Lopinavir-ritonavir monotherapy versus lopinavir-ritonavir and two nucleosides for maintenance therapy of HIV

Potential Drugs for the Treatment of COVID-19: Synthesis, Brief History and Application

Coronaviruses (CoVs) belonging to the Betacoronavirus group, an unusually large RNA genome, are characterized by club-like spikes that project from their surface. An outbreak of a novel coronavirus 2019 (nCOVID-19) showing a unique replication strategy and infection has posed a significant threat to international health and the economy around the globe. Scientists around the world are investigating few previously used clinical drugs for the treatment of COVID-19. This review provides synthesis and mode of action of recently investigated drugs like Chloroquine, Hydroxychloroquine, Ivermectin, Selamectin, Remdesivir, Baricitinib, Darunavir, Favipiravir, Lopinavir/ritonavir and Mefloquine hydrochloride that constitute an option for COVID-19 treatment.

Convalescent Blood: Current Perspective on the Efficacy of a Legacy Approach in COVID-19 Treatment

Since early 2020, COVID-19 has wreaked havoc in many societies around the world. As of the present, the SARS-CoV-2-borne disease is propagating in almost all countries, affecting hundreds of thousands of people in an unprecedented way. As the name suggests, the novel coronavirus, widely known as SARS-CoV-2, is a new emerging human pathogen. A novel disease of relatively unknown origin, COVID-19 does not seem to be amenable to the currently available medicines since there is no specific cure for the disease. In the absence of any vaccine or effective antiviral medication, we have no tools at our disposal, but the method of quarantine, be it domestic or institutional, to hinder any further progression of this outbreak. However, there is a record of physicians in the past who practiced convalescent blood transfusion. To their awe, the method seemed to be useful. It is anticipated that these contemporary methods will outdo any other vaccination process in the time being, as blood transfusion is instead a cost-effective and time-friendly technique. Following a successful trial, this new approach of contemporary nature to a viral disease may serve as an emergency intervention to intercept infectious outbreaks and prevent an impending epidemic/pandemic. In this review, we document the most recent evidence regarding the efficiency of convalescent plasma and serum therapy on SARS, MERS, and particularly COVID-19, while discussing potential advantages and possible risks of such practice.

Recent Developments on Therapeutic and Diagnostic Approaches for COVID-19

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made a serious public health threat worldwide with millions of people at risk in a growing number of countries. Though there are no clinically approved antiviral drugs and vaccines for COVID-19, attempts are ongoing for clinical trials of several known antiviral drugs, their combination, as well as development of vaccines in patients with confirmed COVID-19. This review focuses on the latest approaches to diagnostics and therapy of COVID-19. We have summarized recent progress on the conventional therapeutics such as antiviral drugs, vaccines, anti-SARS-CoV-2 antibody treatments, and convalescent plasma therapy which are currently under extensive research and clinical trials for the treatment of COVID-19. The developments of nanoparticle-based therapeutic and diagnostic approaches have been also discussed for COVID-19. We have assessed recent literature data on this topic and made a summary of current development and future perspectives.

Recent advances in therapeutic modalities and vaccines to counter COVID-19/SARS-CoV-2

The novel coronavirus disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has rapidly spread across the world. This resulted an alarming number of fatalities with millions of confirmed infected cases, pretending severe public health, economic, and social threats. There is no specific therapeutic drugs or licensed vaccines or treatments to fight against lethal COVID-19 infections. Given the significant threats of COVID-19, the global organizations are racing to identify epidemiological and pathogenic mechanisms of COVID-19 to find treatment regimens and effective therapeutic modalities for future prevention. Herein, we reviewed the therapeutic interventions and vaccines for COVID-19 based on the existing knowledge and understanding of similar coronaviruses, including MERS-CoV and SARS-CoV. The information constitutes a paramount intellectual basis to sustenance ongoing research for the discovery of vaccines and therapeutic agents. This review signifies the most available frontiers in the viral vaccine development approaches to counter the COVID-19/SARS-CoV-2.

The COVID-19 pandemic: biological evolution, treatment options and consequences

The spread of novel coronavirus SARS-CoV-2, the cause of the pandemic COVID-19 has emerged as a global matter of concern in the last couple of months. It has rapidly spread around the globe, which initially began in the city of Wuhan, People’s Republic of China and is hypothesized to originate from the group of Rhinolophus bats. Till date, there has been no clinically proven vaccine against the SARS-CoV-2 and thus the doctors are employing the other well-known techniques, which have previously successfully tackled similar other human coronaviruses. To prevent the further spread of COVID-19, doctors are advising isolation of the infected patients, and also regular washing of hands and the use of face mask for the common people. In the wake of the COVID-19 outbreak, the countries are going for nationwide lockdown as the only preventive measure to avert community transmission of this disease, which is having economic, social and psychological effect on the general mass. Therefore, this comprehensive review article encapsulates the biological evolution of human coronaviruses, probable treatment and control strategies to combat COVID-19 and, its impact on human life.

Coronavirus disease 2019 (COVID-19): current status and future perspectives

Coronavirus disease 2019 (COVID-19) originated in the city of Wuhan, Hubei Province, Central China, and has spread quickly to 72 countries to date. COVID-19 is caused by a novel coronavirus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [previously provisionally known as 2019 novel coronavirus (2019-nCoV)]. At present, the newly identified SARS-CoV-2 has caused a large number of deaths with tens of thousands of confirmed cases worldwide, posing a serious threat to public health. However, there are no clinically approved vaccines or specific therapeutic drugs available for COVID-19. Intensive research on the newly emerged SARS-CoV-2 is urgently needed to elucidate the pathogenic mechanisms and epidemiological characteristics and to identify potential drug targets, which will contribute to the development of effective prevention and treatment strategies. Hence, this review will focus on recent progress regarding the structure of SARS-CoV-2 and the characteristics of COVID-19, such as the aetiology, pathogenesis and epidemiological characteristics.

Simplification of Antiretroviral Treatment from Darunavir/Ritonavir Monotherapy to Darunavir/Cobicistat Monotherapy: Effectiveness and Safety in Routine Clinical Practice

Our aim was to evaluate the effectiveness and safety of darunavir/cobicistat (DRV/c) monotherapy as an antiretroviral treatment simplification strategy in HIV-infected patients already on suppressive darunavir/ritonavir (DRV/r) monotherapy in routine clinical practice. We conducted a retrospective multicenter study including all adult patients switched from DRV/r monotherapy to DRV/c monotherapy while HIV-1 RNA was <50 copies/mL and who had at least one follow-up visit. The primary endpoint was the percentage of patients remaining free of treatment failure (TF), defined as discontinuation of monotherapy for any reason, including loss of follow-up. Virological failure (VF) was defined as a confirmed HIV-1 RNA ≥50 copies/mL or any change in the regimen after a single determination with HIV-1 RNA ≥50 copies/mL. Changes in renal function parameters and lipid profile were also evaluated. Factors associated with VF were analyzed using Cox regression. In this study, 173 subjects were included. The median (interquartile range) time of follow-up was 58 (50-67) weeks. Overall, 90% of patients remained free of TF during follow-up. Ten (6%) patients discontinued DRV/c monotherapy for nonvirological reasons and eight (5%) developed VF. No DRV-related mutations were identified in patients with VF. A decrease in triglyceride levels (p = .006) and estimated glomerular filtration rate (p = .005) were observed during follow-up. The presence of blips and CD4+ nadir <100 cells/mm³ were predictors of VF. In conclusion, switching to DRV/c monotherapy seems to be safe and effective in routine clinical practice in HIV-infected patients undergoing suppressive DRV/r monotherapy.

