Emergence of Drug Resistance in the Swiss HIV Cohort Study Under Potent Antiretroviral Therapy Is Observed in Socially Disadvantaged Patients

Modeling Drug Resistance Emergence and Transmission in HIV-1 in the UK

A deeper understanding of HIV-1 transmission and drug resistance mechanisms can lead to improvements in current treatment policies. However, the rates at which HIV-1 drug resistance mutations (DRMs) are acquired and which transmitted DRMs persist are multi-factorial and vary considerably between different mutations. We develop a method for the estimation of drug resistance acquisition and transmission patterns. The method uses maximum likelihood ancestral character reconstruction informed by treatment roll-out dates and allows for the analysis of very large datasets. We apply our method to transmission trees reconstructed on the data obtained from the UK HIV Drug Resistance Database to make predictions for known DRMs. Our results show important differences between DRMs, in particular between polymorphic and non-polymorphic DRMs and between the B and C subtypes. Our estimates of reversion times, based on a very large number of sequences, are compatible but more accurate than those already available in the literature, with narrower confidence intervals. We consistently find that large resistance clusters are associated with polymorphic DRMs and DRMs with long loss times, which require special surveillance. As in other high-income countries (e.g., Switzerland), the prevalence of sequences with DRMs is decreasing, but among these, the fraction of transmitted resistance is clearly increasing compared to the fraction of acquired resistance mutations. All this indicates that efforts to monitor these mutations and the emergence of resistance clusters in the population must be maintained in the long term.

The Role of Human Immunodeficiency Virus (HIV) Asymptomatic Status When Starting Antiretroviral Therapy on Adherence and Treatment Outcomes and Implications for Test and Treat: The Swiss HIV Cohort Study

BACKGROUND

Since the advent of universal test-and-treat , more people living with human immunodeficiency virus (PLHIV) initiating antiretroviral therapy (ART) are asymptomatic with a preserved immune system. We explored the impact of asymptomatic status on adherence and clinical outcomes.

METHODS

PLHIV registered in the Swiss HIV Cohort Study (SHCS) between 2003 and 2018 were included. We defined asymptomatic as Centers for Disease Control and Prevention stage A within 30 days of starting ART, non-adherence as any self-reported missed doses and viral failure as two consecutive viral load>50 copies/mL after >24 weeks on ART. Using logistic regression models, we measured variables associated with asymptomatic status and adherence and Cox proportional hazard models to assess association between symptom status and viral failure.

RESULTS

Of 7131 PLHIV, 76% started ART when asymptomatic and 1478 (22%) experienced viral failure after a median of 1.9 years (interquartile range, 1.1-4.2). In multivariable models, asymptomatic PLHIV were more likely to be younger, men who have sex with men, better educated, have unprotected sex, have a HIV-positive partner, have a lower viral load, and have started ART more recently. Asymptomatic status was not associated with nonadherence (odds ratio, 1.03 [95% confidence interval {CI}, .93-1.15]). Asymptomatic PLHIV were at a decreased risk of viral failure (adjusted hazard ratio, 0.87 [95% CI, .76-1.00]) and less likely to develop resistance (14% vs 27%, P < .001) than symptomatic PLHIV.

CONCLUSIONS

Despite concerns regarding lack of readiness, our study found no evidence of adherence issues or worse clinical outcomes in asymptomatic PLHIV starting ART.

Predictors of virological failure and time to viral suppression of first line integrase inhibitor based antiretroviral treatment

Background

Integrase strand transfer inhibitors (InSTIs) are recommended for first-line treatment of persons with human immunodeficiency virus (HIV). We identified risk factors, including baseline minor InSTI resistance mutations, for treatment failure of InSTI-based regimens.

Methods

We studied time-to-treatment failure and time to viral suppression among 1419 drug-naive patients in the Swiss HIV Cohort Study. We performed Cox regression models adjusted for demographic factors, baseline HIV RNA/CD4 cell counts, AIDS-defining events, and the type of InSTI. In 646 patients with a baseline genotypic resistance test of the integrase, we studied the impact of minor integrase resistance mutations.

