The HIV antiretroviral drug efavirenz has LSD-like properties

Oral Administration of Efavirenz Dysregulates the Tph2 Gene in Brain Serotonergic Areas and Alters Weight and Mood in Mice

Most HIV-antiretroviral drugs have adverse effects. Efavirenz (EFV) is an example of a drug with neuropsychiatric effects, such as anxiety, depression, and suicidal thoughts, in people living with HIV (PLWH). The mechanisms by which EFV causes neuropsychiatric alterations in PLWH are complex, multifactorial, and not fully understood, although several studies in animals have reported changes in brain energy metabolism, alterations in monoamine turnover, GABA, and glutamate levels, and changes in 5-HT receptors. In this report, we studied the effects of EFV on the serotonergic system in healthy mice, specifically, whether EFV results in alterations in the levels of the tryptophan hydroxylase 2 (Tph2) gene in the brain. EFV (10 mg/kg) and distilled water (1.5 µL/kg) (control group) were orally administered to the mice for 36 days. At the end of the treatment, Tph2 expression levels in mouse brains were measured, and mood was evaluated by three trials: the forced swim test, elevated plus maze, and open field test. Our results revealed dysregulation of Tph2 expression in the brainstem, amygdala, and hypothalamus in the EFV group, and 5-HT levels increased in the amygdala in the EFV group. In the behavioral tests, mice given EFV exhibited a passive avoidance response in the forced swim test and anxiety-like behavior in the elevated plus maze, and they lost weight. Herein, for the first time, we showed that EFV triggered dysregulation of the Tph2 gene in the three serotonergic areas studied; and 5-HT levels increased in the amygdala using the ELISA method. However, further studies will be necessary to clarify the increase of 5-HT in the amygdala as well as understand the paradoxical decrease in body weight with the simultaneous increase in food consumption. It will also be necessary to measure 5-HT by other techniques different from ELISA, such as HPLC.

The Impact of Drugs and Substance Abuse on Viral Pathogenesis-A South African Perspective

Illicit drug and alcohol abuse have significant negative consequences for individuals who inject drugs/use drugs (PWID/UDs), including decreased immune system function and increased viral pathogenesis. PWID/UDs are at high risk of contracting or transmitting viral illnesses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). In South Africa, a dangerous drug-taking method known as "Bluetoothing" has emerged among nyaope users, whereby the users of this drug, after injecting, withdraw blood from their veins and then reinject it into another user. Hence, the transmission of blood-borne viruses (BBVs) is exacerbated by this "Bluetooth" practice among nyaope users. Moreover, several substances of abuse promote HIV, HBV, and HCV replication. With a specific focus on the nyaope drug, viral replication, and transmission, we address the important influence of abused addictive substances and polysubstance use in this review.

A Systematic Review of Risk Factors and Consequences of Nyaope Usage: The Illicit Street Drug Containing HIV Antiretrovirals

South Africa currently has the highest number of cases of HIV in the world. HIV antiretrovirals (ARVs) are publicly available across the country to address this crisis. However, a consequence of widely available ARVs has been the diversion of these drugs for recreational usage in a drug cocktail commonly known as "nyaope" or "whoonga," which poses a significant public health concern. To better understand nyaope, we conducted a systematic review investigating the risks and consequences associated with its usage. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searches were conducted in eight different databases and screened thereafter. Articles were eligible for inclusion if they included analysis of least one nyaope user and considered either demographics, risk factors, or consequences of usage. Data extracted included study characteristics and limitations, as well as demographic factors, risk factors for usage in the general population, and consequences. Quality assessments were performed using the Joanna Briggs Institute's tools. Searches produced a total of 228 articles and, after screening, a total of 19 articles were eligible for inclusion. There was a pooled total of 807 nyaope users, all in South Africa. Major risk factors for usage were being male, unemployed, not completing secondary education, pressure from peer groups, having HIV, prior use of cannabis, and to a lesser extent, usage of other substances such as alcohol and tobacco. While young adults tend to be at high-risk, evidence indicates that adolescents are also at-risk. Consequences of usage include high rates of infection, cortical atrophy, depression, and addiction. Addiction was shown to lead to individuals stealing from friends and family to pay for the drugs. HIV-positive nyaope users were more likely to partake in risk behaviours and tended to have high viral loads. Nyaope's rise has been linked to many health and social issues. Considering that this may also disrupt HIV control efforts in South Africa, there is an urgent need to address the rise of nyaope.

Efavirenz: History, Development and Future

Efavirenz (Sustiva^®) is a first-generation non-nucleoside reverse transcriptase inhibitor (NNRTI) used to treat human immunodeficiency virus (HIV) type 1 infection or to prevent the spread of HIV. In 1998, the FDA authorized efavirenz for the treatment of HIV-1 infection. Patients formerly required three 200 mg efavirenz capsules daily, which was rapidly updated to a 600 mg tablet that only required one tablet per day. However, when given 600 mg once daily, plasma efavirenz concentrations were linked not only to poor HIV suppression but also to toxicity. Clinical data suggested that the standard dose of efavirenz could be reduced without compromising its effectiveness, resulting in a reduction in side effects and making the drug more affordable. Therefore, ENCORE1 was performed to compare the efficiency and safeness of a reduced dose of efavirenz (400 mg) with the standard dose (600 mg) plus two NRTI in antiretroviral-naïve HIV-infected individuals. Nowadays, due to the emergence of integrase strand transfer inhibitors (INSTIs), some consider that it is time to stop using efavirenz as a first-line treatment on a global scale, in the parts of the world where that is possible. Efavirenz has been a primary first-line antiviral drug for more than 15 years. However, at this moment, the best use for efavirenz could be for pre-exposure prophylaxis (PrEP) and repurposing in medicine.

Prolonged efavirenz exposure reduces peripheral oxytocin and vasopressin comparable to known drugs of addiction in male Sprague Dawley rats

Introduction

Several drugs of abuse (DOA) are capable of modulating neurohypophysial hormones, such as oxytocin (OT) and vasopressin (VP), potentially resulting in the development of psychological abnormalities, such as cognitive dysfunction, psychoses, and affective disorders. Efavirenz (EFV), widely used in Africa and globally to treat HIV, induces diverse neuropsychiatric side effects while its abuse has become a global concern. The actions of EFV may involve neurohypophysial system (NS) disruption like that of known DOA. This study investigated whether sub-chronic EFV exposure, at a previously-determined rewarding dose, alters peripheral OT and VP levels versus that of a control, ∆⁹-tetrahydrocannabinol (∆⁹-THC), methamphetamine (MA) and cocaine.

Materials and methods

To simulate the conditions under which reward-driven behavior had previously been established for EFV, male Sprague Dawley rats (n = 16/exposure) received intraperitoneal vehicle (control) or drug administration across an alternating sixteen-day dosing protocol. Control administration (saline/olive oil; 0.2 ml) occurred on odd-numbered and drug administration (EFV: 5 mg/kg, ∆⁹-THC: 0.75 mg/kg, MA: 1 mg/kg, or cocaine: 20 mg/kg) on even-numbered days followed by euthanasia, trunk blood collection and plasma extraction for neuropeptide assay. Effect of drug exposure on peripheral OT and VP levels was assessed versus controls and quantified using specific ELISA kits. Statistical significance was determined by Kruskal-Wallis ANOVA, with p < 0.05. Ethics approval: NWU-00291-17-A5.

Results

Delta-9-THC reduced OT and VP plasma levels (p < 0.0001, p = 0.0141; respectively), cocaine reduced plasma OT (p = 0.0023), while MA reduced plasma VP levels (p = 0.0001), all versus control. EFV reduced OT and VP plasma levels (p < 0.0001; OT and VP) versus control, and similar to ∆⁹-THC.

Conclusion

EFV markedly affects the NS in significantly reducing both plasma OT and VP equivalent to DOA. Importantly, EFV has distinct effects on peripheral OT and VP levels when assessed within the context of drug dependence. The data highlights a possible new mechanism underlying previously documented EFV-induced effects in rats, and whereby EFV may induce neuropsychiatric adverse effects clinically; also providing a deeper understanding of the suggested abuse-potential of EFV.

Molecular targets of psychedelic-induced plasticity

Psychedelic research across different disciplines and biological levels is growing at a remarkably fast pace. In the prospect of a psychedelic drug becoming again an approved treatment, much of these efforts have been oriented toward exploring the relationship between the actual psychedelic effects and those manifestations of therapeutic interest. Considering the central role of the serotonin 5-HT_2A receptor in the distinct effects of psychedelics in human psyche, neuropharmacology sits at the center of this debate and exploratory continuum. Here we discuss some of the most recent findings in human studies and contextualize them considering previous preclinical models studying phenomena related to synaptic plasticity. A special emphasis is placed on knowledge gaps, challenges, and limitations to evaluate the underpinnings of psychedelics' potential antidepressant action.