GII.4 Norovirus Protease Shows pH-Sensitive Proteolysis with a Unique Arg-His Pairing in the Catalytic Site

Human noroviruses (NoVs) are the main cause of epidemic and sporadic gastroenteritis. Phylogenetically, noroviruses are divided into seven genogroups, with each divided into multiple genotypes. NoVs belonging to genogroup II and genotype 4 (GII.4) are globally most prevalent. Genetic diversity among the NoVs and the periodic emergence of novel strains present a challenge for the development of vaccines and antivirals to treat NoV infection. NoV protease is essential for viral replication and is an attractive target for the development of antivirals. The available structure of GI.1 protease provided a basis for the design of inhibitors targeting the active site of the protease. These inhibitors, although potent against the GI proteases, poorly inhibit the GII proteases, for which structural information is lacking. To elucidate the structural basis for this difference in the inhibitor efficiency, we determined the crystal structure of a GII.4 protease. The structure revealed significant changes in the S2 substrate-binding pocket, making it noticeably smaller, and in the active site, with the catalytic triad residues showing conformational changes. Furthermore, a conserved arginine is found inserted into the active site, interacting with the catalytic histidine and restricting substrate/inhibitor access to the S2 pocket. This interaction alters the relationships between the catalytic residues and may allow for a pH-dependent regulation of protease activity. The changes we observed in the GII.4 protease structure may explain the reduced potency of the GI-specific inhibitors against the GII protease and therefore must be taken into account when designing broadly cross-reactive antivirals against NoVs.IMPORTANCE Human noroviruses (NoVs) cause sporadic and epidemic gastroenteritis worldwide. They are divided into seven genogroups (GI to GVII), with each genogroup further divided into several genotypes. Human NoVs belonging to genogroup II and genotype 4 (GII.4) are the most prevalent. Currently, there are no vaccines or antiviral drugs available for NoV infection. The protease encoded by NoV is considered a valuable target because of its essential role in replication. NoV protease structures have only been determined for the GI genogroup. We show here that the structure of the GII.4 protease exhibits several significant changes from GI proteases, including a unique pairing of an arginine with the catalytic histidine that makes the proteolytic activity of GII.4 protease pH sensitive. A comparative analysis of NoV protease structures may provide a rational framework for structure-based drug design of broadly cross-reactive inhibitors targeting NoVs.

Second line antiretroviral therapy for treatment of HIV in Asia

Limited access to virological monitoring has led to a high prevalence of resistance to nucleoside reverse transcriptase inhibitors (NRTIs) at the time of first line failure in most studies from low- and middle-income countries (LMIC). Nevertheless, the current standard of care is to include NRTIs in second line regimens. The activity of tenofovir/emtricitabine following failure of stavudine/lamivudine or zidovudine/lamivudine is dependent on the sensitivity of the monitoring strategy used during first line therapy and the threshold for switching, whereas these factors are less important if the opposite sequencing strategy is used. Boosted protease inhibitors (PIs) are the foundation of effective second-line therapy with demonstrated efficacy in early salvage regimens and high barrier to resistance. Lopinavir/ritonavir and ritonavir-boosted atazanavir have recently been described by the World Health Organization as preferred boosted PIs for use in LMIC. Alternative approaches currently under investigation include boosted PI monotherapy, dual boosted PIs, and the combination of raltegravir (an HIV integrase inhibitor) and a boosted PI.

Budget impact analysis of the simplification to atazanavir + ritonavir + lamivudine dual therapy of HIV-positive patients receiving atazanavir-based triple therapies in Italy starting from data of the Atlas-M trial

Background

This analysis aimed at evaluating the impact of a therapeutic strategy of treatment simplification of atazanavir (ATV)+ ritonavir (r) + lamivudine (3TC) in virologically suppressed patients receiving ATV+r+2 nucleoside reverse transcriptase inhibitors (NRTIs) on the budget of the Italian National Health Service (NHS).

Methods

A budget impact model with a 5-year time horizon was developed based on the clinical data of Atlas-M trial at 48 weeks (in terms of percentage of patients experiencing virologic failure and adverse events), from the Italian NHS perspective. A scenario in which the simplification strategy was not considered was compared with three scenarios in which, among a target population of 1,892 patients, different simplification strategies were taken into consideration in terms of percentage of patients simplified on a yearly basis among those eligible for simplification. The costs considered were direct medical costs related to antiretroviral drugs, adverse events management, and monitoring activities.

Results

The percentage of patients of the target population receiving ATV+r+3TC varies among the scenarios and is between 18.7% and 46.9% in year 1, increasing up to 56.3% and 84.4% in year 5. The antiretroviral treatment simplification strategy considered would lead to lower costs for the Italian NHS in a 5-year time horizon between −28.7 million € and −16.0 million €, with a reduction of costs between −22.1% (−3.6 million €) and −8.8% (−1.4 million €) in year 1 and up to −39.9% (−6.9 million €) and −26.6% (−4.6 million €) in year 5.

Conclusion

The therapy simplification for patients receiving ATV+r+2 NRTIs to ATV+r+3TC at a national level would lead to a reduction of direct medical costs over a 5-year period for the Italian NHS.

Evaluation of cerebrospinal fluid virological escape in patients on long-term protease inhibitor monotherapy

BACKGROUND

A strategy of protease inhibitor (PI) monotherapy with re-introduction of triple therapy in those who rebound has been shown to be a safe and effective treatment simplification approach for long-term management. We sought evidence for cerebrospinal fluid (CSF) virological escape in patients on long-term PI monotherapy.

METHODS

We performed lumbar puncture in asymptomatic participants with suppressed plasma HIV RNA after 96 weeks on the PI monotherapy arm (PI-mono) of the PIVOT trial. We also report CSF HIV RNA concentration in trial participants who were investigated for neurological/neurocognitive symptoms during the trial regardless of study arm allocation.

RESULTS

All 11 asymptomatic participants on PI-mono who were tested had undetectable CSF HIV RNA at week 96. One of the three symptomatic participants on PI-mono had CSF HIV RNA of 1,895 copies/ml (undetectable in plasma) and neither of two symptomatic participants on triple therapy had CSF HIV RNA detected.

CONCLUSIONS

CSF virological escape appears rare in asymptomatic patients on PI monotherapy and may not warrant routine CSF monitoring, but patients with symptoms merit more concern.

The Protease Inhibitor Monotherapy Versus Ongoing Triple Therapy (PIVOT) trial: a randomised controlled trial of a protease inhibitor monotherapy strategy for long-term management of human immunodeficiency virus infection

BACKGROUND

Standard-of-care antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection uses a combination of drugs, until now considered essential to minimise treatment failure and development of drug resistance. Protease inhibitors (PIs) are potent with a high genetic barrier to resistance and have the potential for use as monotherapy after viral load (VL) suppression achieved on combination therapy. However, longer-term resistance and toxicity risks are uncertain.

OBJECTIVE

To compare the effectiveness, toxicity profile and cost-effectiveness of PI monotherapy with those of standard-of-care triple therapy in a pragmatic long-term clinical trial.

DESIGN

Open-label, parallel-group, randomised controlled trial.

SETTING

Forty-three HIV clinical centres in the UK NHS.

PARTICIPANTS

HIV-positive adults taking standard combination ART with a suppressed VL for ≥ 6 months.

INTERVENTIONS

Patients were randomised to maintain ongoing triple therapy (OT) or switch to a strategy of physician-selected ritonavir-boosted PI monotherapy (PI-mono), with prompt return to combination therapy in the event of VL rebound.

MAIN OUTCOME MEASURES

The primary outcome was reduction of future drug options, defined as new intermediate-/high-level resistance to one or more drugs to which the patient's virus was considered to be sensitive at trial entry (non-inferiority comparison, 10% margin). Secondary outcomes included confirmed virological rebound, serious drug- or disease-related complications, total grade 3 or 4 adverse events (AEs), neurocognitive function change, cluster of differentiation 4 (CD4) cell count change, change in health-related quality of life, cardiovascular risk change, health-care costs and health economic analysis.

