Reduced-dose combination chemotherapy (S-1 plus oxaliplatin) versus full- dose monotherapy (S-1) in older vulnerable patients with metastatic colorectal cancer (NORDIC9) : a randomised, open-label phase 2 trial

• Background: Older or vulnerable patients with metastatic colorectal cancer are seldom included in randomised trials.The multicentre NORDIC9 trial evaluated reduced-dose combination chemotherapy compared with full-dose monotherapy in older, vulnerable patients.Methods: This randomised, open-label phase 2 trial was done in 23 Nordic oncology clinics and included patients aged 70 years or older with previously untreated metastatic colorectal cancer who were not candidates for full-dose combination chemotherapy. Patients were block randomised (1: 1) using a web-based tool to full-dose S-1 (30 mg/m(2) orally twice daily on days 1-14 every 3 weeks) followed by second-line treatment at progression with irinotecan (250 mg/m(2) intravenously on day 1 every 3 weeks or 180 mg/m(2) intravenously on day 1 every 2 weeks) or reduceddose combination chemotherapy with S-1 (20 mg/m(2) orally twice daily on days 1-14) and oxaliplatin (100 mg/m(2) intravenously on day 1 every 3 weeks) followed by second-line treatment at progression with S-1 (20 mg/m(2) orally twice daily on days 1-14) and irinotecan (180 mg/m(2) intravenously on day 1 every 3 weeks). Use of bevacizumab (7.5 mg/kg intravenously on day 1 of each cycle) was optional. Treatment allocation was not masked and randomisation was stratified for institution and bevacizumab. The primary outcome was progression-free survival. Survival analyses were by intention to treat and safety analyses were done on the treated population. This trial is registered with EudraCT, number 2014-000394-39, and is closed to new participants.Findings: From March 9, 2015, to Oct 11, 2017, 160 patients with a median age of 78 years (IQR 76-81) were randomly assigned to full-dose monotherapy (n=83) or reduced-dose combination chemotherapy (n=77). At data cutoff (Sept 1, 2018; median follow-up 23.8 months [IQR 18.8-30.9]), 81 (98%) patients in the full-dose monotherapy group and 71 (92%) patients in the reduced-dose combination group had progressed or died. Median progression-free survival was significantly longer with reduced-dose combination chemotherapy (6.2 months [95% CI 5.3-8.3]) than with full-dose monotherapy (5.3 months [4.1-6.8]; hazard ratio [HR] 0.72 [95% CI 0.52-0.99]; p=0.047). Toxicity was evaluated in 157 patients who received treatment. Significantly more patients in the full-dose monotherapy group (51 [62%] of 82 patients) experienced at least one grade 3-4 adverse event than in the reduced-dose combination group (32 [43%] of 75 patients; p=0.014). Grade 3-4 diarrhoea (12 [15%] vs two [3%]; p=0.018), fatigue (ten [12%] vs three [4%]; p=0.083), and dehydration (five [6%] vs none; p=0.060) were more frequent in the full-dose monotherapy group than in the reduced-dose combination group. Treatment-related deaths occurred in three patients during firstline treatment and three patients during second-line treatment (two in the full-dose monotherapy group vs one in the reduced-dose combination group in both cases).Interpretation: Reduced-dose combination chemotherapy with S-1 and oxaliplatin for older, vulnerable patients with metastatic colorectal cancer was more effective and resulted in less toxicity than full-dose monotherapy with S-1. Reduced-dose combination chemotherapy could be a preferred treatment for this population.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Cancer och onkologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cancer and Oncology (hsv//eng)

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)