8-K

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): April 7, 2004

GENZYME CORPORATION
(Exact name of registrant as specified in its charter)

Massachusetts
(State or other jurisdiction
of incorporation or organization) 0-14680
(Commission
File Number) 06-1047163
(IRS Employer
Identification Number)

500 Kendall Street, Cambridge, Massachusetts 02142
(Address of Principal Executive Offices)    (Zip Code)

Registrant's telephone number, including area code: (617) 252-7500

Item 5. Other Events.

        As reported on our current report on Form 8-K dated February 26, 2004 (filed February 27, 2004), on February 26, 2004 we and two of our wholly-owned subsidiaries, GLBC Corp. and GLBC LLC, entered into an Agreement and Plan of Merger with ILEX Oncology, Inc., or ILEX, pursuant to which the parties plan to effect a business combination through an initial merger of GLBC Corp. with and into ILEX, and a subsequent merger of ILEX with and into GLBC LLC. As a result of this transaction, ILEX is expected to become a wholly-owned subsidiary of Genzyme. Consummation of the merger is subject to the satisfaction of customary closing conditions. If all these conditions are not satisfied or waived, the merger will not be completed.

        We are filing this report to include the unaudited, pro forma combined financial information which describes the pro forma effect of our proposed transaction with ILEX on our statements of operations for the year ended December 31, 2003, as if the transaction had occurred on January 1, 2003, and our balance sheet as of December 31, 2003, as if the transaction had occurred on that date.

Item 7. Financial Statements, Pro Forma Financial Information And Exhibits.

(c)

Exhibits:

99.1 Unaudited, pro forma combined financial information which describes the pro forma effect of our proposed transaction with ILEX on our statements of operations for the year ended December 31, 2003, as if the transaction had occurred on January 1, 2003, and our balance sheet as of December 31, 2003, as if the transaction had occurred on that date. Filed herewith.

SIGNATURE

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

GENZYME CORPORATION
By:	/s/  MICHAEL S. WYZGA Michael S. Wyzga Executive Vice President, Finance, Chief Financial Officer, and Chief Accounting Officer

DATE: April 7, 2004

EXHIBIT INDEX

EXHIBIT NO.	DESCRIPTION
99.1	Unaudited, pro forma combined financial information which describes the pro forma effect of our proposed transaction with ILEX on our statements of operations for the year ended December 31, 2003, as if the transaction had occurred on January 1, 2003, and our balance sheet as of December 31, 2003, as if the transaction had occurred on that date. Filed herewith.

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Item 5. Other Events.
Item 7. Financial Statements, Pro Forma Financial Information And Exhibits.

SIGNATURE
EXHIBIT INDEX

EX-99.1

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UNAUDITED, PRO FORMA COMBINED FINANCIAL INFORMATION

        The following unaudited, pro forma combined financial information describes the pro forma effect of Genzyme's proposed transaction with ILEX Oncology, Inc., or ILEX, on its statements of operations for the year ended December 31, 2003, as if the transaction had occurred on January 1, 2003, and its balance sheet as of December 31, 2003, as if the transaction had occurred on this date. Certain historical financial information of ILEX has been reclassified to conform with the presentation of Genzyme's historical financial statements.

        This pro forma combined financial information is for informational purposes only. It does not purport to indicate the results that would have actually been obtained had the transaction been completed on the assumed date or for the periods presented, or which may be obtained in the future. To produce the pro forma financial information, Genzyme allocated the purchase price using its best estimates. The unaudited, pro forma combined financial statements should be read in conjunction with the historical consolidated financial statements, including notes thereto, of both Genzyme and ILEX. The historical consolidated financial statements of Genzyme are included in Exhibit 13.1 to Genzyme's annual report on Form 10-K for the year ended December 31, 2003, filed with the Securities and Exchange Commission, or SEC, on March 15, 2004. The historical consolidated financial statements of ILEX are included in pages F-1 through F-31 of ILEX's anual report on Form 10-K for the year ended December 31, 2003, filed with the SEC on March 12, 2004.

