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): July 14, 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 7.    Financial Statements, Pro Forma Financial Information and Exhibits

(c)

Exhibits



99.1

Press Release of Genzyme Corporation dated July 14, 2004.

Item 12.    Results of Operations and Financial Condition

        On July 14, 2004, Genzyme Corporation issued a press release relating to its results of operations and financial condition for the three month period ended June 30, 2004. A copy of the press release is furnished as Exhibit 99.1 to this Form 8-K.

        The press release includes certain non-GAAP financial measures that involve adjustments to GAAP figures. Genzyme believes that these non-GAAP financial measures, when considered together with the GAAP figures, can enhance an overall understanding of Genzyme's past financial performance and its prospects for the future. The non-GAAP financial measures are included with the intent of providing both management and investors with a more complete understanding of underlying operational results and trends. In addition, these non-GAAP financial measures are among the primary indicators Genzyme management uses for planning and forecasting purposes. These non-GAAP financial measures are not intended to be considered in isolation or as a substitute for GAAP figures.

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
Dated: July 14, 2004	By:	/s/  MICHAEL S. WYZGA Michael S. Wyzga Executive Vice President, Finance; Chief Financial Officer; and Chief Accounting Officer

INDEX TO EXHIBITS

Exhibit No.	Description
99.1	Press Release of Genzyme Corporation dated July 14, 2004

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Item 7. Financial Statements, Pro Forma Financial Information and Exhibits
Item 12. Results of Operations and Financial Condition

SIGNATURE
INDEX TO EXHIBITS

EX-99.1

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Exhibit 99.1

For Immediate Release	Media Contact:	Investor Contact:
July 14, 2004	Bo Piela (617) 768-6579	Sally Curley (617) 768-6140

Genzyme Achieves Excellent Growth In Second Quarter

Expects Strong Performance to Offset Impact of Planned ILEX Merger;
Maintains Full-Year Non-GAAP EPS Guidance

        CAMBRIDGE, Mass.—Genzyme Corp. (Nasdaq: GENZ) today reported strong sales and earnings growth for the second quarter of 2004. The company also revised its financial guidance for the year—raising sales projections for several major products and businesses and increasing overall revenue guidance, while maintaining its non-GAAP EPS guidance in anticipation that strong top- and bottom-line growth will offset dilution from the expected merger with ILEX Oncology Inc.

        Total revenue rose 58 percent in the second quarter to reach $549.6 million, up from $347.7 million in the same period a year ago. The increase was driven by the outstanding performance of Fabrazyme® (agalsidase beta) and Renagel® (sevelamer hydrochloride) and also reflects important contributions from other businesses, including the recently integrated biosurgery and transplant businesses. Results for last year's second quarter represent the operations of the Genzyme General division only. Genzyme consolidated its capital structure on June 30, 2003, by eliminating its tracking stocks. The company now expects total revenue for 2004 to reach $2.065-$2.185 billion, an increase from previous guidance of $1.930-$2.030 billion.

        Net income for the second quarter was $78.2 million, or $0.34 per diluted share, compared with net income of $70.8 million, or $0.32 per diluted share, for the same quarter last year. Excluding special items and amortization, net income increased 36 percent to $102.2 million, or $0.44 per share, compared with $75.3 million, or $0.34 per share, in the second quarter a year ago.

        Special items included $9.6 million, or $0.03 per share, in expenses associated with the redemption of Genzyme's 3 percent convertible subordinated debentures, and a charge of $1.1 million related to the sale of inventory acquired from SangStat Medical Corp. Amortization amounted to $27.2 million, or $0.07 per share.

        Genzyme now expects to report GAAP earnings this year of $1.35-$1.40 per share. Amortization for the year—including the impact of the anticipated ILEX merger and the acquisition of IMPATH Inc.'s oncology testing business—is expected to be approximately $119 million, compared with previous guidance of $103 million. Genzyme continues to expect to report non-GAAP earnings of $1.65-$1.75 per share for 2004, consistent with previous guidance.

        This guidance reflects six months of the anticipated impact of the ILEX merger, which is expected to close this summer following clearance by the Federal Trade Commission. Genzyme believes it has made excellent progress in its discussions with the FTC staff, and the company has submitted a draft settlement agreement that is now under review. Genzyme believes that it will soon reach agreement in principle with the FTC regarding a settlement. ILEX shareholders recently approved the proposed merger. Genzyme expects to issue a maximum of approximately 22 million shares to complete the merger, which would increase the weighted average number of shares of Genzyme stock outstanding for the full year to approximately 240 million.

        "Genzyme had a very strong first two quarters and is moving forward into the second half of the year with significant momentum," said Henri A. Termeer, chairman and chief executive officer of Genzyme Corp. "The strength of our top and bottom lines continues to allow us to build and diversify the company by investing in R&D and completing transactions that add important programs."

        Genzyme expects earnings of $0.42-$0.44 per share in the third quarter of this year. The company reiterated its goal of delivering earnings growth of approximately 20 percent annually.

        Selling, general and administrative expenses in the second quarter totaled $152.9 million, compared with $95.2 million in the same quarter last year. The increase in SG&A expenses reflects the integration of the SangStat and IMPATH businesses, along with the addition of Genzyme's Biosurgery and Molecular Oncology units. SG&A expenses for the year—including the IMPATH and ILEX transactions—are now projected to be $605-$615 million, compared with previous guidance of $565-$575 million.

        Research and development spending totaled $97.5 million before the impact of FIN46, compared with $58.8 million in the second quarter year ago, reflecting the addition of the SangStat, Biosurgery and Molecular Oncology businesses. For the year, R&D expenses are now expected to be $410-$420 million, including the anticipated addition of ILEX programs. Previous guidance was $385-$395 million.

        The company's effective net tax rate was 30 percent for the second quarter. Excluding special items and amortization, it was 31.7 percent. For the year, the tax rate is expected to be 29 percent. Excluding special items and amortization, the tax rate is expected to be approximately 31 percent, within the previous guidance range.

