Multiplicity of solvent environments in lipid bilayer revealed by DAS deconvolution of twin probes: Comparative method of Laurdan and Prodan

Laurdan and Prodan were designed for the evaluation of the surrounding hydration state. When inserted into lipid bilayer systems, both probes are located at different positions and their fluorescence properties are drastically varied, depending on their surrounding environment. In this study, a novel method using the above fluorescence probes was proposed on the basis of fluorescence lifetime (τ) and emission peak (λ), called as τ vs. λ plot, determined by global analysis of their multiple fluorescence decays and deconvolution of these decay-associated spectra. According to the evaluation of τ vs. λ plot, the existence of multiple fluorescence components in the membrane was revealed. In addition, their fluorescence distribution properties, described on τ vs. λ plot, of each probe tended to correspond to the phase state and vertical direction of the lipid membrane. To assess the contribution of environmental effect to each distribution, we defined the region in the τ vs. λ plot, which was modeled from a series of solvent mixtures (hexane, acetone, ethanol and water) to emulate the complex environment in the 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bilayer system. The distributions of fluorescence components of Laurdan and Prodan in lipid membranes were classified into each solvent species, and Prodan partition into bulk water was distinguished. The sensitivity of Prodan to the phase pretransition of the 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bilayer system was also observed in increasing the temperature. Noticeably, most of the fluorescence components was assigned to the solvent model, except for a single component that has longer lifetime and shorter emission wavelength. This component was dominant in solid-ordered phase; hence, it is assumed to be a specific component in lipid membranes that cannot be represented by solvents. Although these are still qualitative analytical methods, the unique approach proposed in this study provides novel insights into the multi-focal property of the membrane.

Influence of DNP Polarizing Agents on Biochemical Processes: TEMPOL in Transient Ischemic Stroke

Hyperpolarization of 13C by dissolution dynamic nuclear polarization (dDNP) boosts the sensitivity of magnetic resonance spectroscopy (MRS), making possible the monitoring in vivo and in real time of the biochemical reactions of exogenously infused 13C-labeled metabolic tracers. The preparation of a hyperpolarized substrate requires the use of free radicals as polarizing agents. Although added at very low doses, these radicals are not biologically inert. Here, we demonstrate that the presence of the nitroxyl radical TEMPOL influences significantly the cerebral metabolic readouts of a hyperpolarized [1-13C] lactate bolus injection in a mouse model of ischemic stroke with reperfusion. Thus, the choice of the polarizing agent in the design of dDNP hyperpolarized MRS experiments is of great importance and should be taken into account to prevent or to consider significant effects that could act as confounding factors.

Nitrogen-15 dynamic nuclear polarization of nicotinamide derivatives in biocompatible solutions

Dissolution dynamic nuclear polarization (dDNP) increases the sensitivity of magnetic resonance imaging by more than 10,000 times, enabling in vivo metabolic imaging to be performed noninvasively in real time. Here, we are developing a group of dDNP polarized tracers based on nicotinamide (NAM). We synthesized 1-15N-NAM and 1-15N nicotinic acid and hyperpolarized them with dDNP, reaching (13.0 ± 1.9)% 15N polarization. We found that the lifetime of hyperpolarized 1-15N-NAM is strongly field- and pH-dependent, with T1 being as long as 41 s at a pH of 12 and 1 T while as short as a few seconds at neutral pH and fields below 1 T. The remarkably short 1-15N lifetime at low magnetic fields and neutral pH drove us to establish a unique pH neutralization procedure. Using 15N dDNP and an inexpensive rodent imaging probe designed in-house, we acquired a 15N MRI of 1-15N-NAM (previously hyperpolarized for more than an hour) in less than 1 s.

