UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 11-K

(Mark One)
x	ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2006
OR
o	TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                to

Commission File Number 000-19119

A. Full title of the plan and the address of the plan, if different from that of the issuer named below:

CEPHALON, INC. 401(k) PROFIT SHARING PLAN

B. Name of the issuer of the securities held pursuant to the plan and the address of its principal executive office:

CEPHALON, INC.

41 Moores Road

 Frazer, Pennsylvania 19355

(610) 344-0200

REQUIRED INFORMATION

       The Cephalon, Inc. 401(k) Profit Sharing Plan (the “Plan”) is subject to the Employee Retirement Income Security Act of 1974, as amended (“ERISA”) and the Plan’s financial statements and schedules have been prepared in accordance with the financial reporting requirements of ERISA. Such financial statements and schedules are included in this Report in lieu of the information required by Items 1-3 of Form 11-K.

Cephalon, Inc.

401(k) Profit Sharing Plan

Financial Statements as of and for the years ended

December 31, 2006 and 2005 and

Supplemental Schedule as of

December 31, 2006

Cephalon, Inc.

401(k) Profit Sharing Plan

Table of Contents

December 31, 2006 and 2005

	Page
Report of Independent Registered Public Accounting Firm	1
Financial Statements
Statements of Net Assets Available for Benefits at December 31, 2006 and 2005	2
Statements of Changes in Net Assets Available for Benefits for the years ended December 31, 2006 and 2005	3
Notes to Financial Statements	4
Supplemental Schedule *
Schedule H, Line 4i - Schedule of Assets (Held at End of Year)	9
Signatures	10
Exhibit Index	11

* Other supplemental schedules required by Section 2520.103-10 of the Department of Labor’s Rules and Regulations for Reporting and Disclosure under Employee Retirement Income Security Act of 1974, as amended (“ERISA”) have been omitted because they are not applicable.

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Participants and Administrator of

Cephalon, Inc. 401(k) Profit Sharing Plan:

In our opinion, the accompanying statements of net assets available for benefits and the related statements of changes in net assets available for benefits present fairly, in all material respects, the net assets available for benefits of the Cephalon, Inc. 401(k) Profit Sharing Plan (the “Plan”) at December 31, 2006 and 2005, and the changes in net assets available for benefits for the years then ended, 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) 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. The 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

Philadelphia, PA

June 18, 2007

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Cephalon, Inc.

401(k) Profit Sharing Plan

Statements of Net Assets Available for Benefits

December 31, 2006 and 2005

	2006		2005
Assets:
Investments, at fair value	$	131,571,554	$	93,014,728
Receivables:
Participant contributions	576,695		443,591
Employer contributions	1,001,721		791,518
Total receivables	1,578,416		1,235,109
Net assets available for benefits	$	133,149,970	$	94,249,837

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

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Cephalon, Inc.

401(k) Profit Sharing Plan

Statements of Changes in Net Assets Available for Benefits

For the Year Ended December 31, 2006 and 2005

	2006		2005
Additions:
Net appreciation in fair value of investments	$	7,852,062	$	4,690,904
Interest income	95,472		64,864
Dividend income	5,702,047		2,976,157
Total investment income	13,649,581		7,731,925
Participant contributions	17,956,800		12,844,228
Employer contributions	11,736,747		8,568,465
Total contributions	29,693,547		21,412,693
Total additions	43,343,128		29,144,618
Deductions:
Benefits paid to participants	4,429,123		4,738,448
Administrative fees	13,872		7,190
Total deductions	4,442,995		4,745,638
Net increase in net assets available for benefits	38,900,133		24,398,980
Net assets available for benefits:
Beginning of year	94,249,837		69,850,857
End of year	$	133,149,970	$	94,249,837

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

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Cephalon, Inc.

401(k) Profit Sharing Plan

Notes to Financial Statements

December 31, 2006 and 2005

1.Description of Plan

The following description of the Cephalon, Inc. 401(k) Profit Sharing Plan (the “Plan”) provides only general information. Participants in the Plan should refer to the Plan document for a more complete description of the Plan’s provisions.

General

Cephalon, Inc. and subsidiaries (collectively, “Cephalon” or the “Company”) established the Plan effective January 1, 1990.  The Plan is intended to be qualified under Section 401(a) of the U.S. Internal Revenue Code of 1986, as amended (the “IRC”), and is subject to the provisions of the ERISA.

