Virologic outcomes of HAART with concurrent use of cytochrome P450 enzyme-inducing antiepileptics: a retrospective case control study

Pre- and Post-Exposure Prophylaxis for HIV in Patients Taking Anti-Seizure Medications

The prevention of human immunodeficiency virus (HIV) infection has recently emphasized the use of pre- and post-exposure prophylaxis (PrEP and PEP), both of which were highly effective in prevention of HIV infection. Since the last published guidance regarding the cotreatment of people with anti-seizure medications (ASM) and antiretroviral treatments (ARTs) in 2012, both fields have numerous new medication options. Historically, cotreatment of HIV and seizures could be challenging with increased risk of virologic failure and barriers in access to health care due to global availability, social determinants of health, and stigma of both HIV and seizures. In this narrative review, we describe the data-driven and expected bidirectional pharmacokinetic (PK) interactions between guideline-based PrEP and PEP treatment and ASM, as well as overlapping side effects. There are many ASMs with no known interaction with PrEP or PEP regimens. The interactions focus on enzyme inducing ASMs, valproate, and lamotrigine. Most prominently, enzyme inducing ASMs lower serum levels of tenofovir-containing PrEP regimens and elements of PEP (dolutegravir, raltegravir, and ritonavir), which increased risk of virologic treatment failure in people with HIV but have unclear clinical significance on the effectiveness of PrEP and PEP. In addition, ritonavir treatment in PEP may significantly lower lamotrigine serum levels even during the 4 weeks of treatment, which may increase risk for breakthrough seizures during PEP and skin reactions after discontinuation of ritonavir. In addition to PK interactions, overlapping side effects are common including osteopenia, hepatic toxicity, and other gastrointestinal effects. This narrative review aims to be a resource for all clinicians prescribing ASMs so that they can create a welcoming environment to enable successful treatment of seizures and reduce the risk of HIV infection in people at risk. In addition, we highlight knowledge gaps and areas of unmet need that can be addressed with future studies.

Co-medications and Drug-Drug Interactions in People Living with HIV in Turkey in the Era of Integrase Inhibitors

BACKGROUND

Long life expectancy in people living with human immunodeficiency virus (PLWH) caused an increase in comorbidities and co-medications. We aimed to analyse comedications and drug-drug interactions (DDIs) in antiretroviral therapy (ART)-naive PLWH in the era of integrase inhibitors.

METHODS

A retrospective observational study was conducted between January 2016-August 2019. Patients' characteristics and chronic co-medications were recorded. The University of Liverpool HIV drug interaction database was used for DDIs.

RESULTS

Among 745 patients, the chronic co-medication rate was 30.9%. Older age (p<0.001, OR:6.66, 95% CI: 3.86-11.49) and female gender (p=002, OR:2.25, 95%:1.14-4.44) were independently associated with co-medication. Cardiovascular system (CVS) and central nervous system (CNS) drugs were the most common co-medications. Older age patients (p<0.001, OR:12.04, 95% CI:4.63-36.71), having heterosexual (HS) contact (p=0.003, OR:3.8, 95% CI:1.57-9.22) were independently associated with CVS drugs use, while being men who have sex with men (MSM) (p=0.03, OR:2.59, 95% CI:1.11-6.03) were associated with CNS drugs use. DDIs were seen in 37.4% of patients with co-medications. Antidiabetics (23.3%), CNS (22.1%) and CVS drugs (19.8%) most commonly had DDIs. Contraindication was most commonly seen between inhaled corticosteroids and elvitegravir/cobicistat. A number of non-ART drugs, elvitegravir/cobicistat, antidiabetics, vitamins were independently associated with the presence of DDIs.

CONCLUSION

Results suggested the need for attention about co-medication in PLWH regardless of whether they are young or older. CNS drugs should be questioned more detailed in MSM, as well as CVS drugs in older HS patients. Elvitegravir/cobicistat is significantly associated with DDIs and switching to an unboosted INSTI should be considered in patients with multiple comorbidities.

