S-1 plus oxaliplatin versus capecitabine plus oxaliplatin for first-line treatment of patients with metastatic colorectal cancer: a randomised, non-inferiority phase 3 trial

Lancet Oncol. 2012 Nov;13(11):1125-32. doi: 10.1016/S1470-2045(12)70363-7. Epub 2012 Oct 10.

Abstract

Background: Capecitabine plus oxaliplatin (CapeOX) is one of the reference doublet cytotoxic chemotherapy treatments for patients with metastatic colorectal cancer. We aimed to compare the efficacy and safety of CapeOX with that of S-1 plus oxaliplatin (SOX), a promising alternative treatment for patients with metastatic colorectal cancer.

Methods: In this open-label, multicentre, randomised phase 3 trial, we randomly assigned patients (1:1) from 11 institutions in South Korea to receive either CapeOX (capecitabine 1000 mg/m(2) twice daily on days 1-14 and oxaliplatin 130 mg/m(2) on day 1) or SOX (S-1 40 mg/m(2) twice daily on days 1-14 and oxaliplatin 130 mg/m(2) on day 1). Treatment was repeated every 3 weeks and continued for as many as nine cycles of oxaliplatin-containing chemotherapy, except in instances of disease progression, unacceptable toxicity, or a patient's refusal. Maintenance chemotherapy with S-1 or capecitabine was allowed after discontinuation of oxaliplatin. Randomisation was done with a computer-generated sequence (stratified by primary sites, previous adjuvant or neoadjuvant treatment, and the presence of measurable lesions). The primary endpoint was to show non-inferiority of SOX relative to CapeOX in terms of progression-free survival (PFS). The primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00677443.

Findings: Between May 14, 2008, and Sept 23, 2009, we randomly assigned 168 patients to receive SOX and 172 to receive CapeOX. Median PFS was 8·5 months (95% CI 7·6-9·3) in the SOX group and 6·7 months (6·2-7·1) in the CapeOX group (hazard ratio, 0·79 [95% CI 0·60-1·04]; p(non-inferiority)<0·0001, p(log-rank)=0·09). The upper limit of the CI was below the predefined margin of 1·43, showing the non-inferiority of SOX to CapeOX. We recorded a higher incidence of grade 3-4 neutropenia (49 [29%] vs 24 [15%]), thrombocytopenia (37 [22%] vs 11 [7%]), and diarrhoea (16 [10%] vs seven [4%]) in the SOX group than in the CapeOX group. The frequency of any grade of hand-foot syndrome was greater in the CapeOX group than it was in the SOX group (51 [31%] vs 23 [14%]).

Interpretation: The SOX regimen could be an alternative first-line doublet chemotherapy strategy for patients with metastatic colorectal cancer. Further investigation is needed to explore its potential when used together with other targeted agents or as adjuvant chemotherapy.

Funding: Korea Healthcare Technology Research and Development Project, Ministry of Health and Welfare, South Korea.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antineoplastic Combined Chemotherapy Protocols* / administration & dosage
  • Antineoplastic Combined Chemotherapy Protocols* / adverse effects
  • Capecitabine
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / pathology
  • Colorectal Neoplasms / secondary
  • Deoxycytidine / administration & dosage
  • Deoxycytidine / adverse effects
  • Deoxycytidine / analogs & derivatives*
  • Disease-Free Survival
  • Drug Combinations
  • Female
  • Fluorouracil / administration & dosage
  • Fluorouracil / adverse effects
  • Fluorouracil / analogs & derivatives*
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Organoplatinum Compounds* / administration & dosage
  • Organoplatinum Compounds* / adverse effects
  • Oxaliplatin
  • Oxonic Acid* / administration & dosage
  • Oxonic Acid* / adverse effects
  • Republic of Korea
  • Tegafur* / administration & dosage
  • Tegafur* / adverse effects

Substances

  • Drug Combinations
  • Organoplatinum Compounds
  • Oxaliplatin
  • Deoxycytidine
  • S 1 (combination)
  • Tegafur
  • Oxonic Acid
  • Capecitabine
  • Fluorouracil

Associated data

  • ClinicalTrials.gov/NCT00677443