First-line HIV treatment outcomes following the introduction of integrase inhibitors in UK guidelines

Drug-Drug Interactions Between HIV Antivirals and Concomitant Drugs in HIV Patients: What We Know and What We Need to Know

Highly active antiretroviral therapy has led to a significant increase in the life expectancy of people living with HIV. The trade-off is that HIV-infected patients often suffer from comorbidities that require additional treatment, increasing the risk of Drug-Drug Interactions (DDIs), the clinical relevance of which has often not been determined during registration trials of the drugs involved. Therefore, it is important to identify potential clinically relevant DDIs in order to establish the most appropriate therapeutic approaches. This review aims to summarize and analyze data from studies published over the last two decades on DDI-related adverse clinical outcomes involving anti-HIV drugs and those used to treat comorbidities. Several studies have examined the pharmacokinetics and tolerability of different drug combinations. Protease inhibitors, followed by nonnucleoside reverse transcriptase inhibitors and integrase inhibitors have been recognized as the main players in DDIs with antivirals used to control co-infection, such as Hepatitis C virus, or with drugs commonly used to treat HIV comorbidities, such as lipid-lowering agents, proton pump inhibitors and anticancer drugs. However, the studies do not seem to be consistent with regard to sample size and follow-up, the drugs involved, or the results obtained. It should be noted that most of the available studies were conducted in healthy volunteers without being replicated in patients. This hampered the assessment of the clinical burden of DDIs and, consequently, the optimal pharmacological management of people living with HIV.

Factors Associated with Time to Initial Antiretroviral Therapy Discontinuation in the DC Cohort

When an initial antiretroviral therapy (ART) regimen is effective and well-tolerated, it can be maintained for years as long as the patient adheres. Prior research has revealed that shorter initial ART duration is associated with regimen type, female sex, injection drug use as the HIV transmission category, and lower baseline CD4 count. We examined potential factors associated with initial regimen discontinuation among a subset of newly diagnosed virally unsuppressed PWH in the DC Cohort, an ongoing prospective observation study that uses electronic health record data from clinic sites to collect relevant information, including demographic and clinical information. Participants were excluded from the analysis if they had less than 6 months of follow-up and were virally suppressed at enrollment. There were 479 individuals included in the study. The median age of participants was 33.9 years [interquartile range (IQR) 26-43.9]. The sample was predominantly male (79.1%) and of Black race (70.8%). Over half of the study participants (56.4%) attended community-based clinic sites. The median time to the discontinuation of initial ART was 2.7 years [95% confidence interval (CI): 2.3, 3.4]. Females had a shorter time to ART discontinuation [adjusted hazard ratio (aHR) 1.55, 95% CI: 1.14, 2.11] as did individuals who started on a protease inhibitor-based regimen versus integrase strand transfer inhibitors (aHR 1.87, 95% CI: 1.34, 2.61) and those receiving HIV care at a community-based site (aHR 1.46, 95% CI: 1.11,1.93). Although limited by lack of reason for discontinuation, we demonstrated that ART-naïve women, community clinic attendees, and patients starting on PIs had a shorter duration of initial ART. More anticipatory guidance may be needed to help patients stay on their initial therapy and manage the side effects or to be flexible in trying different regimens.

Effectiveness of integrase strand transfer inhibitors among treatment-naive people living with HIV/AIDS in Guangdong, China: A real-world, retrospective cohort study

Integrase strand transfer inhibitors (INSTIs) in anti-retroviral therapy (ART) have been recommended by the World Health Organization for their higher efficacy, favorable safety and tolerability. However, the clinical evidence supporting switching to INSTI-containing regimens in low-and-middle-income countries (LMICs) is limited, as few patients have access to these regimens. We aimed to assess the effectiveness of INSTI-containing regimens in real-world settings in China compared to government-provided free ART. We compared the short-term (first 4 mo following ART initiation) and long-term (1 year after ART initiation) effectiveness between INSTI-containing regimens and free ART drugs provided by the Chinese government in 4 dimensions: viral suppression status, immune response, liver and kidney function, and AIDS-related diseases. We obtained data from electronic medical records in the National Infectious Disease Surveillance System. To control baseline confounders, we used propensity score matching (PSM), calculated using logistic regression including socio-demographic and baseline factors. Among 12,836 patients from 2012 to 2019, 673 (5.2%) used INSTI-containing regimens. Patients with INSTI-containing regimens were matched to those with free drugs (644 vs 644). For short-term effectiveness, patients initiating INSTI-containing regimens were more likely to achieve viral suppression (81.4% vs 52.0%; P < .001). The differences in immune response, liver and kidney function and AIDS-related diseases were not significant between the 2 groups. For long-term effectiveness, viral suppression rates were similar (87.96% vs 84.59%; P = .135), with no significant differences in immune response, liver and kidney function, or AIDS-related diseases. Our study suggests that patients initiating ART with INSTI-containing regimens have worse physical status at baseline than patients starting with free ART drugs. Furthermore, we found better virological performances of INSTI-containing regimens in the short-term but not in the long-term due to a high rate of drug changes. Our findings have clinical implications and provide new evidence regarding the effectiveness of INSTI-containing regimens in LMICs.

