Exhibit 99.1

For Immediate Release	Media Contact:	Investor Contact:
February 11, 2009	Erin Emlock	Patrick Flanigan
	(617) 768-6923	(617) 768-6563

Strong Fourth Quarter for Genzyme Concludes Productive Year

Non-GAAP EPS Reaches $1.04 in Fourth Quarter and $4.00 for 2008

Company Provides Confident Outlook for 2009

CAMBRIDGE, Mass. — Genzyme Corp. (NASDAQ: GENZ) today announced solid fourth-quarter revenue and earnings growth and provided guidance for 2009 that underscored its positive outlook for the year.

GAAP net income rose to $86.7 million, or $0.31 per diluted share, compared with $78.9 million, or $0.29 per diluted share, in the prior fourth quarter.  Non-GAAP net income increased 16 percent to $288.5 million compared with $249.2 million in the fourth quarter of 2007.  Non-GAAP earnings rose 14 percent to $1.04 per diluted share from $0.91 per diluted share in the same period in 2007.

GAAP figures for the quarter include a non refundable upfront fee to Osiris Therapeutics Inc. for a late-stage product candidate, amortization and stock compensation expenses, and a charge to write off overhead and material associated with incomplete process validation runs at the company’s Belgium manufacturing facility.

“We had an excellent year last year and exceeded our earnings expectations despite the economic environment and the challenges we faced with Myozyme,” said Henri A. Termeer, Genzyme chairman and chief executive officer.  “We delivered on our

financial objectives but did not ignore our future.  We continued to expand and invest in our pipeline and now have seven exciting late-stage programs with the potential to sustain our growth over the long term.  Genzyme is stronger today than it was a year ago, and we feel confident about our future.”

As previously announced, fourth-quarter revenue rose 13 percent to $1.17 billion, reflecting an approximate $39 million negative impact of foreign exchange, compared with $1.04 billion in the same period in 2007.

Individual product sales for the fourth quarter and the year, along with expectations for the longer-term growth of Genzyme’s business segments, were detailed in a January 13, 2009, press release coinciding with the company’s presentation at the JPMorgan Healthcare Conference.

2008 Results

Total revenue in 2008 increased 21 percent to $4.6 billion from $3.8 billion in 2007.  GAAP net income was $421.1 million, or $1.50 per diluted share, compared with $480.2 million, or $1.74 per diluted share, in 2007.  Non-GAAP net income increased 18 percent to $1.1 billion, compared with $939.9 million in 2007.  Non-GAAP earnings increased 15 percent to $4.00 per diluted share from $3.47 in 2007.

Genzyme generated approximately $1.5 billion in cash predominantly from operations in 2008 and utilized this cash flow to substantially eliminate all debt, invest in its global infrastructure, repurchase shares, and complete strategic transactions that significantly strengthened its late-stage pipeline.

2

Financial Guidance for 2009

Earnings

·Genzyme is on-track to achieve its goal of 20 percent compound average non-GAAP earnings growth from 2006 — 2011.  Non-GAAP earnings are projected to rise to approximately $7.00 per diluted share by 2011.

·Non-GAAP earnings in 2009 are expected to increase to $4.70 per diluted share.  GAAP earnings, which include amortization and stock compensation expenses, are expected to reach $3.50 per diluted share.

·Non-GAAP earnings in the first quarter of 2009 are expected to be similar to earnings for the fourth quarter of 2008.  Genzyme anticipates that its non-GAAP earnings will accelerate starting in the second quarter, as two key regulatory approvals for Myozyme® (alglucosidase alfa) are secured: E.U. approval of Myozyme produced at the 4000 L scale, which will help provide the capacity to meet the strong global demand for the product; and U.S. approval of Myozyme produced at the 2000 L scale, which will be called Lumizyme™ (alglucosidase alfa), giving the company the ability to promote the Pompe disease therapy produced at this scale in the U.S. market.  Mozobil™ (plerixafor injection), which was launched last month, will also help drive earnings growth.

Revenue

·Revenue is expected to reach $5.2 — $5.4 billion in 2009.  This reflects an approximate $150 million unfavorable impact of foreign exchange.  Genzyme anticipates strong volume growth in all five of its business segments:

Total revenue for the Genetic Disease segment is expected to reach $2.47 — $2.53 billion this year, compared with $2.23 billion in 2008.

·Within this segment, Myozyme revenue is expected to increase to $430 — $440 million, compared with $296 million in 2008.  The company anticipates FDA action by February 28 on its filing for U.S. approval of Lumizyme.  European Commission approval of Myozyme produced at the 4000 L scale would be expected in April under the standard review procedure.  Genzyme has requested expedited review of its application.

