Activella 1.0 mg/0.5 mg is a single tablet for oral administration containing 1 mg of estradiol and 0.5 mg of norethindrone acetate and the following excipients: lactose monohydrate, starch (corn), copovidone, talc, magnesium stearate, hypromellose and triacetin.

Activella 0.5 mg/0.1 mg is a single tablet for oral administration containing 0.5 mg of estradiol and 0.1 mg of norethindrone acetate and the following excipients: lactose monohydrate, starch (corn), hydroxypropylcellulose, talc, magnesium stearate, hypromellose and triacetin.

Estradiol (E₂) is a white or almost white crystalline powder. Its chemical name is estra-1, 3, 5 (10)-triene-3, 17β-diol hemihydrate with the empirical formula of C₁₈H₂₄O₂, ½ H₂O and a molecular weight of 281.4. The structural formula of E₂ is as follows:

Norethindrone acetate (NETA) is a white or yellowish-white crystalline powder. Its chemical name is 17β-acetoxy-19-nor-17α-pregn-4-en-20-yn-3-one with the empirical formula of C₂₂H₂₈O₃ and molecular weight of 340.5. The structural formula of NETA is as follows:

Last updated on RxList: 9/29/2008

Activella 1.0 mg/0.5 mg and 0.5 mg/0.1 mg are indicated in women who have a uterus for the:

1. Treatment of moderate to severe vasomotor symptoms associated with menopause.

2. Prevention of postmenopausal osteoporosis. When prescribing solely for the prevention of postmenopausal osteoporosis, therapy should only be considered for women at significant risk of osteoporosis and non-estrogen medications should be carefully considered.

The mainstays for decreasing the risk of postmenopausal osteoporosis are weight bearing exercise, adequate calcium and vitamin D intake, and when indicated, pharmacologic therapy.

Postmenopausal women require an average of 1500 mg/day of elemental calcium. Therefore, when not contraindicated, calcium supplementation may be helpful for women with suboptimal dietary intake. Vitamin D supplementation of 400-800 IU/day may also be required to ensure adequate daily intake in postmenopausal women.

Activella 1.0 mg/0.5 mg is also indicated in women who have a uterus for the:

3. Treatment of moderate to severe symptoms of vulvar and vaginal atrophy associated with menopause. When used solely for the treatment of symptoms of vulvar and vaginal atrophy, topical vaginal products should be considered.

Use of estrogen, alone or in combination with a progestin, should be with the lowest effective dose and for the shortest duration consistent with treatment goals and risks for the individual woman. Patients should be re-evaluated periodically as clinically appropriate (e.g., 3 to 6 month intervals) to determine if treatment is still necessary (See BOXED WARNINGS and WARNINGS). For women who have a uterus, adequate diagnostic measures, such as endometrial sampling, when indicated, should be undertaken to rule out malignancy in cases of undiagnosed persistent or recurring abnormal vaginal bleeding.

Activella therapy consists of a single tablet to be taken once daily.

1.For the treatment of moderate to severe vasomotor symptoms associated with menopause, and the prevention of postmenopausal osteoporosis. When prescribing solely for the prevention of postmenopausal osteoporosis, therapy should only be considered for women at significant risk of osteoporosis and non-estrogen medications should be carefully considered.

• Activella 1.0 mg/0.5 mg
• Activella 0.5 mg/0.1 mg

2.For the treatment of moderate to severe symptoms of vulvar and vaginal atrophy. When used solely for the treatment of symptoms of vulvar and vaginal atrophy, topical vaginal products should be considered.

• Activella 1.0 mg/0.5 mg

Patients should be started at the lowest dose.

Activella 1.0 mg/0.5 mg is a white, film-coated tablet, engraved with NOVO 288 on one side and the APIS bull on the other. It is round, 6mm in diameter and bi-convex. (NDC 0169-5174-02). It is supplied as 28 tablets in a calendar dial pack dispenser. Store in a dry place protected from light.

Activella 0.5 mg/0.1 mg is a white, film-coated tablet, engraved with NOVO 291 on one side and the APIS bull on the other. It is round, 6mm in diameter and bi-convex. (NDC 0169-5175-10). It is supplied as 28 tablets in a calendar dial pack dispenser. Keep the container in the outer carton.

Store at 25° C (77° F), excursions permitted to 15-30° C (59-86° F). [See USP Controlled Room Temperature.]

Revised December 2006. Novo Nordisk Inc. Princeton, NJ 08540. 1-866-668-6336. www.novonordisk-us.com. Manufactured by Novo Nordisk A/S 2880 Bagsvaerd, Denmark. FDA Rev date: 12/28/2006

Last updated on RxList: 9/29/2008

See BOXED WARNINGS, 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. The adverse reaction information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates.

Adverse events reported with Activella 1.0 mg/0.5 mg by investigators in the Phase 3 studies regardless of causality assessment are shown in Table 6.

TABLE 6: ALL TREATMENT-EMERGENT ADVERSE EVENTS REGARDLESS OF RELATIONSHIP REPORTED AT A FREQUENCY OF ≥ 5% WITH ACTIVELLA 1.0 MG/0.5 MG

	Endometrial Hyperplasia Study (12-Months)		Vasomotor Symptoms Study (3-Months)		Osteoporosis Study (2years)
	Activella 1.0 mg/0.5 mg (n=295)	1 mg E2 (n=296)	Activella 1.0 mg/0.5 mg (n=29)	Placebo (n=34)	Activella 1.0 mg/0.5 mg (n=47)	Placebo (n=48)
Body as a Whole
Back Pain	6%	5%	3%	3%	6%	4%
Headache	16%	16%	17%	18%	11%	6%
Digestive System
Nausea	3%	5%	10%	0%	11%	0%
Gastroenteritis	2%	2%	0%	0%	6%	4%
Nervous System
Insomnia	6%	4%	3%	3%	0%	8%
Emotional   Lability	1%	1%	0%	0%	6%	0%
Respiratory System
Upper Respiratory Tract Infection	18%	15%	10%	6%	15%	19%
Sinusitis	7%	11%	7%	0%	15%	10%
Metabolic and Nutritional
Weight Increase	0%	0%	0%	0%	9%	6%
Urogenital System
Breast Pain	24%	10%	21%	0%	17%	8%
Post-Menopausal Bleeding	5%	15%	10%	3%	11%	0%
Uterine Fibroid	5%	4%	0%	0%	4%	8%
Ovarian Cyst	3%	2%	7%	0%	0%	8%
Resistance mechanism
Infection Viral	4%	6%	0%	3%	6%	6%
Moniliasis Genital	4%	7%	0%	0%	6%	0%
Secondary Terms
Injury Accidental	4%	3%	3%	0%	17%*	4%*
Other Events	2%	3%	3%	0%	6%	4%
* including one upper extremity fracture in each group

Adverse events reported with Activella 0.5 mg/0.1 mg by investigators during the Phase 3 study regardless of causality assessment are shown in Table 7.

TABLE 7: ALL TREATMENT-EMERGENT ADVERSE EVENTS REGARDLESS OF RELATIONSHIP REPORTED AT A FREQUENCY OF ≥ 5% WITH ACTIVELLA 0.5 MG/0.1 MG

	Activella 0.5 mg/0.1 mg (n=194)	Placebo (n=200)
Body as a Whole
Back Pain	10%	4%
Headache	22%	19%
Pain in extremity	5%	4%
Digestive System
Nausea	5%	4%
Diarrhea	6%	6%
Respiratory System
Nasopharyngitis	21%	18%
Urogenital System
Endometrial thickening	10%	4%
Vaginal hemorrhage	26%	12%

The following adverse reactions have been reported with estrogen and/or progestin therapy:

Genitourinary system

Changes in vaginal bleeding pattern and abnormal withdrawal bleeding or flow; breakthrough bleeding; spotting; dysmenorrhea, increase in size of uterine leiomyomata; vaginitis, including vaginal candidiasis; change in amount of cervical secretion; changes in cervical ectropion; premenstrual-like syndrome; cystitis-like syndrome; ovarian cancer; endometrial hyperplasia; endometrial cancer.

