Background: Compared to placebo, trifluridine/tipiracil (FTD/TPI) significantly improved overall and progression-free survival in patients (pts) with pre-treated metastatic colorectal cancer (mCRC) in the phase III RECOURSE trial. Although time to deterioration of ECOG performance status (PS) from 0/1 to ≥ 2 was significantly longer in pts treated with FTD/TPI, health-related quality of life (HRQoL) was not formally assessed by direct means. Therefore, a two-arm trial with best supportive care (BSC) as appropriate comparative treatment was designed to specifically address the effect of FTD/TPI on HRQoL. Methods: In this prospective, multi-center, German, open-label, phase IV study, pts with pre-treated mCRC could choose between BSC or oral FTD/TPI (35 mg/m²bid on days 1-5 and 8-12 of each 28-day cycle). EORTC QLQ-C30 and EQ-5D-5L questionnaires were employed to assess HRQoL. Primary endpoint was the rate of responders with stabilized ( > -10 and < 10 scores) or improved (≥ 10 scores) response (RR). Response was calculated as the mean score of the EORTC QLQ-C30 global health status/ QoL scale from the 2^nd cycle until the end of treatment/ observation compared to the baseline score. Results: Of 194 eligible pts, 185 pts chose treatment with FTD/TPI (median 3 cycles), while 9 pts decided to receive BSC only. Questionnaires from 109 pts receiving FTD/TPI and from 6 pts with BSC were evaluable for RR. The primary endpoint (RR) was 59.6% (95% CI 49.8 – 68.9) in FTD/TPI-treated pts and 50.0% (95% CI 11.8 – 88.2) in pts receiving BSC. Analysis of the extended follow-up period, demonstrated that RR was 67.0% (95% CI 57.3 – 75.7) in FTD/TPI-treated pts. In the FTD/TPI-group, median time to deterioration of HRQoL was 121 days (n = 61; 95% CI 87 – 151) according to EORTC QLQ-C30 and 119 days (n = 63; 95% CI 85 – 138) according to EQ-5D-5L. Conclusions: If pts can choose between treatment and BSC in late-stage CRC, the vast majority opts for treatment. According to the present results, FTD/TPI-treatment induced prolonged stabilization of HRQoL, a highly desired attribute of therapies for pts with late-stage cancer. Clinical trial information: No 2017-000292-83.