Pharmacokinetic and pharmacodynamic drug interactions between antiretrovirals and oral contraceptives

Use of nonbarrier contraceptives among women with HIV

OBJECTIVE

The aim of this study was to investigate the use of nonbarrier contraceptives among women with HIV (WWH) compared to women from the general population (WGP) in Denmark.

DESIGN

A nationwide, population-based, matched cohort study.

METHODS

We included WWH aged 16-50 years, treated at an HIV specialized clinic, and included in The Danish HIV Cohort Study between 1995 and 2021 and an age-matched comparison cohort of WGP. We examined use of hormonal contraception, intrauterine devices (IUDs), and sterilization from 10 years before to 20 years after study inclusion. Additionally, we calculated age-standardized proportions and incidences over calendar time.

RESULTS

We included 1720 WWH and 17 720 WGP. Median age was 33 years and almost half of WWH had African origin (41%). Nonbarrier contraceptive use was lower among WWH (8.5%) compared to WGP (32.1%) at study inclusion. Before and after inclusion, WWH had nearly half the nonbarrier contraceptive use of WGP, with notably lower hormonal contraception and IUD use. Initially, fewer WWH were sterilized, but 5 years after inclusion, sterilization became the preferred method among WWH. HC use increased among WWH after 2010 but decreased among WGP after 2005. IUD use increased among both groups during 1995-2021 but remained lower among WWH. Incidence of sterilizations remained stable in both groups.

CONCLUSION

Use of nonbarrier contraceptives was lower among WWH compared to WGP. For WWH, sterilization became the preferred nonbarrier method few years after study inclusion. hormonal contraception and IUD use increased among WWH after 2010 but remained lower than for WGP. Improved contraceptive counseling is recommended to support reproductive health among WWH.

Mechanism-based inactivation of cytochromes P450: implications in drug interactions and pharmacotherapy

Cytochrome P40 (CYP) enzymes dominate the metabolism of numerous endogenous and xenobiotic substances. While it is commonly believed that CYP-catalysed reactions result in the detoxication of foreign substances, these reactions can also yield reactive intermediates that can bind to cellular macromolecules to cause cytotoxicity or irreversibly inactivate CYPs that create them.Mechanism-based inactivation (MBI) produces either irreversible or quasi-irreversible inactivation and is commonly caused by CYP metabolic bioactivation to an electrophilic reactive intermediate. Many drugs that have been known to cause MBI in CYPs have been discovered as perpetrators in drug-drug interactions throughout the last 20-30 years.This review will highlight the key findings from the recent literature about the mechanisms of CYP enzyme inhibition, with a focus on the broad mechanistic elements of MBI for widely used drugs linked to the phenomenon. There will also be a brief discussion of the clinical or pharmacokinetic consequences of CYP inactivation with regard to drug interaction and toxicity risk.Gaining knowledge about the selective inactivation of CYPs by common therapeutic drugs helps with the assessment of factors that affect the systemic clearance of co-administered drugs and improves comprehension of anticipated interactions with other drugs or xenobiotics.

Drug-induced liver injury secondary to increased levonorgestrel exposure in a patient taking ritonavir

We report the first published case of a drug induced liver injury (DILI) presumed secondary to a drug-drug interaction between ritonavir and levonorgestrel progestogen-only emergency contraception (POEC). Our patient is a 25-year-old female living with human immunodeficiency virus (HIV), taking antiretroviral therapy (ART) containing tenofovir alafenamide/emtricitabine and darunavir/ritonavir. She was found to have elevated transaminases at a routine clinic appointment consistent with hepatocellular DILI. Further investigation found the most likely cause of this was a drug-drug interaction (DDI) between the ritonavir component of her ART and recent use of levonorgestrel POEC 3 days earlier. Evidence suggests that ritonavir increases levonorgestrel exposure, yet our patient received double the usual dose as per dispensing guidance at the time. We review the pharmacokinetics of ritonavir-levonorgestrel DDIs and highlight the need for consistent guidelines on this topic.

Measuring the impact of COVID-19 social distancing measures on sexual health behaviours and access to HIV and sexual and reproductive health services for people living with HIV in Botswana

Introduction

Uninterrupted access to HIV and sexual and reproductive health (SRH) services is essential, particularly in high HIV prevalence settings, to prevent unintended pregnancy and vertical HIV transmission. Understanding the challenges that COVID-19 and associated social distancing measures (SDMs) posed on health service access is imperative for future planning.

Methods

This cross-sectional study was conducted in Botswana between January-February 2021. A web-based questionnaire was disseminated on social media as part of the International Sexual Health and REproductive Health (I-SHARE) Survey. Respondents answered questions on SRH, before and during COVID-19 SDMs. Subgroup analysis and comparison of descriptive data was performed for people living with HIV (PLWH).

Results

Of 409 participants, 65 were PLWH (80% female, 20% male). During SDMs, PLWH found it more difficult to access condoms and treatment for HIV and STIs; attend HIV appointments; and maintain adherence to antiretroviral therapy. Compared to HIV-negative women, a higher proportion of women living with HIV used condoms as their primary method of contraception (54% vs. 48%), and had lower use of long-acting reversible contraception (8% vs. 14%) and dual contraception (8% vs. 16%).

Discussion

Mirroring global trends, COVID-19 disrupted HIV and SRH service access in Botswana. However, in high HIV-prevalence settings, disruption may more severely impact population health with disproportionate effects on women. Integration of HIV and SRH services could build health system capacity and resilience, reduce missed opportunities for delivering SRH services to PLWH and limit the consequences of future restrictions that may cause health system disruption.

