Triple-combination rilpivirine, emtricitabine, and tenofovir (Complera™/Eviplera™) in the treatment of HIV infection

Rilpivirine as a potential candidate for the treatment of HIV-associated neurocognitive disorders (HAND)

As the HIV epidemic continues to contribute to global morbidity and mortality, the prevalence of HIV-associated neurological disorders (HAND) also continues to be a major concern in infected individuals, despite the widespread use of combination antiretroviral therapy. Therefore, current antiretroviral drugs should be able to reach therapeutic levels in the brain for the treatment of HAND. The brain distribution of the next-generation non-nucleoside reverse transcriptase inhibitor, rilpivirine (RPV) was investigated in healthy female Sprague-Dawley (SD) rats. The presented study involves the use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) to estimate the concentrations of RPV in plasma and brain homogenate samples. The use of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) provided regional spatial distribution of RPV in brain tissue sections. The localization of RPV was found to be relatively high in the hypothalamus, thalamus and corpus callosum, brain regions known to be associated with neurodegeneration during HAND (including the cerebral cortex). This study has shown that RPV has an excellent blood-brain barrier penetrability. Thus, in combination with other antiretroviral drugs, better central nervous system (CNS) protection against HAND can possibly be achieved.

Accumulated pre-switch resistance to more recently introduced one-pill-once-a-day antiretroviral regimens impacts HIV-1 virologic outcome

BACKGROUND

One-pill-once-a-day regimens (OPODs) appeal to providers and patients. The impact of resistance to OPODs in routine clinical care is important yet unclear, particularly in treatment-experienced patients.

OBJECTIVES

We hypothesized that resistance to any OPOD component impacts treatment success and that historical, vs. most recent, resistance better predicts it.

STUDY DESIGN

In the largest RI HIV Center, we identified all patients starting/switching to Complera/Stribild, evaluated their 12-month viral load (VL) suppression, and examined the impact of demographic, clinical and laboratory data on it, focusing on recent-only vs. accumulated significant resistance, defined as low-, intermediate- or high-level predicted resistance to any OPOD component. Associations with outcomes were evaluated using Fisher exact and Wilcoxon rank sum tests. Hypotheses were tested using logistic regression.

RESULTS

Of 1624 patients, 224 started/switched to Complera or Stribild, mean age 44 years, 8 years post-diagnosis, CD4 468 cells/μL; 183 treatment-experienced (140 with genotypes; 61% suppressed at switch). Significant OPOD-associated resistance was in 30% by recent-only genotypes, and 38% by all genotypes. 12-month VL suppression was in 83% of treatment-experienced participants: 96% of suppressed at switch, associated with older age, higher CD4, fewer prior genotypes, less accumulated resistance, and better adherence; and 61% of unsuppressed at switch, associated with better adherence. Accumulated resistance independently predicted 12-month failure, better than most-recent resistance only.

CONCLUSION

12-month VL suppression with Complera/Stribild was high, suggesting that OPODs remain options even for experienced patients. Clinicians should consider resistance history before switching to OPODs and continue to focus on improving adherence.

Discontinuation of Initial Antiretroviral Therapy in Clinical Practice: Moving Toward Individualized Therapy

Supplemental Digital Content is Available in the Text.

Background:

Study aim was to estimate the rate and identify predictors of discontinuation of first combination antiretroviral therapy (cART) in recent years.

Methods:

Patients who initiated first cART between January 2008 and October 2014 were included. Discontinuation was defined as stop of at least 1 drug of the regimen, regardless of the reason. All causes of discontinuation were evaluated and 3 main endpoints were considered: toxicity, intolerance, and simplification. Predictors of discontinuation were examined separately for all 3 endpoints. Kaplan–Meier analysis was used for the outcome discontinuation of ≥1 drug regardless of the reason. Cox regression analysis was used to identify factors associated with treatment discontinuation because of the 3 reasons considered.

Results:

A total of 4052 patients were included. Main reason for stopping at least 1 drug were simplification (29%), intolerance (21%), toxicity (19%), other causes (18%), failure (8%), planned discontinuation (4%), and nonadherence (2%). In a multivariable Cox model, predictors of discontinuation for simplification were heterosexual transmission (P = 0.007), being immigrant (P = 0.017), higher nadir lymphocyte T CD4⁺ cell (P = 0.011), and higher lymphocyte T CD8⁺ cell count (P = 0.025); for discontinuation due to intolerance: the use of statins (P = 0.029), higher blood glucose levels (P = 0.050). About toxicity: higher blood glucose levels (P = 0.010) and the use of zidovudine/lamivudine as backbone (P = 0.044).

Conclusions:

In the late cART era, the main reason for stopping the initial regimen is simplification. This scenario reflects the changes in recommendations aimed to enhance adherence and quality of life, and minimize drug toxicity.

Impact of Depression and Inflammation on the Progression of HIV Disease

The human immunodeficiency virus type 1 (HIV-1) epidemic has negatively affected over 40 million people worldwide. Antiretroviral therapy (ART) has improved life expectancy and changed the outcome of HIV-1 infection, making it a chronic and manageable disease. However, AIDS and non-AIDS comorbid illnesses persist during the course of infection despite the use of ART. In addition, the development of neuropsychiatric comorbidities (including depression) by HIV-infected subjects significantly affects quality of life, medication adherence, and disease prognosis. The factors associated with depression during HIV-1 infection include altered immune response, the release of pro-inflammatory cytokines, and monoamine imbalance. Elevated plasma pro-inflammatory cytokine levels contribute to the development of depression and depressive-like behaviors in HIV⁺ subjects. In addition, comorbid depression influences the decline rates of CD4⁺ cell counts and increases plasma viral load. Depression can manifest in some subjects despite their adherence to ART. In addition, psychosocial factors related to stigma (negative attitudes, moral issues, and abuse of HIV⁺ subjects) are also associated with depression. Both neurobiological and psychosocial factors are important considerations for the effective clinical management of HIV and the prevention of HIV disease progression.