HIV-Associated Apathy/Depression and Neurocognitive Impairments Reflect Persistent Dopamine Deficits

Individuals living with human immunodeficiency virus type 1 (HIV-1) are often plagued by debilitating neurocognitive impairments and affective alterations;the pathophysiology underlying these deficits likely includes dopaminergic system dysfunction. The present review utilized four interrelated aims to critically examine the evidence for dopaminergic alterations following HIV-1 viral protein exposure. First, basal dopamine (DA) values are dependent upon both brain region andexperimental approach (i.e., high-performance liquid chromatography, microdialysis or fast-scan cyclic voltammetry). Second, neurochemical measurements overwhelmingly support decreased DA concentrations following chronic HIV-1 viral protein exposure. Neurocognitive impairments, including alterations in pre-attentive processes and attention, as well as apathetic behaviors, provide an additional line of evidence for dopaminergic deficits in HIV-1. Third, to date, there is no compelling evidence that combination antiretroviral therapy (cART), the primary treatment regimen for HIV-1 seropositive individuals, has any direct pharmacological action on the dopaminergic system. Fourth, the infection of microglia by HIV-1 viral proteins may mechanistically underlie the dopamine deficit observed following chronic HIV-1 viral protein exposure. An inclusive and critical evaluation of the literature, therefore, supports the fundamental conclusion that long-term HIV-1 viral protein exposure leads to a decreased dopaminergic state, which continues to persist despite the advent of cART. Thus, effective treatment of HIV-1-associated apathy/depression and neurocognitive impairments must focus on strategies for rectifying decreases in dopamine function.

Novel Phenethylamines and Their Potential Interactions With Prescription Drugs: A Systematic Critical Review

BACKGROUND

The novel phenethylamines 4-fluoroamphetamine (4-FA) and 2,5-dimethoxy-4-bromophenethylamine (2C-B) fall in the top 10 most used new psychoactive substances (NPSs) among high-risk substance users. Various phenethylamines and NPS are also highly used in populations with mental disorders, depression, or attention deficit hyperactivity disorder (ADHD). Moreover, NPS use is highly prevalent among men and women with risky sexual behavior. Considering these specific populations and their frequent concurrent use of drugs, such as antidepressants, ADHD medication, and antiretrovirals, reports on potential interactions between these drugs, and phenethylamines 4-FA and 2C-B, were reviewed.

METHODS

The authors performed a systematic literature review on 4-FA and 2C-B interactions with antidepressants (citalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, duloxetine, bupropion, venlafaxine, phenelzine, moclobemide, and tranylcypromine), ADHD medications (atomoxetine, dexamphetamine, methylphenidate, and modafinil), and antiretrovirals.

RESULTS

Limited literature exists on the pharmacokinetics and drug-drug interactions of 2C-B and 4-FA. Only one case report indicated a possible interaction between 4-FA and ADHD medication. Although pharmacokinetic interactions between 4-FA and prescription drugs remain speculative, their pharmacodynamic points toward interactions between 4-FA and ADHD medication and antidepressants. The pharmacokinetic and pharmacodynamic profile of 2C-B also points toward such interactions, between 2C-B and prescription drugs such as antidepressants and ADHD medication.

CONCLUSIONS

A drug-drug (phenethylamine-prescription drug) interaction potential is anticipated, mainly involving monoamine oxidases for 2C-B and 4-FA, with monoamine transporters being more specific to 4-FA.

Psychedelic-like Properties of Quipazine and Its Structural Analogues in Mice

Known classic psychedelic serotonin 2A receptor (5-HT2AR) agonists retain a tryptamine or phenethylamine at their structural core. However, activation of the 5-HT2AR can be elicited by drugs lacking these fundamental scaffolds. Such is the case of the N-substituted piperazine quipazine. Here, we show that quipazine bound to and activated 5-HT2AR as measured by [3H]ketanserin binding displacement, Ca2+ mobilization, and accumulation of the canonical Gq/11 signaling pathway mediator inositol monophosphate (IP1) in vitro and in vivo. Additionally, quipazine induced via 5-HT2AR an expression pattern of immediate early genes (IEG) in the mouse somatosensory cortex consistent with that of classic psychedelics. In the mouse head-twitch response (HTR) model of psychedelic-like action, quipazine produced a lasting effect with high maximal responses during the peak effect that were successfully blocked by the 5-HT2AR antagonist M100907 and absent in 5-HT2AR knockout (KO) mice. The acute effect of quipazine on HTR appeared to be unaffected by serotonin depletion and was independent from 5-HT3R activation. Interestingly, some of these features were shared by its deaza bioisostere 2-NP, but not by other closely related piperazine congeners, suggesting that quipazine might represent a distinct cluster within the family of psychoactive piperazines. Together, our results add to the mounting evidence that quipazine's profile matches that of classic psychedelic 5-HT2AR agonists at cellular signaling and behavioral pharmacology levels.

Uptake of antiretroviral treatment and viral suppression among men who have sex with men and transgender women in sub-Saharan Africa in an observational cohort study: HPTN 075

Objectives:

HPTN 075 enrolled men who have sex with men (MSM) and transgender women (TGW) in sub-Saharan Africa. Persons in HIV care or on antiretroviral treatment (ART) were not eligible to enroll. We evaluated antiretroviral (ARV) drug use, viral suppression, and drug resistance in this cohort over a 12-month follow-up period.

Methods:

Assessments included 64 participants with HIV (39 MSM, 24 TGW, and one gender not specified). ARV drugs were detected using a qualitative assay. Viral load (VL) and drug resistance testing were performed using commercial assays.

Results:

Over 12 months, the proportion of participants using ARV drugs increased from 28.1% to 59.4% and the proportion with VLs <400 copies/mL increased from 21.9% to 57.8%. The rate of ART failure (detection of drugs without viral suppression) was similar at screening and 12 months (12.0% and 11.1%, respectively) and was similar among MSM and TGW. Two participants developed HIV drug resistance during follow-up.

Conclusions:

Over 12 months, ARV drug use in the cohort more than doubled and viral suppression increased nearly threefold without a significant increase in ART failure or drug resistance. These results suggest that ART can be successfully scaled up for HIV prevention and treatment in this high-risk population.

HIV Neuropathogenesis in the Presence of a Disrupted Dopamine System

Antiretroviral therapy (ART) has transformed HIV into a chronic condition, lengthening and improving the lives of individuals living with this virus. Despite successful suppression of HIV replication, people living with HIV (PLWH) are susceptible to a growing number of comorbidities, including neuroHIV that results from infection of the central nervous system (CNS). Alterations in the dopaminergic system have long been associated with HIV infection of the CNS. Studies indicate that changes in dopamine concentrations not only alter neurotransmission, but also significantly impact the function of immune cells, contributing to neuroinflammation and neuronal dysfunction. Monocytes/macrophages, which are a major target for HIV in the CNS, are responsive to dopamine. Therefore, defining more precisely the mechanisms by which dopamine acts on these cells, and the changes in cellular function elicited by this neurotransmitter are necessary to develop therapeutic strategies to treat neuroHIV. This is especially important for vulnerable populations of PLWH with chemically altered dopamine concentrations, such as individuals with substance use disorder (SUD), or aging individuals using dopamine-altering medications. The specific neuropathologic and neurocognitive consequences of increased CNS dopamine remain unclear. This is due to the complex nature of HIV neuropathogenesis, and logistical and technical challenges that contribute to inconsistencies among cohort studies, animal models and in vitro studies, as well as lack of demographic data and access to human CNS samples and cells. This review summarizes current understanding of the impact of dopamine on HIV neuropathogenesis, and proposes new experimental approaches to examine the role of dopamine in CNS HIV infection. Graphical abstract HIV Neuropathogenesis in the Presence of a Disrupted Dopamine System. Both substance abuse disorders and the use of dopaminergic medications for age-related diseases are associated with changes in CNS dopamine concentrations and dopaminergic neurotransmission. These changes can lead to aberrant immune function, particularly in myeloid cells, which contributes to the neuroinflammation, neuropathology and dysfunctional neurotransmission observed in dopamine-rich regions in HIV+ individuals. These changes, which are seen despite the use antiretroviral therapy (ART), in turn lead to further dysregulation of the dopamine system. Thus, in individuals with elevated dopamine, the bi-directional interaction between aberrant dopaminergic neurotransmission and HIV infection creates a feedback loop contributing to HIV associated neurocognitive dysfunction and neuroHIV. However, the distinct contributions and interactions made by HIV infection, inflammatory mediators, ART, drugs of abuse, and age-related therapeutics are poorly understood. Defining more precisely the mechanisms by which these factors influence the development of neurological disease is critical to addressing the continued presence of neuroHIV in vulnerable populations, such as HIV-infected older adults or drug abusers. Due to the complexity of this system, understanding these effects will require a combination of novel experimental modalities in the context of ART. These will include more rigorous epidemiological studies, relevant animal models, and in vitro cellular and molecular mechanistic analysis.

