Pharmacokinetic and pharmacodynamic properties of methoxy polyethylene glycol-epoetin beta are unaffected by the site of subcutaneous administration.

C.E.R.A. (methoxy polyethylene glycol-epoetin beta), a continuous erythropoietin receptor activator, differs from traditional erythropoiesis-stimulating agents in its pharmacokinetic and receptor binding properties. This phase I, randomized, open-label, single-center, single-dose, 3-way crossover study in 42 healthy volunteers compared the pharmacokinetic and pharmacodynamic profile of C.E.R.A. 3.0 microg/kg after subcutaneous injection into the abdomen, arm, or thigh. The pharmacokinetic profile was similar at all 3 injection sites, with a prolonged apparent elimination half-life from 160 to 164 hours, area under the concentration-time curve from 4088 to 4323 ng.h/mL, and clearance/bioavailability from 0.64 to 0.68 mL/h/kg. C.E.R.A. produced a sustained erythropoietic response, and the pharmacodynamic profile (area under the reticulocyte count-time curve and maximum increase in reticulocyte count) was similar for all sites. C.E.R.A. was generally well tolerated, regardless of the administration site. This study suggests that C.E.R.A. has the potential to offer a choice of injection sites in clinical practice. The long half-life may permit effective anemia management with extended dosing intervals. Phase III clinical studies support the role of C.E.R.A. in managing anemia in patients with chronic kidney disease.

Pharmacokinetics and pharmacodynamics of intravenous and subcutaneous continuous erythropoietin receptor activator (C.E.R.A.) in patients with chronic kidney disease.

Continuous Erythropoietin Receptor Activator (C.E.R.A.) is a new agent that is in development for the treatment of anemia with extended administration intervals in patients who have chronic kidney disease (CKD), both those on and those not on dialysis. This was an open-label, randomized, multicenter, two-period, crossover study in erythropoiesis-stimulating agentnaïve patients who had CKD and anemia and were receiving peritoneal dialysis. After a 1-wk run-in period, 16 patients were randomly assigned to receive a single administration of intravenous C.E.R.A. 0.4 microg/kg (n = 8) or subcutaneous C.E.R.A. 0.8 microg/kg (n = 8). Six weeks after the first administration of C.E.R.A. (4-wk assessment, 2-wk washout), the route of administration was switched so that all patients received single administrations of both intravenous C.E.R.A. 0.4 microg/kg and subcutaneous C.E.R.A. 0.8 microg/kg. C.E.R.A. had a prolonged and comparable half-life after intravenous (mean 134 h) and subcutaneous (mean 139 h) administration. Reticulocyte counts peaked at a median of 8 d after intravenous and subcutaneous administration with no difference in the time course between administration routes. This resulted in similar mean values for the area under the reticulocyte count-time curve (1191 x 10(9) and 1193 x 10(9).d per L, respectively) and the maximum absolute increase in reticulocyte counts (36 x 10(9) and 41 x 10(9)/L, respectively). C.E.R.A. has a prolonged and comparable half-life after intravenous or subcutaneous injection, suggesting that extended administration intervals may be feasible in patients with CKD.