Unintended pregnancies among HIV-positive women in sub-Saharan Africa: a scoping review protocol

BACKGROUND

Unintended pregnancies pose a severe threat to the well-being of HIV-positive women and their unborn children. Factors contributing to the high incidence of unintended pregnancies include contraceptive failure, low uptake of contraceptives, and misuse of contraceptives. Despite various contraceptive options, an increased incidence of unintended pregnancies is rampant among HIV-positive women in the region of sub-Saharan Africa. This study seeks to present evidence of unintended pregnancies among women living with HIV in sub-Saharan Africa, including those using contraceptives.

METHOD

This study entails a scoping review to survey and interrogate the literature to provide evidence for the incidence of unintended pregnancies among HIV-positive women in sub-Saharan Africa. A proposed framework by Arksey and O'Malley will guide this scoping review. Peer-reviewed articles which address the research questions will constitute the main search. Electronic databases such as EBSCOhost, Cochrane Library, World of Science, World Health Organization (WHO) library databases, Science Direct, Google Scholar PubMed, and gray literature search will be involved. Reference list from studies included will also be searched. The investigation of articles will be done employing keywords from the studies included. The inclusion and exclusion criteria will guide two separate reviewers with the screening of abstracts and full papers. To summarize the findings from this review, thematic content analysis will be done using NVivo version 11.

DISCUSSION

We expect that this review will add to the current body of knowledge on the incidence of unintended pregnancies among HIV-positive women, identify gaps for further future research, and show evidence that may contribute to strengthening the health system's regulations, guidelines, and policies that may help prevent unintended pregnancies among HIV-positive women.

SYSTEMATIC REVIEW REGISTRATION

10.17605/OSF.IO/EY3R5.

Occurrence, detection and ecotoxicity studies of selected pharmaceuticals in aqueous ecosystems- a systematic appraisal

Pharmaceutical compounds (PCs) have globally emerged as a significant group of environmental contaminants due to the constant detection of their residues in the environment. The main scope of this review is to fill the void of information on the knowledge on the African occurrence of selected PCs in environmental matrices in comparison with those outside Africa and their respective toxic actions on both aquatic and non-aquatic biota through ecotoxicity bioassays. To achieve this objective, the study focused on commonly used and detected pharmaceutical drugs (residues). Based on the conducted literature survey, Africa has the highest levels of ciprofloxacin, sulfamethoxazole, lamivudine, acetaminophen, and diclofenac while Europe has the lowest of all these PC residues in her physical environments. For ecotoxicity bioassays, the few data available are mostly on individual groups of pharmaceuticals whereas there is sparsely available data on their combined forms.

Menopause care in women living with HIV in the UK - A review

Advances in HIV care over the last 30 years have transformed a virtually fatal condition into a chronic, manageable one. Antiretroviral therapy (ART) has dramatically changed the outlook for people living with HIV so that most individuals with well controlled disease have a normal life expectancy. As result of this increase in life expectancy, one-third of women living with HIV are of menopausal age. Adding to the shift in age distribution, rates of new HIV diagnosis are increasing in the over 50-year age group, likely the result of a combination of low condom use and perception of transmission risk and in women, an increased risk of HIV acquisition due to the mucosal disruption that accompanies vaginal atrophy. Many women living with HIV are unprepared for menopause, have a high prevalence of somatic, urogenital and psychological symptomatology and low rates of menopausal hormone therapy (MHT) use. Many women experience enormous frustration shuttling between their general practitioner and HIV care provider trying to have their needs met, as few HIV physicians have training in menopause medicine and primary care physicians are wary of managing women living with HIV, in part, because of fears about potential drug-drug interactions (DDIs) between MHT and ART. Several data gaps exist with regard to the relationship between HIV and the menopause, including whether the risk of HIV transmission is increased in virally-suppressed women with vaginal atrophy, whether or not menopause amplifies the effects of HIV on cardiovascular, psychological and bone health, as well as the safety and efficacy of MHT in women living with HIV. Menopausal women living with HIV deserve high quality individualised menopause care that is tailored to their needs. More research is needed in the field of HIV and menopause, primarily on cardiovascular disease and bone health outcomes as well as symptom control, and strategies to reduce HIV acquisition, encourage testing, and maintain older women in care in order to inform optimal clinical management.

Interactions between etonogestrel-releasing contraceptive implant and 3 antiretroviral regimens

OBJECTIVES

Long-acting reversible contraceptives are effective contraceptives for women with HIV, but there are limited data on etonogestrel implant and antiretroviral therapy pharmacokinetic drug-drug interactions. We evaluated etonogestrel/antiretroviral therapy drug-drug interactions, and the effects of etonogestrel on ritonavir-boosted-atazanavir, ritonavir-boosted-lopinavir, and efavirenz pharmacokinetics.

STUDY DESIGN

We enrolled postpartum women using etonogestrel implants and receiving ritonavir-boosted-atazanavir, ritonavir-boosted-lopinavir, or efavirenz-based regimens between 2012 and 2015. Etonogestrel implants were inserted 2 to 12 weeks postpartum. We performed pharmacokinetic sampling pre-etonogestrel insertion and 6 to 7 weeks postinsertion. We measured antiretroviral concentrations pre and postetonogestrel insertion, and compared etonogestrel concentrations between antiretroviral regimens. We considered a minimum serum etonogestrel concentration of 90 pg/mL adequate for ovulation suppression.