        The merger agreement between Genzyme and ILEX provides that a Genzyme subsidiary would be merged with and into ILEX, which would then be merged into another wholly-owned subsidiary of Genzyme. In the transaction, each outstanding share of ILEX common stock would be converted into the right to receive a fraction of a share of Genzyme common stock. We refer to this fraction as the "exchange ratio," and it would be calculated by dividing $26.00 by the average per share closing price of Genzyme common stock as reported by the NASDAQ National Market over the 20 trading days ending on the fifth trading day prior to the closing of the transaction, except that if the average closing price is greater than $59.88, the exchange ratio would be 0.4342, and if the average closing price is less than $46.58, the exchange ratio would be 0.5582. Cash would be paid for any fractional shares that result from conversion of ILEX common stock to Genzyme common stock. Additionally, each option to purchase shares of ILEX common stock outstanding immediately before the effective date of the merger would be assumed by Genzyme after the merger and would be exchanged for a fully vested option to purchase shares of Genzyme common stock. The transaction would be accounted for as a purchase and is expected to qualify as a tax-free reorganization.

        Genzyme has prepared the unaudited, pro forma combined financial information using the purchase method of accounting for the transaction. Genzyme expects to have reorganization and restructuring expenses as well as potential operating efficiencies as a result of the transaction. The unaudited, pro forma combined financial statements and related notes do not reflect these potential expenses and efficiencies.

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GENZYME CORPORATION
UNAUDITED, PRO FORMA COMBINED STATEMENTS OF OPERATIONS
For the Year Ended December 31, 2003
(Amounts in thousands)

				Historical Genzyme Corporation			Historical ILEX Oncology, Inc.			Pro Forma Adjustments			Footnote Reference	Pro Forma Genzyme Corporation
Revenues:
	Net product sales			$	1,563,509		$	—		$	—			$	1,563,509
	Product profit and royalty				—			23,315			—				23,315
	Net service sales				130,984			—			—				130,984
	Outlicensing revenue				—			2,773			—				2,773
	Revenues from research and development contracts:
		Related parties			1,836			—			—				1,836
		Other			17,542			8,701			—				26,243
			Total revenues		1,713,871			34,789			—				1,748,660
Operating costs and expenses:
	Cost of products sold				399,961			—			—				399,961
	Cost of services sold				75,683			—			—				75,683
	Selling, general and administrative				519,977			14,713			—				534,690
	Research and development (including research and development related to contracts)				335,256			60,693			—				395,949
	Amortization of intangibles				80,257			4,945			19,113		[A1]		104,315
	Purchase of in-process research and development				158,000			—			—				158,000
	Charge for impaired goodwill				102,792			—			—				102,792
	Charge for impaired assets				10,894			213			—				11,107
	Settlement charge				—			16,500			—				16,500
			Total operating costs and expenses		1,682,820			97,064			19,113				1,798,997
Operating income (loss)					31,051			(62,275	)		(19,113	)			(50,337	)
Other income (expenses):
	Equity in loss of equity method investments				(16,743	)		—			—				(16,743	)
	Loss on investments in equity securities				(1,201	)		—			—				(1,201	)
	Minority interest				2,232			—			—				2,232
	Loss on sale of product line				(27,658	)		—			—				(27,658	)
	Other				959			18			—				977
	Investment income				43,015			4,304			—				47,319
	Interest expense				(26,600	)		(4,137	)		—				(30,737	)
			Total other income (expenses)		(25,996	)		185			—				(25,811	)
Income (loss) before income taxes					5,055			(62,090	)		(19,113	)			(76,148	)
(Provision for) benefit from income taxes					(72,647	)		(24	)		31,020		[A2]		(41,651	)
Net income (loss)				$	(67,592	)	$	(62,114	)	$	11,907			$	(117,799	)

See Notes to Unaudited, Pro Forma Combined Financial Statements.

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GENZYME CORPORATION
UNAUDITED, PRO FORMA COMBINED STATEMENTS OF OPERATIONS
For the Year Ended December 31, 2003
(Amounts in thousands, except per share data)