Breasts

Tenderness, enlargement, pain, nipple discharge, galactorrhea; fibrocystic breast changes; breast cancer.

Cardiovascular

Deep and superficial venous thrombosis; pulmonary embolism; thrombophlebitis; myocardial infarction, stroke; increase in blood pressure.

Gastrointestinal

Nausea, vomiting; changes in appetite; cholestatic jaundice; abdominal pain/cramps, flatulence, bloating; increased incidence of gallbladder disease; pancreatitis; enlargement of hepatic hemangiomas.

Skin

Chloasma or melasma that may persist when drug is discontinued; erythema multiforme; erythema nodosum; hemorrhagic eruption; loss of scalp hair; seborrhea; hirsutism; itching; skin rash; pruritus.

Eyes

Retinal vascular thrombosis, intolerance to contact lenses.

Central nervous system

Headache; migraine; dizziness; mental depression; chorea; insomnia; nervousness; mood disturbances; irritability; exacerbation of epilepsy; probable dementia.

Miscellaneous

Increase or decrease in weight; aggravation of porphyria; edema; leg cramps; changes in libido; fatigue; reduced carbohydrate tolerance; anaphylactoid/anaphylactic reactions; hypocalcemia; exacerbation of asthma; increased triglycerides; back pain; arthralgia; myalgia.

Drug/Laboratory Test Interactions

1. Accelerated prothrombin time, partial thromboplastin time, and platelet aggregation time; increased platelet count; increased factors II, VII antigen, VIII coagulant activity, IX, X, XII, VII-X complex, and beta-thromboglobulin; decreased levels of anti-factor Xa and antithrombin III, decreased antithrombin III activity, increased levels of fibrinogen and fibrinogen activity; increased plasminogen antigen and activity.
2. Increased thyroid-binding globulin (TBG) levels leading to increased circulating total thyroid hormone levels as measured by protein-bound iodine (PBI), T4 levels (by column or by radioimmunoassay), or T₃ levels by radioimmunoassay. T₃ resin uptake is decreased, reflecting the elevated TBG. Free T₄ and free T₃ concentrations are unaltered. Patients on thyroid replacement therapy may require higher doses of thyroid hormone.
3. Other binding proteins may be elevated in serum (i.e., corticosteroid binding globulin (CBG), SHBG) leading to increased total circulating corticosteroids and sex steroids, respectively. Free hormone concentrations may be decreased. Other plasma proteins may be increased (angiotensinogen/rennin substrate, alpha-1 antitrypsin, ceruloplasmin).
4. Increased plasma HDL and HDL₂cholesterol subfraction concentration, reduced LDL cholesterol concentration, increased triglyceride levels.
5. Impaired glucose tolerance.
6. Reduced response to metyrapone test.

Last updated on RxList: 9/29/2008

See BOXED WARNINGS.

Cardiovascular disorders

Estrogen-plus-progestin therapy has been associated with an increased risk of myocardial infarction as well as stroke, venous thrombosis and pulmonary embolism.

Estrogen-alone therapy has been associated with an increased risk of stroke and deep vein thrombosis (DVT). Should any of these events occur or be suspected, estrogens should be discontinued immediately.

Risk factors for arterial vascular disease (e.g., hypertension, diabetes mellitus, tobacco use, hypercholesterolemia, and obesity) and/or venous thromboembolism (e.g., personal history or family history of VTE, obesity, and systemic lupus erythematosus) should be managed appropriately.

Stroke

In the estrogen plus progestin substudy of the Women's Health Initiative (WHI), a statistically significant increased risk of stroke was reported in women receiving CE/MPA 0.625mg/2.5mg daily compared to woman receiving placebo (31 vs. 24 per 10,000 women-years). The increase in risk was demonstrated after the first year and persisted. (See Clinical Studies.)

In the estrogen-alone substudy of the WHI, a statistically significant increased risk of stroke was reported in women receiving CE 0.625 mg daily compared to women receiving placebo (44 vs. 32 per 10,000 women-years). The increase in risk was demonstrated in year one and persisted.

Coronary heart disease

In the estrogen-plus progestin sub-study of WHI, no statistically significant increase in CHD events (defined as non-fatal, MI, silent MI, or death, due to CHD) was reported in women receiving CE/MPA compared to women receiving placebo (39 vs. 33 per 10,000 women-years). An increase in relative risk was demonstrated in year one, and a trend toward decreasing relative risk was reported in years 2 through 5. (See Clinical Studies.)

In the estrogen-alone substudy of WHI, no overall effect on coronary disease (CHD) events was reported in women receiving estrogen alone compared to placebo. (See Clinical Studies.)

In postmenopausal women with documented heart disease (n=2,763, average age 66.7 years), a controlled clinical trial of secondary prevention of cardiovascular disease (Heart and Estrogen/Progestin Replacement Study (HERS)) treatment with CE/MPA (0.625mg/2.5mg per day) demonstrated no cardiovascular benefit. During an average follow-up of 4.1 years, treatment with CE/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/MPA-treated group than in the placebo group in year 1, but not during the subsequent years. Participation in an open-label extension of the original HERS trial (HERS II) was agreed to by 2,321 women. 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/MPA group and the placebo group in HERS, HERS II, and overall.

Large doses of estrogen (5 mg conjugated estrogens per day), comparable to those used to treat cancer of the prostate and breast, have been shown in a large prospective clinical trial in men to increase the risk of nonfatal myocardial infarction, pulmonary embolism, and thrombophlebitis.

Venous thromboembolism

In the estrogen-plus-progestin substudy of the Women's Health Initiative (WHI), a statistically significant 2-fold greater rate of VTE (DVT and pulmonary embolism [PE]), was reported in women receiving CE/MPA compared to women receiving placebo (35 vs. 17 per 10,000 women-years). Statistically significant increases in risk for both DVT (26 vs. 13 per 10,000 women-years) and PE (18 vs. 8 per 10,000 women-years) were also demonstrated. The increase in VTE risk was demonstrated during the first year and persisted. (See Clinical Studies.) In the estrogen-alone substudy of WHI, the risk of VTE was reported to be increased for women taking conjugated estrogens (30 vs. 22 per 10,000 women-years), although only the increased risk of DVT reached statistical significance (23 vs. 15 per 10,000 women-years). The increase in VTE risk was demonstrated during the first two years.

If feasible, estrogens 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.

Malignant neoplasms

Breast cancer

In some studies, the use of estrogens and progestins by postmenopausal women has been reported to increase the risk of breast cancer. The most important randomized clinical trial providing information about this issue is the CE/MPA substudy of the WHI study (see Clinical Studies). The results from observational studies are generally consistent with those of the WHI clinical trial.

Observational studies have also reported an increased risk of breast cancer for estrogen-plus-progestin combination therapy, and a smaller increased risk for estrogen-alone therapy, after several years of use. For both findings, the excess risk increased with duration of use, and appeared to return to baseline over about five years after stopping treatment (only the observational studies have substantial data on risk after stopping). In these studies, the risk of breast cancer was greater, and became apparent earlier, with estrogen-plus-progestin combination therapy as compared to estrogen-alone therapy. However, these studies have not found significant variation in the risk of breast cancer among different estrogens or among different estrogen-plus-progestin combinations, doses, or routes of administration.

