Eflapegrastim-xnst is a recombinant human granulocyte growth factor that binds to G-CSF receptors on myeloid progenitor cells and neutrophils, triggering signaling pathways that control cell differentiation, proliferation, migration and survival.
Eflapegrastim-xnst has been shown to elevate neutrophil counts in healthy subjects and in cancer patients. Absolute neutrophil count (ANC), Cmaxand area under the effect curve (AUEClast) increased with increasing doses of eflapegrastim-xnst in a linear, but less than dose-proportional, manner over a dose range of 45 to 350 mcg/kg.
The pharmacokinetics of eflapegrastim-xnst was studied in healthy subjects and patients with breast cancer. After subcutaneous (SC) dosing, the pharmacokinetics of eflapegrastim-xnst was nonlinear and exposure increases were not dose-proportional over the dose range of 45 to 350 mcg/kg.
The median Tmax of eflapegrastim-xnst is 25 hours (6 to 144 hours) in patients with breast cancer following administration of the recommended dosage.
The volume of distribution of eflapegrastim-xnst is 1.44 L.
The geometric mean half-life of eflapegrastim-xnst in patients with breast cancer is 36.4 hours (Range: 16.1 to 115 hours) during Cycle 1. Eflapegrastim-xnst clearance decreased with increasing doses following single dose administration, suggesting target-mediated clearance of eflapegrastim-xnst by neutrophils. Following repeat administration, clearance increased in Cycle 3 as compared to Cycle 1, potentially due to the subsequent increase in neutrophils. In in vitro studies, the IgG4 Fc fragment in eflapegrastim-xnst binds to the neonatal Fc receptor (FcRn), facilitating the FcRn-mediated transcytosis of eflapegrastim-xnst.
Eflapegrastim-xnst is expected to be metabolized by endogenous degradation following receptor-mediated internalization by cells bearing the G-CSF receptor.
Eflapegrastim-xnst was not detected in urine.
No studies evaluating the drug interaction potential of eflapegrastim-xnst have been conducted.
© All content on this website, including data entry, data processing, decision support tools, "RxReasoner" logo and graphics, is the intellectual property of RxReasoner and is protected by copyright laws. Unauthorized reproduction or distribution of any part of this content without explicit written permission from RxReasoner is strictly prohibited. Any third-party content used on this site is acknowledged and utilized under fair use principles.
