Association of Human Leukocyte Antigen Alleles and Hypersensitivity of Efavirenz/Nevirapine in HIV-Infected Chinese Patients.

To examine the association between human leukocyte antigen (HLA) and nevirapine (NVP)- and efavirenz (EFV)-induced cutaneous adverse reactions in human immunodeficiency virus (HIV) patients, we conducted a case-control study at our center consisting of 96 patients. Patients were further assigned based on the occurrence of cutaneous adverse events and the drugs involved. All patients were subjected to next generation sequencing (NGS)-based screening with focus on HLA phenotype, including the presence of HLA-B, HLA-C, and HLA-DRB1. Our data indicated that the HLA-C*01:02:01 allele presence was observed in 47.4% (18/38) of patients in the EFV-hypersensitivity group compared with 18.9% (7/30) in the control group [odds ratio (OR) = 5.837; 95% confidence interval (CI) = 1.727-19.722, p = .005]. In contrast, the occurrence of HLA-DRB1*08:03 was found to be significantly lower in the EFV-hypersensitivity group (4/38, 10.5%) compared with the corresponding control group (12/37, 32.4%) (OR = 0.148; 95% CI = 0.035-0.625, p = .009). In addition, the HLA-DRB1*04:05:01 antigen was expressed more frequently in the NVP-hypersensitivity group (23.8%, 5/21) compared with the control group (10.8%, 4/37) (OR = 7; 95% CI = 1.265-38.793, p = .026). Our data not only revealed a significant association between HLA-C*01:02:01 and EFV-induced cutaneous adverse reactions but may also shed light on defining the treatment for Chinese HIV patients.

Cutaneous adverse drug reactions among people living with human immunodeficiency virus in a tertiary care hospital in Johor, Malaysia.

BACKGROUND: Cutaneous adverse drug reactions (cADRs) among people living with HIV (PLWH) are common. Data on drug eruptions among PLWH in Malaysia are limited. Thus, our study aimed to determine the clinical patterns of cADRs among PLWH and the risk factors associated with severe cutaneous adverse reactions (SCAR). METHODS: A cross-sectional study was conducted among PLWH who developed cADRs presenting to our dermatology clinic from June 2020 to December 2020. The Naranjo scale was used for drug causality assessment. RESULTS: A total of 78 PLWH were recruited with a male-to-female ratio of 12:1. The maculopapular eruption was the commonest type of cADRs (75.6%), followed by drug reaction with eosinophilia and systemic symptoms (DRESS) (15.4%). SCAR is defined as a potentially life-threatening, immunologically mediated, drug-induced disease, accounting for 17.9% of the cases. Most of the patients were on antiretroviral therapy (ART) (85.9%), with efavirenz + tenofovir/emtricitabine being the most common combination (80.6%). Efavirenz (51.3%) was the main culprit drug implicated, followed by trimethoprim/sulfamethoxazole (23.1%) and nevirapine (11.5%). CD4 T-cell count <100 cells/µL (p = 0.006) was the independent risk factor for SCAR. Most cases had probable causal relationships with the culprit drugs (84.6%) and were not preventable (93.6%). CONCLUSIONS: The commonest cADR seen in PLWH was maculopapular eruption, while efavirenz, trimethoprim/sulfamethoxazole, and nevirapine were the three main implicated drugs. Most of the cases had probable drug causality and were not preventable. PLWH with CD4 count <100 cells/µL were particularly at risk of developing SCAR. Overall, this study showed that immune suppression and polypharmacy as a consequence of opportunistic infection prophylaxis are important factors contributing to the increased risk of ADRs among PLWH.

Safety of 6-week Neonatal Triple-combination Antiretroviral Postexposure Prophylaxis in High-risk HIV-exposed Infants.

