Efficacy and Safety of a Simplified Lamivudine Plus Dolutegravir Dual Therapy in HIV-1-Infected Patients: A Multicenter Cohort Study in China

BACKGROUND

Results from both clinical trials and real-world observational studies suggest that lamivudine plus dolutegravir (3TC + DTG) dual therapy has excellent virological efficacy and safety in HIV-1-infected patients. However, there is still no relevant study related to this dual therapy reported in China.

METHODS

In this multicenter, retrospective, observational study that included HIV-1-infected patients in China, baseline and follow-up data were collected to analyze the virological suppression rate, immune restoration, and adverse events during follow-up in HIV-1-infected patients who switched to the 3TC + DTG dual therapy.

RESULTS

This study recruited 112 HIV-1-infected patients, including 101 men (90.2%), with a median age of 44.0 years (IQR: 33.00-57.75) and median CD4+ T-cell count of 432.13 cells/μL (IQR: 237.75-578.50). The overall virological suppression rate was 94.5% at the 24-week follow-up. However, the virological suppression rates of men who have sex with men patients and patients with CD4+ T-cell count of <350 cells/μL were higher than the baseline value (P < 0.05) at week 24. The results of Cox regression analysis showed that the baseline CD4+ T-cell count was an independent determinant of immune restoration in patients, and patients with baseline CD4+ T-cell count of 350-500 cells/μL outperformed patients with baseline CD4+ T-cell count of <350 cells/μL in immune restoration (hazard ratio: 4.469, 95% confidence interval: 1.801 to 11.091, P = 0.001). Adverse events were reported in 5 patients (incidence rate of 4.5%); among them, 3 patients developed neuropsychiatric symptoms. Results from the laboratory data analysis showed that patients with grade 1 and 2 adverse events had elevated levels of low-density lipoprotein cholesterol and total bilirubin. Furthermore, grade 3 and 4 adverse events were associated with the elevation of blood glucose level in 4 patients.

CONCLUSIONS

Thus, the 3TC + DTG dual therapy displayed an excellent virological efficacy against HIV-1 infections and had an acceptable safety profile, with predominantly mild adverse events in HIV-1-infected patients in China.

Long term dual antiretroviral therapy: A real life retrospective countrywide Israeli study

AIM

Combined antiretroviral treatment (cART) traditionally consists of three antiretroviral medications, while two-drug regimens (2DR), historically used infrequently, recently been suggested to be non-inferior to three-drug regimens, is emerging as a potential treatment option and is currently a recommended option for treatment initiation in many guidelines.

PURPOSE

Characterize the indications and clinical efficacy of 2DR use at a real-life setting in a nation-wide survey.

METHODS

A cross-sectional survey of Israeli patients treated by 2DR until July 2019, included demographic, immunologic, virologic, genotypic and biochemical/metabolic parameters at diagnosis, ART initiation, 2DR initiation and following 24, 48, 96 and 144 weeks of 2DR treatment.

RESULTS

176 patients were included in the study. In contrast to historical data implicating ART resistance and adverse effects as the major reasons leading to 2DR switching, treatment simplification was the main reason leading to 2DR treatment in 2019. 2DR that included INSTI and PI were more commonly used in cases of drug resistance, while a combination of INSTI and NNRTI was used in all other 2DR indications. A switch to 2DR induced a mean CD4 T cell increase from 599 cells/μl at treatment initiation to 680 cells/μl at 96 weeks of treatment p<0.001 and viral suppression improvement from 73.9% at initiation to 87.0% at 48 weeks of treatment (p = 0.004). PI and INSTI 2DR was inferior in suppressing viral levels compared to other 2DRs but used for subset of more complex patients.

CONCLUSIONS

2DR in a large-scale real-life nation-wide survey proved to be safe and effective. Most 2DRs, other than PI and INSTI, were similarly effective in suppressing HIV viremia and in elevating CD4 T cell counts.

Efficacy and durability of two- vs. three-drug integrase inhibitor-based regimens in virologically suppressed HIV-infected patients: Data from real-life ODOACRE cohort

OBJECTIVES

The aim of the present study was to compare the efficacy and durability of treatment switch to two-drug (2DR) vs. three-drug (3DR) integrase inhibitor (InSTI)-based regimens in a real-life setting.