Experimental, Spectroscopic, and Computational Insights into the Reactivity of "Methanal" with 2-Naphthylamines

The reactions of 2-naphthylamine and methyl 6-amino-2-naphthoate with formalin and paraformaldehyde were studied experimentally, spectrally, and by quantum chemical calculations. It was found that neither the corresponding aminals nor imines were formed under the described conditions but could be prepared and spectrally characterized at least in situ under modified conditions. Several of the previously undescribed intermediates and by-products were isolated or at least spectrally characterized. First principle density functional theory (DFT) calculations were performed to shed light on the key aspects of the thermochemistry of decomposition and further condensation of the corresponding aminals and imines. The calculations also revealed that the electrophilicity of methanal was significantly greater than that of ordinary oxo-compounds, except for perfluorinated ones. In summary, methanal was not behaving as the simplest aldehyde but as a very electron-deficient oxo-compound.

N-acetyltransferase 2 acetylator genotype-dependent N-acetylation and toxicity of the arylamine carcinogen β-naphthylamine in cryopreserved human hepatocytes

We used cryopreserved human hepatocytes that express rapid, intermediate, and slow acetylator N-acetyltransferase 2 (NAT2) genotypes to measure the N-acetylation of β-naphthylamine (BNA) which is one of the aromatic amines found in cigarette smoke including E-cigarettes. We investigated the role of NAT2 genetic polymorphism in genotoxicity and oxidative stress induced by BNA. In vitro BNA NAT2 activities in rapid acetylators was 1.6 and 3.5-fold higher than intermediate (p < 0.01) and slow acetylators (p < 0.0001). BNA N-acetylation in situ was 3 to 4- fold higher in rapid acetylators than slow acetylators, following incubation with 10 and 100 µM BNA (p < 0.01). DNA damage was two to threefold higher in the rapid versus slow acetylators (p < 0.0001) and 2.5-fold higher in intermediate versus slow acetylators following BNA treatment at 100 and 1000 μM, ROS/RNS level was the highest in rapid acetylators followed by intermediate and then slow acetylators (p < 0.0001). Our findings show that the N-acetylation of BNA is NAT2 genotype dependent in cryopreserved human hepatocytes and our data further document an important role for NAT2 genetic polymorphism in modifying BNA-induced genotoxicity and oxidative damage.

Differences in β-naphthylamine metabolism and toxicity in Chinese hamster ovary cell lines transfected with human CYP1A2 and NAT2*4, NAT2*5B or NAT2*7B N-acetyltransferase 2 haplotypes

β-naphthylamine (BNA) is an important aromatic amine carcinogen. Current exposures derive primarily from cigarette smoking including e-cigarettes. Occupational and environmental exposure to BNA is associated with urinary bladder cancer which is the fourth most frequent cancer in the United States. N-acetyltransferase 2 (NAT2) is an important metabolizing enzyme for aromatic amines. Previous studies investigated mutagenicity and genotoxicity of BNA in bacteria and in rabbit or rat hepatocytes. However, the effects of human NAT2 genetic polymorphism on N-acetylation and genotoxicity induced by BNA still need to be clarified. We used nucleotide excision repair-deficient Chinese hamster ovary (CHO) cells that were stably transfected with human CYP1A2 and NAT2 alleles: NAT2*4 (reference allele), NAT2*5B (variant slow acetylator allele common in Europe) or NAT2*7B (variant slow acetylator allele common in Asia). BNA N-acetylation was measured both in vitro and in situ via high-performance liquid chromatography (HPLC). Hypoxanthine phosphoribosyl transferase (HPRT) mutations, double-strand DNA breaks, and reactive oxygen species (ROS) were measured as indices of toxicity. NAT2*4 cells showed significantly higher BNA N-acetylation rates followed by NAT2*7B and NAT2*5B. BNA caused concentration-dependent increases in DNA damage and ROS levels. NAT2*7B showed significantly higher levels of HPRT mutants, DNA damage and ROS than NAT2*5B (p < 0.001, p < 0.0001, p < 0.0001 respectively) although both are slow alleles. Our findings suggest that BNA N-acetylation and toxicity are modified by NAT2 polymorphism. Furthermore, they confirm heterogeneity among slow acetylator alleles for BNA metabolism and toxicity supporting differential risk for individuals carrying NAT2*7B allele.