In the estrogen-plus-progestin substudy, after a mean follow-up of 5.6 years, the WHI substudy reported an increased risk of breast cancer. In this substudy, prior use of estrogen alone or estrogen-plus-progestin combination hormone therapy was reported by 26% of the women. The relative risk of invasive breast cancer was 1.24 (95% nCI 1.01-1.54), and the absolute risk was 41 vs. 33 cases per 10,000 women-years, for estrogen plus progestin compared with placebo, respectively. Among women who reported prior use of hormone therapy, the relative risk of invasive breast cancer was 1.86, and the absolute risk was 46 vs. 25 cases per 10,000 women-years, for estrogen plus progestin compared with placebo. Among women who reported no prior use of hormone therapy, the relative risk of invasive breast cancer was 1.09, and the absolute risk was 40 vs. 36 cases per 10,000 women-years of estrogen plus progestin compared with placebo. In the WHI trial, invasive breast cancers were larger and diagnosed at a more advanced stage in the estrogen-plus-progestin group compared with the placebo group. Metastatic disease was rare, with no apparent difference between the two groups. Other prognostic factors, such as histologic subtype, grade and hormone receptor status did not differ between the groups.

In the estrogen-alone substudy of WHI, after an average of 7.1 years of follow-up, CE (0.625 mg daily) was not associated with an increased risk of invasive breast cancer (RR 0.80, 95% nCI 0.62-1.04).

In a one-year trial among 1,176 women who received either unopposed 1 mg estradiol or a combination of 1 mg estradiol plus one of three different doses of NETA (0.1, 0.25, and 0.5 mg), seven new cases of breast cancer were diagnosed, two of which occurred among the group of 295 women treated with Activella 1.0 mg/0.5 mg and two of which occurred among the group of 294 women treated with 1 mg estradiol/0.1 mg NETA.

The use of estrogen alone and estrogen plus progestin has been reported to result in an increase in abnormal mammograms requiring further evaluation. All women should receive yearly breast examinations by a health care provider and perform monthly breast self-examinations. In addition, mammography examinations should be scheduled based on patient age, risk factors, and prior mammogram results.

Endometrial cancer

The use of unopposed estrogens in women with intact uteri has been associated with an increased risk of endometrial cancer. The reported endometrial cancer risk among unopposed estrogen users is about 2 to 12 fold greater than in nonusers, and appears dependent on duration of treatment and on estrogen dose. Most studies show no significant increased risk associated with use of estrogens for less than one year. The greatest risk appears associated with prolonged use, with an increased risk of 15- to 24-fold for five to ten years or more. This risk has been shown to persist for at least 8 to 15 years after estrogen therapy is discontinued.

Clinical surveillance of all women taking estrogen/progestin combinations is important. Adequate diagnostic measures, including endometrial sampling when indicated, should be undertaken to rule out malignancy in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding. There is no evidence that the use of natural estrogens results in a different endometrial risk profile than synthetic estrogens of equivalent estrogen dose. Adding a progestin to estrogen therapy has been shown to reduce the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer.

Endometrial hyperplasia (a possible precursor of endometrial cancer) has been reported to occur in approximately 1% or less with Activella in one large clinical trial.

Dementia

In the estrogen-plus-progestin Women's Health Initiative Memory Study (WHIMS), a substudy of WHI, a population of 4,532 postmenopausal women aged 65 to 79 years was randomized to CE/MPA (0.625 mg/2.5 mg daily) or placebo. In the estrogen-alone WHIMS substudy, a population of 2,947 hysterectomized women, aged 65 to 79 years, was randomized to CE (0.625 mg daily) or placebo.

In the estrogen-plus-progestin substudy, after an average follow-up of four years, 40 women in the estrogen-plus-progestin group and 21 women in the placebo group were diagnosed with probable dementia. The relative risk of probable dementia for estrogen plus progestin vs. placebo was 2.05 (95% CI 1.21-3.48). The absolute risk of probable dementia for CE/MPA vs. placebo was 45 vs. 22 cases per 10,000 women-years.

In the estrogen-alone substudy, after an average follow-up of 5.2 years, 28 women in the estrogen-alone group and 19 women in the placebo group were diagnosed with probable dementia. The relative risk of probable dementia for CE alone vs. placebo was 1.49 (95% CI 0.83-2.66). The absolute risk of probable dementia for CE alone vs. placebo was 37 vs. 25 cases per 10,000 women-years.

When data from the two populations were pooled as planned in the WHIMS protocol, the reported overall relative risk of probable dementia was 1.76 (95% CI 1.19-2.60). Since both substudies were conducted in women ages 65 to 79, it is unknown whether these findings apply to younger postmenopausal women. (See BOXED WARNINGS and PRECAUTIONS, Geriatric Use.)

Gallbladder disease

A two-to four fold increase in the risk of gallbladder disease requiring surgery in postmenopausal women receiving estrogens has been reported.

Hypercalcemia

Estrogen administration may lead to severe hypercalcemia in patients with breast cancer and bone metastases. If hypercalcemia occurs, use of the drug should be stopped and appropriate measures taken to reduce the serum calcium level.

Visual abnormalities

Retinal vascular thrombosis has been reported in patients receiving estrogens. Discontinue medication pending examination if there is a sudden partial or complete loss of vision, or a sudden onset of proptosis, diplopia, or migraine. If examination reveals papilledema or retinal vascular lesions, estrogens should be permanently discontinued.

General

Addition of a progestin when a woman has not had a hysterectomy

Studies of the addition of a progestin for 10 or more days of a cycle of estrogen administration, or daily with estrogen in a continuous regimen, have reported a lowered incidence of endometrial hyperplasia than would be induced by estrogen treatment alone. Endometrial hyperplasia may be a precursor to endometrial cancer.

There are, however, possible risks that may be associated with the use of progestins with estrogens compared to estrogen-alone treatment. These include a possible increased risk of breast cancer.

Elevated blood pressure

In a small number of case reports, substantial increases in blood pressure have been attributed to idiosyncratic reactions to estrogens. In a large, randomized, placebo-controlled clinical trial, a generalized effect of estrogens on blood pressure was not seen. Blood pressure should be monitored at regular intervals with estrogen use.

Hypertriglyceridemia

In patients with preexisting hypertriglyceridemia, estrogen therapy may be associated with elevations of plasma triglycerides leading to pancreatitis and other complications.

Impaired liver function and past history of cholestatic jaundice

Estrogens may be poorly metabolized in patients with impaired liver function. For patients with a history of cholestatic jaundice associated with past estrogen use or with pregnancy, caution should be exercised, and in the case of recurrence, medication should be discontinued.

Hypothyroidism

Estrogen administration leads to increased thyroid-binding globulin (TBG) levels. Patients with normal thyroid function can compensate for the increased TBG by making more thyroid hormone, thus maintaining free T4 and T3 serum concentrations in the normal range. Patients dependent on thyroid hormone replacement therapy who are also receiving estrogen may require increased doses of their thyroid replacement therapy. These patients should have their thyroid function monitored to maintain their free thyroid hormone levels in an acceptable range.

Fluid retention

Estrogens may cause some degree of fluid retention. Because of this, patients who have conditions that might be influenced by this factor, such as a cardiac or renal dysfunction, warrant careful observation when estrogens are prescribed.

Hypocalcemia

Estrogens should be used with caution in individuals with severe hypocalcemia.

Ovarian cancer

The estrogen-plus-progestin substudy of WHI reported that after an average follow-up of 5.6 years, the relative risk for ovarian cancer for estrogen plus progestin vs. placebo was 1.58 (95% CI 0.77 - 3.24), but was not statistically significant. The absolute risk for estrogen plus progestin vs. placebo was 4.2 vs. 2.7 cases per 10,000 women-years. In some epidemiologic studies, the use of estrogen-only products, in particular for 10 or more years, has been associated with an increased risk of ovarian cancer. Other epidemiologic studies have not found these associations.

