1214 - A Phase II Clinical Trial of Tumor Treating Field (TTF) Therapy Concomitant to Pemetrexed for Advanced Non-Small Cell (NSCLC) Lung Cancer

Abstract

ABSTRACT Background TTF therapy is a novel, non-invasive treatment modality for solid tumors recently approved by FDA for recurrent GBM. It uses intermediate frequency alternating electric fields to inhibit tumor growth, by mitotic spindle and plasma membrane integrity disruption during cytokinesis. Pemetrexed is a folate antimetabolite used as a first/second line and as a maintenance therapy for non-squamous NSCLC patients. Preclinical studies in NSCLC models demonstrated that TTF therapy and pemetrexed had additive efficacy, with no increase in toxicity. The current trial tested TTF therapy concomitant to pemetrexed in NSCLC patients. Methods A single arm, multi-center, prospective trial was performed in 42 stage IIIB (with pleural effusion) and IV NSCLC patients, following progression after at least one prior chemotherapy. Patients received continuous 150 KHz TTF therapy (12 h/day) using the NovoTTF-100L system (NovoCure, Israel), concomitant to pemetrexed (Alimta™, Eli Lilly) q3w, until progression. Pemetrexed was in use for squamous histology when the study opened. Results The trial included 35 patients with non-squamous histology and 7 patients with squamous histology. TTF Therapy was well tolerated by all patients enrolled in the trial, with high compliance (11 h/day). No TTF-related adverse events were reported apart from dermatitis caused by the application of transducer arrays. Median progression free survival was 22.7 and 10.3 weeks for non-squamous and squamous histology, respectively. Seven patients who initially had in-field-only disease (including squamous histology) had distant metastases before progressing in-field. Median overall survival was 12.4 and 13.8 months for nonsquamous and squamous histology, respectively. One- and two- year-survival was 53% and 27%, respectively. Conclusions TTF therapy concomitant to pemetrexed was well tolerated and safe for patients with advanced NSCLC, of all histologies. Efficacy indices are promising, in view of the poor outcome previously reported for similar populations. This first clinical trial involving TTF as a treatment for NSCLC patients suggests that it should be further studied in larger clinical trials for squamous and nonsquamous NSCLC Disclosure M. Salzberg: Medpace Inc. is a contracted Contract Research Organization (CRO) for Novocure Ltd. All other authors have declared no conflicts of interest.