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Exhibit 99.1

FINAL

For Immediate Release
April 16, 2003 Media Contact:
Bo Piela
617-252-7785 Investor Contact:
Sally Curley
617-591-7140

Genzyme General Reports 30 Percent Increase in First-Quarter Revenues

        CAMBRIDGE, MA—Genzyme Corp. today announced first-quarter financial results for its Genzyme General division (Nasdaq: GENZ). Revenues for the quarter rose 30 percent to $314.0 million, compared to $242.1 million for the same period last year.

        Reported net income allocated to Genzyme General stock was $61.9 million, or $.28 per diluted share, approximately double net income of $30.7 million, or $.14 per diluted share, recorded for the first quarter a year ago. Excluding amortization of $9.7 million, or $.03 per share, net income increased 49 percent to $68.0 million, or $.31 per diluted share, compared with $45.5 million, or $.21 per diluted share, prior to amortization and special items in the first quarter of last year.

        The effective net tax rate allocated to Genzyme General in the first quarter was 26 percent, and was 27 percent excluding amortization. Genzyme General ended the first quarter with approximately $1.2 billion in cash and equivalents.

        Selling, general and administrative expenses in the quarter were $85.2 million, in line with Genzyme's expectations and reflective of ongoing global activities to expand the markets for Fabrazyme® (agalsidase beta) and Renagel® (sevelamer hydrochloride).

        "We had a very strong quarter and are pleased that all of our businesses are focused and moving forward," said Henri A. Termeer, chairman and chief executive officer of Genzyme Corporation. "Our Renagel franchise is on track, with end-user demand driving solid growth in product sales. We are also generating excellent growth and momentum within our therapeutics franchise, which we expect will continue with product launches in a number of major markets during the second half of this year."

Guidance Update

        Earnings allocated to Genzyme General stock in the second quarter of 2003 are expected to be in the range of $.28-$.30 per diluted share. Excluding anticipated amortization of approximately $9.7 million, or $.03 per diluted share, taxed at the 36 percent corporate rate, earnings for the quarter are expected to be in the range of $.31-$.33 per share.

        For the year, earnings allocated to Genzyme General stock are expected to be in the range of $1.14-$1.24 per diluted share. Genzyme General confirmed its full-year 2003 earnings guidance of $1.25-$1.35 per diluted share, excluding amortization of approximately $39 million, or $.11 per diluted share, taxed at the 36 percent corporate rate.

        Genzyme General anticipates that it will end the year with approximately 221 million shares outstanding, including approximately 1.7 million new shares created during the second half of this year upon the exercise of long-term management retention stock options scheduled to expire on December 8, 2003, and January 7, 2004. These options were issued in 1993 and vest on June 30 of this year.

Business Update

        First-quarter sales of Renagel® (sevelamer hydrochloride), a phosphate binder for patients with end-stage renal disease on hemodialysis, were $58.8 million, nearly double sales of $29.5 million recorded for the first quarter last year when Genzyme began its program to reduce product inventory at U.S. wholesalers. Included in this total is $3.0 million in sales of bulk sevelamer to Chugai

Pharmaceutical Co. Ltd. at margins well below finished product margins. Inventory levels at U.S. wholesalers remain at the 4-5 week level.

        End-user demand for Renagel in the United States continues to be solid. In addition, the global introduction of Renagel is making good progress. During the first quarter, Genzyme obtained reimbursement approval for 800 mg Renagel tablets in France, the last major European market where this most popular form of the product was unavailable. It also began receiving orders from state governments in Brazil, one of the larger markets for the product outside the United States and Europe. In Japan, Renagel is scheduled for launch around the end of the second quarter. Chugai Pharmaceutical and Kirin Brewery Co. Ltd. are commercializing Renagel in Japan, and Genzyme will continue to sell them bulk sevelamer for tableting and will receive royalties on finished product sales.

        On March 25, Genzyme began shipping Renagel tablets to the European market from its new cGMP manufacturing facility in Waterford, Ireland, following the approval of Renagel production at the plant by the European Medicines Evaluation Agency. The FDA is expected to approve Renagel production at the plant around mid-year.

