EXHIBIT 99

             TARCEVA PLUS GEMCITABINE IMPROVES SURVIVAL COMPARED TO
           GEMCITABINE ALONE IN FIRST-LINE PANCREATIC CANCER PATIENTS

      MELVILLE, N.Y. & SOUTH SAN FRANCISCO, Calif. & BASEL, Switzerland--Sept.
20, 2004--OSI Pharmaceuticals, Inc. (Nasdaq:OSIP), Genentech, Inc. (NYSE: DNA),
and Roche (SWX Zurich) announced today that results from a randomized Phase III
clinical study of the investigational drug Tarceva(TM) (erlotinib HCl), in
combination with gemcitabine chemotherapy met its primary endpoint of improving
survival. The international study demonstrated a statistically significant 23.5
percent improvement in overall survival for patients with locally advanced or
metastatic pancreatic cancer when compared to patients receiving gemcitabine
plus placebo. A hazard ratio of 0.81 and a p-value of 0.025 were observed (a
hazard ratio of less than one indicates a reduction in the risk of death and a
p-value of less than 0.05 indicates statistical significance). Median and
one-year survival in the Tarceva(TM) plus gemcitabine arm were 6.4 months and
25.6 percent respectively compared to 5.9 months and 19.7 percent in the
gemcitabine plus placebo arm. A statistically significant improvement in
progression-free survival was also demonstrated, although no difference in tumor
response was observed. A preliminary analysis of the safety data did not reveal
any unexpected safety signal beyond that seen in prior use of Tarceva(TM) in
both monotherapy and combination settings. As expected, rash and diarrhea were
the principal Tarceva(TM) related side effects seen in the study.

      Tarceva(TM) is a small molecule oral therapy designed to inhibit the
tyrosine kinase activity of the HER1/EGFR signaling pathway inside the cell,
which may block tumor growth. This study, which was sponsored by OSI, was
coordinated by the National Cancer Institute of Canada Clinical Trials Group at
Queens University. Results from the study will be submitted for presentation at
an appropriate peer-reviewed oncology meeting in the near future.

      "The results of this trial of Tarceva(TM) in combination with gemcitabine
represent an important advancement in treating patients with pancreatic cancer,"
stated Malcolm Moore, M.D., Study Chair and Medical Oncologist at Princess
Margaret Hospital and Chair of the Gastrointestinal Disease Site, NCIC Clinical
Trials Group. "Pancreatic cancer is widely recognized as a difficult disease to
treat and new therapeutic regimens are desperately needed. These results also
demonstrate that the HER1/EGFR signaling pathway is an important target in
pancreatic cancer, and offer hope that further progress can be made."

      "The positive outcome of this study is great news for pancreatic cancer
patients and their families and adds to our growing understanding of the broad
potential utility of Tarceva," said Colin Goddard, Ph.D., Chief Executive
Officer of OSI Pharmaceuticals. "The results represent an important
demonstration of Tarceva's activity beyond non-small cell lung cancer, and
building on the results of our monotherapy studies in lung cancer, will support
our ongoing efforts to further optimize the dosing and scheduling of Tarceva for
the treatment of both pancreatic cancer and other cancers."


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      "These data are important in that they open the door to a completely new
approach in the treatment of pancreatic cancer, a disease in which currently
only 20 percent of patients survive one year after diagnosis," said Hal Barron,
M.D., Genentech's senior vice president, development and chief medical officer.
"We will work closely with our collaborators to continue to understand these
data, as well as determine additional clinical studies to optimize the potential
use of Tarceva in this disease setting. The alliance will discuss these data
with the FDA and other regulatory agencies to determine the next steps for
Tarceva in pancreatic cancer."

      In July 2004, OSI completed the submission of a New Drug Application (NDA)
with the FDA for Tarceva(TM), as a monotherapy for the treatment of patients
with advanced non-small cell lung cancer (NSCLC) after failure of at least one
standard chemotherapy regimen.

