The purpose of this trial is to determine the equivalence of 3 new formulations of a Premarin®/medroxyprogesterone acetate (MPA) combination tablet to the currently marketed dosage form (Prempro® [TM]). This study will be performed in healthy postmenopausal women. Each subject will participate in the study for approximately 14 weeks, including a screening evaluation within 3 weeks before the study, and four, 6-day, 5-night inpatient periods with at least a 21-day washout interval between each dose administration.

Inclusion

1. Healthy postmenopausal women aged 35 to 70.
2. Body mass index of 18 to 35 kg/m2, weight must be at least 50 kg.
3. Nonsmoker or smoker of fewer than 10 cigarettes/day.

Exclusion

1. History or presence of hypertension (>139 mm Hg systolic or >89 mm Hg diastolic). Can take up to 2 antihypertensive medications to keep blood pressure under control.
2. History within 1 year of study day 1 of alcohol or drug abuse.
3. Use of any investigational drug within 30 days before study day 1.