B. Düsterberg

A twelve-month comparative clinical investigation of two low-dose oral contraceptives containing 20 μg ethinylestradiol/75 μg gestodene and 30 μg ethinylestradiol/75 μg gestodene, with respect to efficacy, cycle control, and tolerance

The aim of this study was to compare contraceptive reliability, cycle control, and tolerance of an oral contraceptive containing 20 micrograms ethinylestradiol (EE2) and 75 micrograms gestodene (GSD), with a reference preparation containing a similar dose of gestodene but in combination with 30 micrograms ethinylestradiol. A higher incidence of intermenstrual bleeding was apparent under the 20 micrograms EE2 oral contraceptive. For the 20 micrograms EE2 preparation, 47.4% of all women reported spotting at least once over a period of 12 treatment cycles, whereas this figure was 35.5% for the 30 micrograms EE2 pill (p < 0.05). However, the incidence was within a range that corresponds to that of other OCs. The cumulative breakthrough bleeding rates (at least once during the one year of treatment) of 14.5% (20 micrograms EE2) and 11.8% (30 micrograms EE2) of women were not significantly different. In relation to all cycles, the intermenstrual bleeding rates were remarkably lower, indicating that the majority of the volunteers experienced such events only in few cycles under treatment: the spotting rate was 11.5% (20 micrograms EE2) and 7.2% (30 micrograms EE2) of all cycles, and the breakthrough bleeding rate was 2.6% and 1.6% of all cycles, respectively. Three pregnancies were recorded during the study (one in the 20 micrograms EE2 + 75 micrograms GSD group, two in the 30 micrograms EE2 + 75 micrograms GSD group). All three could be explained either by intake irregularities or by circumstances impairing the contraceptive effect. The influence of both treatments on the blood pressure and body weight proved to be extremely slight. Adverse events in both groups were rare and differences in the frequency of adverse events were not apparent. The discontinuation rate due to adverse events, including intermenstrual bleeding, was low (9.8% for 20 micrograms EE2 + 75 micrograms GSD, and 7.2% for 30 micrograms EE2 + 75 micrograms GSD) and was in the lower range known for other oral contraceptives. Both preparations were well accepted by the volunteers. The data obtained demonstrate clinically acceptable cycle control, good tolerance, and a high standard of contraceptive reliability for both drugs. Prescription of the 20 micrograms EE2 preparation could be the first-line therapy in order to provide the lowest amount of EE2 possible. In case of persistent cycle control problems, a switch to the 30 micrograms EE2 drug should be considered.

A comparative study of the effects of the hemostatic system of two monophasic gestodene oral contraceptives containing 20 μg and 30 μg ethinylestradiol

The effects of two oral contraceptives, containing gestodene and either 20 micrograms or 30 micrograms ethinylestradiol, on hemostatic parameters was investigated in a six-month randomized study involving a total of 40 healthy women between the ages of 18 and 30 years. A large number of hemostatic parameters were measured, which were categorized as either pro-coagulatory, anti-coagulatory, profibrinolytic, anti-fibrinolytic or indicative of fibrin turnover. Additionally, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) were measured before and after venous occlusion and delta and ratio values calculated. Pro-coagulatory factors as well as reaction products reflecting in vivo coagulatory activity (thrombin-antithrombin III complex, prothrombin fragment 1 + 2) were found to increase. Among the anti-coagulatory parameters, only protein S concentration and protein S activity decreased, most notably in the 30 micrograms EE group. There was a corresponding increase in fibrinolytic activity reflected by reaction products of in vivo fibrinolysis (plasmin-antiplasmin 2-complex, fibrin-degradation products). Measurement of t-PA and PAI-1, before and after venous occlusion, revealed that the fibrinolytic response was more pronounced in the 20 micrograms EE group. There was also an increase in the threshold of fibrinolytic inhibition (ratio PAI-1) in both groups, which was less pronounced in the 20 micrograms EE group. Apart from isolated measurements, all parameters remained within their normal ranges and values returned to baseline in the follow-up cycle. It is concluded that both preparations had a balanced effect on the hemostatic system stimulating both pro-coagulant and fibrinolytic activity. No statistically significant differences were observed between the two groups; however, there was a trend towards greater fibrinolytic capacity in the 20 micrograms EE group.

