DETERMINATION OF MK-852, A NEW FIBRINOGEN RECEPTOR ANTAGONIST, IN PLASMA AND URINE BY RADIOIMMUNOASSAY

MK-852 is a novel fibrinogen receptor antagonist. A sensitive and spec ific radioimmunoassay has been developed for the determination of this drug candidate in plasma and urine. The immunogen was prepared by cou pling to albumin via a dinitrophenylene bridge and the radioligand by reaction of the drug with the I-125-labelled Bolton-Hunter reagent. Th e method was specific and no immunoreactive material other than parent drug was detectable in plasma from dosed volunteers. The direct assay using 0.05 ml of plasma is sensitive to 0.2 ng ml-1 without matrix in terference and has sufficient sensitivity, precision, accuracy, and se lectivity for the analysis of clinical samples. The lower quantifiable limit in (diluted) urine is 50 ng ml-1.