BACKGROUND: Combination antiretroviral drug regimens are increasingly preferred for neonatal postexposure prophylaxis (PEP) among HIV-exposed infants with high-risk of transmission. We evaluated the adverse events associated with the use of zidovudine (ZDV)/lamivudine (3TC)/nevirapine (NVP) for neonatal PEP during the first 6 weeks of life. METHODS: A prospective cohort of non-breast-fed HIV-exposed infants was conducted at 5 clinical sites in Thailand. Study population included 100 high-risk HIV-exposed infants (maternal HIV RNA > 50 copies/mL prior to delivery or received antiretroviral therapy less than 12 weeks) and 100 low-risk HIV-exposed neonates. High-risk infants received ZDV/3TC/NVP for 6 weeks whereas low-risk HIV-exposed neonates received a 4-week regimen of ZDV. Complete blood count, aspartate transaminase and alanine transaminase were assessed at birth, 1, 2 and 4 months of life. RESULTS: From October 2015 to November 2017, 200 infants were enrolled, of which 18.5% had low birth weight < 2500 g. The proportion of infants with anemia grade 2 or higher at 1 and 2 months of life between ZDV/3TC/NVP and ZDV prophylaxis was 48.5% vs 32.3% (P=0.02); nevertheless, severe anemia (grade 3) was not significantly different; 9.2% vs 10.2% (P=0.81), respectively. At 1 month old, infants on ZDV/3TC/NVP prophylaxis had significantly higher grade 2 anemia versus infants on ZDV alone (33.0% vs 13.4%; P=0.001); however, no difference was observed at 2 months old. No differences in neutropenia or hepatotoxicity between infant prophylactic regimens were observed. CONCLUSIONS: Triple antiretroviral neonatal PEP with ZDV/3TC/NVP for 6 weeks in high-risk HIV-exposed infants did not significantly increase the risk of short-term toxicity compared with ZDV-monotherapy prophylaxis.

Changes in Lipid Indices in HIV+ Cases on HAART.

We assess long-term changes in lipid levels in human immunodeficiency disease- (HIV-) infected patients undergoing highly active antiretroviral treatment (HAART) and their association with diabetes mellitus (DM) and thyroid dysfunction. We observed changes in the levels of total cholesterol (TC) and total triglyceride (TG) of 63 HIV-infected patients in the 6 years from starting HAART and analyzed correlations between relevant parameters. TC levels of patients with normal baseline TC levels as well as those diagnosed with DM or impaired fasting glucose (IFG) increased significantly (P < 0.05) as did the TG levels of patients with normal baseline TG levels (P < 0.05). TC levels of patients with hypercholesterolemia in the year HAART was initiated were significantly higher than those of patients with normal baseline TC levels (P < 0.05) for all 6 years. TC levels of patients diagnosed with DM were significantly higher than those with euglycemia (P < 0.05) 2 and 4 years after HAART commencement. Levels of TC, high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) were correlated negatively with viral load, whereas levels of TC and very-low-density lipoprotein-cholesterol (VLDL-C) were correlated positively with CD4+ cell counts before HAART commencement. Linear mixed-effect model demonstrated disturbance of glucose metabolism and HAART containing nevirapine and CD4+ cell count were positively correlated with TC levels after HAART commencement. These findings suggest that there are changes in the lipid levels of patients undergoing HAART, with the potential risk of dyslipidemia.

Clinical and genetic factors associated with increased risk of severe liver toxicity in a monocentric cohort of HIV positive patients receiving nevirapine-based antiretroviral therapy.