·Revenue for Fabrazyme® (agalsidase beta), an important growth driver that is performing well in a competitive marketplace, is expected to rise to $560 — $570 million in 2009 from $494 million last year.

·Cerezyme® (imiglucerase for injection) revenue is expected to reach $1.25 — $1.28 billion, compared with $1.24 billion in 2008, reflecting its mature status and the impact of foreign exchange.

The Cardiometabolic and Renal segment’s total revenue is expected to increase to $1.04 — $1.07 billion this year, compared with $956 million in 2008.

3

·Within this segment, Genzyme’s sevelamer therapies, Renvela® (sevelamer carbonate) and Renagel® (sevelamer hydrochloride), are expected to produce revenues of $725 — $735 million in 2009, compared with $678 million last year.  Anticipated key drivers include E.U. approval of Renvela and the expansion of the product’s U.S. indication to include the treatment of patients with chronic kidney disease who are not on dialysis, both of which are expected in mid-2009.  Genzyme is working to transition all remaining U.S. Renagel patients to Renvela, with the goal of completing the transition by September 30, 2009.

Total revenue for the Biosurgery segment is expected to reach $540 — $570 million this year, compared with $491 million in 2008.

·FDA approval for Synvisc-One™ is expected soon, and the product is expected to be a significant growth driver for the franchise over the longer term.

The Hematologic Oncology segment’s total revenue is expected to rise to $185 — $210 million this year, compared with $117 million in 2008.

·Within this segment, Mozobil revenue in 2009 is expected to reach $40 — $50 million.  The launch of this treatment is going well, with broad adoption by transplant centers.  Mozobil was approved in the United States in December, and E.U. approval is expected in the second half of 2009.  Genzyme expects that the product will become an integral part of the treatment regimen for stem-cell transplantation because of the clinical and economic benefits it offers to patients, physicians and transplant centers.

Other revenue is expected to reach $1.02 — $1.08 billion in 2009, compared with $814 million in 2008.

·This segment includes revenue from the company’s Genetics, Diagnostics, Transplant and Pharmaceuticals businesses, and other product revenue.

Gross Margin

·The non-GAAP gross margin for 2009 is expected to be approximately 75 percent of revenues, compared with 76 percent in 2008.  The gross margin reflects underutilized capacity at the two plants where larger scale production of Myozyme is starting to come online.  It also reflects changes in product mix.

Expenses

·Non-GAAP selling, general and administrative expenses are expected to represent approximately 26 percent of revenue in 2009, lower than SG&A expenses of 27 percent of revenue in 2008.  SG&A spending this year will reflect several major

4

product launches, including Mozobil in the United States and Europe and Synvisc-One™, Lumizyme, and Clolar®(clofarabine) for adult AML in the United States.

·Non-GAAP research and development spending is expected to represent approximately 16 percent of revenue in 2009, consistent as a percentage of revenue with R&D spending in 2008.  Genzyme continues to make a significant investment in its pipeline to sustain its future growth.  The company is currently conducting approximately 100 clinical trials.

Tax Rate

·Genzyme’s non-GAAP tax rate this year is expected to be approximately 29 percent.  The GAAP tax rate is expected to be 30 percent.

Capital Expenditures

·Capital expenditures are expected to total $600 — $650 million this year.  Genzyme continues to make a significant investment in manufacturing capacity to support the growth of existing products and prepare for the launch of products in late-stage development.  Construction is underway on two new manufacturing facilities: one for Thymoglobulin® (anti-thymocyte globulin, rabbit) in France, and one for cell culture production in Framingham, Mass.

Development Programs

Genzyme’s R&D pipeline includes seven major late-stage programs with the potential to sustain the company’s growth beyond 2011:

Clolar for adult AML

Genzyme has filed for FDA approval of Clolar as a first-line therapy for adult acute myeloid leukemia.  If this application receives priority review, Clolar could be approved for this indication in the first half of 2009.  An E.U. filing is anticipated in the second half of 2009, with approval expected in the first half of 2010.  Clolar is currently approved in the United States and Europe for the treatment of acute lymphoblastic leukemia in relapsed and refractory pediatric patients.

