________________________

1 DNA Way, South San Francisco, California  94080-4990
(Address of principal executive offices and Zip Code)

(650) 225-1000
(Registrant's telephone number, including area code)

            Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  Yes [x]  No [ ]

            Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).  Yes [x]  No [ ]

            Indicate the number of shares outstanding of each of the issuer's classes of common stock, as of the latest practicable date.

            In this report, "Genentech," "we," "us" and "our" refer to Genentech, Inc. "Common Stock" refers to Genentech's common stock, par value $0.02 per share and "Special Common Stock" refers to Genentech's callable putable common stock, par value $0.02 per share.

            We own or have rights to various copyrights, trademarks and trade names used in our business including the following: Activase® (alteplase, recombinant) tissue-plasminogen activator; Avastin™ (bevacizumab) anti-VEGF antibody; Cathflo® Activase® (alteplase for catheter clearance); Herceptin® (trastuzumab) anti-HER2 antibody; Nutropin® (somatropin (rDNA origin) for injection) growth hormone; Nutropin AQ® and Nutropin AQ Pen™ (somatropin (rDNA origin) for injection) liquid formulation growth hormone; Nutropin Depot® (somatropin (rDNA origin) for injectable suspension) encapsulated sustained-release growth hormone; Protropin® (somatrem for injection) growth hormone; Pulmozyme® (dornase alfa, recombinant) inhalation solution; TNKase™ (tenecteplase) single-bolus thrombolytic agent; and Raptiva™ (efalizumab, formerly Xanelim™) anti-CD11a antibody. Rituxan® (rituximab) anti-CD20 antibody is a registered trademark of IDEC Pharmaceuticals Corporation; Tarceva™ (erlotinib) is a trademark of OSI Pharmaceuticals, Inc.; and Xolair® (omalizumab) anti-IgE antibody is a trademark of Novartis AG. This report also includes other trademarks, service marks and trade names of other companies.

Page 2

Page 3

Page 4

Page 5

            In the opinion of management, the accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. In the opinion of management, all adjustments (consisting only of adjustments of a normal recurring nature) considered necessary for a fair presentation have been included. Operating results for the three month period ended March 31, 2003 are not necessarily indicative of the results that may be expected for the year ending December 31, 2003. The Condensed Consolidated Balance Sheet as of December 31, 2002 has been derived from the audit ed consolidated financial statements as of that date. For further information, refer to the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2002.

            The preparation of financial statements in conformity with generally accepted accounting principles in the United States (or U.S.) requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.

            In June 2002, the Financial Accounting Standards Board (or FASB) issued FAS 146, "Accounting for Costs Associated with Exit or Disposal Activities," which addresses accounting for restructuring, discontinued operation, plant closing, or other exit or disposal activity. FAS 146 requires companies to recognize costs associated with exit or disposal activities when they are incurred rather than at the date of a commitment to an exit or disposal plan. FAS 146 is to be applied prospectively to exit or disposal activities initiated after December 31, 2002. The adoption of FAS 146 on January 1, 2003 did not have a significant impact on our financial position and results of operations.

            In November 2002, the FASB issued Interpretation No. 45 (or FIN 45), "Guarantor's Accounting and Disclosure Requirements for Guarantees, Including Indirect Guarantees of Indebtedness of Others." FIN 45 elaborates on the existing disclosure requirements for most guarantees, including residual value guarantees issued in conjunction with operating lease agreements. It also clarifies that at the time a company issues a guarantee, the company must recognize an initial liability for the fair value of the obligation it assumes under that guarantee and must disclose that information in its interim and annual financial statements. The initial recognition and measurement provisions apply on a prospective basis to guarantees issued or modified after December 31, 2002. The disclosure requirements are effective for financial statements of interim or annual periods ending after December 15, 2002. Our adoption of FIN 45 did not have a material impact on our results of operations and financial position. See Note 2, "Leases and Contingencies," below for a discussion of our exposure related to our agreement with Serono S.A. and our synthetic leases and the related residual value guarantees.

            In January 2003, the FASB issued Interpretation No. 46 (or FIN 46), "Consolidation of Variable Interest Entities." FIN 46 requires a variable interest entity to be consolidated by a company if that company is subject to a majority of the risk of loss from the variable interest entity's activities or entitled to receive a majority of the entity's residual returns or both. A variable interest entity is a corporation, partnership, trust, or any other legal structures used for business purposes that either (a) does not have equity investors with voting rights or (b) has equity investors that do not provide sufficient financial resources for the entity to support its activities. A variable interest entity

Page 6

often holds financial assets, including loans or receivables, real estate or other property. A variable interest entity may be essentially passive or it may engage in research and development or other activities on behalf of another company. The consolidation requirements of FIN 46 apply immediately to variable interest entities created after January 31, 2003. The consolidation requirements apply to older entities in the first fiscal year or interim period beginning after June 15, 2003. Certain of the disclosure requirements apply to all financial statements issued after January 31, 2003, regardless of when the variable interest entity was established. See Note 2, "Leases and Contingencies," below for a discussion of our synthetic leases and the expanded disclosures required by FIN 46.

            In December 2002, the FASB issued Statement No. 148, "Accounting for Stock-Based Compensation - Transition and Disclosure." FAS 148 amends FAS 123 "Accounting for Stock-Based Compensation" to provide alternative methods of transition for a voluntary change to the fair value based method of accounting for stock-based employee compensation. In addition, FAS 148 amends the disclosure requirements of FAS 123 to require more prominent disclosures in both annual and interim financial statements about the method of accounting for stock-based employee compensation and the effect of the method used on reported results. The additional disclosure requirements of FAS 148 are effective for fiscal years ending after December 15, 2002. We have elected to continue to follow the intrinsic value method of accounting as prescribed by Accounting Principles Board Opinion No. 25 (or APB 25), "Accounting for Stock Issued to Employees," t o account for employee stock options. Under APB 25, no compensation expense is recognized unless the exercise price of our employee stock options is less than the market price of the underlying stock on the date of grant. We have not recorded such expenses in the periods presented because we grant options at the fair market value of the underlying stock on the date of grant.

            The following information regarding net income and earnings per share prepared in accordance with FAS 123 has been determined as if we had accounted for our employee stock options and employee stock plan under the fair value method prescribed by FAS 123. The resulting effect on net income and earnings per share pursuant to FAS 123 is not likely to be representative of the effects on net income and earnings per share pursuant to FAS 123 in future periods, due to subsequent periods including additional grants and periods of vesting. The fair value of options was estimated at the date of grant using a Black-Scholes option valuation model with the following weighted-average assumptions for the three months ended March 31, 2003 and 2002, respectively:  risk-free interest rates of 2.8% and 4.4%; dividend yields of 0%; volatility factors of the expected market price of our Common Stock of 36.0% and 43.0%; and a we ighted-average expected life of the option of five years.