Exacerbation of endometriosis

Endometriosis may be exacerbated with administration of estrogens.

Malignant transformation of residual endometrial implants has been reported in women treated post-hysterectomy with estrogen-alone therapy. For patients known to have residual endometriosis post-hysterectomy, the addition of progestin should be considered.

Exacerbation of other conditions

Estrogens may cause an exacerbation of asthma, diabetes mellitus, epilepsy, migraine or porphyria, systemic lupus erythematosus, and hepatic hemangiomas and should be used with caution in women with these conditions.

Laboratory Tests

Estrogen administration should be initiated at the lowest dose approved for the indication and then guided by clinical response, rather than by serum hormone levels (e.g., estradiol, FSH).

Carcinogenesis, Mutagenesis, Impairment of Fertility

Long-term continuous administration of estrogen, with or without progestin, in women with or without a uterus, has shown an increased risk of endometrial cancer, breast cancer, and ovarian cancer. (See BOXED WARNINGS, WARNINGS, and PRECAUTIONS.)

Long-term continuous administration of natural and synthetic estrogens in certain animal species increases the frequency of carcinomas of the breast, uterus, cervix, vagina, testis, and liver.

Pregnancy

Activella should not be used during pregnancy. (See CONTRAINDICATIONS.)

Nursing Mothers

Estrogen administration to nursing mothers has been shown to decrease the quantity and quality of breast milk. Detectable amounts of estrogens have been identified in the milk of mothers receiving this drug. Caution should be exercised when Activella is administered to a nursing mother.

Pediatric Use

Activella is not indicated in children.

Geriatric Use

Clinical studies of Activella did not include sufficient number of subjects aged 65 and over to determine if they responded differently from younger subjects.

Of the total number of subjects in the estrogen-plus-progestin substudy of the Women's Health Initiative (WHI) study, 44% (n=7,320) were 65-74 years of age, while 6.6% (n=1,095) were 75 years and over. There was a higher relative risk (CE/MPA vs. placebo) of non-fatal stroke and invasive breast cancer in women 75 and over compared to women less than 75 years of age. In women greater than 75, the increased risk of non-fatal stroke and invasive breast cancer observed in the estrogen-plus-progestin combination group compared to the placebo group was 75 vs. 24 per 10,000 women-years and 52 vs. 12 per 10,000 women-years, respectively.

In the estrogen-plus-progestin Women's Health Initiative Memory Study (WHIMS), a substudy of WHI, a population of 4,532 hysterectomized women, aged 65 to 79 years, was randomized to CE/MPA (0.625 mg/2.5 mg daily) or placebo. In the estrogen-plus-progestin group, after an average follow-up of four years, the relative risk (CE/MPA vs. placebo) of probable dementia was 2.05 (95% CI 1.21-3.48). The absolute risk of developing probable dementia with CE/MPA was 45 vs. 22 cases per 10,000 women-years with placebo.

Of the total number of subjects in the estrogen-alone substudy of WHI, 46% (n=4,943) were 65 years and over, while 7.1% (n=767) were 75 years and over. There was a higher relative risk (CE vs. placebo) of stroke in women less than 75 years of age compared to women 75 years and over. In the estrogen-alone WHIMS substudy, a population of 2,947 hysterectomized women, aged 65 to 79 years, was randomized to CE (0.625 mg daily) or placebo. After an average follow-up of 5.2 years, the relative risk (CE vs. placebo) of probable dementia was 1.49 (95% CI 0.83-2.66). The absolute risk of developing probable dementia with estrogen alone was 37 vs. 25 cases per 10,000 women-years with placebo.

Seventy-nine percent of the cases of probable dementia occurred in women that were older than 70 for the CE-alone group, and 82 percent of the cases of probable dementia occurred in women who were older than 70 in the CE/MPA group. The most common classification of probable dementia in both the treatment groups and placebo groups was Alzheimer's disease.

When data from the two populations were pooled as planned in the WHIMS protocol, the reported overall relative risk for probable dementia was 1.76 (95% CI 1.19-2.60). Since both substudies were conducted in women aged 65 to 79 years, it is unknown whether these findings apply to younger postmenopausal women. (See BOXED WARNINGS and WARNINGS, Dementia.)

Last updated on RxList: 9/29/2008

Serious ill effects have not been reported following acute ingestion of large doses of estrogen-containing drug products by young children. Overdosage of estrogen may cause nausea and vomiting, and withdrawal bleeding may occur in females.

Activella should not be used in women with any of the following conditions:

1. Undiagnosed abnormal genital bleeding.
2. Known, suspected, or history of cancer of the breast.
3. Known or suspected estrogen-dependent neoplasia.
4. Active deep vein thrombosis, pulmonary embolism, or history of these conditions.
5. Active or recent (e.g., within the past year) arterial thromboembolic disease (e.g., stroke, myocardial infarction).
6. Liver dysfunction or disease.
7. Known hypersensitivity to the ingredients of Activella 1.0 mg/0.5 mg or Activella 0.5 mg/0.1 mg.
8. Known or suspected pregnancy. There is no indication for Activella in pregnancy. There appears to be little or no increased risk of birth defects in children born to women who have used estrogens and progestins from oral contraceptives inadvertently during early pregnancy. (See PRECAUTIONS.)

Last updated on RxList: 9/29/2008

Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level.

The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of estradiol daily, depending on the phase of the menstrual cycle. After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone by peripheral tissues. Thus, estrone and the sulfate conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women.

Estrogens act through binding to nuclear receptors in estrogen-responsive tissues. To date, two estrogen receptors have been identified. These vary in proportion from tissue to tissue.

Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) through a negative feedback mechanism. Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.

Progestin compounds enhance cellular differentiation and generally oppose the actions of estrogens by decreasing estrogen receptor levels, increasing local metabolism of estrogens to less active metabolites, or inducing gene products that blunt cellular responses to estrogen. Progestins exert their effects in target cells by binding to specific progesterone receptors that interact with progesterone response elements in target genes. Progesterone receptors have been identified in the female reproductive tract, breast, pituitary, hypothalamus, and central nervous system. Progestins produce similar endometrial changes to those of the naturally occurring hormone progesterone.

Pharmacokinetics

Absorption

Estradiol is well absorbed through the gastrointestinal tract. Following oral administration of Activella tablets, peak plasma estradiol concentrations are reached slowly within 5-8 hours. When given orally, estradiol is extensively metabolized (first-pass effect) to estrone sulfate, with smaller amounts of other conjugated and unconjugated estrogens. After oral administration, norethindrone acetate is rapidly absorbed and transformed to norethindrone. It undergoes first-pass metabolism in the liver and other enteric organs, and reaches a peak plasma concentration within 0.5 - 1.5 hours after the administration of Activella tablets. The oral bioavailability of estradiol and norethindrone following administration of Activella 1.0 mg/0.5 mg when compared to a combination oral solution is 53% and 100%, respectively. Administration of Activella 1.0 mg/0.5 mg with food did not modify the bioavailability of estradiol, although increases in AUC_0-72 of 19% and decreases in Cmax of 36% for norethindrone were seen.

The pharmacokinetic parameters of estradiol (E₂), estrone (E₁), and norethindrone (NET) following oral administration of 1 Activella 1.0 mg/0.5 mg or 2 Activella 0.5 mg/0.1 mg tablet(s) to healthy postmenopausal women are summarized in Table 1.