Alemtuzumab for multiple sclerosis

Genzyme continues to enroll patients in two phase 3 trials of alemtuzumab, which has the potential to become a new standard of care in the treatment of multiple sclerosis. Enrollment in the study involving previously untreated patients is expected to conclude by mid year, and enrollment in the study involving treatment-experienced patients is expected to conclude in the first half of next year.  The design of the latter study has been modified to eliminate its high-dose arm based on final phase 2 data showing that both the high and low doses of alemtuzumab were efficacious when compared to

5

interferon beta-1a.  Results for the treatment naïve study are expected in 2011, and Genzyme anticipates approval of alemtuzumab in 2012.

Mipomersen for high-risk hypercholesterolemia

Genzyme and Isis Pharmaceuticals Inc. formed a collaboration in 2008 to develop and commercialize the novel lipid-lowering drug mipomersen for patients with high cholesterol who are at high risk of cardiovascular disease.  The companies have begun three late-stage studies of mipomersen during the past year, and a fourth is currently screening patients.  The companies have also completed enrollment in a phase 3 trial involving patients with homozygous familial hypercholesterolemia.  Top-line data are expected in mid-2009.  The submission of a U.S. marketing application for this indication is anticipated during the second half of 2010, and the first approval is expected in 2011.  An outcome study is expected to begin by mid-2010.

Prochymal™ for graft vs. host disease and Crohn’s disease

Genzyme and Osiris Therapeutics Inc. formed a collaboration last year to develop and commercialize the adult stem cell treatment Prochymal.  Data from phase 3 studies of Prochymal in graft vs. host disease (GvHD) and Crohn’s disease are expected in 2009, and Osiris also expects to seek FDA approval for the GvHD indication this year.

GENZ-112638 for Gaucher disease

Genzyme is preparing to initiate two phase 3 studies of Genz-112638, a potential oral therapy for Gaucher disease, following the positive outcome of a recent meeting with the FDA to discuss study design.  Patient enrollment is expected to begin during the first half of the year.  Final results from the open-label phase 2 study will be presented February 20 at the Lysosomal Disease Network’s WORLD Symposium.

Ataluren for Duchenne muscular dystrophy

Genzyme and PTC Therapeutics Inc. formed a collaboration in 2008 to develop and commercialize ataluren (formerly known as PTC124), a novel oral therapy for the treatment of genetic disorders due to nonsense mutations, which is potentially applicable to hundreds of diseases.  A pivotal phase 2b trial of ataluren in Duchenne muscular dystrophy (DMD) is fully enrolled and results are expected next year.  A trial in cystic fibrosis (CF) is expected to begin during the first half of this year.

Other Key Programs

Genzyme expects to begin a pivotal trial of an advanced phosphate binder (APB) this year.  The APB is designed to more effectively bind phosphate for a substantial improvement in potency over existing therapies while maintaining all the benefits of sevelamer.  The company anticipates that the APB will be approved by the time the core patent estate for sevelamer expires in 2014.

6

During the first half of 2010, Genzyme expects to file an IND for a potential second-generation enzyme replacement therapy for Pompe disease that in preclinical studies to date has demonstrated a five-fold greater substrate clearance vs. alglucosidase alfa.

About Genzyme

One of the world’s leading biotechnology companies, Genzyme is dedicated to making a major positive impact on the lives of people with serious diseases.  Since 1981, the company has grown from a small start-up to a diversified enterprise with more than 11,000 employees in locations spanning the globe and 2008 revenues of $4.6 billion.  In 2007, Genzyme was chosen to receive the National Medal of Technology, the highest honor awarded by the President of the United States for technological innovation.

With many established products and services helping patients in approximately 100 countries, Genzyme is a leader in the effort to develop and apply the most advanced technologies in the life sciences.  The company’s products and services are focused on rare inherited disorders, kidney disease, orthopaedics, cancer, transplant and immune disease, and diagnostic testing.  Genzyme’s commitment to innovation continues today with a substantial development program focused on these fields, as well as cardiovascular disease, neurodegenerative diseases, and other areas of unmet medical need.