            The Black-Scholes option valuation model was developed for use in estimating the fair value of traded options, which have no vesting restrictions and are fully transferable. Option valuation models require the input of highly subjective assumptions including the expected stock price volatility. Because our employee stock options have characteristics significantly different from those of traded options, and because changes in the subjective input assumptions can materially affect the fair value estimate, in management's opinion the existing models do not provide a reliable single measure of the fair value of our employee stock options.

            For purposes of disclosures pursuant to FAS 123 as amended by FAS 148, the estimated fair value of options is amortized to expense over the options' vesting period.

Page 7

            The following table illustrates the effect on reported net income and earnings per share if we had applied the fair value recognition provisions of FAS 123 to stock-based employee compensation (in thousands, except per share amounts):

            We prepare estimates for sales returns and allowances, discounts and rebates based primarily on historical trends and experience and changes in customer financial conditions.

            In the first quarter of 2003, we made certain classification changes in our Condensed Consolidated Statements of Income. A new caption titled "other income, net" was added to the Condensed Consolidated Statements of Income (see below for the composition of this new caption). The "contract and other" caption presented in prior periods was changed to "contract revenues" and the gains from the sale of biotechnology equity securities that were previously included in "contract and other" are now reflected in "other income, net." In addition, write-downs on biotechnology equity securities previously included in "marketing, general and administrative" expenses are now also reflected in the "other income, net" caption.

            The following table summarizes the components of "other income, net," for the first quarters of 2003 and 2002 (in thousands):

            As part of our strategic alliance efforts, we invested in debt and equity securities of certain biotechnology companies with which we have or have had collaborative agreements. "Other income, net" in the Condensed Consolidated Statements of Income includes realized gains and losses from the sale of certain of these biotechnology equity securities and write-downs for other-than-temporary declines in the fair value of certain of these biotechnology debt and equity securities. In addition, "other income, net," includes interest income and interest expense, net of amounts capitalized.

            Certain reclassifications of prior year amounts have been made to our Condensed Consolidated Statements of Income and our Condensed Consolidated Balance Sheets to conform with the current year presentation.

Page 8

            We lease various real properties under operating leases that generally require us to pay taxes, insurance, maintenance and minimum lease payments. Some of our leases have options to renew. Four of our operating leases are commonly referred to as synthetic leases. A synthetic lease represents a form of off-balance sheet financing under which an unrelated third-party funds 100% of the costs of the acquisition and/or construction of the property and leases the asset to a lessee (Genentech), and at least 3% of the third-party funds represent at-risk equity. As the lessee, our synthetic leases are treated as operating leases for accounting purposes and as financing leases for tax purposes. (See also below regarding FIN 46). Under our synthetic lease structures, upon termination or expiration, at our option, we must either purchase the property from the lessor at a predetermined amount that does not constitute a purcha se at less than fair market value, sell the real property to a third-party, or renew the lease arrangement. If the property is sold to a third-party at an amount less than the amount financed by the lessor, we have agreed under residual value guarantees to pay the lessor up to an agreed upon percentage of the amount financed by the lessor.

            Three of our four synthetic leases were entered into with BNP Paribas Leasing Corporation (or BNP), who leases directly to us various buildings that we occupy in South San Francisco, California. Under certain of these leases, we are required to maintain cash collateral of $56.6 million, which we have included in our Condensed Consolidated Balance Sheets as restricted cash.

            The most significant of our synthetic leases relates to our manufacturing facility located in Vacaville, California. In November 2001, we completed a synthetic lease transaction for this facility, which had previously been leased to us under a predecessor synthetic lease. This new synthetic lease is structured differently from our other synthetic leases. As the lessee, we lease the property from an unrelated special purpose trust (owner/lessor) under an operating lease agreement for five years ending November 2006. Third-party financing is provided in the form of a 3% at-risk equity participation from investors and 97% debt commitment. Investors' equity contributions were equal to or greater than 3% of the fair value of the property at the lease's inception and are required to remain so for the term of the lease. A bankruptcy-remote, special purpose corporation (SPC) was formed to fund the debt portion through the issuance of commercial paper notes. The SPC lends the proceeds from the commercial paper to the owner/lessor, who issues promissory notes to the SPC. The SPC loans mature in November 2006. The SPC promissory notes are supported by a credit facility provided by financing institutions and draws are generally available under that credit facility to repay the SPC's commercial paper. The collateral for the SPC loans includes the leased property, and an interest in the residual value guarantee provided by us. As the lessee, at any time during the lease term, we have the option to purchase the property at an amount that does not constitute a purchase at less than fair market value. Our off-balance sheet contingent liability under the residual value guarantees is summarized in the table below.

            Under all the synthetic leases, Genentech, as the lessee, is also required to maintain certain pre-defined financial ratios and is limited to the amount of debt it can assume. In addition, no Genentech officers or employees have any financial interest with regards to these synthetic lease arrangements or with any of the special purpose entities used in these arrangements. In the event of a default, the maximum amount payable under the residual value guarantee would equal 100% of the amount financed by the lessor, and our obligation to purchase the leased properties or pay the related residual value guarantees could be accelerated. We believed at the lease's inception and continue to believe that the occurrence of any event of default that could trigger our purchase obligation is remote.

Page 9

            Future minimum lease payments under operating leases, exclusive of the residual value guarantees, executory costs and sublease income, at December 31, 2002, are as follows (in millions). These minimum lease payments were computed based on interest rates current at that time, which are subject to fluctuations in certain market-based interest rates:

            The following summarizes the approximate assumed carrying values of the leased properties as of December 31, 2002, which represents the initial fair values of the facilities at the inception of the related lease, less assumed depreciation through June 30, 2003, and residual value guarantee amounts for our synthetic leases (in millions):

            We believe that there have been no impairments in the fair value or use of the properties that we lease under synthetic leases wherein we believe that we would be required to pay amounts under any of the residual value guarantees. We will continue to assess the fair values of the underlying properties and the use of the properties for impairment on an annual basis.

            The maximum exposure to loss on our synthetic leases include (i) residual value guarantee payments as shown above, (ii) certain tax indemnifications in the event the third-parties are obligated for certain federal, state or local taxes as a result of their participation in the transaction, and (iii) indemnification for various losses, costs and expenses incurred by the third-party participants as a result of their ownership of the leased property or participation in the transaction, and as a result of the environmental condition of the property. The additional taxes, losses and expenses as described in (ii) and (iii) are contingent upon the existence of certain conditions and, therefore, would not be quantifiable at this time. However, we do not expect these additional taxes, losses and expenses to be material. In the case of Lease 1, we have pledged cash collateral of $56.6 million as a source of payment for Genent ech's obligation for the residual value guarantee payments and other amounts we owe under the lease.