Hexavalent chromium increases the metabolism and genotoxicity of aromatic amine carcinogens 4-aminobiphenyl and β-naphthylamine in immortalized human lung epithelial cells

Humans are exposed to carcinogenic chemicals via occupational and environmental exposures. Common chemicals of concern that can occur in exposures together are aromatic amines (e.g., 4-aminobiphenyl [4-ABP] and β-naphthylamine [BNA]) and hexavalent chromium (Cr[VI]). Arylamine N-acetyltransferases 1 and 2 (NAT1 and NAT2) are key to the metabolism of aromatic amines and their genotoxicity. The effects of Cr(VI) on the metabolism of aromatic amines remains unknown as well as how it may affect their ensuing toxicity. The objective of the research presented here is to investigate the effects of Cr(VI) on the metabolism and genotoxicity of 4-ABP and BNA in immortalized human lung epithelial cells (BEP2D) expressing NAT1 and NAT2. Exposure to Cr(VI) for 48 h increased NAT1 activity (linear regression analysis: P < 0.0001) as measured by N-acetylation of para-aminobenzoic acid (PABA) in BEP2D cells but not NAT2 N-acetylation of sulfamethazine, which are prototypic NAT1 and NAT2 substrates respectively. Cr(VI) also increased the N-acetylation of 4-ABP and BNA. In BEP2D cells the N-acetylation of 4-ABP (1-3 μM) exhibited a dose-dependent increase (linear regression analysis: P < 0.05) following co-incubation with 0-3 μM Cr(VI). In BEP2D cells, incubation with Cr(VI) caused dose-dependent increases (linear regression analysis: P < 0.01) in expression of CYP1A1 protein and catalytic activity. For genotoxicity, BEP2D cells were exposed to 4-ABP or BNA with/without Cr(VI) for 48 h. We observed dose-dependent increases (linear regression analysis: P < 0.01) in phospho-γH2AX protein expression for combined treatment of 4-ABP or BNA with Cr(VI). Further using a CYP1A1 inhibitor (α-naphthoflavone) and NAT1 siRNA, we found that CYP1A1 inhibition did not reduce the increased N-acetylation or genotoxicity of BNA by Cr(VI), while NAT1 inhibition did reduce increases in BNA N-acetylation and genotoxicity by Cr(VI). We conclude that during co-exposure of aromatic amines and Cr(VI) in human lung cells, Cr(VI) increased NAT1 activity contributing to increased 4-ABP and BNA genotoxicity.

Hydrogen Cyanide and Aromatic Amine Yields in the Mainstream Smoke of 60 Little Cigars

Mainstream smoke yields of hydrogen cyanide (HCN) and three aromatic amines, 1-aminonaphthalene, 2-aminonaphthalene, and 4-aminobiphenyl, from 60 little cigar brands currently on the US market were measured for both International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimens. The smoke yields are compared with those from 50 cigarette products measured by Counts et al. of Philip Morris USA (PMUSA) in 2005 [Counts et al. Regul. Toxicol. Pharmacol. 2005 41, 185-227] and 50 cigarette products measured by the Centers for Disease Control and Prevention (CDC) in cooperation with the Food and Drug Administration (FDA) in 2012 [Tynan et al. Consumption of Cigarettes and Combustible Tobacco: United States, 2000-2011. In Morbidity and Mortality Weekly Report; Centers for Disease Control and Prevention, 2012; 565-580]. For the little cigars, the average HCN yield with the ISO smoking regimen is 335 μg/cigar (range: 77-809 μg/cigar), which is 332% higher than the average of 50 PMUSA 2005 cigarettes and 243% higher than the average of 50 CDC/FDA 2012 cigarettes. For the CI smoking regimen, the average HCN yield is 619 μg/cigar (range: 464-1045 μg/cigar), which is 70.5% higher than the average of 50 PMUSA 2005 cigarettes and 69% higher than the average of the 50 CDC/FDA 2012 cigarettes. For aromatic amines, the average ISO smoking regimen smoke yields are 36.6 ng/cigar (range: 15.9-70.6 ng/cigar) for 1-aminonaphthalene, 24.6 ng/cigar (range: 12.3-36.7 ng/cigar) for 2-aminonaphthalene, and 5.6 ng/cigar (range: 2.3-17.2 ng/cigar) for 4-aminobiphenyl. The average ISO yields of aromatic amines from little cigars are 141% to 210% higher compared to the average yields of 50 PMUSA cigarettes. The average CI smoke regimen yields are 73.0 ng/cigar (range: 32.1-112.2 ng/cigar) for 1-aminonaphthalene, 45.2 ng/cigar (range: 24.6-74.8 ng/cigar) for 2-aminonaphthalene, and 12.7 ng/cigar (range: 5.5-37.5 ng/cigar) for 4-aminobiphenyl. The average CI aromatic amine yields are 143% to 220% higher compared to the average yields of 50 PMUSA cigarettes, almost identical to the relative yields under the ISO smoking regimen. Both HCN and aromatic amine yields are 1.5× to 3× higher for the tested little cigars than for the conventional cigarettes; however, there are notable differences in the relationships of these yields to certain product characteristics, such as weight, ventilation, and tobacco type. The higher smoke yields of these compounds from little cigars indicates that cigar smokers may be at risk of a higher exposure to HCN and aromatic amines on a per stick basis and thus increased health concerns.

