17 beta-estradiol and norethisterone acetate in low doses as continuous combined hormone replacement therapy.

OBJECTIVES: To evaluate low doses of 17 beta-estradiol (E2) and norethisterone acetate (NETA) as continuous combined hormone replacement therapy (HRT) in their effects on vasomotor symptoms, bleeding episodes, endometrial histology and mastalgia. METHOD: Sixty postmenopausal women were randomly allocated to three treatment groups and were given 1 mg E2 and 0.25 mg NETA (A), 1 mg E2 and 0.5 mg NETA (B) and 2 mg E2 and 1.0 mg NETA (C) in daily doses. The treatment period was 1 year. RESULTS: A similar statistically significant reduction of climacteric symptoms (P < 0.05) was found in all groups. Bleedings, mainly as spottings, occurred most commonly during the first treatment months. Fewer bleeding episodes and a higher percentage of amenorrhea was noted in group B compared to the other groups but did not reach statistical significance. All endometrial biopsies showed atrophy. Women in group A and B had less severe mastalgia (P < 0.05) compared to group C, given higher doses of steroids. CONCLUSION: Postmenopausal women taking 1 mg of E2 plus 0.5 mg NETA as continuous combined HRT reported a marked reduction of climacteric complaints and good bleeding control. No endometrial proliferation was detected after 1 year of treatment. This type of therapy may be beneficial especially for elderly women, in whom bleeding may be annoying.

Comparison of the gonadotropin-releasing hormone agonist goserelin acetate alone versus goserelin combined with estrogen-progestogen add-back therapy in the treatment of endometriosis.

OBJECTIVE: To investigate whether the addition of low-dose estrogen-P combination hormone replacement therapy (HRT) to GnRH agonist (GnRH-a) treatment for endometriosis reduces the pharmacologic side effects of such treatment without reducing efficacy and to determine the endocrinologic changes during treatment. DESIGN: Prospective, randomized, double-blind, placebo-controlled, comparative study of two drug regimens: 3.6 mg goserelin acetate in a 28-day SC depot formulation once monthly for 6 months plus either a combination of 2 mg 17 beta-E2 and 1 mg norethisterone acetate (NET) 1 mg or matching placebo tablets once daily for 6 months. SETTING: Multicenter study in three tertiary referral centers at university teaching hospitals and two central hospitals. PATIENTS: Women with laparoscopically confirmed symptomatic endometriosis were included in the study. RESULTS: Of the total of 109 patients screened, 93 were recruited and 88 patients were randomized to either the HRT or the placebo group. Four women were withdrawn because of various medical reasons, and 76 patients were followed-up for a total of 12 months. In terms of efficacy, there was no difference between the two drug regimens for objective or subjective response. There were significantly less postmenopausal symptoms in the patients treated with goserelin plus HRT compared with those treated with goserelin plus placebo. CONCLUSION: Goserelin diminished significantly the symptoms and laparoscopic scores of endometriosis. The addition of HRT did not reduce the efficacy of goserelin but diminished the postmenopausal symptoms during treatment.

Norethindrone--a review of therapeutic applications.

Norethindrone is utilized for numerous noncontraceptive therapies, especially during the menopause. Through an analysis of the literature we have described the pharmacological profile of norethindrone and the potential therapeutic implications of low-dose therapies, with an emphasis on endometrial pathology, climacteric symptoms, lipid metabolism, and bone density.

A multicentred phase III comparative clinical trial of Mesigyna, Cyclofem and Injectable No. 1 given monthly by intramuscular injection to Chinese women. I. Contraceptive efficacy and sid effects.

