title: Quantification of Sorafenib in Human Serum by Competitive Enzyme-Linked Immunosorbent Assay.
abstract: The multikinase inhibitor sorafenib has been used in the treatment of hepatocellular carcinoma, renal cell carcinoma, and differentiated thyroid carcinoma. Here we have demonstrated the production of the first specific antibody against sorafenib. Anti-sorafenib serum was obtained by immunizing mice with an antigen conjugated with bovine serum albumin and carboxylic modified 4-(4-aminophenoxy)-N-methyl-2-pyridinecarboxamide (AMPC) using the N-succinimidyl ester method. Enzyme labeling of sorafenib with horseradish peroxidase was similarly performed using carboxylic modified AMPC. A simple competitive enzyme-linked immunosorbent assay (ELISA) for sorafenib was developed using the principle of direct competition between sorafenib and the enzyme marker for anti-sorafenib antibody, which had been adsorbed by the plastic surface of a microtiter plate. Serum sorafenib concentrations lower than 0.04 µg/mL were reproducibly measurable using the ELISA. This ELISA was specific to sorafenib and showed very slight cross-reactivity (2.5%) with a major metabolite, sorafenib N-oxide. The values of serum sorafenib levels from 32 patients measured by this ELISA were comparable with those measured by HPLC, and there was a strong correlation between the values determined by the two methods (Y=1.016X-0.137, r=0.979). The specificity and sensitivity of the ELISA for sorafenib should provide a valuable new tool for use in therapeutic drug monitoring and pharmacokinetic studies of sorafenib.
authors.affiliation: Applied Life Science Department, Faculty of Biotechnology and Life Science, Sojo University.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Saita
authors.forename: Yuta
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Noda
authors.forename: Makoto
authors.initials: M
authors.lastname: Shioya
authors.forename: Daiki
authors.initials: D
authors.lastname: Hira
authors.forename: Akira
authors.initials: A
authors.lastname: Andoh
authors.forename: Shin-Ya
authors.initials: SY
authors.lastname: Morita
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Terada
authors.forename: Masashi
authors.initials: M
authors.lastname: Shin
mesh_terms: D000818:Animals; D000906:Antibodies / Q000097:blood*; D000941:Antigens / Q000276:immunology; D000970:Antineoplastic Agents / Q000097:blood* / Q000276:immunology / Q000493:pharmacokinetics; D016903:Drug Monitoring; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006735:Horseradish Peroxidase / Q000276:immunology; D006801:Humans; D008807:Mice, Inbred BALB C; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000097:blood / Q000276:immunology / Q000493:pharmacokinetics; D010671:Phenylurea Compounds / Q000097:blood* / Q000276:immunology / Q000493:pharmacokinetics; D012710:Serum Albumin, Bovine / Q000276:immunology; D000077157:Sorafenib
chemical_list: D000906:Antibodies; D000941:Antigens; D000970:Antineoplastic Agents; D010671:Phenylurea Compounds; D009536:Niacinamide; D012710:Serum Albumin, Bovine; D000077157:Sorafenib; D006735:Horseradish Peroxidase