Efficacy and Toxicity of Maintenance Pemetrexed Following Induction Treatment with Pemetrexed Plus Cisplatin for Advanced Non-small-cell Non-squamous Carcinoma of the Lung

INTRODUCTION: The aim of this study is to assess the efficacy and toxicity of maintenance pemetrexed following induction treatment with cisplatin and pemetrexed for patients with advanced non-small cell lung cancer.

PATIENTS AND METHODS: Eligible patients following four cycles of intravenous pemetrexed (Alimpta©; 500 mg/m²) and intravenous cisplatin (75 mg/m²) were given 21-day cycles of maintenance pemetrexed (500 mg/m²) until disease progression, unacceptable adverse event or death. From a total 80 patients receiving palliative induction chemotherapy, 17 subsequently received maintenance pemetrexed.

RESULTS: The mean number of maintenance cycles completed was 5.9 (range 1-20; median 3.0). The mean progression-free survival (PFS) was 5.2 months (range: 2-15; median: 2.0) and the 1-year PFS was 17%. Treatment was discontinued due to disease progression (71%), adverse event (21%) and death from study disease (7%). Grade 3-4 laboratory and non-laboratory adverse events were seen in 11.8 and 17.6% of patients, respectively. Anaemia was the most common adverse event (71% of all patients; 65% grade 1-2; 5.9% grade 3-4). The most common reason for withdrawal due to adverse event was declining renal function. There was a statistically significant correlation between worsening performance status and reducing number of maintenance cycles completed (Spearman’s rank; R = −0.511, p = 0.036).

DISCUSSION: The median PFS was lower than in previous studies with a higher than previously reported frequency of adverse events. Clinicians must monitor renal function and full blood counts vigilantly, especially in patients with performance status greater than 0.