Comparison of Efficacy, Cycle Control, and Tolerability of Two Low-dose Oral Contraceptives in a Multicenter Clinical Study

This study compares the contraceptive reliability, cycle control, and tolerability of two oral contraceptive preparations containing 20 micrograms of ethinyl estradiol combined with either 75 micrograms of gestodene (EE/GSD) or 150 micrograms of desogestrel (EE/DSG). Women received the trial preparations daily for 21 days, followed by a 7-day pill-free interval. Contraceptive efficacy, cycle control, and tolerability were evaluated over a period of 12 cycles. Efficacy data of 14,700 treatment cycles (EE/GSD: 7299; EE/DSG: 7401) were obtained from 1476 women (EE/GSD, n = 740; EE/DSG, n = 736). Both preparations provided effective contraception and good cycle control with a similarly low incidence of both spotting and breakthrough bleeding. The spotting rates in both treatment groups decreased from 35.1% (EE/GSD) and 37.5% (EE/DSG) in the first treatment cycle to approximately 10% in the fourth treatment cycle. The spotting incidence as percent of the total number of cycles was 12.7% for EE/GSD and 14.3% for EE/DSG. The breakthrough bleeding incidence was 5.2% of all cycles for EE/GSD and 6.0% of all cycles for EE/DSG. For 84.7% of the cycles in the gestodene group and for 82.5% of the cycles in the desogestrel group, neither spotting nor breakthrough bleeding were recorded. Overall, the spotting and breakthrough bleeding incidence tended to be lower with EE/GSD than with EE/DSG. However, the difference was not statistically significant. Amenorrhea was recorded in 2.7% of the cycles with EE/GSD and in 2.9% with EE/DSG. Both preparations were well tolerated and showed a similar pattern of adverse events. More than 83% of the women in both groups either did not gain weight or lost more than 2 kg. Both preparations had a beneficial effect on dysmenorrhea. Both regimens provided reliable contraception and good cycle control. The incidence of adverse events was relatively low and both preparations were well tolerated.

A three-year clinical investigation into efficacy, cycle control and tolerability of a new low-dose monophasic oral contraceptive containing gestodene

This long-term, open-label multicenter study investigated the clinical efficacy and tolerability of a monophasic oral contraceptive containing 20 micrograms ethinylestradiol and 75 micrograms gestodene. A total of 670 women between the ages of 18 and 45 years received the trial preparation over a 3-year period, giving 19,095 evaluable cycles. Of the 670 participants in the study, 75% completed at least 24 cycles with the trial preparation and 46% remained in the study for the full 3 years. One pregnancy occurred during the study which was considered by the investigator to be the result of misuse of the drug, giving an uncorrected Pearl Index of 0.07. Cycle control with the trial preparation was good, especially in women who did not miss any pills. By cycle 3, only 10.2% of women who had not missed pills reported intermenstrual bleeding (scanty or medium/excessive bleeding) and this decreased to 2.3% by cycle 36. The preparation was well tolerated, with a low incidence of unprompted adverse events. There were no clinically significant changes in mean body weight or blood pressure. Over the 3 years of the study, 10% of women withdrew from the study for reasons related mostly to mild adverse events. Results from this study demonstrate that the trial preparation is a reliable and well-tolerated oral contraceptive that provides good cycle control.

An open label, comparative study of the effects of a dose-reduced oral contraceptive containing 20 μg ethinyl estradiol and 100 μg levonorgestrel on hemostatic, lipids, and carbohydrate metabolism variables

In this open label, randomized study we compared the influence of a dose-reduced oral contraceptive containing 20 microg ethinyl estradiol (EE) and 100 microg levonorgestrel (20 EE) with a reference preparation containing 30 microg EE and 150 microg levonorgestrel (30 EE) on hemostatic, lipids, and carbohydrate metabolism variables. Data from 48 volunteers were obtained. The direction of the change (increase or decrease) in most of the hemostatic variables were similar in both treatment groups. In particular, prothrombin fragment 1 + 2 increased during treatment, reaching a median percent change of 40% in the 20 EE group and of 17% in the 30 EE group after one year. D-Dimer fibrin split products remained virtually unchanged, with no change at Cycle 13. The median HDL2 cholesterol levels decreased by 26% in the 20 EE group and by 39.8% in 30 EE group (p = 0.0045 for group difference) after one year. The median one year change for LDL cholesterol was 3.23% in the 20 EE group, compared to 25% in the 30 EE group, for VLDL 11.1% compared to 38.8%, respectively, and for total triglycerides 10.0% compared to 37.5%, respectively. The median absolute change for the area under the curve (AUC)(0-3h) for glucose at treatment Cycle 13 was 41.25 mmol/L x min in the 20 EE group and 73.50 mmol/L x min in the 30 EE group. The AUC(0-3h) insulin at treatment Cycle 13 decreased in the 20 EE group by 1635.0 pmolL x min and increased in the 30 EE group by 11797.5 pmolL x min (p = 0.0491 for group difference). Both study treatments were safe and well tolerated by the volunteers. In conclusion, the balanced one-third dose reduction in this new oral contraceptive evoked similar effects on the hemostatic variables, but favorable results for the lipid and carbohydrate profiles.

