Neutropenic events in community practices reduced by first and subsequent cycle pegfilgrastim use

The impact of first- and subsequent-cycle growth factor use in the community setting has not been studied extensively. We conducted this large, prospective, noncomparative study to assess neutropenia and related complications in patients receiving myelotoxic chemotherapy with pegfilgrastim support in community practices. Patients ≥18 years old with cancers other than leukemia or myelodysplastic syndrome, including those with major comorbidities, were eligible. Pegfilgrastim (6 mg) was to be administered ∼24 hours after chemotherapy in all cycles (minimum, four cycles). A total of 2,112 patients was included in the analyses. The most common tumor types were breast cancer (46%), non-Hodgkin's lymphoma (15%), and non-small cell lung cancer (13%). Chemotherapies administered most often were a platinum plus a taxane (18%), and anthracycline plus an alkylating agent (18%), and a taxane plus an anthracycline plus an alkylating agent (16%). The percentage of patients with neutropenia-related hospitalization was 2.9% in cycle 1 and 5.6% across all cycles. Chemotherapy dose reductions and delays were attributed to neutropenia in 1.8% and 0.9% of patients, respectively, in cycle 2 and 2.9% and 2.1% of patients, respectively, across all cycles. Febrile neutropenia (absolute neutrophil count <1.0 × 10⁹/l with temperature ≥38.2°C) occurred in 3.6% of patients in cycle 1 and in 6.3% of patients across all cycles. The most frequently reported serious adverse events were febrile neutropenia (3.4%), neutropenia (2.6%), and dehydration (2.6%). Bone pain (0.1%) was the only related serious adverse event reported in more than one patient. Data from this communitybased study suggest that patients undergoing chemotherapy benefit from pegfilgrastim support beginning in the first cycle of chemotherapy.