Therapeutic activities of naringenin on efavirenz-induced sleep-like disorder in the midbrain of white albino mice

OBJECTIVES

Efavirenz, has proven to be effective in suppressing human immunodeficiency virus (HIV) viral load; however, complaints of sleep disorders including hallucination, and insomnia have greatly contributed to non-adherence to antiretroviral therapy. This study aimed at investigating therapeutic activities of naringenin on efavirenz-induced sleep disorder.

MATERIALS AND METHODS

Sixty mice were divided into six groups of control, combination antiretroviral therapy (cART), efavirenz, naringenin, naringenin/efavirenz and naringenin/cART. Efavirenz, cART, and naringenin were administered orally and daily at 15 mg/kg, 24 mg/kg and 50 mg/kg, respectively for 28 days. Post neurobehavioral test, oxidative stress, histology and immunohistochemistry for dopamine were carried out after administration process.

RESULTS

Efavirenz (P<0.0001) and cART (P<0.01) significantly increased immobility during open field (P<0.01), escape time in seconds (sec) in Morris water maze (P<0.001) and numbers of head-twitch response (HTR) (P<0.0001). Similarly, there was a significant increase in malondialdehyde (MDA) (P<0.0001) and decreased superoxide dismutase (SOD) (P<0.001) and reduced glutathione (GSH) (P<0.001); however, naringenin-treated groups potentiated anti-oxidant function by reducing oxidative stress (P<0.01). Histological evaluation demonstrated severe neurodegeneration, vacuolization and pyknosis in efavirenz and cART compared to naringenin groups. Dopaminergic neurons using immunohistochemial antibody (tyrosine hydroxylase) staining showed poor immunoreactivity in efavirenz and cART in contrast to naringenin groups.

CONCLUSION

Efavirenz and cART have the potential of inducing sleep disorder possibly due to their capability to trigger inflammation and deplete dopamine level. However, naringenin has proven to be effective in ameliorating these damages.

CYP46A1-dependent and independent effects of efavirenz treatment

Cholesterol excess in the brain is mainly disposed via cholesterol 24-hydroxylation catalysed by cytochrome P450 46A1, a CNS-specific enzyme. Cytochrome P450 46A1 is emerging as a promising therapeutic target for various brain diseases with both enzyme activation and inhibition having therapeutic potential. The rate of cholesterol 24-hydroxylation determines the rate of brain cholesterol turnover and the rate of sterol flux through the plasma membranes. The latter was shown to affect membrane properties and thereby membrane proteins and membrane-dependent processes. Previously we found that treatment of 5XFAD mice, an Alzheimer's disease model, with a small dose of anti-HIV drug efavirenz allosterically activated cytochrome P450 46A1 in the brain and mitigated several disease manifestations. Herein, we generated Cyp46a1-/- 5XFAD mice and treated them, along with 5XFAD animals, with efavirenz to ascertain cytochrome P450 46A1-dependent and independent drug effects. Efavirenz-treated versus control Cyp46a1-/- 5XFAD and 5XFAD mice were compared for the brain sterol and steroid hormone content, amyloid β burden, protein and mRNA expression as well as synaptic ultrastructure. We found that the cytochrome P450 46A1-dependent efavirenz effects included changes in the levels of brain sterols, steroid hormones, and such proteins as glial fibrillary acidic protein, Iba1, Munc13-1, post-synaptic density-95, gephyrin, synaptophysin and synapsin-1. Changes in the expression of genes involved in neuroprotection, neurogenesis, synaptic function, inflammation, oxidative stress and apoptosis were also cytochrome P450 46A1-dependent. The total amyloid β load was the same in all groups of animals, except lack of cytochrome P450 46A1 decreased the production of the amyloid β40 species independent of treatment. In contrast, altered transcription of genes from cholinergic, monoaminergic, and peptidergic neurotransmission, steroid sulfation and production as well as vitamin D3 activation was the main CYP46A1-independent efavirenz effect. Collectively, the data obtained reveal that CYP46A1 controls cholesterol availability for the production of steroid hormones in the brain and the levels of biologically active neurosteroids. In addition, cytochrome P450 46A1 activity also seems to affect the levels of post-synaptic density-95, the main postsynaptic density protein, possibly by altering the calcium/calmodulin-dependent protein kinase II inhibitor 1 expression and activity of glycogen synthase kinase 3β. Even at a small dose, efavirenz likely acts as a transcriptional regulator, yet this regulation may not necessarily lead to functional effects. This study further confirmed that cytochrome P450 46A1 is a key enzyme for cholesterol homeostasis in the brain and that the therapeutic efavirenz effects on 5XFAD mice are likely realized via cytochrome P450 46A1 activation.

Neuropsychiatric Effects of Antiviral Drugs

The adverse events of antiviral drugs are dose-dependent and often reversible. The nervous system is often affected and to date, many studies have been published regarding the central nervous system toxicity of antiviral agents. They may cause significant neuropsychiatric complications, which range from mild symptoms such as irritability and difficulty sleeping to severe complications such as depression, psychosis, and painful peripheral neuropathy, side effects which may necessitate discontinuation of treatment. The pathogenetic mechanisms may involve molecular targets common to other centrally active drugs, including human monoamine oxidase‐A (MAO‐A), serotonin receptors, gamma-aminobutyric acid (GABA) GABA-A receptors, 5-HT2A and 5-HT2C receptors and others. Notable examples include oseltamivir which may act as MAO inhibitor and efavirenz, which has an affinity for serotonin 5-HT2 and GABA-A receptors, the serotonin transporter, the MAO enzyme, and the vesicular monoamine transporter, with subjective effects which may be similar to those of the psychedelic hallucinogen lysergic acid diethylamide (LSD). Other antiviral drugs with prominent nervous system effects include nucleoside reverse transcriptase inhibitors, which are associated with the development of peripheral neuropathy after prolonged use (an effect strongly associated with older drugs which have since fallen into disfavor such as stavudine) and interferons, which may cause depression. Clinicians should be familiar with such adverse effects in order to recognise them promptly once they occur and manage them appropriately.

Perinatal exposure of rats to the HIV drug efavirenz affects medial prefrontal cortex cytoarchitecture

Efavirenz (EFV) is used for antiretroviral treatment of HIV infection, and successfully inhibits viral replication and mother-to-child transmission of HIV during pregnancy and childbirth. Unfortunately, the drug induces neuropsychiatric symptoms such as anxiety and depressed mood and potentially affects cognitive performance. EFV acts on, among others, the serotonin transporter and serotonin receptors that are expressed in the developing brain. Yet, how perinatal EFV exposure affects brain cytoarchitecture remains unclear. Here, we exposed pregnant and lactating rats to EFV, and examined in the medial prefrontal cortex (mPFC) of their adult offspring the effects of the maternal EFV exposure on cortical architecture. We observed a significant decrease in the number of cells, mainly mature neurons, in the infra/prelimbic and cingulate cortices of adult offspring. Next, we found an altered cortical cytoarchitecture characterized by a significant reduction in deep- and superficial-layer cells. This was accompanied by a sharp increase in programmed cell death, as we identified a significantly higher number of cleaved Caspase-3-positive cells. Finally, the serotonergic and dopaminergic innervation of the mPFC subdomains was increased. Thus, the perinatal exposure to EFV provoked in the mPFC of adult offspring cell death, significant changes in cytoarchitecture, and disturbances in serotonergic and dopaminergic innervation. Our results are important in the light of EFV treatment of HIV-positive pregnant women, and its effect on brain development and cognitive behavior.

Risk and protective factors for whoonga use among adolescents in South Africa

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Adolescents are reporting recreational exposure and use of ARVs in South Africa.

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Individual level risk factors increase risk for whoonga use or known use among adolescents.

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Food insecurity has a slightly protective effect on whoonga use or known use among adolescents.

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Surveillance studies are warranted to understand multilevel risk factors of whoonga.

Background

Antiretroviral therapy (ART) is publicly available in South Africa in response to the urgent need to address HIV and AIDS. Off-label use of ARV medication alone or in combination with other substances is known as “whoonga” and “nyaope” in South Africa. Diversion of ARVs for whoonga use is not well understood, especially among adolescents. This secondary analysis explores risk and protective factors for adolescent whoonga use in a community-based HIV endemic setting.

