Opinion Based on Positive Benefit / Risk Assessment in Patients with Metastatic Colorectal Cancer with Non-Mutated KRAS

THOUSAND OAKS, Calif.--(BUSINESS WIRE)--Sept. 21, 2007--Amgen (NASDAQ:AMGN) today announced that the European Committee for Medicinal Products for Human Use (CHMP) has issued a positive opinion recommending a conditional marketing authorization for Vectibix(TM) (panitumumab) in the European Union (EU) for patients with refractory metastatic colorectal cancer with non-mutated (wild-type) KRAS genes.

"We are pleased that Vectibix has received a positive opinion for conditional approval so patients in the EU have further treatment options for metastatic colorectal cancer," said Willard Dere, M.D., senior vice president and international chief medical officer at Amgen. "This is an important step forward in personalized cancer care. Amgen is committed to discovering, validating and implementing novel clinically relevant biomarkers to help physicians provide the right treatment for patients."

The CHMP positive opinion for Vectibix is based on a positive benefit / risk assessment in a patient population that currently has few treatment options available to them. As part of the CHMP review, clinical data supporting the utility of KRAS mutation status as a biomarker for clinical outcome were provided. These data were evaluated in combination with the overall clinical benefit observed in the pivotal "408" study and safety database available. The KRAS data will be presented for the first time at the 14th European Cancer Conference, Barcelona, on September 25th in the Presidential Symposium.

KRAS plays an important role in cell growth regulation and oncogenesis. Anti-epidermal growth factor receptor (EGFR) therapies work by blocking the activation of EGFR, thereby inhibiting downstream events that lead to malignant signaling. However, in patients with tumors harboring a mutated or activated KRAS, the KRAS protein is always turned "on" regardless of whether EGFR has been activated or therapeutically inhibited. Thus, in patients with mutated KRAS, signaling continues despite anti-EGFR therapy. Mutant KRAS is detected in approximately 40 percent of mCRC.

About Vectibix

Vectibix (panitumumab) the first fully human IgG2 monoclonal antibody (MAb), targets the epidermal growth factor receptor (EGFr), a protein that plays an important role in cancer cell signalling. With its demonstrated efficacy, low rate of infusion reactions and immunogenicity, and convenient Q2W dosing schedule Vectibix provides an important option in the management of metastatic CRC patients. Ongoing Phase 3 trials are exploring the potential of administering Vectibix in combination with chemotherapy for first- and second-line mCRC.

Approved by the FDA in September 2006 Vectibix is indicated for the treatment of patients with epidermal growth factor receptor (EGFr) expressing metastatic colorectal cancer after disease progression on, or following fluoropyrimidine, oxaliplatin and irinotecan containing chemotherapy regimens. The effectiveness of Vectibix for the treatment of metastatic colorectal carcinoma is based on progression-free survival. Currently no data are available that demonstrate an improvement in disease related symptoms or increased survival with Vectibix.

In the EU, Vectibix is indicated as monotherapy for the treatment of patients with metastatic colorectal carcinoma expressing EGFR with non-mutated KRAS tumours and after failure of fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy regimens.

Important Product Safety Information - U.S.

Dermatologic toxicities, related to Vectibix blockade of EGF binding and subsequent inhibition of EGF receptor-mediated signalling pathways, included but were not limited to dermatitis acneiform, pruritus, erythema, rash, skin exfoliation, paronychia, dry skin and skin fissures. Dermatologic toxicities were reported in 89 percent of patients treated with Vectibix and were severe in 12 percent of patients. Severe dermatologic toxicities were complicated by infection, including sepsis, septic death and abscesses requiring incisions and drainage. Vectibix may need to be withheld or discontinued for severe dermatologic toxicities.

Severe infusion reactions occurred with Vectibix in approximately one percent of patients. Severe infusion reactions were identified as anaphylactic reactions, bronchospasm, fever, chills and hypotension. Although fatal infusion reactions have not been reported with Vectibix, they have occurred with other monoclonal antibody products. Severe infusion reactions require stopping the infusion and possibly permanently discontinuing Vectibix, depending on the severity and / or persistence of the reaction.

About Amgen

Amgen discovers, develops and delivers innovative human therapeutics. A biotechnology pioneer since 1980, Amgen was one of the first companies to realise the new science´s promise by bringing safe, effective medicines from lab, to manufacturing plant, to patient. Amgen therapeutics has changed the practice of medicine, helping millions of people around the world in the fight against cancer, kidney disease, rheumatoid arthritis, and other serious illnesses. With a deep and broad pipeline of potential new medicines, Amgen remains committed to advancing science to dramatically improve people´s lives. To learn more about our pioneering science and our vital medicines, visit www.amgen.com.

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CONTACT: Amgen Sabeena Ahmad, + 41 41 3692 530 (EU media) Christine Regan, 805-447-5476 (media, oncology) Arvind Sood, 805-447-1060 (investors) SOURCE: Amgen