Arizono H, Ishii S, Nagao T, Kudo S, Sasaki S, Kondo S, Kiyoki M
Pharmacological Research Department, Teijin Institute for Bio-Medical Research, Teijin Limited, Tokyo, Japan.
Arzneimittelforschung. 1994 Jul;44(7):890-8.
TI-23 consists of lyophilized regavirumab (monoclonal antibody C23, MCA C23), a new human monoclonal antibody against cytomegalovirus (CMV), human serum albumin (HSA) and amino acetic acid. The pharmacokinetics of MCA C23 was investigated in rats and rabbits. Plasma concentrations of radioactivity were shown to increase dose-dependently after 2, 10 or 50 mg/kg of 125I-labeled TI-23 was administered intravenously to rats. Their elimination of half-lives from plasma were 11-13 days. The radioactivity in plasma corresponded with the idiotype activity (antigenicity against idiotype antibody) of the monoclonal antibody. No significant difference was detected in plasma concentration and half-lives between male and female rats. Quantitative and qualitative distribution studies demonstrated that high radioactivity was distributed predominantly to the blood and blood-rich organs. The idiotype activity which remained in those tissues was attributable to the blood in the tissues. The radioactivity was mainly excreted in the urine as free iodine, and about 40% of the dose remained in the body. After the rabbits received 2 mg/kg of 125I-TI-23, the initial radioactivity in plasma was higher than in rats, and a larger distribution volume and shorter elimination half-lives of radioactivity in plasma were observed.
TI-23由冻干的瑞加韦单抗（单克隆抗体C23，MCA C23）、一种新型抗巨细胞病毒（CMV）人单克隆抗体、人血清白蛋白（HSA）和氨基乙酸组成。在大鼠和兔子身上研究了MCA C23的药代动力学。给大鼠静脉注射2、10或50mg/kg的125I标记的TI-23后，血浆放射性浓度呈剂量依赖性增加。它们从血浆中的消除半衰期为11-13天。血浆中的放射性与单克隆抗体的独特型活性（针对独特型抗体的抗原性）相对应。雄性和雌性大鼠的血浆浓度和半衰期未检测到显著差异。定量和定性分布研究表明，高放射性主要分布于血液和血运丰富的器官。那些组织中残留的独特型活性归因于组织中的血液。放射性主要以游离碘的形式经尿液排泄，约40%的剂量留在体内。兔子接受2mg/kg的125I-TI-23后，血浆中的初始放射性高于大鼠，并且观察到血浆中放射性的分布容积更大、消除半衰期更短。