BACKGROUND: Nevirapine has been used as antiretroviral agent since early '90. Although nevirapine is not currently recommended in initial anti-HIV regimens, its use remains consistent in a certain number of HIV-1-positive subjects. Thus, our aim was to determine clinical and genetic factors involved in the development of severe nevirapine induced liver toxicity. METHODS: We retrospectively analyzed all HIV positive patients who were followed at the Infectious Diseases Unit, DIBIC Luigi Sacco, University of Milan from May 2011 to December 2015. All patients treated with nevirapine who underwent a genotyping for the functional variants mapping into ABCB1, CYP2B6, CYP3A4 and CYP3A5 genes were included in the analysis. Severe hepatotoxicity was defined as ACTG grade 3-4 AST/ALT increase during the first three months of nevirapine treatment. The causality assessment between NVP exposure and drug-induced liver injury was performed by using the updated Roussel Uclaf Causality Assessment Methods. Hardy Weinberg equilibrium was tested by χ2 test. A multivariable logistic regression model was constructed using a backward elimination method. RESULTS: Three hundred and sixty-two patients were included in the analysis, of which 8 (2.2%) experienced a severe liver toxicity. We observed no differences between patients with and without liver toxicity as regards gender, ethnicity, age and immune-virological status. A higher prevalence of HCV coinfection (75.0% vs 30.2%; p = .0013) and higher baseline AST (58 IU/L vs 26 IU/L; p = 0.041) and ALT (82 IU/L vs 27 IU/L; p = 0.047) median levels were observed in patients with liver toxicity vs those without toxicity. The genotypes CT/TT at ABCB1 rs1045642 single nucleotide polymorphism (SNP), showed a protective effect for liver toxicity when compared with genotype CC (OR = 0.18, 95%CI 0.04-0.76; p = 0.020) in univariate analysis. In the multivariate model, HCV coinfection was independently associated with higher risk of developing liver toxicity (aOR = 8.00, 95%CI 1.27-50.29; p = 0.027), whereas ABCB1 rs1045642 CT/TT genotypes (aOR = 0.10, 95%CI 0.02-0.47; p = 0.004) was associated with a lower risk. CONCLUSIONS: According to our findings HCV coinfection and ABCB1 rs1045642 SNP represent independent determinants of severe liver toxicity related to nevirapine. This genetic evaluation could be included as toxicity assessment in HIV-1-positive subjects treated with nevirapine.

Effect of long-term administration of antiretroviral drugs (Tenofovir and Nevirapine) on neuroinflammation and neuroplasticity in mouse hippocampi.

The use of combination antiretroviral therapy (cART) has been successful in suppressing HIV-1 replication and restoring peripheral immune functioning in HIV-infected individuals. Despite these advances in the management of HIV, neurocognitive impairments continue to be diagnosed in HIV-infected patients on treatment, even when the viral load is low. Of interest is the observation that deficiencies in brain function in these individuals are marked by a persistent presence of neuroinflammation. Therefore, in this study we investigated whether long-term exposure to ART could contribute to neuroinflammation. Mice were subsequently administered a daily single dose of either Tenofovir disoproxil fumarate or Nevirapine orally for 8 weeks. After treatment, hippocampal tissue was collected from the brains of drug-treated and control mice and the levels of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and brain-derived neurotrophic factor (BDNF) determined. Our results showed that administration of Tenofovir disoproxil fumarate and Nevirapine induced astrogliosis and up-regulated IL-1ß and TNF-α. In addition, we found that Nevirapine reduced the expression of BDNF. Together these results suggest that Nevirapine promotes inflammatory and reduces neuroprotective processes in the hippocampus of mice. Our findings therefore highlight the potential of ART to be harmful to the brain and as such these drugs may contribute to the development of HIV-associated neurocognitive disorder (HAND).

Non-nucleoside reverse transcriptase inhibitors (NNRTIs)-induced Stevens-Johnson syndrome and gynecomastia in an HIV-infected child: A case report.

BACKGROUND: Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are antiretroviral drugs often used in the first-line treatment regimen of HIV1 infection worldwide. We report a case of successive gynecomastia and Stevens-Johnson syndrome (SJS) respectively induced by efavirenz and nevirapine in a single patient. CASE REPORT: A 16-year-old boy, HIV1-infected since birth, was started on antiretroviral treatment (ART) in August 2015 and was taking a regimen comprising abacavir, lamivudine and efavirenz. In April 2016, when his weight reached 35kg, abacavir was replaced with tenofovir. Bilateral breast enlargement, previously hidden by the patient, was diagnosed two years after the start of ART. History-taking, physical examination and laboratory tests ruled out known causes of gynecomastia, and efavirenz was thus considered the most likely cause. This drug was then withdrawn and replaced with nevirapine in July 2017. Thirty-three days after the patient started nevirapine treatment, a skin rash appeared. Physical examination revealed erythematous macules and flaccid bullae with estimated skin detachment of 10%. There were also conjunctival, buccal and genital lesions. A diagnosis was made of SJS induced by nevirapine. Three months after withdrawal of efavirenz, breast size decreased by 3cm on the left breast and 2cm on the right breast; two months after the SJS, cutaneous sequelae alone persisted, such as diffuse hyperchromic macules. DISCUSSION: Recognition of gynecomastia as a side-effect of efavirenz is important to allow the condition to be treated while it is still potentially reversible. Moreover, when efavirenz is replaced, a protease inhibitor should be preferred to nevirapine.

