Statement on combined hormonal contraceptives containing third- or fourth-generation progestogens or cyproterone acetate, and the associated risk of thromboembolism

Assessing the Impact on Health of Pharmacovigilance Activities: Example of Four Safety Signals

INTRODUCTION

The impact of pharmacovigilance activities on public health remains under-investigated, and measuring the impact on health of pharmacovigilance activities for a specific safety signal is challenging.

OBJECTIVE

To gain more insight into the methodological challenges and the data required, we assessed the impact of pharmacovigilance on public health for four identified product-specific safety signals using publicly available data in the Netherlands. The assessment was on the impact of the intertwined and complementary steps of the pharmacovigilance pathways.

METHODS

The impact of pharmacovigilance on public health was assessed using the assessment support tool and 'open data' from the Netherlands for four different types of pharmacovigilance safety signals: (1) off-label use of cyproterone acetate/ethinyloestradiol (CPA/EE) and thrombotic risk after pharmacovigilance measures after 2014; (2) pergolide and the risk of cardiac valvulopathy after pharmacovigilance activities in 2003; (3) proton pump inhibitors and the risk of hypomagnesaemia after pharmacovigilance activities in 2011; (4) rosiglitazone withdrawal from the market because of cardiovascular effects in 2010.

RESULTS

For the signals on CPA/EE and pergolide, a crude estimation of the impact could be made with varying degrees of assumptions based on the risk described in the literature and utilisation data.

CONCLUSION

This article highlights the methodological challenges and the data required to assess the impact of product-specific safety signals. A structured assessment support tool can be used as a guide for the necessary data elements and steps needed for the measurement or estimation of impact of pharmacovigilance activities on public health, provided that the appropriate data are available.

Combined hormonal contraceptive use in Europe before and after the European Commission mandated changes in product information

Objectives

We investigated combined hormonal contraceptives (CHC) prescribing patterns (focusing on combined oral contraceptives; COC) in three countries (Netherlands, Denmark, United Kingdom) in a time period preceding and in a time period following the European Commission's decision to update product information, and we estimated changes in incidence of venous thromboembolism (VTE) between the two periods.

Study design

We conducted a drug utilization analysis and a cohort study using routinely collected data. We calculated number, proportion and incidence rate of new users, switchers, and stoppers of COC in both time periods. VTE incidence was calculated in new users of COC and in all women aged 18–49 years.

Results

In all countries, the largest proportion (> 75%) of new users used COC containing levonorgestrel, norethisterone, or norgestimate, (i.e., indicated by European Medicines Agency (EMA) as the safest preparations) in both time periods. Switching did not demonstrate a clear pattern towards these types of COC and distribution of stoppers was similar in both time periods. While the proportion of new users initiating COC containing levonorgestrel, norethisterone, or norgestimate increased slightly, this did not translate to a decrease in the overall VTE incidence.

Conclusion

All three countries had the greatest proportion of women initiating a COC containing levonorgestrel, norethisterone, or norgestimate, and this proportion increased in the period after the European Commission decision albeit the increase was small due to the high percentage of use before the decision. This did not translate into a measureable change in the incidence of VTE.

Implications

Both before and after the European Commission's decision, the largest proportion of new users started with combined oral contraceptives containing levonorgestrel, norethisterone, or norgestimate. Earlier studies had already indicated an increased risk of VTE associated with COC containing other progestogens compared with these preparations, so it is possible that physicians were already preferentially prescribing COC containing levonorgestrel, norethisterone, or norgestimate to new users.

The incidence and prognosis of thromboembolism associated with oral contraceptives: Age-dependent difference in Japanese population

Aim

We analyzed the incidence and prognosis of thromboembolism associated with combined oral contraceptives (COCs) by age groups in Japan.

Methods

A total of 581 events of venous thromboembolism (VTE) and arterial thromboembolism (ATE) associated with COCs were analyzed from the Pharmaceuticals and Medical Devices Agency database from 2004 to 2013. In a statistical analysis, a good‐prognosis group included recovery cases and a poor‐prognosis group involved unrecovered cases with some sequela and fatal cases. The significant difference between these two groups was calculated by Pearson's chi‐square test, and the age‐specific tendency and the trend of differences in prognosis according to different hormonal contraceptives were examined by Cochran–Armitage trend test.

Results

A total of 543 events were analyzed except 38 events due to unknown age, in which DVT only was the most frequent, followed by cerebral infarction, PE with DVT, PE only, cerebral vein thromboses. ATE ratio for overall thromboembolism tended to increase with advancing age (P = 0.0041). Good‐prognosis group was common (291 cases in VTE and 83 cases in ATE), followed by poor‐prognosis group (46 cases in VTE and 34 cases in ATE). All ATE cases had a significantly poorer prognosis in comparison with all VTE cases (P < 0.0001). Types of progestin and age difference, however, showed no trend in the differences between good‐prognosis group and poor‐prognosis group (P = 0.3548 and P = 0.6097).

