P0091 A pilot study of low-dose capecitabine plus trastuzumab as first-line treatment in patients aged 75 years or older with HER2-positive advanced gastric cancer

Abstract

Background Single agent chemotherapy is considered to be an effective and safe treatment option for patients aged 75 years or older with advanced gastric cancer (AGC). We investigated the efficacy and safety of trastuzumab combined with low-dose capecitabine in older patients with previously untreated HER2-positive AGC. Methods Patients aged 75 years or older were eligible for inclusion if their tumours had HER2 overexpression defined as either immunohistochemistry (IHC) 3+ or IHC 2+ and positive in situ hybridisation. 1000 mg/m2 capecitabine was given orally, twice a day for 14 days followed by 1 week with no treatment (rest). Trastuzumab was administered intravenously at a dose of 8 mg/kg on day 1 of the first cycle, and increased to 6 mg/kg every 3 weeks. Findings Between April 2012, and October, 2014 20 consecutive patients were enrolled. The median age of participants was 79 years (range 75–92). Nine (45%) patients had Eastern Cooperative Oncology Group performance status of 2. After the median follow up of 16.0 months (95% CI 0.4–31.6), 14 patients had disease progression and 13 patients died. Median progression-free survival was 5.2 months (95% CI 1.9–8.4) and median overall survival was 9.3 months (95% CI 4.0–14.6). The confirmed objective response rate was 40% (95% CI 19–64). Disease control was achieved in 80% of patients. Grade 3 or 4 toxicities noted were anorexia nervosa (10%), fatigue (5%), stomatitis (5%), and anaemia (5%). No treatment-related deaths or symptomatic congestive heart failure were observed. Interpretation Our study indicates that low-dose capecitabine plus trastuzumab is effective and well tolerated in elderly patients with HER2-positive AGC who are considered to not be eligible for cytotoxic combination chemotherapy. Our results need to be confirmed in additional large studies.