Higher CNS Penetration Effectiveness Research Articles

Association of combination antiretroviral therapy with risk of neurological diseases in patients with HIV/AIDS in Taiwan: a nested case-control study.

Heterogeneous neurocognitive impairment remains an important issue, even in the era of combination antiretroviral therapy (cART), with an incidence ranging from 15% to 65%. Although ART drugs with higher penetration scores to the central nervous system (CNS) show better HIV replication control in the CNS, the association between CNS penetration effectiveness (CPE) scores and neurocognitive impairment remains inconclusive. To explore whether ART exposure is associated with the risk of neurological diseases among patients with HIV/AIDS, this study in Taiwan involved 2,571 patients with neurological diseases and 10,284 matched, randomly selected patients without neurological diseases between 2010 and 2017. A conditional logistic regression model was used in this study. The parameters for ART exposure included ART usage, timing of exposure, cumulative defined daily dose (DDD), adherence, and cumulative CPE score. Incident cases of neurological diseases, including CNS infections, cognitive disorders, vasculopathy, and peripheral neuropathy, were obtained from the National Health Insurance Research Database in Taiwan. Odds ratios (ORs) for the risk of neurological diseases were conducted using a multivariate conditional logistic regression model. Patients with a history of past exposure (OR: 1.68, 95% confidence interval [CI]:1.22-2.32), low cumulative DDDs (< 2,500) (OR: 1.28, 95% CI: 1.15-1.42), low adherence (0 < adherence (ADH) ≤ 0.8) (OR: 1.46, 95% CI: 1.30-1.64), or high cumulative CPE scores (>14) (OR: 1.34, 95% CI: 1.14-1.57) had a high risk of neurological diseases. When stratified by classes of ART drugs, patients with low cumulative DDDs or low adherence had a high risk of neurological diseases, including NRTIs, PIs, NNRTIs, INSTIs, and multi-drug tablets. Subgroup analyses also suggested that patients with low cumulative DDDs or low adherence had a high risk of neurological diseases when they had high cumulative CPE scores. Patients with high cumulative DDDs or medication adherence were protected against neurological diseases only when they had low cumulative CPE scores (≤ 14). Patients may be at risk for neurological diseases when they have low cumulative DDDs, low adherence, or usage with high cumulative CPE scores. Continuous usage and low cumulative CPE scores of ART drugs may benefit neurocognitive health in patients with HIV/AIDS.

The effect of antiretroviral therapy with high central nervous system penetration on HIV-related cognitive impairment: a systematic review and meta-analysis

ABSTRACT Chronic complications are a significant concern for people living with HIV/AIDS (PLWHA) infection. HIV-associated neurocognitive disorders (HAND) are prevalent in PLWHA. Yet, the efficacy of medications that penetrate the central nervous system (CNS) at preventing or slowing the progression of HAND remains largely unknown. The objective of this study was to determine whether high CNS penetration effectiveness (CPE) regimens improve neurocognitive test scores in PLWHA on combined antiretroviral therapy (cART). Primary literature evaluating cognitive outcomes based on CPE score of cART regimens in PLWHA was assembled from PubMed/Medline and EMBASE. Both randomized controlled trials and observational studies with at least 12 weeks of follow-up were included. A meta-analysis was conducted to calculate the standardized mean difference. Eight trials including a total of 3,303 patients with 13,103 person-years of follow-up were included in the systematic review. Four trials (n = 366 patients) met our inclusion criteria and were included in the meta-analysis. In the meta-analysis, HIV regimens with a high CPE score did not affect NPZ-4 or GDS scores (standardized mean difference (SMD) 0.10, 95% CI −0.19, 0.38; I2 = 26%). Future studies with larger sample sizes are warranted to prospectively evaluate the relationship between CPE and progression of HAND.

Central nervous system-penetrating antiretrovirals impair energetic reserve in striatal nerve terminals.