            Under the FASB's new rule, FIN 46, "Consolidation of Variable Interest Entities," it is likely that some or all of the above synthetic leasing structures qualify as variable interest entities that Genentech, as the primary beneficiary, would be required to consolidate. We have determined that the leasing structure used in the Vacaville Lease will likely qualify as a variable interest entity under FIN 46. Accordingly, with respect to our Vacaville Lease, we estimate that we will need to consolidate assets of $359.0 million, net of accumulated depreciation, liabilities of $412.3 million and noncontrolling interests of $12.7 million, and expect to record a charge of $39.6 million, net of tax, as a cumulative effect of an accounting change on July 1, 2003. With regard to BNP Leases 1, 2 and 3, we are currently evaluating these leases and are seeking additional information from the lessor to determine whether or not we w ill need to consolidate the related assets under FIN 46 on July 1, 2003.

            In August 2002, we entered into an agreement with Serono S.A. to market Raptiva internationally outside the United States, Japan, and certain other Asian countries. In February 2003, we amended the agreement with Serono to expand Serono's marketing rights to include certain Asian countries other than Japan. Development and marketing

Page 10

rights in the United States remain with us and our U.S. collaborator, XOMA (US) LLC, and we retain exclusive marketing rights in Japan. Under the agreement, we and Serono may collaborate on co-developing additional indications of Raptiva and will share certain global development costs. In addition, we have a supply agreement with Serono under which we could have a loss exposure up to a maximum of $10.0 million.

            We are a party to various legal proceedings, including patent infringement litigation relating to our antibody products, and licensing and contract disputes, and other matters.

            We and the City of Hope Medical Center are parties to a 1976 agreement relating to work conducted by two City of Hope employees, Arthur Riggs and Keiichi Itakura, and patents that resulted from that work, which are referred to as the "Riggs/Itakura Patents." Since that time, Genentech has entered into license agreements with various companies to make, use and sell the products covered by the Riggs/Itakura Patents. On August 13, 1999, the City of Hope filed a complaint against us in the Superior Court in Los Angeles County, California, alleging that we owe royalties to the City of Hope in connection with these license agreements, as well as product license agreements that involve the grant of licenses under the Riggs/Itakura Patents. The first trial of this suit began on August 28, 2001. On October 24, 2001, the jury hearing the lawsuit announced that it was unable to reach a verdict and on that basis the Court decl ared a mistrial. City of Hope requested a retrial, and the retrial began on March 20, 2002. On June 10, 2002, the jury voted to award the City of Hope approximately $300 million in compensatory damages. On June 24, 2002, the jury voted to award the City of Hope an additional $200 million in punitive damages. Such amounts were accrued as an expense in the second quarter of 2002 and were included in "litigation-related and other long-term liabilities" in the Condensed Consolidated Balance Sheets at March 31, 2003 and December 31, 2002. Genentech filed a notice of appeal of the verdict and damages awards with the California Court of Appeal. The appeal process is ongoing. The amount of cash, if any, to be paid in connection with the City of Hope matter will depend on the outcome of the appeal.

            On June 7, 2000, Chiron Corporation filed a patent infringement suit against us in the U.S. District Court in the Eastern District of California (Sacramento), alleging that the manufacture, use, sale and offer for sale of our Herceptin antibody product infringes Chiron's U.S. Patent No. 6,054,561. This patent was granted on April 25, 2000, and will expire on June 28, 2005, and it relates to certain antibodies that bind to breast cancer cells and/or other cells. Chiron is seeking compensatory damages for the alleged infringement, additional damages (e.g., for willful infringement), and attorneys' fees and costs. On April 22, 2002, the Court issued its decision ("Markman Order") construing certain aspects of the patent claims that are in dispute. On June 25, 2002, the Court issued several decisions regarding summary judgment motions that previously had been filed by Chiron and us. In those decisions, the Court ruled as a matter of law that Herceptin infringes claims 1 to 25 of Chiron's patent, and also ruled as a matter of law in favor of Chiron on some but not all of Genentech's defenses and counterclaims regarding the alleged invalidity and/or unenforceability of the patent. The trial of this suit began on August 6, 2002. Following the first phase of the trial, which related to Genentech's remaining defenses and counterclaims regarding the alleged invalidity of the patent, the jury unanimously found that claims 1 to 25 of Chiron's patent were invalid, and on that basis the Court entered judgment in favor of Genentech. Chiron filed a notice of appeal with the U.S. Court of Appeals for the Federal Circuit, and Genentech filed a notice of cross-appeal. The appeal process is ongoing.

            On August 12, 2002, the U.S. Patent and Trademark Office (or Patent Office) declared an interference between the Chiron patent involved in the above mentioned lawsuit (U.S. Patent No. 6,054,561) and a patent application exclusively licensed by Genentech from a university relating to anti-HER2 antibodies. An interference proceeding is declared to decide who first made a particular invention where two or more parties claim the same invention, whether the parties' claims are patentable, and consequently who is or is not entitled to a patent on the invention. In declaring this interference, the Patent Office has determined that there is a substantial question as to whether the inventors of the Chiron patent were first to invent and are entitled to this patent. If the Patent Office were to decide that the inventors of the university's patent application were first to invent and that their claims are patentable, a new pat ent would be issued to the university and the Chiron patent would be revoked. On October 24, 2002, the Patent Office redeclared the interference to include, in addition to the above-referenced Chiron patent and university patent application, a number of patents and patent applications owned by either Chiron or Genentech, including Chiron's U.S. Patent No. 4,753,894 that is also at issue in the separate patent infringement lawsuit described below. The interference proceeding is ongoing.

Page 11

            On March 13, 2001, Chiron filed another patent infringement lawsuit against us in the U.S. District Court in the Eastern District of California, alleging that the manufacture, use, sale and/or offer for sale of our Herceptin antibody product infringes Chiron's U.S. Patent No. 4,753,894. Chiron is seeking compensatory damages for the alleged infringement, additional damages, and attorneys' fees and costs. Genentech filed a motion to dismiss this second lawsuit, which was denied. On November 1, 2002, the parties filed a proposed stipulation to stay all proceedings in this lawsuit until (1) the interference involving U.S. Patent No. 4,753,894 is resolved or (2) two years from entry of the proposed stipulation, whichever is sooner. On or about November 13, 2002, the Court entered the stipulation, staying the proceedings as requested by the parties. This lawsuit is separate from and in addition to the Chiron suit menti oned above.