			Historical Genzyme Corporation			Historical ILEX Oncology, Inc.	Pro Forma Adjustments			Footnote Reference	Pro Forma Genzyme Corporation
Net income (loss) per share:
Allocated to Genzyme General Stock:
	Net income (loss)		$	82,143			$	(50,207	)	[A3]	$	31,936
	Tax benefit allocated from Genzyme Biosurgery			8,720				—				8,720
	Tax benefit allocated from Genzyme Molecular Oncology			3,420				—				3,420
	Net income (loss) allocated to Genzyme General Stock		$	94,283			$	(50,207	)		$	44,076
	Net income per share of Genzyme General Stock:
		Basic	$	0.43							$	0.19
		Diluted	$	0.42							$	0.18
	Weighted average shares outstanding:
		Basic		219,376								237,755
		Diluted		225,419								244,083
Allocated to Biosurgery Stock (through June 30, 2003):
	Net loss		$	(166,656	)						$	(166,656	)
	Allocated tax benefit			14,005								14,005
	Net loss allocated to Biosurgery Stock		$	(152,651	)						$	(152,651	)
	Net loss per share of Biosurgery Stock—basic and diluted		$	(3.76	)						$	(3.76	)
	Weighted average shares outstanding			40,630								40,630
Allocated to Molecular Oncology Stock (through June 30, 2003):
	Net loss allocated to Molecular Oncology Stock		$	(9,224	)						$	(9,224	)
	Net loss per share of Molecular Oncology Stock—basic and diluted		$	(0.54	)						$	(0.54	)
	Weighted average shares outstanding			16,958								16,958

See Notes to Unaudited, Pro Forma Combined Financial Statements.

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GENZYME CORPORATION
UNAUDITED, PRO FORMA COMBINED BALANCE SHEETS
As of December 31, 2003
(Amounts in thousands, except par value amounts)

			Historical Genzyme Corporation			Historical ILEX Oncology, Inc.			Pro Forma Adjustments			Footnote Reference	Pro Forma Genzyme Corporation
Assets
Current assets:
	Cash and cash equivalents		$	292,774		$	63,154		$	—			$	355,928
	Short-term investments			120,712			77,314			—				198,026
	Restricted short-term investments			—			816			—				816
	Accounts receivable, net			397,439			8,529			—				405,968
	Inventories			267,472			—			—				267,472
	Prepaid expenses and other current assets			110,872			3,062			—				113,934
	Deferred tax assets			133,707			—			39,715		[A4]		173,422
		Total current assets		1,322,976			152,875			39,715				1,515,566
Property, plant and equipment, net				1,151,133			3,805			—				1,154,938
Long-term investments				813,974			56,209			—				870,183
Restricted long-term investments				—			1,691			—				1,691
Notes receivable—related parties				12,318			—			—				12,318
Goodwill, net				621,947			—			284,728		[A4]		906,675
Other intangible assets, net				895,844			59,826			228,874		[A4]		1,184,544
Investments in equity securities				110,620			—			—				110,620
Other noncurrent assets				75,716			689			—				76,405
		Total assets	$	5,004,528		$	275,095		$	553,317			$	5,832,940
Liabilities and Stockholders' Equity
Current liabilities:
	Accounts payable		$	97,474		$	11,477		$	—			$	108,951
	Accrued expenses			267,304			7,210			11,920		[A5]		286,434
	Deferred revenue			6,837			385			—				7,222
	Current portion of long-term debt, convertible note and capital lease obligations			20,410			38,390			—				58,800
		Total current liabilities		392,025			57,462			11,920				461,407
Long-term debt and capital lease obligations				150,349			—			—				150,349
Convertible notes and debentures				1,265,000			—			—				1,265,000
Deferred revenue—noncurrent				3,388			1,077			—				4,465
Deferred tax liabilities				205,923			—			40,385		[A4]		246,308
Other noncurrent liabilities				51,431			742			—				52,173
		Total liabilities		2,068,116			59,281			52,305				2,179,702
Commitments and contingencies
Stockholders' equity:
	Preferred stock, $0.01 par value			—			—			—				—
	Genzyme common stock, $0.01 par value			2,247			—			184		[A4]		2,431
	Additional paid-in capital—Genzyme common stock			2,957,578			—			991,242		[A4]		3,948,820
	Notes receivable from stockholders			(13,285	)		—			—				(13,285	)
	Accumulated deficit			(198,560	)		—			(274,600	)	[A4]		(473,160	)
	Accumulated other comprehensive income			188,432			—			—				188,432
	ILEX Oncology, Inc. convertible preferred stock, $0.01 par value			—			—			—		[A6]		—
	ILEX Oncology, Inc. common stock, $0.01 par value			—			390			(390	)	[A6]		—
	ILEX Oncology, Inc. additional paid-in capital			—			560,632			(560,632	)	[A6]		—
	ILEX Oncology, Inc. deferred compensation			—			(359	)		359		[A6]		—
	ILEX Oncology, Inc. accumulated deficit			—			(345,544	)		345,544		[A6]		—
	ILEX Oncology, Inc. accumulated other comprehensive income			—			695			(695	)	[A6]		—
		Total stockholders' equity		2,936,412			215,814			501,012				3,653,238
		Total liabilities and stockholders' equity	$	5,004,528		$	275,095		$	553,317			$	5,832,940

See Notes to Unaudited, Pro Forma Combined Financial Statements.