Eligibility and Participation

The Plan is a defined contribution plan covering all full-time U.S. employees of the Company age 21 or older.  Eligible employees may enroll on the first day of employment.

Administration of the Plan

The Company is the Plan administrator. Additionally, the Company is the named fiduciary of the Plan, as well as the Plan sponsor, as defined by ERISA. The Company has delegated the responsibility for the review of investment performance and the selection of investment options for the Plan to an Investment Committee.  The Investment Committee operates under a written charter and consists of Company employees who are not compensated for services rendered.

Contributions

For the years ended December 31, 2006 and 2005, participants were permitted to contribute up to 20 percent of their eligible annual pre-tax compensation up to established federal limits on aggregate participant contributions.  As of January 1, 2007, participants are permitted to contribute any whole percentage of their eligible annual pre-tax compensation up to established federal limits on aggregate participant contributions.  In 2006 and 2005, the Company made a discretionary matching contribution equal to 100 percent of the employee elected salary deferral up to 6 percent of eligible compensation.

Participants in the Plan who are age 50 and older are permitted to make additional salary deferral contributions that will qualify as “catch-up” contributions under the Economic Growth and Tax Relief Reconciliation Act of 2001. These catch-up contributions are not eligible for employer matching contributions.

The Company also may contribute an annual discretionary profit sharing contribution.  No discretionary profit sharing contributions have been made to the Plan through December 31, 2006.  Profit sharing contributions will be made 100% in cash.

Company Stock

Participants may direct up to 20 percent of their contributions to purchase units of the Company Stock fund in the Plan.

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Participant Accounts

A participant may direct his or her contributions to various investment options offered by the Plan. As of December 31, 2006, the Plan offers 22 mutual funds, a Company stock fund and a brokerage account option as investment options for participants. Each participant’s account is credited with the participant’s elective contribution and allocations of (a) employer matching contribution, (b) investment earnings, net of investment expenses, (c) the Company’s profit sharing contribution, if applicable and (d) credited with administrative expenses, if applicable.  Allocations are based on participant compensation or account balances as defined.  The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested account.

As of November 1, 2006, due to a lack of participation, the brokerage account was frozen to any future contributions or transfers in and will be eliminated as an option altogether effective December 31, 2007.  Also, effective November 1, 2006, the T. Rowe Price Mid-Cap Value Fund – Advisor Class in the Plan was replaced with the T. Rowe Price Mid-Cap Value Fund – Retail Class, which has a lower expense ratio and overall lower fee structure.

Vesting and Forfeitures

Participants are immediately fully vested in their contributions plus actual earnings thereon and in all employer matching contributions made to the Plan on their behalf.  Discretionary profit sharing contributions, if any, will be fully vested (non-forfeitable).  As noted above, no discretionary profit sharing contributions have been made to date.

During 2006, forfeited funds that stemmed from excess employer matching contributions to participants during 2005 were returned to the Plan assets and were used to reduce 2006 employer matching contributions by $12,048 with $53 remaining in Plan assets at December 31, 2006.  At December 31, 2005, no forfeiture amounts remained in the Plan assets from prior years’ excess employer matching contributions.

Loans to Participants

Active participants may borrow a minimum of $1,000 and up to the lesser of $50,000 or 50 percent of their account balance. The interest rate for participant loans is the quarterly prime rate at the time of the inception of such loan plus one percent.  Participant loans are secured by the remaining balance in the participant’s account. As of December 31, 2006 and 2005, loans outstanding had interest rates ranging from 5.0% to 10.5% and 5.0% to 9.5%, respectively.  Loans are repaid via payroll deductions with a portion of such withholding designated as principal repayment and a portion as interest.  No loan repayment period may exceed five years, unless such loan was used to acquire the participant’s principal residence, in which case the Plan administrator may extend the period of repayment.

In the event of termination of employment, a participant’s loan must be repaid in full or it will be treated as a distribution.

Distributions to Participants

Upon termination of service, participants are eligible for a distribution of Plan benefits.  Benefits are paid in the form of a single lump-sum amount or may be rolled over to a qualified retirement plan.  Benefits representing Company Stock are paid in the form of Company Stock, if requested.

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The Plan allows a participant to elect to receive a distribution of his or her account balance if the participant experiences a total disability regardless of their employment status.  Participants may also make withdrawals for any reason after attaining age 59-1/2.