HBV, HCV, and HBV/HCV co-infection among HIV-positive patients in Hunan province, China: Regimen selection, hepatotoxicity, and antiretroviral therapy outcome.

Co-infection with hepatitis B (HBV) and C (HCV) is common among people living with HIV (PLHIV). This study investigates the impacts of hepatitis co-infection on antiretroviral therapy (ART) outcomes and hepatotoxicity in PLHIV. The cohort study included 1984 PLHIV. Hepatotoxicity was defined by elevated alanine aminotransferase (ALT) levels. ART outcomes were measured by CD4 cell counts, viral load, and mortality rate in patients. Among 1984 PLHIV, 184 (9.3%) were co-infected with HBV and 198 (10.0%) with HCV and 54 (2.7%) were co-infected with HBV and HCV. Of these patients, 156 (7.9%) had ALT elevation ≥ grade 1 at baseline. During the course of ART, the mortality rate and its adjusted hazard ratio (AHR) in PLHIV who were co-infected with HCV (2.6/100 person-years [py], AHR = 2.3, 95%CI 1.1-4.7) was higher than for patients with mono-infected HIV, as it was for those with an elevated ALT (4.4/100 py, AHR = 3.8, [1.7-8.2]) at baseline compared to those with normal ALT. After 6-12 months of ART, the incidence of hepatotoxicity among all the patients was 3.7/100 py. The risk of hepatotoxicity was higher in HCV co-infected (18.6/100 py, adjusted odds ratio [AOR] = 12.4, [8.1-18.2]) than HIV mono-infected patients, and for all regimens (nevirapine: 30.0/100 py, 34.2, 7.3-47.9; zidovudine/stavudine: 24.7/100 py, 22.1, 7.1-25.5; efavirenz: 14.5/100 py, 9.4, 3.5-19.2; lopinavir/ritonavir: 40.1/100 py, 52.2, 9.5-88.2) except tenofovir (4.3/100 py, 4.9, 0.8-9.5). Patients with HBV/HCV co-infected had high hepatotoxicity (10.0/100 py, 6.3, 1.2-23.3) over the same period. Patients with HCV co-infection and HBV/HCV co-infection demonstrated higher hepatotoxicity rate compared with HIV mono-infected patients in China.

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

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

Nevirapine patch testing in Thai human immunodeficiency virus infected patients with nevirapine drug hypersensitivity.

BACKGROUND: Antiretroviral drug hypersensitivity in HIV patients is common. Publications have shown that Abacavir (ABC) patch testing is useful in confirming ABC hypersensitivity in 24-50% of cases with a 100% sensitivity of HLA-B*5701 in patch test positive cases. However, Nevirapine (NVP) patch testing has not been reported. OBJECTIVES: (1) To evaluate the usefulness and safety of NVP patch testing in Thai HIV patients with NVP hypersensitivity. (2) To assess the correlation of positive patch tests with HLA-B*3505. PATIENTS AND METHODS: Patients were classified into two groups: (1) study group of 20 HIV NVP hypersensitivity patients and (2) control group of 15 volunteers without NVP hypersensitivity. Both groups were patch tested with purified and commercialized form of NVP in various vehicles. RESULTS: Two HIV patients with NVP hypersensitivity were patch test positive. All controls tested negative. Three HIV patients were positive for HLA-B*3505 and the two patients with positive patch testing were both HLA-B*3505 positive. CONCLUSIONS: NVP patch testing in Thai HIV patients is safe and can be used to help confirm the association between NVP and hypersensitivity skin reactions. NVP patch test results significantly correlated with HLA-B*3505. The sensitivity of HLA-B*3505 for positive patch test was 100%.

Shared peptide binding of HLA Class I and II alleles associate with cutaneous nevirapine hypersensitivity and identify novel risk alleles.