TABLE 1: PHARMACOKINETIC PARAMETERS AFTER ADMINISTRATION OF 1 TABLET OF ACTIVELLA 1.0 MG/0.5 MG OR 2 TABLETS OF ACTIVELLA 0.5 MG/0.1 MG TO HEALTHY POSTMENOPAUSAL WOMEN

	1 x Activella 1.0 mg/0.5 mg (n=24) Meana (%CV)b	2 x Activella 0.5 mg/0.1 mg (n=24) Meana (%CV)b
Estradiolc (E2)
AUC0-t (pg/mL*h)	766.5 (48)	697.3 (53)
Cmax (pg/mL)	26.8 (36)	26.5 (37)
tmax(h): median (range)	6.0 (0.5-16.0)	6.5 (0.5-16.0)
t1/2(h)d	14.0e (29)	14.5f (27)
Estronec (E1)
AUC0-t (pg/mL*h)	4469.1 (48)	4506.4 (44)
Cmax (pg/mL)	195.5 (37)	199.5 (30)
tmax (h): median (range)	6.0 (1.0-9.0)	6.0 (2.0-9.0)
t1/2(h)d	10.7 (44)g	11.8 (25)g
Norethindrone (NET)
AUC0-t (pg/mL*h)	21043 (41)	8407.2 (43)
Cmax (pg/mL)	5249.5 (47)	2375.4 (41)
tmax (h) : median(range)	0.7 (0.7-1.25)	0.8 (0.7-1.3)
t1/2(h)	9.8 (32)h	11.4 (36)i
AUC = area under the curve, 0 - last quantifiable sample Cmax = maximum plasma concentration, tmax = time at maximum plasma concentration, t1/2 = half-life, a geometric mean; b geometric % coefficient of variation; c baseline unadjusted data; d baseline unadjusted data ; e n=18; f n=16; g n=13; h n=22; i n=21

Following continuous dosing with once-daily administration of Activella 1.0 mg/0.5 mg, serum levels of estradiol, estrone, and norethindrone reached steady-state within two weeks with an accumulation of 33-47% above levels following single dose administration. Unadjusted circulating levels of E₂, E₁, and NET during Activella 1.0 mg/0.5 mg treatment at steady state (dosing at time 0) are provided in Figures 1a and 1b.

Figure 1a: Levels of Estradiol and Estrone at Steady State During Continuous Dosing with Activella 1.0 mg/0.5 mg (n=24)

Figure 1b: Levels of Norethindrone at Steady State During Continuous Dosing with Activella 1.0 mg/0.5 mg (n=24)

Distribution

The distribution of exogenous estrogens is similar to that of endogenous estrogens. Estrogens are widely distributed in the body and are generally found in higher concentrations in the sex hormone target organs. Estradiol circulates in the blood bound to sex-hormone-binding globulin (SHBG) (37%) and to albumin (61%), while only approximately 1-2% is unbound. Norethindrone also binds to a similar extent to SHBG (36%) and to albumin (61%).

Metabolism

Estradiol: Exogenous estrogens are metabolized in the same manner as endogenous estrogens. Circulating estrogens exist in a dynamic equilibrium of metabolic interconversions. These transformations take place mainly in the liver. Estradiol is converted reversibly to estrone, and both can be converted to estriol, which is the major urinary metabolite. Estrogens also undergo enterohepatic recirculation via sulfate and glucuronide conjugation in the liver, biliary secretion of conjugates into the intestine, and hydrolysis in the intestine followed by reabsorption. In postmenopausal women, a significant proportion of the circulating estrogens exist as sulfate conjugates, especially estrone sulfate, which serves as a circulating reservoir for the formation of more active estrogens.

Norethindrone Acetate: The most important metabolites of norethindrone are isomers of 5α-dihydro-norethindrone and tetrahydro-norethindrone, which are excreted mainly in the urine as sulfate or glucuronide conjugates.

Excretion

Estradiol, estrone, and estriol are excreted in the urine along with glucuronide and sulfate conjugates. The half-life of estradiol following single dose administration of Activella 1.0 mg/0.5 mg is 12-14 hours. The terminal half-life of norethindrone is about 8-11 hours.

Special Populations

No pharmacokinetic studies were conducted in special populations, including patients with renal or hepatic impairment.

Drug Interactions

Coadministration of estradiol with norethindrone acetate did not elicit any apparent influence on the pharmacokinetics of norethindrone. Similarly, no relevant interaction of norethindrone on the pharmacokinetics of estradiol was found within the NETA dose range investigated in a single dose study.

In-vitro and in-vivo studies have shown that estrogens are metabolized partially by cytochrome P450 3A4 (CYP3A4). Therefore, inducers or inhibitors of CYP3A4 may affect estrogen drug metabolism. Inducers of CYP3A4 such as St. John's Wort preparations (Hypericum perforatum), phenobarbital, carbamazepine, and rifampin may reduce plasma concentrations of estrogens, possibly resulting in a decrease in therapeutic effects and/or changes in the uterine bleeding profile. Inhibitors of CYP3A4 such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir and grapefruit juice may increase plasma concentrations of estrogens and result in side effects.

Clinical Studies

Effects on Vasomotor Symptoms

In a 12-week randomized clinical trial involving 92 subjects, Activella 1.0 mg/0.5 mg was compared to 1 mg of estradiol and to placebo. The mean number and intensity of hot flushes were significantly reduced from baseline to week 4 and 12 in both the Activella 1.0 mg/0.5 mg and the 1 mg estradiol group compared to placebo (see Figure 2).

Figure 2: Mean Weekly Number of Moderate and Severe Hot Flushes in a 12-Week Study

In a study conducted in Europe a total of 577 postmenopausal women were randomly assigned to either Activella 0.5 mg/0.1 mg, 0.5 mg E₂/0.25 mg NETA, or placebo for 24 weeks of treatment. The mean number and severity of hot flushes were significantly reduced at week 4 and week 12 in the Activella 0.5 mg/0.1 mg (see Figure 3) and 0.5 mg E₂/0.25 mg NETA groups compared to placebo.

Figure 3: Mean Number of Moderate to Severe Hot Flushes for Weeks 0 Through 12

Effects on the Endometrium

Activella 1.0 mg/0.5 mg reduced the incidence of estrogen-induced endometrial hyperplasia at 1 year in a randomized, controlled clinical trial. This trial enrolled 1,176 subjects who were randomized to one of 4 arms: 1 mg estradiol unopposed (n=296), 1 mg E₂ + 0.1 mg NETA (n=294), 1 mg E₂ + 0.25 mg NETA (n=291), and Activella 1.0 mg/0.5 mg (n=295). At the end of the study, endometrial biopsy results were available for 988 subjects. The results of the 1 mg estradiol unopposed arm compared to Activella 1.0 mg/0.5 mg are shown in Table 2.

TABLE 2: INCIDENCE OF ENDOMETRIAL HYPERPLASIA WITH UNOPPOSED ESTRADIOL AND ACTIVELLA 1.0 MG/0.5 MG IN A 12-MONTH STUDY

	1 mg E2 (n=296)	Activella 1 mg E2/0.50mg NETA (n=295)	1 mg E2/0.25 mg NETA (n=291)	1 mg E2/0.1 mg NETA (n=294)
No. of subjects with histological evaluation at the end of the study	247	241	251	249
No. (%) of subjects with endometrial hyperplasia at the end of the study	36 (14.6%)	1 (0.4%)	1 (0.4%)	2 (0.8%)

Effects on Uterine Bleeding or Spotting

During the initial months of therapy, irregular bleeding or spotting occurred with Activella 1.0 mg/0.5 mg treatment. However, bleeding tended to decrease over time, and after 12 months of treatment with Activella 1.0 mg/0.5 mg, about 86% of women were amenorrheic (see Figure 4).