Methods

Data on whoonga use were derived from a baseline survey of N = 200 adolescents recruited for participation in a randomized controlled trail to reduce adolescent HIV risk behaviors and depression. Risk and protective factors for adolescent whoonga use were explored using an ecological systems framework using one-way ANOVAs, chi-squared tests and hierarchical regression.

Results

Individual level factors increased the odds of whoonga use or known use such as child age OR:1.22 (95% CI, 1.03–1.43), hazardous drug use OR:1.62 (95% CI, 1.02–2.59), and hazardous alcohol OR:1.80 (95% CI, 1.05–3.09). Food insecurity appears to have a slightly protective effect on the odds of whoonga use or reports of use among people adolescents knew OR:0.649 (95% CI, 0.541–0.779).

Conclusions

Larger epidemiological studies should expand the surveillance of hazardous alcohol use and illicit drug use, specifically for recreational use of prescription medication. Granular data is warranted to characterize the patters of use, especially among highly vulnerable populations. Future surveillance studies that explore these multi-level relationships are warranted to further understand this phenomenon among teens in South Africa.

Bidirectional Associations among Nicotine and Tobacco Smoke, NeuroHIV, and Antiretroviral Therapy

People living with HIV (PLWH) in the antiretroviral therapy (ART) era may lose more life-years to tobacco use than to HIV. Yet, smoking rates are more than twice as high among PLWH than the general population, contributing not just to mortality but to other adverse health outcomes, including neurocognitive deficits (neuroHIV). There is growing evidence that synergy with chronic inflammation and immune dysregulation that persists despite ART may be one mechanism by which tobacco smoking contributes to neuroHIV. This review will summarize the differential effects of nicotine vs tobacco smoking on inflammation in addition to the effects of tobacco smoke components on HIV disease progression. We will also discuss biomarkers of inflammation via neuroimaging as well as biomarkers of nicotine dependence (e.g., nicotine metabolite ratio). Tobacco smoking and nicotine may impact ART drug metabolism and conversely, certain ARTs may impact nicotine metabolism. Thus, we will review these bidirectional relationships and how they may contribute to neuroHIV and other adverse outcomes. We will also discuss the effects of tobacco use on the interaction between peripheral organs (lungs, heart, kidney) and subsequent CNS function in the context of HIV. Lastly, given the dramatic rise in the use of electronic nicotine delivery systems, we will discuss the implications of vaping on these processes. Despite the growing recognition of the importance of addressing tobacco use among PLWH, more research is necessary at both the preclinical and clinical level to disentangle the potentially synergistic effects of tobacco use, nicotine, HIV, cognition and immune dysregulation, as well as identify optimal approaches to reduce tobacco use. Graphical Abstract Proposed model of the relationships among HIV, ART, smoking, inflammation, and neurocognition. Solid lines represent relationships supported by evidence. Dashed lines represent relationships for which there is not enough evidence to make a conclusion. (a) HIV infection produces elevated levels of inflammation even among virally suppressed individuals. (b) HIV is associated with deficits in cognition function. (c) Smoking rates are higher among PLWH, compared to the general population. (d) The nicotine metabolite ratio (NMR) is associated with smoking behavior. (e) HIV and tobacco use are both associated with higher rates of psychiatric comorbidities, such as depression, and elevated levels of chronic stress. These factors may represent other mechanisms linking HIV and tobacco use. (f) The relationship between nicotine, tobacco smoking, and inflammation is complex, but it is well-established that smoking induces inflammation; the evidence for nicotine as anti-inflammatory is supported in some studies, but not others. (g) The relationship between tobacco use and neurocognition may differ for the effects of nicotine (acute nicotine use may have beneficial effects) vs. tobacco smoking (chronic use may impair cognition). (h) Elevated levels of inflammation may be associated with deficits in cognition. (i) PLWH may metabolize nicotine faster than those without HIV; the mechanism is not yet known and the finding needs validation in larger samples. We also hypothesize that if HIV-infection increases nicotine metabolism, then we should observe an attenuation effect once ART is initiated. (j) It is possible that the increase in NMR is due to ART effects on CYP2A6. (k) We hypothesize that faster nicotine metabolism may result in higher levels of inflammation since nicotine has anti-inflammatory properties.

High Dietary Fat Modulates Neurobehavioural Effect of Lopinavir/ Ritonavir in Mice

BACKGROUND

Lopinavir/Ritonavir (LR) is a protease inhibitor used human immunodeficiency virus infection management. There have been issues regarding the effects of fat on LR efficacy and the possibility of neurological deficits following prolonged use, there is however a dearth of research examining this.

AIMS

The effects of LR administered with normal or High-Fat Diet (HFD) on neurobehaviour, neurochemistry and oxidative stress in healthy mice were examined.

METHODS

Mice were randomly-assigned into eight groups of ten (n=10) animals each. The groups were normal control [Standard Diet, (SD)], HFD control, 3 groups of LR incorporated into SD (100/25, 200/50 and 400/100 mg/kg of feed), and 3 groups of LR with HFD (100/25, 200/50 and 400/100 mg/kg of feed). Mice were fed daily for six weeks, following which open field, elevated-plus maze (EPM), radial-arm maze and Y-maze behaviours were scored. Twenty-four hours after tests, mice were euthanised and brains were homogenised for estimation of oxidative stress, L-glutamate level and acetylcholinesterase activity.

RESULTS

LR was associated with a reduction in HFD-induced weight gain, suppression of open-field behaviours with SD, and counteraction of HFD-induced changes in working-memory, open-field and anxiety-related behaviours. Also, LR causes increased lipid peroxidation and superoxide dismutase activity; and a decrease in brain glutamate, irrespective of dietary composition. Increased fat catabolism leading to increased oxidative stress could possibly account for the weight changes, while a decrease in brain glutamate could account for the changes in open-field behaviours in mice fed SD.

CONCLUSION

LR alters neurobehaviour, oxidative stress and brain glutamate in mice; however, only its effects on neurobehaviour are affected by diet.

Evaluating Neurodevelopmental Consequences of Perinatal Exposure to Antiretroviral Drugs: Current Challenges and New Approaches

As antiretroviral therapy (ART) becomes increasingly affordable and accessible to women of childbearing age across the globe, the number of children who are exposed to Human Immunodeficiency Viruses (HIV) but remain uninfected is on the rise, almost all of whom were also exposed to ART perinatally. Although ART has successfully aided in the decline of mother-to-child-transmission of HIV, the long-term effects of in utero exposure to ART on fetal and postnatal neurodevelopment remain unclear. Evaluating the safety and efficacy of therapeutic drugs for pregnant women is a challenge due to the historic limitations on their inclusion in clinical trials and the dynamic physiological states during pregnancy that can alter the pharmacokinetics of drug metabolism and fetal drug exposure. Thus, much of our data on the potential consequences of ART drugs on the developing nervous system comes from preclinical animal models and clinical observational studies. In this review, we will discuss the current state of knowledge and existing approaches to investigate whether ART affects fetal brain development, and describe novel human stem cell-based strategies that may provide additional information to better predict the impact of specific drugs on the human central nervous system. Graphical Abstract Approaches to evaluate the impact of drugs on the developing brain. Dysregulation of the developing nervous system can lead to long-lasting changes. Integration of data from animal models, clinical observations, and cell culture studies is needed to predict the safety of therapeutic antiretroviral drugs during pregnancy. New approaches include human induced pluripotent stem cell (iPSC)-based 2D and 3D models of neuronal networks and brain regions, as well as single cell profiling in response to drug exposure.

Dopaminergic impact of cART and anti-depressants on HIV neuropathogenesis in older adults

The success of combination antiretroviral therapy (cART) has transformed HIV infection into a chronic condition, resulting in an increase in the number of older, cART-treated adults living with HIV. This has increased the incidence of age-related, non-AIDS comorbidities in this population. One of the most common comorbidities is depression, which is also associated with cognitive impairment and a number of neuropathologies. In older people living with HIV, treating these overlapping disorders is complex, often creating pill burden or adverse drug-drug interactions that can exacerbate these neurologic disorders. Depression, NeuroHIV and many of the neuropsychiatric therapeutics used to treat them impact the dopaminergic system, suggesting that dopaminergic dysfunction may be a common factor in the development of these disorders. Further, changes in dopamine can influence the development of inflammation and the regulation of immune function, which are also implicated in the progression of NeuroHIV and depression. Little is known about the optimal clinical management of drug-drug interactions between cART drugs and antidepressants, particularly in regard to dopamine in older people living with HIV. This review will discuss those interactions, first examining the etiology of NeuroHIV and depression in older adults, then discussing the interrelated effects of dopamine and inflammation on these disorders, and finally reviewing the activity and interactions of cART drugs and antidepressants on each of these factors. Developing better strategies to manage these comorbidities is critical to the health of the aging, HIV-infected population, as the older population may be particularly vulnerable to drug-drug interactions affecting dopamine.

