PIII‐73

BACKGROUND/AIMS Continuous Erythropoietin Receptor Activator (CERA), an innovative erythropoiesis stimulating agent, acting differently at the receptor level and with prolonged half‐life, is in development to provide correction of anemia at extended administration intervals. The study objectives were to describe and compare the pharmacokinetics (PK) and pharmacodynamics (PD) of CERA after subcutaneous (SC) administration using 3 different sites (abdomen, arm and thigh). METHODS An open‐label, randomized, single‐center, single‐dose, 3‐way crossover study in 42 healthy volunteers (HV) examined the PK and PD of CERA. Each subject received 3 single administrations of CERA 3.0 μg/kg (one at each site: abdomen, arm and thigh) with a 7‐week washout period between each injection. RESULTS The AUC last (primary PK parameter) was similar for the 3 sites of administration and the ratios of the geometric least square means[90% Confidence Interval] were 1.01[0.9 – 1.13], 1.11[1.01 – 1.22] and 1.1[1.02 – 1.18] when comparing abdomen to arm, thigh to arm and thigh to abdomen. For C max , the ratios and their 90% CI were 1.09[0.95 – 1.25], 1.21[1.07 – 1.37] and 1.11[1.02 – 1.22], respectively. The increase in mean reticulocyte count was similar for the 3 sites of SC injection. For AUE 1–50days , mean values were similar for the 3 sites (ratios between 1.00 and 1.05). CONCLUSION The site of subcutaneous injection (abdomen, arm or thigh) has no clinically relevant effect on the pharmacokinetics and pharmacodynamics of CERA. Clinical Pharmacology & Therapeutics (2005) 79 , P78–P78; doi: 10.1016/j.clpt.2005.12.281