RESULTS

We collected pharmacokinetic data for 74 postpartum women, 22 on ritonavir-boosted-atazanavir, 26 on ritonavir-boosted-lopinavir, and 26 on efavirenz. The median serum concentrations of etonogestrel when co-administered were highest with etonogestrel/ritonavir-boosted-atazanavir (604 pg/mL) and etonogestrel/ritonavir-boosted-lopinavir (428 pg/mL), and lowest with etonogestrel/efavirenz (125 pg/mL); p < 0.001. Minimum concentration (C_min) of ritonavir-boosted-atazanavir and ritonavir-boosted-lopinavir were lower after etonogestrel implant insertion, but overall exposure, predose concentrations, clearance, and half-lives were unchanged. We found no significant change in efavirenz exposure after etonogestrel insertion.

CONCLUSIONS

Unlike efavirenz, ritonavir-boosted-atazanavir and ritonavir-boosted-lopinavir were not associated with significant decreases in etonogestrel concentrations. Efavirenz was associated with a significant decrease in etonogestrel concentrations.

IMPLICATIONS

The findings demonstrate no interactions between etonogestrel and ritonavir-boosted-lopinavir or ritonavir-boosted-atazanavir, but confirm the decreased efficacy of etonogestrel with efavirenz-based antiretrovirals. This information should be used to counsel women with HIV who desire long-acting reversible contraceptives.

Low antileishmanial drug exposure in HIV-positive visceral leishmaniasis patients on antiretrovirals: an Ethiopian cohort study

Background

Despite high HIV co-infection prevalence in Ethiopian visceral leishmaniasis (VL) patients, the adequacy of antileishmanial drug exposure in this population and effect of HIV-VL co-morbidity on pharmacokinetics of antileishmanial and antiretroviral (ARV) drugs is still unknown.

Methods

HIV-VL co-infected patients received the recommended liposomal amphotericin B (LAmB) monotherapy (total dose 40 mg/kg over 24 days) or combination therapy of LAmB (total dose 30 mg/kg over 11 days) plus 28 days 100 mg/day miltefosine, with possibility to extend treatment for another cycle. Miltefosine, total amphotericin B and ARV concentrations were determined in dried blood spots or plasma using LC–MS/MS.

Results

Median (IQR) amphotericin B C_max on Day 1 was 24.6 μg/mL (17.0–34.9 μg/mL), which increased to 40.9 (25.4–53.1) and 33.2 (29.0–46.6) μg/mL on the last day of combination and monotherapy, respectively. Day 28 miltefosine concentration was 18.7 (15.4–22.5) μg/mL. Miltefosine exposure correlated with amphotericin B accumulation. ARV concentrations were generally stable during antileishmanial treatment, although efavirenz C_min was below the 1 μg/mL therapeutic target for many patients.

Conclusions

This study demonstrates that antileishmanial drug exposure was low in this cohort of HIV co-infected VL patients. Amphotericin B C_max was 2-fold lower than previously observed in non-VL patients. Miltefosine exposure in HIV-VL co-infected patients was 35% lower compared with adult VL patients in Eastern Africa, only partially explained by a 19% lower dose, possibly warranting a dose adjustment. Adequate drug exposure in these HIV-VL co-infected patients is especially important given the high proportion of relapses.

Potential risk of drug-drug interactions with hormonal contraceptives and antiretrovirals: prevalence in women living with HIV

Background

Family planning services are vital for women living with HIV (WLH); however, the use of concomitant antiretroviral therapy (ART) and hormonal contraceptives (HCs) may pose challenges due to the risk of potential drug–drug interactions (DDIs). The objectives of this study were to assess ART and HC use among WLH and quantify the frequency of potential DDIs between ART and HCs.

Methods

This was a retrospective, observational, cohort study of WLH aged 18–55 years, prescribed ART, with at least one clinic visit from January 1, 2010 to April 30, 2014. Potential DDIs between HCs and ART were assessed using the University of Liverpool HIV Drug Interactions website (www.hiv-druginteractions.org) and categorized as ‘weak potential interaction,’ ‘potential interaction,’ or ‘do not co-administer.’

Results

Overall, a contraceptive method was reported in 167 (54%) of the 309 women included in the study. Of those using contraception, 73 (43.7%) reported using HCs, which was most frequently a progestin intrauterine device (n=43), progestin injection (n=17), or combination oral contraceptive pills (n=9). Out of a total of 449 ART regimens, a potential DDI was identified in 21 of 115 (18.3%) ART–HC combinations from 19 women using ART and HCs. Atazanavir/ritonavir was the most common potentially interacting ART (10, 47.6%); for HCs, these were combination oral contraceptive pills (16, 76.2%) and progestin implants (2, 9.5%).

Conclusion

In this cohort, one-quarter of WLH on ART–HCs had a potential DDI. Future studies should investigate the impact of DDIs on unintended pregnancies, the side effects of DDIs, and the effects of HC DDIs on ART concentrations.

Confirmation of the drug-drug interaction potential between cobicistat-boosted antiretroviral regimens and hormonal contraceptives

BACKGROUND

Cobicistat (COBI), a CYP3A inhibitor, is a pharmacokinetic enhancer that increases exposures of the HIV protease inhibitors (PIs) atazanavir (ATV) and darunavir (DRV). The potential drug interaction between COBI-boosted PIs and hormonal contraceptives, which are substrates of intestinal efflux transporters and extensively metabolized by CYP enzymes, glucuronidation and sulfation, was evaluated.