METHODS

Within the ODOACRE cohort, we selected adult patients with HIV RNA < 50 copies/mL switching to an InSTI-based 2DR or 3DR. Survival analyses were performed to estimate the probability of virological failure (VF, defined as one HIV RNA > 1000 copies/mL or two consecutive HIV RNA > 50 copies/mL) and treatment discontinuation (TD, defined as any modification, intensification or interruption of the regimen), and to evaluate their predictors.

RESULTS

Overall, 1666 patients were included, of whom 1334 (80%) were treated with a 3DR (19.9%, 25.0% and 55.1% elvitegravir-, raltegravir- and dolutegravir-based, respectively) and 332 (20%) with a 2DR (79.2% dolutegravir + lamivudine and 20.8% dolutegravir + rilpivirine). Over a median (interquartile range) follow-up of 100 (52-150) weeks, 52 (3.1%) patients experienced VF with an incidence of 1.5/100 person-year of follow-up (PYFU). The estimated 96-week probability of VF was similar for the 2DR and 3DR groups (2.3% vs. 2.8%, P = 0.53), but it was higher for elvitegravir (4.9%) and raltegravir (5.0%) than for dolutegravir (1.5%) (P = 0.04). Four hundred (24%) patients discontinued their InSTI-based regimen, with an incidence of 11.3/100 PYFU. At 96 weeks, 3DRs showed a higher probability of TD for any reason (20.6% vs. 11.2%, P < 0.001) and TD for toxicity (9.0% vs. 6.6%, P = 0.02) when compared with 2DRs. A higher risk of TD for central nervous system toxicity was observed for dolutegravir than for elvitegravir and raltegravir (4.0% vs. 2.5% vs. 0.6%, P = 0.005).

CONCLUSIONS

In virologically suppressed HIV-infected patients, 2DRs showed an efficacy similar to 3DRs but with better tolerability.

Dolutegravir response in antiretroviral therapy naïve and experienced patients with M184V/I: Impact in low-and middle-income settings

BACKGROUND

Dolutegravir (DTG) is now recommended to all HIV infected adults, adolescents, and children of right age by WHO. The low cost of $75 per year for generic DTG-based combination, has allowed 3.9 million people living with HIV (PLWH) in low and middle-income countries (LMICs) access to DTG. Lamivudine and emtricitabine associated M184V/I mutation is highly prevalent in PLWH and the majority of HIV infected individuals receiving DTG regimens may already be carrying M184V/I mutation.

DISCUSSION

Despite high prevalence of M184V/I in antiretroviral therapy (ART) experienced patients, DTG treatment outcomes will likely not be adversely affected by this mutation. The use of DTG in ART naïve has been largely characterised by rare emergence of resistance and virological failure. DTG-based regimens have to great extent been effective at maintaining viral suppression in treatment experienced PLWH carrying M184V/I.

CONCLUSIONS

Initiating patients on DTG may help preserve more treatment options for HIV infected individuals living in LMICs. High genetic barrier to the development of resistance associated with DTG and progressive viral suppression in patients switched to DTG-based therapy with M184V/I, may encourage better DTG outcomes and help in curbing increasing levels of HIV drug resistance in LMICs.

Risks and benefits of reducing the number of drugs to treat HIV-1 infection

Introduction: Despite the efficacy and safety of antiretroviral therapy, new treatment options are needed to address the concerns of patients and physicians regarding long-term toxicities, costs, and convenience of lifelong antiretroviral therapy. To achieve this goal, one strategy is to reduce the number of drugs in the antiretroviral regimen.Areas covered: We review the recent evidence on the efficacy and safety of reduced drug regimens and their potential risks and benefits. There is currently strong evidence showing that some two-drug regimens have a comparable efficacy and short-term safety compared to standard three-drug regimens. The fixed-dose combination of dolutegravir/lamivudine is already an alternative for many treatment-naïve and virologically suppressed HIV-1 infected adults supported by large randomized clinical trials. The co-formulation dolutegravir plus rilpivirine is also a switch strategy for maintenance therapy. Long-acting injectable cabotegravir plus rilpivirine has already regulatory approval, and islatravir plus doravirine is an expected option in the near future. Some two-drug regimens have not been as successful.Expert opinion: Long-term safety issues of these two-drug regimens remain to be determined, but with the overwhelming evidence available in virological control and short-term safety, the potential benefits of some of these two-drug regimens appear to outweigh the risks.

