Bayer HealthCare Pharmaceuticals, Inc. is aware of two studies published today in The British Medical Journal, ONLINE FIRST. These papers are "Risk of venous thromboembolism in users of oral contraceptives containing drospirenone or levonorgestrel: nested case-control study based on UK General Practice Research Database" by Lianne Parkin et al; and "Risk of non-fatal venous thromboembolism in women using oral contraceptives containing drospirenone compared with women using oral contraceptives containing levonorgestrel: case-control study using United States claims data" by Susan S. Jick et al.
Bayer's assessment, based on its review to date, is that the manner in which the authors applied the study methodology reported in these two publications and the databases used provide less reliable conclusions than are available from existing scientific evidence around the risk of developing venous thromboembolism (VTE), or blood clots, with combination oral contraceptives (COCs). Given the already large and robust scientific body of evidence, in Bayer's opinion, these studies do not change the overall assessment about the safety of Bayer's oral contraceptives. Bayer re-affirms that the overall body of available scientific evidence continues to provide support that the risk of developing venous thromboembolism (VTE), or blood clots, in women using drospirenone-containing combination oral contraceptives (COCs) is comparable to other combination birth control pills studied.
"Bayer has sponsored several independently-conducted, large-scale, prospective, observational safety studies on the use of combined oral contraceptives (COCs), including the EURAS Study and LASS follow up study, the Ingenix Study and the INAS Study" said Leo Plouffe, MD, Vice President, US Medical Affairs, Women's HealthCare, Bayer HealthCare Pharmaceuticals. "Bayer's assessment that its drospirenone-containing COCs are safe and effective when taken as directed according to prescribing information is supported by consistent clinical findings over a 15 year period and up to 10 years of post-marketing study results which support that the risk of VTE is similar with any COC studied, regardless of the progestin."
Combination oral contraceptives are among the most systematically studied and widely-used medicines available today. Bayer's combined oral contraceptives have been and continue to be extensively studied worldwide.
The above referenced study protocols have been reviewed by regulatory authorities in both Europe (EMA) and the USA (FDA). They have also been acknowledged by many experts in the field as among the most comprehensive and best-designed studies of their kind. These studies continue to build on a large established body of well-grounded data about the safety of oral contraceptives with study designs that allow for control of key confounding factors and minimize the risk of bias. Importantly, data from these studies have consistently shown that the risk of VTE with drospirenone is comparable to that seen with other progestins, including levonorgestrel.
"The EURAS and Ingenix studies are already reflected in an April 2010 FDA-approved US label update for YAZ® (3 mg drospirenone / 0.02 mg ethinyl estradiol) and Yasmin® (3 mg drospirenone/ 0.03 mg ethinyl estradiol)," Dr. Plouffe continued. "As science has developed, so too has the need and demand for more detailed information and methods that help us control for confounders. With the EURAS and INAS Studies, we had the right mechanism in place to observe the risk of VTE in a controlled environment, thus affirming that VTE risk is comparable across any combined oral contraceptives studied, with similar dosages of a progestin."
All birth control pills, including Bayer's, carry an increased risk of blood clots, stroke and heart attack. These serious side effects are rare. Oral contraceptives increase the tendency to develop strokes (stoppage or rupture of blood vessels in the brain) and heart attacks (blockage of blood vessels in the heart). Blood clots (venous thrombosis) and blockage of blood vessels are a serious side effect of taking oral contraceptives. VTE is an uncommon event among women using combined oral contraceptives, and pregnancy increases the risk of VTE as much or more than the use of COCs.
Women should not use YAZ or Yasmin if they smoke and are over age 35. Smoking increases the risk of serious side effects from the Pill, which can be life-threatening, including blood clots, stroke or heart attack. This risk increases with age and number of cigarettes smoked.
Women should not use YAZ or Yasmin if they have kidney, liver, or adrenal disease because this could cause serious heart and health problems, or if they have or have had blood clots, certain cancers, history of heart attack or stroke, or if they are or may be pregnant. YAZ and Yasmin increase the risk of serious conditions including blood clots, stroke and heart attack. Smoking increases these risks, especially in women over 35. The risk of blood clots is highest during the first year of use.
In addition, YAZ and Yasmin contain drospirenone, a different kind of hormone that for some may increase potassium too much. Therefore, women should not take YAZ or Yasmin if they have kidney, liver, or adrenal disease because this could cause serious heart and health problems. Women who are on daily, long-term treatment for a chronic condition with medications that may also increase potassium, should consult with their healthcare provider as they should have a blood test to check their potassium level during the first month of taking YAZ or Yasmin.