The use of antiretroviral (ARV) drugs with central nervous system (CNS) penetration effectiveness (CPE) may be useful in the treatment of HIV-associated neurocognitive disorder (HAND) as well as targeting a CNS reservoir in strategies to achieve a functional cure for HIV. However, increased cognitive deficits are linked to at least one of these drugs (efavirenz). As mitochondrial dysfunction has been found with a number of ARVs, and as such can affect neuronal function, the objective of this study was to assess the effects of ARV with high CPE for toxicological profiles on presynaptic nerve terminal energy metabolism. This subcellular region is especially vulnerable in that a constant supply of ATP is required for the proper maintenance of neurotransmitter release and uptake supporting proper neuronal function. We evaluated the effects of acute treatment with ten different high CPE ARVs from five different drug classes on rat cortical and striatal nerve terminal bioenergetic function. While cortical nerve terminal bioenergetics were not altered, striatal nerve terminals exposed to efavirenz, nevirapine, abacavir, emtricitabine, zidovudine, darunavir, lopinavir, raltegravir, or maraviroc (but not indinavir) exhibit reduced mitochondrial spare respiratory capacity (SRC). Further examination of efavirenz and maraviroc revealed a concentration-dependent impairment of striatal nerve terminal maximal mitochondrial respiration and SRC as well as a reduction of intraterminal ATP levels. Depletion of ATP at the synapse may underlie its dysfunction and contribute to neuronal dysfunction in treated HIV infection.

Better Antiretroviral Central Nervous System Penetration is Not Associated with Reduced Chronic Pain in People Living with Human Immunodeficiency Virus.

To determine if better antiretroviral (ARV) central nervous system (CNS) penetration is associated with reduced rates of chronic pain in people living with HIV (PLWH). Chronic pain remains prevalent in PLWH despite widespread ARV use. Mechanisms underlying this prevalence remain unknown, though neuroinflammation from persistent CNS HIV infection and maladaptive plastic changes in the CNS have been implicated. Here we hypothesize that better CNS ARV penetration, measured using the CNS Penetration-Effectiveness (CPE) score, would decrease rates of chronic pain. We interviewed 254 consecutive adults from an HIV clinic in Chiang Mai, Thailand. We collected data on demographics, HIV history, ARV use, and pain characteristics. Patients were evaluated for depression using a Thai two question Patient Health Questionnaire (PHQ-2). Modified CPE score was calculated using established methods and grouped a priori into "low CPE" (≤7, poor penetration) and "high CPE" (≥8, good penetration). CPE score was compared with chronic pain scores in SPSS using appropriate statistical tests. A relationship between CPE score and a positive depression screen was tested further using multivariable binary logistic models. 245 of 254 subjects were on ARVs. Complete ARV data was available for 235 patients. 137 of these 235 patients (58.3%) had a CPE score ≤7, and 98 (41.7%) had a score ≥8. 49 patients had chronic pain, and 9 had neuropathic pain. Low CPE score was not associated with chronic pain (p=0.64), neuropathic pain (p=0.56), or frequent pain (p=0.80), nor was it associated with the severity of reported "worst pain" or "average pain" in the last 24 hours (p=0.18 and 0.48, respectively). Post-hoc analysis revealed that higher CPE score was a significant independent risk factor for depression measured by a positive PHQ-2 screen [OR (95% CI) = 1.29 (1.04-1.61), p=0.02]. This relationship was mediated primarily by exposure to zidovudine. CPE score is not associated with chronic pain in PLWH. Post-hoc analysis demonstrated that CPE score, and zidovudine exposure in particular, predicts a positive depression screen. Given the substantial morbidity associated with chronic pain and mood disorders in PLWH, additional studies to determine preventable and treatable factors are imperative.

The Effect of Central Nervous System Penetration Effectiveness of Highly Active Antiretroviral Therapy on Neuropsychological Performance and Neuroimaging in HIV Infected Individuals.

