A clinical study to evaluate efficacy of eplerenone, a new drug for the treatment of acute heart failure while protecting myocardium (a randomized, double-blind, placebo-controlled study)

INTERVENTION: Intervention type:DRUG. Intervention1:SC‐66110, Dose form:TABLET, Route of administration:ORAL. Control intervention1:placebo, Dose form:TABLET, Route of administration:ORAL. CONDITION: acute heart failure PRIMARY OUTCOME: Incidence of combined end point (cardiac death or first re‐hospitalization due to cardiac disease) within 6 months from the enrollment. Timepoint:6 months. SECONDARY OUTCOME: 1) Incidence of combined end point (cardiac death or first re‐hospitalization due to cardiac disease) (within 1 month from the enrollment). Timepoint: 6 months. INCLUSION CRITERIA: 1. Evidence of an informed consent document personally signed and dated by the patient 2. Japanese men and women whose age is 20 years or older at the time of giving the consent; 3. Patients with clinical evidence of acute heart failure, at no earlier than the date of visit and within 3 days of enrollment, demonstrated by at least one of the following ([1] De novo acute heart failure, [2] Acute exacerbation of chronic heart failure, [3] Post‐AMI heart failure applicable to [1]) 4. Patients whose left ventricular ejection fraction (LVEF) is 40% or less, at no earlier than the date of visit and within 72 hours of enrollment 5. Study subjects who are women must; (i) Be tested negative for serum or urine pregnancy test prior to randomization (except for women who have undergone panhysterectomy, or are 66 years or older, or have had menopause in the past 24 months or longer); and (ii) Provide consent to use effective contraceptive method during the stud