A Combination of Amino Acid Mutations Leads to Resistance to Multiple Nucleoside Analogs in Reverse Transcriptases from HIV-1 Subtypes B and C.

Resistance to anti-HIV drugs has been a problem from the beginning of antiviral drug treatments. The recent expansion of combination antiretroviral therapy worldwide has led to an increase in resistance to antiretrovirals; understanding the mechanisms of resistance is increasingly important. In this study, we analyzed reverse transcriptase (RT) variants based on sequences derived from an individual who had low-level rebound viremia while undergoing therapy with abacavir, azidothymidine (AZT) (zidovudine), and (-)-l-2',3'-dideoxy-3'-thiacytidine (3TC) (lamivudine). The RT had mutations at positions 64, 67, 70, 184, and 219 and a threonine insertion after amino acid 69 in RT. The virus remained partially susceptible to the nucleoside RT inhibitor (NRTI) regimen. We show how these mutations affect the ability of NRTIs to inhibit DNA synthesis by RT. The presence of the inserted threonine reduced the susceptibility of the RT mutant to inhibition by tenofovir.

High prevalence of gastrointestinal manifestations among Cytomegalovirus end-organ disease in the combination antiretroviral era.

BACKGROUND: Cytomegalovirus (CMV) end-organ disease (EOD) continues to pose a significant risk to patients with advanced HIV disease despite decreased incidence with combination anti-retroviral therapy (ART) and lower mortality with effective anti-CMV therapy. Subclinical CMV shedding may also contribute to ongoing inflammation and non-infectious comorbidities. METHODS: We examined the occurrence of CMV EOD and CMV shedding in a cohort of patients participating in a prospective observational study of severely immunosuppressed (CD4 ≤100 cells/µl), ART-naïve, HIV-1 infected adult participants. RESULTS: We studied 206 participants, of whom 193 (93.7%) were CMV IgG positive. Twenty-five participants (12.1%) developed confirmed CMV EOD. At baseline, 47 (22.8%) had CMV viremia detectable by PCR in the absence of clinical disease (CMV viremia). The remaining 134 (65%) had neither CMV EOD nor CMV viremia detected at baseline. Five participants with CMV EOD (2.4% of total cohort, 20% of CMV EOD) met AIDS Clinical Trials Group criteria for CMV immune reconstitution inflammatory syndrome (IRIS). Only one-third of CMV EOD patients had retinitis, while two-thirds presented with histologically confirmed gastrointestinal illness. CMV viremia was associated with higher percentages of activated CD8+ T cells even after HIV suppression. CONCLUSION: The manifestations of CMV EOD in advanced HIV disease before and after initiation of ART may be more diverse than previously described, with high incidence of gastrointestinal illness. Recognition and treatment of unusual clinical presentations of CMV infection remains important in reducing morbidity and mortality from HIV co-infections.

Perspectives of US women participating in a candidate PrEP study: adherence, acceptability and future use intentions.

INTRODUCTION: Limited data exist on acceptability of candidate pre-exposure prophylaxis (PrEP) regimens among US women. We evaluated PrEP experiences, attitudes and future use intentions among sexually active women who completed the US-based HIV Prevention Trials Network 069/AIDS Clinical Trials Group 5305 study. METHODS: Women participated in the study between March 2013 and November 2015. We analysed computer-assisted self-interview (CASI) surveys among 130 women and conducted in-depth interviews among a subset of 26 women from three sites. Interviews were conducted in mid/late-2015. RESULTS: Most women (57%) reported very good/excellent PrEP adherence on CASI, although 21% acknowledged over-reporting adherence at least some of the time. Commitment to preventing HIV infection, a sense of ownership of the study, and keeping pills stored in a visible location facilitated adherence. Adherence barriers included "simply forgetting" and being away from home. Most women interviewed did not intend to use PrEP in the future because of lack of perceived need due to their own (as opposed to their partners') low-risk behaviour and concerns about affordability - but not because of side effects or other characteristics of the regimens. DISCUSSION: Improving HIV prevention options for US women will require access to affordable PrEP as well as expanding women's understanding of relationship- and community-level factors that increase their risk of acquiring HIV.

Complex decisions: correlates of injectable contraceptive discontinuation following HIV-1 seroconversion in an HIV prevention trial.