A phase III clinical study was carried out among 5680 fertile Chinese women to evaluate efficacy and side effects of three monthly injectable contraceptives: Mesigyna, Cyclofem and Chinese Injectable No. 1. When used in a once-a-month treatment schedule (part 1 of study), the effectiveness of Chinese Injectable No. 1 was unacceptably low; 36 pregnancies occurred during the first 1743 women-months of use, 16 before the second injection. The study was restarted with a revised injection schedule for Injectable No. 1: two injections separated by 9 +/- 1 days during the first month and subsequent injections given 10-12 days after the onset of bleeding, or if no bleeding occurred, 28 days after previous injection. In part 2 of the study, 988, 990 and 992 subjects were provided Mesigyna, Cyclofem and Injectable No. 1, respectively. Life-table pregnancy rates at one year were 0.41%, 0% and 0.77% (p < 0.05), respectively; the overall discontinuation rates at one year were 13.9%, 19.1% and 20.4% (p < 0.001). Discontinuation rates for bleeding problems were significantly different between the groups: discontinuation rates for amenorrhea were 0.58%, 3.71% and 0.68% (p < 0.001) for Mesigyna, Cyclofem and Injectable No. 1; for other bleeding problems, the rates were 4.88%, 8.38% and 12.64% (p < 0.001). There were no significant differences between the groups regarding discontinuation for other medical or non-medical reasons. Mean weight changes after one year of use were small: 0.73, 0.86 and 0.17 kg for the three groups, respectively. Both Mesigyna and Cyclofem were very effective for contraception, but Mesigyna appeared to be tolerated slightly better with regard to cycle control; the modified dose regimen for Injectable No. 1 also gave a low pregnancy rate but was associated with higher rates of discontinuation.

A multicentred phase III comparative clinical trial of Mesigyna, Cyclofem and Injectable No. 1 given by intramuscular injection to Chinese women. II. The comparison of bleeding patterns.

Between 1988 and 1992, a randomized phase III clinical trial was conducted in China to compare three monthly injectable contraceptives: Mesigyna, Cyclofem and Injectable No. 1. This paper presents a detailed analysis of the menstrual diaries provided by 5098 (89%) of the subjects. In total, 902, 903 and 913 diaries were analyzed to compare bleeding patterns induced by Mesigyna, Cyclofem and Injectable No. 1. The first withdrawal bleeding usually occurs 14-20 days after the first injection for all three of these preparations. Thereafter, 50% of Mesigyna users had precisely 3 bleeding/spotting episodes every 90 days, 50% of Cyclofem users had 2-3 and 50% of Injectable No. 1 users had 3-4 episodes every 90 days. Relative to users of Mesigyna or Cyclofem, Injectable No. 1 users had 2-3 more bleeding/spotting days, and a shorter length of bleeding/spotting-free intervals in each period. 63.7%, 41.4% and 60.6% of subjects using Mesigyna, Cyclofem and Injectable No. 1, respectively, had bleeding patterns similar to their untreated patterns in the first 90-day period. The percentages increased to 82.2% 67.8% and 75.0% in the fourth 90-day period. A total of 1815 diaries for Mesigyna and 1802 for Cyclofem were analyzed for more in depth comparison of these two methods. The number of bleeding/spotting days over four periods showed little difference between the two group, but there were more spotting days and there was greater individual variability among Cyclofem users.(ABSTRACT TRUNCATED AT 250 WORDS)

PIP: Between October 1988 and July 1990, a randomized multicentered phase III clinical trial was conducted in three provinces of China to compare three monthly injectable contraceptives (Mesigyna [50 mg norethisterone enanthate + 5 mg estradiol valerate], Cyclofem [25 mg medroxyprogesterone acetate + 5 mg estradiol cypionate], and Injectable No.1 [250 mg 17-hydroxyprogesterone caproate + 5 mg estradiol valerate]). A detailed analysis of the menstrual diaries of 5098 women aged 18-35 years compared the vaginal bleeding patterns associated with the injectables. Women in all three groups experienced more bleeding/spotting (B/S) days, more bleeding episodes, shorter bleeding-free intervals, and larger variability during the first 90 days than during the following three 90-day periods (p 0.001). 90% of Cyclofem users had 1-4 B/S episodes. 90% of Mesigyna users had 2-4.2 B/S episodes. Cyclofem users had more spotting days than did Mesigyna users in each 90-day period (5-8 vs. 5-6). Acceptable bleeding patterns (i.e., bleeding patterns similar to untreated patterns) predominated, on the most part, in all four periods (63.7-82.2% for Mesigyna users, 41.4-67.8% for Cyclofem users, and 60.6-75% for Injectable No.1 users). Acceptability increased with each 90-day period for all three injectables. Acceptability of bleeding patterns was much higher among Mesigyna users than Cyclofem users (p 0.001). Prolonged bleeding, followed by irregular bleeding and frequent bleeding, were the most common bleeding disturbances. Irregular bleeding decreased with time. 79.1% of Mesigyna and Cyclofem users who finished the study had an acceptable pattern. 70.7% of women who stopped for non-bleeding reasons had an acceptable pattern compared to 31.3% of those who stopped for bleeding reasons. These findings show that Mesigyna users experienced better cycle control and more acceptable bleeding patterns than did the users of the other two injectables.