A meta-analysis on the correlation between ovarian activity and the incidence of intermenstrual bleeding during low-dose oral contraceptive use.

We aimed to evaluate potential correlation between ovarian activity during use of combined oral contraceptives and the incidence of intermenstrual bleeding. Data from seven prospective clinical studies with five different combined low-dose oral contraceptives were retrospectively analyzed to determine ovarian activity measured by the Hoogland Score (follicle diameter and endogenous hormone levels) and cycle control. A total of 227 young fertile women were evaluated over three treatment cycles each. Women with intermenstrual bleeding had statistically significantly higher estradiol levels than those without intermenstrual bleeding. Also ,women with intermenstrual bleeding had significantly larger follicle-like structures than those without intermenstrual bleeding. For example ,in the second treatment cycle the difference of the mean follicle diameters between women without intermenstrual bleeding (12.5 mm) and women with spotting (16.9 mm) or breakthrough bleeding (16.1 mm) was statistically significant (p = 0.0179). Less than 17% of women with Hoogland Score 1 ,2 or 3 (low ovarian activity) reported intermenstrual bleeding. On the other hand ,35.2% of women with Hoogland Score 4 (active follicle-like structures) reported intermenstrual bleeding. The association between bleeding and Hoogland Score was statistically significant (p < 0.0011). The findings of this retrospective analysis provide evidence that high ovarian suppression is positively correlated with improved cycle control in terms of less frequent intermenstrual bleeding - slight and heavy.

Open, multicenter comparison of efficacy, cycle control, and tolerability of a 23-day oral contraceptive regimen with 20 μg ethinyl estradiol and 75 μg gestodene and a 21-day regimen with 20 μg ethinyl estradiol and 150 μg desogestrel

Abstract This prospective, open, randomized study was conducted to compare the contraceptive reliability, cycle control, and tolerability of a 23-day regimen with 20 μg ethinyl estradiol (EE) and 75 μg gestodene (GSD) and a 21-day regimen with 20 μg EE and 150 μg desogestrel (DSG). Participants took either 23 tablets with active substances plus 5 placebo tablets (23-day EE/GSD) or 21 tablets with active substances followed by 7 days without pill-taking (21-day EE/DSG). Contraceptive efficacy, cycle control, and tolerability were evaluated over a period of seven cycles. Efficacy data gathered from 5967 treatment cycles (23-day EE/GSD: 2975 cycles; 21-day EE/DSG: 2992 cycles) were obtained from 890 participants (445 in each group). Both preparations proved to be effective contraceptives and provided good cycle control. No pregnancy during treatment was recorded. This resulted in a study Pearl Index of 0.0 for both treatments. For 23-day EE/GSD, 32.4% of participants reported at least one intracyclic bleeding episode during Cycles 2–4 (primary target) compared to 31.5% for 21-day EE/DSG. In the 23-day EE/GSD group, intracyclic bleeding episodes were reported by 48.8% of the participants in Cycle 1 but in only 15.1% in Cycle 7, and in the 21-day regimen group by 43.4% in Cycle 1 and only 14.2% in Cycle 7. Overall, intracyclic bleeding was reported in 20.9% of cycles for both treatments. A greater number of 23-day EE/GSD participants had shorter withdrawal bleeding periods than with 21-day EE/DSG. In significantly (p Both preparations were well tolerated and showed a similar adverse events pattern. The discontinuation rate because of adverse events was low (23-day EE/GSD: 6.1%; 21-day EE/DSG: 5.6%). No serious vascular adverse events were reported. More than 82% in the 23-day EE/GSD group and 79% in the 21-day EE/DSG group either lost more than 2 kg of weight or did not gain weight during the study. The treatment effect on blood pressure was negligible. There were no appreciable changes in mean laboratory values over the course of the study compared to baseline.

