Dose escalation to rash for erlotinib plus gemcitabine for metastatic pancreatic cancer: The phase II RACHEL study

Background: This phase II, open-label, randomised study evaluated whether patients with metastatic pancreatic cancer receiving erlotinib/gemcitabine derived survival benefits from increasing the erlotinib dose. Methods: After a 4-week run-in period (gemcitabine 1000 mg m-2 once weekly plus erlotinib 100 mg per day), patients with metastatic pancreatic cancer who developed grade 0/1 rash were randomised to receive gemcitabine plus erlotinib dose escalation (150 mg, increasing by 50 mg every 2 weeks (maximum 250 mg); n=71) or gemcitabine plus standard-dose erlotinib (100 mg per day; n=75). The primary end point was to determine whether overall survival (OS) was improved by increasing the erlotinib dose. Secondary end points included progression-free survival (PFS), incidence of grade ≥2 rash, and safety.Results:Erlotinib dose escalation induced grade ≥2 rash in 29 out of 71 (41.4%) patients compared with 7 out of 75 (9.3%) patients on standard dose. Efficacy was not significantly different in the dose-escalation arm compared with the standard-dose arm (OS: median 7.0 vs 8.4 months, respectively, hazard ratio (HR), 1.26, 95% confidence interval (CI): 0.88-1.80; P=0.2026; PFS: median 3.5 vs 4.5 months, respectively, HR, 1.09, 95% CI: 0.77-1.54; P=0.6298). Incidence of adverse events was comparable between randomised arms.Conclusion:The erlotinib dose-escalation strategy induced rash in some patients; there was no evidence that the higher dose translated into increased benefit.