Progesterone

INDICATIONS AND USAGE Progesterone capsules are indicated for use in the prevention of endometrial hyperplasia in nonhysterectomized postmenopausal women who are receiving conjugated estrogens tablets. They are also indicated for use in secondary amenorrhea.

CLINICAL PHARMACOLOGY Progesterone capsules are an oral dosage form of micronized progesterone which is chemically identical to progesterone of ovarian origin. The oral bioavailability of progesterone is increased through micronization. Pharmacokinetics A. Absorption After oral administration of progesterone as a micronized soft-gelatin capsule formulation, maximum serum concentrations were attained within 3 hours. The absolute bioavailability of micronized progesterone is not known. Table 1 summarizes the mean pharmacokinetic parameters in postmenopausal women after five oral daily doses of progesterone capsules 100 mg as a micronized soft-gelatin capsule formulation. TABLE 1. Pharmacokinetic Parameters of Progesterone Parameter Progesterone capsules Daily Dose 100 mg 200 mg 300 mg a Mean ± S.D. C max (ng/mL) 17.3 ± 21.9 a 38.1 ± 37.8 60.6 ± 72.5 T max (hr) 1.5 ± 0.8 2.3 ± 1.4 1.7 ± 0.6 AUC (0-10) (ng × hr/mL) 43.3 ± 30.8 101.2 ± 66.0 175.7 ± 170.3 Serum progesterone concentrations appeared linear and dose proportional following multiple dose administration of progesterone capsules 100 mg over the dose range 100 mg/day to 300 mg/day in postmenopausal women. Although doses greater than 300 mg/day were not studied in females, serum concentrations from a study in male volunteers appeared linear and dose proportional between 100 mg/day and 400 mg/day. The pharmacokinetic parameters in male volunteers were generally consistent with those seen in postmenopausal women. B. Distribution Progesterone is approximately 96 percent to 99 percent bound to serum proteins, primarily to serum albumin (50 to 54 percent) and transcortin (43 to 48 percent). C. Metabolism Progesterone is metabolized primarily by the liver largely to pregnanediols and pregnanolones. Pregnanediols and pregnanolones are conjugated in the liver to glucuronide and sulfate metabolites. Progesterone metabolites which are excreted in the bile may be deconjugated and may be further metabolized in the gut via reduction, dehydroxylation, and epimerization. D. Excretion The glucuronide and sulfate conjugates of pregnanediol and pregnanolone are excreted in the bile and urine. Progesterone metabolites are eliminated mainly by the kidneys. Progesterone metabolites which are excreted in the bile may undergo enterohepatic recycling or may be excreted in the feces. E. Special Populations The pharmacokinetics of progesterone capsules have not been assessed in low body weight or obese patients. Hepatic Insufficiency: The effect of hepatic impairment on the pharmacokinetics of progesterone capsules has not been studied. Renal Insufficiency: The effect of renal impairment on the pharmacokinetics of progesterone capsules has not been studied. F. Food–Drug Interaction Concomitant food ingestion increased the bioavailability of progesterone capsules relative to a fasting state when administered to postmenopausal women at a dose of 200 mg. G. Drug Interactions The metabolism of progesterone by human liver mi

DOSAGE AND ADMINISTRATION Prevention of Endometrial Hyperplasia Progesterone capsules should be given as a single daily dose at bedtime, 200 mg orally for 12 days sequentially per 28-day cycle, to postmenopausal women with a uterus who are receiving daily conjugated estrogens tablets. Treatment of Secondary Amenorrhea Progesterone capsules may be given as a single daily dose of 400 mg at bedtime for 10 days. Some women may experience difficulty swallowing progesterone capsules. For these women, progesterone capsules should be taken with a glass of water while in the standing position.

