Site-Specific Conjugation of Monomethyl Auristatin E to Anti-CD30 Antibodies Improves Their Pharmacokinetics and Therapeutic Index in Rodent Models
Site-Specific Conjugation of Monomethyl Auristatin E to Anti-CD30 Antibodies Improves Their Pharmacokinetics and Therapeutic Index in Rodent Models
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DOI：
10.1021/mp500666j
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发表时间：
2015-06-01
影响因子：
4.9
通讯作者：
Romagne, F.
中科院分区：
文献类型：
--
作者：
Lhospice, F.;Bregeon, D.;Romagne, F.
抗体-药物偶联物（adc）已显示出临床益处，导致最近FDA批准了KADCYLA和ADCETRIS。目前临床使用或开发的大多数adc，包括ADCETRIS，都是通过赖氨酸或半胱氨酸残基对毒素进行化学偶联产生的，这不可避免地导致了具有可变药抗体比（dar）的异质产物。在这里，我们描述了四种基于抗cd30抗体cAC10的新型adc的体外和体内特性，它们与ADCETRIS具有相同的多肽主链，并将结果与后者进行了比较。利用细菌转谷氨酰胺酶（BTG）在cAC10的295位和297位特异性地偶联单甲基auristatin E的衍生物（均含有可切割的连接物），从而得到DAR为4的均匀adc。使用两种不同的cd30阳性细胞系（Karpas 299和Raji-CD30(+)）进行的体外细胞毒性实验显示，ADCETRIS（分别为1.8 +/- 0.4和3.6 +/- 0.6 ng/mL）和四种基于cac10的adc（2.0 +/- 0.4至4.9 +/- 1.0 ng/mL）的EC50值相当。在正常和异种移植（Karpas 299细胞）SCID小鼠体内进行定量的时间依赖性生物分布研究（3-96小时），选择i -125放射性碘化cAC10 ADC，并与I-125-ADCETRIS进行比较。化学酶偶联的放射碘化ADC显示出更高的肿瘤摄取（17.84 +/- 2.2% ID/g 24 h p.i.）比I-125-ADCETRIS （10.5 +/- 1.8% ID/g 24 h p.i.）。此外，（125）I-ADCETRIS表现出更高的非靶向肝脏和脾脏摄取。与这些结果一致，btg偶联ADC在大鼠中的最大耐受剂量（bbb60 mg/kg）显著高于ADCETRIS （18 mg/kg）。这些结果表明，与具有可变dar的化学修饰adc相比，均质adc具有更好的药代动力学和更好的治疗指标。
Antibody-drug conjugates (ADCs) have demonstrated clinical benefits that have led to the recent FDA approval of KADCYLA and ADCETRIS. Most ADCs that are currently in clinical use or development, including ADCETRIS, are produced by chemical conjugation of a toxin via either lysine or cysteine residues, inevitably leading to heterogeneous products with variable drug-to-antibody ratios (DARs). Here, we describe the in vitro and in vivo characterization of four novel ADCs that are based on the anti-CD30 antibody cAC10, which has the same polypeptide backbone as ADCETRIS, and compare the results with the latter. Bacterial transglutaminase (BTG) was exploited to site-specifically conjugate derivatives of monomethyl auristatin E (all comprising a cleavable linker) to the glutamine at positions 295 and 297 of cAC10, thereby yielding homogeneous ADCs with a DAR of 4. In vitro cell toxicity experiments using two different CD30-positive cell lines (Karpas 299 and Raji-CD30(+)) revealed comparable EC50 values for ADCETRIS (1.8 +/- 0.4 and 3.6 +/- 0.6 ng/mL, respectively) and the four cAC10-based ADCs (2.0 +/- 0.4 to 4.9 +/- 1.0 ng/mL). Quantitative time-dependent in vivo biodistribution studies (3-96 h p.i.) in normal and xenografted (Karpas 299 cells) SCID mice were performed with a selected I-125-radioiodinated cAC10 ADC and compared with that of I-125-ADCETRIS. The chemo-enzymatically conjugated, radioiodinated ADC showed higher tumor uptake (17.84 +/- 2.2% ID/g 24 h p.i.) than I-125-ADCETRIS (10.5 +/- 1.8% ID/g 24 h p.i.). Moreover, (125)I-ADCETRIS exhibited higher nontargeted liver and spleen uptake. In line with these results, the maximum tolerated dose of the BTG-coupled ADC (>60 mg/kg) was significantly higher than that of ADCETRIS (18 mg/kg) in rats. These results suggest that homogeneous ADCs display improved pharmacokinetics and better therapeutic indexes compared to those of chemically modified ADCs with variable DARs.