Conclusion

Thromboembolic events were the most frequent in the 40s. The ATE ratio for overall thromboembolism tended to increase with advancing age. All ATE cases had a significantly poorer prognosis in comparison with all VTE cases.

Risks of thromboembolism associated with hormone contraceptives in Japanese compared with Western women

We extracted 581 thromboembolic events associated with combined oral contraceptives (COC) that occurred between 2004 and 2013 in Japan, from the Pharmaceuticals and Medical Devices Agency database. The most common thromboembolic events associated with COC were deep vein thrombosis, pulmonary embolism and their combination. The reported thromboembolic events increased year by year, in association with an increase in the quantity of prescribed low-dose estrogen progestin after approval for health insurance coverage for dysmenorrhea in 2008 in Japan. The incidence of venous thromboembolism (VTE) in Japanese COC users is estimated to be lower compared with their Western counterparts. In contrast, the frequency of all thromboembolic events peaked at 90 days from the start of COC, as in Western studies. The risk of VTE in the overweight group (body mass index ≥ 25 kg/m² ) was more than twofold higher than in the standard group, and age-specific incidence rate rose sharply after the age of 40. There were different VTE risks according to progestin type in Japan as in Western countries, but a definite conclusion about risk according to progestin type was not able to be reached at present. As for the risk of arterial embolism and thrombosis, the difference by progestin type was small, but it became higher at ≥50 years of age. Last, mortality rate caused by thromboembolism is extremely low among COC users.

Low dose oestrogen combined oral contraception and risk of pulmonary embolism, stroke, and myocardial infarction in five million French women: cohort study

OBJECTIVE

To assess the risk of pulmonary embolism, ischaemic stroke, and myocardial infarction associated with combined oral contraceptives according to dose of oestrogen (ethinylestradiol) and progestogen.

DESIGN

Observational cohort study.

SETTING

Data from the French national health insurance database linked with data from the French national hospital discharge database.

PARTICIPANTS

4 945 088 women aged 15-49 years, living in France, with at least one reimbursement for oral contraceptives and no previous hospital admission for cancer, pulmonary embolism, ischaemic stroke, or myocardial infarction, between July 2010 and September 2012.

MAIN OUTCOME MEASURES

Relative and absolute risks of first pulmonary embolism, ischaemic stroke, and myocardial infarction.

RESULTS

The cohort generated 5 443 916 women years of oral contraceptive use, and 3253 events were observed: 1800 pulmonary embolisms (33 per 100 000 women years), 1046 ischaemic strokes (19 per 100 000 women years), and 407 myocardial infarctions (7 per 100 000 women years). After adjustment for progestogen and risk factors, the relative risks for women using low dose oestrogen (20 µg v 30-40 µg) were 0.75 (95% confidence interval 0.67 to 0.85) for pulmonary embolism, 0.82 (0.70 to 0.96) for ischaemic stroke, and 0.56 (0.39 to 0.79) for myocardial infarction. After adjustment for oestrogen dose and risk factors, desogestrel and gestodene were associated with statistically significantly higher relative risks for pulmonary embolism (2.16, 1.93 to 2.41 and 1.63, 1.34 to 1.97, respectively) compared with levonorgestrel. Levonorgestrel combined with 20 µg oestrogen was associated with a statistically significantly lower risk than levonorgestrel with 30-40 µg oestrogen for each of the three serious adverse events.

CONCLUSIONS

For the same dose of oestrogen, desogestrel and gestodene were associated with statistically significantly higher risks of pulmonary embolism but not arterial thromboembolism compared with levonorgestrel. For the same type of progestogen, an oestrogen dose of 20 µg versus 30-40 µg was associated with lower risks of pulmonary embolism, ischaemic stroke, and myocardial infarction.

Oral steroid contraception

Oral steroid contraception is a popular method of family planning worldwide. Over the past several decades, this method of contraception has changed significantly by decreasing the estrogen dose, changing the progestin component, and reducing the hormone free interval. Despite the popularity of oral steroid contraception, there has been much criticism regarding the associated risks of venous thromboembolism and stroke. Despite these established, yet uncommon risks, oral steroid contraception has many important health benefits. This review highlights the available formulations of oral contraceptives along with their evidence-based associated risks and benefits. Highlights regarding future directions for development of novel oral contraceptives are also addressed.

Does the Progestogen Used in Combined Hormonal Contraception Affect Venous Thrombosis Risk?

Combined hormonal contraceptives (CHCs) use a combination of estrogen and progestogen to provide contraception. The most important risk of using CHCs is venous thromboembolism (VTE). It is unclear whether the type of progestogen used in a method augments that risk. Although the evidence supporting an increase in thrombosis risk is not conclusive, neither is the evidence supporting the benefit of newer progestogens in terms of tolerability or continuation. The benefits of CHCs outweigh the risks and the absolute risk of VTE remains small. A balanced discussion of potential risks and benefits of particular CHC formulations is warranted during contraception counseling.