METHODS

This was a Phase I, open-label, two cohort (n=18/cohort), fixed-sequence study in healthy females that evaluated the drug-drug interaction (DDI) between multiple-dose ATV+COBI or DRV+COBI and single-dose drospirenone/ethinyl estradiol (EE). DDIs were evaluated using 90% confidence intervals of the geometric least-squares mean ratios of the test (drospirenone/EE+boosted PI) versus reference (drospirenone/EE) using lack of DDI boundaries of 70-143%. Safety was assessed throughout the study.

RESULTS

29/36 participants completed the study. Relative to drospirenone/EE alone, drospirenone area under the plasma concentration versus time curve extrapolated to infinity (AUC_inf) was 1.6-fold and 2.3-fold higher, and maximum observed plasma concentration (C_max) was unaltered, upon coadministration with DRV+COBI and ATV+COBI, respectively. EE AUC_inf decreased 30% with drospirenone/EE + DRV+COBI and was unchanged with ATV+COBI + drospirenone/EE, relative to drospirenone/EE alone. Study treatments were generally well tolerated. The majority of adverse events were mild and consistent with known safety profiles of the compounds.

CONCLUSIONS

Consistent with COBI-mediated CYP3A inhibition, drospirenone exposure increased following coadministration with COBI-containing regimens, with a greater increase with ATV+COBI. Thus, clinical monitoring for drospirenone-associated hyperkalaemia is recommended with DRV+COBI and ATV+COBI should not be used with drospirenone. Lower EE exposure with DRV+COBI may be attributed to inductive effects of DRV on CYP enzymes and/or intestinal efflux transporters (that is, P-gp) involved in EE disposition.

Rational Design of a Multipurpose Bioadhesive Vaginal Film for Co-Delivery of Dapivirine and Levonorgestrel

Human immunodeficiency virus (HIV) infection and unintended pregnancy, which can lead to life-threatening complications, are two major burdens for female reproductive health. To address these pressing health issues, multipurpose prevention technologies (MPTs) are proposed to deliver two or more drugs simultaneously. MPTs could offer several benefits for users such as improved convenience, increased effectiveness, reduced cost, and decreased environmental burden. Here, we report the development, and in vitro and in vivo assessment of a bioadhesive vaginal film as a coitally-independent MPT dosage form for delivering dapivirine (DPV) and levonorgestrel (LNG) to prevent HIV infection and unintended pregnancy, respectively. After confirming the feasibility of bioadhesive film use for weekly drug delivery in vivo through colpophotography and MRI evaluation, the pharmacokinetics (PK) of DPV/LNG single entity and combination bioadhesive films was investigated in pigtailed macaques (n = 5). Both drugs from single entity or combination films were able to provide sustained drug release in vivo. The combination film showed lower local tissue clearance for DPV and exhibited significantly increased plasma concentration for LNG as compared to the single entity film. This proof-of-concept study demonstrates the ability of this novel bioadhesive film platform to deliver LNG and DPV simultaneously as an MPT product for the prevention of HIV infection and unintended pregnancy.

The Effect of Efavirenz on Estradiol Metabolism in Transgender Women

The goal of hormonal therapy in treating gender dysphoria is to maintain cross-sex hormone levels in the normal physiological range for the desired gender. Estrogen is the mainstay of hormonal therapy for male to female transgender patients. Efavirenz, a non-nucleoside reverse-transcriptase inhibitor, has been one of the most commonly prescribed antiretroviral therapies (ARTs). However, this regimen has also given rise to the most clinically significant drug-drug interactions between ARTs and hormone-based contraceptives. We discuss here three transgender HIV-positive women in whom efavirenz effected the metabolism of orally administered estradiol (and probably medroxyprogesterone).

Pharmacokinetics (PK) of ethinylestradiol/levonorgestrel co-administered with atazanavir/cobicistat

Background and objectives: Access to safe and reliable contraception in the context of ARVs is essential. This study aimed to investigate the steady-state pharmacokinetics (PK) of ethinylestradiol/levonorgestrel (EE/LNG) 30/150 μg (Microgynon^®) and atazanavir/cobicistat (ATV/COBI) 300/150 mg (Evotaz^®), co-administered in HIV negative female volunteers, and assess its safety and tolerability. Methods: This phase 1, open label, 57-day, cross over, PK study randomized participants to one of two groups: (i) group 1 received EE/LNG alone on days 1-21, EE/LNG (21 days) + ATV/COBI (14 days) in the co-administration phase (days 22-42) and ATV/COBI alone on days 43-56; (ii) group 2 followed the same sequence but started with ATV/COBI and concluding with EE/LNG. Each group underwent intensive PK sampling on days 14, 35, and 56. EE/LNG and ATV/COBI concentrations were measured using validated LC-MS/MS methods. Results: Of 14 healthy female volunteers screened, 11 attended baseline and six completed all PK phases (five withdrew secondary to side effects). Paired data were available for analysis in six subjects for EE/LNG and eight for ATV/COBI. Geometric mean ratios (GMR, with versus without ATV/COBI) and 90% confidence intervals (CI) for LNG C_max, AUC_0-24, C₂₄ were 0.83 (0.68-1.02), 0.92 (0.71-1.18), 1.01 (0.73-1.38). GMR and 90% CI for EE C_max, AUC_0-24, C₂₄ were 1.05 (0.92-1.19), 1.01 (0.83-1.22), 0.75 (0.60-0.93). No grade 3 or 4 adverse events or laboratory abnormalities were observed in the women who completed the study. Conclusions: Our findings showed no significant changes in LNG concentrations and a 25% decrease in EE C₂₄ when EE/LNG was co-administered with ATV/COBI.

No. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the availability of cited contraceptive methods in Canada.

EVIDENCE

Medline and the Cochrane Database were searched for articles in English on subjects related to contraception, sexuality, and sexual health from January 1994 to December 2015 in order to update the Canadian Contraception Consensus published February-April 2004. Relevant Canadian government publications and position papers from appropriate health and family planning organizations were also reviewed.

VALUES

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Clinical Pharmacokinetics of Systemically Administered Antileishmanial Drugs

This review describes the pharmacokinetic properties of the systemically administered antileishmanial drugs pentavalent antimony, paromomycin, pentamidine, miltefosine and amphotericin B (AMB), including their absorption, distribution, metabolism and excretion and potential drug–drug interactions. This overview provides an understanding of their clinical pharmacokinetics, which could assist in rationalising and optimising treatment regimens, especially in combining multiple antileishmanial drugs in an attempt to increase efficacy and shorten treatment duration. Pentavalent antimony pharmacokinetics are characterised by rapid renal excretion of unchanged drug and a long terminal half-life, potentially due to intracellular conversion to trivalent antimony. Pentamidine is the only antileishmanial drug metabolised by cytochrome P450 enzymes. Paromomycin is excreted by the kidneys unchanged and is eliminated fastest of all antileishmanial drugs. Miltefosine pharmacokinetics are characterized by a long terminal half-life and extensive accumulation during treatment. AMB pharmacokinetics differ per drug formulation, with a fast renal and faecal excretion of AMB deoxylate but a much slower clearance of liposomal AMB resulting in an approximately ten-fold higher exposure. AMB and pentamidine pharmacokinetics have never been evaluated in leishmaniasis patients. Studies linking exposure to effect would be required to define target exposure levels in dose optimisation but have only been performed for miltefosine. Limited research has been conducted on exposure at the drug’s site of action, such as skin exposure in cutaneous leishmaniasis patients after systemic administration. Pharmacokinetic data on special patient populations such as HIV co-infected patients are mostly lacking. More research in these areas will help improve clinical outcomes by informed dosing and combination of drugs.

The Evolving Role of Pharmacists in Transgender Health Care

Pharmacists are increasingly part of a multifaceted team providing health care to members of the often marginalized transgender (TG) community. Some pharmacists, however, may feel unprepared to care for and interact with TG individuals. By providing comprehensive, respectful, and gender-affirming support, improving physical pharmacy environments with policies and procedures, pharmacists can be trustworthy providers for TG patients. This review focuses primarily on the health issues of TG persons and the pharmacist's role in promoting health, identifying barriers to health care, and providing health care resources for TG persons. The evolution of psychiatric diagnostic criteria, access to health care, and inclusion of TG, lesbian, gay, and bisexual topics in the educational curriculum are presented. Cultural competency and diversity training that addresses gender identity and sexual orientation issues should be important interdisciplinary and interprofessional activities for all health care professional education programs. Pharmacists play a key role in the health care needs of TG persons that include appropriate laboratory monitoring, complex pharmacotherapeutic challenges, and providing unbiased gender-affirming interactions. The pharmacy's physical environment, staff training, and policies and procedures can offer unique services to TG persons.

Experience of hormone replacement therapy in postmenopausal women living with HIV

Objective

To assess the uptake of hormone replacement therapy in women living with HIV (WLHIV) in particular acceptability, response to treatment and compliance.

Study design

Retrospective review of menopausal women attending a HIV medical gynaecology clinic in a tertiary referral London Hospital between 1 January 2011 and 31 December 2016.

Main outcome measures

Patient demographics, presenting symptoms, uptake of hormone replacement therapy, type of hormone replacement therapy used and bone density assessment findings at presentation.

Results

Seventy-three HIV patients were evaluated. Of them 64 (87%) were of black ethnicity and 9 (13%) were of white ethnicity. The commonest presenting complaints were vasomotor symptoms (40/73, (55%)) followed by low mood/irritability (20/73, (27%)). When offered hormone replacement therapy, this was accepted by 28/53 (52%) in WLHIV. The commonest regimen prescribed was transdermal oestradiol/micronised progesterone. A total of 22/24 (91%) women of black ethnicity reported good symptom control if they had started hormone replacement therapy, with 4/24 (17%) subsequently discontinuing it; 3/4 (75%) of white women reported good symptom control with hormone replacement therapy, with no one discontinuing it. The commonest reason for discontinuation was irregular bleeding. Of WLHIV who had a bone density assessment, 15/25 (60%) had osteopenia while 2/25 (8%) had osteoporosis.

Conclusion

Our data show that only around 50% WLHIV accepted hormone replacement therapy when offered and a high proportion of these women discontinued it. Further research is needed to explore the reason leading to low uptake and high rates of stopping hormone replacement therapy. In addition, there is a need to increase awareness of the benefits of hormone replacement therapy in WLHIV both in the context of preventing osteoporosis and menopausal symptom management.

Impact of pharmacogenetics and pregnancy on tenofovir and emtricitabine pharmacokinetics

AIM

Treatment and prevention of mother-to-child transmission of HIV in pregnancy utilizes tenofovir (TFV) and emtricitabine (FTC) as NRTI backbone in combination with a third agent from a different class. We hypothesized that combined effect of pregnancy and pharmacogenetics significantly changes TFV and FTC pharmacokinetics (PK). Therefore, this study aims to evaluate the role of SNPs of transporters (ABCC2 and ABCC4) on TFV and FTC PK during pregnancy.