This press release contains forward-looking statements regarding Genzyme financial outlook and business plans and strategies, including without limitation: its anticipated compound average earnings growth rate from 2006-2011; its Q1 2009, YE 2009 and YE 2011 EPS guidance and drivers of EPS growth; its projected 2009 revenues for the company, for each business segment, for certain products, including Myozyme, Fabrazyme, Cerezyme, Renagel/Renvela, and Mozobil, and all other revenues, as well as the anticipated drivers of such revenue growth; the expected timing of receipt of regulatory approvals for alglucosidase alfa produced at the 2000L scale in the US and 4000L scale in the EU; its regulatory approval plans and timetables for existing products, including EU approval of Renvela, US approval of Renvela for use in CKD patients not on dialysis, EU approval of Mozobil, US approval of Synvisc-One, US and EU approval of Clolar for use in adult patients with AML, and US approval of alemtuzumab-MS; its plans and estimated timetables for new and next-generation product filings and approvals, including for mipomersen, Genz-112638, Prochymal, Ataluren, and APB; its projected 2009 non-GAAP gross margin, SG&A and R&D expenses as a percentage of revenues; its expected 2009 GAAP and non-GAAP tax rates; and its projected 2009 capital expenditures. These statements are subject to risks and uncertainties that could cause actual results to differ materially from those forecasted. These risks and uncertainties include, among others: the ability of Genzyme and its collaboration partners to successfully complete preclinical and clinical development of new products, including mipomersen, Prochymal, Genz-112638, and Ataluren; Genzyme’s ability to expand the use of current and next-generation products in existing and new indications, including Renvela, Synvisc-ONE, Mozobil, Clolar, alemtuzumab-MS and the APB;

7

Genzyme’s ability to obtain and maintain regulatory approvals for products and manufacturing facilities, including alglucosidase alfa produced at the 2000L and 4000L scales and the timing of receipt of such approvals; Genzyme’s ability to manufacture products and product candidates in a timely and cost effective manner and in sufficient quantities to meet demand; Genzyme’s ability to maintain and enforce intellectual property rights; Genzyme’s ability to successfully identify and market to new patients; the scope of third-party reimbursement coverage for Genzyme’s products and services; and the risks and uncertainties described in Genzyme’s SEC reports filed under the Securities Exchange Act of 1934, including the factors discussed under the caption “Risk Factors” in Genzyme’s Quarterly Report on Form 10-Q for the period ended September 30, 2008. Genzyme cautions investors not to place substantial reliance on the forward-looking statements contained in this press release. These statements speak only as of today’s date and Genzyme undertakes no obligation to update or revise the statements.

Genzyme®, Myozyme®, Fabrazyme®, Cerezyme®, Renagel®, Renvela®, Synvisc®, and Clolar® are registered trademarks and Mozobil™, Synvisc-One™ and Lumizyme™ are trademarks of Genzyme Corporation or its subsidiaries.  Prochymal™ is a trademark of Osiris Therapeutics Inc.  All rights reserved.

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 1-678-999-4572 outside the United States.

Conference Call Information

Genzyme will host a conference call today at 11:00 a.m. Eastern.   To participate in the call, please dial 773-799-3828 and refer to pass code “Genzyme.”  A replay of this call will be available by dialing 402-998-1342.  This call will also be Webcast live on the investor events section of www.genzyme.com.  Replays of the call and the Webcast will be available until midnight on February 18, 2009.

Upcoming Events

Genzyme will host a conference call on April 22 at 11: 00 a.m. Eastern to discuss financial results for the first quarter of 2009.  To participate in the call, please dial 773-799-3828 and refer to pass code “Genzyme.”  A replay of this call will be available by dialing 402-998-1342.  This call will also be Webcast live on the investor events section of www.genzyme.com.  Replays of the call and the Webcast will be available until midnight on April 29, 2009.

#     #     #

8

GENZYME CORPORATION (GENZ)

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

	Three Months Ended						Year Ended
	December 31,						December 31,
	2008			2007			2008			2007
Total revenues	$	1,173,560		$	1,036,758		$	4,605,039		$	3,813,519
Operating costs and expenses:
Cost of products and services sold	290,711			262,657			1,148,562			927,330
Selling, general and administrative	341,329			308,377			1,338,190			1,187,184
Research and development	358,430			197,323			1,308,330			737,685
Amortization of intangibles	59,884			51,804			226,442			201,105
Charge for impaired assets	2,036			—			2,036			—
Purchase of in-process research and development	—			106,350			—			106,350
Total operating costs and expenses	1,052,390			926,511			4,023,560			3,159,654
Operating income	121,170			110,247			581,479			653,865
Other income (expenses):
Equity in income of equity method investments	13			8,489			201			7,398
Minority interest	625			—			2,217			3,932
Gain (loss) on investments in equity securities, net	861			(969		)	(3,340		)	13,067
Other	(1,021		)	(747		)	(1,861		)	(637		)
Investment income	11,245			18,509			51,260			70,196
Interest expense	(822		)	(2,864		)	(4,418		)	(12,147		)
Total other income (expenses)	10,901			22,418			44,059			81,809
Income before income taxes	132,071			132,665			625,538			735,674
Provision for income taxes	(45,421		)	(53,766		)	(204,457		)	(255,481		)
Net income	$	86,650		$	78,899		$	421,081		$	480,193
Net income per share:
Basic	$	0.32		$	0.30		$	1.57		$	1.82
Diluted (1)	$	0.31		$	0.29		$	1.50		$	1.74
Weighted average shares outstanding:
Basic	270,658			265,418			268,490			263,895
Diluted (1)	284,338			283,374			285,595			280,767