Clinical acceptability of monophasic gestodene

The monophasic low-dose contraceptive containing 30 micrograms of ethinyl estradiol and 75 micrograms of gestodene has been tested in numerous clinical studies to determine contraceptive reliability, cycle control, and influence on metabolism and to uncover concomitant symptoms. Clinical data have been derived from continuous phase III studies. Now that the preparation has been introduced in several countries, the opportunity to assemble comprehensive experience has been taken by initiating phase IV studies. Documentation on 600,000 therapy cycles with monophasic gestodene among 100,000 women is already available. The drop-out rate was low. A large number of women participated in the clinical studies for a long time--some up to 3 years. Study results showed that contraceptive reliability was high and cycle control was excellent. The gestodene combination was well tolerated. The frequency of concomitant symptoms was low. The monophasic gestodene meets the basic criteria essential for an oral contraceptive.

Recommendation for confidence interval and sample size calculation for the Pearl Index

A new guideline on the clinical investigation of steroid contraceptives in women, which has been released by the European Agency for the Evaluation of Medicinal Products (EMEA), calls for the calculation of a confidence interval for the Pearl Index, a widely used measure to describe the effectiveness of a contraceptive method. However, the interpretation of the Pearl Index as a statistical parameter, for which a confidence interval can be calculated, needs further clarification. The guideline does not provide the necessary definitions. In this paper, two statistical models, the Bernoulli model and the Poisson model, are compared; both can be used for the calculation of the Pearl Index and its upper confidence limit. The Poisson model proved to be more suitable, because it can accommodate incomplete treatment cycles. Unambiguous definitions and statistical formulae for the calculation of overall Pearl Index and the Method Failure Pearl Index are given. Finally, the sample sizes required to fulfill the EMEAs guideline are given.

Double-blind, multicenter comparison of efficacy, cycle control, and tolerability of a 23-day versus a 21-day low-dose oral contraceptive regimen containing 20 μg ethinyl estradiol and 75 μg gestodene

This prospective, double-blind, randomized study was conducted to compare the contraceptive reliability, cycle control, and tolerability of a 23-day versus a 21-day oral contraceptive regimen containing 20 microg ethinyl estradiol and 75 microg gestodene. Participants took trial medication daily for 28 days, either 23 tablets with active substances plus 5 placebo tablets or 21 tablets with active substances plus 7 placebo tablets. Contraceptive efficacy, cycle control, and tolerability were evaluated over a period of seven cycles. Efficacy data gathered from 4,878 treatment cycles (23-day regimen: 2,362 cycles; 21-day regimen: 2,516 cycles) were obtained from 703 participants (23-day regimen, n = 342; 21-day regimen, n = 361). Both preparations proved to be effective contraceptives and provided good cycle control. One pregnancy because of method failure was recorded in each treatment group. This resulted in a study Pearl Index of 0.5 for each treatment. For the 23-day regimen, 36.0% of participants reported at least one intracyclic bleeding episode during Cycles 2-4 (primary target) compared to 37.1% in the 21-day regimen. In the 23-day regimen group, intracyclic bleeding episodes were reported by 42.4% of the participants in Cycle 1 but only in 14% in Cycle 7 and in the 21-day regimen group by 44.6% in Cycle 1 and only 17.3% in Cycle 7. Overall, intracyclic bleeding was reported in 21.9% of the 23-day regimen cycles and in 22.7% of the 21-day regimen cycles.A greater number of 23-day regimen participants had shorter withdrawal bleeding periods than with the 21-day regimen. In significantly (p <0.0001) more cycles in the 23-day regimen group, participants reported withdrawal bleeding periods that lasted only 1-4 days compared to the 21-day regimen group. For the majority of the treatment cycles, the median number of bleeding days in the 23-day regimen group was 4 days and in the 21-day regimen group 5 days. Both preparations were well tolerated and showed a similar adverse events pattern. The discontinuation rate because of adverse events was low (23-day regimen, 6%; 21-day regimen, 4%). No serious vascular adverse events were reported. More than 75% of the women in both groups either lost more than 2 kg of weight or did not gain weight during the study. The treatment effect on blood pressure was negligible. There were no appreciable changes in mean laboratory values over the course of the study.