About the Study

      This was a multi-center, randomized, double-blind, placebo-controlled
Phase III study evaluating Tarceva(TM) at 100 mg/day or 150 mg/day in patients
with locally advanced or metastatic pancreatic cancer. The study randomized
patients to receive either gemcitabine plus concurrent Tarceva(TM) or
gemcitabine plus placebo. A total of 569 patients were randomized in the study,
521 patients in the group who received 100 mg/day of Tarceva(TM) or placebo, and
48 patients in the group who received 150 mg/day of Tarceva(TM) or placebo. The
study was an international study with sites in the United States, Asia, Canada,
Europe, Australia and South America.

About Pancreatic Cancer

      According to the World Health Organization more than 216,000 people
worldwide are diagnosed each year with pancreatic cancer. The American Cancer
Society predicts that in 2004 about 31,860 people in the United States will be
found to have pancreatic cancer and about 31,270 will die of the disease. Most
pancreatic tumors originate in the exocrine duct cells or in the cells that
produce digestive enzymes (acinar cells). Called adenocarcinomas, these tumors
account for nearly 95 percent of pancreatic cancers.

About Tarceva(TM)

      Tarceva(TM) is designed to block tumor cell growth by inhibiting the
tyrosine kinase activity of the HER1/EGFR receptor thereby blocking the
HER1/EGFR signaling pathway inside the cell. Tarceva(TM) is currently being
evaluated in an extensive clinical development program by a global alliance
among OSI Pharmaceuticals, Genentech, and Roche.

      In April 2004, the alliance announced that Tarceva(TM) extended survival
of patients receiving monotherapy Tarceva(TM) in a large randomized Phase III
study in patients with advanced non-small cell lung cancer (NSCLC) after failure
of at least one standard chemotherapy regimen. Tarceva(TM) is the first and only
targeted therapy to demonstrate an improvement in survival for advanced NSCLC
patients. Detailed results of the trial were presented in June at the 40th
Annual American Society of Clinical Oncology (ASCO) meeting in New Orleans.

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      The NDA was granted Pilot 1 Status under the FDA's Pilot 1 Program for
Continuous Marketing Applications, a new program designed for investigational
products that have been given Fast Track status such as Tarceva(TM), and that
have demonstrated significant promise in clinical trials as a therapeutic
advance over available therapy for a disease or condition. In addition, Roche
recently submitted a marketing Authorization Application to the European health
authorities for Tarceva(TM) for the monotherapy treatment of advanced NSCLC.

About OSI Pharmaceuticals

      OSI Pharmaceuticals is a leading biotechnology company focused on the
discovery, development, and commercialization of high-quality, next-generation
oncology products that both extend life and improve the quality of life for
cancer patients worldwide. OSI has a balanced pipeline of oncology drug
candidates that includes both novel mechanism-based, gene-targeted therapies
focused in the areas of signal transduction and apoptosis and a next-generation
cytotoxic chemotherapy agent. OSI's most advanced drug candidate, Tarceva(TM), a
small-molecule inhibitor of the HER1 gene, has successfully completed Phase III
clinical trials for lung cancer and is the subject of an ongoing New Drug
Application (NDA). OSI has a commercial presence in the U.S. oncology market
where it exclusively markets Novantrone(R) (mitoxantrone concentrate for
injection) for approved oncology indications and Gelclair(R) for the relief of
pain associated with oral mucositis. OSI has also established Prosidion Limited,
an independently operated diabetes and obesity subsidiary based in the United
Kingdom.

About Genentech BioOncology

      Genentech is committed to changing the way cancer is treated by
establishing a broad oncology portfolio of innovative, targeted therapies with
the goal of improving patients' lives. The company is the leading provider of
anti-tumor therapeutics in the United States. Genentech is leading clinical
development programs for Rituxan(R) (Rituximab), Herceptin(R) (Trastuzumab), and
Avastin(TM) (bevacizumab) and markets all three products in the United States
either alone (Avastin, which it recently launched in the United States, and
Herceptin) or with Biogen Idec Inc. (Rituxan). Genentech has licensed Rituxan,
Herceptin and Avastin to Roche for sale by the Roche Group outside of the United
States.