Drug-Drug Interactions With Cyclosporine in the Anti-Hepatitis C Viral PrOD Combination Regimen of Paritaprevir/Ritonavir-Ombitasvir and Dasabuvir in Organ Transplant Recipients With Severe Hepatic Fibrosis or Cirrhosis

BACKGROUND

The clinical guidelines suggest that the dosing of cyclosporine (CsA), during combination therapy with paritaprevir/ritonavir-ombitasvir and dasabuvir (PrOD), would be only one-fifth of the pre-PrOD total daily dose to be administered once daily. However, this dosing may not be applicable to all patients depending on their clinical condition. This study focuses on the pharmacokinetic dynamics of PrOD with CsA in Asian organ transplant recipients with severe liver fibrosis or cirrhosis who undergo concurrent treatment with PrOD treatment and CsA. The efficacy and safety of PrOD treatment was also evaluated.

METHODS

Data from 7 patients obtained between January 2017 and September 2017 were retrospectively analyzed. Determinations of the blood concentrations of CsA were made, whether used as a single treatment or in combination therapy with PrOD.

RESULTS

The combination regimen compared with CsA administered alone resulted in a 4.53-fold and 5.52-fold increase in the area under the concentration-time curve from time 0-12 hours (AUC0-12 h) of CsA on days 1 and 15, respectively. In addition, the maximal concentration, time to maximum concentration, and terminal phase elimination half-life (t1/2) of CsA were increased during the combined treatment of PrOD and CsA. The authors proposed reducing the CsA dosage during PrOD treatment to one-seventh of that of the pre-PrOD treatment of the total daily dose to maintain target CsA levels. All patients achieved sustained virologic responses at week 12. There were no episodes of serious adverse events or graft rejections observed.

CONCLUSIONS

Although the combination with PrOD significantly affects the pharmacokinetics of CsA, it is effective and safe with regular monitoring of the CsA blood concentrations and appropriate CsA dose adjustment.

Efficacy and Safety of Ombitasvir/Paritaprevir/ Ritonavir + Dasabuvir ± Ribavirin Combinations in Patients with Genotype 1 Hepatitis C and Inherited Bleeding Disorders

BACKGROUND

Hepatitis C is one of the leading causes of death in patients with inherited bleeding disorders. Currently, direct-acting antiviral drugs used for the treatment of hepatitis C have become an effective and a reliable option for people with inherited bleeding disorders. The aim of this study is to report the efficacy and safety of ombitasvir + paritaprevir/ritonavir and dasabuvir combination in the treatment of hepatitis C in patients with inherited bleeding disorders.

METHODS

In this retrospective study, we evaluated the efficacy and safety of the combination of ombitasvir + paritaprevir/ritonavir and dasabuvir in 10 adult patients with hemophilia A, 4 patients with hemophilia B, and 1 patient with von Willebrand disease who were infected with hepatitis C genotype 1.