        Genzyme continues to support a range of clinical research in the field of renal disease. The largest study it is sponsoring is the Dialysis Clinical Outcomes Revisited (D-COR^SM) trial, comparing morbidity and mortality outcomes for patients receiving Renagel and those receiving calcium-based phosphate binders. The protocol for this study, which began in November 2001, required an interim analysis by a data monitoring board composed of independent physicians and biostatisticians. This analysis was performed recently on the first twelve months of data. The board found that the study's aggregate mortality rate was lower than anticipated and, to increase the possibility of demonstrating a statistically significant difference in mortality between the trial's treatment groups, it recommended that Genzyme extend the duration of treatment from the end of 2003 to the end of 2004. Genzyme has accepted this recommendation and now anticipates reporting results from this study in mid-2005. No data was provided to Genzyme on either morbidity or mortality.

        Sales of Cerezyme® (imiglucerase for injection), used in enzyme replacement therapy for patients with Type 1 Gaucher disease, grew 13 percent to $167.2 million, up from $148.1 million in the first quarter of last year. Genzyme continues to introduce Cerezyme in new markets throughout the world. It recently began selling the product in Russia, a potentially significant market given the size of the population.

        Sales of Fabrazyme® (agalsidase beta), an enzyme replacement therapy for patients with Fabry disease, were $11.8 million in the first quarter, nearly three times greater than sales of $4.0 million in the same quarter a year ago. Fabrazyme is now approved in 27 countries. In the United States, Genzyme expects the FDA to take action on the biologics license application for Fabrazyme by April 24. The agency had previously identified April 23 as the PDUFA date for the submission, but recently corrected its error. In Japan, Genzyme expects to receive approval for Fabrazyme during the second half of this year.

        Revenues from the sales of diagnostic products and services increased 16 percent to $47.7 million, compared to $41.0 million for same period a year ago. Genzyme's genetic testing business had a strong quarter, with 53 percent growth in cystic fibrosis testing volumes and 41 percent growth in overall DNA testing volumes. The unit introduced three new hematology/oncology cancer tests in the first quarter.

        Revenues from other products and services—including Thyrogen® (thyrotropin alfa for injection), WelChol® (colesevelam hydrochloride) and pharmaceutical intermediates—rose 47 percent to $28.5 million in the first quarter, compared to $19.5 million for the same quarter last year.

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Near-Term Pipeline Update

        Genzyme and partner BioMarin Pharmaceutical Inc. expect the FDA to take action on the biologics license application for Aldurazyme® (laronidase) by April 30, the official PDUFA date. They have submitted information related to post-marketing commitments and product labeling that the agency requested in its complete response letter of January 28. In addition, the inspection process for the Aldurazyme manufacturing facility has been completed. The companies are seeking to market Aldurazyme for the treatment of MPS I, a rare, progressive, and debilitating genetic disorder. They recently established a global patient registry as part of broad-ranging preparations in anticipation of product launch.

        The companies expect European Commission action on their marketing application for Aldurazyme in the next two months, following the issuance of a positive opinion by the Committee for Proprietary Medicinal Products on February 21. The CPMP opinion, while not binding on the commission, is the final step before formal approval to market Aldurazyme in the 15 countries of the European Union can be granted.

        Genzyme has begun patient enrollment in the first of two clinical studies planned for this year evaluating the use of its Myozyme™ recombinant human alpha-Glucosidase for Pompe disease. This study will include up to 16 children between the ages of six months and three years with the infantile-onset form of the disease, in which symptoms manifest themselves during the first year of life. A second study in infants less than six months of age is planned to begin this spring. Genzyme expects to complete enrollment in both studies this year, and plans to seek product registrations globally based on results from these trials and prior studies of enzyme replacement therapy for Pompe disease.

        Genzyme General develops and markets therapeutic products and diagnostic products and services. Genzyme General has five therapeutic products on the market, and a strong pipeline of therapeutic products in development focused on the treatment of genetic disorders and other chronic debilitating diseases with well-defined patient populations. Genzyme General is a division of the biotechnology company Genzyme Corporation.