Contraceptive adherence during acute and recent HIV-1 infection is important to maternal and child health given the elevated risk of vertical HIV-1 transmission and additional complications of pregnancy. Injectable contraception (IC) is the most common non-barrier modern contraception method used in sub-Saharan Africa (SSA). Adherence to IC after HIV-1 seroconversion is not well understood. We examined factors associated with IC discontinuation among women in SSA diagnosed with HIV-1 infection while participating in a clinical trial of biomedical HIV-1 prevention. After diagnosis with HIV-1 infection in the VOICE trial, 255 women from South Africa, Uganda, and Zimbabwe enrolled in a longitudinal observational study (MTN-015). Contraceptive method was assessed at MTN-015 baseline and at 3, 12, and 24 months post-seroconversion. Correlates of IC discontinuation were examined by Cox proportional hazard modeling. IC use was reported at baseline by 78% of women enrolled (198/255), of which 92% (182/198) completed at least one follow-up visit. Two-thirds of women (66%, 121/182) continued on IC during the follow-up period (median 24 months). Lower rates of IC discontinuation were observed in women who reported having had at least one child (HR 0.39, 95% CI 0.20-0.82) or earning a personal income (HR 0.51, 95% CI 0.30-0.87) at baseline. These findings suggest that many women with HIV-1 infection face complex decision-making regarding family planning in the years that follow seroconversion and highlight that some women may discontinue IC use despite on-site provision of family planning services. Understanding the broader context of family planning choices in recently seroconverted women may be key to more effective linkages between family planning services and HIV-1 testing and care.

Two-drug regimens for treatment of naïve HIV-1 infection and as maintenance therapy.

As people live longer with HIV infection, there has been a resurgence of interest in challenging the use of three-drug therapy, including two nucleoside reverse transcriptase inhibitors plus a third drug, as initial treatment of HIV infection or for maintenance therapy in virologically suppressed individuals. Although initial studies showed poor efficacy and/or substantial toxicity, more recent regimens have held greater promise. The SWORD-1 and -2 studies were pivotal trials of dolutegravir plus rilpivirine as maintenance therapy in virologically suppressed patients with no history of drug resistance, leading to the US Food and Drug Administration's approval of the regimen as a small, single tablet. More recently, the GEMINI-1 and -2 studies demonstrated that dolutegravir plus lamivudine is as safe and effective as the same regimen when combined with tenofovir disoproxil fumarate in treatment-naïve individuals. Together, these and other studies of novel two-drug regimens offer the potential for improved tolerability and simplicity, as well as a reduction in cost. We will review historical and recent trials of two-drug therapy for the treatment of HIV-1 infection.

Next generation fixed dose combination pharmacotherapies for treating HIV.

INTRODUCTION: Treatment options for patients with HIV-1 infection have grown over the past two decades to include multiple fixed-dose combination pharmacotherapies that have greatly simplified administration of antiretroviral therapy (ART) for both patients and providers. Effective virologic control can often be achieved with once-daily use of a single-tablet regimen. Over the past three years, ART drug development has focused on the next generation of fixed-dose combinations for initial and maintenance therapy with improved efficacy, safety and tolerability. AREAS COVERED: This review covers pre-clinical and clinical data searched through PubMed and presented at major conferences through November 2017. EXPERT OPINION: Currently available single-tablet regimens have clinical limitations related to adverse event profiles, drug-drug and drug-food interactions and variable barriers to resistance. Anticipated advances in ART fixed-dose combinations promise combinations of current multiple tablet regimens into single tablets, as well as combinations with novel drugs with improved safety and tolerability. The traditional dogma of effective ART containing at least three active antiretroviral drugs is being challenged by promising data to support efficacy of certain regimens containing two drugs. Implementation of next generation ART will bring to light issues of clinical preference and cost-effectiveness as patents of existing drugs expire and more generic formulations become available.

Provider perspectives on barriers to reproductive health services for HIV-infected clients in Central Malawi.

Despite widespread availability of Depo-Provera in HIV clinics in Malawi, coverage of family planning (FP) remains low. We sought to understand provider perspectives about the challenges of providing reproductive health services to HIV-infected clients in antiretroviral therapy (ART) clinics in Central Malawi by conducting surveys and semi structured in-depth interviews with 31 ART providers across 16 clinical sites. Additionally, site surveys were performed to assess contraceptive resources. Major barriers to the provision of FP in ART clinics were inadequate staff in the facility, shortage of trained providers, limited time to counsel on FP, and lack of private space for the provision of FP services. These barriers limit the direct delivery of FP in ART clinics. Strategies to integrate FP with HIV/ART services and task shifting FP service provision to non-ART providers should be explored in Malawi as a means to improve coverage of services to HIV-infected clients.