RESULTS

In total, 587 participants were randomised (77% male, 68% white) to OT (n = 291) or PI-mono (n = 296) and followed for a median of 44 months, of whom 2.7% withdrew/were lost to follow-up. One or more episodes of confirmed VL rebound were observed in eight patients (Kaplan-Meier estimate 3.2%) in the OT group and 95 patients (35.0%) in the PI-mono group [absolute risk difference 31.8%, 95% confidence interval (CI) 24.6% to 39.0%; p < 0.001]. PI-mono patients who changed to ART after VL rebound all resuppressed (median 3.5 weeks). The proportions with loss of a future drug option at 3 years were 0.7% in the OT group and 2.1% in the PI-mono group (difference 1.4%, (95% CI -0.4% to 3.4%); non-inferiority demonstrated). There were no significant differences in serious disease complications between groups or in the frequency of grade 3 or 4 clinical AEs (16.8% OT group vs. 22% PI-mono group; absolute risk difference 5.1%, 95% CI -1.3% to 11.5%; p = 0.12). Overall, the PI-mono strategy was shown to be cost-effective compared with OT under most scenarios explored. PI-mono was cost saving because of the large savings in ART drug costs while being no less effective in terms of quality-adjusted life-years in the within-trial analysis and only marginally less effective when extrapolated to lifetime outcomes.

CONCLUSIONS

PI monotherapy, with prompt reintroduction of combination therapy for VL rebound, was non-inferior to combination therapy in preserving future treatment options and is an acceptable and cost-effective alternative for long-term management of HIV infection.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN04857074.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 21. See the NIHR Journals Library website for further project information.

Virological efficacy of PI monotherapy for HIV-1 in clinical practice

BACKGROUND

Clinical trials of PI monotherapy indicate that most participants maintain viral suppression and emergent protease resistance is rare. However, outcomes among patients receiving PI monotherapy for clinical reasons, such as toxicity or adherence issues, are less well studied.

METHODS

An observational study of patients attending an HIV treatment centre in London, UK, who had received PI monotherapy between 2004 and 2013, was conducted using prospectively collected clinical data and genotypic resistance reports. Survival analysis techniques were used to examine the times to virological failure and treatment discontinuation.

RESULTS

Ninety-five patients had PI monotherapy treatment for a median duration of 126 weeks. Virological failure occurred during 64% of episodes and 8% of patients developed emergent protease mutations. We estimate failure occurs in half of episodes within 2 years following initiation. Where PI monotherapy was continued following virological failure, 68% of patients achieved viral re-suppression. Despite a high incidence of virological failure, many patients continued PI monotherapy and 79% of episodes were ongoing at the end of the study. The type of PI used, the presence of baseline protease mutations and the plasma HIV RNA at initiation did not have a significant impact on treatment outcomes.

CONCLUSIONS

There was a higher incidence of virological failure and emerging resistance in our UK clinical setting than described in PI monotherapy clinical trials and other European observational studies. Despite this, many patients continued PI monotherapy and regained viral suppression, indicating this strategy remains a viable option in certain individuals following careful clinical evaluation.

Effect of Monotherapy with Darunavir/Ritonavir on Viral Load in Seminal Fluid, and Quality Parameters of Semen in HIV-1-Positive Patients

Patients with human immunodeficiency virus type 1 (HIV-1) who receive antiretroviral therapy (ART) often achieve increased survival and improved quality of life. In this respect, monotherapy with darunavir/ritonavir (mDRV/r) can be a useful treatment strategy. This prospective study analyses the effect of mDRV/r on sperm quality and viral load in a group of 28 patients who had previously been given conventional ART and who had recorded a viral load <20 copies/mL for at least six months. These patients were given mDRV/r at a dose of 800/100 mg for 48 weeks. At baseline (V0), CD4, CD8, FSH, LH and testosterone levels were measured, together with HIV-1 viral load in plasma and semen. In addition, seminal fluid quality was studied before mDRV/r treatment was prescribed. At week 48 (V1), HIV-1 viral load in plasma and semen and the quality of the seminal fluid were again measured. The results obtained indicate that at V0, 10% of the patients with ART had a positive viral load in seminal fluid (>20 copies/ml), and that at V1, after mDRV/r treatment, this figure had fallen to 3%. The quality of seminal fluid was close to normal in 57% of patients at V0 and in 62% at V1. We conclude that, similar to ART, mDRV/r maintains HIV-1 viral load in most patients, and that there is no worsening in seminal fluid quality.

Cerebrospinal fluid analysis for HIV replication and biomarkers of immune activation and neurodegeneration in long-term atazanavir/ritonavir monotherapy treated patients

BACKGROUND

Cerebrospinal fluid (CSF) viral escape is a concern in ritonavir-boosted protease inhibitors monotherapy. The aim was to assess HIV-RNA, biomarkers of immune activation and neurodegeneration, and atazanavir concentrations in CSF of patients on successful long-term atazanavir/ritonavir (ATV/r) monotherapy.

METHODS

This is a substudy of the multicentric, randomized, open-label, noninferiority trial monotherapy once a day with atazanavir/ritonavir (NCT01511809), comparing the ongoing ATV/r along with 2 nucleoside retrotranscriptase inhibitors (NRTIs) regimen to a simplified ATV/r monotherapy. Patients with plasma HIV-RNA < 50 copies/mL after at least 96 study weeks were eligible.We assessed HIV-RNA, soluble (s)CD14, sCD163, CCL2, CXCL10, interleukin-6, and YKL40 by enzyme-linked immunosorbent assay; neopterin, tryptophan, kynurenine, and neurofilament by immunoassays; and ATV concentrations by liquid chromatography-mass spectrometry in paired plasma and CSF samples. Variables were compared with Wilcoxon rank-sum or Fisher exact test, as appropriate.

RESULTS

HIV-RNA was detected in the CSF of 1/11 patients on ATV/r monotherapy (114 copies/mL), without neurological symptoms, who was successfully reintensified with his previous 2NRTIs, and in none of the 12 patients on ATV/r + 2NRTIs. CSF biomarkers and ATV concentrations did not differ between the 2 arms.

CONCLUSIONS

CSF escape was uncommon in patients on long-term ATV/r monotherapy and was controlled with reintensification.

Short Communication: Efficacy and Safety of Treatment Simplification to Lopinavir/Ritonavir or Darunavir/Ritonavir Monotherapy: A Randomized Clinical Trial

Antiretroviral treatment simplification strategies based on monotherapy with darunavir/ritonavir (DRV/r) or lopinavir/ritonavir (LPV/r) have not been directly compared in clinical trials. We evaluated the 48-week efficacy and safety of DRV/r versus LPV/r monotherapy as a treatment simplification strategy in a multicenter, randomized open-label study. Maintenance of viral suppression in cerebrospinal fluid (CSF) and semen was also explored. An intention to treat efficacy analysis was performed considering missing equals to failure (ITT:M = F). Virological failure (VF) was defined as a confirmed increase in plasma HIV-1 RNA >50 copies/mL. A total of 75 patients were enrolled: 40 were allocated to DRVr and 33 to LPVr. In the ITT: M = F analysis, 77.5% of patients on DRV/r and 66.6% of patients on LPV/r maintained HIV-1 RNA <50 copies/mL at week 48 (p = .302, treatment difference 10.8% [95% CI,-12.6 to 34.2]). In the DRV/r arm, no patients developed VF and 15.0% discontinued treatment due to adverse events. In the LPV/r arm, 2 (6.1%) patients developed VF and 18.2% discontinued monotherapy due to adverse events. Gastrointestinal disturbances were experienced by 18.2% and 2.5% of patients in the LPV/r and DRV/r arms, respectively (p = .019). Two patients had detectable HIV-1 RNA ≥50 copies/mL in CSF or semen. Monotherapy with LPV/r or DRV/r seems to be virologically effective in selected HIV-1-infected patients with sustained viral suppression. Differences between both regimens seem driven mainly by the better tolerability profile of DRV/r.