Dolutegravir plus lamivudine for the treatment of HIV-1 infection

Introduction: Recent data on the 2-drug regimen (2DR) with dolutegravir (DTG) plus lamivudine (3TC) have shown high efficacy and tolerability both in treatment-naïve and experienced HIV-positive patients. Current guidelines recommend DTG+3TC as an alternative to triple antiretroviral therapy (ART) in selected patients to reduce long-term toxicity and costs.Areas covered: This review is intended to provide insight about the efficacy, safety, and tolerability of a 2DR with DTG+3TC in naïve and treatment-experienced patients.Expert opinion: Data from clinical trials and from real-life show that DTG+3TC is an effective and safe switch option for the treatment of experienced patients. In treatment-naïve patients, DTG+3TC has shown non-inferiority compared to standard 3-drug regimens but is less effective in severely immunocompromised naïve patients (i.e. with a CD4+ cell count below 200 cell/mm3); furthermore, current guidelines have upgraded this dual regimen to recommended first-line strategy, but indicate that it should not be used without genotypic resistance results. Moreover, this regimen is not feasible for HBV-coinfected individuals and should not be used during pregnancy. Currently, out of 2-drug regimens, DTG+3TC is one of clinicians' preferred option as it requires no pharmacokinetic booster, has a low risk of drug interaction, and does not require food intake.

Retrospective study on the outcome of two-drug regimens based on dolutegravir plus one reverse transcriptase inhibitor in virologically-suppressed HIV-infected patients

This was a retrospective study on the efficacy and drug resistance mutations selected at virological failure (VF) in prospectively-followed HIV-infected patients switched to dolutegravir plus rilpivirine (DTG+RPV) or lamivudine (DTG+3TC) while virologically suppressed (HIV-RNA <50 copies/mL). VF was defined as HIV-RNA >50 copies/mL in two consecutive determinations or in a single determination if followed by treatment modification, or >1000 copies/mL in a single determination. Totally, 374 patients were analysed (307 switched to DTG+3TC and 67 to DTG+RPV); 220 had documented historical resistance. The median (IQR) time with HIV-RNA <50 copies/mL before switch was 4.52 (1.93-8.14) years. VF occurred in 17 patients after a median of 1.74 (0.90-2.46) years of follow-up in the 3TC group [incidence rate (95% CI) 3.34 (2.08-5.37) per 100-PYFU] and in 2 patients after a median of 1.78 (1.10-2.99) years of follow-up in the RPV group [incidence rate (95% CI) 1.57 (0.4-6.28) per 100-PYFU]. The 48-week estimated probabilities to maintain virological suppression during treatment with a two-drug regimen were 97.8% (95% CI 95.1-99.0%) vs. 98.3% (95% CI 88.6-99.8%) in the 3TC versus RPV group (P = 0.311). At switch, patients with VF had undetectable HIV-RNA since 0.71 (0.23-1.07) years versus 1.49 (0.64-2.2) years in those without VF (P = 0.001). In the 3TC group, VF was not associated with the presence of historical resistance to nucleoside analogues, and DTG-resistant variants were not selected at VF. One VF to DTG+RPV occurred because of historical resistance to RPV, accompanied by newly selected G140A and Q148R mutations. VF was infrequent with these regimens and was negatively associated with duration of viral undetectability. Drug resistance mutations selected at failure of these regimens were those expected in case of failure of any regimen including DTG, 3TC or RPV, but the impact of resistance to NRTIs on efficacy of DTG+3TC seems lower than expected.