Evaluating the impact of antiretroviral and antiseizure medication interactions on treatment effectiveness among outpatient clinic attendees with HIV in Zambia

OBJECTIVE

Interactions between enzyme-inducing anti-seizure medications (EI-ASMs) and antiretroviral drugs (ARVs) can lead to decreased ARV levels and may increase the likelihood of viral resistance. We conducted a study to determine if co-usage of ARVs and EI-ASMs is associated with ARV-resistant human immunodeficiency virus (HIV) among people living with HIV in Zambia.

METHODS

Eligible participants were ≥18 years of age and concurrently taking ASMs and ARVs for at least 1 month of the prior 6-month period. Data were obtained regarding medication and HIV history. CD4 counts, plasma viral loads (pVLs), and HIV genotype and resistance profile in participants with a pVL >1000 copies/mL were obtained. Pearson's test of independence was used to determine whether treatment with EI-ASM was associated with pVL >1000/mL copies.

RESULTS

Of 50 participants, 41 (82%) were taking carbamazepine (37 on monotherapy), and all had stable regimens in the prior 6 months. Among the 13 ARV regimens used, 68% had a tenofovir/lamivudine backbone. The majority (94%) were on a stable ARV regimen for >6 months. Median CD4 nadir was 205 cells/mm³ (interquartile range [IQR] 88-389), and 60% of participants had commenced ARV treatment before advanced disease occurred. Mean CD4 count at enrollment was 464 cells/mm³ (SD 226.3). Seven participants (14%) had a CD4 count <200 cells/mm³ . Four (8%) had a pVL >1000 copies/mL; all were on carbamazepine. Three participants with elevated pVL had a CD4 count <200 cells/mm³ . None had documented adherence concerns by providers; however, two had events concerning for clinical failure. HIV genotype testing showed mutations in three participants. Carbamazepine was not found to correlate with elevated pVL (P = .58).

SIGNIFICANCE

EI-ASMs are commonly used in sub-Saharan Africa. Despite concurrent use of EI-ASMs and ARVs, the majority of participants showed CD4 counts >200 cells/mm³ and were virally suppressed. Carbamazepine was not associated with an increased risk of virological failure or ARV-resistant HIV.

Short Communication: Relationship Between Contraindicated Drug-Drug Interactions and Subsequent Hospitalizations Among Patients Living with HIV Initiating Combination Antiretroviral Therapy

Persons living with HIV (PLWH) are at an increased risk of contraindicated drug-drug interactions (XDDIs), which may result in deleterious outcomes. Study objectives were to (1) compare the frequency of hospitalizations between patients with and without XDDIs and (2) determine if XDDIs are independently associated with hospitalizations in PLWH. A retrospective cohort study was performed among PLWH receiving care at the Upstate New York Veterans' Healthcare Administration or University of New Mexico Truman Health Services from 2000 to 2013. Hospitalization was defined as an admission to an inpatient hospital facility for ≥24 h. Of the 1329 patients evaluated, 149 (11.2%) patients were hospitalized within 1 year of antiretroviral therapy initiation. A significantly higher proportion of patients with XDDIs were hospitalized compared with those who did not have XDDIs (20.3% vs. 10.2%, risk ratio: 1.98, 95% confidence interval [CI]: 1.35-2.91, p = .001). In the multivariate Cox proportional hazards regression analyses, XDDIs were independently associated with hospitalizations (hazard ratio [HR]: 1.58; 95% CI: 1.00-2.48; p = .05), after adjustment for CD4 < 242 cells/mm³ (HR: 2.38; 95% CI: 1.72-3.33; p < .001), protease inhibitor (PI)-based regimen (HR: 1.35; 95% CI: 0.97-1.89; p = .08), recreational drug use (HR: 2.58, 95% CI: 1.85-3.58, p < .001), and non-HIV medications ≥10 (HR: 1.62; 95% CI: 0.97-2.69; p = .07). In this study an increased risk of hospitalization was observed among PLWH with XDDIs compared with those without XDDIs. This relationship persisted after adjustment for CD4 count, use of a PI-based regimen, recreational drug use, and number of non-HIV medications.

