A phase I study of tumor treating fields (TTFields) in combination with pemetrexed for pretreated advanced non-small cell lung cancer

e18500 Background: TTFields (tumor treating fields) are low intensity, intermediate frequency, alternating electric fields which slow the growth of solid tumors in-vivo, and have shown promise in pilot clinical trials in patients with advanced solid tumors. TTFields are a regional treatment which acts both by interfering with microtubules polymerization and by physical disruption of the cell structure during cytokinesis. It has been shown previously that TTFields sensitize non-small cell lung cultures to Pemetrexed. In-Vivo, TTFields did not increase pemetrexed related toxicity. Methods: A prospective trial was performed in 14, pretreated, stage IIIb-IV, NSCLC patients. Patients with brain metastases were excluded, as were patients with abnormal marrow, kidney, liver or cardiac functions. Patients with history of clinically significant arrhythmias or those having pacemakers were excluded as well. Patients received Pemetrexed 500mg/m2 IV q3w together with daily TTFields (12 h/day) using a portable medical device (NovoTTF-100L). The device generated 2 direction (AP and Lat), 150 kHz TTFields. Patients were followed every three weeks and had a lung CT every 9 weeks. The primary endpoint was the safety and tolerability of the NovoTTF-100L device in combination with pemetrexed. Results: The 14 patients received an average of 4 courses of pemetrexed (Range 1–9) and a cumulative TTFields treatment time of 182 weeks. The device was well tolerated as indicated in the device log files which showed an average daily use of 11±1 hours. There were no device-related, nor pemetrexed-related SAEs. In addition, no unexpected abnormalities were evident in the lab tests or EKGs, done every 3 weeks for all patients. There were no reports of arrhythmias. The only device related AE seen in all patients was dermatitis under the electrodes. This improved with meticulous skin care, topical steroid use and in extreme cases oral steroids. One patient (7.6%) had a CR, 1 a PR (7.6%), 9 SD (69.2%) and 3 PD (23%). 77% of patients were progression free at 12 weeks and the 6 month survival was 89%. Conclusions: TTFields are well tolerated when given together with pemetrexed. The excellent safety profile and initial efficacy results reported here justify further clinical testing. [Table: see text]