Neuropsychiatric and Neurocognitive Manifestations in HIV-Infected Children Treated With Efavirenz in South Africa-A Retrospective Case Series

Background: Efavirenz is associated with transient neuropsychiatric manifestations but the impact on neurocognition in children is unknown. Genetically slow metabolizers of efavirenz may be at risk of toxicity. This study describes neuropsychiatric and neurocognitive manifestations of South African children with suspected efavirenz neurotoxicity. Method: This retrospective study describes clinical features of 12 children with features consistent with efavirenz neurotoxicity between 2008 and 2014. Results: Twelve children (4 males, 8 females) aged 3-12 years (median 8.4 years) were referred to a dedicated pediatric neuroHIV service. Eight were of indigenous African (black) ancestry and 4 were of mixed ancestry. The total duration on efavirenz-containing ART at the time of referral was 6-72 (mean 31) months. Two children (both of black ancestry) were phenotypically slow metabolizers and presented with acute manifestations and high plasma efavirenz concentrations above normal range resulting in discontinuation of efavirenz. Ten other children had clinical presentations compatible with efavirenz neurotoxicity but had normal or sub-therapeutic plasma efavirenz concentrations and continued treatment with efavirenz. The acute neuropsychiatric manifestations reported included drowsiness, seizures, sleep disturbances, personality changes, ataxia, and slurred speech. These were noticed 2-8 weeks (mean 5 weeks) after commencing efavirenz and resolved over a few weeks. Nine children had neurocognitive deficits and showed poor performance in all neurocognitive domains that were tested. Interpretation: Efavirenz causes transient neuropsychiatric adverse effects and may contribute to poor long-term neurocognitive outcomes in HIV-infected children. Prospective studies comparing efavirenz-treated and efavirenz-naïve children are needed to further elucidate the manifestations of efavirenz toxicity.

Chemical profiling of the street cocktail drug 'nyaope' in South Africa using GC-MS II: Stability studies of the cannabinoid, opiate and antiretroviral components during sample storage

Nyaope is a mixture of low grade heroin, cannabis products, antiretroviral drugs and other materials added as bulking agents. It is a highly physically additive mixture which is smoked by users. As part of the development of a method for the analysis and profiling of nyaope this study evaluates the stability of the cannabinoid, opiate and antiretroviral components of nyaope during storage following seizure. Conditions used were those typically used for storage of drug seizures: in a desiccator in a refrigerator, in a desiccator in the dark at room temperature, in a desiccator in daylight at room temperature and ambient room temperature in the dark in a cabinet used for storage of drug seizures. Street samples of cannabis (Δ⁹-tetrahydrocannabinol) and heroin were mixed with efavirenz and nevirapine tablets to mimic a nyaope sample. The samples were homogenized and transferred into glass bottles and extracted with tertiary butyl alcohol (tBuOH) and analysed by gas chromatography - mass spectrometry (GC-MS) after the powdered drugs had been stored for intervals of 0 and 24 h under each storage condition. The data obtained indicates that the target drug components in nyaope samples decompose and that for comparison purposes the drug extracts should be prepared in tBuOH immediately after seizure because of the decomposition of the drug components during storage prior to extraction and analysis. The implications of this work are that law enforcement agencies dealing with nyaope and wanting to compare drug samples may need to change their practice around how the drug is handled after seizure but prior to analysis.

Recreational ART use among individuals living with HIV/AIDS in South Africa: Examining longitudinal ART initiation and viral suppression

BACKGROUND

South Africa has the highest number of people living with HIV (PLWH) and one of the largest antiretroviral therapy (ART) programs globally. High rates of substance use comorbidity exist, including speculation of recreational ART use (i.e., mixing ART with other illicit drugs). Recreational ART use may affect viral load among PLWH due to ART nonadherence and/or viral resistance; however, prior quantitative research has not examined rates of recreational ART use, nor associations with HIV treatment outcomes longitudinally.

METHODS

Data were drawn from a prospective, observational cohort study (n = 500) of ART-eligible adults recruited from two HIV voluntary counseling and testing centers in Cape Town, and Johannesburg, South Africa. Multiple logistic regression models assessed recreational ART use as a predictor of ART initiation over six months and viral load suppression over nine months, above and beyond other substance use (binge drinking and illicit drug use).

RESULTS

Approximately 5% (n = 24) reported recreational ART use, which was less frequent in Cape Town compared to Johannesburg (AOR = 0.025; 95%CI: 0.003-0.19; p < 0.001). Recreational ART use was not significantly associated with ART initiation or viral suppression. Other substance use, but not recreational ART use, was significantly associated with lower odds of ART initiation (AOR = 0.54; 95%CI: 0.33-0.87; p = .01) and viral suppression (AOR = 0.47; 95%CI: 0.25-0.89; p = .02).

CONCLUSIONS

Recreational ART use was infrequent and not uniquely associated with ART initiation or viral suppression. Findings suggest that comorbid use of other substances is ultimately what may make recreational ART use problematic for ongoing engagement in care and viral suppression.

Neurodevelopmental and behavioral consequences of perinatal exposure to the HIV drug efavirenz in a rodent model

Efavirenz is recommended as a preferred first-line drug for women of childbearing potential living with human immunodeficiency virus. Efavirenz is known for its central nervous system side effects, which are partly mediated by serotonergic actions. The neurotransmitter serotonin exerts neurotrophic effects during neurodevelopment and antenatal exposure to serotonergic agents has been linked to developmental delay. Although the teratogenic risks of efavirenz appear to be minimal, data on long-term developmental effects remain scarce. Here, we aimed to investigate the short- and long-term behavioral and neurodevelopmental effects of perinatal efavirenz exposure. We treated pregnant rats from gestation day 1 until postnatal day 7 with efavirenz (100 mg/kg) or vehicle. We measured behavioral outcomes in male offspring during the first 3 postnatal weeks, adolescence and adulthood, and conducted brain immunohistochemistry analyses after sacrifice. Perinatal efavirenz exposure resulted in reduced body weight and delayed reflex and motor development. During adulthood, we observed a decrease in the total number of cells and mature neurons in the motor cortex, as well as an increase in the number of Caspase-3-positive cells and serotonergic fibers. Together, our data show a developmental delay and persistent changes in the brain motor cortex of rats exposed to efavirenz perinatally. Because over 1 million children born annually are exposed to antiretroviral therapy, our findings underline the need for clinical studies on long-term neurodevelopmental outcomes of perinatal exposure to efavirenz.

Drug repurposing for Dravet syndrome in scn1Lab-/- mutant zebrafish

Dravet syndrome (DS) is a severe genetic epileptic encephalopathy with onset during the first year of life. Zebrafish models recapitulating human diseases are often used as drug discovery platforms, but also for drug repurposing testing. It was recently shown that pharmacological modulation of three serotonergic (5-HT) receptors (5-HT_1D , 5-HT_2C , 5-HT_2A ) exerts antiseizure effects in a zebrafish scn1Lab^-/- mutant model of DS. Using the zebrafish DS model, our aim was to examine the possibility of repurposing efavirenz (EFA), lisuride (LIS), and rizatriptan (RIZA), marketed medicines with a 5-HT on- or off-target profile, as antiepileptic drugs for DS. To examine whether these compounds have a broader antiseizure profile, they were tested in pentylenetetrazol and ethyl ketopentenoate (EKP) zebrafish models. Pharmacological effects were assessed by locomotor behavior, local field potential brain recordings, and bioluminescence. EFA was active in all models, whereas LIS was selectively active in the zebrafish DS model. Mainly, a poor response was observed to RIZA. Taken together, our preclinical results show that LIS could be a potential candidate for DS treatment. EFA was also active in the EKP model, characterized by a high level of treatment resistance, and hence these data are potentially important for future treatment of drug-resistant epilepsy.