Prevalence and incidence of new-onset seizures and epilepsy in patients with human immunodeficiency virus (HIV): Systematic review and meta-analysis

BACKGROUND

The prevalence and incidence of seizures are substantially higher in patients with human immunodeficiency virus (HIV) compared with the general population and is associated with higher mortality rates. Despite this, the condition remains poorly understood, and there is variation in reported epidemiological studies. The aim of this systematic review and meta-analysis was to investigate the risk factors associated with seizures in the population with HIV, explore the source of variations, and describe management plans that can aid clinicians in the acute and long-term treatment of these patients.

METHODS

A structured electronic database search of MEDLINE, EMBASE, and Cochrane Library was conducted. Studies were included if they described clinical details of patients with HIV with seizures or epilepsy. We extracted select variables from each included study, and we estimated pooled estimates of the incidence and prevalence of seizures using random-effects meta-analysis of proportions.

RESULTS

Information on 6639 cases of patients with HIV was extracted from 9 included studies. These comprised of 2 studies from the United States of America (USA), 3 from Europe, 3 from Asia, and 1 from Africa. The pooled prevalence and incidence rate of seizures in HIV were 62 per 1000 population and 60 per 1000 population respectively. Among those who presented with new-onset seizures, 63% had seizure recurrence. At the time of first seizure, 82.3% had acquired immunodeficiency syndrome (AIDS). Factors that appeared to be linked to seizures in HIV included advanced HIV disease, opportunistic infections particularly toxoplasmosis, and metabolic derangement. Most seizures were effectively controlled by common antiepileptic drugs (AEDs).

CONCLUSIONS

The prevalence and incidence of seizures and epilepsy in the population with HIV are substantially higher than the general population. Our results suggest that advanced HIV and opportunistic infections are associated with the majority of the seizures. Early initiation of highly active antiretroviral therapy (HAART), prophylactic use of cotrimoxazole (trimethoprim-sulfamethoxazole) and routine electroencephalogram (EEG) in patients with HIV may reduce seizure incidence and frequency and help in early diagnosis of nonconvulsive seizures in this population. We recommend long-term seizure management with AED, and for patients on HAART, enzyme-inducing AED should be avoided when possible.

Global HIV neurology: a comprehensive review

: Neurological conditions associated with HIV remain major contributors to morbidity and mortality and are increasingly recognized in the aging population on long-standing combination antiretroviral therapy (cART). Importantly, growing evidence shows that the central nervous system (CNS) may serve as a reservoir for viral replication, which has major implications for HIV eradication strategies. Although there has been major progress in the last decade in our understanding of the pathogenesis, burden, and impact of neurological conditions associated with HIV infection, significant scientific gaps remain. In many resource-limited settings, antiretrovirals considered second or third line in the United States, which carry substantial neurotoxicity, remain mainstays of treatment, and patients continue to present with severe immunosuppression and CNS opportunistic infections. Despite this, increased global access to cART has coincided with an aging HIV-positive population with cognitive sequelae, cerebrovascular disease, and peripheral neuropathy. Further neurological research in low-income and middle-income countries (LMICs) is needed to address the burden of neurological complications in HIV-positive patients, particularly regarding CNS viral reservoirs and their effects on eradication.

Pharmacokinetic Considerations with the Use of Antiepileptic Drugs in Patients with HIV and Organ Transplants

PURPOSE OF REVIEW

Antiepileptic drugs are frequently administered to patients with HIV infection or in recipients of organ transplants. The potentially serious drug-drug interactions between the "classic" antiepileptic drugs, antiretrovirals, and immunosuppressants have been extensively studied. Evidence-based information on the second and third generation of antiepileptic drugs is almost non-existent. The purpose of this review is to analyze the pharmacokinetic profile of these newer agents to assess their potential for drug interactions with antiretrovirals and immunosuppressants.

