2014ASCO最新发布：KRAS野生型患者转移性结直肠癌（mCRC）的一线靶向治疗，西妥昔单抗的疗效未能证实优于贝伐珠单抗。

此次ASCO上，大型三期头对头临床研究CALGB80405 的主要结果进行了发布，此研究旨在证实KRAS野生型mCRC患者中， 一线应用西妥昔单抗比一线应用贝伐珠单抗获得更长的生存获益（OS）。

然而，此研究主要研究终点未能达到，即此研究未能证实KRAS野生型mCRC患者一线应用西妥昔单抗比一线应用贝伐珠单抗的生存获益更长。

研究简介

在1137 例可评估患者中，中位OS：西妥昔单抗vs贝伐珠单抗，29.93个月vs 29.04个月，HR=0.92，p=0.34；中位PFS：西妥昔单抗vs贝伐珠单抗，10.4个月vs10.8个月，HR =1.04，p=0.55 。其中73.4%为联合FOLFOX方案，26.6% 联合FOLFIRI方案，FOLFOX亚组OS：FOLFOX+西妥昔单抗vs FOLFOX+贝伐珠单抗，30.1个月vs 26.9个月，HR=0.9，p=0.09；FOLFIRI亚组OS：FOLFIRI+西妥昔单抗vsFOLFIRI+贝伐珠单抗，28.9个月vs 33.4个月，HR=1.2，p=0.26。

CALGB80405是继FIRE3之后又一个主要研究结果为阴性的大型头对头临床研究。在FIRE3 尝试证实KRAS野生型mCRC患者中一线应用西妥昔单抗的ORR显著优于贝伐珠单抗的ORR失败之后，CALGB80405在OS方面期望证实一线应用西妥昔单抗的OS显著优于贝伐珠单抗的OS的尝试再次失败。

2个大型的头对头临床研究提示我们，在KRAS野生型mCRC 患者中，无论是近期疗效，还是远期疗效， 贝伐珠单抗和西妥昔单抗这2种靶向药物作为一线治疗的疗效是一致。

医脉通整理报道，转载请注明出处。

会议专题》》》2014年ASCO年会专题报道

阅读英文原文

The large, phase III CALGB 80405 study, conducted by the Cancer and Leukemia Group B (CALGB), was designed to determine if people without mutations in the KRAS gene (people with KRAS wild-type metastatic colorectal cancer (mCRC)) would live longer when treated with cetuximab (Erbitux) and chemotherapy compared to bevacizumab (Avastin) and chemotherapy. 

The primary endpoint of the study, an improvement in OS of cetuximab (Erbitux) compared to bevacizumab (Avastin), was not reached. 

Cetuximab (Erbitux) failed to show superiority to bevacizumab (Avastin) in people with KRAS wild-type mCRC; both medicines helped people in this study live a similar length of time (median OS of 29.93 months for patients in the cetuximab (Erbitux) treatment arm versus 29.04 months for patients in the bevacizumab (Avastin) treatment arm (HR=0.92, p=0.34)). 

In KRAS wild-type mCRC patients, who are eligible for treatment with anti-EGFR therapy, the specific treatment with cetuximab (Erbitux) was not able to demonstrate superior overall survival compared to bevacizumab (Avastin), an anti-VEGF therapy. 

The secondary endpoints of progression-free survival (PFS) and objective response rate (ORR) were also similar between treatment arms.

Median PFS of 10.45 months in the cetuximab (Erbitux) arm versus 10.84 months in the bevacizumab (Avastin) arm.ORR ~ details TBC                      

The CALGB 80405 study results are clinically important as they address the question about which medicine may be the most appropriate first-line treatment for people with KRAS wild-type mCRC. CALGB 80405 informs physicians that cetuximab (Erbitux) and bevacizumab (Avastin) are similarly effective as a first-line treatment in KRAS wild-type mCRC.