In the event of financial hardship (as defined in the Plan) and, if authorized by the Plan administrator, participants may withdraw money from their Plan accounts while they are still employed.

Administrative Expenses

Investment advisory fees for portfolio management are paid directly from fund earnings; they are included in the fund expense ratio.  Fees for specific services may be paid by employees.  During 2006 and 2005, $4,750 and $2,200 was paid by employees for loan processing and maintenance, respectively.  In addition, former employees who choose to keep their funds in the Plan paid a quarterly administrative fee as charged by Vanguard.  All other Plan expenses are paid by the Company.

2.     Summary of Significant Accounting Policies

Basis of Accounting

The accompanying financial statements of the Plan are prepared under the accrual basis of accounting in accordance with accounting principles generally accepted in the United States of America (“GAAP”).

Use of Estimates

The preparation of financial statements in accordance with GAAP 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. Actual results could differ from those estimates.

Valuation of Investments and Income Recognition

Investments are stated at fair value.  Shares of registered investment companies are valued at net asset value which represents the fair value of shares held by the Plan at year end.  The Company stock fund is valued at its year end unit closing price (comprised of year end market price of Company stock plus uninvested cash position).  Participant loans are valued at cost, which approximates fair value.

Purchases and sales of investments are recorded on the trade-date basis. Interest income is accrued when earned.  Dividend income is recorded on the ex-dividend date. Capital gain distributions are included in dividend income.

Payment of Benefits

Benefit payments to participants are recorded when paid.

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3.Investments

Investments that are five percent or more of the Plan’s net assets are as follows:

	December 31,
	2006		2005
Cephalon, Inc. Company Stock Fund	$	13,234,155	$	12,047,044
Vanguard Capital Opportunity Fund	9,860,068		7,048,048
Vanguard Windsor II Fund Investor Shares	8,936,756		6,178,744
Franklin Templeton Growth Fund, Class A	8,892,372		5,484,383
Vanguard PRIMECAP Fund	8,135,705		5,656,071
Vanguard Morgan Growth Fund Investor Shares	7,674,724		6,104,927
Vanguard 500 Index Fund Investor Shares	7,464,315		4,765,202
Royce Fund: Royce Premium Fund; Investment Class Shares*	6,931,668		4,691,018
Vanguard Prime Money Market Fund	6,864,313		5,541,406

*Did not represent five percent or more of the Plan’s net assets in 2005

During 2006 and 2005, the Plan’s investments (including gains and losses on investments bought and sold, as well as held during the year) appreciated in value as follows:

	2006		2005
Mutual funds	$	6,654,415	$	2,123,767
Cephalon, Inc. Company Stock Fund	1,197,647		2,567,137
Net appreciation	$	7,852,062	$	4,690,904

4.Plan Termination

Although it has not expressed any intent to do so, the Company reserves the right under the Plan to discontinue its contributions at any time and to change, amend or terminate the Plan, subject to the provisions of ERISA.

5.Tax Status

The Internal Revenue Service (“IRS”) has determined and informed the Plan sponsor by letter dated September 18, 1995, that the Plan is designed in accordance with applicable sections of the IRC. The Plan has been amended since its inception and received a favorable determination letter from the IRS on February 25, 2004 for the amendments.  The Plan has been amended since receiving the favorable determination letter; however, the Plan administrator believes that the Plan is currently designed and being operated in compliance with the applicable requirements of the IRC.  Therefore, the Plan administrator believes that the Plan was qualified and the related trust was tax-exempt as of the financial statement date.

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6.Related Party Transactions

Certain Plan investments are shares of mutual funds managed by The Vanguard Group.  The Vanguard Group is an affiliate of Vanguard Fiduciary Trust Company (“VFTC”), the trustee of the Plan.  Therefore, transactions in these investments qualify as party-in-interest transactions that are exempt from the prohibited transaction rules of ERISA.

The Plan invests in Company Stock; such transactions in Company Stock are exempt related party transactions. During the years ended December 31, 2006 and 2005, the Plan purchased shares of Company Stock having values of $1,536,858 and $989,688, respectively, and sold shares of Company Stock having values of $1,278,799 and $1,450,668, respectively, as directed by participants.  Loans to participants also qualify as exempt party-in-interest transactions.