The incidence of HIV-associated dementia has been greatly reduced in the era of highly active antiretroviral therapy (HAART); however milder forms of cognitive impairment persist. It remains uncertain whether HAART regimens with a high degree of central nervous system penetration effectiveness (CPE) exert beneficial neurological outcomes in HIV-infected (HIV+) individuals on stable treatment. Sixty-four HIV-infected adults on HAART were assigned a CPE score using a published ranking system and divided into high (≥7; n = 35) and low (<7; n = 29) CPE groups. All participants completed neuropsychological testing in addition to structural neuroimaging. Neuropsychological tests included measures known to be sensitive to HIV with values converted into standardized scores (NPZ-4) based on published normative scores. A semi-automated methodology was utilized to assess brain volumetrics within cortical (grey and white matter) and subcortical (thalamus, caudate, putamen) regions of interest. Analyses assessed NPZ-4 and brain volumetric differences between HIV+ individuals with high and low CPE scores. No significant differences in brain integrity were observed between the two groups. Long-term HAART regimens with a high degree of CPE were not associated with significantly improved neuropsychological or neuroimaging outcomes in HIV+ adults. Results suggest that alternate mechanisms may potentially contribute to better neurological outcomes in the era of HAART.

An investigation of the effects of antiretroviral central nervous system penetration effectiveness on procedural learning in HIV+ drug users

Treatment with combination antiretroviral therapy (cART) regimens with a high capacity to penetrate the blood–brain barrier has been associated with lower levels of human immunodeficiency virus (HIV) in the central nervous system (CNS). This study examined neurocognitive performance among a sample of 118 HIV+ substance-dependent individuals (SDIs) and 310 HIV– SDIs. HIV+ participants were prescribed cART regimens with varying capacity to penetrate the CNS as indexed by the revised CNS Penetration Effectiveness (CPE) scale. Participants completed the Rotary Pursuit Task (RPT) and the Weather Prediction Task (WPT)—two measures of procedural learning (PL) with known sensitivity to HIV infection—and a control task of sustained attention. HIV+ SDIs prescribed cART with relatively high CNS penetrance performed significantly more poorly on both tasks than HIV– controls. Task performance of HIV+ SDIs prescribed cART with relatively low CNS penetrance did not differ significantly from either HIV– controls or the HIV+/high CPE group, although a trend toward lower RPT performance than that of HIV– participants was observed. Between-group differences were not seen on a control task of motor impulsivity (Immediate Memory Task), indicating that the observed deficits among HIV+/high CPE SDIs may have some specificity.

Response to Calcagno Comment on “Higher CNS Penetration-Effectiveness of Long-term Combination Antiretroviral Therapy Is Associated With Better HIV-1 Viral Suppression in Cerebrospinal Fluid”

Response to Calcagno Comment on “Higher CNS Penetration-Effectiveness of Long-term Combination Antiretroviral Therapy Is Associated With Better HIV-1 Viral Suppression in Cerebrospinal Fluid”

Comment on “Higher CNS Penetration-Effectiveness of Long-Term Combination Antiretroviral Therapy is Associated With Better HIV-1 Viral Suppression in Cerebrospinal Fluid”

Objectives: To determine HIV-1 RNA in cerebrospinal fluid (CSF) of successfully treated patients and to evaluate if combination antiretroviral treatments with higher central nervous system penetration-effectiveness (CPE) achieve better CSF viral suppression. Methods: Viral loads (VLs) and drug concentrations of lopinavir, atazanavir, and efavirenz were measured in plasma and CSF. The CPE was calculated using 2 different methods. Results: The authors analyzed 87 CSF samples of 60 patients. In 4 CSF samples, HIV-1 RNA was detectable with 43-82 copies per milliliter. Median CPE in patients with detectable CSF VL was significantly lower compared with individuals with undetectable VL: CPE of 1.0 (range, 1.0-1.5) versus 2.3 (range, 1.0-3.5) using the method of 2008 (P = 0.011) and CPE of 6 (range, 6-8) versus 8 (range, 5-12) using the method of 2010 (P = 0.022). The extrapolated CSF trough levels for atazanavir (n = 12) were clearly above the 50% inhibitory concentration (IC50) in only 25% of samples; both patients on atazanavir/ritonavir with detectable CSF HIV-1 RNA had trough levels in the range of the presumed IC50. The extrapolated CSF trough level for lopinavir (n = 42) and efavirenz (n = 18) were above the IC50 in 98% and 78%, respectively, of samples, including the patients with detectable CSF HIV-1 RNA. Conclusions: This study suggests that treatment regimens with high intracerebral efficacy reflected by a high CPE score are essential to achieve CSF HIV-1 RNA suppression. The CPE score including all drug components was a better predictor for treatment failure in the CSF than the sole concentrations of protease inhibitor or non-nucleoside reverse transcriptase inhibitor in plasma or CSF.