Genes of the human leukocyte antigen (HLA) system encode cell-surface proteins involved in regulation of immune responses, and the way drugs interact with the HLA peptide binding groove is important in the immunopathogenesis of T-cell mediated drug hypersensitivity syndromes. Nevirapine (NVP), is an HIV-1 antiretroviral with treatment-limiting hypersensitivity reactions (HSRs) associated with multiple class I and II HLA alleles. Here we utilize a novel analytical approach to explore these multi-allelic associations by systematically examining HLA molecules for similarities in peptide binding specificities and binding pocket structure. We demonstrate that primary predisposition to cutaneous NVP HSR, seen across ancestral groups, can be attributed to a cluster of HLA-C alleles sharing a common binding groove F pocket with HLA-C*04:01. An independent association with a group of class II alleles which share the HLA-DRB1-P4 pocket is also observed. In contrast, NVP HSR protection is afforded by a cluster of HLA-B alleles defined by a characteristic peptide binding groove B pocket. The results suggest drug-specific interactions within the antigen binding cleft can be shared across HLA molecules with similar binding pockets. We thereby provide an explanation for multiple HLA associations with cutaneous NVP HSR and advance insight into its pathogenic mechanisms.

Supernatant from Hepatocyte Cultures with Drugs That Cause Idiosyncratic Liver Injury Activates Macrophage Inflammasomes.

There is increasing evidence that most idiosyncratic drug-induced liver injury (IDILI) is immune mediated, and in most cases, reactive metabolites appear to be responsible for the induction of this immune response. Reactive metabolites can cause cell damage with the release of damage-associated molecular patterns (DAMPs), which is thought to be involved in immune activation. Presumably, the reason that the liver is a common target of idiosyncratic drug reactions is because it is the major site of drug metabolism and reactive metabolite formation. Inflammasomes can be activated by DAMPs, and this may be a common mechanism by which DAMPs initiate an immune response. In this study, we tested the ability of drugs to induce the release of DAMPs that activate inflammasomes. The drugs tested were amodiaquine and nevirapine; both are associated with significant incidences of severe IDILI. The hepatocytes were a human hepatocarcinoma functional liver cell-4 (FLC-4) cell line. For the detection of inflammasome activation, we used the human macrophage cell line, THP-1 cells. We found that the supernatant from the incubation of both drugs with FLC-4 cells for 7 days led to increased caspase-1 activity and production of IL-1ß by THP-1 cells. However, amodiaquine alone also directly activated THP-1 cells. This is presumably because the myeloperoxidase in THP-1 cells can bioactivate amodiaquine to a reactive metabolite. In contrast, nevirapine requires cytochromes P450 for reactive metabolite formation and therefore required incubation with hepatocytes. These results support the hypothesis that reactive metabolites of drugs can cause the release of DAMPs, which in turn can activate inflammasomes. Inflammasome activation may be an important step in the activation of the immune system by drugs, which in some patients can lead to IDILI. Our in vitro model is simple and convenient for evaluating inflammasome activation, and this may be a method to screen drugs for IDILI risk.

An update on HLA alleles associated with adverse drug reactions.

Adverse drug reactions (ADRs) are considered as an important cause of morbidity and mortality. The hypersensitivity reactions are immune-mediated ADRs, which are dose-independent, unpredictable and have been associated with several HLA alleles. The present review aimed to describe HLA alleles that have been associated with different ADRs in populations worldwide, the recommendations of regulatory agencies and pharmacoeconomic information and databases for the study of HLA alleles in pharmacogenetics. A systematic search was performed in June 2016 of articles relevant to this issue in indexed journals and in scientific databases (PubMed and PharmGKB). The information of 95 association studies found was summarized. Several HLA alleles and haplotypes have been associated with ADRs induced mainly by carbamazepine, allopurinol, abacavir and nevirapine, among other drugs. Years with the highest numbers of publications were 2013 and 2014. The majority of the reports have been performed on Asians and Caucasians, and carbamazepine was the most studied ADR drug inducer. Two HLA alleles' databases are described, as well as the recommendations of the U.S. Food and Drug Administration, the European Medicine Agency and the Clinical Pharmacogenetics Implementation Consortium. Pharmacoeconomic studies on this issue are also mentioned. The strongest associations remain for HLA-B*58:01, HLA-B*57:01, HLA-B*15:02 and HLA-A*31:01 but only in certain populations; therefore, studies on different ethnic groups would be useful. Due to the improvement of drug therapy and the economic benefit that HLA screening represents, investigations on HLA alleles associated with ADR should continue.