        Following the redemption of its 3 percent convertible subordinated debentures and the completion of its acquisition of IMPATH's oncology testing business, Genzyme ended the second quarter with $657.0 million in cash and marketable securities.

Product Revenues

        Genzyme's revenues are allocated within six segments: Renal, Therapeutics, Biosurgery, Transplant, Diagnostics/Genetics, and Other.

        Within the Renal business, Renagel revenue grew 33 percent to $87.6 million, up from $66.0 million in the second quarter last year. Renagel revenue includes product sales, royalties on product sales in Japan, and sales of bulk sevelamer to Chugai Pharmaceutical Co. Ltd., Genzyme's commercial partner in Japan. Renagel revenue for the year is now expected to be $335-$355 million, compared with previous guidance of $325-$345 million, driven by growing penetration of existing markets and efforts to increase dose levels and improve patient compliance.

        Total Therapeutics revenues for the second quarter were $276.5 million, 31 percent higher than the $210.4 million recorded in the same period a year ago. Therapeutics revenues are now expected to reach $1.037-$1.083 billion this year, compared with previous guidance of $990 million-$1.030 billion.

        Within the Therapeutics business, sales of Fabrazyme enzyme replacement therapy for Fabry disease more than tripled to $49.6 million, up from $15.4 million in the same quarter last year. Approximately $19.5 million of second-quarter sales came from the United States. Fabrazyme's growth is being driven by a steady increase in the number of patients on therapy in both the United States and Europe, along with the rapid adoption of the product in Japan, where Fabrazyme was introduced during the second quarter. Recent launches in Canada, Australia and other markets will start to contribute to sales growth in the second half of this year. Genzyme now expects Fabrazyme revenue to reach $185-$200 million in 2004, an increase from previous guidance of $170-$185 million. Approximately 1,200 patients are now receiving Fabrazyme around the world.

        Sales of Cerezyme® (imiglucerase for injection) enzyme replacement therapy for Type 1 Gaucher disease were $209.4 million for the quarter, up 13 percent from $184.7 million from the same period a year ago. For the year, Cerezyme sales are expected to reach $800-$820 million, an increase from

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previous guidance of $770-$790 million. Approximately 4,000 patients are receiving Cerezyme worldwide.

        Sales of Aldurazyme® (laronidase) enzyme replacement therapy for patients with MPS I were $9.2 million in the second quarter, compared with $1.1 million in the same quarter last year. Approximately 300 patients are currently receiving Aldurazyme globally, and Genzyme continues to identify new patients by reaching out to pediatricians, geneticists and other physician groups. The company is commercializing Aldurazyme through a joint venture with BioMarin Pharmaceutical Inc. Therefore, Aldurazyme sales are not included within Genzyme revenues.

        Sales of Thyrogen® (thyrotropin alfa for injection) increased 67 percent to $16.3 million, compared with $9.8 million in last year's second quarter. For the year, Thyrogen sales are expected to reach $50-$60 million, an increase from previous guidance of $48-$52 million. The product is currently indicated for use as an adjunctive diagnostic in follow-up screenings of thyroid cancer patients. Its growth is being driven by an expanding body of peer-reviewed literature addressing the importance of careful management of thyroid cancer patients and a growing appreciation of the role of Thyrogen in patient follow up.

        Genzyme is seeking to expand Thyrogen's use to therapeutic applications, and during the quarter it reported promising results from a comparative clinical study evaluating the product as a therapy for the ablation of thyroid tumor remnants. The company intends to file for a label expansion in Europe based on these results, and to continue discussions with the FDA about a U.S. filing. Genzyme is also studying the use of Thyrogen for the treatment of goiter.

        Revenue for the Biosurgery business unit was $59.6 million for the second quarter, and Genzyme now expects the unit's revenue to reach $208-$222 million this year, compared with previous guidance of $213-$225 million. Sales of the Biosurgery unit's largest product, Synvisc® (hylan G-F 20), which is used to treat knee pain for osteoarthritis, were $27.5 million in the quarter. For the year, Genzyme now expects Synvisc sales of $100-$105 million, compared with previous guidance of $110-$115 million.

        Within the Biosurgery business in the second quarter, Genzyme also received U.S. marketing approval for Hylaform® (Hylan-B gel), a cosmetic dermal filler for the correction of facial wrinkles. The product is distributed by Inamed Corp.

        Revenue for Genzyme's Transplant business was $36.5 million for the second quarter. Sales of Thymoglobulin® (anti-thymocyte globulin, rabbit) and Lymphoglobuline® (anti-thymocite-globulin, equine), were $25.3 million in the quarter. These products, which Genzyme acquired with the purchase of SangStat in September 2003, are used to treat acute rejection in renal transplant patients.

        Revenue for Genzyme's Diagnostics/Genetics segment grew 50 percent to $71.7 million, up from $47.9 million in last year's second quarter. Within this area, revenue for genetic testing services nearly doubled compared with the same period last year, bolstered by revenue from IMPATH's oncology testing business, which Genzyme acquired on May 1, 2004. Revenue for genetic testing services is now expected to reach $185-$195 million this year, up from $110-$120 million. Based on this projected growth, Genzyme increased guidance for its Diagnostics/Genetics segment to $275-$290 million, up from $200-$215 million.

        Other revenue—including sales of WelChol® (colesevelum hydrochloride) and pharmaceutical intermediates—totaled $17.7 million in the second quarter, compared with $19.7 million for the same period last year.

        Genzyme's guidance for 2004 now includes $15-$20 million in Oncology revenues, in anticipation of the completion of the ILEX merger.

        Complete financial guidance for Genzyme Corp. follows this release in an accompanying table, along with other financial statements.