All amounts herein are presented in accordance with GAAP and are provided for quantitative analysis only and should be read in conjunction with the text of the Earnings Release. In addition, Genzyme believes that certain non-GAAP financial measures, when considered together with the GAAP figures, can enhance the overall understanding of Genzyme’s past financial performance and its prospects for the future. Please refer to our GAAP to Non-GAAP Reconciliations attached to the Earnings Releases for the above respective periods, which are included in the Investors section of our website at www.genzyme.com. The non-GAAP financial measures are provided with the intent of providing investors with a more complete understanding of the trends underlying our operating results and financial position and are among the primary indicators Genzyme management uses for planning and forecasting purposes and measuring the company’s performance.

Please refer to our Form 10-Q’s and Form 10-K’s for an in-depth discussion and analysis of our results of operations and financial position and for detailed information regarding specific material transactions in a particular period.

(1)In accordance with EITF 04-8, the shares issuable upon conversion of our $690.0 million in principal of 1.25% convertible senior notes are included in diluted weighted average shares outstanding for purposes of computing diluted earnings per share, unless the effect would be anti-dilutive. The notes were redeemed for primarily cash on December 1, 2008. Accordingly, interest and debt fees related to these notes of $1.3 million and $1.9 million, net of tax, for the three months ended December 31, 2008 and 2007, respectively, and $6.9 million and $7.5 million, net of tax, for the years ended December 31, 2008 and 2007, respectively, have been added back to net income. Approximately 6.4 million shares and 8.9 million shares issuable upon conversion of these notes prior to redemption have been included in diluted weighted average shares outstanding for the three months ended and the year ended December 31, 2008, respectively. Approximately 9.7 million shares issuable upon conversion of these notes have been included in diluted weighted average shares outstanding for the same periods of 2007.

GENZYME CORPORATION (GENZ)
Condensed Consolidated Balance Sheets

(Unaudited, amounts in thousands)

	December 31,		December 31,
	2008		2007
Cash and all marketable securities	$	973,775	$	1,460,394
Other current assets	1,852,220		1,661,740
Property, plant and equipment, net	2,306,567		1,968,402
Intangibles, net (1)	3,285,298		2,959,480
Other noncurrent assets	518,764		251,725
Total assets	$	8,936,624	$	8,301,741
Current liabilities	$	914,265	$	1,502,406
Noncurrent liabilities (1)	687,163		186,398
Stockholders’ equity	7,335,196		6,612,937
Total liabilities and stockholders’ equity	$	8,936,624	$	8,301,741

(1)Effective January 1, 2008, in connection with the restructuring of BioMarin/Genzyme LLC, our joint venture with BioMarin Pharmaceutical Inc., we licensed certain rights to commercialize Aldurazyme from the joint venture and began consolidating the results of the joint venture at fair value in accordance with FIN 46R.  As of December 31, 2008, intangibles, net, and noncurrent liabilities each include a net $456,475K for the fair values associated with the joint venture’s manufacturing and commercialization rights to Aldurazyme. Excluding these rights, the fair value of the assets and liabilities of the joint venture as of December 31, 2008 was not significant.

Genzyme Corporation (GENZ)

Analyst Schedule

(Unaudited, amounts in thousands, except percentage amounts)