HIV persistence: silence or resistance?

Despite decades of suppressive antiretroviral therapy, human immunodeficiency virus (HIV) reservoirs in infected individuals persist and fuel viral rebound once therapy is interrupted. The persistence of viral reservoirs is the main obstacle to achieving HIV eradication or a long-term remission. The last decade has seen a profound change in our understanding of the mechanisms behind HIV persistence, which appears to be much more complex than originally assumed. In addition to the persistence of transcriptionally silent proviruses in a stable latent reservoir that is invisible to the immune system, HIV is increasingly recognized to persist by resistance to the immune clearance, which appears to play a surprisingly prominent role in shaping the reservoir. In this review, we discuss some emerging insights into the mechanisms of HIV persistence, as well as their implications for the development of strategies towards an HIV cure.

The CARD8 inflammasome in HIV infection

The biggest challenge to immune control of HIV infection is the rapid within-host viral evolution, which allows selection of viral variants that escape from T cell and antibody recognition. Thus, it is impossible to clear HIV infection without targeting "immutable" components of the virus. Unlike the adaptive immune system that recognizes cognate epitopes, the CARD8 inflammasome senses the essential enzymatic activity of the HIV-1 protease, which is immutable for the virus. Hence, all subtypes of HIV clinical isolates can be recognized by CARD8. In HIV-infected cells, the viral protease is expressed as a subunit of the viral Gag-Pol polyprotein and remains functionally inactive prior to viral budding. A class of anti-HIV drugs, the non-nucleoside reverse transcriptase inhibitors (NNRTIs), can promote Gag-pol dimerization and subsequent premature intracellular activation of the viral protease. NNRTI treatment triggers CARD8 inflammasome activation, which leads to pyroptosis of HIV-infected CD4⁺ T cells and macrophages. Targeting the CARD8 inflammasome can be a potent and broadly effective strategy for HIV eradication.

Associations of modern initial antiretroviral drug regimens with all-cause mortality in adults with HIV in Europe and North America: a cohort study

BACKGROUND

Over the past decade, antiretroviral therapy (ART) regimens that include integrase strand inhibitors (INSTIs) have become the most commonly used for people with HIV starting ART. Although trials and observational studies have compared virological failure on INSTI-based with other regimens, few data are available on mortality in people with HIV treated with INSTIs in routine care. Therefore, we compared all-cause mortality between different INSTI-based and non-INSTI-based regimens in adults with HIV starting ART from 2013 to 2018.

METHODS

This cohort study used data on people with HIV in Europe and North America from the Antiretroviral Therapy Cohort Collaboration (ART-CC) and UK Collaborative HIV Cohort (UK CHIC). We studied the most common third antiretroviral drugs (additional to nucleoside reverse transcriptase inhibitor) used from 2013 to 2018: rilpivirine, darunavir, raltegravir, elvitegravir, dolutegravir, efavirenz, and others. Adjusted hazard ratios (aHRs; adjusted for clinical and demographic characteristics, comorbid conditions, and other drugs in the regimen) for mortality were estimated using Cox models stratified by ART start year and cohort, with multiple imputation of missing data.

FINDINGS

62 500 ART-naive people with HIV starting ART (12 422 [19·9%] women; median age 38 [IQR 30-48]) were included in the study. 1243 (2·0%) died during 188 952 person-years of follow-up (median 3·0 years [IQR 1·6-4·4]). There was little evidence that mortality rates differed between regimens with dolutegravir, elvitegravir, rilpivirine, darunavir, or efavirenz as the third drug. However, mortality was higher for raltegravir compared with dolutegravir (aHR 1·49, 95% CI 1·15-1·94), elvitegravir (1·86, 1·43-2·42), rilpivirine (1·99, 1·49-2·66), darunavir (1·62, 1·33-1·98), and efavirenz (2·12, 1·60-2·81) regimens. Results were similar for analyses making different assumptions about missing data and consistent across the time periods 2013-15 and 2016-18. Rates of virological suppression were higher for dolutegravir than other third drugs.

INTERPRETATION

This large study of patients starting ART since the introduction of INSTIs found little evidence that mortality rates differed between most first-line ART regimens; however, raltegravir-based regimens were associated with higher mortality. Although unmeasured confounding cannot be excluded as an explanation for our findings, virological benefits of first-line INSTIs-based ART might not translate to differences in mortality.

