Final results from a Phase II study of pemetrexed and cisplatin with concurrent thoracic radiation after Pem-Cis induction in patients with unresectable locally advanced non-squamous non-small cell lung cancer (NSCLC)

AbstractObjectivesThis single-arm multicenter Phase II study investigated the efficacy and safety of pemetrexed (Pem) and cisplatin (Cis) induction chemotherapy (CT) followed by full-dose Pem-Cis plus concurrent radiotherapy (RT) in patients with locally advanced non-squamous NSCLC.Materials and methodsPatients with unresectable Stage III non-squamous NSCLC received two 21-day cycles of Pem 500mg/m2 (vitamin/folic acid supplementation and dexamethasone prophylaxis per Pem-label)+Cis 75mg/m2 on Day 1. Eligible patients who had not progressed continued with 2 further cycles of full-dose Pem-Cis plus concurrent RT (2Gy/fraction, 5 days/week, 66Gy total). Primary endpoint was the 1-year progression-free survival (PFS) rate.ResultsOf 90 patients enrolled (all treated; median age 61 years, male/female 57%/43%, ECOG performance status 0/1 66%/34%, adenocarcinoma 90%, Stage III 36%/62%), 75 (83%) completed induction CT and started concurrent CT+RT. 64 (71%) patients received all 4 CT cycles and an RT dose ≥60Gy. The 1-year PFS rate was 51.3% (95%CI: 42.0, 60.5). Median PFS was 10.6 months (95%CI: 8.6, 17.3), median OS was 26.2 months (95%CI: 16.7, not estimable). One patient died from enteritis (treatment-related) during Cycle 4. Four patients discontinued due to treatment-related adverse events, 1 on induction CT (renal failure), 3 on concurrent CT+RT (1 hypoacusis, 2 acute esophagitis). During induction CT, 18.9% of patients reported Grade 3/4 CTCAEs, only neutropenia (2.2%) and syncope (2.2%) were reported by >1 patient. During concurrent CT+RT, 41.3% of patients reported G3/4 CTCAEs, mainly esophagitis (12.0%), neutropenia (10.7%), and leukopenia (9.3%).ConclusionIn this study of Pem-Cis induction CT followed by full-dose Pem-Cis with concurrent RT, median PFS was 10.6 months and toxicity was manageable, in line with previous data on Pem-Cis plus RT