Uptake and effectiveness of two-drug compared with three-drug antiretroviral regimens among HIV-positive individuals in Europe

OBJECTIVE

To assess the use of two-drug antiretroviral regimens (2DR) and virologic and immunologic outcomes compared with three-drug regimens (3DR) in the EuroSIDA cohort.

DESIGN

Multicentre, prospective cohort study.

METHODS

Logistic regression was used to analyse the uptake and outcomes among HIV-positive individuals who started or switched to a 2DR compared with those on a 3DR. Virologic outcomes were assessed on-treatment as the proportion of individuals with controlled viral load (<400 copies/ml), or with a composite modified FDA snapshot endpoint (mFDA), with mFDA success defined as controlled viral load at 6 months or 12 months for individuals with a known viral load, no regimen changes, AIDS or death. Immunologic response was defined as a 100 cells/μl or a 25% increase in CD4 cell counts from baseline.

RESULTS

Between 1 July 2010 and 31 December 2016, 423 individuals started or switched to a 2DR (eight antiretroviral-naive) and 4347 started a 3DR (566 naive). Individuals on 2DR tended to have suppressed viral load, higher CD4 cell counts and more comorbidities at baseline compared with those on 3DR. There were no differences in the proportions of individuals who obtained on-treatment or mFDA success, and no significant differences in the adjusted odds ratios for mFDA success or immunologic responses between the 2DR and 3DR groups at 6 months or 12 months.

CONCLUSION

In routine clinical practice, 2DR were largely used for virologically suppressed individuals with higher cumulative exposure to antiretrovirals and comorbidities. Virologic and immunologic outcomes were similar among those on 2DR or 3DR, although confounding by indication cannot be fully excluded due to the observational nature of the study.

Switch to dolutegravir and unboosted atazanavir in HIV-1 infected patients with undetectable viral load and long exposure to antiretroviral therapy

: We evaluated the efficacy and safety of a two-drug regimen including dolutegravir (DTG) and unboosted atazanavir (uATV) in 151 HIV-1 infected patients with HIV-RNA of more than 50 copies/ml. During a median follow-up of 62 (42-97) weeks, two virological failures (1%) and 13 treatment discontinuations (9%) occurred; the 48-week probability of virological failure was 0.8% (95% confidence interval 0.2-5.6%). Switch to DTG + uATV may represent a boosting and transcriptase reverse inhibitors sparing otion in individuals with long exposure to antiretroviral therapy and risk of cardiovascular disease.

Integrase Inhibitors: After 10 Years of Experience, Is the Best Yet to Come?

The era of the integrase strand transfer inhibitors (INSTIs) for the treatment of human immunodeficiency virus (HIV) infection began with raltegravir in 2007. Since that time, several other INSTIs have been introduced including elvitegravir, dolutegravir, and, most recently, bictegravir, that have shown great utility as part of antiretroviral regimens in both treatment-naive and treatment-experienced patients. At present, antiretroviral guidelines fully endorse the INSTI class as part of all first-line treatment regimens. After 10 years of experience with INSTIs, newer agents are on the horizon such as cabotegravir and MK-2048 for potential use as either HIV pre-exposure prophylaxis or maintenance therapy. This review provides a brief overview of the INSTI class including agents currently available and those still in development, reviews available data from both completed and ongoing clinical trials, and outlines simplification strategies using INSTIs.

Efficacy and safety of switching to dolutegravir plus emtricitabine/tenofovir disoproxil fumarate (TDF) or elvitegravir/cobicistat/emtricitabine/TDF in virologically suppressed HIV-infected patients in clinical practice: results from a multicentre, observational study

OBJECTIVES

The aim of the study was to compare the efficacy and tolerability of switching antiretroviral therapy to dolutegravir + emtricitabine/tenofovir disoproxil fumarate (TDF) with those of switching to elvitegravir/cobicistat/emtricitabine/TDF in clinical practice.

METHODS

In a multicentre real-life observational study, we analysed data for HIV-infected patients on antiretroviral treatment with viral load < 50 HIV-1 RNA copies/mL switching to dolutegravir + emtricitabine/TDF (dolutegravir group) or elvitegravir/cobicistat/emtricitabine/TDF (elvitegravir group). Follow-up was censored at 48 weeks.