Dolutegravir as maintenance monotherapy: first experiences in HIV-1 patients

BACKGROUND

Dolutegravir is recommended as part of combination ART (cART) for HIV-1-infected patients. Toxicities, drug interactions and costs related to cART still warrant the search for improved treatment options. Dolutegravir's high resistance barrier might make it suitable as antiretroviral maintenance monotherapy. The feasibility of this strategy is currently unknown.

METHODS

This is a prospective case series on five consecutive HIV-1-infected patients on cART without previous virological failure who switched to dolutegravir monotherapy. All were HIV-RNA suppressed <50 copies/mL and had contraindications to current and alternative combinations of antiretroviral drugs. HIV-RNA was measured at baseline, week 4, week 8, week 12 and every 6 weeks thereafter. Patients would be switched back to their original cART upon confirmed HIV-RNA >50 copies/mL.

RESULTS

The five patients had been HIV-RNA suppressed <50 copies/mL for ≥1.5 years prior to the initiation of dolutegravir monotherapy. All were on NNRTI-containing regimens at the switch. HIV-RNA remained <50 copies/mL at all timepoints in four patients. One patient, with end-stage renal disease and on calcium supplements, had a pre-cART HIV-RNA of 625 000 copies/mL with a CD4 nadir of 120 cells/mm(3) and had HIV-RNA of 8150 copies/mL at week 30. The dolutegravir Ctrough was 0.18 mg/L. This patient did not have acquired resistance or evidence of adherence problems and HIV-RNA was resuppressed after switching to his former cART.

CONCLUSIONS

This case series indicates that dolutegravir monotherapy might be a valuable maintenance option in selected HIV-infected patients who are well suppressed on cART, if confirmed by future randomized clinical trials.

Efficacy of protease inhibitor monotherapy vs. triple therapy: meta-analysis of data from 2303 patients in 13 randomized trials

OBJECTIVES

The aim of this analysis was to review the evidence and update a meta-analysis evaluating the efficacy and safety results from randomized controlled trials of ritonavir-boosted protease inhibitor (PI/r) monotherapy.

METHODS

A PubMed/EMBASE search was conducted to find randomized trials of PI/r monotherapy vs. triple therapy in patients with HIV-1 RNA suppression at baseline (<50 HIV-1 RNA copies/mL). Rates of virological suppression were analysed using switch-equals-failure and intensification-included endpoints [intent-to-treat (ITT)]. The rate of treatment-emergent resistance mutations, neurocognitive function endpoints, and cerebrospinal fluid (CSF) HIV-1 RNA were also analysed by treatment arm.

RESULTS

There were 2303 patients from 13 different randomized clinical trials of darunavir/r monotherapy (n = 784: MONET, MONOI, Monarch and PROTEA), lopinavir/r monotherapy (n = 829: OK pilot, OK-04, KalMo, KALESOLO, KRETA, MOST and DREAM), atazanavir/r monotherapy (n = 103: MODAT), or all three (n = 587: PIVOT). HIV-1 RNA plasma suppression was lower in the PI/r monotherapy arm compared with the triple therapy arm in the switch-equals-failure analysis [difference -8.3%; 95% confidence interval (CI) -11.9 to -4.8%], but not when intensification was included (difference 0.5%; 95% CI -2.5 to 3.6%). Rates of resistance mutations were similar between arms, as was overall neurocognitive function.

CONCLUSIONS

PI/r monotherapy showed a higher risk of plasma HIV-1 RNA elevations. However, there was no increased risk of treatment-emergent drug resistance, neurocognitive endpoints did not differ, and HIV-1 RNA suppression rates after intensification were similar between PI/r monotherapy and triple therapy.

Week 120 efficacy of tenofovir, lamivudine and lopinavir/r-based second-line antiretroviral therapy in treatment-experienced HIV patients

BACKGROUND

Tenofovir (TDF) and ritonavir-boosted lopinavir (LPV/r) were not introduced to China as second-line medications until 2009. The efficacy and safety of TDF/3TC/LPV/r based second-line regimen have not been evaluated in Chinese HIV patients who failed first-line regimens.

METHODS

This was a multicenter cohort study recruiting patients from Beijing, Shanghai, Guangdong, and Henan provinces between November 2008 and January 2010. Eighty HIV infected patients failing first-line regimens with serum creatinine lower than 1.5 times the upper limit of normal received TDF+ lamivudine (3TC)+ LPV/r were followed up for 120 weeks. CD4 cell count, viral load, and estimated glomerular filtration rate (eGFR) were monitored at each visit.

RESULTS

At baseline, 31.2% and 48.8% of patients had moderate/high-level resistance to TDF and 3TC, respectively; while 2.5% of patients had only low-level resistance to LPV/r. During 120 weeks of follow-up, virological suppression rate reached over 70% (<40 copies/ml) and 90% (<400 copies/ml), and median CD4 cell count increased from 157 cells/μL at baseline to 307 cells/μL at week 120. Baseline drug-resistance mutations had no impact on the efficacy of second-line antiretroviral therapy. Median eGFR dropped from 104.7 ml/min/1.73m2 at baseline to 95.6 ml/min/1.73m2 at week 24 and then recovered after week 96.

CONCLUSION

This study for the first time demonstrated that TDF+ 3TC+ LPV/r was efficacious as second-line regimen with acceptable nephrotoxicity profiles in patients who failed zidovudine or stavudine based first-line regimens in China.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00872417.

Ritonavir-boosted lopinavir as maintenance monotherapy in HIV-infected patients who achieved viral suppression during a second-line protease inhibitor-based regimen: a pilot randomized trial (BIDI-MONO)

Eligibility criteria were (I) having previously failed first-line nonnucleoside reverse transcriptase inhibitor-based regimens and (2) having achieved virologic suppression >6 months while receiving a protease inhibitor (PI)-based regimen as second-line treatment. Eligible participants were randomized to receive either (I) ritonavir-boosted lopinavir (LPV/r) monotherapy (n = 29) or (2) LPV/r with optimized background regimens (OBRs; n = 31). Median duration of viral suppression before randomization was 45 months. At week 48, viral suppression during LPV/r monotherapy was 86.2% and did not differ from the suppression achieved with LPV/r with OBRs (87.1%, P = 1.000). However, persistent viremia during LPV/r monotherapy tended to be higher than during LPV/r with OBRs (10.3% versus 3.2%, P = .346). History of viral blip during virologic suppression with second-line PI-based regimen is a predictor of achieving viral suppression at all visits (adjusted relative risk 0.255 [95% confidence interval 0.080-0.821], P = .022). Use of LPV/r monotherapy as maintenance regimen in this study produced persistent viremia that tended to be higher than LPV/r monotherapy with OBRs.

Monotherapy with boosted PIs as an ART simplification strategy in clinical practice

BACKGROUND

Data on the efficacy of simplifying therapy using darunavir/ritonavir and lopinavir/ritonavir monotherapy in clinical practice remain limited.

METHODS

A retrospective single-centre study including patients initiating darunavir/ritonavir or lopinavir/ritonavir monotherapy with a plasma HIV-1 viral load (pVL) <50 copies/mL and at least one subsequent follow-up visit. The primary endpoint was the percentage of patients remaining free of virological failure (VF; defined as a confirmed pVL >50 copies/mL or as any change in the regimen after a single determination with a pVL >50 copies/mL) during the follow-up. We also evaluated the percentage of patients remaining free of treatment failure (TF; defined as VF or the early discontinuation of monotherapy for any reason) and compared the effectiveness of the two regimens. Effectiveness was evaluated using cumulative survival analysis (at Weeks 48 and 96). Factors associated with VF and TF were analysed using Cox regression.