RESULTS

Five patients had genotype 1a and 10 patients had genotype 1b chronic hepatitis C. One patient had Child A cirrhosis, 14 patients had chronic hepatitis C without cirrhosis. Hepatitis C virus ribonucleic acid was negative in all patients at week 4 and at the end of the treatment. Sustained virologic response was obtained in all patients. Serious side effects were detected in 3 patients, which were intra- muscular bleeding, erosive gastritis-related gastrointestinal bleeding, and pneumonia.

CONCLUSION

Ombitasvir + paritaprevir combined with ritonavir and dasabuvir ± ribavirin is an effective treatment for patients infected with genotype 1 hepatitis C who have coagulation disorders. Tolerance and side effects are similar to other treatment options.

Ombitasvir/paritaprevir/ritonavir and dasabuvir±ribavirin for chronic HCV infection in US veterans with psychiatric disorders

Hepatitis C virus (HCV) infections are more common among US veterans receiving care through Veterans Affairs (VA) Medical Centers than among the general population. Historically, HCV therapies had lower efficacy rates in VA patients, possibly due to common comorbidities such as psychiatric disorders and substance abuse. The direct-acting antivirals ombitasvir/paritaprevir/ritonavir and dasabuvir (OBV/PTV/r+DSV)±ribavirin (RBV) are approved in the US for HCV genotype 1 (GT1)-infected adults with or without cirrhosis. This study prospectively evaluated the safety and efficacy of OBV/PTV/r+DSV±RBV in VA patients with HCV GT1 infection. TOPAZ-VA was a phase 3b, open-label trial. Adult US veterans with HCV GT1 infection, without cirrhosis or with compensated cirrhosis, were eligible for enrollment. Patients with GT1a infection received OBV/PTV/r +DSV+RBV for 12 weeks or 24 weeks (for those with cirrhosis); GT1b-infected patients without cirrhosis received OBV/PTV/r +DSV for 12 weeks; those with cirrhosis received OBV/PTV/r +DSV with RBV. The primary endpoint was sustained virologic response at posttreatment week 12 (SVR12); safety was also assessed. Ninety-nine patients were enrolled at 10 sites from May through November 2015. The majority were male (96%), white (60%), and with GT1a infection (68%); 49% reported ongoing psychiatric disorders. Overall, 94% (93/99) achieved SVR12; three patients had a virologic failure. The most common AEs were fatigue (28%), headache (20%), and nausea (15%); six patients discontinued treatment due to AEs. In US veterans with HCV GT1 infection, OBV/PTV/r +DSV±RBV yielded a 94% overall SVR12 rate and was well tolerated. The presence of psychiatric disorders and/or injection drug use did not impact efficacy.

Raltegravir pharmacokinetics before and during treatment with ombitasvir, paritaprevir/ritonavir plus dasabuvir in adults with human immunodeficiency virus-1 and hepatitis C virus coinfection: AIDS Clinical Trials Group sub-study A5334s

AIMS

AIDS Clinical Trials Group study A5334s evaluated the pharmacokinetics of raltegravir before and during combined administration of ombitasvir, paritaprevir/ritonavir, plus dasabuvir (OBV/PTV/r + DSV) and weight-based ribavirin in human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfected adults. The pharmacokinetics of OBV/PTV/r + DSV during raltegravir coadministration were also characterized.

METHODS

Adults living with HIV/HCV coinfection receiving steady-state raltegravir (400 mg twice daily) with 2 nucleos(t)ide analogues were enrolled. Pharmacokinetics of raltegravir were assessed prior to HCV therapy, and 4 weeks later following initiation of OBV/PTV/r (25/150/100 mg) once daily + DSV (250 mg) twice daily. Geometric mean ratios (GMRs) and 90% confidence intervals (CIs) were used to compare the following: raltegravir pharmacokinetics with HCV therapy (week 4) vs before HCV therapy (week 0); OBV/PTV/r and DSV pharmacokinetics vs historical healthy controls; raltegravir pharmacokinetics at week 0 vs historical control adults living with HIV.