The acceptability of a combined oestrogen/progestogen contraceptive vaginal ring.

The acceptability of a vaginal ring releasing ethinyl oestradiol 20 mcg per day and norethindrone acetate 1 mg per day was assessed during a six-month phase II trial comparing three different regimens, which was carried out simultaneously in Los Angeles and Sydney. Sixty women were enrolled in Sydney and 90 in Los Angeles. On admission into the study, the women were asked to complete a questionnaire which gave details of age, last contraceptive method used, contraceptive methods used in the past and their reason for liking or disliking previous contraceptive methods, as well as their reason for stopping the last method. On completion of the study or leaving the study for any reason, each woman was asked to complete an acceptability questionnaire which included her experiences with the ring and the rating of the method. The responses to these two questionnaires form the basis of this report. The overall rating of the ring was similar in both the Sydney and Los Angeles groups. Sixty-nine percent of women rated the method as very good. Seventy-two percent of women in Los Angeles and 62% of women in Sydney liked the ring much more than their most liked previous method. In both groups the method they liked best apart from the ring was the pill (62% in Sydney and 53% in Los Angeles). The major reasons for liking the ring were convenience of use, effectiveness and no requirements for taking medication daily. Most women in both studies would recommend the ring to others (92% in Sydney and 89% in Los Angeles).

A contraceptive vaginal ring releasing norethindrone acetate and ethinyl estradiol.

A core design contraceptive vaginal ring (CVR) releasing 650 mcg of norethindrone acetate (NA) and 10, 20, 30 or 65 mcg of ethinyl estradiol (EE) daily was developed and tested in 99 women. The CVR inhibited ovulation well with 30 or 65 mcg EE. Vaginal bleeding was better controlled than in 23 control women using NA/EE oral contraceptives. Side effects were comparable to controls for the 20 and 30 mcg EE CVR. The 65 mcg EE CVR resulted in an unacceptably high level of nausea. The 20 and 30 mcg EE CVR caused an increase in serum HDL cholesterol and triglycerides. Total cholesterol was unchanged. Angiotensinogen and sex hormone binding globulin-binding capacity were increased in a subgroup of the 20 and 30 mcg EE CVR subjects, similar to that of 20 controls using EE/gestodene oral contraceptives. This new CVR offers an excellent contraceptive alternative with the best performance provided by the 30 mcg EE dose.

Dose-finding study of a contraceptive ring releasing norethindrone acetate/ethinyl estradiol.

A core design contraceptive vaginal ring (CVR) with average daily release of 650 mcg of norethindrone acetate (NA) and 30 mcg of ethinyl estradiol (EE) inhibited ovulation and controlled vaginal bleeding well, but caused some nausea. This study was designed to minimally alter the dose of steroid to see if nausea could be reduced without loss of contraceptive efficacy. This 30/650 CVR was compared to a CVR releasing 20 mcg of EE and 1000 mcg of NA (20/1000) and another releasing 25 mcg of EE and 650 mcg of NA (25/650) in 69 subjects. Twenty-three subjects using an oral contraceptive containing NA/EE served as controls. Ovulation inhibition was excellent and comparable to the OC for all formulations. The CVR provided better control of vaginal bleeding than did the OC. Side effects were equivalent to the OC with the exception of a slight increase in nausea in CVR users. Lipid changes and globulin increases were comparable to oral contraceptive users. The 20/1000 CVR increased sex hormone binding globulin-binding capacity less than the other two CVRs. The performance of the three CVRs was not significantly different, but the 25/650 showed a trend of reduced performance relative to the other two formulations.

A multicentred, two-year, phase III clinical trial of norethisterone enanthate 50 mg plus estradiol valerate 5 mg as a monthly injectable contraceptive.