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Pipeline Highlights

        During the second quarter, Genzyme made important progress within a number of its development programs. Within its Myozyme® (alglucosidase alfa) program, the company completed enrollment in three clinical trials: Studies 1602 and 1702 for patients with infantile-onset Pompe disease, and Study 2303 for patients with late-onset Pompe disease. The latter is an observational study that will help define the parameters of a subsequent treatment trial. Genzyme remains on track to submit a marketing application for Myozyme in Europe at the end of this year and to submit applications in Japan and the United States in the middle of next year.

        Also during the quarter, Genzyme and its joint venture partner Dyax Corp. announced that the EDEMA1 clinical trial had met its primary endpoint. The trial is evaluating the use of DX-88 for the treatment of Hereditary Angioedema. The companies plan to meet with regulatory authorities in the coming months to discuss the submission of marketing applications based on the results of this Phase 2 study and the ongoing open-label EDEMA2 trial.

        Last month, Genzyme formed a joint venture with Medtronic Inc. to accelerate the development of innovative new treatments for heart disease. The companies will focus on completing an ongoing Phase 2 clinical trial investigating the use of cell therapy to repair damaged heart tissue, developing a portfolio of advanced delivery devices that will locally deliver therapeutic cells to the heart in a less invasive manner, and conducting long-term cell therapy research into repairing damaged heart tissue.

About Genzyme

        Genzyme Corp. is a global biotechnology company dedicated to making a major positive impact on the lives of people with serious diseases. The company's broad product portfolio is focused on rare genetic disorders, renal disease, osteoarthritis and immune-mediated diseases, and includes an industry-leading array of diagnostic products and services. Genzyme's commitment to innovation continues today with research into novel approaches to cancer, heart disease, and other areas of unmet medical need. More than 6,400 Genzyme employees in offices around the globe serve patients in over 80 countries. Genzyme's press releases and other company information are available at www.genzyme.com and by calling Genzyme's investor information line at 1-800-905-4369 within the United States or 1-703-797-1866 outside the United States.

Safe-harbor paragraph

        This press release contains forward-looking statements, including statements regarding third-quarter and full-year financial guidance, earnings growth, timing for the completion of the ILEX merger and the expected financial impact of the transaction, expansion plans for Thyrogen, timing for the submission of regulatory approval applications for Myozyme, plans to meet with regulatory authorities regarding approval of DX-88, and other statements regarding Genzyme's future performance and strategy. These statements are subject to risks and uncertainties that could cause actual results to differ materially from those forecast in these forward-looking statements. These risks and uncertainties include, among others, Genzyme's ability to consummate the ILEX merger and its ability to successfully integrate that business; Genzyme's ability successfully to complete preclinical and clinical development of its product candidates, including Myozyme; Genzyme's ability to expand the use of current products in existing and new indications, including Thyrogen, Renagel, Synvisc, and Thymoglobulin; Genzyme's ability to maintain and obtain regulatory approvals for products and services; Genzyme's ability to successfully identify and market to new patients; the accuracy of Genzyme's estimates regarding patient populations; Genzyme's success in marketing its products and services against new and existing competitive products and services; the availability and amount of reimbursement for Genzyme's products and services from third-party payors; Genzyme's ability to manufacture products and product candidates in a timely and cost effective manner; Genzyme's ability

4

to effectively manage inventory levels; changes in legislation and regulations affecting the sale of Genzyme's products and services; and the other factors described in Genzyme's periodic filings with the Securities and Exchange Commission. Please see the disclosure under the heading "Factors Affecting Future Operating Results" in the Management's Discussion and Analysis of Financial Condition and Results of Operations section of the Genzyme Quarterly Report on Form 10-Q for the year quarter ending March 31, 2004, for a more complete discussion of these and other risk factors. Genzyme cautions investors not to place substantial reliance on the forward-looking statements contained in this press release. These statements speak only as of July 14, 2004, and Genzyme undertakes no obligation to update or revise the statements.

        Genzyme®, Cerezyme®, Fabrazyme®, Renagel®, Thyrogen®, Synvisc® and Hylaform® are registered trademarks and Myozyme™ is a trademark of Genzyme Corporation. Aldurazyme® is a registered trademark of BioMarin/Genzyme LLC. WelChol® is a registered trademark of Sankyo Pharma Inc. SangStat® and Thymoglobulin® and Lymphoglobulin® are registered trademarks of SangStat Medical Corporation or its subsidiaries. All rights reserved.

Conference Call Information

        There will be a conference call today at 11:00 a.m. EDT to discuss Genzyme Corporation's second quarter 2004 financial results. If you would like to participate in the call, please dial 719-457-2642. A replay of this call will be available from 2:30 p.m. EDT today through midnight on July 21 by dialing 719-457-0820. Please refer to reservation number 558367. This call will also be Webcast live on the investor events section of www.genzyme.com.

Upcoming Events

        Genzyme will report its third quarter financial results on October 20. If you would like to participate in the call please dial 719-457-2642. A replay of this call will be available through midnight EDT on October 27 by dialing 719-457-0820. Please refer to reservation number 205889. Please check www.genzyme.com one week prior to the reporting date for any changes to this information.

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GENZYME CORPORATION
Consolidated Statements of Operations
(Unaudited, amounts in thousands, except per share amounts)

