704P - Final Safety Analysis of Erlotinib Plus Gemcitabine in a Post-Marketing Surveillance Study (Polaris) of >800 Japanese Pancreatic Cancer Patients

Abstract

ABSTRACT Aim: Erlotinib is approved in Japan for the treatment of unresectable pancreatic cancer (PC) in combination with gemcitabine (GE). This surveillance study investigated the safety and efficacy of GE in Japanese patients (pts), focusing on the incidence of interstitial lung disease (ILD), an adverse drug reaction (ADR) of particular concern in these pts. Methods: All pts receiving GE for treatment of PC in Japan between Jul 2011 and Aug 2012 were enrolled; pts with current/former ILD were excluded. Observation period: 28 wks. ADRs: adverse events where GE could not be ruled out as the cause. All ILD-like events were assessed by an independent ILD review committee (IRC). ILD: all ILD-like events excluding those deemed non-ILD by the IRC. Risk factors for ILD occurrence were analysed by multivariate Cox regression analysis. Both PFS and OS were assessed by the investigator. Results: A total of 848 pts had case report forms by the data cut-off of Dec 2013 (safety data were available for 843 pts). Baseline characteristics included: male 58.1%; median age 65 yrs; any smoking history 44.1%; lung metastases 14.0%; ECOG PS 0 69.2%; prior treatment lines 0/1/2/ ≥ 3: 80.5%/11.3%/5.1%/3.1%. ADRs were reported in 83.5% of pts; the most common were skin disorders (69.9%), including rash (63.6%), and diarrhoea (17.6%). Most ADRs were grade ≤2. ILD events were confirmed by IRC in 52 pts (6.2%), of whom 2 pts had grade 5 ILD (0.2%). This is in contrast to the higher ILD mortality rate (1.5%) previously seen in NSCLC pts. The multivariate analysis identified age ≥75 yrs and existence of any lung disease as a potential risk factor for whether pts developed ILD. Median PFS was 104 days (95% CI 92–112) and accumulated OS rate at 8, 16 and 28 wks was 95.3%, 85.0% and 68.2%, respectively. Conclusions: The safety profile from this large surveillance study was similar to previous clinical studies of GE in PC. These final data from this study in Japanese PC pts provide further information, especially on risk factors for ILD occurrence, which will be reported in more detail. Improved awareness of these risk factors will help clinicians guide GE treatment in these pts. Note: Authors Furuse, Gemma, Hatori, Okusaka attended an Independent Advisory Board for Erlotinib. Disclosure: J. Furuse: I have served on an independent erlotinib advisory board for Chugai Pharmaceutical Co., Ltd.; A. Gemma: I have served on an independent erlotinib advisory board for Chugai Pharmaceutical Co., Ltd.; T. Hatori: I have served on an advisory board for Chugai Pharmaceutical Co., Ltd.; T. Okusaka: I have served on an advisory board for Chugai Pharmaceutical Co., Ltd.; A. Seki: I am an employee of Chugai Pharmaceutical Co., Ltd. and have some stock ownership at Kissei Pharmaceutical Co., Ltd.