            On July 24, 2002, Green Equity, LLC filed a shareholder derivative lawsuit in the San Francisco Superior Court against Genentech as nominal defendant and against several members of our Board of Directors, and by subsequent amendment of the lawsuit, against several current and former Genentech officers and employees (the "individual defendants"). The lawsuit is based upon the claims made by the City of Hope in the contract dispute referred to above. The complaint alleges that the individual defendants breached the fiduciary duty they owe to Genentech by causing us to withhold royalty payments allegedly due to the City of Hope and to conceal third-party licenses that allegedly should have been disclosed to the City of Hope. The plaintiff seeks unspecified damages, costs, and attorneys' fees. The case was removed to federal court and is now pending in the U.S. District Court in the Northern District of California (San Francisco). Defendants filed motions to dismiss the lawsuit, and on March 6, 2003, the Court issued an order granting in part and denying in part the motions to dismiss. The Court dismissed the Complaint against Genentech and all the individual defendants, except for Jonathan K.C. Knowles. The Court dismissed the Complaint against Knowles with leave to amend. On April 7, 2003, Green Equity, LLC and an additional plaintiff, Warren Jones, filed another amended Complaint against Genentech as nominal defendant and against Dr. Knowles and several other members of our Board of Directors.

            We and Tanox Biosystems, Inc. (or Tanox) are parties to a July 1996 Settlement and Cross-Licensing Agreement relating to the development and manufacture of certain antibody products directed towards immunoglobin E, including Xolair and Hu-901. On February 20, 2002, Tanox filed an amended demand in an ongoing arbitration proceeding between Genentech and Tanox that is being conducted by the American Arbitration Association in San Francisco. In its amended demand, Tanox has claimed breach of the July 1996 Agreement, conversion, tortious interference, unjust enrichment, and unfair competition by Genentech, and requests injunctive relief as well as monetary damages "many times in excess of $100,000,000." On March 14, 2002, Genentech denied all of Tanox's claims, and counterclaimed for breach of contract, theft of trade secrets, misappropriation, breach of confidence, interference with contract, and interference with econ omic expectancies by Tanox. Genentech requested injunctive relief and monetary damages. On October 16, 2002, Tanox announced that in a dispute between it and Novartis, an arbitration panel ruled that Tanox is not entitled to develop independently the Hu-901 antibody product. The Novartis/Tanox panel also ruled that Tanox is entitled to receive certain know-how from Novartis. Tanox contends in its dispute against Genentech that it is entitled to similar information from Genentech. The effect of the October 16 ruling from the Novartis/Tanox arbitration, if any, on Tanox's claims against Genentech cannot be determined since it has not yet been resolved by the arbitrators in the Tanox/Genentech proceedings. As a general matter, the claims are divided into two categories: (1) compensation for lost rights under agreements with Genentech and Novartis, and (2) additional royalties on future sales. The arbitration began on January 13, 2003 and is ongoing. Tanox closed its case on January 30, 2003 and Genentec h closed its case on March 30, 2003. A decision in the arbitration is expected on or before June 13, 2003. The outcome of this matter cannot be determined at this time.

            On April 11, 2003, MedImmune, Inc. filed a lawsuit against Genentech, City of Hope National Medical Center, and Celltech R & D Ltd. in the U.S. District Court for the Central District of California (Los Angeles). The lawsuit relates to U.S. Patent No. 6,331,415 ("the '415 patent") that is co-owned by Genentech and City of Hope and under which MedImmune and other companies have been licensed and are paying royalties to Genentech. The lawsuit includes claims for violation of antitrust, patent, and unfair competition laws. MedImmune is seeking to have the '415 patent declared invalid and/or unenforceable, a determination that MedImmune does not owe royalties under the '415 patent on sales of its Synagis® antibody product, an injunction to prevent Genentech from enforcing the '415 patent, an award of actual and exemplary damages, and other relief. Genentech intends to vigorously defend itself against all of the allegations and claims in this lawsuit. An estimate of any potential loss or range of loss cannot be made at this time.

Page 12

           In the first quarter of 2003, we recorded $13.3 million for accrued interest and costs related to the surety bond we obtained in the third quarter of 2002 for the City of Hope trial judgment. In 2002, we recognized $543.9 million of litigation-related special charges. These special charges were comprised of the City of Hope litigation judgment in the second quarter of 2002, accrued interest and costs related to obtaining a surety bond, and certain other litigation-related matters. In conjunction with the City of Hope judgment, in the third quarter of 2002 we posted a $600.0 million surety bond and as part of this arrangement, we were required to pledge $630.0 million in cash and investments to secure the bond. The $630.0 million cash and investments were classified as restricted cash on our Condensed Consolidated Balance Sheets at March 31, 2003 and December 31, 2002. In addition, we accrued $2.4 million of royalty expe nses related to the City of Hope judgment in the first quarter of 2003, which was reflected in marketing, general and administrative expenses. We expect that we will continue to incur interest charges on the judgment and service fees on the surety bond each quarter through the process of appealing the City of Hope trial results. These special charges represent our best estimate of the costs for the current resolution of these matters and are included in litigation-related and other long-term liabilities in the Condensed Consolidated Balance Sheets at March 31, 2003 and December 31, 2002. We developed this estimate in consultation with outside counsel handling our defense in these matters and it is based upon the facts and circumstances of these matters known to us at that time. The amount of our liability for certain of these matters could exceed or be less than the amount of our current estimate, depending on the outcome of these matters. The amount of cash, if any, paid in connection with the City of Hope matter will depend on the outcome of the appeal.

            On June 30, 1999, we redeemed all of our outstanding Special Common Stock held by stockholders other than Roche Holdings, Inc. (or Roche) with funds deposited by Roche for that purpose. This event, referred to as the "Redemption," caused Roche to own 100% of our common stock on that date. The Redemption was reflected as a purchase of a business which under U.S. generally accepted accounting principles, required push-down accounting to reflect in our financial statements the amount paid for our stock in excess of our net book value plus Roche's transaction costs at June 30, 1999. See Note 4, "Goodwill and Other Intangible Assets," for the amortization of our other intangible assets.

            We expect from time to time to issue additional shares of common stock in connection with our stock option and stock purchase plans, and we may issue additional shares for other purposes. Our affiliation agreement with Roche provides, among other things, that we will establish a stock repurchase program designed to maintain Roche's percentage ownership interest in our common stock. The affiliation agreement provides that we will repurchase a sufficient number of shares pursuant to this program such that, with respect to any issuance of common stock by Genentech in the future, the percentage of Genentech common stock owned by Roche immediately after such issuance will be no lower than Roche's lowest percentage ownership of Genentech common stock at any time after the offering of common stock occurring in July 1999 and prior to the time of such issuance, except that Genentech may issue shares up to an amount that would cause Roche's lowest percentage ownership to be no more than 2% below the "Minimum Percentage." The Minimum Percentage equals the lowest number of shares of Genentech common stock owned by Roche since the July 1999 offering (to be adjusted in the future for dispositions of shares of Genentech common stock by Roche as well as for stock splits or stock combinations) divided by 509,194,352 (to be adjusted in the future for stock splits or stock combinations), which is the number of shares of Genentech common stock outstanding at the time of the July 1999 offering, as adjusted for the two-for-one splits of Genentech common stock in November 1999 and October 2000. As long as Roche's percentage ownership is greater than 50%, prior to issuing any shares, the affiliation agreement provides that we will repurchase a sufficient number of shares of our common stock such that, immediately after our issuance of shares, Roche's percentage ownership will be greater than 50%. The affiliation agreement also provides that , upon Roche's request, we will repurchase shares of our common stock to increase Roche's ownership to the Minimum Percentage. In addition, Roche will have a continuing option to buy stock from us at prevailing market prices to maintain its percentage ownership interest. On March 31, 2003, Roche's percentage ownership of our common stock was 60.1%.