RESULTS

A total of 522 patients were included (309 receiving lopinavir/ritonavir and 213 receiving darunavir/ritonavir). The median follow-up was 64.3 (30.5-143.0) weeks. The percentage of patients free of VF and TF was 94% (95% CI 91%-96%) and 79% (95% CI 75%-82%) at 48 weeks, respectively, and 86% (95% CI 81%-89%) and 62% (95% CI 57%-67%) at 96 weeks, respectively. The risk of VF was similar for the two regimens (HR=1.0, 95% CI 0.6-1.8; P=0.962). Lopinavir/ritonavir monotherapy was associated with a 1.5-fold greater risk of TF (95% CI 1.1-2.1; P=0.012) and a 2.3-fold greater risk of discontinuation of therapy due to adverse events (95% CI 1.3-3.9; P=0.003).

CONCLUSIONS

The virological efficacy of darunavir/ritonavir and lopinavir/ritonavir monotherapy is high in clinical practice. Treatment discontinuation due to safety issues is more frequent with lopinavir/ritonavir.

Short communication: focal encephalitis related to viral escape and resistance emergence in cerebrospinal fluid in a patient on lopinavir/ritonavir monotherapy with plasma HIV-1 RNA suppression

Monotherapy with boosted protease inhibitors has emerged as an antiretroviral therapy simplification alternative for selected patients, endorsed by the results of some randomized clinical trials. However, there are some concerns about the efficacy of such a strategy in achieving successful viral suppression in those anatomic compartments or reservoirs in which antiretroviral drug penetration is lower, such as the central nervous system (CNS). Several studies have demonstrated better neurocognitive performance in patients receiving antiretroviral drugs with better cerebrospinal fluid (CSF) penetration. Nevertheless, cases of CSF viral escape accompanied by moderate or severe neurological symptoms have been reported with both standard triple therapy and boosted protease inhibitor (PI) monotherapy, and it is not well established whether ritonavir-boosted protease inhibitor (PI/r) monotherapy is associated with a higher risk of symptomatic CSF viral escape or not. Herein, we present a case of viral rebound and resistance emergence exclusively in CSF associated with an unusual clinical manifestation of focal encephalitis in a patient with plasma HIV-1 RNA suppression while receiving lopinavir/ritonavir monotherapy. Clinical resolution and CSF viral suppression were observed after switching to a genotype-guided combined antiretroviral regimen with good CSF penetration.

Simplification to atazanavir/ritonavir monotherapy for HIV-1 treated individuals on virological suppression: 48-week efficacy and safety results

OBJECTIVES

The objective of this study was to assess the 48-week virological efficacy of atazanavir/ritonavir (ATV/r) monotherapy vs. ATV/r along with two nucleoside reverse transcriptase (NRTIs) in HIV-1 treated individuals with HIV-RNA less than 50 copies/ml.

METHODS

A multicentre, randomized, open-label, noninferiority trial. HIV-1 treated individuals on ATV/r 300/100 mg along with two NRTIs were randomized to receive ATV/r monotherapy or to maintain their antiretroviral regimen. The primary endpoint was the confirmed viral rebound (CVR: two consecutive HIV-RNA >50 copies/ml) or treatment discontinuation for any reason. Individuals who experienced CVR on ATV/r monotherapy reintroduced NRTIs and discontinued the study if HIV-RNA was more than 50 copies/ml after 12 weeks since reintensification.

RESULTS

One hundred and three patients enrolled. By week 48, 11 patients in ATV/r arm and two in ATV/r along with two NRTIs experienced CVR; four (8%) patients in ATV/r and eight (15%) in ATV/r along with two NRTIs discontinued. At the 48-week primary efficacy analysis (re-intensification = failure), treatment success was 73% in ATV/r arm and 85% in ATV/r along with two NRTIs [difference -12.1%, 95% confidence interval (95% CI) -27.8 to 2.1]. According to the analysis considering re-intensification is equal to success, treatment success was 92% in ATV/r arm and 85% in the ATV/r along with two NRTIs arm (difference 7.5%, 95% CI -4.7 to 19.8). At CVR, no mutation was observed in ATV/r arm and reintensification with NRTIs was effective in all individuals. Overall, Grade 3-4 (P = 0.003) and grade 3-4 drug-related (P = 0.027) adverse events were less frequent in ATV/r arm. A significant increase in total and low-density lipoprotein (LDL)-cholesterol was observed as well as a significant improvement in high-density lipoprotein (HDL)-cholesterol, fasting glucose, liver fibrosis and alkaline phosphatase was observed in ATV/r monotherapy in comparison with ATV/r along with two NRTIs.

CONCLUSION

ATV/r monotherapy treatment simplification showed lower virological efficacy in comparison with maintaining triple therapy; NRTIs reintroduction was effective in all the individuals.

Budget impact analysis of antiretroviral less drug regimen simplification in HIV-positive patients on the Italian National Health Service

Background

Deintensification and less drug regimen (LDR) antiretroviral therapy (ART) strategies have proved to be effective in terms of maintaining viral suppression in human immunodeficiency virus (HIV)-positive patients, increasing tolerability, and reducing toxicity of antiretroviral drugs administered to patients. However, the economic impact of these strategies have not been widely investigated. The aim of the study is to evaluate the economic impact that ART LDR could have on the Italian National Health Service (INHS) budget.

Methods

A budget impact model was structured to assess the potential savings for the INHS by the use of ART LDR for HIV-positive patients with a 3 year perspective. Data concerning ART cost, patient distribution within different ARTs, and probabilities for patients to change ART on a yearly basis were collected within four Italian infectious diseases departments, providing ART to 13.7% of the total number of patients receiving ART in Italy.

Results

The LDR investigated (protease inhibitor-based dual and monotherapies) led to savings for the hospitals involved when compared to the “do nothing” scenario on a 3 year basis, between 6.7% (23.11 million €) and 12.8% (44.32 million €) of the total ART expenditures. The mean yearly cost per patient is reduced from 9,875 € in the do nothing scenario to a range between 9,218 € and 8,615 €. The use of these strategies within the four departments involved would have led to a reduction of ART expenditures for the INHS of between 1.1% and 2.1% in 3 years.

Conclusion

ART LDR simplification would have a significant impact in the reduction of ART-related costs within the hospitals involved in the study. These strategies could therefore be addressed as a sustainable answer to the public financing reduction observed within the INHS in the last year, allowing therapies to be dispensed without affecting the quality of the services provided.

Phenotypic characterization of virological failure following lopinavir/ritonavir monotherapy using full-length Gag-protease genes

Objectives

Major protease mutations are rarely observed following first-line failure with PIs and interpretation of genotyping results in this context may be difficult. We performed extensive phenotyping of viruses from five patients failing lopinavir/ritonavir monotherapy in the MONARK study without major PI mutations by standard genotyping.

Methods

Phenotypic susceptibility testing and viral infectivity assessments were performed using a single-cycle assay and fold changes (FC) relative to a lopinavir-susceptible reference strain were calculated.

Results

>10-fold reduced baseline susceptibility to lopinavir occurred in two of five patients and >5-fold in another two. Four of five patients exhibited phylogenetic evidence of a limited viral evolution between baseline and failure, with amino acid changes at drug resistance-associated positions in one: T81A emerged in Gag with M36I in the protease gene, correlating with a reduction in lopinavir susceptibility from FC 7 (95% CI 6–8.35) to FC 13 (95% CI 8.11–17.8). Reductions in darunavir susceptibility (>5 FC) occurred in three individuals.

Discussion

This study suggests both baseline reduced susceptibility and evolution of resistance could be contributing factors to PI failure, despite the absence of classical PI resistance mutations by standard testing methods. Use of phenotyping also reveals lower darunavir susceptibility, warranting further study as this agent is commonly used following lopinavir failure.