				Three Months Ended June 30,						Six Months Ended June 30,
				2004			2003			2004			2003
Total revenues				$	549,588		$	418,903		$	1,040,839		$	800,762
Operating costs and expenses:
	Cost of products and services sold				142,868			119,577			269,830			231,389
	Selling, general and administrative				152,850			130,807			296,070			245,031
	Research and development				99,370			79,063			192,186			154,694
	Amortization of intangibles				27,245			17,641			53,490			35,146
	Charge for impairment of goodwill(1)				—			102,792			—			102,792
	Charge for impaired asset(2)				—			2,898			—			2,898
		Total operating costs and expenses			422,333			452,778			811,576			771,950
Operating income (loss)					127,255			(33,875	)		229,263			28,812
Other income (expenses):
	Equity in loss of equity method investments				(4,274	)		(4,804	)		(8,105	)		(8,998	)
	Gain (loss) on investments in equity securities				71			(3,620	)		424			(3,620	)
	Minority interest				964			—			2,126			—
	Loss on sale of product line(3)				—			(29,367	)		—			(29,367	)
	Other				(390	)		769			(714	)		1,519
	Investment income				5,603			12,428			13,279			24,042
	Interest expense(4)				(17,495	)		(6,335	)		(27,821	)		(12,825	)
		Total other income (expenses)			(15,521	)		(30,929	)		(20,811	)		(29,249	)
Income (loss) before income taxes					111,734			(64,804	)		208,452			(437	)
Provision for income taxes					(33,558	)		(9,726	)		(62,382	)		(28,724	)
Net income (loss)				$	78,176		$	(74,530	)	$	146,070		$	(29,161	)
Net income (loss) per share:
	Allocated to Genzyme General Stock(5):
		Net income		$	78,176		$	62,781		$	146,070		$	120,574
		Tax benefit allocated from Genzyme Biosurgery			—			6,398			—			8,720
		Tax benefit allocated from Genzyme Molecular Oncology			—			1,657			—			3,420
		Net income allocated to Genzyme General Stock		$	78,176		$	70,836		$	146,070		$	132,714
		Net income per share of Genzyme General Stock:
			Basic	$	0.35		$	0.33		$	0.65		$	0.62
			Diluted(6)	$	0.34		$	0.32		$	0.63		$	0.60
		Weighted average shares outstanding:
			Basic		226,578			216,313			226,145			215,702
			Diluted(6)		231,544			222,867			231,731			221,650

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			Three Months Ended June 30,				Six Months Ended June 30,
			2004	2003			2004	2003
Net income (loss) per share (continued):
	Allocated to Biosurgery Stock(5):
		Net loss	—	$	(152,554	)	—	$	(166,656	)
		Allocated tax benefit	—		11,597		—		14,005
		Net loss allocated to Biosurgery Stock	—	$	(140,957	)	—	$	(152,651	)
		Net loss per share of Biosurgery Stock—basic and diluted:		$	(3.46	)		$	(3.76	)
		Weighted average shares outstanding	—		40,681		—		40,630
	Allocated to Molecular Oncology Stock(5):
		Net loss allocated to Molecular Oncology Stock	—	$	(4,409	)	—	$	(9,224	)
		Net loss per share of Molecular Oncology Stock—basic and diluted	—	$	(0.26	)	—	$	(0.54	)
		Weighted average shares outstanding	—		16,978		—		16,958

(1)

Represents the write off of the goodwill allocated to our orthopaedics reporting unit in June 2003 in accordance with Statement of Financial Accounting Standards No. 142, "Goodwill and Other Intangible Assets."

(2)

Represents the impairment charge recorded in June 2003 to write down the carrying value of our cardiothoracic devices manufacturing facility in Fall River, Massachusetts to fair value.

(3)

Represents the estimated net loss on the sale of our cardiothoracic devices business to Teleflex Inc. in June 2003, which we allocated to the Biosurgery division.

(4)

In June 2004, we completed the redemption of our 3% convertible subordinated debentures for cash, including $575.0 million in principal, accrued interest of approximately $0.8 million and $4.3 million in premium. Interest expense for the three and six months ended June 30, 2004 includes charges of $4.3 million for the premium paid upon redemption and $5.3 million to write off the unamortized debt fees associated with these debentures.

(5)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating earnings to Biosurgery Stock and Molecular Oncology Stock. From that date forward, all of our earnings are allocated to Genzyme General Stock. Earnings or losses allocated to Biosurgery Stock and Molecular Oncology Stock prior to July 1, 2003 remain allocated to those stocks and are not affected by the elimination of our tracking stock structure.

(6)

Net income per share on a diluted basis and weighted average shares-diluted for all periods presented include the dilutive effect of options, stock purchase rights and warrants to purchase shares of Genzyme General Stock, but exclude the potentially dilutive effect of the assumed conversion of our convertible subordinated debentures and notes because the conditions for conversion had not been met.

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GENZYME CORPORATION
Condensed Consolidated Balance Sheets
(Unaudited, amounts in thousands)

		June 30, 2004		December 31, 2003
Cash and all marketable securities(1)		$	657,047	$	1,227,460
Other current assets			944,828		909,490
Property, plant and equipment, net			1,202,580		1,151,133
Intangibles, net			1,698,383		1,517,791
Other assets			201,885		198,654
	Total assets	$	4,704,723	$	5,004,528
Current liabilities		$	512,570	$	392,025
Noncurrent liabilities(1)			1,068,496		1,676,091
Stockholders' equity			3,123,657		2,936,412
	Total liabilities and stockholders' equity	$	4,704,723	$	5,004,528

(1)

In June 2004, we completed the redemption of our 3% convertible subordinated debentures for cash, including $575.0 million in principal, accrued interest of approximately $0.8 million and $4.3 million in premium. Upon redemption, we also recorded a non-cash charge of $5.3 million to interest expense to write off the unamortized debt fees associated with these debentures.

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Genzyme Corporation
Guidance Analysis