RECENT FINDINGS

As a group, the newer generations of antiepileptic drugs have shown a more favorable drug interaction potential compared to the "classic" ones. A group of moderate enzyme-inducing drugs includes eslicarbazepine acetate, oxcarbazepine, rufinamide, and topiramate. These drugs are not as potent inducers as the "classic" drugs but may potentially decrease the serum concentrations of some antiretrovirals and immunosuppressants. Antiepileptic drugs with no or minimal enzyme-inducing properties include brivaracetam, gabapentin, lacosamide, lamotrigine, levetiracetam, perampanel, pregabalin, and vigabatrin. The newer generations of antiepileptic drugs have expanded the therapeutic options in patients with HIV infection or organ transplants.

Analysis of drug-drug interactions among patients receiving antiretroviral regimens using data from a large open-source prescription database

PURPOSE

Results of a study of contraindicated concomitant medication use among recipients of preferred antiretroviral therapy (ART) regimens are reported.

METHODS

A retrospective study was conducted to evaluate concomitant medication use in a cohort of previously treatment-naive, human immunodeficiency virus (HIV)-infected U.S. patients prescribed preferred ART regimens during the period April 2014-March 2015. Data were obtained from a proprietary longitudinal prescription database; elements retrieved included age, sex, and prescription data. The outcome of interest was the frequency of drug-drug interactions (DDIs) associated with concomitant use of contraindicated medications.

RESULTS

Data on 25,919 unique treatment-naive patients who used a preferred ART regimen were collected. Overall, there were 384 instances in which a contraindicated medication was dispensed for concurrent use with a recommended ART regimen. Rates of contraindicated concomitant medication use differed significantly by ART regimen; the highest rate (3.2%) was for darunavir plus ritonavir plus emtricitabine-tenofovir disoproxil fumarate (DRV plus RTV plus FTC/TDF), followed by elvitegravir-cobicistat-emtricitabine-tenofovir disoproxil fumarate (EVG/c/FTC/TDF)(2.8%). The highest frequencies of DDIs were associated with ART regimens that included a pharmacoenhancing agent: DRV plus RTV plus FTC/TDF (3.2%) and EVG/c/FTC/TDF (2.8%).

CONCLUSION

In a large population of treatment-naive HIV-infected patients, ART regimens that contained a pharmacoenhancing agent were involved most frequently in contraindicated medication-related DDIs. All of the DDIs could have been avoided by using therapeutic alternatives within the same class not associated with a DDI.

Global developments in HIV neurology

Neurologic conditions associated with HIV remain major contributors to morbidity and mortality, and are increasingly recognized in the aging population on long-standing combination antiretroviral therapy (cART). Importantly, growing evidence suggests that the central nervous system (CNS) serves as a reservoir for viral replication with major implications for human immunodeficiency virus (HIV) eradication strategies. Though there has been major progress in the last decade in our understanding of the pathogenesis, burden, and impact of HIV-associated neurologic conditions, significant scientific gaps remain. In many low-income settings, second- and third-line cART regimens that carry substantial neurotoxicity remain treatment mainstays. Further, patients continue to present severely immunosuppressed with CNS opportunistic infections. Public health efforts should emphasize improvements in access and optimizing treatment of HIV-positive patients, specifically in resource-limited settings, to reduce the risk of neurologic sequelae.

Patient-Reported Adverse Effects Associated with Combination Antiretroviral Therapy and Coadministered Enzyme-Inducing Antiepileptic Drugs