METHOD

61 pregnant or postpartum women on TFV and FTC were selected from a group of pregnant and postpartum Nigerian women and both SNPs and drug levels were evaluated.

RESULTS

Pregnancy decreases TFV plasma concentration by 26% (log₁₀ β = -0.131 [-0.228, -0.034; p = 0.009] at median [range] time-point postdose 14 [7-18.5h]). FTC concentration in individuals with ABCC2 12:g.154962860T>C TT genotype were one- to twofold higher than heterozygous (CT) and homozygous (CC) women. All other evaluated SNPs were not significant.

CONCLUSION

Pregnancy decreased TFV concentration and significant relationship was found between FTC and ABCC2 12:g.154962860T>C wild-type allele. However, the interplay between pregnancy and pharmacogenetics on TFV and FTC PK is unclear but require further evaluation.

Probing Ligand Structure-Activity Relationships in Pregnane X Receptor (PXR): Efavirenz and 8-Hydroxyefavirenz Exhibit Divergence in Activation

Efavirenz (EFV), an antiretroviral that interacts clinically with co-administered drugs via activation of the pregnane X receptor (PXR), is extensively metabolized by the cytochromes P450. We tested whether its primary metabolite, 8-hydroxyEFV (8-OHEFV) can activate PXR and potentially contribute to PXR-mediated drug-drug interactions attributed to EFV. Luciferase reporter assays revealed that despite only differing from EFV by an oxygen atom, 8-OHEFV does not activate PXR. Corroborating this, treatment with EFV for 72 h elevated the mRNA abundance of the PXR target gene, Cyp3a11, by approximately 28-fold in primary hepatocytes isolated from PXR-humanized mice, whereas treatment with 8-OHEFV did not result in a change in Cyp3A11 mRNA levels. FRET-based competitive binding assays and isothermal calorimetry demonstrated that even with the lack of ability to activate PXR, 8-OHEFV displays an affinity for PXR (IC50 12.1 μm; KD 7.9 μm) nearly identical to that of EFV (IC50 18.7 μm; KD 12.5 μm). The use of 16 EFV analogues suggest that other discreet changes to the EFV structure beyond the 8-position are well tolerated. Molecular docking simulations implicate an 8-OHEFV binding mode that may underlie its divergence in PXR activation from EFV.

Neglect of attention to reproductive health in women with HIV infection: contraceptive use and unintended pregnancies in the Swiss HIV Cohort Study

OBJECTIVES

Women with HIV infection are mainly of reproductive age and need safe, effective and affordable contraception to avoid unintended pregnancies. The aim of this study was to evaluate contraceptive use and unintended pregnancies in this population in Switzerland.

METHODS

A self-report anonymous questionnaire on contraceptive methods, adherence to them, and unintended pregnancies was completed by women included in the Swiss HIV Cohort Study (SHCS) between November 2013 and June 2014. Sociodemographic characteristics and information related to combined antiretroviral therapy and HIV disease status were obtained from the SHCS database.

RESULTS

Of 462 women included, 164 (35.5%) reported not using any contraception. Among these, 65 (39.6%) reported being sexually active, although 29 (44.6%) were not planning a pregnancy. Of 298 women using contraception, the following methods were reported: condoms, 219 (73.5%); oral hormonal contraception, 32 (10.7%); and intrauterine devices, 28 (9.4%). Among all women on contraception, 32 (10.7%) reported using more than one contraceptive method and 48 (16%) had an unintended pregnancy while on contraception (18, condoms; 16, oral contraception; four, other methods). Of these, 68.1% terminated the pregnancy and almost half (43.7%) continued using the same contraceptive method after the event.

CONCLUSIONS

Family planning needs in HIV-positive women are not fully addressed because male condoms remained the predominant reported contraceptive method, with a high rate of unintended pregnancies. It is of utmost importance to provide effective contraception such as long-acting reversible contraceptives for women living with HIV.

HIV and the menopause: A review

Effective antiretroviral therapy has resulted in a close to normal life expectancy for people living with HIV. This has led to a shift in the age distribution of women living with HIV in the UK, with one in three attending for HIV care estimated to be aged 45-56 years in 2014. The lack of experience of many HIV physicians in managing menopause, and the perceived complexity of managing menopause in women living with HIV by general practitioners means that many women are unable to access appropriate care and support. This is aggravated by the relative paucity of data on menopause in women living with HIV and conflicting results in this field, for example with regard to age of onset of menopause and symptomatology experienced. Furthermore, women living with HIV have unique considerations such as potential interactions between antiretroviral therapy and menopause hormone therapy (previously called hormone replacement therapy) and other physiological concerns such as a multifactorial propensity towards decreased bone mineral density and potentially increased cardiovascular risk. On the whole, menopause hormone therapy is probably underutilised in this group of women due to perceived concerns around drug-drug interactions, as well as fears shared with women in the general population about menopause hormone therapy. Menopausal women should be given adequate information on symptomatology, lifestyle modification and treatment options including menopause hormone therapy. Furthermore, a holistic approach which considers the increased burden of poor mental health in this population is essential.