Results

We observed 121 virological failures during 18 447 person-years of follow-up. A baseline viral load ≥100 000 copies/mL (multivariable hazard ratio [mHR], 2.2; 95% confidence interval [CI], 1.3–3.6) and an AIDS-defining event (mHR, 1.8; 95% CI. 1.1–3.0) were associated with treatment failure. CD4 counts between 200 and 500 cells/µL (mHR, 0.5; 95% CI, .3–.8) and >500 cells/µL (mHR, 0.4; 95% CI, .2–.7) were protective. Time to suppression was shorter in lower viral load strata (mHR, 0.7; 95% CI, .6–.8) and in dolutegravir-based therapy (mHR, 1.2; 95% CI, 1.0–1.4). Minor resistance mutations were found at baseline in 104 of 646 (16%) patients with no effect on treatment outcome.

Conclusions

Factors associated with treatment failure on InSTI-based first-line regimen remained similar to those of older treatments, in particular high viral load and low CD4 counts.

Marked decrease in acquired resistance to antiretrovirals in latest years in Italy

OBJECTIVES

The aim of this study was to evaluate acquired drug resistance in Italy in the 2009-2018 period.

METHODS

We analysed 3094 patients from the Italian ARCA database who had failed antiretroviral treatment and who had received a genotypic test after 6 months of treatment. Drug resistance mutations were identified using International AIDS Society (IAS)-USA tables and the Stanford HIVdb algorithm. The global burden of acquired resistance was calculated among all subjects with antiretroviral failure. Time trends and correlates of resistance were analysed using standard statistical tests.

RESULTS

Patients of non-European origin and non-B subtypes increased significantly from 11.5% (103/896) to 19.2% (33/172) and from 13.1% (141/1079) to 23.8% (53/223), respectively, over time. Overall, 14.5% (448/3094), 12.1% (374/3094) and 37.8% (1169/3094) of patients failed first, second and later lines, respectively. According to both IAS and HIVdb, in the study period resistance to any class, nucleoside reverse inhibitor, non-nucleoside reverse inhibitor, and protease inhibitors (PIs) declined significantly. Integrase strand transfer inhibitor (INSTI) resistance declined significantly from 31% (36/116) to 20.8% (41/197) according to HIVdb but not to IAS. Divergent data were highlighted regarding the proportion of non-European patients carrying any, PI and INSTI resistance using IAS tables compared with the Stanford HIVdb algorithm, as the former failed to detect a decrease in resistance while the latter indicates a reduction of 1.6-, 5- and 1.8-fold resistance for such drug classes. In the multivariate analysis, the risk of resistance increased in patients with a larger number of treatment lines and higher viraemia and decreased in those starting therapy in the last biennium of the study.

DISCUSSION

A marked reduction in drug resistance was observed over 10 years, compatible with higher genetic barrier and potency of new antiretrovirals. Nonetheless, concerns remain for subjects with non-B subtypes when using mutation lists instead of interpretation systems because of the extensive polymorphism of the protease region.

Impact of Pharmacist-Driven Antiretroviral Stewardship and Transitions of Care Interventions on Persons With Human Immunodeficiency Virus

Background

Persons with human immunodeficiency virus (HIV) experience high rates of medication-related errors when admitted to the inpatient setting. Data are lacking on the impact of a combined antiretroviral (ARV) stewardship and transitions of care (TOC) program. We investigated the impact of a pharmacist-driven ARV stewardship and TOC program in persons with HIV.

Methods

This was a retrospective, quasi-experimental analysis evaluating the impact of an HIV-trained clinical pharmacist on hospitalized persons with HIV. Patients included in the study were adults following up, or planning to follow up, at the University of Illinois (UI) outpatient clinics for HIV care and admitted to the University of Illinois Hospital. Data were collected between July 1, 2017 and December 31, 2017 for the preimplementation phase and between July 1, 2018 and December 31, 2018 for the postimplementation phase. Primary and secondary endpoints included medication error rates related to antiretroviral therapy (ART) and opportunistic infection (OI) medications, all-cause readmission rates, medication access at time of hospital discharge, and linkage to care rates.