        This press release contains forward-looking statements, including statements about: expectations concerning product launches; Genzyme General's anticipated financial results for the second quarter of 2003 and the full year, including earnings per share, amortization, tax rate, shares outstanding and stock option exercises; the expected timing of marketing approvals and launch of Renagel and Fabrazyme in Japan; the continued supply of bulk sevelamer to Chugai and Kirin and the anticipated receipt of royalties; the anticipated timing of FDA approval of Renagel production in facilities in Ireland; the expected timing of results from the DCOR trial and the anticipated impact of the extension of the trial; beliefs concerning the significance of certain product markets; the expected timing of regulatory responses or actions in the United States and Europe on marketing applications for Fabrazyme and Aldurazyme; the expected timing and design of clinical trials for Myozyme; and plans regarding regulatory submissions for Myozyme. These statements are subject to risks and uncertainties that could cause actual results to differ materially from those projected in these forward-looking statements. These risks and uncertainties include, among others: Genzyme General's actual results of operations for the second quarter of 2003 and the full year; the accuracy of Genzyme General's expectations concerning Renagel wholesaler inventory levels; whether end-user growth of Renagel is achieved in a manner consistent with Genzyme General's assumptions; compliance levels with Renagel wholesaler inventory management arrangements; the accuracy of estimates concerning the payor mix for Renagel; the timing and impact of the publication of KDOQI guidelines; the ability to improve patient compliance and optimize dosing of Renagel; the actual timing and results of clinical trials, including the DCOR trial; the actual impact of the CPMP opinion regarding Aldurazyme on the final decision by the European Commission; the FDA's response to the additional information submitted pursuant to the complete response letter for Aldurazyme; the actual timing and content of

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submissions to and decisions made by regulatory authorities in the U.S., Europe and Japan regarding facilities and marketing applications for Fabrazyme, Aldurazyme, Renagel and other products; the impact, if any, of war and terrorist activities on the operations and activities of Genzyme Corporation and third parties, including regulatory authorities; the ability to manufacture sufficient quantities of products for development and commercialization activities and to do so in a timely and cost efficient manner; the scope, validity and enforceability of patents and other proprietary rights held by third parties and the actual impact of such patents and other rights, if any, on our ability to commercialize products; our ability to obtain and maintain agreements with sublicensees, distributors and fill/finish facilities; the continued operation and funding of our joint venture with BioMarin; the availability and extent of reimbursement from third-party payers for Genzyme General's products and services; the accuracy of Genzyme General's information concerning the markets for its products and services and the competitive environment; and the risks and uncertainties described in reports filed by Genzyme Corporation with the Securities and Exchange Commission under the Securities Exchange Act of 1934, as amended, including without limitation Exhibit 99.2 to Genzyme's 2002 Annual Report on Form 10-K. Genzyme General Division common stock is a series of common stock of Genzyme Corporation. Therefore, holders of Genzyme General Division common stock are subject to all of the risks and uncertainties described in the those reports. We caution investors not to place undue reliance on the forward-looking statements contained in this press release. These statements speak only as of the date of this press release, and we undertake no obligation to update or revise the statements.

        Genzyme®, Cerezyme®, Fabrazyme® and Thyrogen® are registered trademarks of Genzyme Corporation. Renagel® is a registered trademark and DCOR^SM is a service mark of GelTex Pharmaceuticals, Inc. Welchol™ is a trademark of Sankyo Pharma Inc. Aldurazyme® is a registered trademark of BioMarin/Genzyme LLC. All rights reserved.

# # #

Conference Call Information

        There will be a conference call today at 11:00 a.m. ET to discuss Genzyme General's first quarter 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 1:30 p.m. ET through midnight on April 23 by dialing 719-457-0820. Please refer to reservation number 202390. This call will also be webcast live at http://www.genzyme.com/corp/investors/events_home.asp

Upcoming Events

        Genzyme Corp. will report second-quarter 2003 financial results on July 16 for its three divisions. If you would like to participate in any of these calls, please dial 719-457-2642 at 11:00 a.m. for Genzyme General, at 1:00 p.m. for Genzyme Molecular Oncology, and 3:00 p.m. for Genzyme Biosurgery. No passcode is necessary. Please refer to www.genzyme.com one week prior to the financial reporting date for any updates to this information. These calls will also be webcast live at http://www.genzyme.com/corp/investors/events_home.asp

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GENZYME GENERAL (A Division of Genzyme Corporation)

Combined Statements of Operations

(Unaudited, amounts in thousands, except per share amounts)