Page 13

            Goodwill represents the difference between the purchase price and the fair value of the net assets when accounted for by the purchase method of accounting arising from the Redemption (see above Note 3, "Relationship With Roche"). The carrying amount of goodwill at March 31, 2003 and December 31, 2002 was $1,334.2 million. We performed an impairment test of goodwill upon adoption of FAS 142 on January 1, 2002, and an impairment test on September 30, 2002, and found no impairment. We will continue to monitor the carrying value of our goodwill through impairment tests performed at least annually.

            The components of our acquisition-related intangible assets arising from the Redemption and push-down accounting (see above Note 3, "Relationship With Roche"), patents and other intangible assets at March 31, 2003 and December 31, 2002, are as follows (in millions):

            Amortization expense of our other intangible assets was $43.0 million in the first quarter of 2003 and $42.4 million in the first quarter of 2002.

            The expected future annual amortization expense of our other intangible assets is as follows (in millions):

            We record gains and losses on derivatives related to our equity hedging instruments in "other income, net" in the Condensed Consolidated Statements of Income. We had no such gains or losses in the first quarters of 2003 or 2002.

            At March 31, 2003, net losses on derivative instruments expected to be reclassified from accumulated other comprehensive income to earnings during the next twelve months are $3.3 million due to the recognition of premiums related to maturing foreign currency exchange options.

Page 14

            The following table summarizes activity in other comprehensive income (or OCI) related to derivatives, net of taxes, held during the first quarters of 2003 and 2002 (in thousands):

            Comprehensive income is comprised of net income and OCI. OCI includes certain changes in stockholders' equity that are excluded from net income. OCI includes changes in fair value of derivatives designated as and effective as hedges and unrealized gains and losses on our available-for-sale securities. The following table summarizes the components of total comprehensive income, net of taxes, during the first quarters of 2003 and 2002 (in thousands):

            The components of accumulated other comprehensive income, net of taxes, are as follows (in thousands):

            The following is a reconciliation of the denominator used in basic and diluted earnings per share (EPS) computations for the quarters ended March 31, 2003 and 2002 (in thousands):

            Options to purchase 24,110,816 shares of common stock between $35.87 and $95.66 per share were outstanding in the first quarter of 2003, and options to purchase 9,542,574 shares of common stock between $50.55

Page 15

and $95.66 per share were outstanding in the first quarter of 2002. These options were excluded from the computation of diluted EPS because such options were anti-dilutive in the respective periods presented.

            In anticipation of the launch of Xolair, we produced in prior years approximately $76.6 million of inventory, of which $45.5 million has been paid for by our collaborator, Novartis Pharmaceuticals Corporation, or are covered by inventory reserves. In anticipation of the launch of Raptiva, we produced approximately $11.5 million of inventory, of which $6.9 million has been covered by inventory reserves. The Xolair and Raptiva inventories are included in work in process. Due to the launch delays of Xolair and Raptiva, we continually assess the realizability of these inventories based on expected U.S. Food and Drug Administration approval dates, forecasted sales, and product expiration. Inventories at March 31, 2003 and December 31, 2002 are summarized below (in thousands):

            Under the stock repurchase program approved by our Board of Directors on October 31, 2001, as extended on August 15, 2002, we are authorized to repurchase up to $1 billion of our common stock through the period ending June 30, 2003. Purchases may be made in the open market or in privately negotiated transactions from time to time at management's discretion. We may also engage in transactions in other Genentech securities in conjunction with the repurchase program, including derivative securities. Due to the extension of the stock repurchase program, a new 10b5-1 trading plan was entered into on November 13, 2002, to repurchase shares in the open market during those periods each quarter when trading in our stock is restricted under our insider trading policy. This plan covers 2.5 million shares. Under the stock repurchase program, we repurchased approximately 3.2 million shares of our common stock in the first quar ter of 2003 at a cost of approximately $113.2 million. Of those shares repurchased, approximately 1.2 million were repurchased under our current 10b5-1 insider trading plan. In the first quarter of 2002, we repurchased 3.7 million shares of our common stock at a cost of approximately $179.9 million. Of those shares repurchased, approximately 0.3 million were repurchased under our prior 10b5-1 insider trading plan. Under the stock repurchase program to date, we repurchased approximately 21.5 million shares of our common stock at a cost of approximately $811.6 million during the period from November 1, 2001 through March 31, 2003.

            The par value method of accounting is used for common stock repurchases. The excess of the cost of shares acquired over the par value is allocated to additional paid-in capital with the amounts in excess of the estimated original sales price charged to accumulated deficit.

            The tax provision of $56.0 million in the first quarter of 2003 increased over the tax provision of $33.6 million in the first quarter of 2002 primarily due to increased pretax income and decreased tax credits, partially offset by a $17.0 million favorable change in estimate of prior years items.

            The effective tax rate was 27% in the first quarter of 2003 compared to 26% in the first quarter of 2002. The increase reflects a decrease in tax credits, partially offset by a favorable change in estimate of prior years items.

            Under our stock repurchase program approved by our Board of Directors on October 31, 2001 and extended on August 15, 2002, we have repurchased approximately 1.0 million shares of our common stock at a cost of

Page 16

approximately $34.6 million during the period from April 1, 2003 through April 25, 2003. Of these shares, 0.3 million shares were repurchased at a cost of approximately $12.0 million under our current 10b5-1 insider trading plan. For more information on our stock repurchase program, see the "Capital Stock" note above.

            On April 11, 2003, MedImmune, Inc. filed a lawsuit against Genentech, City of Hope National Medical Center, and Celltech R & D Ltd. in the U.S. District Court for the Central District of California (Los Angeles). The lawsuit relates to U.S. Patent No. 6,331,415 ("the '415 patent") that is co-owned by Genentech and City of Hope and under which MedImmune and other companies have been licensed and are paying royalties to Genentech. The lawsuit includes claims for violation of antitrust, patent, and unfair competition laws. MedImmune is seeking to have the '415 patent declared invalid and/or unenforceable, a determination that MedImmune does not owe royalties under the '415 patent on sales of its Synagis® antibody product, an injunction to prevent Genentech from enforcing the '415 patent, an award of actual and exemplary damages, and other relief. Genentech intends to vigorously defend itself against all of the allegations and claims in this lawsuit. An estimate of any potential loss or range of loss cannot be made at this time.