A safety evaluation of raltegravir for the treatment of HIV

INTRODUCTION

Raltegravir (RAL) was the first commercialized agent from a new drug class with an innovative target, the integrase. Since its introduction in clinical practice RAL has become widely used for the treatment of HIV-1 infected patients. A decade after its approval, this article reviews key evidence from RAL with a special interest on safety outcomes. Areas covered: Pharmacologic, safety and efficacy data of RAL from clinical trials and post-commercialization published reports are hereby summarized after a literature review including PubMed search, relating proceedings and abstracts from relevant international HIV conferences, assessment reports from European and United States regulatory agencies and treatment guidelines (World Health Organization, United States Department of Health and Human Services and European AIDS Clinical Society), up to October 2017. Most frequent search terms were 'raltegravir', 'safety', 'adverse events', 'efficacy' and 'integrase-inhibitors'. Expert opinion: Despite the arrival of new integrase strand transfer inhibitors (INSTIs) with advantages in terms of dosing convenience (elvitegravir, ELV) and higher genetic barrier (dolutegravir, DTG), RAL has stood the test of time and its overall favourable safety profile, without significant appearance of unexpected adverse events, vouch for its relevance in the antiretroviral armamentarium.

Current and future contraceptive options for women living with HIV

INTRODUCTION

Among women living with HIV, half of the pregnancies are unintended. Effective contraception can prevent unintended pregnancies and consequently reduce maternal mortality and perinatal transmission of HIV. While contraceptive options available for all women also apply to women living with HIV, specific considerations exist to the use of contraception by women living with HIV.

AREAS COVERED

First, general principles guiding the use of contraception among women living with HIV are discussed, such as choice, method mix, relative effectiveness, and drug-drug interactions. Second, a detailed discussion of each contraceptive method and issues surrounding the use of that method, such as drug-drug interactions, follows. Third, future contraceptive options in advanced development for use by women or men are briefly discussed.

EXPERT OPINION

Contraceptive methods available to all women should also be accessible to women living with HIV. When the relative effectiveness of a contraceptive method is reduced, for example due to drug-drug interactions with antiretrovirals, the method should still be made available to women living with HIV with the appropriate information sharing and counseling. Greater research on various aspects of contraceptive use by women living with HIV and more comprehensive testing of co-administration of hormonal contraceptives and common medications used by these women are warranted.

Drug-Drug Interactions, Effectiveness, and Safety of Hormonal Contraceptives in Women Living with HIV

Family planning options, including hormonal contraceptives, are essential for improving reproductive health among the more than 17 million women living with HIV worldwide. For these women, prevention of unintended pregnancy decreases maternal and child mortality, as well as reduces the risk of perinatal HIV transmission. Similarly, treatment of HIV with antiretroviral therapy (ART) is essential for reducing morbidity and mortality among HIV-positive individuals, as well as preventing HIV transmission between sexual partners or from mother to child. Importantly, despite the benefits of hormonal contraceptives, barriers to effective family planning methods exist for HIV-positive women. Specifically, drug-drug interactions can occur between some antiretroviral medications and some hormonal contraceptives, which may influence both contraceptive efficacy and tolerability. In addition, safety concerns have been raised about the impact of hormonal contraceptives on HIV disease progression, tolerability, and the risk of female-to-male HIV transmission. This review article summarizes the potential for drug-drug interactions, tolerability, and contraceptive effectiveness when hormonal contraceptives are combined with ART. In addition, the evidence surrounding the influence of hormonal contraceptives on HIV transmission and HIV disease progression in women living with HIV are summarized.

Strengths, weaknesses, opportunities and challenges for long acting injectable therapies: Insights for applications in HIV therapy

Advances in solid drug nanoparticle technologies have resulted in a number of long-acting (LA) formulations with the potential for once monthly or longer administration. Such formulations offer great utility for chronic diseases, particularly when a lack of medication compliance may be detrimental to treatment response. Two such formulations are in clinical development for HIV but the concept of LA delivery has its origins in indications such as schizophrenia and contraception. Many terms have been utilised to describe the LA approach and standardisation would be beneficial. Ultimately, definitions will depend upon specific indications and routes of delivery, but for HIV we propose benchmarks that reflect perceived clinical benefits and available data on patient attitudes. Specifically, we propose dosing intervals of ≥1week, ≥1month or ≥6months, for oral, injectable or implantable strategies, respectively. This review focuses upon the critical importance of potency in achieving the LA outcome for injectable formulations and explores established and emerging technologies that have been employed across indications. Key technological challenges such as the need for consistency and ease of administration for drug combinations, are also discussed. Finally, the review explores the gaps in knowledge regarding the pharmacology of drug release from particulate-based LA injectable suspensions. A number of hypotheses are discussed based upon available data relating to local drug metabolism, active transport systems, the lymphatics, macrophages and patient-specific factors. Greater knowledge of the mechanisms that underpin drug release and protracted exposure will help facilitate further development of this strategy to achieve the promising clinical benefits.

Transgender women, hormonal therapy and HIV treatment: a comprehensive review of the literature and recommendations for best practices

INTRODUCTION

Studies have shown that transgender women (TGW) are disproportionately affected by HIV, with an estimated HIV prevalence of 19.1% among TGW worldwide. After receiving a diagnosis, HIV-positive TGW have challenges accessing effective HIV treatment, as demonstrated by lower rates of virologic suppression and higher HIV-related mortality. These adverse HIV outcomes have been attributed to the multiple sociocultural and structural barriers that negatively affect their engagement within the HIV care continuum. Guidelines for feminizing hormonal therapy among TGW recommend combinations of oestrogens and androgen blockers. Pharmacokinetic studies have shown that certain antiretroviral therapy (ART) agents, such as protease inhibitors (PIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and cobicistat, interact with ethinyl estradiol, the key oestrogen component of oral contraceptives (OCPs). The goal of this article is to provide an overview of hormonal regimens used by TGW, to summarize the known drug-drug interactions (DDIs) between feminizing hormonal regimens and ART, and to provide clinical care recommendations.