Norethisterone enanthate (NET-EN) 50 mg combined with estradiol valerate (EV) 5 mg was studied as a once-a-month injectable contraceptive with regard to effectiveness, cycle control, adverse events and acceptability. In eight Family Planning Centres from 5 Latin American countries, 652 fertile women were followed-up for a period of 24 months, providing a total of 10,689 woman-months of experience. Only 1 pregnancy occurred, in the first treated month a few days before the second injection (failure rate 0.11 per 100 woman-years). Under treatment, the first cycle was drastically shortened in most cases, but thereafter cycles tended to recover to pre-treatment patterns. There was a significant decrease of hypermenorrhea and dysmenorrheic cycles. Intracyclic bleeding and spotting appeared in 1.2% and 2.4%, respectively, and amenorrhea in 2.5% of cycles. Incidence of other adverse events was very low with the exception of weight gain of 2 Kg (28%). Continuation rate at 12 months was 64.7%. The cumulative discontinuation rate due to bleeding problems was 7.4% and 10.7% due to adverse events at 24 months.

Effect of long-acting progestagen-only injectable contraceptives on carbohydrate metabolism and its hormonal profile.

Two groups, each composed of 20 women, who used depomedroxyprogesterone acetate (DMPA) or norethisterone enanthate (NET-EN) injectable contraceptives were investigated for changes in 75-g OGTT and in the fasting and two-hour post oral glucose load (2-hours) levels of serum insulin, growth hormone, glucagon, cortisol and blood pyruvate. Samples were taken before and 3, 6 and 12 months after use of injectables. DMPA and NET-EN caused significant changes in mean blood glucose and pyruvate and in mean serum insulin, growth hormone and glucagon, but not in mean fasting cortisol. Changes with NET-EN started after 3 months, became maximal after 6 months and reverted to normal after 12 months of use, due to more frequent administration during the first 6 months of use (every 60 +/- 5 days) and to more spacing of the injections (every 84 +/- 5 days) after that. Changes with DMPA started after 3 months, and increased with the duration of use to become maximal after 12 months. Maximal changes were similar with DMPA and NET-EN and consisted of: a significant increase in fasting blood glucose and pyruvate and serum insulin; a significant increase in 2-hour blood glucose and pyruvate, serum insulin, growth hormone and glucagon. Although significant changes in blood glucose levels occurred with both DMPA and NET-EN, yet they did not reach the lower cut-off levels for impaired glucose tolerance in any user. With the same spacing of injections, i.e. every 84 +/- 5 days for NET-EN and every 90 +/- 5 days for DMPA, the effects on various parameters studied were less with NET-EN.

Acceptability of injectable contraceptives in Assiut, Egypt.

The present work was a randomized comparative study of two injectable progestogen-only contraceptives. The first group (200 subjects) received 150 mg of depotmedroxyprogesterone acetate (Depoprovera) every 84 +/- 7 days and the second (200 subjects) received 200 mg of norethisterone enanthate (Noristerat) every 56 +/- 7 days. Acceptors of injectable contraceptives in Assiut, Egypt, were mainly women looking for fertility termination. Menstrual disruption was the main side effect among both treatment groups. Amenorrhoea was the commonest menstrual complaint and was the main reason for discontinuation in both groups. Only one pregnancy occurred during NET-EN use; two more pregnancies occurred, one in each of the two groups but there were indications that conception preceded the first injection. Menstrual irregularities were generally more frequent with DMPA users. However, DMPA had better one-year continuation rates than NET-EN (68.8 +/- 3.5 and 57.1 +/- 3.6 per 100 women, respectively).

Assessment of a new low-dose once-a-month injectable contraceptive.

Norethisterone (NET) in combination with mestranol (ME), in a macrocrystalline aqueous suspension that provides sustained release of steroids, was assessed as a once-a-month injectable contraceptive in ten healthy women of reproductive age. The ovarian function was studied before and after the intramuscular administration of 12mg NET plus 1.2mg ME, delivered as crystals of 150 micron average size. Serial blood samples were taken throughout the injection intervals in all women to measure serum progesterone (P), estradiol (E2), and NET. The NET/ME preparation effectively inhibited ovulation in 23 out of the 25 injection intervals studied. The administration of this formulation induced in some women a small degree of follicular maturation not followed by luteal activity. The endometrial bleeding patterns after each injection showed a bleeding-free period of two to three weeks. The overall data demonstrate that the parenteral administration of a macrocrystalline steroid preparation of NET/ME can bring about a sustained release contraceptive system at a substantially lower dose than those currently employed in once-a-month injectable contraception.