FUNDING

US National Institute on Alcohol Abuse and Alcoholism and UK Medical Research Council.

Predictors of Virological Failure Among People Living with HIV Switching from an Effective First-Line Antiretroviral Regimen

Aim of this study was to assess the predictors of virological failure (VF) among patients living with HIV (PLWHIV) switching from an effective first-line antiretroviral therapy (ART) regimen, and to evaluate the emergence of resistance-associated mutations. All adult patients enrolled in the Antiviral Response Cohort Analysis cohort who started ART after 2010, with at least 6 months of virological suppression (VS) before ART switch and with an available genotypic resistance test (GRT) at baseline were included. Thirty-two patients out of the 607 PLWHIV included (5.3%) experienced VF after a median of 11 months from ART switch. Younger age (adjusted Hazard Ratio [aHR] 0.96, 95% confidence interval [CI] 0.92-0.99, p = .023), being male who have sex with male (aHR 0.15, 95% CI 0.03-0.69, p = .014), and longer time from VS to ART switch (aHR 0.97, 95% CI 0.95-1.00, p = .021) resulted protective toward VF, while receiving a first-line regimen containing a backbone other than ABC/3TC or TXF/FTC (aHR 3.61, 95% CI 1.00-13.1, p = .050) and a boosted protease inhibitor as anchor drug (aHR 3.34, 95% CI 1.20-9.28, p = .021) were associated with higher risk of VF. GRT at the moment of VF was available only for 13 patients (40.6%). ART switch in patients with stable control of HIV infection is a safe practice, even if particular attention should be paid in certain cases of patients switching from regimens containing low-performance backbones or protease inhibitors.

Effectiveness of integrase strand transfer inhibitors in HIV-infected treatment-experienced individuals across Europe

OBJECTIVES

To explore the effectiveness and durability of integrase strand transfer inhibitor (INSTI)-based regimens in pre-treated subjects.

METHODS

Treatment-experienced individuals starting an INSTI-based regimen during 2012-2019 were selected from the INTEGRATE collaborative study. The time to virological failure [VF: one measurement of viral load (VL) ≥ 1000 copies/mL or two ≥ 50 copies/ml or one VL measurement ≥ 50 copies/mL followed by treatment change] and to INSTI discontinuation were evaluated.

RESULTS

Of 13 560 treatments analysed, 4284 were from INSTI-naïve, non-viraemic (IN-NV) individuals, 1465 were from INSTI-naïve, viraemic (IN-V) individuals, 6016 were from INSTI-experienced, non-viraemic (IE-NV) individuals and 1795 were from INSTI-experienced, viraemic (IE-V) individuals. Major INSTI drug resistance mutations (DRMs) were previously detected in 4/519 (0.8%) IN-NV, 3/394 (0.8%) IN-V, 7/1510 (0.5%) IE-NV and 25/935 (2.7%) IE-V individuals. The 1-year estimated probabilities of VF were 3.1% [95% confidence interval (CI): 2.5-3.8] in IN-NV, 18.4% (95% CI: 15.8-21.2) in IN-V, 4.2% (95% CI: 3.6-4.9) in IE-NV and 23.9% (95% CI: 20.9-26.9) in IE-V subjects. The 1-year estimated probabilities of INSTI discontinuation were 12.1% (95% CI: 11.1-13.0) in IN-NV, 19.6% (95% CI: 17.5-21.6) in IN-V, 10.8% (95% CI: 10.0-11.6) in IE-NV and 21.7% (95% CI: 19.7-23.5) in IE-V subjects.

CONCLUSIONS

Both VF and INSTI discontinuation occur at substantial rates in viraemic subjects. Detection of DRMs in a proportion of INSTI-experienced individuals makes INSTI resistance testing mandatory after failure.

No overall impact on rate of weight gain with integrase inhibitor-containing regimens in antiretroviral-naïve adults

OBJECTIVES

Integrase strand transfer inhibitors (INSTIs) are commonplace in modern antiretroviral therapy (ART). Increased weight gain with their use is increasingly scrutinized. We evaluated weight changes in treatment-naïve adults with HIV-1 attending a UK centre who started regimens including raltegravir or dolutegravir.

METHODS

A retrospective cohort study of adults prescribed an INSTI between January 2015 and March 2020 were categorized as having started an ART regimen containing raltegravir, dolutegravir, a protease inhibitor or a nonnucleoside reverse transcriptase inhibitor. Individuals with one or more weight measurement ≤ 5 years both pre- and post-ART initiation, who started a three-drug regimen with ≥ 6 months duration and achieved virological suppression (< 50 copies/mL) within 6 months were included. A random effects model with linear slope pre- and post-ART was used, adjusting for age, gender, ethnicity, ART regimen, backbone and year of initiation.

