An overview of the efficacy and safety of novel erythropoiesis stimulatingprotein (NESP)

Novel erythropoiesis stimulating protein (NESP, also known as darbepoetin a lfa) is a molecule that stimulates erythropoiesis by the same mechanism as both native and recombinant human erythropoietin (rHuEPO). The extra sialic residues on NESP, however, allow it to be more stable in vivo with a 2- to 3-fold longer elimination half-life. Thus, following intravenous administr ation, the mean elimination half-life of NESP is 25.3 vs 8.5 h for rHuEPO. After subcutaneous administration, the mean terminal half-life for NESP is 48.8 h. The mean bioavailability of NESP after subcutaneous administration is similar to 37%, similar to that reported for rHuEPO. The pharmacokinetic data suggested that patients with renal anaemia would require less frequen t dosing with NESP than with rHuEPO. NESP 0.45 mug/kg administered once wee kly either intravenously or subcutaneously has been evaluated for the corre ction of chronic renal failure (CRF)associated anaemia. The study populatio n included CRF patients not receiving dialysis, along with those on haemodi alysis or peritoneal dialysis. In patients who are rHuEPO-naive, NESP has a similar effect in correcting the anaemia as is seen with rHuEPO, but with less frequent dosing. Similarly, in patients previously receiving rHuEPO, N ESP (whether administered intravenously or subcutaneously) is as effective as rHuEPO treatment for maintaining haemoglobin concentration when administ ered at a reduced frequency (i.e. either once weekly or once every other we ek). NESP is well tolerated, adverse effects are similar to those seen with rHuEPO, and no antibodies have been detected in > 1500 patients exposed to NESP thus far.