											Q4-08 vs. Q4-07
	Q4-07		Q1-08		Q2-08		Q3-08		Q4-08		% B/(W)		FY 2006		FY 2007		FY 2008
Total revenues:
Genetic Diseases
Cerezyme	$	300,312	$	304,303	$	319,360	$	309,280	$	306,034	2	%	$	1,007,036	$	1,133,153	$	1,238,977
Fabrazyme	114,661		116,475		126,608		125,619		125,558		10	%	359,274		424,284		494,260
Myozyme	62,496		67,324		77,222		76,663		74,967		20	%	59,238		200,728		296,176
Aldurazyme	—		37,015		38,834		38,236		37,579				—		—		151,664
Other Genetic Diseases	7,289		9,772		10,437		11,367		14,039		93	%	410		8,314		45,615
Total Genetic Diseases product and service revenue	484,758		534,889		572,461		561,165		558,177		15	%	1,425,958		1,766,479		2,226,692
R&D Revenue	5		—		—		—		—				1,000		1,059		—
Total Genetic Diseases	484,763		534,889		572,461		561,165		558,177		15	%	1,426,958		1,767,538		2,226,692
Cardiometabolic and Renal
Renagel and Renvela (including Sevelamer)	166,173		168,694		168,567		170,992		169,476		2	%	515,119		602,670		677,729
Hectorol	29,855		29,076		30,852		33,825		34,400		15	%	93,360		115,708		128,153
Subtotal	196,028		197,770		199,419		204,817		203,876		4	%	608,479		718,378		805,882
Thyrogen	30,881		33,785		39,448		38,153		37,062		20	%	93,687		113,587		148,448
Other Cardiometabolic and Renal	92		251		333		573		496		>100	%	—		103		1,653
Total Cardiometabolic and Renal product and service revenue	227,001		231,806		239,200		243,543		241,434		6	%	702,166		832,068		955,983
R&D revenue	102		32		85		56		27		(74	)%	2,142		1,200		200
Total Cardiometabolic and Renal	227,103		231,838		239,285		243,599		241,461		6	%	704,308		833,268		956,183
Biosurgery
Synvisc	62,685		56,142		70,927		67,513		68,512		9	%	233,858		242,319		263,094
Sepra products	29,746		30,604		34,780		33,001		35,278		19	%	85,338		104,318		133,663
Other Biosurgery	21,122		24,313		24,690		21,787		20,908		(1	)%	67,480		74,673		91,698
Total Biosurgery product and service revenue	113,553		111,059		130,397		122,301		124,698		10	%	386,676		421,310		488,455
R&D revenue	666		603		818		661		563		(15	)%	893		5,337		2,645
Total Biosurgery	114,219		111,662		131,215		122,962		125,261		10	%	387,569		426,647		491,100
Hematologic Oncology
Total Hematologic Oncology product and service revenue	21,628		22,691		26,443		26,328		27,437		27	%	49,179		69,927		102,899
R&D revenue	1,216		1,189		1,903		2,292		9,055		>100	%	8,097		7,006		14,439
Total Hematologic Oncology	22,844		23,880		28,346		28,620		36,492		60	%	57,276		76,933		117,338
Other
Genetic/Diagnostics product and service revenue	108,872		114,748		116,863		121,163		124,840		15	%	355,866		410,917		477,614
Transplant product and service revenue	47,424		45,930		47,763		47,784		50,723		7	%	155,966		174,826		192,200
Other product and service revenue	27,981		31,009		29,296		28,598		30,252		8	%	93,716		108,577		119,155
Total Other product and service revenue	184,277		191,687		193,922		197,545		205,815		12	%	605,548		694,320		788,969
R&D revenue	3,552		6,105		5,905		6,393		6,354		79	%	5,354		14,813		24,757
Total Other	187,829		197,792		199,827		203,938		212,169		13	%	610,902		709,133		813,726
Total revenues	$	1,036,758	$	1,100,061	$	1,171,134	$	1,160,284	$	1,173,560	13	%	$	3,187,013	$	3,813,519	$	4,605,039

All amounts herein are presented in accordance with GAAP and are provided for quantitative analysis only and should be read in conjunction with the text of the Earnings Release and our audited financial statements filed with the Securities and Exchange Commission.  Please refer to our Form 10-Q’s and Form 10-K’s for an in-depth discussion and analysis of our results of operations and financial position and for detailed information regarding specific material transactions in a particular period.

GENZYME CORPORATION

RECONCILIATION OF GAAP TO NON-GAAP EARNINGS

For the Three Months Ended December 31, 2008

(Amounts in thousands, except percentage and per share data)

