Silver Spring, MD - Although the US Food and Drug Administration (FDA) has not reached a conclusion, the agency says it remains "concerned" about the approximately 50% increased risk for venous thromboembolism (VTE) among women taking drospirenone-containing oral contraceptives .
In a safety review update released today, the FDA states that it has completed its review of two studies conducted in 2011 evaluating the risk for blood clots in users of various contraceptives. The FDA initially announced the review May 31, saying the studies suggested that a two- to threefold greater risk for VTE in women using oral contraceptives containing drospirenone compared with those using contraceptives containing levonorgestrel. The two studies were originally published online April 21 in BMJ.
Now the FDA says that findings from a separate FDA-funded study indicate an approximately 1.5-fold increase in the risk for blood clots in women who use drospirenone-containing birth-control pills compared with women using other types of hormonal contraceptives. However, the agency says its review of the FDA-funded study is ongoing.
To date, in addition to the FDA-funded study, six published epidemiologic studies have evaluated the risk for VTE and have shown mixed results regarding drospirenone.
Given the conflicting findings, the FDA plans to hold a joint meeting of the Reproductive Health Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee on December 8 to discuss the risks and benefits of drospirenone-containing oral contraceptives, in particular the risk for VTE.
Healthcare providers should inform women currently taking a drospirenone-containing birth-control pill of the potential risk for blood clots, according to the FDA.
"Women who are already taking birth-control pills containing drospirenone should continue taking their pills as directed unless told otherwise by their healthcare professional," the FDA notes. "The risks and benefits of drospirenone-containing birth-control pills for a specific patient should be considered in light of her risk for developing blood clots," the agency adds.
Factors associated with an increased risk for VTE include smoking, being overweight (obesity), and family history of VTE. The FDA recommends that women who are older than 35 years and who smoke should not take any type of combination oral contraceptive (including those containing drospirenone), due to an increased risk for serious cardiovascular events.
The FDA has prepared a list of questions and answers that address this issue and indicate that the agency will "continue to communicate any new information to the public as it becomes available."
More information on today's announcement is available on the FDA website.
Heartwire from Medscape © 2011
Cite this: FDA still "concerned" about drospirenone VTE risk - Medscape - Sep 26, 2011.