Figure 4: Patients Treated with Activella 1.0 mg/0.5 mg with Cumulative Amenorrhea over Time Percentage of Women with no Bleeding or Spotting at any Cycle Through Cycle 13 Intent to Treat Population, LOCF

Note: the percentage of patients who were amenorrheic in a given cycle and through cycle 13 is shown. If data were missing, the bleeding value from the last reported day was carried forward (LOCF).

In the clinical trial with Activella 0.5 mg/0.1 mg, 88% of women were amenorrheic after 6 months of treatment (See Figure 5).

Figure 5: Patients Treated with Activella 0.5 mg/0.1 mg with Cumulative Amenorrhea over Time Percentage of Women with no Bleeding or Spotting at any Cycle Through Cycle 6, Intent to Treat Population, LOCF

Effects on Bone Mineral Density

The results of two randomized, multicenter, calcium-supplemented (500-1000 mg/day), placebo-controlled, 2 year clinical trials have shown that Activella 1.0 mg/0.5 mg and estradiol 0.5 mg are effective in preventing bone loss in postmenopausal women. While Activella 0.5mg/0.1mg was not directly studied in these trials, the US trial showed that addition of NETA to estradiol enhances the effect on BMD, therefore the BMD changes expected from treatment with Activella 0.5mg/0.1mg should be at least as great as observed with estradiol 0.5mg. A total of 462 postmenopausal women with intact uteri and baseline BMD values for lumbar spine within 2 standard deviations of the mean in healthy young women were enrolled. In a US trial, 327 postmenopausal women (mean time from menopause 2.5 to 3.1 years) with a mean age of 53 years were randomized to 7 groups (0.25 mg, 0.5mg, and 1 mg of estradiol alone, 1 mg estradiol with 0.25 mg norethindrone acetate, 1 mg estradiol with 0.5 mg norethindrone acetate, and 2 mg estradiol with 1 mg norethindrone acetate, and placebo.) In a European trial (EU trial), 135 postmenopausal women (mean time from menopause 8.4 to 9.3 years) with a mean age of 58 years were randomized to 1 mg estradiol with 0.25 mg norethindrone acetate, 1 mg estradiol with 0.5 mg norethindrone acetate, and placebo. Approximately 58% and 67% of the randomized subjects in the two clinical trials, respectively, completed the two clinical trials. BMD was measured using dual-energy x-ray absorptiometry (DEXA).

A summary of the results comparing Activella 1.0 mg/0.5 mg and estradiol 0.5 mg to placebo from the two prevention trials is shown in Table 3.

TABLE 3: PERCENTAGE CHANGE (MEAN ± SD) IN BONE MINERAL DENSITY (BMD) FOR ACTIVELLA 1.0 MG/0.5 MG AND 0.5 MG E₂^† (Intent to Treat Analysis, Last Observation Carried Forward)

	US Trial			EU Trial
	Placebo (n=37)	0.5 mg E2† (n=31)	Activella 1.0 mg/0.5 mg (n=37)	Placebo (n=40)	Activella 1.0 mg/0.5 mg (n=38)
Lumbar spine	-2.1 ± 2.9	2.3 ± 2.8 *	3.8 ± 3.0 *	-0.9 ± 4.0	5.4 ± 4.8 *
Femoral neck	-2.3 ± 3.4	0.3 ± 2.9 **	1.8 ± 4.1 *	-1.0 ± 4.6	0.7 ± 6.1
Femoral trochanter	-2.0 ± 4.3	1.7 ± 4.1***	3.7 ± 4.3 *	0.8 ± 6.9	6.3 ± 7.6 *
US= United States, EU = European †While Activella 0.5mg/0.1mg was not directly studied in these trials, the US trial showed that addition of NETA to estradiol enhances the effect on BMD, therefore the BMD changes expected from treatment with Activella 0.5mg/0.1mg should be at least as great as observed with estradiol 0.5mg. * Significantly (p<0.001) different from placebo ** Significantly (p<0.007) different from placebo ***Significantly (p<0.002) different from placebo

The overall difference in mean percentage change in BMD at the lumbar spine in the US trial (1000 mg/day calcium) between Activella 1.0 mg/0.5 mg and placebo was 5.9% and between estradiol 0.5 mg and placebo was 4.4%. In the European trial (500 mg/day calcium), the overall difference in mean percentage change in BMD at the lumbar spine was 6.3%. Activella 1.0 mg/0.5 mg and estradiol 0.5 mg also increased BMD at the femoral neck and femoral trochanter compared to placebo. The increase in lumbar spine BMD in the US and European clinical trials for Activella 1.0 mg/0.5 mg and estradiol 0.5 mg is displayed in Figure 6.

Figure 6: Percentage Change in Bone Mineral Density (BMD) ± SEM of the Lumbar Spine (L1-L4) for Activella 1.0 mg/0.5 mg and Estradiol 0.5 mg^† (Intent to Treat Analysis with Last Observation Carried Forward)

^†While Activella 0.5mg/0.1mg was not directly studied in these trials, the US trial showed that addition of NETA to estradiol enhances the effect on BMD, therefore the BMD changes expected from treatment with Activella 0.5mg/0.1mg should be at least as great as observed with estradiol 0.5mg.

Effect on Bone Turnover

Activella 1.0 mg/0.5 mg reduced serum and urine markers of bone turnover with a marked decrease in bone resorption markers (e.g., urinary pyridinoline crosslinks Type 1 collagen C-telopeptide, pyridinoline, deoxypyridinoline) and to a lesser extent in bone formation markers (e.g., serum osteocalcin, bone-specific alkaline phosphatase, C-terminal propetide of type 1 collagen). The suppression of bone turnover markers was evident by 3 months and persisted throughout the 24-month treatment period.

Treatment with 0.5 mg estradiol decreased biochemical markers of bone resorption (urinary pyridinoline, urinary deoxypyridinoline) and bone formation (bone-specific alkaline phosphatase) compared to placebo. These decreases occurred by 6 months of treatment after which the levels were maintained throughout the 24 months.

Women's Health Initiative Studies

The WHI enrolled a total of 27,000 predominantly healthy postmenopausal women in two substudies to assess the risks and benefits of either the use of oral conjugated estrogens (CE 0.625 mg per day) alone or the use of oral conjugated estrogens (CE 0.625 mg) plus medroxyprogesterone acetate (MPA 2.5 mg per day) compared to placebo in the prevention of certain chronic diseases. The primary endpoint was the incidence of coronary heart disease (CHD) (nonfatal myocardial infarction (MI), silent MI and CHD death), with invasive breast cancer as the primary adverse outcome studied. A "global index" included the earliest occurrence of CHD, invasive breast cancer, stroke, pulmonary embolism (PE), endometrial cancer, colorectal cancer, hip fracture, or death due to other cause. The study did not evaluate the effects of CE or CE/MPA on menopausal symptoms.

The estrogen-plus-progestin substudy was stopped early. According to the predefined stopping rule, after an average follow-up of 5.2 years of treatment, the increased risk of breast cancer and cardiovascular events exceeded the specified benefits included in the "global index." The absolute excess risk of events included in the "global index" was 19 per 10,000 women-years (RR 1.15, 95% nCI 1.03-1.28).

For those outcomes included in the WHI "global index," that reached statistical significance after 5.6 years of follow-up, the absolute excess risks per 10,000 women-years in the group treated with CE/MPA were six more CHD events, seven more strokes, ten more PEs, and eight more invasive breast cancers, while the absolute risk reductions per 10,000 women-years were seven fewer colorectal cancers and five fewer hip fractures. (See BOXED WARNINGS, WARNINGS, and PRECAUTIONS.)

