Pegfilgrastim as hematopoietic support for dose-dense chemoimmunotherapy with R-CHOP-14 as first-line therapy in elderly patients with diffuse large B cell lymphoma.

Goals Of Work: Recently, 6 cycles of R-CHOP-14 have been recommended as the reference standard regimen for the treatment of elderly patients with diffuse large B-cell lymphoma (DLBCL). Pegfilgrastim has been shown to facilitate dose-dense chemotherapy schedules with a single administration per chemotherapy cycle. The aims of this study were to evaluate the use of pegfilgrastim in combination with the R-CHOP-14 regimen in a homogenous group of previously untreated elderly patients with DLBCL and to assess the pharmacokinetics of pegfilgrastim within this patient population.

Materials And Methods: Ten patients with DLBCL between 60 and 80 years of age received a single subcutaneous injection of 6 mg pegfilgrastim 24 h after administration of R-CHOP chemoimmunotherapy, which was repeated for 6 to 8 cycles in two-weekly intervals. A total of 348 blood samples were collected. Pegfilgrastim plasma levels and absolute neutrophil counts were measured every other day during the first treatment cycle and twice weekly during all consecutive cycles.

Main Results: Sixty-three of 72 cycles (87.5%) could be delivered on time and at the planned dose. Median absolute neutrophil nadir was 0.32 g/l on day 9. Grade 3/4 granulocytopenia occurred in all patients. Febrile neutropenia occurred in two patients. Plasma levels of pegfilgrastim remained elevated during the neutropenic phase. At the start of hematologic recovery, plasma concentrations of pegfilgrastim decreased rapidly to baseline levels. Median pegfilgrastim trough plasma level was 0.43 ng/ml on the day preceding the next application.

Conclusions: A single fixed dose of 6 mg of pegfilgrastim given once per cycle of R-CHOP-14 is effective in supporting neutrophil recovery to allow two-weekly drug administration in previously untreated elderly patients with DLBCL. However, close monitoring for infectious complications is mandatory in this patient population.