METHODS

The authors identified English language articles examining DDIs between oestrogen therapy, androgen blockers and ART published between 1995 and 2015 using PubMed, Cumulative Index to Nursing and Allied Health Literature and EBSCOhost.

RESULTS AND DISCUSSION

Published articles predominantly addressed interactions between ethinyl estradiol and NNRTIs and PIs. No studies examined interactions between ART and the types and doses of oestrogens found in feminizing regimens. DDIs that may have the potential to result in loss of virologic suppression included ethinyl estradiol and amprenavir, unboosted fosamprenavir and stavudine. No clinically significant DDIs were noted with other anti-retroviral agents or androgen blockers.

CONCLUSIONS

There are insufficient data to address DDIs between ART and feminizing hormone regimens used by TGW. There is an urgent need for further research in this area, specifically pharmacokinetic studies to study the direction and degree of interactions between oral, injectable and transdermal estradiol and ART. Clinicians need to be vigilant about possible interactions and monitor hormone levels if concerns arise. More research is also needed on the provision of hormone therapy and gender-affirming care on the long-term health outcomes of HIV-positive TGW.

Toward Earlier Inclusion of Pregnant and Postpartum Women in Tuberculosis Drug Trials: Consensus Statements From an International Expert Panel

Tuberculosis is a major cause of morbidity and mortality in women of childbearing age (15-44 years). Despite increased tuberculosis risk during pregnancy, optimal clinical treatment remains unclear: safety, tolerability, and pharmacokinetic data for many tuberculosis drugs are lacking, and trials of promising new tuberculosis drugs exclude pregnant women. To advance inclusion of pregnant and postpartum women in tuberculosis drug trials, the US National Institutes of Health convened an international expert panel. Discussions generated consensus statements (>75% agreement among panelists) identifying high-priority research areas during pregnancy, including: (1) preventing progression of latent tuberculosis infection, especially in women coinfected with human immunodeficiency virus; (2) evaluating new agents/regimens for treatment of multidrug-resistant tuberculosis; and (3) evaluating safety, tolerability and pharmacokinetics of tuberculosis drugs already in use during pregnancy and postpartum. Incorporating pregnant women into clinical trials would extend evidence-based tuberculosis prevention and treatment standards to this special population.

Sexually transmitted infections and use of contraceptives in women living with HIV in Denmark - the SHADE cohort

Background

No Danish guidelines for screening of sexually transmitted infections (STIs) in women living with HIV (WLWH) exist, except for annual syphilis testing. Drug-drug interaction between hormonal contraceptives and some types of highly active antiretroviral therapy (HAART) occurs. We assessed prevalence of STIs, contraceptive choices and predictors of condom use in a cohort of WLWH in Denmark.

Methods

WLWH consecutively enrolled during their outpatient visits from 2011 to 2012. Gynaecological examination and an interview were performed at entry and 6-month follow-up. Inclusion criteria were HIV-1 infection and ≥ 18 years of age. Exclusion criteria were pregnancy, alcohol- or drug abuse impeding adherence to the protocol. At entry, participants were tested (and where appropriate, treated according to guidelines) for Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis, and herpes simplex (HSV-1 and HSV-2). At follow-up, predictors of condom use were estimated in sexually active WLWH.

Results

In total, 334 of the 1,392 eligible WLWH in Denmark were included (median age and HIV duration: 42.5 and 11.3 years). Chlamydia trachomatis was present in four individuals (1 %), and six (2 %) tested positive for HSV-2 by PCR. None were positive for Neisseria gonorrhoeae, HSV-1 or had active syphilis. At follow-up, 252 (76 %) participated; 168 (70 %) were sexually active. Contraceptives were used by 124 (75 %); condoms were preferred (62 %). Having an HIV-negative partner predicted condom use (adjusted OR 3.89 (95 %CI 1.49-10.11)). In the group of participants of reproductive age without pregnancy desires 13 % used no birth-control. Possible drug-drug interaction between hormonal contraceptives and HAART was found in 13/14 WLWH receiving both kinds of medication.

Conclusion

The prevalence of STIs in WLWH in Denmark was low. The need for annual STI screening is questionable. Condoms were preferred contraceptives, especially in WLWH with an HIV-negative partner. In this cohort, 13 % of WLWH of reproductive age were at risk of unintended pregnancies due to lack of birth-control. Finally, in the subgroup of WLWH receiving both hormonal contraceptives and HAART possible drug-drug interactions could occur.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1412-7) contains supplementary material, which is available to authorized users.

Dolutegravir - a review of the pharmacology, efficacy, and safety in the treatment of HIV

Dolutegravir is the newest integrase strand transfer inhibitor to be approved for the treatment of human immunodeficiency virus (HIV) infection. Dolutegravir is equivalent or superior to existing treatment regimens in both treatment-naïve and treatment-experienced patients including those with previous raltegravir or elvitegravir failure. The consistent efficacy coupled with excellent tolerability and infrequent drug–drug interactions makes the co-formulation of dolutegravir with two nucleotide reverse-transcriptase inhibitors an attractive treatment option. This review summarizes the pharmacokinetics, adverse event profile, and efficacy of dolutegravir in the treatment of HIV.