Results

A total of 128 patients were included in the study: 60 in the preimplementation phase and 68 in the postimplementation phase. After the implementation of this program, medication error rates associated with ART and OI medications decreased from 17% (10 of 60) to 6% (4 of 68) (P = .051), 30-day all-cause readmission rates decreased significantly from 27% (16 of 60) to 12% (8 of 68) (P = .03), and linkage to care rates increased significantly from 78% (46 of 59) to 92% (61 of 66) (P = .02).

Conclusions

A pharmacist-led ARV stewardship and TOC program improved overall care of persons with HIV through reduction in medication error rates, all-cause readmission rates, and an improvement in linkage to care rates.

Prevalence of pretreatment and acquired HIV-1 mutations associated with resistance to lamivudine or rilpivirine: a systematic review

BACKGROUND

Pretreatment and acquired drug resistance mutations (DRMs) can limit antiretroviral therapy effectiveness.

METHODS

We review prevalence of DRMs with resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), focusing on lamivudine and rilpivirine, from 127 articles with >100,000 individuals with HIV-1 infection.

RESULTS

Estimated global prevalence of pretreatment resistance to any NRTI was 4% and to any NNRTI was 6%. Most prevalent DRMs resistant to lamivudine or rilpivirine were at positions E138 (4%), V179 (1%) and M184 (1%). Estimated acquired DRM prevalence was 58% for any NRTIs and 67% for any NNRTIs, most frequently at positions M184 (58%) and Y181 (21%).

CONCLUSIONS

This review suggests low risk of lamivudine- or rilpivirine-resistant mutations in treatment-naive, HIV-1-infected individuals.

The same lesson over and over: drugs alone will not get us to 90--90--90

: Addressing social determinants of health (SDH) has far greater potential to improve the real-world effectiveness of HIV treatment than expensive, incremental changes in antiretroviral therapy. The ADVANCE study demonstrates that SDH is more impactful than medication regimen on health outcomes. Younger patients and unemployed patients experience heightened precarity, which can have pervasive effects on adherence and suppression. Enhanced adherence counselling can help socioeconomically precarious patients maintain suppression, but in order to improve treatment effectiveness and population health, we should move beyond the short-term solution of helping patients 'cope' with insecurity toward tackling the underlying factors that lead to precarity. Data on intention-to-treat populations are critical to this effort, yet medical researchers and publications continue to obscure the influence of SDH by focusing on per-protocol populations.

The arc of HIV epidemics in sub-Saharan Africa: new challenges with concentrating epidemics in the era of 90-90-90

PURPOSE OF REVIEW

The aim of this review is to examine the emerging results from the HIV universal test and treat (UTT) cluster-randomized trials in sub-Saharan Africa, discuss how expanding access to HIV clinical services is likely to reshape the arc of HIV epidemics, and consider implications for HIV prevention and control strategies in the coming decade.

RECENT FINDINGS

The effect of universal HIV testing followed by immediate antiretroviral treatment (ART) on community-level HIV incidence remains unclear upon completion of five randomized trials. Only two of the four trials that measured HIV incidence found significant reductions in community-level incidence. Even in these trials, HIV incidence remained above levels required for epidemic control (≤1 case per 1000 person-years) despite high levels of ART coverage and viral suppression. These findings may indicate that community-delivered HIV services are not reaching the high-frequency transmitters who sustain HIV epidemics and are likely members of marginalized or hard to engage core groups.

SUMMARY

With expanded access to HIV services in sub-Saharan Africa, HIV epidemics are transitioning from hyperendemic to declining/endemic epidemic phases, characterized increasingly by the reconcentration of HIV in marginalized or hard to engage core groups. To move toward epidemic control, novel HIV service delivery models and technologies are needed to engage those who continue to drive HIV incidence in this new epidemic phase.