RESULTS

Eight of 11 participants had decreased raltegravir exposures after initiation of HCV therapy. The GMRs (90% CI) for maximum concentration and area under the concentration-time curve of raltegravir with vs without HCV therapy were 0.68 (0.38-1.19) and 0.82 (0.58-1.17), respectively. Comparing OBV/PTV/r pharmacokinetics in healthy controls, A5334s study participants demonstrated generally lower maximum concentration and area under the concentration-time curve values by 41-82% and 4-73%, respectively. Raltegravir exposures tended to be higher in A5334s study participants compared to adults living with HIV.

CONCLUSIONS

The majority of participants' plasma raltegravir exposures were lower after initiation of HCV therapy in coinfected adults; however, confidence intervals were wide.

Real-world evidence of the effectiveness of ombitasvir-paritaprevir/r ± dasabuvir ± ribavirin in patients monoinfected with chronic hepatitis C or coinfected with human immunodeficiency virus-1 in Spain

Aim

We describe the effectiveness and safety of the interferon-free regimen ombitasvir/paritaprevir/ritonavir plus dasabuvir with or without ribavirin (OBV/PTV/r ± DSV ± RBV) in a nationwide representative sample of the hepatitis C virus (HCV) monoinfected and human immunodeficiency virus-1/hepatitis C virus (HIV/HCV) coinfected population in Spain.

Material and methods

Data were collected from patients infected with HCV genotypes 1 or 4, with or without HIV-1 coinfection, treated with OBV/PTV/r ± DSV ± RBV at 61 Spanish sites within the initial implementation year of the first government-driven “National HCV plan.” Effectiveness was assessed by sustained virologic response at post-treatment week 12 (SVR12) and compared between monoinfected and coinfected patients using a non-inferiority margin of 5% and a 90% confidence interval (CI). Sociodemographic and clinical characteristics or patients and adverse events (AEs) were also recorded.

Results

Overall, 2,408 patients were included in the intention-to-treat analysis: 386 (16%) were patients with HIV/HCV. Patient selection reflected the real distribution of patients treated in each participating region in Spain. From the total population, 96.6% (95% CI, 95.8–97.3%) achieved SVR12. Noninferiority of SVR12 in coinfected patients was met, with a difference between monoinfected and coinfected patients of −2.2% (90% CI, −4.5% - 0.2%). Only genotype 4 was associated with non-response to OBV/PTV/r ± DSV ± RBV treatment (p<0.001) in the multivariate analysis. Overall, 286 patients (11.9%) presented AEs potentially related to OBV/PTV/r ± DSV, whereas 347 (29.0%) presented AEs potentially related to ribavirin and 61 (5.1%) interrupted ribavirin.

Conclusions

Our results confirm that OBV/PTV/r ± DSV ± RBV is effective and generally well tolerated in a representative sample of the HCV monoinfected and HCV/HIV coinfected population in Spain within the experience of a national strategic plan to tackle HCV.

Efficacy, Safety, and Predictors of Direct-acting antivirals in Hepatitis C Virus Patients with Heterogeneous Liver Diseases

Safety, efficacy, and predictor factors of sustained-virological-response after 24 weeks of new direct-acting antivirals were evaluated in hepatitis C virus patients with different stages of hepatic disease. 260 patients, median age 60 years, of whom 48.1% cirrhotics, 17.7% liver transplant recipients, and 45.7% naïve were treated with Sofosbuvir+Ribavirine, Sofosbuvir+Simeprevir±Ribavirine, Sofosbuvir+Daclatasvir± Ribavirine, Sofosbuvir+Ledispavir±Ribavirine, Ombitasvir/Paritaprevir/Ritonavir+Ribavirine and Ombitasvir/Paritaprevir/Ritonavir+Dasabuvir±Ribavirine. Therapy outcomes, hematochemical parameters, viral replication, genotype, and resistance-associated-mutations were analyzed retrospectively. Sustained virological response was 90.4% in the whole population, 83.2% in cirrhotics, 85% in patients with previous virological failure, 93.6% in patients >60 years, and 95.6% in liver transplant recipients. SVR24 for each drug regimen was 75% Sofosbuvir+Ribavirine, 80.4% Sofosbuvir+Simeprevir±Ribavirine, 94.3% Sofosbuvir+Daclatasvir±Ribavirine, 98.7% Sofosbuvir+Ledispavir±Ribavirine, 100% Ombitasvir/ Paritaprevir/Ritonavir+Ribavirine and Ombitasvir/Paritaprevir/Ritonavir+Dasabuvir±Ribavirine. The highest sustained virological response rates were obtained with genotype-1b (95.9%). Twenty-five patients, mostly cirrhotics or suffering from severe liver complications, manifested relapse (84%), breakthrough (12%), or non-response (4%). Mild side effects were observed in 41.1% of patients. Model-for-End-Liver- Disease score <10 and alanine aminotransferase ≤20 U/L at week 8 of therapy proved positive predictors of sustained virological response. Direct-acting antiviral therapy is efficacious and safe even in patients with advanced liver disease and/ or previous virological failure; Model-for-End-Liver-Disease <10 and alanine aminotransferase reduction during therapy were found to be reliable predicting markers of sustained-virological-response.