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NOTES TO UNAUDITED, PRO FORMA COMBINED FINANCIAL STATEMENTS

(1) ACCOUNTING POLICIES AND PRO FORMA INFORMATION

        The following unaudited, pro forma combined financial information describes the pro forma effect of Genzyme's proposed merger with ILEX on its statements of operations for the year ended December 31, 2003, as if the transaction had occurred on January 1, 2003, and balance sheet as of December 31, 2003, as if the transaction had occurred on that date. Certain historical financial information of ILEX has been reclassified to conform to the presentation of Genzyme's historical financial statements.

(2) PURCHASE PRICE ALLOCATION

        The estimated aggregate purchase price is comprised of the following (amounts in thousands):

Issuance of 18,379,383 shares of Genzyme common stock	$	946,722
Issuance of options to purchase 1,887,760 shares of Genzyme common stock		44,704
Transaction costs		7,310
Total purchase price	$	998,736

        Upon the closing of the transaction (the measurement date), the exchange ratio determining the number of shares of Genzyme common stock to be issued in the transaction will be established. The exact number of shares to be issued may change as a result of changes in the number of shares of ILEX common stock outstanding prior to closing and fluctuations in the price of Genzyme common stock. Assuming that a measurement date occurred on February 26, 2004, the date on which the transaction was announced, approximately 18.4 million shares of Genzyme common stock valued at $946.7 million would have been issued in exchange for the outstanding shares of ILEX common stock, based on the six day average trading price commencing two days before the assumed measurement date.

        Options to purchase approximately 4,010,538 shares of ILEX common stock will be exchanged for options to purchase approximately 1,887,760 shares of Genzyme common stock based on the assumed exchange ratio. Using the assumed value of Genzyme common stock to be issued in the transaction and certain other assumptions in the Black-Scholes option valuation model, the Genzyme options issued in exchange for the ILEX options were valued at approximately $44.7 million. The exact number of options to purchase shares of Genzyme common stock and the total value of these options to be issued may change as a result of changes in the number of options to purchase shares of ILEX common stock outstanding prior to closing and fluctuations in the closing price of Genzyme common stock.

        For purposes of the unaudited, pro forma combined financial statements, the aggregate purchase price of approximately $998.7 million was allocated to the acquired tangible and intangible assets and

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assumed liabilities of ILEX based on their estimated respective fair values as of December 31, 2003 (amounts in thousands):

Cash and cash equivalents		$	63,154
Short-term investments			77,314
Restricted short-term investments			816
Accounts receivable			8,529
Deferred tax assets-current			39,715
Other current assets			3,062
Long-term investments			56,209
Restricted long-term investments			1,691
Property, plant and equipment			3,805
Other intangible assets (to be amortized straight-line over 12 years)			288,700
Goodwill			284,728
In-process research and development			274,600
Other assets			689
Assumed liabilities:
	Note payable		(38,390	)
	Other assumed liabilities		(25,501	)
Deferred tax liability			(40,385	)
Allocated purchase price		$	998,736

        The total purchase price, the fair values of assets acquired and liabilities assumed, the allocation of purchase price and the lives of intangible assets will be determined upon completion of the transaction and may vary from the amounts Genzyme has presented in these unaudited, pro forma combined financial statements.

        In connection with the proposed transaction, we will acquire in-process research and development, or IPR&D, related to three development projects, CAMPATH (for indications other than B-cell chronic lymphocytic leukemia), clofarabine and ILX-651.

        CAMPATH is a humanized monoclonal antibody that binds to a specific target, CD52, on cell surfaces leading the body's immune system to destroy malignant, or cancerous, cells. CAMPATH was launched in May 2001 in the United States and in August 2001 in Europe under the name MABCAMPATH. The product is approved for use in patients with B-cell chronic lymphocytic leukemia who have been treated with alkylating agents and who have failed fludarabine therapy, and ILEX is now conducting trials in non-Hodgkin's lymphoma and multiple sclerosis as well.