						(1)
						Dilution			(2)
						Due to			Validation/			(3)
						Common Stock			Inventory			License						FAS 123R			GAAP
	NON-GAAP					Equivalents			Write-offs			Fee			Amortization			Expense			As Reported
Income Statement Classification:
Total revenues			$	1,173,560																			$	1,173,560
Cost of products and services sold			$	(270,293	)				$	(12,614	)							$	(7,804	)			$	(290,711	)
Gross margin	77	%	$	903,267					$	(12,614	)							$	(7,804	)	75	%	$	882,849
Selling, general and administrative			$	(317,599	)													$	(23,730	)			$	(341,329	)
Research and development			$	(188,040	)				$	(11,039	)	$	(146,000	)				$	(13,351	)			$	(358,430	)
Amortization of intangibles			$	—											$	(59,884	)						$	(59,884	)
Charge for impaired asset			$	(2,036	)																		$	(2,036	)
Equity in income (loss) of equity method investments			$	13																			$	13
Minority interest			$	625																			$	625
Gains (losses) on investments in equity securities			$	861																			$	861
Other			$	(1,021	)																		$	(1,021	)
Investment income			$	11,245																			$	11,245
Interest expense			$	(822	)																		$	(822	)
Summary:
Income (loss) before income taxes			$	406,493		$	—		$	(23,653	)	$	(146,000	)	$	(59,884	)	$	(44,885	)			$	132,071
(Provision for) benefit from income taxes	29	%	$	(118,006	)	$	—		$	5,724		$	52,401		$	1,116		$	13,344		34	%	$	(45,421	)
Net income (loss)			$	288,487		$	—		$	(17,929	)	$	(93,599	)	$	(58,768	)	$	(31,541	)			$	86,650
Net income (loss) per share:
Basic			$	1.07		$	—		$	(0.07	)	$	(0.35	)	$	(0.22	)	$	(0.12	)			$	0.32
Diluted (1)			$	1.04		$	(0.02	)	$	(0.06	)	$	(0.33	)	$	(0.21	)	$	(0.11	)			$	0.31
Weighted average shares outstanding:
Basic			270,658																				270,658
Diluted (1)			277,928			6,410																	284,338

GENZYME CORPORATION

RECONCILIATION OF GAAP to NON-GAAP CASH GENERATED

For the Three Months Ended December 31, 2008

(Amounts in thousands)

Non-GAAP Net Income	$	288,487
Depreciation, net of tax	24,684
Proceeds from the issuance of common stock	24,150
Non-GAAP Cash Generated	$	337,321

Notes:

The amounts above represent the Non-GAAP operations and financial position of Genzyme Corporation for the three months ended December 31, 2008.  Genzyme believes that certain non-GAAP financial measures, when considered together with the GAAP figures, can enhance the 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 investors with a more complete understanding of the trends underlying our operating results and financial position and are among the primary indicators Genzyme management uses for planning and forecasting purposes and measuring the company’s performance.  Such non-GAAP financial measures should not be considered in isolation or used as a substitute for GAAP.

(1)  GAAP As-Reported diluted earnings per share and diluted weighted average shares outstanding reflect the adoption of EITF 04-8. In accordance with the provisions of EITF 04-8, interest and debt fees related to our 1.25% convertible senior notes of $1,257K, net of tax, have been added back to net income and approximately 6,410K shares have been added to diluted weighted average shares outstanding for purposes of computing GAAP As-Reported diluted earnings per share.

(2)  Represents the write-off of inventory associated with partial production runs $(12,614)K and validation costs associated with our Belgium facility $(11,039)K.

(3)  Represents an up-front expense for the license or purchase of certain intellectual property and technology, of which $(130,000)K relates to our collaboration with Osiris Therapeutics, Inc.; and $(10,000)K and $(6,000)K each relate to transactions with two other third parties.

GENZYME CORPORATION

RECONCILIATION OF GAAP TO NON-GAAP EARNINGS

Year to Date as of December 31, 2008

(Amounts in thousands, except percentage and per share data)