ADVERSE REACTIONS See BOXED WARNING , WARNINGS and PRECAUTIONS. Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In a multicenter, randomized, double-blind, placebo-controlled clinical trial, the effects of progesterone capsules on the endometrium was studied in a total of 875 postmenopausal women. Table 6 lists adverse experiences greater than or equal to 2 percent of women who received cyclic progesterone capsules, 200 mg daily (12 days per calendar month cycle) with 0.625 mg conjugated estrogens or placebo. Table 6. Adverse Experiences (≥2%) Reported in an 875 Patient Placebo-Controlled Trial in Postmenopausal Women Over a 3-Year Period [Percentage (%) of Patients Reporting] Progesterone capsules 200 mg with Congugated Estrogens 0.625 mg Placebo (n=178) (n=174) Headache 31 27 Breast Tenderness 27 6 Joint Pain 20 29 Depression 19 12 Dizziness 15 9 Abdominal Bloating 12 5 Hot Flashes 11 35 Urinary Problems 11 9 Abdominal Pain 10 10 Vaginal Discharge 10 3 Nausea / Vomiting 8 7 Worry 8 4 Chest Pain 7 5 Diarrhea 7 4 Night Sweats 7 17 Breast Pain 6 2 Swelling of Hands and Feet 6 9 Vaginal Dryness 6 10 Constipation 3 2 Breast Carcinoma 2 <1 Breast Excisional Biopsy 2 <1 Cholecystectomy 2 <1 Effects on Secondary Amenorrhea In a multicenter, randomized, double-blind, placebo-controlled clinical trial, the effects of progesterone on secondary amenorrhea was studied in 49 estrogen-primed postmenopausal women. Table 7 lists adverse experiences greater than or equal to 5 percent of women who received progesterone or placebo. Table 7. Adverse Experiences (5%) Reported in Patients Using 400 mg/day in a Placebo-Controlled Trial in Estrogen-Primed Postmenopausal Women Adverse Experience Progesterone Capsules 400 mg Placebo n=25 n=24 Percentage (%) of Patients Fatigue 8 4 Headache 16 8 Dizziness 24 4 Abdominal Distention (Bloating) 8 8 Abdominal Pain (Cramping) 20 13 Diarrhea 8 4 Nausea 8 0 Back Pain 8 8 Musculoskeletal Pain 12 4 Irritability 8 4 Breast Pain 16 8 Infection Viral 12 0 Coughing 8 0 In a multicenter, parallel-group, open label postmarketing dosing study consisting of three consecutive 28-day treatment cycles, 220 premenopausal women with secondary amenorrhea were randomized to receive daily conjugated estrogens therapy (0.625 mg conjugated estrogens) and progesterone capsules, 300 mg per day (n=113) or Progesterone capsules, 400 mg per day (n=107) for 10 days of each treatment cycle. Overall, the most frequently reported treatment-emergent adverse reactions, reported in greater than or equal to 5 percent of subjects, were nausea, fatigue, vaginal mycosis, nasopharyngitis, upper respiratory tract infection, headache, dizziness, breast tenderness, abdominal distension, acne, dysmenorrhea, mood swing, and urinary tract infection. Postmarketing Experience: The following additional adverse reactions have been reported with progesterone capsules. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate the frequency or establish a causal relationship to drug exposure. Genitourinary System: endometrial carcinoma, hypospadia, intra-uterine death, menorrhagia, menstrual disorder, metrorrhagia, ovarian cyst, spontaneous abortion. Cardiovascular: circulatory collapse, congenital heart disease (including ventricular septal defect and patent ductus arteriosus), hypertension, hypotension, tachycardia. Gastrointestinal: acute pancreatitis, cholestasis, cholestatic hepatitis, dysphagia, hepatic failure, hepatic necrosis, hepatitis, increased liver function tests (including alanine aminotransferase increased, aspartate aminotransferase increased, gamma­glutamyl transferase increased), jaundice, swollen tongue. Skin: alopecia, pruritus, urticaria. Eyes: blurre