Effectiveness, safety/tolerability of OBV/PTV/r ± DSV in patients with HCV genotype 1 or 4 with/without HIV-1 co-infection, chronic kidney disease (CKD) stage IIIb-V and dialysis in Spanish clinical practice - Vie-KinD study

BACKGROUND AND AIMS

Limited data are available on the effectiveness and tolerability of direct-acting antivirals (DAAs) therapies in the real world for HCV-infected patients with comorbidities. This study aimed to describe the effectiveness of OBV/PTV/r ± DSV (3D/2D regimen) with or without ribavirin (RBV) in HCV or HCV/HIV co-infected patients with GT1/GT4 and CKD (IIIb-V stages), including those under hemodialysis and peritoneal dialysis in routine clinical practice in Spain in 2015.

MATERIAL AND METHODS

Non-interventional, retrospective, multicenter data collection study in 31 Spanish sites. Socio-demographic, clinical variables, study treatment characteristics, effectiveness and tolerability data were collected from medical records.

RESULTS

Data from 135 patients with a mean age (SD) of 58.3 (11.4) years were analyzed: 92.6% GT1 (81.6% GT1b and 17.6% GT1a) and 7.4% GT4, 14 (10.4%) HIV/HCV co-infected, 19.0% with fibrosis F3 and 28.1% F4 by FibroScan®, 52.6% were previously treated with pegIFN and RBV. 11.1%, 14.8% and 74.1% of patients had CKD stage IIIb, IV and V respectively. 68.9% of patients were on hemodialysis; 8.9% on peritoneal dialysis and 38.5% had history of renal transplant. A total of 125 (96.2%) of 135 patients were treated with 3D, 10 (7.4%) with 2D and 30.4% received RBV. The overall intention-to-treat (ITT) sustained virologic response at week 12 (SVR12) was 92.6% (125/135) and the overall modified-ITT (mITT) SVR12 was 99.2% (125/126). The SVR12 rates (ITT) per sub-groups were: HCV mono-infected (91.7%), HCV/HIV co-infected (100%), GT1 (92.0%), GT4 (100%), CKD stage IIIb (86.7%), stage IV (95%) and stage V (93%). Among the 10 non-SVR there was only 1 virologic failure (0.7%); 4 patients had missing data due lost to follow up (3.0%) and 5 patients discontinued 3D/2D regimen (3.7%): 4 due to severe adverse events (including 3 deaths) and 1 patient´s decision.

CONCLUSIONS

These results have shown that 3D/2D regimens are effective and tolerable in patients with advanced CKD including those in dialysis with GT 1 or 4 chronic HCV mono-infection and HIV/HCV coinfection in a real-life cohort. The overall SVR12 rates were 92.6% (ITT) and 99.2% (mITT) without clinically relevant changes in eGFR until 12 weeks post-treatment. These results are consistent with those reported in clinical trials.

Sustained virologic response to direct-acting antiviral therapy in patients with chronic hepatitis C and hepatocellular carcinoma: A systematic review and meta-analysis

BACKGROUND & AIMS

The effect of hepatocellular carcinoma (HCC) on the response to interferon-free direct-acting antiviral (DAA) therapy in patients with chronic hepatitis C (CHC) infection remains unclear. Using a systematic review and meta-analysis approach, we aimed to investigate the effect of DAA therapy on sustained virologic response (SVR) among patients with CHC and either active, inactive or no HCC.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials were searched from 1/1/2013 to 9/24/2018. The pooled SVR rates were computed using DerSimonian-Laird random-effects models.