        Clofarabine is a next-generation, purine nucleoside antimetabolite that is currently under investigation in pediatric and adult leukemias and solid tumors. ILEX has submitted the final section of its "rolling" New Drug Application with the FDA for acute pediatric leukemias based on phase II clinical trial data.

        ILX-651 is a next-generation synthetic pentapeptide analog of the natural substance dolastatin-15. This product candidate targets tubulin and has been chemically modified to provide improved pharmacological properties over earlier members of its class. ILEX initiated phase II clinical trials of ILX-651 in late 2003 in recurrent or metastatic melanoma and in locally advanced or metastatic non-small cell lung cancer.

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        As of December 31, 2003, none of these projects had reached technological feasibility nor had an alternative future use. Accordingly, Genzyme allocated to IPR&D, and charged to accumulated deficit in Genzyme's unaudited, pro forma combined balance sheet as of December 31, 2003, $274.6 million, representing the portion of the purchase price attributable to these projects, of which $115.8 million is attributable to the CAMPATH development project, $118.6 million is attributable to the clofarabine development project and $40.2 million is related to the ILX-651 development project. This will be charged to expense upon completion of the transaction. Material non-recurring charges such as IPR&D are not reflected in these unaudited, pro forma combined financial statements.

        Management assumes responsibility for determining the IPR&D valuation. The fair value assigned to purchased IPR&D was estimated by discounting, to present value, the cash flows expected to result from each project once it has reached technological feasibility. We used a discount rate of 11% and cash flows that have been probability-adjusted to reflect the risks of advancement through the product approval process. In estimating future cash flows, we also considered other tangible and intangible assets required for successful exploitation of the technology resulting from the purchased IPR&D projects and adjusted future cash flows for a charge reflecting the contribution to value of these assets.

(3) PRO FORMA ADJUSTMENTS

        The following adjustments reflect the exchange of ILEX common stock for Genzyme common stock in the transaction as well as the exchange of options to purchase shares of ILEX common stock for fully vested options to purchase shares of Genzyme common stock.

I. Unaudited, Combined Statements of Operations of Genzyme

(A1)

To record the amortization of acquired other intangible assets, all of which will be amortized straight-line over 12 years, for the year ended December 31, 2003 (amounts in thousands):

Other Intangible Assets:		Assigned Value		Annual Amortization
Developed technology		$	178,900	$	14,908
Core technology			105,500		8,792
Trademark			2,400		200
Technology license			1,900		158
	Total	$	288,700	$	24,058

(A2)

To adjust the tax provision for the impact of the historical losses of ILEX and the pro forma adjustments related to the proposed transaction.

(A3)

The pro forma adjustments to net income (loss) reflect the aggregate impact of all pro forma adjustments on Genzyme's income (loss) and the net losses of ILEX.

II. Unaudited, Combined Balance Sheets of Genzyme

(A4)

To record the assumption of the net assets of ILEX and the issuance of approximately 18,379,383 shares of Genzyme common stock.

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        The other intangible assets of approximately $288.7 million are comprised of the following (amounts in thousands):

Other Intangible Assets:		Assigned Value
Developed technology		$	178,900
Core technology			105,500
Trademark			2,400
Technology license			1,900
	Total	$	288,700

        Material non-recurring charges, such as the acquired IPR&D charge of $274.6 million resulting from the proposed transaction, are not reflected in Genzyme's unaudited, pro forma combined statements of operations for the year ended December 31, 2003. The $274.6 million allocated to in-process technology has been charged to accumulated deficit for purposes of the pro forma balance sheet presentation only and will be charged to expense in the statements of operations of Genzyme upon completion of the transaction.

(A5)

To accrue the following expenses which have not been reflected in Genzyme's historical balances as of December 31, 2003:

•

$7.3 million for the estimated merger costs Genzyme expects to incur; and

•

$4.6 million for severance and bonus payments to certain officers of ILEX that Genzyme will be contractually obligated to pay.

(A6)

To eliminate ILEX's historical stockholders' equity amounts totaling $215.8 million.

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UNAUDITED, PRO FORMA COMBINED FINANCIAL INFORMATION
NOTES TO UNAUDITED, PRO FORMA COMBINED FINANCIAL STATEMENTS