			Three Months Ended March 31,
			2003			2002
Total revenues			$	314,045		$	242,147
Operating costs and expenses:
	Cost of products and services sold			83,040			59,465
	Selling, general and administrative			85,246			76,390
	Research and development			56,329			63,836
	Amortization of intangibles			9,736			9,718
		Total operating costs and expenses		234,351			209,409
Operating income				79,694			32,738
Other income (expenses):
	Equity in net loss of unconsolidated affiliates			(4,194	)		(4,094	)
	Gain on investments in equity securities			—			166
	Other			780			(897	)
	Investment income			11,281			12,952
	Interest expense			(4,277	)		(4,541	)
		Total other income (expenses)		3,590			3,586
Income before income taxes				83,284			36,324
Provision for income taxes				(25,491	)		(12,015	)
Division net income				57,793			24,309
Allocated tax benefits (1)				4,085			6,429
Net income allocated to Genzyme General Stock			$	61,878		$	30,738
Net income per share of Genzyme General Stock:
	Basic		$	0.29		$	0.14
	Diluted (2)		$	0.28		$	0.14
Weighted average shares outstanding:
	Basic			215,091			213,332
	Diluted (2)			220,432			221,064

(1)

Represents tax benefits allocated from Genzyme Biosurgery and Genzyme Molecular Oncology to Genzyme General.

(2)

Net income per share allocated to Genzyme General Stock on a diluted basis and weighted average shares-diluted for both periods presented includes the dilutive effect of options, stock purchase rights and warrants, but excludes the effect of the convertible subordinated debentures allocated to Genzyme General as the effect would be anti-dilutive in each period.

Condensed Combined Balance Sheets
(Unaudited, amounts in thousands)

		March 31, 2003		December 31, 2002
Cash and all marketable securities		$	1,205,571	$	1,149,145
Other current assets			643,290		633,501
Property, plant and equipment, net			779,199		749,840
Intangibles, net			923,640		933,360
Other assets			98,689		89,955
	Total assets	$	3,650,389	$	3,555,801
Current liabilities		$	280,779	$	274,872
Noncurrent liabilities			692,436		695,045
Division equity			2,677,174		2,585,884
	Total liabilities and division equity	$	3,650,389	$	3,555,801

Genzyme General (A Division of Genzyme Corporation)
Analyst Schedule
(Unaudited, amounts in thousands, except percentage and per share amounts)

			Q1-02			Q2-02			Q3-02			Q4-02			Q1-03			Q1-03 vs. Q1-02 % B/(W)		FY 2001			FY 2002			YTD 3/31/03
Product and service revenue:
	Cerezyme and Ceredase		$	148,066		$	154,717		$	157,471		$	158,930		$	167,187		13	%	$	569,887		$	619,184		$	167,187
	Renagel			29,532			39,543			36,954			50,835			58,766		99	%		176,921			156,864			58,766
	Diagnostic Products and Services			41,059			43,111			43,241			45,399			47,698		16	%		151,045			172,810			47,698
	Other			20,981			27,805			34,335			42,033			39,843		90	%		74,934			125,154			39,843
		Total product and service revenue		239,638			265,176			272,001			297,197			313,494		31	%		972,787			1,074,012			313,494
R&D revenue				2,509			1,992			822			850			551		(78	%)		9,139			6,173			551
	Total revenues			242,147			267,168			272,823			298,047			314,045		30	%		981,926			1,080,185			314,045
Total product and service gross profit				180,173			201,557			206,504			219,960			230,454		28	%		735,445			808,194			230,454
SG&A expense				76,390			80,519			86,221			80,553			85,246		(12	%)		295,068			323,683			85,246
R&D expense				63,836			56,477			54,407			55,323			56,329		12	%		187,502			230,043			56,329
Amortization of intangibles				9,718			9,723			9,814			9,743			9,736		(0	%)		74,296			38,998			9,736
IPR&D				—			—			—			—			—		—			95,568			—			—
Charge for impaired assets				—			—			—			13,986			—		—			—			13,986			—
Operating profit				32,738			56,830			56,884			61,205			79,694		143	%		92,150			207,657			79,694
Other income (expenses):
	Equity in net loss of unconsolidated affiliates			(4,094	)		(3,948	)		(2,387	)		(6,429	)		(4,194	)	(2	%)		(34,365	)		(16,858	)		(4,194	)
	Gain (loss) on investments in equity securities			166			343			29			(15,035	)		—		(100	%)		(25,996	)		(14,497	)		—
	Minority interest			—			—			—			—			—		—			2,259			—			—
	Other			(897	)		1,749			(274	)		(730	)		780		187	%		(2,117	)		(152	)		780
	Investment income			12,952			12,079			12,430			11,483			11,281		(13	%)		47,806			48,944			11,281
	Interest expense			(4,541	)		(4,678	)		(4,258	)		(4,370	)		(4,277	)	6	%		(23,192	)		(17,847	)		(4,277	)
Profit before income taxes				36,324			62,375			62,424			46,124			83,284		129	%		56,545			207,247			83,284
Tax provision				(12,015	)		(17,964	)		(17,906	)		(8,631	)		(25,491	)	(112	%)		(52,666	)		(56,516	)		(25,491	)
Division net income				24,309			44,411			44,518			37,493			57,793		138	%		3,879			150,731			57,793
Cumulative effect of change in accounting for derivative financial instruments, net of tax (1)				—			—			—			—			—		—			4,167			—			—
Division net income before allocated tax benefits				24,309			44,411			44,518			37,493			57,793		138	%		8,046			150,731			57,793
Allocated tax benefits				6,429			5,229			8,898			7,239			4,085		(36	%)		36,497			27,795			4,085
Net income allocated to Genzyme General Stock			$	30,738		$	49,640		$	53,416		$	44,732		$	61,878		101	%	$	44,543		$	178,526		$	61,878
Net income per share of Genzyme General Stock—diluted (2)			$	0.14		$	0.23		$	0.25		$	0.20		$	0.28		100	%	$	0.21		$	0.81		$	0.28
Weighted average shares outstanding—diluted (4)				221,064			219,634			217,541			219,313			220,432		0	%		211,176			219,388			220,432

