FDA Advisory Panel Recommends Tarceva(R) Approval for Pancreatic Cancer; Committee Supports New Indication for EGFR Inhibitor Tarceva

OSI Pharmaceuticals, Inc. (NASDAQ: OSIP) and Genentech,Inc. (NYSE: DNA) announced today that the Oncologic Drug AdvisoryCommittee (ODAC) appointed by the U.S. Food and Drug Administration(FDA) voted 10 to 3 in favor of recommending approval of Tarceva(R)(erlotinib) in combination with gemcitabine for the treatment ofadvanced pancreatic cancer in patients who have not received previouschemotherapy. Tarceva is the first drug in a Phase III trial to haveshown a significant improvement in overall survival when added togemcitabine chemotherapy in first-line pancreatic cancer. Tarceva isan oral tablet currently approved for use in non-small cell lungcancer (NSCLC) for patients whose disease has progressed after one ormore courses of chemotherapy. The FDA will now review the ODACrecommendation and a decision on Tarceva approval is anticipated byNovember 2, 2005.

"We are pleased with the recommendation of the advisory committeeand we look forward to the FDA's decision on our pancreatic cancerapplication," said Colin Goddard, Ph.D., Chief Executive Officer ofOSI Pharmaceuticals. "Tarceva is the first new potential therapy innine years to have shown, in a randomized clinical trial, astatistically significant improvement in survival of patientssuffering from advanced pancreatic cancer, a disease with a very poorprognosis for most patients."

Pancreatic cancer has the highest one-year mortality rate of anycancer. The average life expectancy for a patient diagnosed withmetastatic pancreatic cancer is three to six months, according to ThePancreatic Cancer Action Network (PanCAN), a national patient advocacyorganization for the pancreatic cancer community.

"We are encouraged by the ODAC's recommendation as Tarcevarepresents a new advance in the struggle against pancreatic cancer.There is a tremendous need for new treatment options for thisdifficult-to-treat cancer," stated Hal Barron, M.D., Genentech'ssenior vice president, development and chief medical officer.

About the Study

The randomized Phase III clinical study of Tarceva, in combinationwith gemcitabine chemotherapy, met its primary endpoint of improvingsurvival. This international study was a multi-center, double-blind,placebo-controlled Phase III trial evaluating Tarceva in patients withunresectable locally advanced or metastatic pancreatic cancer. Thestudy randomized 569 patients to receive gemcitabine plus concurrentTarceva or gemcitabine plus placebo; 521 patients were randomized toreceive 100 mg/day of Tarceva or placebo, and 48 patients wererandomized to receive 150 mg/day of Tarceva or placebo. The ODACreview focused on the 100 mg/day cohort.

Compared to gemcitabine plus placebo, those patients receivinggemcitabine plus Tarceva 100 mg/day demonstrated a statisticallysignificant (23 percent) improvement in overall survival (hazard ratio= 0.81, p = 0.028), which can also be referred to as a 19 percentreduction in the risk of death. After one year, 23 percent of patientsreceiving Tarceva plus gemcitabine were alive compared to 17 percentof patients receiving gemcitabine plus placebo. A statisticallysignificant improvement in progression-free survival (hazard ratio =0.77; p = 0.006) was also demonstrated. Although no difference intumor response was observed (8.6 percent in patients receiving Tarcevaplus gemcitabine versus 7.9 percent in the gemcitabine plus placeboarm), the disease control rate (complete response + partial response +stable disease) was significantly improved (59 percent in patientsreceiving Tarceva plus gemcitabine versus 49 percent in thegemcitabine plus placebo arm, p = 0.036). Rash and diarrhea were theprincipal Tarceva-related side effects seen in the study and weregenerally characterized as mild-to-moderate.

Safety findings were generally consistent with previous studies ofTarceva in both monotherapy and combination settings. Rash wasreported in 69 percent of patients who received Tarceva plusgemcitabine and in 30 percent of patients who received gemcitabineplus placebo. Diarrhea was reported in 48 percent of patients whoreceived Tarceva plus gemcitabine and in 36 percent of patients whoreceived gemcitabine plus placebo. Two percent of the patientsdiscontinued Tarceva because of rash and two percent because ofdiarrhea. Possible interstitial lung disease (ILD) was experienced in2.3 percent of patients in the Tarceva plus gemcitabine arm comparedwith 0.4 percent in the gemcitabine plus placebo arm. The incidence ofserious ILD-like events in the Tarceva and gemcitabine arm was higherthan the 0.8 percent incidence reported for both the Tarcevamonotherapy and placebo arms in the Tarceva pivotal study in advancedNSCLC. The incidence of possible ILD from all clinical studies withTarceva is 0.7 percent.

About Pancreatic Cancer

According to the World Health Organization more than 216,000people worldwide are diagnosed each year with pancreatic cancer. TheAmerican Cancer Society predicts that in 2005 about 32,180 people inthe United States will be diagnosed with pancreatic cancer and about31,800 will die of the disease. Although pancreatic cancer accountsfor 2 percent of new cancer cases in the United States, it is thefourth leading cause of all cancer deaths. Most pancreatic tumorsoriginate in the exocrine duct cells or in the cells that producedigestive enzymes (acinar cells). Called adenocarcinomas, these tumorsaccount for nearly 95 percent of pancreatic cancers.