AbstractConcurrent treatment with combination antiretroviral therapy (cART) and an enzyme-inducing antiepileptic drug (EI-AED) is common in resource-limited settings; however, the incidence and impact of adverse effects in cotreated patients is largely unknown. Symptoms of adverse effects were assessed by both spontaneous report and checklist for 145 human immunodeficiency virus (HIV)-infected Zambian adults initiating various treatment combinations, such as cART with an EI-AED (N = 20), cART only (N = 43), or neither drug (untreated; N = 82). At study baseline, the cART + EI-AED group reported more headache, generalized fatigue, problems with concentration, and depression than the untreated group (P < 0.01 for all). At 2 weeks, a greater proportion of cART + EI-AED participants reported increased nausea or vomiting compared with baseline (P < 0.05). Adverse effects did not appear to impact self-reported adherence at 2 weeks as 100% cART adherence was reported in 19 of 20 (95%) and 42 of 43 (98%) cART + EI-AED and cART-only participants, respectively; 100% EI-AED adherence was reported in 19 of 20 (95%) participants. However, adherence at 6 months was suboptimal in both groups with 18 of 33 (56%) participants on cART experiencing greater than 1-week lapse in pharmacy-reported medication supply. Our results highlight the need to educate patients about the increased potential for nausea and vomiting with cART + EI-AED cotreatment. Although adherence was high early during treatment, adherence should be reinforced overtime to minimize the potential for HIV and/or epilepsy treatment failure.

Predictors and characteristics of seizures in survivors of progressive multifocal leukoencephalopathy

This study aims to determine the risk factors for epileptogenesis and characteristics of seizures in patients with progressive multifocal leukoencephalopathy (PML) who survive more than 1 year from onset of neurological symptoms (PML survivors). We reviewed clinical data including seizure history and MR imaging studies from PML survivors evaluated at our institution between 1997 and 2014. PML progressors who passed away within 1 year and patients with a history of seizures prior to PML diagnosis were excluded from the analysis. Of 64 PML survivors, 28 (44 %) developed seizures. The median time from the onset of PML symptoms to the first seizure was 5.4 months (range 0-159) and 64 % of patients with seizures had them within the first year. The presence of juxtacortical PML lesions was associated with a relative risk of seizures of 3.5 (p < 0.02; 95 % confidence interval (CI) 1.3-9.4) in multivariate analyses. Of all seizure types, 86 % were focal and 60 % most likely originated from the frontal lobes. Among seizure patients, 89 % required treatment, including one (54 %), two (25 %), or three (10.5 %) antiepileptic drugs. Seizures are a frequent complication in PML and can develop throughout the entire course of the disease. However, late onset seizures did not signify PML relapse. Seizures may require treatment with multiple antiepileptic medications and are a significant co-morbidity in PML.

Lifelong antiretroviral therapy or HIV cure: The benefits for the individual patient

There are an estimated 35 million people living with human immunodeficiency virus (HIV) globally, 19 million of whom are unaware of their HIV status and, in the absence of antiretroviral therapy (ART), will have a shortened life expectancy. Although ART remains the "gold standard" for treatment of HIV infection, the requirement for lifelong treatment poses multiple challenges for the patient. These include stigma, an untenable pill burden, side effects, and the threat of viral resistance in the case of non-compliance. This review evaluates the challenges of accessing, delivering, and sustaining ART for people living with HIV and will discuss the case for pursuing a goal of HIV cure, the potential benefits of such a cure for the individual patient, and the current potential candidates for such a cure.

Safe Treatment of Seizures in the Setting of HIV/AIDS

OPINION STATEMENT

HIV(+) patients are at increased risk for developing seizures due to the vulnerability of the central nervous system to HIV-associated diseases, immune dysfunction, and metabolic disturbances. In patients with acute seizures, standard protocols still apply with urgent seizure cessation being the priority. Management of the person with established epilepsy who contracts HIV is challenging, but the decision to initiate chronic antiepileptic drug (AED) therapy in an HIV(+) patient is also difficult. Chronic treatment guidelines emphasize the interactions between AEDs and antiretroviral (ARV) medications, but provide no explicit advice regarding when to initiate an AED, what medication to select, and/or the duration of treatment. Epidemiologic data regarding seizure recurrence risk in HIV(+) individuals is not available. The risk of further seizures likely depends upon the underlying etiology for the seizure(s) and patients' immune status and may be increased by the use of efavirenz (an ARV). The issues for consideration include AED-ARV interactions, organ dysfunction, seizure type, and drug side effects, which may worsen or be confused with symptoms of HIV and/or epilepsy. Co-administration of enzyme inducing (EI)-AEDs and ARVs can result in virological failure, breakthrough seizure activity, AED toxicity, and/or ARV toxicity. Where available, the AED of choice in HIV(+) patients is levetiracetam due to its broad spectrum activity, ease of use, minimal drug interactions, and favorable side effect profile. Lacosamide, gabapentin, and pregabalin are also favored choices in patients with partial onset seizures and/or those failing levetiracetam. Where newer AEDs are not available, valproic acid may be the treatment of choice in terms of an AED, which will not cause enzyme induction-associated ARV failure, but its side effect profile causes other obvious problems. In resource-limited settings (RLS) where only EI-AEDs are available, there are no good treatment options and further pressure needs to be placed upon policymakers to address this care gap and public health threat.