Notes:

(1)

On January 1, 2002, we adopted SFAS No. 133, "Accounting for Derviative Financial Instruments and Hedging Activities," as amended by SFAS No. 137 and SFAS No. 138. In accordance with the transition provisions of SFAS No. 133, Genzyme General recorded a cumulative adjustment of $4.1 million, net of tax, in its combined statements of operations for the year ended December 31, 2001 to recognize the fair value of warrants to purchase shares of GTC Biotherapeutics, Inc. (formerly Genzyme Transgenics Corporation) common stock held on January 1, 2001.

(2)

For all periods except 2001, includes the dilutive effect of options, stock purchase rights and warrants allocated to Genzyme General but excludes the dilutive effect of the convertible subordinated debentures allocated to Genzyme General because the effect in each period would be anti-dilutive.

(3)

In 2001, includes the dilutive effect of options, warrants and the convertible subordinated debentures and notes allocated to Genzyme General.

(4)

All weighted average shares data reflect the 2 for 1 split of Genzyme General Stock on June 1, 2001.

Genzyme General (A Division of Genzyme Corporation)
Analyst Schedule
(Unaudited, amounts in thousands, except percentage amounts)

		Q1-02			Q2-02			Q3-02			Q4-02			Q1-03			FY 2001			FY 2002			YTD 3/31/03
Total revenues		$	242,147		$	267,168		$	272,823		$	298,047		$	314,045		$	981,926		$	1,080,185		$	314,045
As a % of total product and service revenue:
	Cerezyme and Ceredase		62	%		58	%		58	%		54	%		53	%		59	%		58	%		53	%
	Renagel		12	%		15	%		13	%		17	%		19	%		18	%		14	%		19	%
	Diagnostic Products and Services		17	%		16	%		16	%		15	%		15	%		15	%		16	%		15	%
	Other		9	%		11	%		13	%		14	%		13	%		8	%		12	%		13	%
Total product and service gross margin			75	%		76	%		76	%		74	%		74	%		76	%		75	%		74	%
SG&A expense as % of total revenue			32	%		30	%		32	%		27	%		27	%		30	%		30	%		27	%
R&D expense as % of total revenue			26	%		21	%		20	%		19	%		18	%		19	%		21	%		18	%
Operating profit as % of total revenue			14	%		21	%		21	%		21	%		25	%		9	%		19	%		25	%
Tax provision (benefit) as % of profit before tax			15	%		20	%		14	%		3	%		26	%		29	%		14	%		26	%