Protease inhibitor monotherapy is not associated with increased viral replication in lymph nodes

There are concerns about residual viremia in sanctuary sites among patients on protease inhibitor monotherapy, so we aimed to study viro-immunological parameters in tonsil's lymphoid tissue of patients on highly active antiretroviral therapy (HAART) and on protease inhibitor monotherapy. Despite fully suppressed serum HIV viral load, we found viral replication in both groups; in addition, more patients had detectable proviral DNA among those on HAART, compared to those on protease inhibitor monotherapy (P = 0.08), supporting the absence of a deleterious effect of protease inhibitor monotherapy.

Switch strategies in antiretroviral therapy regimens

Despite great advances in antiretroviral therapy in the last decade, several limitations still remain such as adverse effects, lack of adherence and drug-drug interactions. Switching antiretroviral therapy in stable, virologically suppressed patients with the aim of improving tolerability and convenience is an expanding strategy in clinical practice. Several factors need to be taken into consideration when switching a suppressive regimen, such as previous virologic failure, genetic barrier of the new regimen, prior duration of virologic suppression and expected level of adherence. The most frequently used strategies include reductions in the number of pills, drugs or doses. Although switching strategies may be useful, not all the regimens used in clinical practice are based on data from randomized clinical trials and some may not be the best option for certain patients; therefore, therapy should be individualized taking into consideration available information as well as patient and drug characteristics.

When can HIV clinical trials detect treatment effects on drug resistance?

Methods of sampling patients for resistance testing, and statistical analyses of HIV drug resistance, have not been standardised in HIV clinical trials. We analysed methods of genotyping and rates of treatment-emergent drug resistance from 27 clinical trials identified from a MEDLINE search. Sample size calculations were conducted using NQUERY software, assuming 5% significance level, 80% power and 1:1 randomisation. The percentage of patients with treatment-emergent IAS-USA mutations after 96 weeks ranged from 1.8% to 9.1% for first-line 2NRTI/NNRTI treatments, 0.6% to 6.3% for first-line 2NRTI/PI/r treatments and 0.0% to 2.0% in switch trials of boosted PIs. The prevalence of drug resistance was higher in trials with no screening for drug resistance at baseline, where the HIV RNA cut-off for genotyping was >50 copies/mL, where patients were tested for drug resistance after discontinuation of treatment, and where follow-up times were 96 weeks or longer. HIV clinical trials could be designed to detect differences in the risk of HIV drug resistance between treatments, as an analysis supporting HIV RNA suppression as the primary endpoint. However, this would require a standardised approach, with intent-to-treat analyses, testing of all samples with HIV RNA>50 copies/mL and genotyping after drug discontinuation.

Baseline natural killer and T cell populations correlation with virologic outcome after regimen simplification to atazanavir/ritonavir alone (ACTG 5201)

Objectives

Simplified maintenance therapy with ritonavir-boosted atazanavir (ATV/r) provides an alternative treatment option for HIV-1 infection that spares nucleoside analogs (NRTI) for future use and decreased toxicity. We hypothesized that the level of immune activation (IA) and recovery of lymphocyte populations could influence virologic outcomes after regimen simplification.

Methods

Thirty-four participants with virologic suppression ≥48 weeks on antiretroviral therapy (2 NRTI plus protease inhibitor) were switched to ATV/r alone in the context of the ACTG 5201 clinical trial. Flow cytometric analyses were performed on PBMC isolated from 25 patients with available samples, of which 24 had lymphocyte recovery sufficient for this study. Assessments included enumeration of T-cells (CD4/CD8), natural killer (NK) (CD3⁺CD56⁺CD16⁺) cells and cell-associated markers (HLA-DR, CD's 38/69/94/95/158/279).

Results

Eight of the 24 patients had at least one plasma HIV-1 RNA level (VL) >50 copies/mL during the study. NK cell levels below the group median of 7.1% at study entry were associated with development of VL >50 copies/mL following simplification by regression and survival analyses (p = 0.043 and 0.023), with an odds ratio of 10.3 (95% CI: 1.92–55.3). Simplification was associated with transient increases in naïve and CD25⁺ CD4⁺ T-cells, and had no impact on IA levels.

Conclusions

Lower NK cell levels prior to regimen simplification were predictive of virologic rebound after discontinuation of nucleoside analogs. Regimen simplification did not have a sustained impact on markers of IA or T lymphocyte populations in 48 weeks of clinical monitoring.

Trial Registration

ClinicalTrials.gov NCT00084019

Pattern of neurocognitive function in patients receiving boosted protease inhibitor monotherapy: a detailed neuropsychological study

It is unknown if, compared to a triple drug antiretroviral therapy, boosted protease inhibitor monotherapy leads to worse results in specific neuropsychological processes. In our study, we included patients virologically suppressed (≥1 year), on antiretroviral therapy, without concomitant major neurocognitive confounders, receiving boosted lopinavir or darunavir as monotherapy (n = 96) or as triple therapy with two nucleoside reverse transcriptase inhibitors (n = 95). All patients underwent a comprehensive neuropsychological test battery (14 neuropsychological measures, covering seven domains). Both groups were compared in average score distributions and rates of neuropsychological deficits. Similar comparisons were conducted only for patients with neurocognitive impairment. In the adjusted analysis, we found only small differences between groups in the entire sample: better verbal learning (p = 0.02; d = 0.28) and verbal recall scores (p < 0.01; d = 0.25) in patients on boosted protease inhibitor monotherapy and slightly better motor skills with dominant hand (p = 0.02; d = 0.23) scores in patients on triple therapy. No greater proportion of deficits in the protease inhibitor monotherapy group was found in any neuropsychological measure. In neurocognitively impaired patients, we found similar outcomes in verbal learning, verbal recall, and motor skills with dominant hand but with larger effect sizes. Close similarities in the neurocognitive pattern between groups question the clinical relevance of the number of neuroactive drugs included in the regimen. These results also suggest that peripheral viral load control may be a good indicator of brain protection.

Immune activation throughout a boosted darunavir monotherapy simplification strategy

Our aim was to assess the evolution and the impact that blips, intermittent low-level viraemia and virological failure (VF) episodes have on patients' immune activation (IA) profiles during ritonavir-boosted darunavir monotherapy (mtDRV/rtv). A prospective cohort of human immunodeficiency virus-1-infected patients who switched to mtDRV/rtv was followed for 2 years. Cellular IA was assessed according to HLA-DR and CD38 expression in CD4(+) and CD8(+) T-cells and their naïve, effector memory and central memory subpopulations, and systemic IA was evaluated according to sCD14 and D-dimer levels. Seventy-five patients from the MonDAR cohort were selected for this substudy, and classified according to viral outcome as having continuous undetectable viraemia (n = 19), blips (n = 19), intermittent viraemia (n = 21), and VF (n = 16). The IA profile was closely linked to viral behaviour. Patients on viral suppression for 24 months showed a significant decrease in CD4(+) and CD8(+) T-cell activation and sCD14 and D-dimer levels. Patients with transient low-level viraemia episodes (blips and intermittent viraemia) showed cellular and systemic IA similar to baseline values. In contrast, significant increases in T-cell activation and sCD14 and D-dimer levels were observed in patients with VF. Baseline levels of HLA-DR(+)CD38(+)CD8(+) T-cells of >6.4% were independently associated with the emergence of VF. Therefore, mtDRV/rtv might be considered as a safe simplification strategy, on the basis of the IA results, whenever viral replication is under medium-term and long-term control. Transient low-level viraemia episodes do not affect patients' IA status. Moreover, HLA-DR(+)CD38(+)CD8(+) T-cell baseline levels should be considered when patients are switched to mtDRV/rtv.

Cellular HIV reservoir replenishment is not affected by blip or intermittent viremia episodes during darunavir/ritonavir monotherapy

OBJECTIVE

To assess the impact of blips and persistent viremia episodes on cell-associated HIV-DNA reservoir in extensively pretreated patients receiving ritonavir-boosted darunavir monotherapy (MtDRV/rtv) for 24 months.

