Postmarketing surveillance study of erlotinib plus gemcitabine for pancreatic cancer in Japan: POLARIS final analysis.

objectiveErlotinib plus gemcitabine is approved in Japan for the treatment of metastatic pancreatic cancer. The POLARIS surveillance study investigated safety (focusing on interstitial lung disease [ILD]) and efficacy of erlotinib plus gemcitabine in Japanese pancreatic cancer patients.

methodsPatients receiving erlotinib plus gemcitabine for pancreatic cancer in Japan between July 2011 and August 2012 were enrolled. ILD-like events were independently confirmed by a review committee. Overall survival (OS) and progression-free survival (PFS) were assessed, and risk factors for ILD occurrence were analyzed by multivariate Cox regression analysis.

resultsSafety data were available for 843 patients and efficacy data for 841. Adverse drug reactions were reported in 83.5% of patients, no new safety signals were identified. ILD events were confirmed by the review committee in 52 patients (6.2%), with two fatal cases (0.2%). Median time from initial erlotinib treatment to ILD events was 70.5 days. Of the 52 patients with ILD events, 86.5% improved or fully recovered from ILD (median time 24 days). Multivariate analysis identified previous or concurrent lung disease (hazard ratio [HR], 2.2; 95% confidence interval [CI], 1.0-4.5; P = 0.0365) and ≥3 organs with metastases (HR, 4.2; 95% CI, 2.2-8.2; P < 0.0001) as potential ILD risk factors. Accumulated OS rate at 28 weeks was 68.2%, and median PFS was 92 days (95% CI, 86-101).

conclusionsErlotinib plus gemcitabine has an acceptable safety and efficacy profile in pancreatic cancer; however, patients should be assessed for previous/concurrent lung disease and metastatic burden, before and during treatment.