			FY 2004 Original Guidance February 19, 2004						FY 2004 Revised Base Guidance July 14, 2004						Impact of Impath Guidance*						Impact of Ilex Guidance**						FY 2004 Revised Guidance July 14, 2004
Revenue
	Cerezyme			770			790			800			820															800			820
	Fabrazyme			170			185			185			200															185			200
	Thyrogen			48			52			50			60															50			60
	Other			2			3			2			3															2			3
		Total Therapeutics		990			1030			1037			1083			0			0			0			0			1037			1083
	Renal			325			345			335			355															335			355
	Thymoglobulin			90			100			90			100															90			100
	Other Products			40			45			40			45															40			45
		Total Transplant		130			145			130			145			0			0			0			0			130			145
	Synvisc			110			115			100			105															100			105
	Sepra			58			62			58			62															58			62
	Other Biosurgery			45			48			50			55															50			55
		Total Biosurgery		213			225			208			222			0			0			0			0			208			222
	Total Oncology			N/A			N/A			0			0									15			20			15			20
	Diagnostic Products			90			95			90			95															90			95
	Genetic Testing			110			120			120			125			65			70									185			195
		Total Diag/Genetics		200			215			210			220			65			70			0			0			275			290
	Total Other Products			65			70			65			70															65			70
		Total Revenue		1930			2030			1985			2095			65			70			15			20			2065			2185
	Gross Margin			76	%		77	%		76	%		77	%		35	%		40	%		100	%		100	%		75	%		76	%
		SG&A		(565	)		(575	)		(575	)		(585	)		(19	)		(21	)		(7	)		(9	)		(605	)		(615	)
		R&D		(385	)		(395	)		(385	)		(395	)		(2	)		(3	)		(20	)		(22	)		(410	)		(420	)
		Amortization		(103	)		(103	)		(103	)		(103	)		(3	)		(3	)		(12	)		(12	)		(119	)		(119	)
		Net Interest		(1	)		1			(5	)		(5	)														(5	)		(5	)
		Net Other		(14	)		(15	)		(15	)		(15	)														(15	)		(15	)
		Tax Rate		29	%		31	%		31	%		31	%		31	%		31	%		31	%		31	%		31	%		31	%
		GAAP EPS	$	1.37		$	1.47		$	1.40		$	1.50		$	0.00		$	0.00		($	0.08	)	($	0.10	)	$	1.35		$	1.40
		Amortization	$	0.28		$	0.28		$	0.28		$	0.28		$	0.00		$	0.00		$	0.02		$	0.02		$	0.31		$	0.31
		One Time Items	$	0.00		$	0.00		$	0.04		$	0.04		$	0.00		$	0.00		$	0.00		$	0.00		$	0.04		$	0.04
		Non-GAAP EPS	$	1.65		$	1.75		$	1.72		$	1.82		$	0.00		$	0.00		($	0.06	)	($	0.08	)	$	1.65		$	1.75
		Wtd Avg Shares O/S		230			230			231			231			0			0			9			11			240			240
		Capex		180			200			180			200															180			200

*

Acquired IMPATH on May 1, 2004.

**

Assuming 6 months, as if closed July 1, 2004, excluding the impact of anticipated IPR&D.

Note: Guidance Crosswalk is illustrative of individual line item ranges.
            Not meant to be exactly additive.

This financial guidance, which is provided as part of a press release dated July 14, 2004, is subject to all of the qualifications and limitations described therein. Actual results may differ from these forward-looking statements due to numerous factors described in the press release.

9

Genzyme General (GENZ)
Analyst Schedule
(Unaudited, amounts in thousands, except percentage amounts)

				Q2-03		Q3-03(1)		Q4-03(1)		Q1-04(1)		Q2-04(1)		Q2-04 vs. Q2-03 % B/(W)		FY 2002		FY 2003(1)		YTD 06/30/04(1)
Total revenues:
	Renal
		Renagel phosphate binder (including Sevelamer)		$	66,002	$	75,468	$	81,465	$	83,523	$	87,617	33	%	$	156,864	$	281,701	$	171,140
		Other Renal			—		—		—		—		—	—			—		—
			Total Renal product and service revenue		66,002		75,468		81,465		83,523		87,617	33	%		156,864		281,701		171,140
		Renal R&D revenue			—		—		—		—		—				—		—		—
			Total Renal		66,002		75,468		81,465		83,523		87,617	33	%		156,864		281,701		171,140
	Therapeutics
		Cerezyme enzyme			184,724		189,223		192,683		202,970		209,371	13	%		619,184		733,817		412,341
		Fabrazyme enzyme			15,430		21,452		31,889		38,103		49,620	222	%		26,101		80,617		87,723
		Thyrogen hormone			9,790		11,405		12,529		13,997		16,298	66	%		28,270		43,438		30,295
		Other Therapeutics			448		499		448		39		1,193	166	%		871		1,802		1,232
			Total Therapeutics product and service revenue		210,392		222,579		237,549		255,109		276,482	31	%		674,426		859,674		531,591
		Therapeutics R&D revenue			1		—		—		—		—	(100	%)		834		1		—
		Total Therapeutics			210,393		222,579		237,549		255,109		276,482	31	%		675,260		859,675		531,591
	Transplant
		Thymoglobulin/Lymphoglobuline			—		4,898		25,055		25,012		25,260				—		29,953		50,272
		Other Transplant			—		2,421		11,946		11,222		11,235				—		14,367		22,457
			Total Transplant product and service revenue		—		7,319		37,001		36,234		36,495				—		44,320		72,729
		Transplant R&D revenue			—		—		—		—		—				—		—		—
			Total Transplant		—		7,319		37,001		36,234		36,495				—		44,320		72,729
	Biosurgery
		Synvisc viscosupplementation product and services			—		29,754		25,825		22,363		27,520				—		55,579		49,883
		Sepra products			—		11,951		14,008		14,212		15,579				—		25,959		29,791
		Other Biosurgery			3,628		12,969		13,003		10,807		14,178	291	%		12,828		32,414		24,985
			Total Biosurgery product and service revenue		3,628		54,674		52,836		47,382		57,277	1479	%		12,828		113,952		104,659
		Biosurgery R&D revenue			—		4,721		406		321		2,302				—		5,127		2,623
			Total Biosurgery		3,628		59,395		53,242		47,703		59,579	1542	%		12,828		119,079		107,282
	Diagnostics/Genetics
		Diagnostic Products			22,554		21,116		21,722		23,370		22,917	2	%		83,065		88,588		46,287
		Genetic Testing			25,379		25,530		26,736		28,744		48,809	92	%		89,745		102,147		77,553
			Total Diagnostics/Genetics product and service revenue		47,933		46,646		48,458		52,114		71,726	50	%		172,810		190,735		123,840
		Diagnostic/Genetics R&D revenue			—		—		—		—		—				—		—		—
			Total Diagnostics/Genetics		47,933		46,646		48,458		52,114		71,726	50	%		172,810		190,735		123,840
	Other
		Other product and service revenue			18,919		21,487		16,242		14,784		16,444	(13	%)		57,084		71,710		31,228
		Other R&D revenue			788		4,084		2,174		1,784		1,245	58	%		5,339		7,597		3,029
			Total Other		19,707		25,571		18,416		16,568		17,689	(10	%)		62,423		79,307		34,257
Total revenues				$	347,663	$	436,978	$	476,131	$	491,251	$	549,588	58	%	$	1,080,185	$	1,574,817	$	1,040,839