DESIGN AND METHODS

Patients from the MonDAR prospective study (NCT01606722) who received at least 6 months of MtDRV/rtv and had at least two available peripheral blood mononuclear cells (PBMCs) samples were selected and classified according to the viral outcome as continuous undetectable viremia (cUV; n = 40), blips (n = 31), intermittent viremia (IV; n = 23), and virological failure (VF, two consecutive viral loads >200 copies/ml; n = 20). Proviral HIV-DNA was quantified by real-time PCR in PBMCs samples at baseline, and months 6, 12, 18 and 24. Additionally, HIV-DNA levels were exhaustively analyzed at virological failure and blip episodes.

RESULTS

The HIV-DNA levels remained constant during the 24 months in every group. Neither blips nor intermittent viremia influenced the HIV-DNA levels at short-term or at middle term. By contrast, virological failure episodes gave rise to a significant increase in proviral DNA (2.15 vs. 2.32 log10 HIV-DNA copies/10 PBMCs; P = 0.042). Basal proviral DNA levels more than 2 log10 copies/10 PBMCs predicted the time to viral rebound at any given cut-off point (>20, >50, and >200 copies/ml. HR: 3.02, 2.61, and 3.02, respectively; P ≤ 0.03. Besides, an adherence less than 95% was also strongly associated with virological failure (HR, 3.17; P = 0.021).

CONCLUSION

Blip episodes and intermittent viremia did not affect the cellular HIV reservoir dynamic during MtDRV/rtv. Higher adherence and an HIV-DNA levels less than 2 log10 copies/10 PBMCs at baseline were associated with a lower risk of virological failure.

[Consensus Statement by GeSIDA/National AIDS Plan Secretariat on antiretroviral treatment in adults infected by the human immunodeficiency virus (Updated January 2013)]

OBJECTIVE

This consensus document is an update of combined antiretroviral therapy (cART) guidelines for HIV-1 infected adult patients.

METHODS

To formulate these recommendations a panel composed of members of the GeSIDA/National AIDS Plan Secretariat (Grupo de Estudio de Sida and the Secretaría del Plan Nacional sobre el Sida) reviewed the efficacy and safety advances in clinical trials, cohort and pharmacokinetic studies published in medical journals (PubMed and Embase) or presented in medical scientific meetings. The strength of the recommendations and the evidence which support them are based on a modification of the criteria of Infectious Diseases Society of America.

RESULTS

cART is recommended in patients with symptoms of HIV infection, in pregnant women, in serodiscordant couples with high risk of transmission, in hepatitisB co-infection requiring treatment, and in HIV nephropathy. cART is recommended in asymptomatic patients if CD4 is <500cells/μl. If CD4 are >500cells/μl cART should be considered in the case of chronic hepatitisC, cirrhosis, high cardiovascular risk, plasma viral load >100.000 copies/ml, proportion of CD4 cells <14%, neurocognitive deficits, and in people aged >55years. The objective of cART is to achieve an undetectable viral load. The first cART should include 2 reverse transcriptase inhibitors (RTI) nucleoside analogs and a third drug (a non-analog RTI, a ritonavir boosted protease inhibitor, or an integrase inhibitor). The panel has consensually selected some drug combinations, for the first cART and specific criteria for cART in acute HIV infection, in tuberculosis and other HIV related opportunistic infections, for the women and in pregnancy, in hepatitisB or C co-infection, in HIV-2 infection, and in post-exposure prophylaxis.

CONCLUSIONS

These new guidelines update previous recommendations related to first cART (when to begin and what drugs should be used), how to monitor, and what to do in case of viral failure or adverse drug reactions. cART specific criteria in comorbid patients and special situations are similarly updated.

Accumulation of protease mutations among patients failing second-line antiretroviral therapy and response to salvage therapy in Nigeria

BACKGROUND

To date, antiretroviral therapy (ART) guidelines and programs in resource-limited settings (RLS) have focused on 1(st)- and 2(nd)-line (2 L) therapy. As programs approach a decade of implementation, policy regarding access to 3(rd)-line (3 L) ART is needed. We aimed to examine the impact of maintaining patients on failing 2 L ART on the accumulation of protease (PR) mutations.

METHODS AND FINDINGS

From 2004-2011, the Harvard/APIN PEPFAR Program provided ART to >100,000 people in Nigeria. Genotypic resistance testing was performed on a subset of patients experiencing 2 L failure, defined as 2 consecutive viral loads (VL)>1000 copies/mL after ≥6 months on 2 L. Of 6714 patients who received protease inhibitor (PI)-based ART, 673 (10.0%) met virologic failure criteria. Genotypes were performed on 61 samples. Patients on non-suppressive 2 L therapy for <12 months prior to genotyping had a median of 2 (IQR: 0-5) International AIDS Society (IAS) PR mutations compared with 5 (IQR: 0-6) among patients failing for >24 months. Patients developed a median of 0.6 (IQR: 0-1.4) IAS PR mutations per 6 months on failing 2 L therapy. In 38% of failing patients no PR mutations were present. For patients failing >24 months, high- or intermediate-level resistance to lopinavir and atazanavir was present in 63%, with 5% to darunavir.

CONCLUSIONS

This is the first report assessing the impact of duration of non-suppressive 2 L therapy on the accumulation of PR resistance in a RLS. This information provides insight into the resistance cost of failing to switch non-suppressive 2 L regimens and highlights the issue of 3 L access.

Durability of lopinavir/ritonavir monotherapy in individuals with viral load ≤50 copies/ml in an observational setting

BACKGROUND

The main objective is to evaluate the efficacy and durability of lopinavir-ritonavir monotherapy (LPV/r-MT) in virologically controlled HIV-positive individuals switching from combination antiretroviral therapy (cART).

METHODS

Criteria to be included in this observational study were to have initiated for the first time LPV/r-MT after ≥2 consecutive HIV RNA≤50 copies/ml achieved on a ≥3-drug-including regimen. The main end points were time to virological rebound (VR; defined in two ways: time of first of two consecutive viral load [VL]>50 and >200 copies/ml), time to discontinuation/intensification and time to experience either a single VL>200 copies/ml or discontinuation/intensification (treatment failure [TF]). Individuals' follow-up accrued from the date of starting LPV/r-MT to event or last available VL. Kaplan-Meier curves and Cox regression analyses were used.

RESULTS

A total of 228 individuals were included: median age 46 years (IQR 40-50), 36% females, 36% intravenous drug users and 25% HCV-coinfected. Median CD4(+) T-cell count at nadir was 215 cell/mm(3) (IQR 116-336) and at baseline was 615 cell/mm(3) (IQR 436-768). By 36 months after switching to LPV/r-MT, the proportion of individuals with VR (confirmed VL>200 copies/ml) was 11% and with TF was 35%. In the multivariable Cox model the factors associated with a lower risk of TF was the duration of viral suppression <50 copies/ml prior to baseline (ARH=0.92; 95% CI 0.85, 0.99; P=0.024, per 6 months longer) and having LPV/r as part of last cART (ARH=0.45; 95% CI 0.21, 0.95; P=0.037).

CONCLUSIONS

In daily clinical practice, we confirm a relatively safe approach of treatment simplification to LPV-MT in a selected population with long-lasting virological control.

Virological efficacy in cerebrospinal fluid and neurocognitive status in patients with long-term monotherapy based on lopinavir/ritonavir: an exploratory study

BACKGROUND

Data on suppression of HIV replication in the CNS and on the subsequent risk of neurocognitive impairment using monotherapy with boosted protease inhibitors are limited.

METHODS

Ours was an exploratory cross-sectional study in patients on lopinavir/ritonavir-based monotherapy (LPV/r-MT) or standard triple therapy (LPV/r-ART) for at least 96 weeks who maintained a plasma viral load <50 copies/mL. HIV-1 RNA in CSF was determined by HIV-1 SuperLow assay (lower limit of detection, 1 copy/mL). Neurocognitive functioning was assessed using a recommended battery of neuropsychological tests covering 7 areas. Neurocognitive impairment (NCI) was determined and also a global deficit score (GDS) for study comparisons.