Inflammatory Mechanisms and Cascades Contributing to Neurocognitive Impairment in HIV/AIDS

Neurocognitive impairment caused by chronic human immunodeficiency virus (HIV) infection is a growing concern. In this chapter we discuss the inflammatory mechanisms underlying the pathology of asymptomatic and mild neurocognitive impairment in the context of antiretroviral therapy. We discuss the role of HIV, viral proteins, and virally infected cells on the development of neuroinflammation and the effect of viral proteins on the cells of the central nervous system.We examine how these collective factors result in an inflammatory context that triggers the development of neurocognitive impairment in HIV. We assess the contribution of antiretrovirals and drugs of abuse, including methamphetamine, cannabis, and opioids, to the neurotoxic and neuroinflammatory milieu that leads to the development of neurocognitive impairment in HIV-infected individuals. We also examined circulating biomarkers, NF-L, sCD163, and sCD14, pertinent to identifying changes in the CNS that could indicate real-time changes in patient physiology. Lastly, we discuss future studies, such as exosomes and the microbiome, which could play a role in the HIV-induced neuroinflammation that eventually manifests as cognitive impairment.

Antiretroviral Drug Use and HIV Drug Resistance Among Young Women in Rural South Africa: HPTN 068

BACKGROUND

Antiretroviral (ARV) drugs are used for HIV treatment and prevention. We analyzed ARV drug use and HIV drug resistance in a cohort of young women in rural South Africa enrolled in the HIV Prevention Trials Network (HPTN) 068 study, which evaluated the use of a cash transfer conditional on school attendance to reduce HIV incidence.

METHODS

ARV drug testing was performed using plasma samples from 2526 young women. This included 2526 enrollment samples (80 HIV-infected and 2446 HIV-uninfected) and 162 seroconversion samples (first HIV-positive study visit). Testing was performed using a qualitative assay that detects 20 ARV drugs from 5 drug classes. HIV drug resistance testing was performed with the ViroSeq HIV-1 Genotyping System for samples that had HIV viral loads ≥400 copies per milliliter.

RESULTS

At enrollment, ARV drugs were detected in 10 (12.5%) of 80 HIV-infected young women. None of 2446 HIV-uninfected young women had ARV drugs detected at enrollment. ARV drugs were also detected in 16 (9.9%) of 162 seroconverters. At enrollment, 9 (13.4%) of 67 young women with genotyping results had HIV drug resistance; resistance was also detected in 9 (6.9%) of 131 seroconverters with genotyping results.

CONCLUSIONS

Most of the HIV-infected young women in this cohort from rural South Africa were not taking ARV drugs, suggesting they were unaware of their HIV status or were not in care. HIV drug resistance was detected in young women with both prevalent and new HIV infection.

Efavirenz exposure, alone and in combination with known drugs of abuse, engenders addictive-like bio-behavioural changes in rats

Efavirenz is abused in a cannabis-containing mixture known as Nyaope. The addictive-like effects of efavirenz (5, 10 and 20 mg/kg) was explored using conditioned place preference (CPP) in rats following sub-acute exposure vs. methamphetamine (MA; 1 mg/kg) and Δ⁹-tetrahydrocannabinol (THC; 0.75 mg/kg). The most addictive dose of efavirenz was then compared to THC alone and THC plus efavirenz following sub-chronic exposure using multiple behavioural measures, viz. CPP, sucrose preference test (SPT) and locomotor activity. Peripheral superoxide dismutase (SOD), regional brain lipid peroxidation and monoamines were also determined. Sub-acute efavirenz (5 mg/kg) had a significant rewarding effect in the CPP comparable to MA and THC. Sub-chronic efavirenz (5 mg/kg) and THC + efavirenz were equally rewarding using CPP, with increased cortico-striatal dopamine (DA), and increased lipid peroxidation and SOD. Sub-chronic THC did not produce CPP but significantly increased SOD and decreased hippocampal DA. Sub-chronic THC + efavirenz was hedonic in the SPT and superior to THC alone regarding cortico-striatal lipid peroxidation and sucrose preference. THC + efavirenz increased cortico-striatal DA and decreased serotonin (5-HT). Concluding, efavirenz has dose-dependent rewarding effects, increases oxidative stress and alters regional brain monoamines. Efavirenz is hedonic when combined with THC, highlighting its abuse potential when combined with THC.

Depression and Suicidal Ideation Among HIV-Infected Adults Receiving Efavirenz Versus Nevirapine in Uganda: A Prospective Cohort Study

BACKGROUND

Evidence regarding potential adverse neuropsychiatric effects of efavirenz is conflicting, and data from sub-Saharan Africa, where 70% of persons living with HIV (PLHIV) reside and efavirenz is used as first-line therapy, are limited.

OBJECTIVE

To estimate associations between efavirenz use and depression and suicidal ideation among PLHIV in Uganda.

DESIGN

Prospective observational cohort study. (ClinicalTrials.gov: NCT01596322).

SETTING

Mbarara, Uganda.

PARTICIPANTS

Adult PLHIV enrolled at the start of antiretroviral therapy (ART) and observed every 3 to 4 months from 2005 to 2015.

MEASUREMENTS

The exposure of interest was time-varying efavirenz use, defined as use during the 7 days and in 60 or more of the 90 days before a study visit, compared with nevirapine use. Self-reported outcomes were depression, defined as a mean score greater than 1.75 on the Hopkins Symptom Checklist depression subscale, and suicidal ideation. Multivariable-adjusted generalized estimating equations (GEE) logistic regression, Cox proportional hazards regression, and marginal structural models were fit to estimate the association between efavirenz use and the risk for depression and suicidal ideation.

RESULTS

694 participants (median age, 33 years; median pretreatment CD4+ count, 1.8 × 109 cells/L) contributed 1200 person-years of observation (460 person-years receiving efavirenz). No baseline differences in depression or suicidal ideation were found between patients ever exposed to efavirenz and those never exposed to efavirenz and receiving nevirapine (P > 0.80 for both). Of 305 participants ever-exposed to efavirenz, 61 (20.0%) and 19 (6.2%) had depression and suicidal ideation, respectively, on at least 1 follow-up visit, compared with 125 (32.1%) and 47 (12.1%) of the 389 who received nevirapine. In adjusted GEE models, efavirenz use was associated with decreased odds of depression compared with nevirapine use (adjusted odds ratio, 0.62 [95% CI, 0.40 to 0.96]) and was not significantly associated with suicidal ideation (adjusted odds ratio, 0.61 [CI, 0.30 to 1.25]). Time-to-event and marginal structural models yielded similar estimates.

LIMITATION

Nonrandom assignment to treatment and substantial differences between the efavirenz and nevirapine groups.

CONCLUSION

No evidence was found that use of efavirenz in first-line ART increased the risk for depression or suicidal ideation compared with nevirapine use among PLHIV in Uganda.

PRIMARY FUNDING SOURCE

National Institutes of Health.

The current limits in virtual screening and property prediction

Beyond finding inhibitors that show high binding affinity to the respective target, there is the challenge of optimizing their properties with respect to metabolic and toxicological issues, as well as further off-target effects. To reduce the experimental effort of synthesizing and testing actual substances in corresponding assays, virtual screening has become an indispensable toolbox in preclinical development. The scope of application covers the prediction of molecular properties including solubility, metabolic liability and binding to antitargets, such as the hERG channel. Furthermore, prediction of binding sites and drugable targets are emerging aspects of virtual screening. Issues involved with the currently applied computational models including machine learning algorithms are outlined, such as limitations to the accuracy of prediction and overfitting.

Antiretroviral drug use and HIV drug resistance among MSM and transgender women in sub-Saharan Africa

OBJECTIVE

To analyze antiretroviral drug use and HIV drug resistance among HIV-infected MSM and transgender women who were screened for participation in the HIV Prevention Trials Network 075 study.

METHODS

A qualitative assay was used to detect 20 antiretroviral drugs in five drug classes; this assay is based on liquid chromatography coupled with high-resolution accurate-mass mass spectrometry. HIV viral load testing was performed using the RealTime HIV-1 Viral Load Assay. HIV drug resistance testing was performed using the ViroSeq HIV-1 Genotyping System. Logistic regression was used to evaluate factors associated with study outcomes.

RESULTS

Antiretroviral drugs were detected in 63 (34.4%) of 183 participants who had confirmed HIV infection at screening; 11 (17.5%) of the 63 participants were not virally suppressed. Six (54.5%) of the 11 participants had drug-resistant HIV, including four who had multiclass resistance. Seven (63.6%) of the 11 were at risk of acquiring resistance to additional antiretroviral drugs. In multivariate model, antiretroviral drugs were more frequently detected in older participants, those recruited from Kisumu, Kenya, and those who reported ever having been in HIV care or on antiretroviral therapy (ART).

CONCLUSION

Most of HIV-infected persons screened for participation in HIV Prevention Trials Network 075 were not on ART, and many of those who were on ART were not virally suppressed. Many of those participants had drug-resistant HIV. These findings highlight the need for improved HIV care for African MSM and transgender women.