10

			Q2-03			Q3-03(1)			Q4-03(1)			Q1-04(1)			Q2-04(1)			Q2-04 vs. Q2-03 % B/(W)		FY 2002			FY 2003(1)			YTD 06/30/04(1)
Revenues:
	Total product and service revenue		$	346,874		$	428,173		$	473,551		$	489,146		$	546,041		57	%	$	1,074,012		$	1,562,092		$	1,035,187
	Total R&D revenue			789			8,805			2,580			2,105			3,547		350	%		6,173			12,725			5,652
		Total revenues		347,663			436,978			476,131			491,251			549,588		58	%		1,080,185			1,574,817			1,040,839
Total product and service gross profit				255,200			313,310			344,159			362,184			403,173		58	%		808,194			1,143,123			765,357
SG&A expense				95,203			127,340			147,606			143,220			152,850		(61	%)		323,683			455,395			296,070
R&D expense				58,834			82,974			97,588			92,816			99,370		(69	%)		230,043			295,725			192,186
Amortization of intangibles				9,873			19,267			25,844			26,245			27,245		(176	%)		38,998			64,720			53,490
Purchase of in-process research and development(2)				—			158,000			—			—			—					—			158,000			—
Charge for impaired assets(3)				—			7,996			—			—			—					13,986			7,996			—
Operating income (loss)				92,079			(73,462	)		75,701			102,008			127,255		38	%		207,657			174,012			229,263
Other income (expenses):
	Equity in loss of equity method investments			(4,804	)		(5,503	)		(2,242	)		(3,831	)		(4,274	)	11	%		(16,858	)		(16,743	)		(8,105	)
	Gain (loss) on investments in equity securities			(3,620	)		1,183			1,236			353			71		102	%		(14,497	)		(1,201	)		424
	Minority interest			—			—			2,232			1,162			964					—			2,232			2,126
	Gain on sale of product line(4)			—			—			1,709			—			—					—			1,709			—
	Other			774			(338	)		(222	)		(324	)		(390	)	(150	%)		(152	)		994			(714	)
	Investment income			12,058			11,422			7,551			7,676			5,603		(54	%)		48,944			42,312			13,279
	Interest expense(5)			(4,328	)		(4,382	)		(9,393	)		(10,326	)		(17,495	)	(304	%)		(17,847	)		(22,380	)		(27,821	)
Income (loss) before income taxes				92,159			(71,080	)		76,572			96,718			111,734		21	%		207,247			180,935			208,452
Provision for income taxes				(29,378	)		(24,653	)		(19,270	)		(28,824	)		(33,558	)	(14	%)		(56,516	)		(98,792	)		(62,382	)
Division net income (loss) before allocated tax benefits				62,781			(95,733	)		57,302			67,894			78,176		25	%		150,731			82,143			146,070
Allocated tax benefits				8,055			—			—			—			—		(100	%)		27,795			12,140			—
Net income (loss) allocated to Genzyme General Stock(6)			$	70,836		$	(95,733	)	$	57,302		$	67,894		$	78,176		10	%	$	178,526		$	94,283		$	146,070
Net income (loss) per share of Genzyme General Stock-diluted(6,7,8)			$	0.32		$	(0.43	)	$	0.25		$	0.29		$	0.34		6	%	$	0.81		$	0.42		$	0.63
Weighted average shares outstanding-diluted(7,8)				222,867			222,000			229,970			231,917			231,544		4	%		219,388			225,419			231,731