Results of the estrogen-plus-progestin substudy, which included 16,608 women (average age of 63 years, range 50 to 79; 83.9% White, 6.8% Black, 5.4% Hispanic, 3.9% Other) are presented in Table 4 below:

TABLE 4: RELATIVE AND ABSOLUTE RISK SEEN IN THE ESTROGEN-PLUS-PROGESTIN SUBSTUDY OF WHI AT AN AVERAGE OF 5.6 YEARS^a

Event	Relative Risk CE/MPA vs. Placebo (95% nCI b)	CE/MPA n = 8,506	Placebo n = 8,102
		Absolute Risk per 10,000 Women-years
CHD events	1.24 (1.00-1.54)	39	33
Non-fatal MI	1.28 (1.00-1.63)	31	25
CHD death	1.10 (0.70-1.75)	8	8
All strokes	1.31 (1.02-1.68)	31	24
Ischemic stroke	1.44 (1.09-1.90)	26	18
Deep vein thrombosis	1.95 (1.43-2.67)	26	13
Pulmonary embolism	2.13 (1.45-3.11)	18	8
Invasive breast cancerc	1.24 (1.01-1.54)	41	33
Invasive colorectal cancer	0.56 (0.38-0.81)	9	16
Endometrial cancer	0.81 (0.48-1.36)	6	7
Cervical cancer	1.44 (0.47-4.42)	2	1
Hip fracture	0.67 (0.47-0.96)	11	16
Vertebral fractures	0.65 (0.46-0.92)	11	17
Lower arm/wrist fractures	0.71 (0.59-0.85)	44	62
Total fractures	0.76 (0.69-0.83)	152	199
aResults are based on centrally adjudicated data. Mortality data was not part of the adjudicated data; however, data at 5.2 years of follow-up showed no difference between the groups in terms of all-cause mortality (RR 0.98, 95% nCI 0.82-1.18). bNominal confidence intervals unadjusted for multiple looks and multiple comparisons. cIncludes metastatic and non-metastatic breast cancer, with the exception of in situ breast cancer.

The estrogen-alone substudy was also stopped early because an increased risk of stroke was observed, and it was deemed that no further information would be obtained regarding the risks and benefits of estrogen alone in predetermined primary endpoints. Results of the estrogen-alone substudy, which included 10,739 women (average age of 63 years, range 50 to 79; 75.3% White, 15.1% Black, 6.1% Hispanic, 3.6% Other), after an average follow-up of 6.8 years are presented in Table 5 below.

TABLE 5: RELATIVE AND ABSOLUTE RISK SEEN IN THE ESTROGEN-ALONE SUBSTUDY OF WHI^a

Event	Relative Risk CE vs. Placebo (95% nCIa)	CE n = 5,310	Placebo n = 5,429
		Absolute Risk per 10,000 Women-years
CHD eventsb	0.95 (0.79-1.16)	53	56
Non-fatal MIb	0.91 (0.73-1.14)	40	43
CHD deathb	1.01(0.71-1.43)	16	16
Strokec	1.39 (1.10-1.77)	44	32
Deep vein thrombosisb,d	1.47 (1.06-2.06)	23	15
Pulmonary embolismb	1.37 (0.90-2.07)	14	10
Invasive breast cancerb	0.80 (0.62-1.04)	28	34
Colorectal cancerc	1.08 (0.75-1.55)	17	16
Hip fracturec	0.61 (0.41-0.91)	11	17
Vertebral fracturesc,d	0.62 (0.42-0.93)	11	17
Total fracturesc,d	0.70 (0.63-0.79)	139	195
Death due to other causesc,e	1.08 (0.88-1.32)	53	50
Overall mortalityc,d	1.04 (0.88-1.22)	81	78
Global Indexc,f	1.01 (0.91-1.12)	192	190
aNominal confidence intervals unadjusted for multiple looks and multiple comparisons. bResults are based on centrally adjudicated data for an average follow-up of 7.1 years. cResults are based on an average follow-up of 6.8 years. dNot included in Global Index. eAll deaths, except from breast or colorectal cancer, definite/probable CHD, PE or cerebrovascular disease. fA subset of the events was combined in a "global index," defined as the earliest occurrence of CHD events, invasive breast cancer, stroke, pulmonary embolism, colorectal cancer, hip fracture, or death due to other causes.

For those outcomes included in the WHI "global index" that reached statistical significance, the absolute excess risk per 10,000 women-years in the group treated with estrogen-alone was 12 more strokes, while the absolute risk reduction per 10,000 women-years was six fewer hip fractures. The absolute excess risk of events included in the "global index" was a nonsignificant two events per 10,000 women-years. There was no difference between the groups in terms of all-cause mortality. (See BOXED WARNINGS, WARNINGS, and PRECAUTIONS.)

Final adjudicated results for CHD events from the estrogen-alone substudy, after an average follow-up of 7.1 years, reported no overall difference for primary CHD events (nonfatal MI, silent MI and CHD death) in women receiving CE alone compared with placebo (see Table 5).

Women's Health Initiative Memory Study

The estrogen plus progestin Women's Health Initiative Memory Study (WHIMS) substudy of WHI enrolled 4,532 predominantly healthy postmenopausal women 65 years of age and older (47%, age 65 to 69 years, 35%, age 70 to 74 years, 18%, 75 years of age and older) to evaluate the effects of CE 0.625 mg plus MPA 2.5 mg daily on the incidence of probable dementia (primary outcome) compared with placebo.

After an average follow-up of four years, 40 women in the estrogen-plus-progestin group (45 per 10,000 women-years) and 21 in the placebo group (22 per 10,000 women-years) were diagnosed with probable dementia. The relative risk of probable dementia in the hormone therapy group was 2.05 (95% CI 1.21-3.48) compared to placebo. It is unknown whether these findings apply to younger postmenopausal women. (See BOXED WARNINGS, WARNINGS, Dementia, and PRECAUTIONS, Geriatric Use.)

The estrogen-alone WHIMS, a substudy of the WHI study, enrolled 2,947 predominantly healthy postmenopausal women 65 years of age and older (45%, age 65 to 69 years, 36%, age 70 to 74 years, 19%, 75 years of age and older) to evaluate the effects of conjugated estrogens (CE 0.625 mg) on the incidence of probable dementia (primary outcome) compared with placebo.

After an average follow-up of 5.2 years, 28 women in the estrogen-alone group (37 per 10,000 women-years) and 19 in the placebo group (25 per 10,000 women-years) were diagnosed with probable dementia. The relative risk of probable dementia in the estrogen-alone group was 1.49 (95% CI 0.83-2.66) compared to placebo.

When data from the two populations were pooled as planned in the WHIMS protocol, the reported overall relative risk for probable dementia was 1.76 (95% CI 1.19-2.60). Differences between groups became apparent in the first year of treatment. It is unknown whether these findings apply to younger postmenopausal women. (See BOXED WARNINGS, WARNINGS, Dementia, and PRECAUTIONS, Geriatric Use.)

Last updated on RxList: 9/29/2008

Physicians are advised to discuss the contents of the Patient Information leaflet with patients for whom they prescribe Activella 1.0 mg/0.5 mg or Activella 0.5 mg/0.1 mg.

Last updated on RxList: 9/29/2008

IMPORTANT NOTE: This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your health care professional. Always seek the advice of your health care professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your health care professional. This information does not contain any assurances that this product is safe, effective, or appropriate for you.

ESTRADIOL/NORETHINDRONE - ORAL

(ES-tra-DYE-ol/nor-ETH-in-drone)

COMMON BRAND NAME(S): Activella

WARNING: Rarely, very serious side effects have occurred when estrogen-only and combination hormone replacement therapies (estrogen and progestin HRT) are used after menopause. Discuss the risks and benefits of hormone treatment and your personal health history with your doctor.