Nevirapine Pharmacokinetics and Safety in Neonates Receiving Combination Antiretroviral Therapy for Prevention of Vertical HIV Transmission.

BACKGROUND: Nevirapine (NVP)-based combination antiretroviral therapy is routinely prescribed to infants deemed at high risk of vertical HIV infection in our centers. We evaluated NVP pharmacokinetics and safety of this regimen. METHODS: Neonates were recruited prospectively between September 2012 and April 2015 or enrolled retrospectively if treated similarly before prospective study initiation. NVP was dosed at 150 mg/m daily for 14 days, then twice daily for 14 days. NVP levels were drawn at weeks 1, 2, and 4 [target trough (NVP-T): 3-8 mg/L]. RESULTS: Thirty-three neonates were included (23 prospectively). Median gestational age (GA) and birth weight were 38 weeks (32-41 weeks) and 2.9 kg (1.5-4.2 kg), respectively. Median NVP-Ts were 8.2 mg/L (1.6-25.1 mg/L), 3.5 mg/L (1.6-6.8 mg/L), and 4.3 mg/L (0.1-19.9 mg/L) at weeks 1, 2, and 4, respectively. The proportions with therapeutic NVP-T were 42%, 61%, and 73% at these same timepoints. Median apparent oral clearance (CL/F) increased from 0.05 L·kg·h (0.01-0.50 L·kg·h) at week 2 to 0.18 L·kg·h (0.01-0.78 L·kg·h) at week 4. Increased drug exposure [area under the curve (AUCτ)] correlated with younger GA (r = 0.459, P = 0.032) and lower birth weight (r = 0.542, P = 0.009). The most common adverse events potentially attributable to combination antiretroviral therapy were transient asymptomatic hyperlactatemia (26%), anemia (24.7%), and neutropenia (22.1%). CONCLUSIONS: Treatment dose NVP was generally well-tolerated and associated with normalization of trough levels over time in most cases without dose adjustment. Lower empiric dosing is recommended for infants <34 weeks of GA. Routine therapeutic drug monitoring may not be required for infants ≥34 weeks of GA.

Adverse drug reactions associated with antiretroviral therapy in South Africa.

South Africa has one of the highest prevalences of HIV and AIDS in the world. HIV/AIDS patients face countless challenges, one of which is the risk of adverse drug reactions (ADRs). This study aimed to describe the ADRs reported in South Africa with reference to the type of ADRs, antiretrovirals (ARVs) implicated, seriousness of the ADRs and patient demographics associated with specific ADRs. A retrospective quantitative study was carried out using ADR reports submitted to the National Department of Health (NDoH) from 1 January 2010 to 31 December 2014. A descriptive and inferential analysis was carried out to determine the strength of the relationships between different variables. A total of 2 489 reports were analysed. This study found evidence of ADRs among patients on regimens based on stavudine (n = 1 256, 50.46%), efavirenz (n = 572, 22.98%), zidovudine (n = 209, 8.40%), tenofovir (n = 203, 8.16%) and nevirapine (n = 153, 6.15%). The 10 most common ADRs reported with the use of ARVs were peripheral neuropathy (n = 472, 19%), lipodystrophy (n = 471, 18.9%), serious skin reactions (n = 266, 10.7%), gynaecomastia (n = 219, 8.8%), renal failure (n = 140, 5.6%), dizziness (n = 133, 5.3%), hyperlactatemia (n = 118, 4.7%), psychosis/hallucinations (n = 47, 1.9%), sleep disturbances (n = 44, 1.8%) and vomiting (n = 44, 1.8%). Female patients were more likely to experience peripheral neuropathy, lipodystrophy, skin rash, anaemia and hyperlactatemia, while male patients were more prone to experience gynaecomastia and peripheral neuropathy. In addition, patients aged 30-44 years reported the most ADRs. Most reactions resulted from the use of stavudine, efavirenz, zidovudine, nevirapine and tenofovir in the population groups identified in this study.