RESULTS

The 48-week estimated proportion maintaining virological efficacy was 96.1% with dolutegravir (n = 123) and 95.4% with elvitegravir (n = 186; P = 0.941). Patients in the dolutegravir group showed more treatment discontinuations, but these were mainly as a result of simplification. The elvitegravir group showed more discontinuations because of renal adverse events (2.7% versus 0% with dolutegravir). Interestingly, no difference was observed between the two regimens in central nervous system toxicity-related discontinuations. Switching to dolutegravir was associated with a better blood lipid profile.

CONCLUSIONS

Switching to dolutegravir + emtricitabine/TDF was associated with similar efficacy and tolerability to switching to elvitegravir/cobicistat/emtricitabine/TDF in virologically suppressed patients in clinical practice, although reasons for discontinuation showed differences between regimens. These results should be interpreted with caution, as this is a nonrandomized comparison.

Virologic failure and HIV drug resistance on simplified, dolutegravir-based maintenance therapy: Systematic review and meta-analysis

Background: Dolutegravir-containing maintenance therapy is a promising simplification strategy for virologically suppressed HIV-infected individuals. However, most of the available data to inform this strategy come from small, uncontrolled studies. We estimated the proportion of HIV-infected patients experiencing virological failure (VF) and developing drug resistance on dolutegravir (DTG)-based maintenance therapy. Methods: We searched Medline, Embase, Cochrane Central, Web of Science, and conference abstracts for studies assessing VF on DTG-based maintenance therapy. Studies including ≥5 adults with an undetectable viral load on antiretroviral therapy (ART) who switched to a DTG-based mono- or dual therapy were included. Pooled proportions of VF were estimated using random-intercept logistic meta-regression and acquired drug resistance mutations described for each strategy. Results: Of 1719 studies considered, 21 met our selection criteria, including seven interventional and 14 observational studies. Eight studies including 251 patients assessed VF on DTG monotherapy and fourteen studies including 1670 participants VF on dual therapy. The participant's median age ranged from 43 to 63 years, their median nadir CD4 count from 90 to 399 cells/µl, and 27.6% were female. The proportion of participants experiencing VF on DTG-monotherapy was 3.6% (95% confidence interval [CI] 1.9-6.7) at 24 weeks and 8.9% (95% CI 4.7-16.2) at 48 weeks. Resistance mutations developed in seven (3.6%) participants on DTG-monotherapy. Among patients on dual therapy, ten (0.7%, 95% CI 0.4-1.3) experienced VF by 48 weeks and none developed resistance to DTG. In adjusted analyses, VF at 24 weeks was less likely on dual therapy than on monotherapy (adjusted odds ratio: 0.10, 95% CI 0.03-0.30). Conclusions: Whereas VF is relatively common on DTG maintenance monotherapy, DTG-based dual therapy appears to be a promising simplification strategy for individuals with a suppressed HIV viral load on triple-ART.

Virologic failure and HIV drug resistance on simplified, dolutegravir-based maintenance therapy: Systematic review and meta-analysis

Background: Dolutegravir-containing maintenance therapy is a promising simplification strategy for virologically suppressed HIV-infected individuals. However, most of the available data to inform this strategy come from small, uncontrolled studies. We estimated the proportion of HIV-infected patients experiencing virological failure (VF) and developing drug resistance on dolutegravir (DTG)-based maintenance therapy. Methods: We searched Medline, Embase, Cochrane Central, Web of Science, and conference abstracts for studies assessing VF on DTG-based maintenance therapy. Studies including ≥5 adults with an undetectable viral load on antiretroviral therapy (ART) who switched to a DTG-based mono- or dual therapy were included. Pooled proportions of VF were estimated using random-intercept logistic meta-regression and acquired drug resistance mutations described for each strategy. Results: Of 1719 studies considered, 21 met our selection criteria, including seven interventional and 14 observational studies. Eight studies including 251 patients assessed VF on DTG monotherapy and fourteen studies including 1670 participants VF on dual therapy. The participant's median age ranged from 43 to 63 years, their median nadir CD4 count from 90 to 399 cells/µl, and 27.6% were female. The proportion of participants experiencing VF on DTG-monotherapy was 3.6% (95% confidence interval [CI] 1.9-6.7) at 24 weeks and 8.9% (95% CI 4.7-16.2) at 48 weeks. Resistance mutations developed in seven (3.6%) participants on DTG-monotherapy. Among patients on dual therapy, ten (0.7%, 95% CI 0.4-1.3) experienced VF by 48 weeks and none developed resistance to DTG. In adjusted analyses, VF at 24 weeks was less likely on dual therapy than on monotherapy (adjusted odds ratio: 0.10, 95% CI 0.03-0.30). Conclusions: Whereas VF is relatively common on DTG maintenance monotherapy, DTG-based dual therapy appears to be a promising simplification strategy for individuals with a suppressed HIV viral load on triple-ART.