Combination HRT should not be used to prevent heart disease or dementia. Combination HRT can rarely cause heart disease (e.g., heart attacks), stroke, serious blood clots (pulmonary embolism and deep venous thrombosis), dementia, and breast cancer. The risk for stroke and breast cancer increases with age, especially for women older than 75. Estrogens may also increase the risk of cancer of the ovaries. Some of these risks appear to depend on the length of time this drug is used and the amount of estrogen per dose. Therefore, this medication should be used for the shortest possible length of time at the lowest effective dose, so you can obtain the benefits and minimize the chance of serious side effects from long-term treatment. Discuss the details with your doctor and check with him/her regularly (e.g., every 3-6 months) to see if you still need to take this medication.

If you use this drug for an extended time, you should have a complete physical exam at regular intervals (e.g., once a year) or as directed by your doctor. See Notes section.

USES: This medicine comes with a Patient Information Leaflet. Read it carefully. Ask your doctor, nurse, or pharmacist any questions that you may have about this medicine.

This medication is used to reduce menopause symptoms. It helps reduce episodes of flushing and sweating of the upper body and face, commonly called hot flashes. It also helps treat dryness, itching, and burning around the vagina. These symptoms occur when a woman's body no longer makes the usual amount of female hormone (estrogen). This medication is a combination of 2 female hormones: an estrogen (estradiol) and a progestin (norethindrone). A progestin is added to estrogen replacement therapy to reduce the risk of cancer of the uterus. A woman who has had her uterus removed does not need progestin and should not be treated with this combination medication.

If you need treatment only for vaginal menopause symptoms, products applied directly inside the vagina should be considered before medications that are taken by mouth, absorbed through the skin, or injected.

This medication may also be used to prevent bone loss (osteoporosis) in people at high risk who cannot take other drugs that are safe and effective to prevent or treat bone loss (e.g., raloxifene, bisphosphonates such as alendronate). These medicines should be considered for use before estrogen/progestin HRT therapy for osteoporosis.

HOW TO USE: Read the Patient Information Leaflet provided by your pharmacist before you start using this medication and each time you get a refill. If you have any questions, consult your doctor or pharmacist.

Take this medication by mouth, usually once daily or as directed by your doctor. Take this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Inform your doctor if your condition does not improve or if it worsens.

SIDE EFFECTS: Dizziness, lightheadedness, headache, stomach upset, bloating, irritability, changes in sleep patterns, nausea, weight changes, increased/decreased interest in sex, change in vaginal discharge, or breast tenderness may occur. If any of these persist or worsen, tell your doctor promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these unlikely but serious side effects occur: mental/mood changes (e.g., depression, memory loss), breast lumps, nipple discharge, swelling of the hands/feet, unusual vaginal bleeding (e.g., spotting, breakthrough bleeding, prolonged/returning bleeding), yellowing eyes/skin, stomach/abdominal pain, worsening of seizures, signs of worsening diabetes control (e.g., increased thirst and urination).

This medication may rarely cause very serious problems such as heart attacks, stroke, and blood clots. Seek immediate medical attention if you experience any of the following: chest/jaw/left arm pain, sudden severe headache, weakness on one side of the body, confusion, slurred speech, sudden vision changes (e.g., double vision, loss of vision), pain/redness/swelling/weakness of the arms/legs, calf pain/swelling that is warm to the touch, trouble breathing, coughing up blood, sudden dizziness/fainting.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching, swelling, severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Contact your doctor for medical advice about side effects. The following numbers do not provide medical advice, but in the US you may report side effects to the Food and Drug Administration (FDA) at 1-800-FDA-1088. In Canada, you may call Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: vaginal bleeding of unknown cause, certain types of cancer (breast, ovary, uterus), blood clots, recent stroke or heart attack (within 1 year), liver disease.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: family medical history (including blood clots, breast lumps/cancer), asthma, diabetes, seizures, migraine headaches, heart disease (e.g., high blood pressure, heart attacks, congestive heart failure), past strokes, kidney disease, underactive thyroid (hypothyroidism), abnormal calcium level in the blood, mental/mood disorders (e.g., depression, memory loss), high blood pressure during pregnancy (toxemia), yellowing eyes/skin (cholestatic jaundice) during pregnancy or with past estrogen use, uterus problems (e.g., uterine fibroids, endometriosis), high blood cholesterol/fat (triglyceride) levels, gallbladder disease, obesity, certain blood disorder (porphyria), lupus.

This drug may make you dizzy or lightheaded. Use caution while driving, using machinery, or doing any activity that requires alertness. Limit alcoholic beverages.

If you are nearsighted or wear contact lenses, you may develop vision problems or trouble wearing your contact lenses. Consult your eye doctor if these problems occur.

This drug may cause a patchy darkening of the skin on the face (melasma). Sunlight may worsen this darkening. Avoid prolonged sun exposure, tanning booths, and sunlamps. Use a sunscreen and wear protective clothing when outdoors.

Do not smoke cigarettes or use tobacco. Smoking/using tobacco while taking this medication further increase your risk for stroke, blood clots, high blood pressure, and heart attacks, especially in women older than 35.

If you will be having surgery or will be confined to a chair or bed for a long time (e.g., a long plane flight), notify your doctor beforehand. Special precautions may need to be taken in these circumstances while you are taking this drug because of the increased risk for blood clots.

This medication must not be used during pregnancy. If you become pregnant or think you may be pregnant, tell your doctor immediately.

This medication is not effective for preventing a miscarriage and should not be used for this purpose.

Small amounts of this medication pass into breast milk. This drug may reduce the quality and amount of breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

This drug should not be used with the following medications because very serious interactions may occur: anastrozole, exemestane.

If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting estradiol/norethindrone.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription products you may use, especially of: corticosteroids (e.g., prednisone), raloxifene, tamoxifen, warfarin, drugs affecting liver enzymes that remove estrogens from your body (such as azole antifungals including itraconazole, macrolide antibiotics including erythromycin, rifamycins including rifabutin, St. John's wort, certain anti-seizure medications including carbamazepine, phenobarbital, phenytoin).

This product can affect the results of certain lab tests. Make sure laboratory personnel and all your doctors know you use this drug.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

OVERDOSE: If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe nausea/vomiting, unusual vaginal bleeding in females.

NOTES: Do not share this medication with others. Keep all medical and laboratory appointments. You should have a complete physical examination that includes blood pressure measurements and breast/pelvic examinations at regular intervals (e.g., once a year) or as directed by your doctor. Follow your doctor's instructions on how to examine your own breasts and report any lumps immediately. You should also be regularly screened for cervical cancer (e.g., Pap test) and have periodic mammograms as determined by your doctor. Consult your doctor for more details.

Lifestyle changes that help promote healthy bones include increasing weight-bearing exercise, stopping smoking, limiting alcohol, and eating well-balanced meals that contain adequate calcium and vitamin D. Since you may also need to take calcium and vitamin D supplements and make lifestyle changes, consult your doctor for specific advice.

Additional lifestyle changes (e.g., reducing stress, eating a low fat/low salt diet, losing weight if you are overweight) to control or prevent high blood pressure, high cholesterol, and diabetes help to prevent heart disease and strokes. Keep your mind active with mental exercises to help prevent dementia. Discuss with your doctor lifestyle changes that might benefit you.

You can also manage hot flashes by keeping a cool body temperature (e.g., using a fan, drinking cool beverages, dressing lightly/in layers, avoiding hot/spicy foods). Limiting caffeine and alcohol, exercising regularly, and learning relaxation techniques may help reduce hot flashes. Vaginal lubricants can help lessen discomfort during intercourse.

MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE: Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised July 2008 Copyright(c) 2008 First DataBank, Inc.