The impact of enzyme-inducing antiepileptic drugs on antiretroviral drug levels: a case-control study

PURPOSE

To evaluate the impact of enzyme-inducing antiepileptic drugs (EI-AEDs) on serum antiretroviral (ARV) levels in patients with HIV.

METHODS

Data from the U.S. Military HIV Natural History Study were screened to identify participants taking ARVs with EI-AEDs and controls taking ARVs with non enzyme-inducing AEDs (NEI-AEDs). The proportion of serum ARV levels below the recommended minimum concentrations (C(min)) was compared between these groups.

RESULTS

ARV levels were available for 10 individuals exposed to 16 intervals on combined ARVs/EI-AEDs (phenytoin and carbamazepine) and for 25 controls exposed to 30 overlap intervals on combined ARVs/NEI-AEDs. The percentage of overlap intervals with ≥1 ARV levels below C(min) was higher in the EI-AED group than in controls (37.5% vs. 23.3%; p=0.124). After excluding intervals associated with serum levels of EI-AEDs below the reference range (n=6), the proportion of intervals with ≥1 ARV level below C(min) was significantly greater among EI-AED recipients (60%) compared to controls (23.3%; p=0.008).

CONCLUSIONS

ARV levels below C(min) were more common in participants receiving EI-AEDs, the difference being statistically significant for intervals associated with EI-AED levels within the reference range. These data suggest that, in agreement with current guidelines, EI-AEDs should be avoided in patients receiving ARV therapy.

Evidence-based guideline: Antiepileptic drug selection for people with HIV/AIDS: report of the Quality Standards Subcommittee of the American Academy of Neurology and the Ad Hoc Task Force of the Commission on Therapeutic Strategies of the International League Against Epilepsy

OBJECTIVE

To develop guidelines for selection of antiepileptic drugs (AEDs) among people with HIV/AIDS.

METHODS

The literature was systematically reviewed to assess the global burden of relevant comorbid entities, to determine the number of patients who potentially utilize AEDs and antiretroviral agents (ARVs), and to address AED-ARV interactions.

RESULTS AND RECOMMENDATIONS

AED-ARV administration may be indicated in up to 55% of people taking ARVs. Patients receiving phenytoin may require a lopinavir/ritonavir dosage increase of ~50% to maintain unchanged serum concentrations (Level C). Patients receiving valproic acid may require a zidovudine dosage reduction to maintain unchanged serum zidovudine concentrations (Level C). Coadministration of valproic acid and efavirenz may not require efavirenz dosage adjustment (Level C). Patients receiving ritonavir/atazanavir may require a lamotrigine dosage increase of ∼50% to maintain unchanged lamotrigine serum concentrations (Level C). Coadministration of raltegravir/atazanavir and lamotrigine may not require lamotrigine dosage adjustment (Level C). Coadministration of raltegravir and midazolam may not require midazolam dosage adjustment (Level C). Patients may be counseled that it is unclear whether dosage adjustment is necessary when other AEDs and ARVs are combined (Level U). It may be important to avoid enzyme-inducing AEDs in people on ARV regimens that include protease inhibitors or nonnucleoside reverse transcriptase inhibitors, as pharmacokinetic interactions may result in virologic failure, which has clinical implications for disease progression and development of ARV resistance. If such regimens are required for seizure control, patients may be monitored through pharmacokinetic assessments to ensure efficacy of the ARV regimen (Level C).