Page 17

            We have reviewed the accompanying condensed consolidated balance sheet of Genentech, Inc. as of March 31, 2003, and the related condensed consolidated statements of income and cash flows for each of the three-month periods ended March 31, 2003 and 2002. These financial statements are the responsibility of Genentech's management.

            We conducted our reviews in accordance with standards established by the American Institute of Certified Public Accountants. A review of interim financial information consists principally of applying analytical procedures to financial data, and making inquiries of persons responsible for financial and accounting matters. It is substantially less in scope than an audit conducted in accordance with auditing standards generally accepted in the United States, which will be performed for the full year with the objective of expressing an opinion regarding the financial statements taken as a whole. Accordingly, we do not express such an opinion.

            Based on our reviews, we are not aware of any material modifications that should be made to the accompanying condensed consolidated financial statements referred to above for them to be in conformity with accounting principles generally accepted in the United States.

            We have previously audited, in accordance with auditing standards generally accepted in the United States, the consolidated balance sheet of Genentech, Inc. as of December 31, 2002, and the related consolidated statements of operations, stockholders' equity, and cash flows for the year then ended (not presented herein) and in our report dated January 14, 2003 (except for the note titled Subsequent Event, as to which the date is February 12, 2003), we expressed an unqualified opinion on those consolidated financial statements. In our opinion, the information set forth in the accompanying condensed consolidated balance sheet as of December 31, 2002, is fairly stated, in all material respects, in relation to the consolidated balance sheet from which it has been derived.

Palo Alto, California
April 8, 2003, except
for Note 11, as to which
the date is April 25, 2003

Page 18

            Genentech is a leading biotechnology company using human genetic information to discover, develop, manufacture and commercialize biotherapeutics for significant unmet medical needs. We manufacture and commercialize 10 biotechnology products listed below and license several additional products to other companies.

• Herceptin (trastuzumab) antibody for the treatment of certain patients with metastatic breast cancer whose tumors overexpress the Human Epidermal growth factor Receptor type 2 (or HER2) protein;

• Rituxan (rituximab) antibody which we market together with IDEC Pharmaceuticals Corporation (or IDEC) for the treatment of patients with relapsed or refractory low-grade or follicular, CD20-positive B-cell non-Hodgkin's lymphoma;

• TNKase (tenecteplase) single-bolus thrombolytic agent for the treatment of acute myocardial infarction (heart attack);

• Activase (alteplase, recombinant) tissue plasminogen activator (or t-PA) for the treatment of acute myocardial infarction, acute ischemic stroke (brain attack) within three hours of the onset of symptoms and acute massive pulmonary embolism (blood clots in the lungs);

• Cathflo Activase (alteplase, recombinant) tissue plasminogen activator approved for the restoration of function to central venous access devices that have become occluded due to a blood clot;

• Nutropin Depot [somatropin (rDNA origin) for injectable suspension] long-acting growth hormone for the treatment of growth failure associated with pediatric growth hormone deficiency;

• Nutropin AQ [somatropin (rDNA origin) for injection] liquid formulation growth hormone for the same indications as Nutropin;

• Nutropin [somatropin (rDNA origin) for injection] human growth hormone for the treatment of growth hormone deficiency in children and adults, growth failure associated with chronic renal insufficiency prior to kidney transplantation and short stature associated with Turner syndrome;

• Protropin (somatrem for injection) growth hormone for the treatment of inadequate endogenous growth hormone secretion, or growth hormone deficiency, in children (manufacture of Protropin has been discontinued but sales will continue for up to one year until inventory is depleted); and

• Pulmozyme (dornase alfa, recombinant) inhalation solution for the treatment of cystic fibrosis.

            We receive royalties on sales of rituximab, Pulmozyme and Herceptin outside of the United States and on sales of human growth hormone, Rituxan, Pulmozyme, Activase and TNKase in Canada from F. Hoffmann-La Roche (or Hoffmann-La Roche). We receive royalties from third parties on sales of growth hormone products within the United States and outside of the United States, on sales of t-PA outside of the United States and Canada, and on sales of tenecteplase outside of the United States, Canada and Japan. We also receive worldwide royalties on additional licensed products that are marketed by other companies.

Page 19

            On June 30, 1999, we redeemed all of our outstanding Special Common Stock held by stockholders other than Roche Holdings, Inc. (or Roche) at a price of $20.63 per share in cash with funds deposited by Roche for that purpose. We refer to this event as the "Redemption." As a result, on that date, Roche's percentage ownership of our outstanding Common Stock increased from 65% to 100%. Consequently, under accounting principles generally accepted in the United States, we were required to use push-down accounting to reflect in our financial statements the amounts paid for our stock in excess of our net book value. Push-down accounting required us to record $1,685.7 million of goodwill and $1,499.0 million of other intangible assets onto our balance sheet on June 30, 1999. See also below in the "Recurring Charges Related to Redemption" section of Results of Operations and Note 3, "Relationship With Roche -- Redemption of Our Special Common Stock," in the Notes to Condensed Consolidated Financial Statements.

            We expect from time to time to issue additional shares of common stock in connection with our stock option and stock purchase plans, and we may issue additional shares for other purposes. Our affiliation agreement with Roche provides, among other things, that we establish a stock repurchase program designed to maintain Roche's percentage ownership interest in our common stock. The affiliation agreement provides that we will repurchase a sufficient number of shares pursuant to this program such that, with respect to any issuance of common stock by Genentech in the future, the percentage of Genentech common stock owned by Roche immediately after such issuance will be no lower than Roche's lowest percentage ownership of Genentech common stock at any time after the offering of common stock occurring in July 1999 and prior to the time of such issuance, except that Genentech may issue shares up to an amount that would caus e Roche's lowest percentage ownership to be no more than 2% below the "Minimum Percentage." The Minimum Percentage equals the lowest number of shares of Genentech common stock owned by Roche since the July 1999 offering (to be adjusted in the future for dispositions of shares of Genentech common stock by Roche as well as for stock splits or stock combinations) divided by 509,194,352 (to be adjusted in the future for stock splits or stock combinations), which is the number of shares of Genentech common stock outstanding at the time of the July 1999 offering, as adjusted for the two-for-one splits of Genentech common stock in November 1999 and October 2000. As long as Roche's percentage ownership is greater than 50%, prior to issuing any shares, the affiliation agreement provides that we will repurchase a sufficient number of shares of our common stock such that, immediately after our issuance of shares, Roche's percentage ownership will be greater than 50%. The affiliation agreement also provides that, upo n Roche's request, we will repurchase shares of our common stock to increase Roche's ownership to the Minimum Percentage. In addition, Roche will have a continuing option to buy stock from us at prevailing market prices to maintain its percentage ownership interest. On March 31, 2003, Roche's percentage ownership of our common stock was 60.1%.

