452P - Pemetrexed versus best supportive care following platinum-based doublet chemotherapy for patients with advanced nonsmall cell nonsquamous lung cancer

Abstract

Background: From very beginning optimal treatment strategy for advanced disease ca lung (Stage IIIB or IV) was, four to six cycles platinum based combined (doublet) regimen then observation and subsequently administration of second line chemotherapy with the progression of disease. Maintenance therapy in ca lung is a latest growing idea, improving quality of life. The advantage of using switch maintenance therapy over continuation therapy that a valuable number of tumor cells responds to different active agent when resistant to the first-line treatment. On the basis of this, we conducted a reterospectivev study compare pemetrexed versus best supportive care (BSC) as switch maintenance therapy. Methods: Between July 2012 and January 2014, newly diagnosed patients with Stage IIIB/IV NSCLC (nonsquamous) received six cycles of carboplatin AUC 6 or 7 (day1) and paclitaxel (175 mg/m2 day 1) every 3 weeks, nonprogressores and patients with stable disease were randomized 1:1 to receive maintenance pemetrexed 500 mg/m2 IV infusion over 10 minutes on day 1 of each 21-day cycle or BSC alone untill progression of disease. Vitamin B12, Folic acid and dexamethasone added to pemetrexed according to standard protocol. The primary endpoint was a comparison of overall survival (OS) between pemetrexed and BSC group, and the secondary endpoint was progression-free survival (PFS). Results: Initially total of 128 patients were enrolled in this study. Patients characteristics were as follows (stage IV disease 54%, ECOG performance status 0-1: 71.2s%, median age 54 years, male 81%,). These all patients received 6 cycles of initial therap. Further 71.09% (91 patients) nonprogessors randomly distributed for Pemetrexed (n = 46) and BSC group (n = 45). The median OS for Pemetrexed group was 13.2 months and 10.6 months for BSC, with a hazard ratio (HR) 0.77 (95% CI: 0.61–0.93, P = 0.003). The median PFS was 6.4 months for pemetrexed versus 4.8 months for BSC, with a HR 0.66 (95% CI: 0.48–0.84, P = 0.007). Hematological toxicities were the main toxicities specially grade 3/4 neutropenia and anemia Conclusions: Switch maintenance therapy with Pemetrexed, after doublet chemotherapy specially platinum based in advanced nonsquamous NSCLC has produced appreciable longer OS and PFS compared to BSC alone at the cost of higher grade 3/4 hematological toxicities. Legal entity responsible for the study: sp medical college radiotherapy department bikaner rajasthan Funding: None Disclosure: All authors have declared no conflicts of interest.