		Q1-02		Q2-02		Q3-02		Q4-02		Q1-03		FY 2001		FY 2002		Q1-03
Other selected financial data:
	Cash and all marketable securities	$	1,060,771	$	1,080,332	$	1,121,022	$	1,149,145	$	1,205,571	$	1,041,500	$	1,149,145	$	1,205,571
	Working capital		605,317		638,283		680,873		825,573		848,955		473,870		825,573		848,955
	Property, plant & equipment, net		609,275		663,220		704,579		749,840		779,199		581,401		749,840		779,199
	Goodwill and other intangible assets		972,544		963,248		954,051		933,360		923,640		981,468		933,360		923,640
	Total assets		3,236,540		3,348,856		3,418,299		3,555,801		3,650,389		3,225,254		3,555,801		3,650,389
	Long-term debt, convertible notes and long-term capital leases		600,045		600,044		600,040		600,038		600,026		600,085		600,038		600,026
	Division equity		2,326,273		2,431,852		2,491,892		2,585,884		2,677,174		2,280,352		2,585,884		2,677,174

GENZYME GENERAL

RECONCILIATION OF GAAP TO NON-GAAP EARNINGS

Quarter Ended March 31, 2003

(Amounts in thousands, except per share data)

		NON-GAAP Before Amortization			Amortization			GAAP As Reported
Income Statement Classification:
Amortization of intangibles		$	—		$	(9,736	)	$	(9,736	)
Summary:
Pretax profit		$	93,020		$	(9,736	)	$	83,284
Provision for income taxes			(24,989	)		3,583			(21,406	)
Net income allocated to Genzyme General Stock		$	68,031		$	(6,153	)	$	61,878
Net income per share of Genzyme General Stock:
	Basic	$	0.32		$	(0.03	)	$	0.29
	Diluted	$	0.31		$	(0.03	)	$	0.28
Weighted average shares outstanding:
	Basic		215,091			215,091			215,091
	Diluted		220,432			220,432			220,432

GENZYME GENERAL

RECONCILIATION OF GAAP TO NON-GAAP EARNINGS

Quarter Ended March 31, 2002

(Amounts in thousands, except per share data)

		NON-GAAP Before Gains (Charges) & Amortization			Novazyme Restructuring			Diagnostics Restructuring			Pompe CHO/Synpac Program			Amortization			GAAP As Reported
Income Statement Classification:
Gross margin		$	183,028					$	(2,856	)							$	180,172
Research and development expense		$	(53,082	)	$	(1,968	)				$	(8,786	)				$	(63,836	)
Amortization of intangibles		$	—											$	(9,718	)	$	(9,718	)
Summary:
Pretax profit		$	59,652		$	(1,968	)	$	(2,856	)	$	(8,786	)	$	(9,718	)	$	36,324
Provision for income taxes			(14,170	)		724			1,051			3,233			3,576			(5,586	)
Net income allocated to Genzyme General Stock		$	45,482		$	(1,244	)	$	(1,805	)	$	(5,553	)	$	(6,142	)	$	30,738
Net income per share of Genzyme General Stock:
	Basic	$	0.21		$	(0.006	)	$	(0.008	)	$	(0.026	)	$	(0.029	)	$	0.14
	Diluted	$	0.21		$	(0.006	)	$	(0.008	)	$	(0.025	)	$	(0.028	)	$	0.14
Weighted average shares outstanding:
	Basic		213,332			213,332			213,332			213,332			213,332			213,332
	Diluted		221,064			221,064			221,064			221,064			221,064			221,064

GENZYME CORPORATION

Consolidated Statements of Operations

(Unaudited, amounts in thousands, except per share amounts)