      The company has a robust pipeline of potential oncology therapies with a
focus on four key areas: angiogenesis, apoptosis (i.e. programmed cell death),
the HER pathway and B-cell biology. Potential oncology therapies directed at the
HER pathway include Tarceva(TM) (erlotinib HCl) and a therapeutic antibody
currently in Phase II trials. Also in early development are a small molecule
directed at the hedgehog pathway, a therapy targeting apoptosis and a humanized
anti-CD20 antibody for hematology/oncology indications.

      Genentech is a leading biotechnology company that discovers, develops,
manufactures and commercializes biotherapeutics for significant unmet medical
needs. A considerable number of the currently approved biotechnology products
originated from or are based on Genentech science. Genentech manufactures and
commercializes multiple biotechnology products directly in the United States and
licenses several additional products to other companies. The company has

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headquarters in South San Francisco, California and is traded on the New York
Stock Exchange under the symbol DNA. For press releases and additional
information about the company, please visit http://www.gene.com.

Roche in Oncology

      Within the last five years the Roche Group including its partners
Genentech in the US and Chugai in Japan has become the world's leading provider
of anti-cancer treatments, supportive care products and diagnostics. Its
oncology business includes an unprecedented four marketed products with survival
benefit in different major tumour indications: Xeloda and Herceptin in advanced
stage breast cancer, MabThera in non-Hodgkin's lymphoma, and Avastin in
colorectal carcinoma. In the United States Herceptin, MabThera and Avastin are
marketed either by Genentech alone or together with Biogen Idec Inc. Outside of
the United States, Roche and its Japanese partner Chugai are responsible for the
marketing of these drugs.

      The Roche oncology portfolio also includes NeoRecormon (anaemia in various
cancer settings), Bondronat (prevention of skeletal events in breast cancer and
bone metastases patients, hypercalcaemia of malignancy), Kytril (chemotherapy
and radiotherapy-induced nausea and vomiting) and Roferon-A (hairy cell and
chronic myeloid leukaemia, Kaposi's sarcoma, malignant melanoma, renal cell
carcinoma). CERA is the most recent demonstration of the commitment to anaemia
management. The Roche Group's cancer medicines generated sales of more than 3.3
billion Swiss francs in the first half of 2004.

      Roche is developing new tests, which will have a significant impact on
disease management for cancer patients in the future. With a broad portfolio of
tumour markers for prostate, colorectal, liver, ovarian, breast, stomach,
pancreas and lung cancer, as well as a range of molecular oncology tests, we
will continue to be the leaders in providing cancer focused treatments and
diagnostics.

      Roche Oncology has four research sites (two in the US, Germany and Japan)
and four Headquarter Development sites (two in the US, UK and Switzerland).

Regarding OSI

      This news release contains forward-looking statements. These statements
are subject to known and unknown risks and uncertainties that may cause actual
future experience and results to differ materially from the statements made.
Factors that might cause such a difference include, among others, the completion
of clinical trials, the FDA review process and other governmental regulation,
OSI's and its collaborators' abilities to successfully develop and commercialize
drug candidates, competition from other pharmaceutical companies, the ability to
effectively market products, and other factors described in OSI Pharmaceuticals'
filings with the Securities and Exchange Commission. Tarceva(TM) is an
investigational compound and has not yet been approved as safe or efficacious in
humans for its ultimate intended use.

    CONTACT: OSI Media and Investor Contact
             Kathy Galante, 631-962-2000


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             or
             GNE Media Contact
             Kristina Becker, 650-467-6450
             or
             GNE Investor Contact
             Lisa Tuomi, 650-225-6554



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