Impact of the M184V Resistance Mutation on Virological Efficacy and Durability of Lamivudine-Based Dual Antiretroviral Regimens as Maintenance Therapy in Individuals With Suppressed HIV-1 RNA: A Cohort Study

Background

Dual therapy (DT) with boosted protease inhibitors (bPIs) plus lamivudine has been shown to be superior to bPI monotherapy in virologically suppressed patients despite previous selection of the lamivudine resistance M184V mutation. We compared the virological efficacy of lamivudine-based DT in patients with and without a history of M184V detection.

Methods

We retrospectively analyzed patients with HIV-RNA ≤50 copies/mL switching to DT with at least 1 previous resistance genotype in the ARCA database. Time to virological failure (VF; HIV-RNA ≥200 copies/mL or 2 consecutive HIV-RNA >50 copies/mL) and to treatment discontinuation (TD) was analyzed by survival analysis.

Results

Four hundred thirty-six patients switching to lamivudine plus bPIs (70%) or integrase inhibitors (30%) were included. Patients with M184V (n = 87) were older, had lower nadir CD4+ cell count, longer duration of antiretroviral therapy and of virologic suppression, and higher rate of hepatitis C virus infection compared with patients without M184V. The 3-year probability of remaining free from VF was 91.9% (95% confidence interval [CI], 86.6–97.2) without M184V and 87.8% (95% CI, 78.4–97.2) with M184V (P = .323). The time to TD did not differ between groups. Multivariate analysis adjusting for baseline variables differing between groups also did not detect M184V as being associated with VF or TD; however, the 3-year probability of remaining free of viral blips (isolated HIV-RNA 51–199 copies/mL) was 79.8% (95% CI, 67.8%–91.8%) with M184V vs 90.1% (95% CI, 84.0%–96.2%) without M184V (P = .016).

Conclusions

Previous selection of M184V did not increase the risk of VF or TD with lamivudine-based DT but was associated with a higher probability of viral blips.

Dolutegravir Dual Therapy as Maintenance Treatment in HIV-Infected Patients: A Review

OBJECTIVE

To review available evidence for dolutegravir-based dual therapy as maintenance treatment in HIV-1 infected patients.

DATA SOURCES

A literature search was conducted using PubMed, MEDLINE, and Google Scholar to the end of January 2018. Conference abstracts and article bibliographies were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

All English-language, randomized, and observational studies were included.

DATA SYNTHESIS

In all, 12 studies were identified: 10 were observational, and 2 were randomized trials. Rilpivirine or lamivudine were the most common second agent used in combination with dolutegravir. Virological suppression seen in observational studies appear promising; however, the most compelling evidence to date is the 48-week results from 2 large open-label randomized trials (SWORD 1 and 2). These studies found that dual therapy with rilpivirine and dolutegravir was noninferior to 3- or 4-drug combination antiretroviral therapy (cART). The long-term efficacy, safety, and tolerability of dual therapy, as compared with usual cART, are less clear and require further data.

CONCLUSIONS

Regimen switching in virally suppressed HIV-1-infected patients may be considered to reduce pill burden or dosing frequency, decrease short- or long-term toxicity, prevent or manage drug-drug interactions, and/or decrease cost. Based on available evidence, a switch to dual therapy with dolutegravir and rilpivirine appears viable for virologically suppressed patients without prior resistance mutations to these agents. Randomized studies of other dual-therapy regimens that include dolutegravir and longer-term follow-up as well as cost-effectiveness analyses are needed to provide confirmation that this strategy offers advantages to traditional cART regimens.

