Phase III study of enzastaurin compared with lomustine in the treatment of recurrent intracranial glioblastoma

PURPOSE

This phase III open-label study compared the efficacy and safety of enzastaurin versus lomustine in patients with recurrent glioblastoma (WHO grade 4).

PATIENTS AND METHODS

Patients were randomly assigned 2:1 to receive 6-week cycles of enzastaurin 500 mg/d (1,125-mg loading dose, day 1) or lomustine (100 to 130 mg/m(2), day 1). Assuming a 45% improvement in progression-free survival (PFS), 397 patients were required to provide 80% power to achieve statistical significance at a one-sided level of .025.

RESULTS

Enrollment was terminated at 266 patients (enzastaurin, n = 174; lomustine, n = 92) after a planned interim analysis for futility. Patient characteristics were balanced between arms. Median PFS (1.5 v 1.6 months; hazard ratio [HR] = 1.28; 95% CI, 0.97 to 1.70), overall survival (6.6 v 7.1 months; HR = 1.20; 95% CI, 0.88 to 1.65), and 6-month PFS rate (P = .13) did not differ significantly between enzastaurin and lomustine, respectively. Stable disease occurred in 38.5% and 35.9% of patients and objective response occurred in 2.9% and 4.3% of patients, respectively. Time to deterioration of physical and functional well-being and symptoms did not differ between arms (HR = 1.12; P = .54). Four patients discontinued enzastaurin because of drug-related serious adverse events (AEs). Eleven patients treated with enzastaurin died on study (four because of AEs; one was drug-related). All four deaths that occurred in patients receiving lomustine were disease-related. Grade 3 to 4 hematologic toxicities were significantly higher with lomustine (46 events) than with enzastaurin (one event; P < or = .001).

CONCLUSION

Enzastaurin was well tolerated and had a better hematologic toxicity profile but did not have superior efficacy compared with lomustine in patients with recurrent glioblastoma.

Molecular profiling in glioblastoma: prelude to personalized treatment

The purpose of this review is to provide an up-to-date summary of the current knowledge and understanding of the molecular alterations and pathways relevant to the clinical outcome of glioblastoma patients and their potential use in designing personalized treatment for these patients. This article also discusses the potential of molecular profiling as a diagnostic modality, possible therapeutic implications of MGMT promoter methylation, the targeted inhibition of angiogenesis, and assessment of the tumor's molecular background with respect to PI3K/AKT pathway activation and associated molecules (EGFR, EGFRvIII, PTEN).