Phase 3 Study Shows Majority of Neutropenia with Related Fever and Hospitalization Occurs in First Treatment Cycle for Breast Cancer Patients Not Receiving Neulasta

The Largest Randomized Placebo-Controlled Study to Date for Neulasta Supports First and Subsequent Cycle Administration

THOUSAND OAKS, Calif.--(BUSINESS WIRE)--Dec. 10, 2004-- Amgen Inc. (Nasdaq:AMGN), the world's largest biotechnology company, today announced that new data from a Phase 3 study show that the majority of neutropenic complications occur in the first cycle of chemotherapy treatment for breast cancer patients who are not administered Neulasta(R) (pegfilgrastim). The study found that administering Neulasta beginning in the first and subsequent cycles of chemotherapy reduced the rate of infection, as manifested by febrile neutropenia (low white blood cell count with fever), by more than 90 percent. Hospitalization and the use of intravenous anti-infectives in breast cancer patients were also significantly lower in the group receiving Neulasta in the first and subsequent cycles of chemotherapy. The results were presented by the study's lead investigator, Charles Vogel, M.D., Cancer Research Network, Plantation, Fla., at the 27th Annual San Antonio Breast Cancer Symposium (SABCS). (SABCS Abstract # 5044)

"Patients in the placebo arm not only experienced significantly more neutropenic events than patients in the Neulasta arm, but more than 65 percent of these events occurred in the first cycle of treatment, emphasizing the importance of early protection," said Dr. Vogel. "This study suggests that Neulasta used in first and subsequent cycles of chemotherapy achieves maximum clinical benefit."

Febrile (or feverish) neutropenia is the most common presentation of infection in patients receiving chemotherapy. Infection in this setting can be serious and even life threatening because chemotherapy can compromise the patient's ability to fight infection.

Breast cancer patients (Stage 1-4, ECOG performance of 0-2) receiving 100 mg/m(2) docetaxel every three weeks for up to four cycles were randomized to receive either 6 mg Neulasta (n=463) or placebo (n=465) once-per-cycle on the day after docetaxel administration for up to four cycles. Docetaxel is associated with an average reported febrile neutropenia incidence of approximately 10 to 20 percent in the absence of growth factor support. Febrile neutropenia was defined as fever with a temperature equal to or greater than 38.2 degrees C and an absolute neutrophil count (ANC) less than 0.5 x 10(9)/L measured the same day or the day after fever was documented.

First-cycle administration of Neulasta resulted in a 91 percent reduction in the incidence of febrile neutropenia occurring in the first cycle of chemotherapy; an 89 percent reduction in the incidence of hospitalization and an 83 percent reduction in the incidence of intravenous anti-infective use.

Specifically, in the first cycle, one percent of patients in the Neulasta arm (2/463) developed febrile neutropenia compared with 11 percent of patients in the placebo arm (52/465). Neulasta was also associated with a significantly lower incidence of hospitalizations with one percent of patients requiring hospitalization (5/463) in the first cycle versus nine percent of patients receiving placebo (43/465). One percent of patients in the Neulasta arm (5/463) required intravenous anti-infectives in the first cycle versus six percent of patients in the placebo arm (30/465).

In addition, in cycles two through four, less than one percent of patients in the Neulasta arm (1/458) developed febrile neutropenia compared with six percent of patients in the placebo arm (26/454). During these cycles, less than one percent of patients in the Neulasta arm (1/458) were hospitalized versus five percent in the placebo arm (21/454). Less than one percent of patients in the Neulasta arm (3/458) required intravenous anti-infectives in the subsequent cycles compared to four percent in the placebo arm (19/454).

Neulasta was well tolerated in this study with an adverse event profile similar to placebo. Bone pain was a frequently observed adverse event in both arms of the study (31 percent with Neulasta versus 27 percent with placebo).

About Neulasta

Neulasta was approved by the U.S. Food and Drug Administration (FDA) in 2002 for decreasing the incidence of infection, as manifested by neutropenia, in patients with nonmyeloid malignancies receiving myelosuppressive anticancer drugs associated with a clinically significant incidence of febrile neutropenia. Similar indications for Neulasta were approved in Europe and Australia the same year.

Rare cases of splenic rupture and sickle cell crises have been reported in postmarketing experience. Allergic reactions, including anaphylaxis, have also been reported. The majority of these reactions occurred upon initial exposure. However, in rare cases, allergic reactions, including anaphylaxis, recurred within days after discontinuing anti-allergic treatment. In clinical trials, the only serious adverse event not attributed to the underlying disease or chemotherapy was a case of hypoxia. The most common adverse event attributed to Neulasta was bone pain, reported in 26 percent of patients. While not reported in patients receiving Neulasta, rare events of adult respiratory distress syndrome have been reported in patients receiving the parent compound, Filgrastim.

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SOURCE: Amgen Inc.