RESULTS

The cohort included 390 adults; 88.7% were male, 66.4% were of white ethnicity, their median age was 40 years, there was a median of six weight measurements, 2.2 years from diagnosis to ART initiation, 2.9 years from ART to the last weight measurement, and weight and body mass index at initiation were 75 kg and 24.1 kg/m² respectively. Of these, 254 (65%) started an INSTI. The average pre-ART rate of weight gain was 0.44 kg/year [95% confidence interval (CI): 0.19-0.70], increasing to 0.88 kg/year (0.63-1.10, p = 0.04) after ART initiation. Our adjusted model found no evidence of an association between ART regimen and rate of weight gain.

CONCLUSIONS

Weight increased in the cohort both pre- and post-ART. We found no evidence of a higher rate of weight gain following ART initiation with an INSTI compared with other regimens.

Does Syphilis Increase the Risk of HIV-RNA Elevation >200 Copies/mL in HIV-Positive Patients Under Effective Antiretroviral Treatment? Data From the ICONA Cohort

BACKGROUND

To assess the impact of syphilis infection on the risk of HIV-RNA elevation in people living with HIV (PLWH) with current HIV-RNA ≤50 copies/mL.

SETTING

The Italian Cohort Naive Antiretrovirals.

METHODS

All PLWH (2009-2020) under antiretroviral treatment with at least 2 consecutive HIV-RNA values ≤50 copies/mL before the date of syphilis diagnosis and at least 1 HIV-RNA determination after the syphilis event were enrolled. A control group of PLWH without syphilis was matched for mode of HIV transmission. Outcomes were defined using the first HIV-RNA measure in the time window ranging between -2 and +6 months of the diagnosis/index date. The primary outcome used a single value >200 copies/mL to define HIV-RNA elevation associated with risk of transmission. The association between syphilis infection and the protocol defined outcome was evaluated using logistic regression analysis.

RESULTS

Nine hundred twenty-six PLWH with a syphilis event were enrolled and matched with a random sample of 1370 PLWH without syphilis. Eighteen of the 926 (1.9%) with syphilis had ≥1 HIV-RNA >200 copies/mL in the window vs. 29/1370 (2.1%) of the not exposed (P = 0.77). In the multivariable analysis adjusted for age, year of diagnosis/index date, and clinical site, syphilis infection was not associated with the risk of HIV-RNA >200 copies/mL (adjusted odds ratio 0.81; 95% confidence interval 0.43-1.52, P = 0.508).

CONCLUSIONS

We did not find any evidence for an association between syphilis infection and viral elevation >200 copies/mL.

Non-nucleoside reverse transcriptase inhibitor-based combination antiretroviral therapy is associated with lower cell-associated HIV RNA and DNA levels as compared with therapy based on protease inhibitors

Background:

It remains unclear whether combination antiretroviral therapy (ART) regimens differ in their ability to fully suppress human immunodeficiency virus (HIV) replication. Here, we report the results of two cross-sectional studies that compared levels of cell-associated (CA) HIV markers between individuals receiving suppressive ART containing either a non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor (PI).

Methods:

CA HIV unspliced RNA and total HIV DNA were quantified in two cohorts (n = 100, n = 124) of individuals treated with triple ART regimens consisting of two nucleoside reverse transcriptase inhibitors (NRTIs) plus either an NNRTI or a PI. To compare CA HIV RNA and DNA levels between the regimens, we built multivariable models adjusting for age, gender, current and nadir CD4⁺ count, plasma viral load zenith, duration of virological suppression, NRTI backbone composition, low-level plasma HIV RNA detectability, and electronically measured adherence to ART.

Results:

In both cohorts, levels of CA HIV RNA and DNA strongly correlated (rho = 0.70 and rho = 0.54) and both markers were lower in NNRTI-treated than in PI-treated individuals. In the multivariable analysis, CA RNA in both cohorts remained significantly reduced in NNRTI-treated individuals (p_adj = 0.02 in both cohorts), with a similar but weaker association between the ART regimen and total HIV DNA (p_adj = 0.048 and p_adj = 0.10). No differences in CA HIV RNA or DNA levels were observed between individual NNRTIs or individual PIs, but CA HIV RNA was lower in individuals treated with either nevirapine or efavirenz, compared to PI-treated individuals.

Conclusions:

All current classes of antiretroviral drugs only prevent infection of new cells but do not inhibit HIV RNA transcription in long-lived reservoir cells. Therefore, these differences in CA HIV RNA and DNA levels by treatment regimen suggest that NNRTIs are more potent in suppressing HIV residual replication than PIs, which may result in a smaller viral reservoir size.

Funding:

This work was supported by ZonMw (09120011910035) and FP7 Health (305522).