A Single-Nucleotide Polymorphism in ABCC4 Is Associated with Tenofovir-Related Beta2-Microglobulinuria in Thai Patients with HIV-1 Infection.

BACKGROUND: In Thailand, the combined generic anti-retroviral drug stavudine/lamivudine/nevirapine (d4T/3TC/NVP) has been used to treat human immunodeficiency virus (HIV)-infected individuals since 2001. Due to relatively frequent adverse effects, d4T gradually has been replaced with tenofovir disoproxil fumarate (TDF). Although the frequency of adverse drug effects with TDF is lower than that with d4T, TDF is known to induce kidney dysfunction, especially in the proximal tubules. It has been reported that renal tubular transporters, including members of the multi-drug resistant (MDR) protein family, are implicated in tenofovir extrusion and may, therefore, confer susceptibility to TDF-induced kidney tubular dysfunction (KTD). We have explored the association between KTD and polymorphisms in genes that encode adenosine triphosphate-binding cassette (ABC)-type MDRs. METHODS: HIV-infected patients receiving TDF-containing antiretroviral regimens for at least one year were enrolled in the study. The levels of beta2-microglobulin in urine and creatinine (Cr) were measured. Three single-nucleotide polymorphisms, ABCC2 C-24T (rs717620), ABCC2 G1429A (rs2273697), and ABCC4 T4976C (rs1059751), were analyzed using TaqMan SNP genotyping assays. RESULTS: A total of 273 HIV-infected patients were recruited. The median number of years of TDF treatment was 5.04 with interquartile range (IQR) of 3.9-6.7. Despite the length of treatment with TDF, 98.5% patients maintained an estimated glomerular filtration rate (eGFR) of >60 mL/min as calculated by the CKD-EPI formula. Fifty-four patients (19.8%) showed beta2-microglobulinuria (median 2636 µg/g Cr with IQR of 1519-13197 µg/g Cr). The allele frequency of ABCC4 T4976C among those 54 patients was 0.602, compared to 0.475 among the 219 remaining patients (p = 0.018). CONCLUSIONS: Approximately 20% of HIV-infected patients receiving TDF showed beta2-microglobulinuria. The C allele at position 4976 of the ABCC4 gene was associated with beta2-microglobulinuria in this population. This polymorphism may help to identify patients at greater risk for developing TDF-associated KTD.

A pharmacogenetics study in Mozambican patients treated with nevirapine: full resequencing of TRAF3IP2 gene shows a novel association with SJS/TEN susceptibility.

Steven-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe adverse drug reactions, characterized by extensive epidermal detachment and erosions of mucous membrane. SJS/TEN is one of the most serious adverse reactions to Nevirapine (NVP) treatment, commonly used in developing countries as first-line treatment of human immunodeficiency virus infection. In the last years TRAF3IP2 gene variants had been described as associated with susceptibility to several diseases such as psoriasis and psoriatic arthritis. We hypothesized that this gene, involved in immune response and in NF-κB activation, could also be implicated in the SJS/TEN susceptibility. We performed a full resequencing of TRAF3IP2 gene in a population of patients treated with NVP. Twenty-seven patients with NVP-induced SJS/TEN and 78 controls, all from Mozambique, were enrolled. We identified eight exonic and three intronic already described variants. The case/control association analysis highlighted an association between the rs76228616 SNP in exon 2 and the SJS/TEN susceptibility. In particular, the variant allele (C) resulted significantly associated with a higher risk to develop SJS/TEN (p = 0.012 and OR = 3.65 (95% CI 1.33-10.01)). A multivariate analysis by logistic regression confirmed its significant contribution (p = 0.027, OR = 4.39 (95% CI 1.19-16.23)). In conclusion, our study suggests that a variant in TRAF3IP2 gene could be involved in susceptibility to SJS/TEN.

Pharmacogenetic markers of severe cutaneous adverse drug reactions.

