The Futility of Futility Analyses in Adjuvant Trials in Hormone Receptor Positive Breast Cancer

An interim analysis is commonly used in phase III superiority trials to compare treatment arms, with the goal of terminating exposure of patients to ineffective or unsafe drugs, or to identify highly effective therapies for earlier public disclosure. Traditionally, interim analyses have been designed to identify early evidence of extremely large benefit of the experimental approach, potentially leading to early dissemination of effective treatments. Increasingly, interim analysis has also involved analysis of futility which may lead to early termination of a trial that will not yield additional useful information This presents an important challenge in early-stage hormone receptor positive breast cancer, where recurrence often occurs late, with a steady annual event rate up to 20 years. Early analysis of events may miss late treatment effects that can be observed only with longer follow-up. We discuss approaches to futility analysis in adjuvant clinical trials in hormone receptor positive breast cancer, the role of the Data Safety Monitoring Committee in such analyses, considerations of the potential harms versus benefits of treatment, and the risks of continuing versus early stopping of a trial.

A phase I study using bortezomib with weekly idarubicin for treatment of elderly patients with acute myeloid leukemia

We report the results of a phase I study with four dose levels of bortezomib in combination with idarubicin. Eligible patients were newly diagnosed with acute myeloid leukemia (AML) age ≥60 years, or any adult with relapsed AML. Bortezomib was given twice weekly at 0.8, 1.0, or 1.2 mg/m(2) with once weekly idarubicin 10 mg/m(2) for four weeks. Twenty patients were treated: 13 newly diagnosed (median age 68, range 61-83) and 7 relapsed (median age 58, range 40-77). Prior myelodysplastic syndrome (MDS) was documented in 10/13 (77%) newly diagnosed and 1/7 (14%) relapsed patients; the three newly diagnosed patients without prior MDS had dyspoietic morphology. Two dose-limiting toxicities occurred at the initial dose level (bortezomib 0.8 mg/m(2) and idarubicin 10 mg/m(2)); idarubicin was reduced to 8 mg/m(2) without observing subsequent dose-limiting toxicities. The maximum tolerated dose in this study was bortezomib 1.2 mg/m(2) and idarubicin 8 mg/m(2). Common adverse events included: neutropenic fever, infections, constitutional symptoms, and gastrointestinal symptoms. No subjects experienced neurotoxicity. Most patients demonstrated hematologic response as evidenced by decreased circulating blasts. Four patients (20%) achieved complete remission. There was one treatment-related death. The combination of bortezomib and idarubicin in this mostly poor-risk, older AML group was well tolerated and did not result in high mortality. This trial was registered at www.clinicaltrials.gov as #NCT00382954.