A Phase II Randomized Study of Cisplatin-Pemetrexed plus either Enzastaurin or Placebo in Chemonaive Patients with Advanced Non-Small Cell Lung Cancer

Objectives: Enzastaurin is a serine/threonine kinase inhibitor that targets protein kinase C and AKT pathways. Enzastaurin and pemetrexed demonstrated synergy in preclinical studies. This trial was designed to evaluate the safety and efficacy of first-line enzastaurin plus cisplatin-pemetrexed in advanced non-small cell lung cancer (NSCLC). Methods: A safety lead-in phase (n = 13) of enzastaurin 125 or 250 mg twice daily was added to cisplatin-pemetrexed. A subsequent randomized, placebo-controlled phase II study (n = 22) of the combination was conducted to evaluate efficacy. Results: The combination was well tolerated and showed activity, with 7 (53.8%, 95% CI 26.7–80.9) confirmed partial responses and 2 stable diseases in 13 treated patients in the lead-in phase. However, the study was terminated early based on interim results from two phase II NSCLC studies of enzastaurin plus cytotoxic chemotherapy, which indicated no efficacy improvement. Conclusions: Enzastaurin and cisplatin-pemetrexed is tolerable with preliminary activity in patients with advanced NSCLC, but because of a lack of efficacy improvement in other phase II NSCLC studies, the study was terminated early.