				Three Months Ended March 31,
				2003			2002
Total revenues				$	381,859		$	297,940
Operating costs and expenses:
	Cost of products and services sold				111,812			87,172
	Selling, general and administrative				114,224			102,958
	Research and development				75,631			82,141
	Amortization of intangibles				17,505			17,597
			Total operating costs and expenses		319,172			289,868
Operating income					62,687			8,072
Other income (expenses):
	Equity in net loss of unconsolidated affiliates				(4,194	)		(4,094	)
	Gain on investments in equity securities				—			166
	Other				750			(864	)
	Investment income				11,614			13,437
	Interest expense				(6,490	)		(6,806	)
			Total other income (expenses)		1,680			1,839
Income before income taxes					64,367			9,911
Provision income taxes					(18,998	)		(3,138	)
Net income (loss) before cumulative effect of change in accounting for goodwill					45,369			6,773
Cumulative effect of change in accounting for goodwill (1)					—			(98,270	)
Net income (loss) (1)				$	45,369		$	(91,497	)
Net income (loss) per share:
	Allocated to Genzyme General Stock:
		Genzyme General division net income		$	57,793		$	24,309
		Tax benefit allocated from Genzyme Biosurgery			2,322			4,299
		Tax benefit allocated from Genzyme Molecular Oncology			1,763			2,130
		Net income allocated to Genzyme General Stock		$	61,878		$	30,738
		Net income per share of Genzyme General Stock:
			Basic	$	0.29		$	0.14
			Diluted (2)	$	0.28		$	0.14
		Weighted average shares outstanding:
			Basic		215,091			213,332
			Diluted (2)		220,432			221,064
Allocated to Biosurgery Stock:
	Genzyme Biosurgery net loss before cumulative effect of change in accounting for goodwill			$	(14,102	)	$	(20,382	)
	Cumulative effect of change in accounting for goodwill (1)				—			(98,270	)
	Genzyme Biosurgery division net loss				(14,102	)		(118,652	)
	Allocated tax benefit				2,408			2,448
	Net loss allocated to Biosurgery Stock (1)			$	(11,694	)	$	(116,204	)
	Net loss per share of Biosurgery Stock—basic and diluted:
		Net loss per share before cumulative effect of change in accounting for goodwill		$	(0.29	)	$	(0.46	)
		Per share cumulative effect of change in accounting for goodwill (1)			—			(2.48	)
	Net loss per share of Biosurgery Stock—basic and diluted (1)			$	(0.29	)	$	(2.94	)
		Weighted average shares outstanding			40,578			39,564
Allocated to Molecular Oncology Stock:
	Net loss			$	(4,815	)	$	(6,031	)
	Net loss per share of Molecular Oncology Stock-basic and diluted			$	(0.28	)	$	(0.36	)
	Weighted average shares outstanding				16,939			16,763

(1)

Effective January 1, 2002, in connection with the provisions of SFAS No. 142, "Goodwill and Other Intangible Assets," we ceased amortizing goodwill. In connection with the adoption of SFAS No. 142, we tested the goodwill of our cardiothoracic reporting unit for impairment and, as a result, reduced goodwill by recording a cumulative effect impairment charge of $98.3 million in our consolidated statements of operations and the combined statements of operations of Genzyme Biosurgery for the three months ended March 31, 2002.

(2)

Net income per share allocated to Genzyme General Stock on a diluted basis and weighted average shares-diluted for both periods presented includes the dilutive effect of options, stock purchase rights and warrants, but excludes the effect of the convertible subordinated debentures allocated to Genzyme General as the effect would be anti-dilutive in each period.

GENZYME CORPORATION

Condensed Consolidated Balance Sheets

(Unaudited, amounts in thousands)

		March 31, 2003		December 31, 2002
Cash and all marketable securities		$	1,234,318	$	1,195,004
Other current assets			693,277		676,231
Property, plant and equipment, net			831,040		802,448
Intangibles, net			1,309,049		1,326,553
Other assets			93,115		82,813
	Total assets	$	4,160,799	$	4,083,049
Current liabilities		$	616,028	$	607,800
Noncurrent liabilities			770,703		777,402
Stockholders' equity			2,774,068		2,697,847
	Total liabilities and stockholders' equity	$	4,160,799	$	4,083,049

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Exhibit 99.1

Genzyme General Reports 30 Percent Increase in First-Quarter Revenues
Conference Call Information
Upcoming Events
GENZYME GENERAL (A Division of Genzyme Corporation) Combined Statements of Operations (Unaudited, amounts in thousands, except per share amounts)
Condensed Combined Balance Sheets (Unaudited, amounts in thousands)
GENZYME GENERAL RECONCILIATION OF GAAP TO NON-GAAP EARNINGS Quarter Ended March 31, 2003 (Amounts in thousands, except per share data)
GENZYME GENERAL RECONCILIATION OF GAAP TO NON-GAAP EARNINGS Quarter Ended March 31, 2002 (Amounts in thousands, except per share data)
GENZYME CORPORATION Consolidated Statements of Operations (Unaudited, amounts in thousands, except per share amounts)
GENZYME CORPORATION Condensed Consolidated Balance Sheets (Unaudited, amounts in thousands)