HIV Non-Nucleoside Reverse Transcriptase Inhibitor Efavirenz Reduces Neural Stem Cell Proliferation in Vitro and in Vivo

The prevalence of HIV-associated neurocognitive disorders (HAND) remains high despite combination antiretroviral therapy (cART). There is evidence that neural stem cells (NSCs) can migrate to sites of brain injury such as those caused by inflammation and oxidative stress, which are pathological features of HAND. Thus, reductions in NSCs may contribute to HAND pathogenesis. Since the HIV non-nucleoside reverse transcriptase inhibitor efavirenz (EFV) has previously been associated with cognitive deficits and promotion of oxidative stress pathways, we examined its effect on NSCs in vitro as well as in C57BL/6J mice. Here we report that EFV induced a decrease in NSC proliferation in vitro as indicated by MTT assay, as well as BrdU and nestin immunocytochemistry. In addition, EFV decreased intracellular NSC adenosine triphosphate (ATP) stores and NSC mitochondrial membrane potential (MMP). Further, we found that EFV promoted increased lactate dehydrogenase (LDH) release, activation of p38 mitogen-activated protein kinase (MAPK), and increased Bax expression in cultured NSCs. Moreover, EFV reduced the quantity of proliferating NSCs in the subventricular zone (SVZ) of C57BL/6J mice as suggested by BrdU, and increased apoptosis as measured by active caspase-3 immunohistochemistry. If these in vitro and in vivo models translate to the clinical syndrome, then a pharmacological or cell-based therapy aimed at opposing EFV-mediated reductions in NSC proliferation may be beneficial to prevent or treat HAND in patients receiving EFV.

Efavirenz is related to neuropsychiatric symptoms among adults, but not among adolescents living with human immunodeficiency virus in Kilimanjaro, Tanzania

OBJECTIVES

To explore the relationship between Efavirenz (EFV) and neuropsychiatric symptoms among adults and adolescents living with human immunodeficiency virus (HIV) in Kilimanjaro, Tanzania.

METHODS

Cross-sectional study among HIV-infected adults (age 18-65) and adolescents (age 12-17) on antiretroviral treatment attending Kilimanjaro Christian Medical Centre, Moshi, Tanzania. Neuropsychiatric symptoms were measured using the Hospital Anxiety and Depression Scale (HADS), the Symptom Checklist 90 (SCL-90) and the Mini-International Neuropsychiatric Interview (MINI). manova and chi-squared tests were used to test differences between EFV and non-EFV-treated participants.

RESULTS

A total of 215 adults and 150 adolescents participated. About 52% of adults and 37% of adolescents used EFV. Among adults, depression scores were higher for those on EFV (HADS (Cohen's D: 0.38; P = 0.02) and SCL-90 (Cohen's D: 0.24; P = 0.03). Among adolescents, those on EFV had lower scores on depression (HADS (Cohen's D: 0.3; P = 0.02) and SCL-90 (Cohen's D: 0.1; P = 0.02). About 10% of adults reported suicidal thoughts, but there was no difference between those on EFV and those without. Lastly, adults on EFV reported higher levels of problematic alcohol use (P = 0.003).

CONCLUSIONS

In line with the previous studies, EFV is associated with depressive symptoms and problematic alcohol use among HIV-infected adults in Tanzania. In contrast, EFV was associated with lower levels of depressive symptoms in adolescents in Tanzania. Particularly among adults, close monitoring of depressive symptoms and alcohol use is indicated.

Neuropsychiatric Effects of HIV Antiviral Medications

The development of antiretroviral therapy (ART) has dramatically increased the lifespan of HIV patients but treatment is complicated by numerous adverse effects and toxicities. ART complications include neuropsychiatric, metabolic, gastrointestinal, cardiac, and numerous other toxicities, and clinicians often have to choose one toxicity over another to offer the best medication regimen for a patient. Some antiviral drugs cause significant neuropsychiatric complications, including depression, cognitive impairment, and sleep disturbance. Even in careful studies, it may be difficult to determine which effects are related to the virus, the immune system, or the treatment. Of the six currently marketed classes of antiviral drugs, the nucleoside reverse transcriptase inhibitors and the non-nucleoside reverse transcriptase inhibitors have been most commonly associated with neuropsychiatric complications. Within these classes, certain drugs are more likely to cause difficulty than others. We review the contention regarding the central nervous system (CNS) complications of efavirenz, as well as debate about the role of CNS penetration in drug effectiveness and toxicity. A thorough working knowledge of the neuropsychiatric consequences of ART allows clinicians to tailor treatment more successfully to individual patients as well as to identify ART more quickly as the source of a problem or symptom.

Beyond drug-drug interactions: effects of transporter inhibition on endobiotics, nutrients and toxins

INTRODUCTION

Membrane transport proteins play a central role in regulating the disposition of endobiotics, dietary nutrients and environmental toxins. The inhibition of transporters by drugs has potential physiologic consequences. The full extent of the effect of drugs on the function of transporters is poorly understood because only a small subset of the hundreds of transporters expressed in humans - primarily those mediating the rate-determining step in the elimination of specific drugs - are assessed during clinical development. Areas covered: We provide a comprehensive overview of literature reports implicating the inhibition of transporters as the mechanism for off-target effects of drugs. Expert opinion: Transporter inhibition, the mechanism of action of many marketed drugs, appears to play an underappreciated role in a number of side effects including vitamin deficiency, edema, dyslipidemia, cholestasis and gout. Cell systems more broadly expressing transporter networks and methods like unbiased metabolomics should be incorporated into the screening paradigm to expand our understanding of the impact of drugs on the physiologic function of transporters and to allow for these effects to be taken into account in drug discovery and clinical practice.

Efavirenz: What is known about the cellular mechanisms responsible for its adverse effects

The HIV infection remains an important health problem worldwide. However, due to the efficacy of combined antiretroviral therapy (cART), it has ceased to be a mortal condition, becoming a chronic disease instead. Efavirenz, the most prescribed non-nucleoside analogue reverse transcriptase inhibitor (NNRTI), has been a key component of cART since its commercialization in 1998. Though still a drug of choice in many countries, its primacy has been challenged by the arrival of newer antiretroviral agents with better toxicity profiles and treatment adherence. The major side effects related to EFV have been widely described in clinical studies, however the mechanisms that participate in their pathogenesis remain largely ununderstood. This review provides an insight into the cellular and molecular mechanisms responsible for the development of the most significant undesired effects induced by efavirenz, both short- and long-term, revealed by in vitro and in vivo experimental pharmacological research. Growing evidence implicates the drug in energy metabolism, mitochondrial function, and other cellular processes involved in stress responses including oxidative stress, inflammation and autophagy.

Antiretroviral Drug Use in a Cross-Sectional Population Survey in Africa: NIMH Project Accept (HPTN 043)

BACKGROUND

Antiretroviral (ARV) drug treatment benefits the treated individual and can prevent HIV transmission. We assessed ARV drug use in a community-randomized trial that evaluated the impact of behavioral interventions on HIV incidence.

METHODS

Samples were collected in a cross-sectional survey after a 3-year intervention period. ARV drug testing was performed using samples from HIV-infected adults at 4 study sites (Zimbabwe; Tanzania; KwaZulu-Natal and Soweto, South Africa; survey period 2009-2011) using an assay that detects 20 ARV drugs (6 nucleoside/nucleotide reverse transcriptase inhibitors, 3 nonnucleoside reverse transcriptase inhibitors, and 9 protease inhibitors; maraviroc; raltegravir).

RESULTS

ARV drugs were detected in 2011 (27.4%) of 7347 samples; 88.1% had 1 nonnucleoside reverse transcriptase inhibitors ± 1-2 nucleoside/nucleotide reverse transcriptase inhibitors. ARV drug detection was associated with sex (women>men), pregnancy, older age (>24 years), and study site (P < 0.0001 for all 4 variables). ARV drugs were also more frequently detected in adults who were widowed (P = 0.006) or unemployed (P = 0.02). ARV drug use was more frequent in intervention versus control communities early in the survey (P = 0.01), with a significant increase in control (P = 0.004) but not in intervention communities during the survey period. In KwaZulu-Natal, a 1% increase in ARV drug use was associated with a 0.14% absolute decrease in HIV incidence (P = 0.018).

CONCLUSIONS

This study used an objective, biomedical approach to assess ARV drug use on a population level. This analysis identified factors associated with ARV drug use and provided information on ARV drug use over time. ARV drug use was associated with lower HIV incidence at 1 study site.

Pharmacogenetics of efavirenz discontinuation for reported central nervous system symptoms appears to differ by race

BACKGROUND

Efavirenz frequently causes central nervous system (CNS) symptoms. We evaluated genetic associations with efavirenz discontinuation for CNS symptoms within 12 months of treatment initiation.