About Tarceva

Tarceva is an oral tablet currently approved for use in non-smallcell lung cancer (NSCLC) for those patients whose disease hasprogressed after one or more courses of chemotherapy. Tarceva is asmall molecule designed to target the human epidermal growth factorreceptor 1 (HER1) pathway, which is one of the factors critical tocell growth in a number of different cancer types. HER1, also known asEGFR, is a component of the HER signaling pathway, which plays a rolein the formation and growth of numerous cancers. Tarceva is designedto inhibit the tyrosine kinase activity of the HER1 signaling pathwayinside the cell, which may block tumor cell growth. Tarceva is theonly EGFR therapy to show in a Phase III trial improved survival foradvanced NSCLC patients. Additional early-stage trials of Tarceva arebeing conducted in other solid tumors. For Tarceva full prescribinginformation, please call 1-877-TARCEVA or visithttp://www.tarceva.com.

About OSI Pharmaceuticals

OSI Pharmaceuticals is committed to "shaping medicines andchanging lives" by discovering, developing and commercializinghigh-quality and novel pharmaceutical products that extend life orimprove the quality of life for cancer and diabetes patientsworldwide. The company operates through two business teams, (OSI)Oncology and (OSI) Prosidion. (OSI) Oncology is focused on developingmolecular targeted therapies designed to change the paradigm of cancercare. (OSI) Prosidion is committed to the generation of novel,targeted therapies for the treatment of type 2 diabetes and obesity.OSI's flagship product, Tarceva(R) (erlotinib), is the first drugdiscovered and developed by OSI to obtain FDA approval and the onlyEGFR inhibitor to have demonstrated the ability to improve survival inboth non-small cell lung cancer and pancreatic cancer patients. OSImarkets Tarceva through partnerships with Genentech, Inc. in the U.S.and with Roche throughout the rest of the world. For additionalinformation about OSI, please visit http://www.osip.com.

In addition to Tarceva, (OSI) Oncology exclusively marketsNovantrone(R) (mitoxantrone concentrate for injection) for itsapproved oncology indications and markets Gelclair(R) Bioadherent OralGel for the relief of pain associated with oral mucositis. Theresearch and development pipeline consists of novel molecularlytargeted anti-cancer agents focused on signal transduction pathwaysinvolved in cell proliferation, apoptosis and angiogenesis. The mostadvanced of these programs, targeting the co-inhibition of c-kit andVEGFR, has two candidates in development.

About Genentech BioOncology

Genentech is committed to changing the way cancer is treated byestablishing a broad oncology portfolio of innovative, targetedtherapies with the goal of improving patients' lives. The company isthe leading provider of anti-tumor therapeutics in the United States.Genentech is leading clinical development programs for Rituxan(R)(Rituximab), Herceptin(R) (Trastuzumab), Avastin(R) (bevacizumab) andTarceva(R) (erlotinib), and markets all four products in the UnitedStates alone (Avastin and Herceptin), with Biogen Idec Inc. (Rituxan)or with OSI Pharmaceuticals (Tarceva). Genentech has licensed Rituxan,Herceptin, and Avastin, and OSI Pharmaceuticals has licensed Tarcevato Roche for sale by the Roche Group outside of the United States.

The company has a robust pipeline of potential oncology therapieswith a focus on four key areas: angiogenesis, apoptosis (i.e.programmed cell death), the HER pathway and B-cell biology. Potentialoncology therapies directed at the HER pathway include a therapeuticantibody currently in Phase II trials. Also in early development are asmall molecule directed at the hedgehog pathway, a soluble humanprotein targeting apoptosis and a humanized anti-CD20 antibody forhematology/oncology indications.

Genentech is a leading biotechnology company that discovers,develops, manufactures and commercializes biotherapeutics forsignificant unmet medical needs. A considerable number of thecurrently approved biotechnology products originated from or are basedon Genentech science. Genentech manufactures and commercializesmultiple biotechnology products directly in the United States andlicenses several additional products to other companies. The companyhas headquarters in South San Francisco, California and is traded onthe New York Stock Exchange under the symbol DNA. For additionalinformation about the company, please visit http://www.gene.com.

For full prescribing information, including Boxed Warnings forAvastin, Rituxan and Herceptin, or for Tarceva full prescribinginformation, please call 800-821-8590 or visit www.gene.com.

Regarding OSI

This news release contains forward-looking statements. Thesestatements are subject to known and unknown risks and uncertaintiesthat may cause actual future experience and results to differmaterially from the statements made. Factors that might cause such adifference include, among others, the completion of clinical trials,the FDA review process and other governmental regulation, OSI's andits collaborators' abilities to successfully develop and commercializedrug candidates, competition from other pharmaceutical companies, theability to effectively market products, and other factors described inOSI Pharmaceuticals' filings with the Securities and ExchangeCommission.