7.Risks and Uncertainties

The Plan provides for various investment options in any combination of certain mutual funds and Company Stock. Investment securities, in general, are exposed to various risks, such as interest rate, market and credit risk. Due to the level of the risk associated with certain investment securities and the level of uncertainty related to changes in the value of investment securities, it is at least reasonably possible that changes in risks in the near term could materially affect participants’ account balances and the amounts reported in the statement of net assets available for benefits and the statement of changes in net assets available for benefits.

8.Reconciliation to Form 5500

The following is a reconciliation of net assets available for benefits per the financial statements to the Form 5500 for the years ended December 31:

	2006			2005
Net assets available for benefits per the financial statements	$	133,149,970		$	94,249,837
Less: Deemed distributions	(1,532		)	(1,532		)
Net assets available for benefits per the Form 5500	$	133,148,438		$	94,248,305

Deemed distributions are loans that are deemed uncollectible and treated as a payment of benefits.

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Cephalon, Inc.	Plan Number 001
Schedule H, Line 4i - Schedule of Assets (Held at End of Year)	E.I.N. 23-2484489
As of December 31, 2006

Identity of Issue	Description of Investment	Current Value
Franklin Templeton Growth Fund, Class A	Registered Investment Company	$	8,892,372
Royce Fund: Royce Premium Fund; Investment Class Shares	Registered Investment Company	6,931,668
Royce Total Return Fund-Financial Intermediary Shares	Registered Investment Company	4,236,040
T. Rowe Price Mid-Cap Value Fund	Registered Investment Company	3,069,749
*Vanguard 500 Index Fund Investor Shares	Registered Investment Company	7,464,315
*Vanguard Asset Allocation Fund	Registered Investment Company	2,126,644
*Vanguard Capital Opportunity Fund	Registered Investment Company	9,860,068
*Vanguard Equity Income Fund	Registered Investment Company	3,478,699
*Vanguard Explorer Fund	Registered Investment Company	5,996,219
*Vanguard Growth and Income Fund Investor Shares	Registered Investment Company	4,475,922
*Vanguard Intermediate-Term Treasury Fund Investor Shares	Registered Investment Company	3,833,134
*Vanguard LifeStrategy Conservative Growth Fund	Registered Investment Company	730,493
*Vanguard LifeStrategy Growth Fund	Registered Investment Company	4,480,362
*Vanguard LifeStrategy Income Fund	Registered Investment Company	769,122
*Vanguard LifeStrategy Moderate Growth Fund	Registered Investment Company	3,011,554
*Vanguard Morgan Growth Fund Investor Shares	Registered Investment Company	7,674,724
*Vanguard PRIMECAP Fund	Registered Investment Company	8,135,705
*Vanguard Prime Money Market Fund	Registered Investment Company	6,864,313
*Vanguard Strategic Equity Fund	Registered Investment Company	5,439,057
*Vanguard Total Bond Market Index Fund	Registered Investment Company	6,035,809
*Vanguard Wellington Fund Investor Shares	Registered Investment Company	3,990,331
*Vanguard Windsor II Fund Investor Shares	Registered Investment Company	8,936,756
*Vanguard Brokerage Option	Self-Directed Brokerage Fund Option	234,022
*Cephalon, Inc. Company Stock Fund	Company Stock Fund	13,234,155
*Participant Loan Fund	Loans maturing at various dates through October, 2036 with interest rates: 5.0% to 10.5%	1,670,321
		$	131,571,554

* Party-in-interest

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

	CEPHALON, INC. 401(k) PROFIT SHARING PLAN
Date: June 20, 2007	By:	/s/ CARL A. SAVINI
		Carl A. Savini
		Executive Vice President and Chief Administrative Officer
		Cephalon, Inc.
		(Plan Administrator)

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EXHIBIT INDEX

Exhibit Number	Exhibit
23.1	Consent of Independent Registered Public Accounting Firm.
99.1	Cephalon, Inc. 401(k) Profit Sharing Plan, Amended and Restated Effective November 1, 2004.
99.2	Amendment 2005-1 to the Cephalon, Inc. 401(k) Profit Sharing Plan.
99.3	Amendment 2005-2 to the Cephalon, Inc. 401(k) Profit Sharing Plan.
99.4	Amendment 2006-1 to the Cephalon, Inc. 401(k) Profit Sharing Plan.

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