Higher CNS Penetration-Effectiveness of Long-term Combination Antiretroviral Therapy Is Associated With Better HIV-1 Viral Suppression in Cerebrospinal Fluid

To determine HIV-1 RNA in cerebrospinal fluid (CSF) of successfully treated patients and to evaluate if combination antiretroviral treatments with higher central nervous system penetration-effectiveness (CPE) achieve better CSF viral suppression. Viral loads (VLs) and drug concentrations of lopinavir, atazanavir, and efavirenz were measured in plasma and CSF. The CPE was calculated using 2 different methods. The authors analyzed 87 CSF samples of 60 patients. In 4 CSF samples, HIV-1 RNA was detectable with 43-82 copies per milliliter. Median CPE in patients with detectable CSF VL was significantly lower compared with individuals with undetectable VL: CPE of 1.0 (range, 1.0-1.5) versus 2.3 (range, 1.0-3.5) using the method of 2008 (P = 0.011) and CPE of 6 (range, 6-8) versus 8 (range, 5-12) using the method of 2010 (P = 0.022). The extrapolated CSF trough levels for atazanavir (n = 12) were clearly above the 50% inhibitory concentration (IC50) in only 25% of samples; both patients on atazanavir/ritonavir with detectable CSF HIV-1 RNA had trough levels in the range of the presumed IC50. The extrapolated CSF trough level for lopinavir (n = 42) and efavirenz (n = 18) were above the IC50 in 98% and 78%, respectively, of samples, including the patients with detectable CSF HIV-1 RNA. This study suggests that treatment regimens with high intracerebral efficacy reflected by a high CPE score are essential to achieve CSF HIV-1 RNA suppression. The CPE score including all drug components was a better predictor for treatment failure in the CSF than the sole concentrations of protease inhibitor or nonnucleoside reverse transcriptase inhibitor in plasma or CSF.

Cognitive function after several years of antiretroviral therapy with stable central nervous system penetration score

Previous studies in HIV-infected populations have yielded conflicting results on the effect of antiretroviral therapy (ART) on cognition. Our objective was to investigate the effect of several years of ART with stable central nervous system penetration effectiveness (CPE) score on neuropsychological performance in HIV-infected individuals. We analysed a clinical cohort of HIV-infected patients who initiated ART between June 2003 and December 2006 and maintained stable CPE scores. Patients were evaluated with a short neuropsychological battery. Using linear regression, we examined the relationship between results of cognitive tests and CPE scores in all patients. Patients were divided into three similarly sized groups (CPE ≤ 1, CPE between 1.5 and 2.5, and CPE ≥ 2.5). We found that ART with high CPE scores was associated with poorer executive performances in HIV-1-infected patients. These results suggest that cognitive performance in treated HIV-infected patients could be influenced by ART.

Does use of antiretroviral therapy regimens with high central nervous system penetration improve survival in HIV-infected adults?

The aim of the study was to determine whether combination antiretroviral therapy (cART) with high central nervous system penetration-effectiveness (CPE) rank (neurocART) is associated with increased survival benefit compared with non-neurocART. Prospective data were examined for HIV-positive patients in the Asia Pacific HIV Observational Database who had commenced cART. CPE rank was calculated using the 2010 rankings process. NeurocART status was assigned to regimens with a CPE rank of 8 or more. Survival was analysed using Cox proportional hazards models with covariates updated at changes in cART regimen and with deaths up to 90 days after regimen cessation attributed to that regimen. Sensitivity analyses were conducted to examine the robustness of analysis assumptions. Among 5882 patients, 308 deaths occurred. The hazard ratio (HR) for neurocART use was 0.89 (P=0.35) when data were stratified by cohort and adjusted for age, mode of HIV exposure, hepatitis B virus coinfection, AIDS-defining illness, CD4 count (cells/μL) and regimen count. Sensitivity analyses showed similar nonsignificant results. We also examined a composite endpoint of AIDS-defining illness or death (HR=0.93; P=0.61), baseline regimen as neurocART (HR=0.95; P=0.69), CPE category (P=0.71) and prior neurocART duration (P=0.16). No association between CD4 cell count and neurocART use was observed (P=0.52). Our findings do not show a significant overall survival benefit associated with neurocART compared with cART. The potential benefit associated with neurocART in terms of prevention of neurocognitive impairment did not translate into an improvement in overall survival in this population. These findings were limited by the low incidence of associated mortality. Further studies and more extensive data are needed to address these limitations.