Different responses, in terms both of efficacy and toxicity, are commonly observed for any drug administered to apparently homogeneous groups of patients. It is estimated that adverse drug reactions (ADRs) cause 3-6% of all hospitalizations, accounting for 5% to 9% of hospital admission costs. The skin is often involved in ADRs and although most cutaneous ADRs have a favorable course, they may present as severe adverse cutaneous drug reactions (SCARs), such as Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (also referred to as drug-induced hypersensitivity syndrome), and acute generalized exanthematous pustulosis. SCARs are associated with significant mortality and require prompt diagnosis and adequate treatment. Pharmacogenetics studies individual variants in the DNA sequence associated with drug efficacy and toxicity, allowing prescription of a drug to patients expected to benefit from it, and excluding from treatment those who are at risk of developing ADRs. Pharmacogenetics already achieved several important results in the prevention of SCARs, and pharmacogenetic testing is now recommended by regulatory agencies before administration of abacavir and carbamazepine, leading to reduced incidence of SCARs. In this review, the pharmacogenetic associations of SCARs that have been validated in independent, case-control association studies will be presented. By familiarizing with principles of pharmacogenetics, dermatologists should be able to correlate specific cutaneous ADR phenotypes to the underlying genotype, thus contributing to better drug safety and facilitating drug discovery, development and approval.

Genotyping for severe drug hypersensitivity.

Over the past decade, there have been significant advances in our understanding of the immunopathogenesis and pharmacogenomics of severe immunologically-mediated adverse drug reactions. Such T-cell-mediated adverse drug reactions such as Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), drug-induced liver disease (DILI) and other drug hypersensitivity syndromes have more recently been shown to be mediated through interactions with various class I and II HLA alleles. Key examples have included the associations of HLA-B*15:02 and carbamazepine induced SJS/TEN in Southeast Asian populations and HLA-B*57:01 and abacavir hypersensitivity. HLA-B*57:01 screening to prevent abacavir hypersensitivity exemplifies a successful translational roadmap from pharmacogenomic discovery through to widespread clinical implementation. Ultimately, our increased understanding of the interaction between drugs and the MHC could be used to inform drug design and drive pre-clinical toxicity programs to improve drug safety.

Efficacy and safety of an extended nevirapine regimen in infants of breastfeeding mothers with HIV-1 infection for prevention of HIV-1 transmission (HPTN 046): 18-month results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: HPTN 046 compared the efficacy and safety of infant nevirapine (NVP) among HIV-exposed breastfed infants randomized at 6 weeks to 6 months to t NVP or placebo to prevent postnatal infection: we report final 18-month outcomes. METHODS: Randomized, placebo-controlled trial in 4 African countries. Infant diagnostic HIV testing was performed regularly from birth through 18 months. Kaplan-Meier analysis was used to assess 18-month cumulative infant HIV infection, HIV infection/or death, and mortality rates. RESULTS: Between 6 weeks and 6 months, postnatal HIV infection rates were significantly lower among infants receiving daily NVP from 6 weeks to 6 months 1.1% [95% confidence interval (CI): 0.2% to 1.8%], compared with placebo 2.4% (95% CI: 1.3% to 2.6%), P = 0.049, but not significantly lower thereafter. Eighteen-month postnatal infection rates were low: 2.2% (95% CI: 1.1% to 3.3%) versus 3.1% (95% CI: 1.9% to 4.4%), respectively, P = 0.28. Mortality and HIV infection/death did not differ between arms at any age. Infants of women receiving antiretroviral therapy (ART) for their own health had the lowest 18-month postnatal infection rates (0.5%, 95% CI: 0.0% to 1.1%). However, HIV infection/death rates at 18 months were not significantly different for infants of mothers on ART (3.7%, 95% CI: 1.9% to 5.5%), and infants of mothers with CD4 counts of ≥ 350 cells per cubic millimeter not receiving ART (4.8%, 95% CI: 2.7% to 6.8%; P = 0.46). There were no differences in adverse events between study arms. CONCLUSIONS: This trial demonstrated early but not late differences in postnatal HIV transmission among infants randomized at age 6 weeks to extended NVP or placebo, underscoring the importance of continued prophylaxis throughout breastfeeding.