            In the first quarter of 2003, we made certain classification changes in our Condensed Consolidated Statements of Income. A new caption titled "other income, net" was added to the Condensed Consolidated Statements of Income (see below in "Results of Operations -- Other Income, Net" for the composition of this new caption). The "contract and other" caption presented in prior periods was changed to "contract revenues" and the gains from the sale of biotechnology equity securities that were previously included in "contract and other" are now reflected in "other income, net." In addition, write-downs on biotechnology equity securities previously included in "marketing, general and administrative" expenses are now also reflected in the "other income, net," caption.

            Certain reclassifications of prior year amounts have been made to our Condensed Consolidated Statements of Income and our Condensed Consolidated Balance Sheets to conform with the current year presentation.

Page 20

             Our quarterly reports on Form 10-Q, annual reports on Form 10-K and our other filings with the Securities and Exchange Commission, and any amendments to such filings, can be found on our website at http://www.gene.com or can be obtained by contacting our Investor Relations Department at (650) 225-1599 or by sending an e-mail message to [email protected].

            The preparation of our financial statements in conformity with accounting principles generally accepted in the United States requires management to make judgments, assumptions and estimates that affect the amounts reported in our financial statements and accompanying notes. Actual results could differ materially from those estimates. The following are critical accounting policies important to our financial condition and results of operations presented in the financial statements and require management to make judgments, assumptions and estimates that are inherently uncertain:

            We lease various real properties under operating leases that generally require us to pay taxes, insurance, maintenance and minimum lease payments. Four of our operating leases are commonly referred to as "synthetic leases." A synthetic lease is a form of off-balance sheet financing under which an unrelated third-party funds 100% of the costs for the acquisition and/or construction of the property and leases the asset to a lessee (Genentech), and at least 3% of the third-party funds represent at-risk equity. As the lessee, our synthetic leases are treated as operating leases for accounting purposes and financing leases for tax purposes. We periodically review the fair values of the properties we lease in order to determine potential accounting ramifications. Adverse changes in the fair value of the properties we lease and changes in the equity participation of third-parties could affect the classification of these leases from operating to financing for accounting purposes. In addition, our adoption of the Financial Accounting Standards Board's Interpretation No. 46, "Consolidation of Variable Interest Entities," and the consolidation of some or all of our synthetic leases effective July 1, 2003, may have a material impact on our financial condition and results of operations. See the "Recent Accounting Pronouncements " section below for a more complete discussion of our synthetic leases.

            We are currently involved in certain legal proceedings as discussed in Note 2, "Leases and Contingencies" in the Notes to Condensed Consolidated Financial Statements of Part I, Item 1 of this Form 10-Q. As of March 31, 2003, we have accrued our estimate of the costs for the current resolution of these matters. We developed these estimates in consultation with outside counsel handling our defense in these matters and it is based upon the facts and circumstances of these matters known to us at that time. The amount of our liability for certain of these matters could exceed or be less than the amount of our current estimates, depending on the outcome of these matters.

• We recognize revenue from product sales when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed and determinable, and collectibility is reasonably assured. Allowances are established for estimated uncollectible amounts, product returns and discounts.

• We receive royalties from licensees, which are based on third-party sales of licensed products or technologies. Royalties are recorded as earned in accordance with the contract terms when third-party results can be reliably measured and collectibility is reasonably assured. Royalty estimates are made in advance of amounts collected using historical and forecasted trends.

• Contract revenue for research and development (or R&D) is recorded as earned based on the performance requirements of the contract. Non-refundable license fees for which no further performance obligations

Page 21

            Research and development (or R&D) expenses include related salaries and benefits, clinical trial and related clinical manufacturing costs, contract and other outside service fees, and facilities and overhead costs. R&D expenses consist of independent R&D costs and costs associated with collaborative R&D and in-licensing arrangements. In addition, we fund R&D at other companies and research institutions under agreements, which we can generally terminate at will. R&D expenses also include activities such as product registries and investigator sponsored trials. R&D costs, including some upfront fees and milestones paid to collaborators, are expensed as incurred. The timing of upfront fees and milestone payments in the future may cause variability in our future R&D expenses.

            Income tax expense is based on pretax financial accounting income under the liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Significant estimates are required in determining our provisions for income taxes. Various internal and external factors may have favorable or unfavorable effects on our future effective tax rate. These factors include, but are not limited to, changes in tax laws, regulations and/or rates, changing interpretations of existing tax laws or regulations, future levels of R&D spending, future levels of capital expenditures, and changes in overall levels of pretax earnings. We believe that our reserves for these uncertainties are adequate.

            We prepare estimates for sales returns and allowances, discounts and rebates based primarily on historical trends and experience and changes in customer financial conditions. If actual future results vary, we may need to adjust our estimates, which could have an impact on earnings in the period of the adjustment.

            Our inventories are stated at the lower of cost or market. Cost is determined using a weighted-average approach, which approximates the first-in first-out method. If inventory costs exceed expected market value due to obsolescence or unmarketability, reserves are recorded for the difference between the cost and the market value. These reserves are determined based on significant estimates.

            Inventories consist of currently marketed products and product candidates awaiting regulatory approval, which are capitalized based on management's judgment of probable near term commercialization. We would be

Page 22

required to expense previously capitalized costs related to pre-approval inventory upon a change in such judgment, due to, among other potential factors, a denial or delay of approval by the necessary regulatory bodies. At March 31, 2003, inventories related to Xolair and Raptiva products, which have not yet received regulatory approval, were $35.7 million, net of related reserves and amounts paid by our collaborator.

            Marketable equity securities and other debt securities are carried at fair value with unrealized gains and losses on securities classified as "available-for-sale" included in accumulated other comprehensive income in stockholders' equity. If the fair value of a security has declined below its carrying value for each trading day for six consecutive months or if the decline is due to a significant adverse event, the impairment is considered to be other-than-temporary. An other-than-temporary decline in fair value of a debt or equity security of a biotechnology company is written down to its estimated fair value with a charge to "other income, net." Other-than-temporary declines in fair value of all other short-term or long-term marketable securities are charged against interest income, included in "other income, net." Some of the factors we consider in determining whether a significant adverse event has occurred with an issuer include, among other things, unfavorable clinical trial results and the prospect for new products, a denial of a product approval by a regulatory body, the termination of a major collaborative partnership and the liquidity position and financing activities of the issuer. The determination of whether a decline in fair value is other-than-temporary requires significant judgment, and can have a material impact on our financial results.

            Nonmarketable equity securities are carried at cost. We periodically monitor the fair value of such securities by reviewing the liquidity position and financing activities of the respective issuers to determine if impairment write-downs are necessary. In the event that impairment write-downs are recorded and subsequently recovered upon the sale of the related security, our financial results will be favorably impacted. We record impairments in "other income, net."