METHODS

Patients had initiated efavirenz-containing regimens at an HIV primary care clinic in the Southeastern United States and had at least 12 months of follow-up data. Polymorphisms in CYP2B6 and CYP2A6 defined efavirenz metabolizer categories. Genome-wide genotyping enabled adjustment for population stratification.

RESULTS

Among 563 evaluable patients, 99 (17.5%) discontinued efavirenz within 12 months, 29 (5.1%) for CNS symptoms. The hazard ratio (HR) for efavirenz discontinuation for CNS symptoms in slow versus extensive metabolizers was 4.9 [95% confidence interval (CI): 1.9-12.4; P=0.001]. This HR in Whites was 6.5 (95% CI: 2.3-18.8; P=0.001) and 2.6 in Blacks (95% CI: 0.5-14.1; P=0.27). Considering only slow metabolizers, the HR in Whites versus Blacks was 3.1 (95% CI: 0.9-11.0; P=0.081). The positive predictive value of slow metabolizer genotypes for efavirenz discontinuation was 27% in Whites and 11% in Blacks.

CONCLUSION

Slow metabolizer genotypes were associated significantly with efavirenz discontinuation for reported CNS symptoms. This association was considerably stronger in Whites than in Blacks.

The dual modulatory effects of efavirenz on GABAA receptors are mediated via two distinct sites

Efavirenz is a widely prescribed medicine used to treat type 1 human immunodeficiency virus (HIV-1), the most prevalent pathogenic strain of the virus responsible for the acquired immune deficiency syndrome (AIDS) pandemic. Under prescribed dosing conditions, either alone or in combination therapy, efavirenz-induced CNS disturbances are frequently reported. Efavirenz was recently reported to interact in a similar concentration range with a number of receptors, transporters and ion channels including recombinant rat α1β2γ2 GABA_A receptors whose actions were potentiated (Gatch et al., 2013; Dalwadi et al., 2016). Now we report on the molecular mechanism of efavirenz on GABA_A receptors as a function of concentration and subunit composition via whole-cell recordings of GABA-activated currents from HEK293 cells expressing varying subunit configurations of GABA_A receptors. Efavirenz elicited dual effects on the GABA response; it allosterically potentiated currents at low concentrations, whereas it inhibited currents at higher concentrations. The allosteric potentiating action on GABA_A receptors was pronounced in the α1β2γ2, α2β2γ2 and α4β2γ2 configurations, greatly diminished in the α6β2γ2 configuration, and completely absent in the α3β2γ2 or α5β2γ2 configuration. In stark contrast, the inhibitory modulation of efavirenz at higher concentrations was evident in all subunit configurations examined. Moreover, efavirenz-induced modulatory effects were dependent on GABA concentration ([GABA]), with a pronounced impact on currents activated by low [GABA] but little effect at saturating [GABA]. Mutation of a highly-conserved threonine to phenylalanine in transmembrane domain 2 of the α1 subunit abolished the inhibitory effect of efavirenz in α1β2 receptors. Finally, mutations of any of the three conserved extracellular residues in α1/2/4 subunits to the conserved residues at the corresponding positions in α3/5 subunits (i.e., R84P, M89L or I120L) completely eliminated the potentiating effect of efavirenz in α1β2γ2 configuration. These findings demonstrate that efavirenz's positive allosteric modulation of the GABA_A receptor is mediated via a novel allosteric site associated with the extracellular domain of the receptor.

Neuropsychiatric complications of efavirenz in children with HIV infection

Efavirenz is an effective antiretroviral agent widely used as part of first-line regimen in HIV1-infected children and adults. Neuropsychiatric adverse effects are reported in up to 50% of users. These include dizziness, insomnia, abnormal dreams, headache and impaired concentration. The plasma level of efavirenz may be key in the development of these adverse effects. Even among individuals taking recommended doses for weight, the plasma levels vary widely. Genetic polymorphisms leading to different allelic variants of the CYP2B6 enzyme, making some individuals slow metabolizers may play a role. These allelic variants are highest in people of African descent. This report examines the neuropsychiatric adverse effects of efavirenz, and the strength of the data that the product may result in neuronal damage.

Pharmacologic rationale for the NK1R antagonist, aprepitant as adjunctive therapy in HIV

BACKGROUND

Many HIV infected individuals with suppressed viral loads experience chronic immune activation frequently developing neurological impairment designated as HIV associated neurocognitive disorder (HAND). Adjunctive therapies may reduce HIV associated inflammation and therefore decrease the occurrence of HAND.

METHODS

We have conducted in vitro, animal and clinical studies of the neurokinin 1 receptor (NK1R) antagonist aprepitant in HIV/SIV infection.

RESULTS

Aprepitant inhibits HIV infection of human macrophages ex vivo with an ED50 ~ 5 µM. When administered at 125 mg once daily for 12 months to SIV-infected rhesus macaques, aprepitant reduced viral load by approximately tenfold and produced anti-anxiolytic effects. The anti-viral and anti-anxiolytic effects occur at approximately the third month of dosing; and the effects are sustained throughout the duration of drug administration. Protein binding experiments in culture media and animal and human plasma indicate that the free fraction of aprepitant is lower than previously reported supporting usage of higher doses in vivo. The analysis of blood samples from HIV positive individuals treated for 2 weeks with aprepitant at doses up to 375 mg demonstrated reduced levels of pro-inflammatory cytokines including G-CSF, IL-6, IL-8 and TNFα. Decreased pro-inflammatory cytokines may reduce HIV comorbidities associated with chronic inflammation.

CONCLUSIONS

Our results provide evidence for a unique combination of antiretroviral, anti-inflammatory and behavioral modulation properties of aprepitant in vitro and in vivo. These results provide robust support for a clinical exposure target above that recommended for chemotherapy-induced nausea and vomiting. Doses up to 375 mg once daily in HIV-infected patients still elicit sub-therapeutic exposure of aprepitant though effective plasma concentrations can be achievable by proper dose modulation.

Molecular mechanisms of serotonergic action of the HIV-1 antiretroviral efavirenz

Efavirenz is highly effective at suppressing HIV-1, and the WHO guidelines list it as a component of the first-line antiretroviral (ARV) therapies for treatment-naïve patients. Though the pharmacological basis is unclear, efavirenz is commonly associated with a risk for neuropsychiatric adverse events (NPAEs) when taken at the prescribed dose. In many patients these NPAEs appear to subside after several weeks of treatment, though long-term studies show that in some patients the NPAEs persist. In a recent study focusing on the abuse potential of efavirenz, its receptor psychopharmacology was reported to include interactions with a number of established molecular targets for known drugs of abuse, and it displayed a prevailing behavioral profile in rodents resembling an LSD-like activity. In this report, we discovered interactions with additional serotonergic targets that may be associated with efavirenz-induced NPAEs. The most robust interactions were with 5-HT3A and 5-HT6 receptors, with more modest interactions noted for the 5-HT2B receptor and monoamine oxidase A. From a molecular mechanistic perspective, efavirenz acts as a 5-HT6 receptor inverse agonist of Gs-signaling, 5-HT2A and 5-HT2C antagonist of Gq-signaling, and a blocker of the 5-HT3A receptor currents. Efavirenz also completely or partially blocks agonist stimulation of the M1 and M3 muscarinic receptors, respectively. Schild analysis suggests that efavirenz competes for the same site on the 5-HT2A receptor as two known hallucinogenic partial agonists (±)-DOI and LSD. Prolonged exposure to efavirenz reduces 5-HT2A receptor density and responsiveness to 5-HT. Other ARVs such as zidovudine, nevirapine and emtricitabine did not share the same complex pharmacological profile as efavirenz, though some of them weakly interact with the 5-HT6 receptor or modestly block GABAA currents.

Rethinking the risk-benefit ratio of efavirenz in HIV-infected children

The non-nucleoside reverse transcriptase inhibitor efavirenz is part of the WHO guidelines for preferred first-line treatment of HIV-1-infected adults, pregnant and lactating women, and children. Efavirenz is well known to cause CNS toxicity. Although good data for CNS toxicity are available for adults, the opposite is true for children. Paediatric studies on this topic frequently suffer from small sample sizes or absence of thorough neuropsychiatric assessments. In this Personal View, we focus on two knowledge gaps of CNS toxicity of efavirenz in children. First, plasma concentrations of efavirenz are difficult to predict in children because of immaturity of and genetic variation in metabolic enzymes. Second, efavirenz exerts a lysergide (LSD)-like effect on brain serotonergic pathways and affects CNS metabolic pathways, including mitochondrial function. Whether these effects interfere with normal brain development is unknown. These uncertainties underline the imminent need for better monitoring of mental health and neurocognitive development in children given and exposed to efavirenz.