						Dilution
						Due to				Validation/
						Common Stock				Inventory				Strategic Equity				Gain (Loss) on				License								FAS 123R				GAAP
	NON-GAAP					Equivalents				Write-offs				Investment				Investments				Fees				Amortization				Expense				As Reported
Income Statement Classification:
Total revenues			$	4,605,039																																$	4,605,039
Cost of products and services sold			$	(1,108,393	)					$	(12,614		)																	$	(27,555		)			$	(1,148,562		)
Gross margin	76	%	$	3,496,646						$	(12,614		)																	$	(27,555		)	75	%	$	3,456,477
Selling, general and administrative			$	(1,235,445	)																									$	(102,745		)			$	(1,338,190		)
Research and development			$	(749,718	)					$	(11,039		)	$	(69,900		)					$	(421,000		)					$	(56,673		)			$	(1,308,330		)
Amortization of intangibles			$	—																						$	(226,442		)							$	(226,442		)
Charge for impaired assets			$	(2,036	)																															$	(2,036		)
Equity in income (loss) of equity method investments			$	201																																$	201
Minority interest			$	2,217																																$	2,217
Gains (losses) on investments in equity securities			$	1,913														$	(5,253		)															$	(3,340		)
Other			$	(1,861	)																															$	(1,861		)
Investment income			$	51,260																																$	51,260
Interest Expense			$	(4,418	)																															$	(4,418		)
Summary:
Income (loss) before income taxes			$	1,558,759		$	—			$	(23,653		)	$	(69,900		)	$	(5,253		)	$	(421,000		)	$	(226,442		)	$	(186,973		)			$	625,538
(Provision for) benefit from income taxes	29	%	$	(451,038	)	$		—		$		5,724		$		13,428		$		390		$		94,900		$		75,399		$		56,740		33	%	$		(204,457	)
Net income (loss)			$	1,107,721		$	—			$	(17,929		)	$	(56,472		)	$	(4,863		)	$	(326,100		)	$	(151,043		)	$	(130,233		)			$	421,081
Net income (loss) per share:
Basic			$	4.12		$	—			$	(0.07		)	$	(0.21		)	$	0.02			$	(1.21		)	$	(0.56		)	$	(0.50		)			$	1.57
Diluted (1)			$	4.00		$	(0.11		)	$	(0.06		)	$	(0.20		)	$	(0.01		)	$	(1.14		)	$	(0.53		)	$	(0.45		)			$	1.50
Weighted average shares outstanding:
Basic			268,490																																	268,490
Diluted (1)			276,744			8,851																														285,595

GENZYME CORPORATION

RECONCILIATION OF GAAP to NON-GAAP CASH GENERATED

For the Year Ended December 31, 2008

(Amounts in thousands)

	Q1-08		Q2-08		Q3-08		Q4-08		2008
Non-GAAP Net Income	$	260,895	$	268,546	$	289,793	$	288,487	$	1,107,721
Depreciation, net of tax	22,500		23,286		23,881		24,684		94,351
Proceeds from the issuance of common stock	90,243		36,765		167,595		24,150		318,753
Non-GAAP Cash Generated	$	373,638	$	328,597	$	481,269	$	337,321	$	1,520,825

Notes:

The amounts above represent the Non-GAAP operations and financial position of Genzyme Corporation in 2008.  A reconciliation of GAAP to Non-GAAP net income for each quarter is available in the investors section at www.genzyme.com.  Genzyme believes that certain non-GAAP financial measures, when considered together with the GAAP figures, can enhance the 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 investors with a more complete understanding of the trends underlying our operating results and financial position and are among the primary indicators Genzyme management uses for planning and forecasting purposes and measuring the company’s performance.  Such non-GAAP financial measures should not be considered in isolation or used as a substitute for GAAP.

(1)  GAAP As-Reported diluted earnings per share and diluted weighted average shares outstanding reflect the adoption of EITF 04-8. In accordance with the provisions of EITF 04-8, interest and debt fees related to our 1.25% convertible senior notes of $6,915K, net of tax, have been added back to net income and approximately 8,851K shares have been added to diluted weighted average shares outstanding for purposes of computing GAAP As-Reported diluted earnings per share.

GENZYME 2009 GUIDANCE

	2009 Guidance
DESCRIPTION	Ranges
Genetic Diseases	$	2,465	$	2,525
Cardiometabolic and Renal	1,035		1,065
Biosurgery	540		570
Hematologic Oncology	185		210
Other	1,020		1,075
TOTAL REVENUE	$	5,200	$	5,400
*GROSS MARGIN	approx.		75		%
*SG&A	approx.		26		%
*R&D	approx.		16		%
Net Interest / Other	approx.		30
TAX RATE - GAAP	approx.		30		%
*TAX RATE - NON-GAAP	approx.		29		%
GAAP EPS	approx.		$	3.50
AMORTIZATION	approx.		$	0.70
FAS123R EXPENSE	approx.		$	0.50
*NON-GAAP EPS			$	4.70
WTD AVERAGE DILUTED SHARES O/S	280		282
CAPITAL EXPENDITURES	$	600	$	650

This financial guidance, which is provided as part of a press release dated February 11, 2009, is subject to all of the qualifications and limitations described therein.  Actual results may differ from these forward-looking statements due to the numerous factors described in the press release.

*Non-GAAP excludes the impact of amortization, one-time events and FAS123R expense.

SELECT PRODUCT GUIDANCE:
Cerezyme	$	1,250	$	1,275
Fabrazyme	560		570
Myozyme	430		440
Mozobil	40		50
Renagel/Renvela	725		735