Effectiveness, Safety, and Tolerability of a Switch to Dual Therapy with Dolutegravir Plus Cobicistat-Boosted Darunavir in Treatment-Experienced Patients with Human Immunodeficiency Virus

BACKGROUND

Dual regimen with dolutegravir plus cobicistat-boosted darunavir (DTG/DRV/c) is reasonable alternative option for patients with existing resistance and/or intolerance to nucleoside reverse transcriptase inhibitors (NRTIs).

MATERIAL AND METHODS

All patients who switched to DTG/DRV/c among treatment-experienced patients with human immunodeficiency virus (HIV) in a tertiary university hospital were selected. We analyzed the effectiveness, safety, and tolerability based on serial laboratory data and clinical findings. The primary endpoint was defined as the proportion of patients with plasma HIV RNA below 50 copies/mL at week 48 after switch. Secondary endpoints included evaluation of safety and tolerability.

RESULTS

Thirty-one patients were retrospectively analyzed. The main reasons for the change to DTG/DRV/c were treatment failure in 13 patients (41.9%), simplification in 12 patients (38.7%), and adverse drug reaction in 6 patients (19.4%). Among the 13 patients who switched owing to treatment failure, the proportion of patients in whom the viral loads were suppressed to less than 50 copies/mL increased from 0% at baseline to 45% at 4 weeks, 50% at 12 weeks, 50% at 24 weeks, and 66.7% at 48 weeks. HIV virus levels decreased and CD4⁺ T cell counts increased during the follow-up period. In non-treatment failure patients (18 patients), the levels of viral suppression and CD4⁺ T cells were maintained. There were no significant differences in renal function, liver function, glucose levels, and lipid profile before and after regimen changes. The tolerability was very good: 30 patients (96.8%) tolerated the drugs well and only 1 patient discontinued owing to no improvement in renal insufficiency. Two patients (6.4%) in treatment failure group failed to reach viral suppression.

CONCLUSION

The use of DTG/DRV/c in HIV treatment-experienced patients appears to be a very good regimen for switch therapy that is effective and well tolerated, without significant adverse drug reaction.

Strength in Amalgamation: Newer Combination Agents for HIV and Implications for Practice

Antiretroviral (ART) therapy for the treatment of human immunodeficiency virus (HIV) infection has undergone significant changes over the past 30 years. Many single-tablet regimens (STRs), including newer fixed-dose combination (FDC) tablets, are available, offering patients several options for choosing a treatment regimen that works best for them. Given these changes, patients are more likely to adhere to treatment, achieve better clinical outcomes, and experience both fewer side effects and drug-drug interactions. Newer STRs include dolutegravir (DTG)/lamivudine (3TC)/abacavir (ABC) (Triumeq; Viiv Healthcare, Research Triangle Park, NC), rilpivirine (RPV)/emtricitabine (FTC)/tenofovir alafenamide (TAF) (Odefsey; Gilead, Foster City, CA), RPV/FTC/tenofovir disoproxil fumarate (TDF) (Complera; Gilead), elvitegravir (EVG)/cobicistat (COBI)/FTC/TDF (Stribild; Gilead), and EVG/COBI/FTC/TAF (Genvoya; Gilead). Recently approved FDCs, such as atazanavir (ATV)/COBI (Evotaz; Bristol-Myers Squibb, Princeton, NJ), darunavir (DRV)/COBI (Prezcobix; Janssen Products, Titusville NJ), and FTC/TAF (Descovy; Gilead), are also now available. The Department of Health and Human Services treatment guidelines for HIV recommend many of these integrase strand transfer inhibitor (INSTI) STRs as a preferred choice for initiation of treatment in both ART-naive and -experienced patients because they offer comparably faster rates of virologic suppression, reduced rates of resistance development (especially with DTG), and overall better adherence than protease inhibitors or NNRTIs. Numerous phase 3 clinical trials support these recommendations including several switch or simplification clinical trials. Notably, the novel pharmacokinetic booster COBI, with its water soluble properties, has enabled the development and coformulation of a few of these STRs and FDCs. Also, a newer tenofovir salt formulation, TAF, has an advantageous pharmacokinetic profile, contributing to better overall renal and bone tolerability compared with TDF. Further simplification regimens comprising dual ART therapies are currently being explored. This review provides an overview of the clinical efficacy and safety data for these coformulated agents, highlighting the relative impact on comparative adverse events, assessing the potential for experiencing fewer drug-drug interactions, and discussing the clinical implications regarding adherence to treatment.