Effect of information on the perception of users and prospective users of combined oral contraceptives regarding the risk of venous thromboembolism

This study evaluated patients' knowledge on the risk of venous thromboembolism (VTE) associated with combined oral contraceptives (COCs) and their perception of this risk when it is presented as a relative risk (RR), absolute risk (AbR) or attributable risk (AR). This was a cross-sectional study involving 159 users or potential users of COCs. The participants answered a self-administered questionnaire in which the risk of VTE associated with COCs was presented as RR, AbR and AR. The degree of concern expressed regarding this risk and the women's changes of opinion when the information was communicated through a different risk model were evaluated. Most of the women (67.9%) expressed concern when the risk was presented as an RR. Conversely, they showed no concern when the risk was presented as an AbR (14.5%) or AR (10.7%). A significant number of women changed their opinion regarding their level of concern when the risk was presented as an AbR or AR (p < 0.001). In conclusion, concerns about thrombotic complications from the use of combined hormonal contraception is reduced when incidence rather than relative risk is presented. Presentation of thrombosis complications in terms of incidence rather than RR may improve communication of side effects during counseling for combined hormonal contraception initiation.

Trends and patterns of hormonal contraceptive prescribing for adolescents in primary care in the U.K

BACKGROUND

Hormonal contraceptives are the most common method used worldwide by teenagers to prevent unwanted pregnancies. To date there are limited data about such use by teenagers in the UK. This study investigated trends and patterns of hormonal contraceptive prescribing to adolescents aged 12-18 years in UK primary care between 2002 and 2011.

METHODS

A retrospective cohort study using the IMS Disease Analyzer database was conducted. All females aged 12-18 years with ≥1 prescription for a contraceptive drug between 1 January 2002 and 31 December 2011 were included. Annual prevalence of contraceptive drug prescribing was calculated, and indications for prescribing, and types of contraceptive drug prescribed, were examined.

RESULTS

In 2002, 13.7% (6135/44 532) of female adolescents received prescriptions for hormonal contraceptives, compared to 19.0% (6597/34 676) in 2011. The majority of female adolescents [2002: 76.2% (4676/6135); 2011: 65.7% (4334/6597)] received a contraceptive drug for 'contraceptive management'. The combined oral contraceptive (COC), 'progestogen+estrogen', was the most commonly prescribed. Although use of progestogen-only contraceptives was lower than COCs, the number of patients who received desogestrel pills and etonogestrel implants increased during the study period; levonorgestrel pill use declined. Only one injectable progestogen, long-acting depot medroxyprogesterone acetate, was prescribed.

CONCLUSIONS

Use of hormonal contraceptives among adolescents increased between 2002 and 2011, and COC usage was dominant. The increasing use of hormonal contraceptives in adolescents, especially in younger adolescents, warrants further investigation, including research into the long-term safety of these medicines in this age group.

Contraceptive needs of the adolescent

The provision of contraception to adolescents requires specific attention. Adolescents require contraceptive methods which are safe, effective and simple to use. While long-acting reversible contraceptive methods are preferable, they should have a choice and not be forced or mandated especially in situations where this may compromise safety. After counselling they should have the ability to choose any method of contraception. Under the appropriate circumstances, each method of contraception may have a place. This chapter will be devoted to evaluating the most current scientific rationale for the indication for use of each method of contraception in adolescents.

Effect of a low-dose contraceptive patch on efficacy, bleeding pattern, and safety: a 1-year, multicenter, open-label, uncontrolled study

This Phase III, uncontrolled, open-label, multicenter study was conducted to investigate the contraceptive efficacy, bleeding pattern, and cycle control of a novel once-a-week contraceptive patch, delivering low-dose ethinyl estradiol (EE) and gestodene (GSD) at the same systemic exposure seen after oral administration of a combined oral contraceptive containing 0.02 mg EE/0.06 mg GSD. Participants were women aged 18 to 35 years, all of whom received the EE/GSD patch for 13 cycles each of 21 treatment days (one patch per week for 3 weeks) followed by a 7-day, patch-free interval. The primary efficacy variable was the occurrence of unintended pregnancies during the study period as assessed by life table analysis and the Pearl Index. Secondary efficacy variables were days with bleeding during four 90-day reference periods and during 1 treatment year, bleeding pattern, and cycle control. The Kaplan-Meier probability of contraceptive protection after 364 treatment days was 98.8% and the adjusted Pearl Index was 0.81. The percentage of participants with intracyclic bleeding/spotting decreased over time, from 11.4% to 6.8% in cycles 1 and 12, respectively. Almost all participants (range: 90.8%-97.6%) experienced withdrawal bleeding across the study period. Compliance was very high (mean: 97.9%; median: 100%). The most frequent adverse events were headache (9.5%) and application site reaction (8.5%); no clinically significant safety concerns were observed. Results suggest the EE/GSD patch is highly effective in preventing pregnancy. Menstrual bleeding pattern was favorable and within the ranges expected of a healthy female population. The patch was well tolerated and treatment compliance was high.