Recommendations for the Use of Antiretroviral Drugs During Pregnancy and Interventions to Reduce Perinatal HIV Transmission in the United States

Entry and Attachment Inhibitors

Maraviroc (Selzentry, MVC)

Summary

• No dose adjustments are required for maraviroc (MVC) during pregnancy. The dose of MVC should be determined after accounting for potential drug interactions with concomitantly administered medications, including antiretroviral (ARV) drugs.
• Clinical data are insufficient to characterize the risk for congenital anomalies associated with in utero exposure to MVC.
• No reproductive toxicity or teratogenicity concerns were identified in animal studies.

Human Studies in Pregnancy

Pharmacokinetics

A U.S.–European intensive pharmacokinetic (PK) study measured 12-hour PK profiles in the third trimester and at least 2 weeks postpartum of 18 women who were taking MVC as part of clinical care.¹ Sixty-seven percent of the women in the study were taking MVC 150 mg twice daily with a protease inhibitor, 11% took MVC 300 mg twice daily, and 22% took an alternative regimen. The geometric mean ratio for third-trimester area under the curve (AUC) versus postpartum AUC was 0.72 (90% confidence interval [CI], 0.60–0.88); the geometric mean ratio for maximum MVC concentration in the third trimester versus maximum MVC concentration postpartum was 0.70 (90% CI, 0.58–0.85). Despite an overall 30% decrease in MVC AUC during pregnancy and a 15% decrease in trough concentration (C_trough), C_trough exceeded the minimum target concentration of 50 ng/mL in all participants except for one woman, who had a C_trough below 50 ng/mL during both pregnancy and the postpartum period. These data suggest that the standard adult dose adjusted for concomitant ARV drugs is appropriate in pregnancy. A review of interactions between ARV drugs and oral contraceptives found that it is safe to coadminister oral contraceptives with MVC.²

Placental and Breast Milk Passage

In a study of six mother–infant pairs, the median ratio of MVC concentration in cord blood to MVC concentration in maternal plasma was 0.33 (with a range of 0.03–0.56), indicating moderate placental transfer.¹ An ex vivo human placental cotyledon perfusion model demonstrated minimal placental passage of MVC.³ This may be due to the activity of multiple transporters (e.g., multidrug resistance-associated protein 1, organic anion transporting polypeptide 1A2, organic anion transporting polypeptide 1B3) that drive MVC away from fetal circulation into placental tissue, as demonstrated in a closed-circuit perfusion study of MVC across human placental cotyledon.⁴ Whether MVC is secreted into human milk is unknown.

Teratogenicity/Adverse Pregnancy Outcomes

Thirty-one cases of first-trimester exposure to MVC have been reported to the Antiretroviral Pregnancy Registry to date,⁵ and other first-trimester exposure data are available.⁶ Data are still insufficient, however, to determine the risk of birth defects for infants who were exposed to MVC.

Other Safety Information

A retrospective study from an English–Irish cohort of 857 pregnant women showed an increased rate of hepatotoxicity among the 492 women who started ARV therapy during pregnancy.⁷ MVC, efavirenz, and nevirapine were associated with an increased risk of liver enzyme elevation during pregnancy; the adjusted hazard ratio for MVC was 4.19 (1.34–13.1, P = 0.01). In a model that used human placental BeWo cells, MVC inhibited transplacental passage of two fluorescent organic cations, suggesting that MVC might influence placental drug transfer and cause drug–drug interactions.⁸

Animal Studies

Carcinogenicity

MVC was neither mutagenic nor clastogenic in a series of in vitro and animal in vivo screening tests. Long-term carcinogenicity studies of MVC in rats showed no drug-related increases in tumor incidence at exposures that were approximately 11 times those observed in humans who received the therapeutic dose.

Reproduction/Fertility

No adverse effects were observed on the fertility of male or female rats at doses of MVC that produced exposures (based on AUC) up to 20-fold higher than those seen in humans given the recommended 300-mg, twice-daily dose.

Teratogenicity/Adverse Pregnancy Outcomes

In animal reproduction studies, no evidence of adverse developmental outcomes was observed in animals that received MVC. During organogenesis in the rat and rabbit, systemic exposures to MVC (based on AUC) were approximately 20 times (in rats) and five times (in rabbits) the exposure seen in humans given the recommended 300-mg, twice-daily dose. In a rat prenatal and postnatal development study, maternal MVC AUC was about 14 times the exposure observed in humans given the recommended 300-mg, twice-daily dose.⁹

Placental and Breast Milk Passage

A study in rhesus macaques showed that single-dose MVC had poor placental transfer and rapid clearance from infant monkeys’ blood.¹⁰ Studies in lactating rats indicate that MVC is secreted extensively into rat milk.⁹

Excerpt from Table 14

References

1. Colbers A, Best B, Schalkwijk S, et al. Maraviroc pharmacokinetics in HIV-1-infected pregnant women. Clin Infect Dis. 2015;61(10):1582-1589. Available at: http://www.ncbi.nlm.nih.gov/pubmed/26202768.
2. Tittle V, Bull L, Boffito M, Nwokolo N. Pharmacokinetic and pharmacodynamic drug interactions between antiretrovirals and oral contraceptives. Clin Pharmacokinet. 2015;54(1):23-34. Available at: http://www.ncbi.nlm.nih.gov/pubmed/25331712.
3. Vinot C, Gavard L, Treluyer JM, et al. Placental transfer of maraviroc in an ex vivo human cotyledon perfusion model and influence of ABC transporter expression. Antimicrob Agents Chemother. 2013;57(3):1415-1420. Available at: http://www.ncbi.nlm.nih.gov/pubmed/23295922.
4. Tupova L, Hirschmugl B, Sucha S, et al. Interplay of drug transporters P-glycoprotein (MDR1), MRP1, OATP1A2, and OATP1B3 in passage of maraviroc across human placenta. Biomed Pharmacother. 2020;129:110506. Available at: https://www.ncbi.nlm.nih.gov/pubmed/32768979.
5. Antiretroviral Pregnancy Registry Steering Committee. Antiretroviral Pregnancy Registry international interim report for 1 January 1989–31 January 2023. Morrisville, NC: Registry Coordinating Center; 2023.Available at: http://www.apregistry.com/. 
6. Floridia M, Mastroiacovo P, Tamburrini E, et al. Birth defects in a national cohort of pregnant women with HIV infection in Italy, 2001–2011. BJOG. 2013;120(12):1466-1475. Available at: http://www.ncbi.nlm.nih.gov/pubmed/23721372.
7. Huntington S, Thorne C, Anderson J, et al. Does pregnancy increase the risk of ART-induced hepatotoxicity among HIV-positive women? J Int AIDS Soc. 2014;17(4 Suppl 3):19486. Available at: http://www.ncbi.nlm.nih.gov/pubmed/25393995.
8. Nabekura T, Kawasaki T, Kamiya Y, Uwai Y. Effects of antiviral drugs on organic anion transport in human placental BeWo cells. Antimicrob Agents Chemother. 2015;59(12):7666-7670. Available at: http://www.ncbi.nlm.nih.gov/pubmed/26416870.
9. Maraviroc (Selzentry) [package insert]. U.S. Food and Drug Administration. 2020. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/022128Orig1s019,208984Orig1s002lbl.pdf.
10. Winters MA, Van Rompay KK, Kashuba AD, Shulman NS, Holodniy M. Maternal-fetal pharmacokinetics and dynamics of a single intrapartum dose of maraviroc in rhesus macaques. Antimicrob Agents Chemother. 2010;54(10):4059-4063. Available at: http://www.ncbi.nlm.nih.gov/pubmed/20696881.