RESULTS

Seventeen patients on LPV/r-MT and 17 on LPV/r-ART were included. Fourteen (82.4%) patients on LPV/r-MT and 16 (94.1%) on LPV/r-ART had HIV-1 RNA <1 copy/mL in CSF (p = 0.601). NCI was observed in 7 patients on LPV/r-MT and in 10 on LPV/r-ART (41% vs 59%; p = 0.494). Mean (SD) GDS was 0.22 (0.20) in patients on LPV/r-MT and 0.47 (0.34) in those on LPV/r-ART (p = 0.012).

CONCLUSIONS

Suppression of HIV in CSF is similar in individuals with durable plasma HIV-1 RNA suppression who are receiving LPV/r-MT or LPV/r-ART for at least 96 weeks. Findings for HIV-1 replication in CSF and neurocognitive status indicate that this strategy seems to be safe for CNS functioning.

Lopinavir plasma concentrations and virological outcome with lopinavir-ritonavir monotherapy in HIV-1-infected patients

There is significant intra- and intersubject variability in lopinavir (LPV) plasma concentrations after standard dosing; thus, this prospective study was conducted to determine whether low plasma LPV concentrations could be associated with virological outcome throughout lopinavir-ritonavir maintenance monotherapy (mtLPVr) in the clinical practice setting. If this hypothesis would be confirmed, LPV drug monitoring could improve the efficacy of mtLPVr regimens. Patients with previous virological failure (VF) on protease inhibitor-based regimens were also included if the genotypic resistance tests showed no major resistance mutation associated with reduced susceptibility to lopinavir-ritonavir. VF was defined as 2 consecutive determinations of HIV RNA levels of >200 copies/ml. Efficacy was analyzed by per-protocol analysis. Plasma LPV trough concentrations were measured by high-performance liquid chromatography using a UV detector. A total of 127 patients were included (22% with previous failure on protease inhibitors). After 96 weeks, the efficacy rate was 82.3% (95% confidence interval [CI(95)], 75.3 to 89.3%). Virological efficacy was independent of LPV plasma concentrations even when LPVr was given once daily. An adherence of <90% (HR, 4.4 [CI(95), 1.78 to 10.8; P = 0.001]) and the presence of blips in the preceding 12 months (HR, 3.06 [CI(95), 1.17 to 8.01; P = 0.022]) were the only variables independently associated with time to VF. These findings suggest that the LPV concentrations achieved with the standard doses of LPVr are sufficient to maintain virological control during monotherapy and that measurement of LPV concentrations is not useful for predicting virological outcome. Tight control of viral replication in the previous months and strict adherence throughout the mtLPVr regimen could improve the virological efficacy of this maintenance regimen.

Deficient reporting and interpretation of non-inferiority randomized clinical trials in HIV patients: a systematic review

OBJECTIVES

Non-inferiority (NI) randomized clinical trials (RCTs) commonly evaluate efficacy of new antiretroviral (ARV) drugs in human immunodeficiency virus (HIV) patients. Their reporting and interpretation have not been systematically evaluated. We evaluated the reporting of NI RCTs in HIV patients according to the CONSORT statement and assessed the degree of misinterpretation of RCTs when NI was inconclusive or not established.

DESIGN

Systematic review.

METHODS

PubMed, Web of Science, and Scopus were reviewed until December 2011. Selection and extraction was performed independently by three reviewers.

RESULTS

Of the 42 RCTs (n = 21,919; range 41-3,316) selected, 23 were in ARV-naïve and 19 in ARV-experienced patients. Twenty-seven (64%) RCTs provided information about prior RCTs of the active comparator, and 37 (88%) used 2-sided CIs. Two thirds of trials used a NI margin between 10 and 12%, although only 12 explained the method to determine it. Blinding was used in 9 studies only. The main conclusion was based on both intention-to-treat (ITT) and per protocol (PP) analyses in 5 trials, on PP analysis only in 4 studies, and on ITT only in 31 studies. Eleven of 16 studies with NI inconclusive or not established highlighted NI or equivalence, and distracted readers with positive secondary results.

CONCLUSIONS

There is poor reporting and interpretation of NI RCTs performed in HIV patients. Maximizing the reporting of the method of NI margin determination, use of blinding and both ITT and PP analyses, and interpreting negative NI according to actual primary findings will improve the understanding of results and their translation into clinical practice.

Long-term lopinavir/ritonavir monotherapy in HIV-infected children

BACKGROUND

Long-term data are limited on lopinavir/ritonavir monotherapy (mLPV/r) as a treatment simplification strategy in virologically suppressed children.

METHODS

Children with confirmed plasma HIV viral load (VL) <50 copies/mL while receiving double protease inhibitors (dPI) were switched to mLPV/r therapy. Virologic failure (VF) was defined as 2 consecutive VL ≥ 500 or 3 consecutive VL ≥ 50 copies/mL. dPI was resumed within 4 weeks in children with VF. Primary endpoint was the proportion of children with VL < 50 copies/mL while still receiving mLPV/r at week 144.

RESULTS

Forty children were enrolled; 90% were receiving LPV/r + saquinavir and 10% LPV/r + indinavir before simplifying to mLPV/r. Median age was 11.7 years; 50% were female. Median CD4% was 27%. Four (10%) had VL > 50 copies/mL at entry. At week 144, the proportion of children still receiving mLPV/r who had VL < 50 copies/mL was 22 of 40 (55%). The proportion of all children with VL < 50 copies/mL at week 144 was 33 of 40 (82.5%). Among 16 children who had VF and resumed dPI, 11 (69%) achieved VL < 50 copies/mL at week 144. No children with VF had major LPV/r mutations. Having detectable VL at entry and adherence by pill count <95% for >3 times at any visits during the study period significantly predicted VF on mLPV/r (both P = 0.025). The proportion of children with elevated total cholesterol (>200 mg/dL) decreased from 65% at baseline to 40% at week 144 (P = 0.007).

CONCLUSIONS

About half of children maintained virologic suppression on mLPV/r for almost 3 years. VF was common but the majority achieved suppression after resuming dPI and none had major LPV/r mutations. mLPV/r should only be considered for simplified maintenance therapy if frequent VL monitoring to detect VF is available.

Short communication: lamivudine plus a boosted-protease inhibitor as simplification strategy in HIV-infected patients: proof of concept

There are scarce data about the use of a dual therapy with lamivudine plus a ritonavir-boosted protease inhibitor (PI/r) as simplification strategy. We performed a retrospective cohort study of 44 HIV-infected patients on suppressive triple therapy PI/r-based HAART, HBV negative, who discontinued one nucleoside analogue (NA) due to toxicity, and continued dual therapy with lamivudine plus the PI/r. The median time of HIV infection was 18.6 years, and CD4(+) count nadir was 150 cells/μl (6-470). They had received a mean of four regimens before (2-20), and 55% had a previous AIDS diagnosis. In eight cases, a previous resistance test showed two to seven secondary mutations in the protease gene, without resistance to the PI/r. The 184V mutation was not observed, but previous failure with a lamivudine-including regimen had been observed in four patients (9%). At baseline, patients had viral suppression (<50 copies/ml) for a median time of 794 days (235-2344), while receiving atazanavir/r in five cases, lopinavir/r in 14, and darunavir/r in 25. They discontinued mainly tenofovir (19, 43%) and didanosine (15, 34%). During 101.5 patient-years of follow-up, only two patients failed (5%), because of incomplete adherence. CD4(+) count increase at 48 weeks was 55 cells/μl. No new adverse events were observed, although total cholesterol and triglycerides increased significantly during the first 6 months after simplification. In conclusion, dual therapy with lamivudine plus a boosted PI was safe and effective as simplification strategy in patients with toxicity to NA. This combination could be an alternative to mono or triple therapy in hard-to-treat patients.