Eribulin mesylate for the treatment of patients with refractory metastatic breast cancer: use of a "physician's choice" control arm in a randomized approval trial.

This work describes the considerations that led to the approval by the U.S. Food and Drug Administration (FDA), on November 15, 2010, of eribulin mesylate (Halaven; Eisai, Inc.) for the treatment of patients with refractory metastatic breast cancer. The FDA review focused primarily on the results of a single randomized, open-label, multicenter trial of 762 patients with refractory locally advanced or metastatic breast cancer. The patients were randomized to receive eribulin or any single-agent treatment of the physician's choice, selected prior to randomization. The FDA's approval of eribulin mesylate was based on demonstration of a statistically significant prolongation of overall survival (OS) in patients who had been randomized to receive eribulin. The median OS was 13.1 months in the eribulin arm compared with 10.6 months in the control arm [HR 0.81 (95% CI, 0.66-0.99); P = 0.041]. Treatment with eribulin did not show a statistically significant treatment effect [HR 0.87 (95% CI, 0.71-1.05)] on progression-free survival as determined by independent review. This approval highlights the appropriate use of an innovative trial design and shows that improvement in OS is an achievable endpoint in the setting of advanced breast cancer. On the basis of the different conclusions arising from the OS and progression-free survival results, investigators should consider using OS as a primary endpoint in clinical trials for refractory breast cancer.

U.S. Food and drug administration approval: rituximab in combination with fludarabine and cyclophosphamide for the treatment of patients with chronic lymphocytic leukemia.

PURPOSE: To describe the clinical studies that led to the FDA approval of rituximab in combination with fludarabine and cyclophosphamide (FC) for the treatment of patients with chronic lymphocytic leukemia (CLL). MATERIALS AND METHODS: The results of two multinational, randomized trials in CLL patients comparing rituximab combined with fludarabine and cyclophosphamide versus FC were reviewed. The primary endpoint of both studies was progression-free survival (PFS). RESULTS: The addition of rituximab to FC decreased the risk of a PFS event by 44% in 817 previously untreated patients and by 24% in 552 previously treated patients. Median survival times could not be estimated. Exploratory analysis in patients older than 70 suggested that there was no benefit to patients when rituximab was added to FC. The safety profile observed in both trials was consistent with the known toxicity profile of rituximab, FC, or CLL. CONCLUSIONS: On the basis of the demonstration of clinically meaningful prolongation of PFS, the FDA granted regular approval to rituximab in combination with FC for the treatment of patients with CLL. The magnitude of the treatment effect in patients 70 years and older is uncertain.