Lamivudine/dolutegravir dual therapy in HIV-infected, virologically suppressed patients

BACKGROUND

Little is known about the applicability of dual treatments based on integrase inhibitors. We explored the combination of lamivudine + dolutegravir as an option when switching from standard cART in virologically suppressed patients.

METHODS

In this prospective cohort we enrolled patients previously switched to 3TC + DTG who were 18 years or older, with no previous resistance mutations to the used drugs, having a HIV-RNA <50 copies/ml for 6 months or longer, negative for HBsAg and on a stable (>6 months) cART.

RESULTS

Ninety-four individuals were included. They were mostly men (77.7%) with a mean age of 53 years. They presented 159 co-morbidities including cardiovascular, bone, hepatic, kidney, and CNS diseases. Because of these pathologies, they took 207 non-ARV drugs (mean 2.2 per patient). Median duration of viral suppression was 77.5 months (IQR 61). All subjects were prospectively followed up to week 24 and all remained on dual therapy during the whole period. Neither virological failure, nor viral blip was detected. The median CD4 count rose from 658 cells/mcl (IQR 403) to 724 cells/mcl (IQR 401) (P = 0.006) without a significant (P = 0.44) change in the CD4/CD8 ratio. A significant (P < 0.0001) increment of median creatinine from 0.87 mg/dl (IQR 0.34) to 0.95 mg/dl (IQR 0.29) was observed in the first 2 months but thereafter leveled on these values (1.00 mg/dl; IQR 0.35) (P = 0.111 compared to 2 months). The lipid profile slightly improved. The daily cost of cART was significantly (P < 0.0001) reduced of 6.89 euros (SD 6.10).

DISCUSSION

Switching to a dual cART regimen based on lamivudine + dolutegravir maintains virological efficacy up to week 24, and is associated to slight improvements of the immunologic and metabolic status. The strategy allows to freely using concomitant medications for associated pathologies. The dual therapy is less expensive in economic terms.

CONCLUSION

Although still limited evidence exists, a dolutegravir-based dual therapy in combination with lamivudine shows promising results to be confirmed in larger controlled trials.

Abacavir + dolutegravir + lamivudine for the treatment of HIV

INTRODUCTION

Since the last revision of both European and American guidelines (EACS and DHHS), new data from clinical trials and cohort studies, as well as experience in clinical practice, have prompted significant changes to the list of recommended/preferred options for the treatment of HIV infected patients, highlighted the role of INSTI-based regimens. Dolutegravir (DTG) in combination with abacavir/lamivudine (ABC/3TC) is one of these preferred regimens in multiple clinical scenarios, including treatment-naive and treatment-experienced patients.

AREAS COVERED

In this article we describe the coformulation of ABC/3TC/DTG in a fixed-dose combination (FDC) approved in September 2014 for the treatment of HIV infection. We focused our research on the efficacy and safety data resulting from phase 2 and 3 clinical study, particularly on the results of both SPRING (1 and 2) and SINGLE studies.

EXPERT OPINION

Triple combination therapy with ABC/3TC/DTG should be considered among the initial options for treatment-naive patients, being effective, well tolerated, with a high genetic barrier to resistance along with a convenient once-daily administration. In treatment-experienced patients the single-tablet regimen (STR) based on ABC/3TC/DTG could be used as simplification strategy in subjects with sustained viral suppression, as the high genetic barrier of DTG should ensure a safe switch from both NNRTI or PI based regimens.