Patient-reported outcomes from a phase III multicenter, randomized, double-blind, placebo-controlled trial of gefitinib versus placebo in esophageal cancer progressing after chemotherapy: Cancer Oesophagus Gefitinib (COG).

Abstract

6 Background: There are no randomised trials of 2nd line chemotherapy for esophageal cancer. The phase III COG trial of gefitinib versus placebo in patients with esophageal cancer progressing after chemotherapy did not show significant overall survival (OS) benefit, however the trial incorporated patient reported outcomes (PRO) using validated tools. The PRO data are therefore critical to inform practice and the initial results are presented here. Methods: Adults with measurable/evaluable metastatic esophageal or types I/II junctional adeno or squamous cell carcinoma progressing after prior chemotherapy, with performance status 0-2 were randomised 1:1 to 500mg gefitinib (G) or placebo (P), treated until progression. Primary outcome: OS. Secondary outcomes include safety, PFS, PRO (assessed by EORTC QLQ-C30 and EORTC QLQ-OG25 at baseline 4, 8 and 12 weeks until progression) and predictive biomarkers. Pre-specified PRO domains were global quality of life, dysphagia, eating and odynophagia. Analysis by ANCOVA of change in PRO at 4 weeks adjusted for baseline. Results: 450 patients were recruited from 51 UK centres and no difference in OS was detected. There was evidence that PFS was better in the intervention arm (P 35 days, G 49 days; HR=0.795, 95%CI 0.66, 0.96, p=0.017). Questionnaire compliance rates were excellent at baseline (94%) and at 4 weeks (77%). Patients in the gefitinib arm reported significantly better social function (9.26; 95%CI 1.94 to 16.58; p=0.013) and significantly fewer problems with odynophagia (-8.61; 95%CI -14.49 to -2.73; p=0.004), constipation (-15.24; 95%CI -22.83 to -7.65; p=0.0001) and speech (-10.40; 95%CI -16.13 to -4.67; p=0.0004) than patients receiving placebo but more problems with diarrhoea (19.23; 95%CI 11.79 to 26.27; p<0.0001). All other PRO domains were similar between the two groups. Conclusions: Gefitinib did not improve overall survival in esophageal cancer patients after chemotherapy however there was significant PFS improvement and improvement in quality of life and palliation of symptoms albeit with an excess of diarrhoea. Clinical trial information: 29580179.