445P - Real-world evidence (RWE) on the clinical outcomes in 1st-line chemotherapy (CT) for fit and vulnerable patients (pts) with metastatic colorectal cancer (mCRC)

Background

In mCRC, the doublet or triplet CT with or without molecular targeted agent (MTA) has been widely accepted as the 1^st-line treatment for pts with good medical condition (“fit pts”). While, less intensive treatment is applied for pts due to their medical condition (“vulnerable pts”). However, the RWE on clinical outcomes in fit and vulnerable pts has been limited.

Methods

This retrospective study assessed 1^st-line CT in mCRC included in Medical Data Vision Co., Ltd. (Tokyo, Japan) Database from 393 Japanese hospitals between 2008 and 2019. We defined doublet, fluoropyrimidines (FPs) plus oxaliplatin (OX) or irinotecan (IRI), or triplet, FPs plus OX and IRI, with or without MTA as the regimens for fit pts (Fit regimen) and FPs with or without bevacizumab (BEV) or anti-EGFR antibody mono therapy as the regimens for vulnerable pts (Vulnerable regimen). Key endpoints are time-to-treatment failure (TTF), time-to-first subsequent therapy (TFST), and overall survival (OS).

Results

A total 3,874 pts (86%) and 633 pts (14%) received the Fit and Vulnerable regimen respectively. In the Vulnerable regimen, the median age was significantly higher (75 vs. 67, p<0.001) and the activities of daily living (ADL) was significantly worse (p<0.001) than those in the Fit regimen. The median TTF, TFST and OS were 4.4 months (mo.), 7.2 mo. and 22.1 mo. in the Fit regimen, and 1.4 mo., 4.9 mo. and 12.2 mo. in the Vulnerable regimen, respectively. Among pts treated with doublet CT (N=3,712), all efficacy outcomes were significantly better in the pts received MTA (hazard ratio [HR] in TTF, 0.49; HR in TFST, 0.60; HR in OS, 0.68), and there was no significant difference between BEV and anti-EGFR antibody (HR in TTF, 0.98; HR in TFST, 1.02; HR in OS, 1.12). While, in the Vulnerable regimen, adding BEV to FPs (131 pts in FPs plus BEV vs. 433 pts in FPs) significantly prolonged TTF (HR, 0.70) but did not TFST and OS (HR in TFST, 0.93; HR in OS, 0.76).

Conclusions

The real-world data revealed that the age and ADL of the pts were the important factors in selecting the Fit or Vulnerable regimen, and MTA improved the efficacy outcomes of doublet chemotherapy in Fit regimen regardless of the type of MTA.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The 22nd Century Cutting-Edge Medical IT Organization.

Funding

Chugai Pharmaceutical Co., Ltd.

Disclosure

K. Yamazaki: Honoraria (self): Chugai Pharma; Honoraria (self): Daiichi Sankyo; Honoraria (self): Yakult Honsha; Honoraria (self): Takeda; Honoraria (self): Bayer; Honoraria (self): Merck Serono; Honoraria (self), Research grant/Funding (institution): Taiho Pharmaceutical; Honoraria (self): Lilly; Honoraria (self): Sanofi; Honoraria (self): Ono Pharmaceutical; Honoraria (self): MSD; Honoraria (self): Bristol-Myers Squibb. T. Yamanaka: Honoraria (self), Research grant/Funding (self): Chugai Pharma. T. Hamano: Full/Part time employment: P4 Statistics Co. Ltd.; Honoraria (self): Chugai Pharma.