Abstract: The invention teaches derivatives of ascomycin and methods of preparing immunogens and other conjugates useful in immunoassays for quantitatively measuring concentrations of tacrolimus in patient specimens. Antibodies produced from the disclosed immunogens capable of binding to tacrolimus with cross-reactivity of no more than 5% with each of 15-O-demethyl tacrolimus, 31-O-demethyl tacrolimus, and 13,31-O-didemethyl tacrolimus, less than 40% with 13-O-demethyl tacrolimus, and less than 1% with cyclosporin, rapamycin, mycophenolic acid, prednisone, hydrocortisol, and prednisolone are described. Further, immunoassays for measuring the concentration of tacrolimus using such antibodies are taught.

Abstract: Ethyl glucuronide (“EtG”) analogs can be prepared for use as immunodiagnostic reagents and in immunodiagnostic protocols. The EtG analogs can be in the form of EtG-based immunogens, and EtG-based antigens. The EtG-based immunogens can be used for preparing anti-EtG antibodies, which can be used in immunoassays. Accordingly, improved immunoassay techniques for detecting EtG can be performed with the EtG-based antigens, and anti-EtG antibodies prepared from EtG-based immunogens.

Abstract: The invention teaches derivatives of mycophenolic alcohol and methods of preparing immunogens and other conjugates useful in immunoassays for quantitatively measuring concentrations of mycophenolic acid (MPA) and/or active metabolites of MPA in patient specimens. Antibodies produced from the disclosed immunogens capable of binding to MPA with cross-reactivity of no more than 5% with inactive metabolites and commonly co-prescribed drugs. Further, immunoassays for measuring the concentration of MPA using such antibodies are taught.

Abstract: The invention teaches derivatives of ascomycin and methods of preparing immunogens and other conjugates useful in immunoassays for quantitatively measuring concentrations of tacrolimus in patient specimens. Antibodies produced from the disclosed immunogens capable of binding to tacrolimus with cross-reactivity of no more than 5% with each of 15-O-demethyl tacrolimus, 31-O-demethyl tacrolimus, and 13,31-O-didemethyl tacrolimus, less than 40% with 13-O-demethyl tacrolimus, and less than 1% with cyclosporin, rapamycin, mycophenolic acid, prednisone, hydrocortisol, and prednisolone are described. Further, immunoassays for measuring the concentration of tacrolimus using such antibodies are taught.