CDK4/6抑制剂（下）

 激素受体阳性型（HR+）乳腺癌是指雌激素受体（ER）和或孕激素受体（PR）表达阳性的患者，约占所有乳腺癌类型的75%。对于HR+患者，内分泌治疗为其标准的治疗方案，常见的内分泌治疗药物包括三苯氧胺、氟维司群以及芳香化酶抑制剂来曲唑、阿那曲唑、依西美坦等。但是由于原发性或者继发性耐药的出现，使患者的获益极大地降低，也迫使着探讨其耐药的机制。引起内分泌药物耐药的机制有很多，近年来研究发现与cyclin D1-CDK4/6信号通路的异常激活有关。前期的体外细胞实验发现，CDK4/6特异性抑制剂对HR+阳性型乳腺癌细胞株最敏感，与三苯氧胺联用时具有协同作用，并能在细胞株水平逆转三苯氧胺的耐药。同期I期临床试验结果也发现，CDK4/6抑制剂对HR+患者具有很好的疗效，获得更长的PFS时间。这些前期试验结果提示进一步探讨CDK4/6抑制剂与内分泌药物联合使用的可能。 

1. 基本信息

2. 临床研究进展

2.1 晚期一线临床研究

2.2 既往内分泌治疗进展/后线治疗

参考文献：

[1] Clinicaltrials.gov. NCT02246621. 

[2] Clinicaltrials.gov. NCT01958021. 

[3] Clinicaltrials.gov. NCT02278120. 

[4] Clinicaltrials.gov. NCT02107703. 

[5] Clinicaltrials.gov. NCT02422615. 

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