RESULTS OF OPERATIONS
(dollars in millions, except per share amounts)

            This discussion of our Results of Operations contains forward-looking statements regarding the costs related to the completion of in-process projects. Actual results could differ materially. For a discussion of the risks and uncertainties associated with the costs related to the completion of in-process projects see "The Successful Development of Biotherapeutics is Highly Uncertain," "We May Be Unable to Obtain or Maintain Regulatory Approvals for Our Products," "Difficulties or Delays in Product Manufacturing Could Harm Our Business," "Protecting Our Proprietary Rights Is Difficult and Costly" and "We May Be Unable to Retain Skilled Personnel and Maintain Key Relationships" sections of "Forward-Looking Information and Cautionary Factors That May Affect Future Results" below.

            Total operating revenues increased 32% in the first quarter of 2003 from the comparable period in 2002. The increase was due to higher product sales, royalty income and contract revenues. These increases are further discussed below.

Page 23

            Total net product sales increased 26% in the first quarter of 2003 from the comparable period in 2002 due to higher sales of all products. Increased sales volume accounted for a 20% increase, or $96.1 million, in the first quarter of 2003, and was primarily attributable to Rituxan, Pulmozyme, growth hormone and Herceptin products. Higher sales prices accounted for the remainder of the increase in the first quarter of 2003 and were primarily attributable to price increases with respect to our Rituxan, growth hormone, Pulmozyme and Herceptin products.

            Net sales of Rituxan increased 38% in the first quarter of 2003 from the comparable period in 2002. This increase was primarily due to increased use of the product for the treatment of B-cell non-Hodgkin's lymphoma in indolent and aggressive non-Hodgkin's lymphoma (NHL), as well as chronic lymphocytic leukemia (CLL), used in both monotherapy and combination therapy settings. The current approved label indication is for relapsed, indolent or low grade NHL. The increase was also due to, a lesser extent, a price increase. Net sales of Rituxan decreased 2% from the fourth quarter of 2002. While wholesaler inventories of Rituxan were within our typical ranges at the end of both quarters, they were at the higher end of the typical range at the end of December 2002 and at the lower end of the typical range by the end of March 2003. Also, there were fewer billing days in the first quarter of 2003 than in the previous quart er. During the first quarter of 2003, the National Comprehensive Cancer Network (or NCCN) issued guidelines that included the use of Rituxan in the relapsed aggressive NHL setting.

            Net sales of Herceptin increased 8% in the first quarter of 2003 from the comparable period in 2002. The increase was due to penetration in first-line use in the metastatic breast cancer market and a longer average treatment duration. The increase was also due to, a lesser extent, a price increase. The increase was partly offset by a $9.5 million decrease in ex-U.S. sales as there were no Herceptin sales to Hoffmann-La Roche this quarter. Net Herceptin sales decreased 12% from the prior quarter primarily due to no Herceptin sales to Hoffmann-La Roche. In late September 2002, Hoffmann-La Roche received approval from the European Committee for Proprietary Medicinal Products to manufacture Herceptin at its Penzberg, Germany facility. The Penzberg facility will become the primary site for the manufacture of Herceptin to supply ex-U.S. territories. We expect our sales of Herceptin to Hoffmann-La Roche to decline star ting in 2003. However, we will continue to receive royalties from their ex-U.S. sales of Herceptin.

            Net sales of our four growth hormone products, Nutropin Depot, Nutropin AQ, Nutropin, and Protropin, increased 13% in the first quarter 2003 from the comparable period in 2002. The increase was attributable to a price increase and continued strong demand for the products. The continued strong demand reflects our focus on new patient starts using our Nutropin AQ Pen, continued growth in the adult patient market, higher dosing during puberty and an incremental increase in the length of therapy. In late April 2002, the U.S. Food and Drug Administration (or FDA) approved Nutropin AQ Pen, a new delivery system for Nutropin AQ. The Nutropin AQ Pen was launched on July 10, 2002.

Page 24

            Combined net sales of our three thrombolytic products, Activase, TNKase and Cathflo Activase, increased 11% in the first quarter of 2003 from the comparable period in 2002. The increase is primarily due to an increase in sales of Cathflo Activase for catheter clearance. Cathflo Activase received FDA approval in early September 2001 and was launched in late September 2001. Additionally, modest increases in Activase usage for acute ischemic stroke are being observed. The overall size of the thrombolytic market for acute myocardial infarction continues to decline as a result of the increasing use of mechanical reperfusion, early intervention with other therapies in the treatment of acute myocardial infarction, and preventative therapies.

            Net sales of Pulmozyme increased 25% in the first quarter of 2003 from the comparable period in 2002. The increase primarily reflects an increased focus on aggressive treatment of cystic fibrosis early in the course of the disease and, to a lesser extent, a price increase.

            Royalty income increased 39% in the first quarter of 2003 from the comparable period in 2002. The increase was due to higher third-party sales by various licensees, primarily Hoffmann-La Roche on higher sales of our Herceptin and Rituxan products, including gains on foreign currency exchange rates related to such sales.

            Contract revenues were higher in the first quarter of 2003 from the comparable period in 2002. The increase was primarily due to a milestone payment from a third-party collaborator, higher revenues from collaborators and payments from out-licensing a patent to several licensees.

            Cost of sales (or COS) increased 12% in the first quarter of 2003 from the comparable period of 2002. Cost of sales as a percent of product sales decreased to 19% in the first quarter of 2003 from 21% in the first quarter of 2002. The decrease in costs as a percent of sales was primarily due to lower production costs for products sold in the first quarter of 2003 and higher royalty costs in the first quarter of 2002 due to a $5.0 million payment for retroactive royalties.

            In late September 2002, Hoffmann-La Roche received approval from the European Committee for Proprietary Medicinal Products to manufacture Herceptin at its Penzberg, Germany facility. The Penzberg facility

Page 25

will become the primary site for the manufacture of Herceptin to supply ex-U.S. territories. We expect our sales of Herceptin to Hoffmann-La Roche to decline starting in 2003. Accordingly, if our ex- U.S. Herceptin sales decline as expected, our cost as a percent of sales is also expected to decline due to lower gross margins generated by the ex-U.S. Herceptin sales.

            Research and development (or R&D) expenses increased 7% in the first quarter of 2003 from the comparable period in 2002. This increase was largely due to higher development manufacturing expenses, higher clinical development expenses related to products that are primarily in late stage development, including Raptiva, product experience studies and higher research expenses due to an increase in headcount and related expenses. These increases were offset in part by lower in-licensing expenses in the first quarter of 2003.

            The major components of R&D expenses for the quarters ended March 31, 2003 and 2002 were as follows (in millions):