Jessica Maria Atrio, MD, has demonstrated that a safe but less-frequently prescribed birth control "mini-pill" is effective for women taking HIV medications. Study title: Effect of protease inhibitors on pharmacokinetics of oral norethindrone contraception in hiv+ women Read the full story: http://sc-ctsi.org/index.php/news/sc-ctsi-supported-research-drives-global-health-policy#.Ut2b6WTTktU

1. EFFECT OF PROTEASE INHIBITORS ON PHARMACOKINETICS OF ORAL NORETHINDRONE
CONTRACEPTION IN HIV+ WOMEN
Jessica Atrio, Frank Stanczyk, Alice Stek, Andrea Kovacs, Laura Sech, Penina Segall-Gutierrez, Daniel Mishell
Department of Obstetrics & Gynecology, Keck School of Medicine, Los Angeles, CA
OBJECTIVE
To Compare area under the time-concentration curve (AUC) of serum norethindrone (NET) 0
to 72 hours following oral administration of 0.35 mg NET in HIV+ women taking PI (study
group) with NET AUC in women taking anti-retovirals (ARV) without protease inhibitors PI
(control group).
Secondary objectives: to compare minimum plasma concentration, maximum plasma
concentration, time to Cmax, and half-life of NET in both groups
BACKGROUND
 HIV+ women are a high-risk population in need of safe and effective contraception.
 ARV agents are used to treat HIV.
 ARV regimens often contain PI.
 PIs alter hepatic enzyme systems including CYP 3A41
 PI may alter the bioavailability of concurrently administered medications
 Small trials demonstrated an interaction between combined oral contraceptives (COC) and
ARV with PI2
 Plasma ethinyl estradiol levels are decreased
There have been several trials noting no significant change in NET levels
CDC categorize PI + progestin-only pills (POP) as Class 3 based on trials with COC3
Limits POP use in HIV+ women
No published pharmacokinetic (PK) trials of POP in HIV+ women taking ARV with PI
CONCLUSION
METHODS
21 days oral NET 0.35 mg was ingested to obtain steady state NET levels.
10 serum samples were collected for 72 hours after NET ingestion to obtain PK
measurements.
Data are presented as medians and interquartile range (IQR) for continuous data and n (%)
for categorical data. Differences between the groups were compared using Wilcoxon rank
sum test for continuous data and Fisher's exact test for categorical data.
Calculation of NET geometric mean ratio of AUC0-72 by trapezoidal approximation.
Log-transformed control and PI group AUCs were compared with Student’s T-test.
Table 1. Demographic Characteristics
PI*
No PI*
16
17
39.9 (35.9-42.3)
38 (33.4-41.3)
0.60
3 (9.1)
0 (0)
0.10
2.5 (1-4)
3.0 (2-4)
0.30
Intake CD4 (cells/mm3) (IQR)
618.5 (398.0-883.5)
669 (479-749)
0.65
Opportunistic infections** (%)
5 (31.1)
4 (23.5)
0.71
26.8 (25.5-33.8)
29 (24.1-32.8)
0.90
3 (18.8)
2 (11.8)
0.66
N
Age at enrollment* (IQR)
Nulliparous (%)
Parity (IQR)
P-value
• Serum NET AUC 0 to 72 hours is significantly increased among HIV+ women taking PI
therapy as compared to controls.
• In vivo PI therapy in conjunction with POP inhibits NET metabolism with significantly
increased serum levels of NET
• Increased serum NET levels provide therapeutic contraceptive efficacy.
• Compared to COC, POP require less restrictive screening, have wider distribution
potential and can provide an additional safe type of contraception for women with HIV.
• This is the first trial to describe NET POP pharmacokinetics in HIV+ women taking PI
• Data supports increased utilization of POP in HIV+ women taking PI.
• This should alter current POP medical eligibility recommendations for women taking ARV.
Figure 2. Violin Plot of Norethindrone Area under the Curve by Group
DESIGN
This two-arm, open-label, prospective , steady state trial was conducted to characterize PK
of oral NET in HIV+ women taking ARV with and without PI.
Study group: women taking ARV with PI
Control group: women taking ARVs, without PI. In previous COC trials the various ARVs do
not alter NET levels.
Figure 1: Screening, enrollment and study completion
BMI *** (IQR)
Current smoker (%)
*PI protease inhibitor **Opportunistic infections diagnosed in the past
***Body mass index = kg/ m2
RESULTS
Both groups were similar at baseline with regard to age, parity, ethnicity and other
characteristics (Table 2). Participants took multiple medications as per the standard of
care. Other than the PI study group the other ARV medications have demonstrated no
interaction in previous trials. The study group included women taking PI therapy: atazanavir
& ritonavir (N=14), atazanavir (1), darunavir & ritonavir (3), lopinavir & ritonavir (2). The
control group was taking other non-interacting medications including, etravirine, rilpivirine,
tenofovir, emtricitabine and raltegravir. 4 women in the control group were on no ARV
medications.
NET AUC was significantly higher among women taking PI: 37.8 ng*h/ml compared to
controls: : 25.2 ng*h/mL (p=0.004). The ratio of PI to controls was 1.50 (90% CI: 1.21 –
1.86) P value = 0.004
Table 2. Pharmacokinetic Characteristics of Serum Norethindrone (NET) after Oral NET
0.35 mg Ingestion with and without Protease Inhibitor
The width of violin area corresponds to the mass of the data. A traditional box and whisker plot is centered
within each violin, where the filled circle is the median, the lower and upper bounds of the box are the 25th
and 75th percentiles (i.e. the interquartile range [IQR]), the dashed “whiskers” indicate the range of the data
within 1.5 IQR of the box boundaries, and the open circle is an outlier outside this range. Exclusion of this
outlier did not change the results significantly (data not shown).
REFERENCES
1. US Dept. Of Health. Guidance for Industry Drug Interaction Studies (2006)
2. US Dept of Health, Guidelines for the Use of Antiretroviral (2011)
3. U.S. Medical Eligibility Criteria for Contraception use, 2010. CDC, MMWR. 2010; 59
(RR04): 1-85.
* Study group took protease inhibitor (PI) therapy, control group took no PI
**Geometric mean & geometric mean ratio
***Area under curve 0 to 72 hours after oral NET ingestion
Funding for this research was awarded by the Society of Family Planning and the USC CTSI