Emtricitabine/rilpivirine/tenofovir disoproxil fumarate single-tablet regimen: a review of its use in HIV infection

The nucleos(t)ide reverse transcriptase inhibitors, emtricitabine and tenofovir disoproxil fumarate (tenofovir DF), and the non-nucleoside reverse transcriptase inhibitor, rilpivirine, are now available as a fixed-dose single-tablet regimen (emtricitabine/rilpivirine/tenofovir DF; Complera(®), Eviplera(®)) for the treatment of adults infected with HIV-1. In treatment-naïve adults, once-daily emtricitabine/rilpivirine/tenofovir DF was noninferior to once-daily emtricitabine/efavirenz/tenofovir DF with regard to establishing virological suppression over 96 weeks of therapy in a randomized, open-label, phase IIIb study (STaR). These data confirmed the findings of a pooled subset analysis of two earlier 96-week, double-blind, phase III trials (ECHO and THRIVE) in which treatment-naïve adults received either rilpivirine or efavirenz in combination with emtricitabine/tenofovir DF. However, the virological benefit of emtricitabine/rilpivirine/tenofovir DF in this setting appeared limited in patients with low CD4+ cell counts or high viral loads at baseline. In 48-week phase IIIb (SPIRIT) and IIb (Study 111) trials in treatment-experienced patients already virologically suppressed with a single- or multiple-tablet antiretroviral regimen and without prior virological failure, switching to once-daily emtricitabine/rilpivirine/tenofovir DF maintained virological suppression and was noninferior to remaining on a more complex multiple-tablet regimen in this regard. Emtricitabine/rilpivirine/tenofovir DF is generally well tolerated and appears to have a more favourable tolerability profile than emtricitabine/efavirenz/tenofovir DF. Thus, emtricitabine/rilpivirine/tenofovir DF is a welcome addition to the other single-tablet regimens currently available for the treatment of HIV-1 infection, providing a convenient and effective option for some adults who are treatment-naïve, as well as those who are already virologically suppressed on their current treatment regimen and wish to switch because of intolerance or to simplify their regimen.

HIV-associated lipodystrophy: impact of antiretroviral therapy

In the late 1990s, reports of unusual changes in body fat distribution named 'lipodystrophy' (LD) began to appear in HIV patients mitigating the enormous enthusiasm about improvement of survival and quality of life provided by the combinations of antiretroviral (ARV) drug classes, the so-called highly active antiretroviral therapy (HAART), which had just become available at that time. The objective of this paper is to critically review the literature on LD and to discuss the impact of newer ARV agents, namely atazanavir, darunavir and raltegravir, as well as strategies of the late HAART era, including single-tablet regimens and nucleoside-sparing regimens. Studies in which LD was measured by dual-energy x-ray absorptiometry or by abdominal computed tomography or magnetic resonance imaging scan only, were included. We were unable to identify studies depicting a negative impact of drugs or ARV regimens on limb fat loss. On the contrary, a few studies identified a negative impact of atazanavir/ritonavir or darunavir/ritonavir on trunk fat increase. It should be noted that this anthropometric measure is a poor instrument since it cannot distinguish between subcutaneous and visceral fat. We conclude that presumably the body fat changes currently observed in HIV-infected patients is the net result of competing phenomena: on one side the natural history of lipohypertrophy as a result of HIV and HAART impact, and on the other side the physiological body fat changes observed in the aging population.

Pain without nociceptors? Nav1.7-independent pain mechanisms

Nav1.7, a peripheral neuron voltage-gated sodium channel, is essential for pain and olfaction in mice and humans. We examined the role of Nav1.7 as well as Nav1.3, Nav1.8, and Nav1.9 in different mouse models of chronic pain. Constriction-injury-dependent neuropathic pain is abolished when Nav1.7 is deleted in sensory neurons, unlike nerve-transection-related pain, which requires the deletion of Nav1.7 in sensory and sympathetic neurons for pain relief. Sympathetic sprouting that develops in parallel with nerve-transection pain depends on the presence of Nav1.7 in sympathetic neurons. Mechanical and cold allodynia required distinct sets of neurons and different repertoires of sodium channels depending on the nerve injury model. Surprisingly, pain induced by the chemotherapeutic agent oxaliplatin and cancer-induced bone pain do not require the presence of Nav1.7 sodium channels or Nav1.8-positive nociceptors. Thus, similar pain phenotypes arise through distinct cellular and molecular mechanisms. Therefore, rational analgesic drug therapy requires patient stratification in terms of mechanisms and not just phenotype.

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Phenotypically identical pain models have different underlying molecular mechanisms

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Nav1.7 expression is required for sympathetic sprouting after neuronal damage

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Oxaliplatin and cancer-induced bone pain are both Nav1.7-independent

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Deleting Nav1.7 in adult mice reverses nerve damage-induced neuropathic pain