WARNINGS See BOXED WARNING . 1. Cardiovascular disorders An increased risk of pulmonary embolism, deep vein thrombosis (DVT), stroke, and myocardial infarction has been reported with estrogen plus progestin therapy. Should any of these occur or be suspected, estrogen with progestin therapy should be discontinued immediately. Risk factors for arterial vascular disease (for example, hypertension, diabetes mellitus, tobacco use, hypercholesterolemia, and obesity) and/or venous thromboembolism (for example, personal history or family history of venous thromboembolism [VTE], obesity, and systemic lupus erythematosus) should be managed appropriately. a. Stroke In the Women’s Health Initiative (WHI) estrogen plus progestin substudy, a statistically significant increased risk of stroke was reported in women 50 to 79 years of age receiving daily CE (0.625 mg) plus MPA (2.5 mg) compared to women in the same age group receiving placebo (33 versus 25 per 10,000 women-years). The increase in risk was demonstrated after the first year and persisted. (See CLINICAL STUDIES .) Should a stroke occur or be suspected, estrogen plus progestin therapy should be discontinued immediately. b. Coronary Heart Disease In the WHI estrogen plus progestin substudy, there was a statistically non-significant increased risk of coronary heart disease (CHD) events (defined as nonfatal myocardial infarction [MI], silent MI, or CHD death) reported in women receiving daily CE (0.625 mg) plus MPA (2.5 mg) compared to women receiving placebo (41 versus 34 per 10,000 women-years). An increase in relative risk was demonstrated in year 1 and a trend toward decreasing relative risk was reported in years 2 through 5. (See CLINICAL STUDIES .) In postmenopausal women with documented heart disease (n = 2,763, average age 66.7 years), in a controlled clinical trial of secondary prevention of cardiovascular disease (Heart and Estrogen/Progestin Replacement Study [HERS]), treatment with daily CE (0.625 mg) plus MPA (2.5 mg) demonstrated no cardiovascular benefit. During an average follow-up of 4.1 years, treatment with CE plus MPA did not reduce the overall rate of CHD events in postmenopausal women with established coronary heart disease. There were more CHD events in the CE plus MPA-treated group than in the placebo group in year 1, but not during the subsequent years. Two thousand three hundred and twenty one (2,321) women from the original HERS trial agreed to participate in an open-label extension of HERS, HERS II. Average follow-up in HERS II was an additional 2.7 years, for a total of 6.8 years overall. Rates of CHD events were comparable among women in the CE plus MPA group and the placebo group in HERS, HERS II, and overall. c. Venous thromboembolism In the WHI estrogen plus progestin substudy, a statistically significant 2-fold greater rate of VTE (DVT and pulmonary embolism [PE]) was reported in women receiving daily CE (0.625 mg) plus MPA (2.5 mg) compared to women receiving placebo (35 versus 17 per 10,000 women-years) and PE. Statistically significant increases in risk for both DVT (26 versus 13 per 10,000 women-years) and PE (18 versus 8 per 10,000 women-years) were also demonstrated. The increase in VTE risk was observed during the first year and persisted. (See CLINICAL STUDIES .) Should a VTE occur or be suspected, estrogen plus progestin therapy should be discontinued immediately. If feasible, estrogens with progestins should be discontinued at least 4 to 6 weeks before surgery of the type associated with an increased risk of thromboembolism, or during periods of prolonged immobilization. 2. Malignant neoplasms a. Breast cancer The most important randomized clinical trial providing information about breast cancer in estrogen plus progestin users is the Women’s Health Initiative (WHI) substudy of daily CE (0.625 mg) plus MPA (2.5 mg). After a mean follow-up of 5.6 years, the estrogen plus progestin substudy reported an increased risk of breast cancer in women

CONTRAINDICATIONS Progesterone capsules should not be used in women with any of the following conditions: Progesterone capsules should not be used in patients with known hypersensitivity to its ingredients. Progesterone capsules contain peanut oil and should never be used by patients allergic to peanuts. Undiagnosed abnormal genital bleeding. Known, suspected, or history of breast cancer. Active deep vein thrombosis, pulmonary embolism or history of these conditions. Active arterial thromboembolic disease (for example, stroke and myocardial infarction), or a history of these conditions. Known liver dysfunction or disease. Known or suspected pregnancy.

OVERDOSAGE No studies on overdosage have been conducted in humans. In the case of overdosage, progesterone capsules should be discontinued and the patient should be treated symptomatically.