Antiretroviral therapy CNS penetration and HIV-1–associated CNS disease

The impact of different antiretroviral agents on the risk of developing or surviving CNS disease remains unknown. The aim of this study was to investigate whether using antiretroviral regimens with higher CNS penetration effectiveness (CPE) scores was associated with reduced incidence of CNS disease and improved survival in the UK Collaborative HIV Cohort (CHIC) Study. Adults without previous CNS disease, who commenced combination antiretroviral therapy (cART) between 1996 and 2008, were included (n = 22,356). Initial and most recent cART CPE scores were calculated. CNS diseases were HIV encephalopathy (HIVe), progressive multifocal leukoencephalopathy (PML), cerebral toxoplasmosis (TOXO), and cryptococcal meningitis (CRYPTO). Incidence rates and overall survival were stratified by CPE score. A multivariable Poisson regression model was used to identify independent associations. The median (interquartile range) CPE score for initial cART regimen increased from 7 (5-8) in 1996-1997 to 9 (8-10) in 2000-2001 and subsequently declined to 6 (7-8) in 2006-2008. Differences in gender, HIV acquisition risk group, and ethnicity existed between CPE score strata. A total of 251 subjects were diagnosed with a CNS disease (HIVe 80; TOXO 59; CRYPTO 56; PML 54). CNS diseases occurred more frequently in subjects prescribed regimens with CPE scores ≤ 4, and less frequently in those with scores ≥ 10; however, these differences were nonsignificant. Initial and most recent cART CPE scores ≤ 4 were independently associated with increased risk of death. Clinical status at time of commencing cART influences antiretroviral selection and CPE score. This information should be considered when utilizing CPE scores for retrospective analyses.

Effects of central nervous system antiretroviral penetration on cognitive functioning in the ALLRT cohort.

Differences in antiretroviral distribution into the central nervous system (CNS) may impact neurocognitive status. We assessed the relationship between estimates of antiretroviral therapy penetration into the CNS, using a published ranking system, and neurocognitive status in HIV-positive participants with plasma HIV-1 RNA (vRNA) suppression. Participants with at least 6 weeks ongoing antiretroviral drug use and vRNA less than 50 copies/ml (N = 2636; 83% male, median baseline CD4 T cells: 244 cells/μl) had at least one neuroscreen assessment [Trail Making Test, Part A and B; Wechsler Adult Intelligence Scale-Revised (WAIS-R) Digit Symbol] at 10 413 neurovisits. Neuroscreen test scores were demographically adjusted and converted to Z-scores (NPZ3: lower scores imply more impairment). Central nervous system penetration effectiveness (CPE) ranks of 0.0 (low), 0.5 (medium), or 1.0 (high) were assigned to antiretrovirals and summed per regimen, per neurovisit. Multivariate linear regression models using generalized estimating equations assessed NPZ3 scores with respect to antiretroviral regimen. Covariates were retained if P ≤ 0.1. A final model demonstrated that better NPZ3 scores were associated with higher CPE among participants taking more than three antiretroviral drugs (+0.07 per one unit increase in CPE score; P = 0.004) but not among participants with three or less antiretroviral drugs in the regimen (+0.01; P = 0.5). Results were adjusted for demographics, injection drug use, hepatitis C virus serostatus, CD4 cell count (current and nadir), baseline vRNA, antiretroviral experience, and years since first antiretroviral drug use. Use of antiretroviral drugs with better estimated CNS penetration may be associated with better neurocognitive functioning; some people may require more than three antiretroviral drugs to treat HIV in the CNS. Clinically this means antiretroviral regimens could be designed to optimize estimated CNS penetration without sacrificing virologic and immunologic benefits.