The FDA has approved Kyleena (levonorgestrel-releasing intrauterine system, Bayer), a progestin-containing intrauterine device, for the prevention of pregnancy for up to five years. The product will be available by prescription in October 2016.
Kyleena is a small, flexible plastic T-shaped IUD containing 19.5 mg of the progestin hormone levonorgestrel. The device is placed by a health care provider during an in-office visit and prevents pregnancy for up to five years. It may be removed by a health care provider at any time.
Because Kyleena slowly releases levonorgestrel into a woman’s uterus, only small amounts of the hormone enter the blood. For the first three to six months, a woman’s period may become irregular, and the number of bleeding days may increase. Women may also have frequent spotting or light bleeding. Some women have heavy bleeding during this time. After using Kyleena for a while, the number of bleeding and spotting days is likely to lessen. For some women, periods will stop altogether. When Kyleena is removed, menstrual periods should return.
The contraceptive efficacy of Kyleena was evaluated in a clinical trial in which 1,452 generally healthy women (18 to 35 years of age) received Kyleena. Of these women, 40% (574) were nulliparous; 60% (870) had completed three years of the study; 49% (707) elected to enroll in an extension phase up to a total of five years; and 38% (550) completed five years of use. The randomized, open-label study was conducted in the United States, Canada, Europe, and Latin America.
The trial’s primary efficacy endpoint was the pregnancy rate, determined by the Pearl Index (PI), to assess contraceptive reliability. The PI was calculated based on 28-day equivalent exposure cycles; evaluable cycles excluded those in which back-up contraception was used unless a pregnancy occurred during that cycle. The cumulative five-year pregnancy rate was based on 13 pregnancies that occurred after the onset of treatment and within seven days after Kyleena removal or expulsion.
The PI pregnancy rates during the study were 0.16 at year 1; 0.38 at year 2; 0.45 at year 3; 0.15 at year 4; and 0.37 at year 5. The cumulative five-year Kaplan Meier pregnancy rate was 1.45.
Of the Kyleena-treated women, 22% discontinued treatment because of an adverse event; 5% were lost to follow-up; 2% withdrew for unspecified reasons; 1% discontinued because of a protocol deviation; less than 1% discontinued because of pregnancy; and 20% discontinued because of other reasons.
Approximately 71% of 163 women who wanted to become pregnant were able to do so within 12 months after removal of the Kyleena device.
Source: Bayer; September 19, 2016.