Study Of Lybrel In Relation To Venous Thromboembolism

Pfizer598,682 enrolled

Overview

Lybrel® is an oral contraceptive that delivers low doses of levonorgestrel and ethinyl estradiol (90 μg/20 μg). Lybrel is taken on a continuous basis without a placebo or pill-free interval to inhibit menstrual cycle bleeding by delivering a steady level of the 2 hormones for as long as the drug is used. Lybrel was marketed in the US in July of 2007. The objective of this database case-control study is to estimate the risk of idiopathic VTE (deep vein thrombosis and pulmonary embolism) in current users of Lybrel (ethinyl estradiol 20ug/levonorgestrel 90ug) compared to current users of other oral contraceptives containing 20μg of ethinyl estradiol.

The base population consists of all currently available data on current users (15-49 years old) of Lybrel and other oral contraceptives (OC) containing 20 µg ethinyl estradiol in the PharMetrics/IMS and MarketScan databases. From among the base population, the databases are then searched for any diagnosis of deep vein thrombosis (DVT), pulmonary embolism (PE), or cerebral venous sinus thrombosis (CVST) \[referred to collectively as venous thromboembolism or VTE\] that occurred after receipt of Lybrel or other oral contraceptives containing 20 µg ethinyl estradiol. The intent is to include newly diagnosed cases of VTE.

Study Type

OBSERVATIONAL

Enrollment

598,682

Conditions

Venous Thrombosis Pulmonary Embolism Sinus Thrombosis, Intracranial

Interventions

90ug levonorgestrel / 20 ug ethinyl estradiolDRUG

This is a non-interventional observational database study, thus no interventions are offered to patients in the study.

Oral Contraceptives containing 20 ug of ethinyl estradiolDRUG

This is a non-interventional observational database study, thus no interventions are offered to patients in the study.

Outcomes

Primary Outcomes

Incidence Rate of Idiopathic Venous Thromboembolism (VTE)

Idiopathic VTE=deep vein thrombosis (DVT), pulmonary embolism (PE), or cerebral venous sinus thrombosis (CVST) occurring in absence of known risk factors. Incidence rate reported for current, past users. Current user=had claim for study OC prescription (Lybrel or other OCs containing ethinyl estradiol 20 mcg) whose filled use occurred within 30 days prior to or at index date. Past user=had claim for a study OC prescription whose filled use occurred between 90 to 31 days prior to index date. Index date=date of VTE diagnosis for case and corresponding date for matched control.

Time frame: Index date (date of VTE diagnosis for case and corresponding date for matched control)

Number of Idiopathic Venous Thromboembolism (VTE) Cases and Matched Controls

Idiopathic VTE cases=new DVT, PE or CVST occurring in absence of known risk factors. Matched Control was defined as participants with no diagnosis of VTE matched for age, calendar time, exposure status and database. Current user=had claim for study OC prescription (Lybrel or other OCs containing ethinyl estradiol 20 mcg) whose filled use occurred within 30 days prior to or at index date. Past user=had claim for a study OC prescription whose filled use occurred between 90 to 31 days prior to index date. Index date=date of VTE diagnosis for case and corresponding date for matched control.