11

			Q2-03			Q3-03(1)			Q4-03(1)			Q1-04(1)			Q2-04(1)			FY 2002			FY 2003(1)			YTD 06/30/04(1)
Total product and service revenue			$	346,874		$	428,173		$	473,551		$	489,146		$	546,041		$	1,074,012		$	1,562,092		$	1,035,187
As a % of total product and service revenue:
	Renagel (including Sevelamer)			19	%		17	%		17	%		17	%		16	%		15	%		18	%		16	%
	Cerezyme enzyme			53	%		44	%		41	%		41	%		38	%		58	%		47	%		40	%
	Fabrazyme enzyme			4	%		5	%		7	%		8	%		9	%		2	%		5	%		8	%
	Thyrogen hormone			3	%		3	%		3	%		3	%		3	%		3	%		3	%		3	%
	Thymoglobulin/Lymphoglobuline			0	%		1	%		5	%		5	%		5	%		0	%		2	%		5	%
	Synvisc viscosupplementation product and services			0	%		7	%		5	%		5	%		5	%		0	%		3	%		5	%
	Sepra products			0	%		3	%		3	%		3	%		3	%		0	%		2	%		3	%
	Diagnostics/Genetics			14	%		11	%		10	%		11	%		13	%		16	%		12	%		12	%
	Other			7	%		9	%		9	%		7	%		8	%		6	%		8	%		8	%
Total product and service gross margin				74	%		73	%		73	%		74	%		74	%		75	%		73	%		74	%
Total revenues			$	347,663		$	436,978		$	476,131		$	491,251		$	549,588		$	1,080,185		$	1,574,817		$	1,040,839
SG&A expense as % of total revenue				27	%		29	%		31	%		29	%		28	%		30	%		29	%		28	%
R&D expense as % of total revenue				17	%		19	%		20	%		19	%		18	%		21	%		19	%		18	%
Operating income (loss) as % of total revenue				26	%		(17	%)		16	%		21	%		23	%		19	%		11	%		22	%
Provision for income taxes as % of profit (loss) before tax				23	%		(35	%)		25	%		30	%		30	%		14	%		48	%		30	%
Balance sheet trends:				06/30/03			9/30/03(9	)		12/31/03(9	)		03/31/04(9	)		06/30/04(9	)		12/31/02			12/31/03(9	)		06/30/04(9	)
	Cash and all marketable securities		$	1,263,949		$	869,912		$	1,227,460		$	1,235,859		$	657,047		$	1,149,145		$	1,227,460		$	657,047
	Other current assets			673,076			842,180			909,490			907,286			944,828			633,501			909,490			944,828
	Property, plant and equipment, net			841,175			926,569			1,151,133			1,156,083			1,202,580			749,840			1,151,133			1,202,580
	Intangibles, net			925,890			1,537,571			1,517,791			1,537,411			1,698,383			933,360			1,517,791			1,698,383
	Other assets			122,556			151,084			198,654			208,805			201,885			89,955			198,654			201,885
		Total assets	$	3,826,646		$	4,327,316		$	5,004,528		$	5,045,444		$	4,704,723		$	3,555,801		$	5,004,528		$	4,704,723
	Current liabilities		$	284,563		$	735,976		$	392,025		$	922,995		$	512,570		$	274,872		$	392,025		$	512,570
	Noncurrent liabilities			676,602			815,637			1,676,091			1,082,140			1,068,496			695,045			1,676,091			1,068,496
	Stockholders' equity			2,865,481			2,775,703			2,936,412			3,040,309			3,123,657			2,585,884			2,936,412			3,123,657
		Total liabilities and stockholders' equity	$	3,826,646		$	4,327,316		$	5,004,528		$	5,045,444		$	4,704,723		$	3,555,801		$	5,004,528		$	4,704,723

12

Notes:

(1)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating earnings to Genzyme Biosurgery and Genzyme Molecular Oncology. From that date forward, all of our earnings are allocated to Genzyme General. Earnings or losses allocated to Genzyme Biosurgery and Genzyme Molecular Oncology prior to July 1, 2003 remain allocated to those divisions and are not affected by the elimination of our tracking stock structure.

(2)

Represents charges for the purchase of in-process research and development of $(158,000)K recorded in September 2003 related to our acquisition of SangStat Medical Corporation.

(3)

Includes impairment charges of $(7,996)K recorded in September 2003 to write down the assets of our FocalSeal business and $(13,986)K recorded in December 2002 to write off engineering costs related to a proposed manufacturing facility in Framingham, Massachusetts.

(4)

Represents the final adjustment to the net loss on the sale of our cardiothoracic devices business to Teleflex Inc. in accordance with the sale agreement. We recorded an estimated net loss of $(29,367)K in June 2003, which we allocated to the Biosurgery division. However, as a result of the elimination of our tracking stock capital structure effective July 1, 2003, the final adjustment to the net loss is allocated to Genzyme General.

(5)

In June 2004, we completed the redemption of our 3% convertible subordinated debentures for cash, including $575.0 million in principal, accrued interest of approximately $0.8 million and $4.3 million in premium. Interest expense for the three and six months ended June 30, 2004 includes charges of $(4,313)K for the premium paid upon redemption and $(5,329)K to write off the unamortized debt fees associated with these debentures.

(6)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating earnings to Biosurgery Stock and Molecular Oncology Stock. From that date forward, all of our earnings are allocated to Genzyme General Stock. Earnings or losses allocated to Biosurgery Stock and Molecular Oncology Stock prior to July 1, 2003 remain allocated to those stocks and are not affected by the elimination of our tracking stock structure.

(7)

For all periods except Q3-03, includes the dilutive effect of options, stock purchase rights and warrants allocated to Genzyme General but excludes the dilutive effect of the assumed conversion of the convertible subordinated notes and debentures allocated to Genzyme General because the conditions for conversion had not been met.

(8)

In Q3-03, excludes: (i) the dilutive effect of options, stock purchase rights and warrants to purchase shares of Genzyme General Stock because the effect would be anti-dilutive due to the net loss for the period; and (ii) the potentially dilutive effect of the assumed conversion of the convertible subordinated notes and debentures allocated to Genzyme General because the conditions for conversion had not been met.

(9)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating assets and liabilities to Genzyme Biosurgery and Genzyme Molecular Oncology. From that date forward, all of our assets and liabilities are allocated to Genzyme General.

13

GENZYME GENERAL (GENZ)
Consolidated Statements of Operations
(Unaudited, amounts in thousands, except per share amounts)

			Three Months Ended June 30,						Six Months Ended June 30,
			2004(1)			2003(1)			2004(1)			2003(1)
Total revenues			$	549,588		$	347,663		$	1,040,839		$	661,708
Operating costs and expenses:
	Cost of products and services sold			142,868			91,674			269,830			174,714
	Selling, general and administrative			152,850			95,203			296,070			180,449
	Research and development			99,370			58,834			192,186			115,163
	Amortization of intangibles			27,245			9,873			53,490			19,609
		Total operating costs and expenses		422,333			255,584			811,576			489,935
Operating income				127,255			92,079			229,263			171,773
Other income (expenses):
	Equity in loss of equity method investments			(4,274	)		(4,804	)		(8,105	)		(8,998	)
	Gain (loss) on investments in equity securities			71			(3,620	)		424			(3,620	)
	Minority interest			964			—			2,126			—
	Other			(390	)		774			(714	)		1,554
	Investment income			5,603			12,058			13,279			23,339
	Interest expense(2)			(17,495	)		(4,328	)		(27,821	)		(8,605	)
		Total other income (expenses)		(15,521	)		80			(20,811	)		3,670
Income before income taxes				111,734			92,159			208,452			175,443
Provision for income taxes				(33,558	)		(29,378	)		(62,382	)		(54,869	)
Net income			$	78,176		$	62,781		$	146,070		$	120,574
Allocated to Genzyme General Stock(3):
	Net income		$	78,176		$	62,781		$	146,070		$	120,574
	Tax benefit allocated from Genzyme Biosurgery			—			6,398			—			8,720
	Tax benefit allocated from Genzyme Molecular Oncology			—			1,657			—			3,420
	Net income allocated to Genzyme General Stock		$	78,176		$	70,836		$	146,070		$	132,714
	Net income per share of Genzyme General Stock:
		Basic	$	0.35		$	0.33		$	0.65		$	0.62
		Diluted(4)	$	0.34		$	0.32		$	0.63		$	0.60
	Weighted average shares outstanding:
		Basic		226,578			216,313			226,145			215,702
		Diluted(4)		231,544			222,867			231,731			221,650

