Rationale and Design of the Double-Blind, Randomized, Placebo-Controlled Multicenter Trial on Efficacy of Early Initiation of Eplerenone Treatment in Patients with Acute Heart Failure (EARLIER).

BACKGROUND AND AIMS: Aldosterone is one of the major factors to cause organ damage during an acute phase of heart failure (HF), and many reports have demonstrated that patients with acute decompensated HF (ADHF) have high blood aldosterone concentrations, and the high aldosterone concentrations predict poor prognosis in patients with HF. These findings suggest that eplerenone, an antagonist of aldosterone receptors may provide a new concept and strategy for the treatment of ADHF, protecting the heart and other organs during chronic phases, depending on the restoration of hemodynamic abnormalities. METHODS: EARLIER is an event-driven clinical trial with an estimated enrolment of 300 patients hospitalized with ADHF with reduced left ventricular ejection fraction. ADHF includes ischemic or non-ischemic HF, and patients can be enrolled within 72 h after the visit to the hospital. We randomize the patients taking standard therapies for ADHF to the eplerenone and placebo groups. Eplerenone, either 25 or 50 mg, is administered for 6 months in the eplerenone group, and the corresponding placebo is administered in the placebo group on top of the standard care. We set the primary endpoint as the incidence of the composite endpoint (cardiac death or first re-hospitalization due to cardiac disease) 6 months after the enrollment, and also check the quality of life, i.e., exercise capacity and safety features of eplerenone. CONCLUSION AND PERSPECTIVES: EARLIER is a clinical trial of eplerenone targeting ADHF and also the first multicenter investigator-initiated phase III trial in the cardiovascular field in Japan, funded by the Japanese government.

Comparison of two ethnic populations using distribution adjusted mean.

In similarly designed clinical trials conducted in different regions or a multiregional trial, we sometimes observe different mean responses between trials or regions due to differences in distributions of an ethnic factor. Uesaka et al. ( 2003 ) used adjusted means for covariate, the distribution adjusted mean, to deal with such a situation. This paper examines distributional properties of the distribution adjusted mean and shows its applicability to comparison of mean responses from clinical trials where the distribution of an ethnic factor is different between regions. A real example and simulation results are shown. The results of this paper enable us to evaluate the similarity of different responses in clinical trials from different ethnic populations.

Sample size allocation to regions in a multiregional trial.

The objective of a multiregional bridging trial is to show the efficacy of a drug in various global regions, and at the same time to evaluate the possibility of applying the overall trial results to each region. However, to apply overall results to a specific region, the result in that region should be consistent with either the overall results or the results of other regions. This article discusses methods of sample size allocation to regions by introducing statistical criteria for consistency between regional and overall results. Specifically, three rules of sample size allocation are discussed: (1) allocating equal size to all regions, (2) minimizing total sample size, and (3) minimizing the sample size of a specific region. Some total and regional sample sizes calculated under each allocation rule are illustrated.