Abstract

OBJECTIVE:

To evaluate the effect of an antiretroviral (ARV) therapy regimen containing zidovudine (AZT), lamivudine (3TC), and efavirenz (EFV) on the pharmacokinetics of depot medroxyprogesterone acetate (DMPA).

DESIGN:

Open-label, nonrandomized, clinical trial.

SETTING:

University hospital clinic.

PATIENT(S):

Thirty HIV-infected women; 15 using ARV therapy (AZT, 3TC, and EFV) and 15 non-users of ARV therapy, followed biweekly for 12 weeks.

INTERVENTION(S):

Single injection of DMPA (150 mg IM) for both groups.

MAIN OUTCOME MEASURE(S):

Pharmacokinetic parameters of DMPA by liquid chromatography with mass spectrometry, and ovulation by serum P.

RESULT(S):

Maximum serum concentrations of DMPA were reached at 14 days after injection. The area under the curve was similar in both groups, as were the minimum concentration, half-life, and clearance. Only 1 woman, not using ARV therapy, ovulated at 11 weeks after DMPA.

CONCLUSION(S):

Pharmacokinetics of DMPA were similar in HIV-infected women, regardless of ARV therapy use, suggesting that triple therapy with AZT, 3TC, and EFV is not likely to interfere with the contraceptive effectiveness of DMPA.