(1)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating earnings to Genzyme Biosurgery and Genzyme Molecular Oncology. From that date forward, all of our earnings are allocated to Genzyme General. Earnings or losses allocated to Genzyme Biosurgery and Genzyme Molecular Oncology prior to July 1, 2003 remain allocated to those divisions and are not affected by the elimination of our tracking stock structure.

(2)

In June 2004, we completed the redemption of our 3% convertible subordinated debentures for cash, including $575.0 million in principal, accrued interest of approximately $0.8 million and $4.3 million in premium. Interest expense for the three and six months ended June 30, 2004 includes charges of $4.3 million for the premium paid upon redemption and $5.3 million to write off the unamortized debt fees associated with these debentures.

(3)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating earnings to Biosurgery Stock and Molecular Oncology Stock. From that date forward, all of our earnings are allocated to Genzyme General Stock. Earnings or losses allocated to Biosurgery Stock and Molecular Oncology Stock prior to July 1, 2003 remain allocated to those stocks and are not affected by the elimination of our tracking stock structure.

(4)

Net income per share on a diluted basis and weighted average shares-diluted for all periods include the dilutive effect of options, stock purchase rights and warrants to purchase shares of Genzyme General Stock, but exclude the potentially dilutive effect of the assumed conversion of our convertible subordinated debentures and notes because the conditions for conversion had not been met.

14

GENZYME GENERAL (GENZ)
Condensed Consolidated Balance Sheets
(Unaudited, amounts in thousands)

		June 30, 2004 (1)		December 31, 2003 (1)
Cash and all marketable securities (2)		$	657,047	$	1,227,460
Other current assets			944,828		909,490
Property, plant and equipment, net			1,202,580		1,151,133
Intangibles, net			1,698,383		1,517,791
Other assets			201,885		198,654
	Total assets	$	4,704,723	$	5,004,528
Current liabilities		$	512,570	$	392,025
Noncurrent liabilities (2)			1,068,496		1,676,091
Stockholders' equity			3,123,657		2,936,412
	Total liabilities and stockholders' equity	$	4,704,723	$	5,004,528

(1)

Effective July 1, 2003, in connection with the elimination of our tracking stock structure, we ceased allocating assets and liabilities to Genzyme Biosurgery and Genzyme Molecular Oncology. From that date forward, all of our assets and liabilities are allocated to Genzyme General.

(2)

In June 2004, we completed the redemption of our 3% convertible subordinated debentures for cash, including $575.0 million in principal, accrued interest of approximately $0.8 million and $4.3 million in premium. Upon redemption, we also recorded a non-cash charge of $5.3 million to interest expense to write off the unamortized debt fees associated with these debentures.

15

GENZYME GENERAL RECONCILIATION OF GAAP TO NON-GAAP EARNINGS
Quarter Ended June 30, 2004
(Amounts in thousands, except per share data)

		NON-GAAP Before Gains (Charges) & Amortization			Sangstat Acquisition- Related Costs			Convert Premium			Convert Fees			Amortization			NON-GAAP Before Effect of FIN 46			Effect of FIN 46			GAAP As Reported
Income Statement Classification:
Cost of products and services sold		$	(141,817	)	$	(1,051	)										$	(142,868	)				$	(142,868	)
Selling, general and administrative		$	(152,779	)													$	(152,779	)	$	(71	)	$	(152,850	)
Research and development		$	(97,512	)													$	(97,512	)	$	(1,858	)	$	(99,370	)
Amortization of intangibles		$	—											$	(27,245	)	$	(27,245	)				$	(27,245	)
Equity in loss of equity method investments		$	(5,238	)													$	(5,238	)	$	964		$	(4,274	)
Minority interest		$	—														$	—		$	964		$	964
Investment income		$	5,602														$	5,602		$	1		$	5,603
Interest expense		$	(7,853	)				$	(4,313	)	$	(5,329	)				$	(17,495	)	$	—		$	(17,495	)
Summary:
Pretax profit		$	149,672		$	(1,051	)	$	(4,313	)	$	(5,329	)	$	(27,245	)	$	111,734		$	—		$	111,734
Provision for income taxes			(47,519	)		387			1,587			1,961			10,026		$	(33,558	)	$	—		$	(33,558	)
Net income allocated to Genzyme General Stock		$	102,153		$	(664	)	$	(2,726	)	$	(3,368	)	$	(17,219	)	$	78,176		$	—		$	78,176
Net income per share of Genzyme General Stock:
	Basic	$	0.45		$	(0.003	)	$	(0.012	)	$	(0.014	)	$	(0.076	)	$	0.35		$	—		$	0.35
	Diluted	$	0.44		$	(0.003	)	$	(0.012	)	$	(0.015	)	$	(0.074	)	$	0.34		$	—		$	0.34
Weighted average shares outstanding:
	Basic		226,578			226,578			226,578			226,578			226,578			226,578			226,578			226,578
	Diluted		231,544			231,544			231,544			231,544			231,544			231,544			231,544			231,544

16

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Exhibit 99.1