A Pharmacokinetic Evaluation of Levonorgestrel Implant and Antiretroviral Therapy

Summary

The use of hormone contraception poses a significant challenge for the estimated 16 million HIV-infected women of childbearing age. This is due to known drug interactions with antiretroviral therapy (medicines used to treat HIV) that may jeopardize contraception effectiveness. By evaluating the impact of antiretroviral therapy on a levonorgestrel subdermal implant, the most widely available hormone implant in low and middle-income countries, this study will translate its findings into an evidence-based approach to co-manage these important medications. The investigators hypothesize that women receiving nevirapine or efavirenz-based antiretroviral therapy will have a significant decrease in the mean levonorgestrel plasma concentration measured six months after the implant's insertion as compared to those women who are not taking antiretroviral therapy. Although the implant's efficacy may be retained initially, the investigators propose that a decrease in levonorgestrel concentrations in women receiving antiretroviral therapy may jeopardize the implant's effectiveness near the end of its intended duration of use (5 years).

Timeline

Start

2014-03-04

Primary completion

2014-09-01

Completion

2015-03-04

Publications

• Results Scarsi KK*, Darin KM, Nakalema S, Back D, Byakika-Kibwika P, Else L, Dilly-Penchala S, Cohn S, Merry C, Lamorde M. Levonorgestrel implant + EFV-based ART: Unintended pregnancies and associated PK Data. Conference on Retroviruses and Opportunistic Infections. Seattle, WA. February 23-26, 2015. Abstract #85LB.
• Results Scarsi K, Lamorde M, Darin K, Penchala SD, Else L, Nakalema S, Byakika-Kibwika P, Khoo S, Cohn S, Merry C, Back D. Efavirenz- but not nevirapine-based antiretroviral therapy decreases exposure to the levonorgestrel released from a sub-dermal contraceptive implant. J Int AIDS Soc. 2014 Nov 2;17(4 Suppl 3):19484. doi: 10.7448/IAS.17.4.19484. eCollection 2014.
• Results Scarsi KK, Darin KM, Nakalema S, Back DJ, Byakika-Kibwika P, Else LJ, Dilly Penchala S, Buzibye A, Cohn SE, Merry C, Lamorde M. Unintended Pregnancies Observed With Combined Use of the Levonorgestrel Contraceptive Implant and Efavirenz-based Antiretroviral Therapy: A Three-Arm Pharmacokinetic Evaluation Over 48 Weeks. Clin Infect Dis. 2016 Mar 15;62(6):675-682. doi: 10.1093/cid/civ1001. Epub 2015 Dec 8.

Drugs

Indications