paid by the Company.

The Plan provides for various investment options in investment securities. Investment securities, in general, are exposed to various risks and may decline in value for a number of reasons, including changes in prevailing interest rates and credit availability, increases in defaults, increases in voluntary prepayments for investments that are subject to prepayment risk under normal market conditions, widening of credit spreads and overall market volatility. Due to the level of risk associated with certain investment securities, it is reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants’ account balances and the amounts reported in the statement of net assets available for benefits.

In September 2006, the Financial Accounting Standards Board issued Statement No. 157, Fair Value Measurements (“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework for measuring fair value, and expands the disclosures on fair value measurements. FAS 157 is effective January 1, 2008 and the effect of adoption of FAS 157 on the Plan’s Statement of Net Assets Available for Benefits or Statement of Changes in Net Assets Available for Benefits is not expected to be material.

3.

Related-Party Transactions

Certain Plan investments are shares of mutual funds managed by Fidelity Management Trust Company (“Fidelity”). Fidelity is the trustee as defined by the Plan and, therefore, these transactions qualify as party-in-interest transactions. The total market value of investments in the mutual funds managed by Fidelity was $975,755,375 and $829,345,318 at December 31, 2007 and December 31, 2006, respectively.

Merck & Co., Inc. also is a party-in-interest to the Plan under the definition provided in Section 3(14) of ERISA. Therefore, Merck Common Stock Fund transactions qualify as party-in-interest transactions. The market value of investments in the Merck Common Stock Fund was

Merck & Co., Inc.
Employee Savings and Security Plan

Notes to Financial Statements

$1,040,263,889 and $801,341,057 at December 31, 2007 and December 31, 2006, respectively.

4.

Plan Termination

Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA. Upon termination of the Plan, each participant thereby affected would receive the entire value of his or her account as though he or she had retired as of the date of such termination.

5.

Tax Status

The Plan obtained a tax determination letter from the Internal Revenue Service dated August 20, 2003 indicating that it had been designed in accordance with applicable sections of the Internal Revenue Code (“IRC”). However, the Plan has been amended since the receipt of the determination letter. The Plan sponsor believes that the Plan is designed and currently operates in compliance with the IRC. Therefore, no provision for income taxes has been made.

6.

Master Trust

The Plan had an approximate 92% interest in the Master Trust at both December 31, 2007 and December 31, 2006, respectively. The net assets of the Master Trust are as follows:

		December 31,
		2007				2006
Mutual Funds		$	2,654,968,539			$	2,244,486,627
Commingled and Separately Managed Funds			764,390,505				749,397,294
Merck Common Stock Fund			1,189,336,367				922,164,315
Accrued interest and dividends			7,725,092				7,989,452
Total net assets		$	4,616,420,503			$	3,924,037,688

Total investment income of the Master Trust for the year ended December 31, 2007 is as follows:

Merck & Co., Inc.
Employee Savings and Security Plan

Notes to Financial Statements

		Year Ended
		December 31,
		2007
Investment income, net
Interest and dividends		$	177,508,876
Net appreciation in Mutual Funds			91,934,669
Net appreciation in Commingled and Separately Managed Funds			29,322,803
Net appreciation in Merck Common Stock Fund			302,172,886
Total investment income		$	600,939,234

7.

Plan Mergers

As a result of business acquisitions, the following transfers into the Plan were completed. In June 2007, the participants of the GlycoFi, Inc. 401(k) Profit Sharing Plan and net assets in the amount of $1,410,756 (which includes a loan balance of $28,289) were transferred into the Plan, pursuant to an acquisition agreement between the Plans. In November 2007, the participants of the Sirna Therapeutics, Inc. 401(k) Salary Reduction Plan and net assets in the amount of $6,391,641 (which includes a loan balance of $1,148) were transferred into the Plan, pursuant to an acquisition agreement between the Plans. The net assets transferred into the Plan are included in additions to net assets on the statement of changes in net assets.

EIN: 22-1109110
Plan No.: 001

				(c) Description of Investment Including
		(b) Identity of Issuer, Borrower,		Maturity date, Rate of Interest, Collateral,				(e) Current
(a)		Lessor or Similar Party		Par or Maturity Value		(d) Cost		Value
**		Master Trust		Investment in Master Trust		—		$	4,250,799,460
*		Participant Loans		Interest rates ranging from 5% to 12.5% and with maturities through 2038		—			37,019,803
				Total				$	4,287,819,263

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the undersigned plan administrator has duly caused this annual report to be signed on behalf of the Merck & Co., Inc. Employee Savings and Security Plan by the undersigned hereunto duly authorized.

June 26, 2008

EXHIBIT INDEX

Exhibit
Number		Document		Page
23		Consent of Independent Registered Public Accounting Firm		12