RESULTS

We included 49 studies from 15 countries, comprised of 3,341 patients with HCC and 35,701 without HCC. Overall, the pooled SVR was lower in patients with HCC than in those without HCC (89.6%, 95% CI 86.8-92.1%, I² = 79.1% vs. 93.3%, 95% CI 91.9-94.7%, I² = 95.0%, p = 0.0012), translating to a 4.8% (95% CI 0.2-7.4%) SVR reduction by meta-regression analysis. The largest SVR reduction (18.8%) occurred in patients with active/residual HCC vs. inactive/ablated HCC (SVR 73.1% vs. 92.6%, p = 0.002). Meanwhile, patients with HCC who received a prior liver transplant had higher SVR rates than those who did not (p <0.001). Regarding specific DAA regimens, patients with HCC treated with ledipasvir/sofosbuvir had lower SVR rates than patients without HCC (92.6%, n = 884 vs. 97.8%, n = 13,141, p = 0.026), but heterogeneity was high (I² = 84.7%, p <0.001). The SVR rate was similar in patients with/without HCC who were treated with ombitasvir/paritaprevir/ritonavir ± dasabuvir (n = 101) (97.2% vs. 94.8%, p = 0.79), or daclatasvir/asunaprevir (91.7% vs. 89.8%, p = 0.66).

CONCLUSION

Overall, SVR rates were lower in patients with HCC, especially with active HCC, compared to those without HCC, though heterogeneity was high. Continued efforts are needed to aggressively screen, diagnose, and treat HCC to ensure higher CHC cure rates.

LAY SUMMARY

There are now medications (direct-acting antivirals or "DAAs") that can "cure" hepatitis C virus, but patients with hepatitis C and liver cancer may be less likely to achieve cure than those without liver cancer. However, patients with liver cancer are also more likely to have advanced liver disease and risk factors that can decrease cure rates, so better controlled studies are needed to confirm these findings.

Patient-reported symptoms during and after direct-acting antiviral therapies for chronic hepatitis C: The PROP UP study

BACKGROUND & AIMS

A comprehensive analysis of changes in symptoms and functioning during and after direct-acting antiviral (DAA) therapy for chronic hepatitis C virus (HCV) infection has not been conducted for patients treated in real-world clinical settings. Therefore, we evaluated patient-reported outcomes (PROs) in a diverse cohort of patients with HCV treated with commonly prescribed DAAs.

METHODS

PROP UP is a US multicenter observational study of 1,601 patients with HCV treated with DAAs in 2016-2017. PRO data were collected at baseline (T1), early on-treatment (T2), late on-treatment (T3) and 3-months post-treatment (T4). PRO mean change scores were calculated from baseline and a minimally important change (MIC) threshold was set at 5%. Regression analyses investigated patient and treatment characteristics independently associated with PRO changes on-treatment and post-treatment.

RESULTS

Of 1,564 patients, 55% were male, 39% non-white, 47% had cirrhosis. Sofosbuvir/ledipasvir was prescribed to 63%, sofosbuvir/velpatasvir to 21%, grazoprevir/elbasvir to 11%, and paritaprevir/ombitasvir/ritonavir + dasabuvir to 5%. During DAA therapy, mean PRO scores improved slightly in the overall cohort, but did not reach the 5% MIC threshold. Between 21-53% of patients experienced >5% improved PROs while 23-36% experienced >5% worse symptoms. Of 1,410 patients with evaluable sustained virologic response (SVR) data, 95% achieved SVR. Among those with SVR, all mean PRO scores improved, with the 5% MIC threshold met for fatigue, sleep disturbance, and functioning well-being. Regression analyses identified subgroups, defined by age 35-55, baseline mental health issues and a higher number of health comorbidities as predictors of PRO improvements.

CONCLUSIONS

In real-world clinical practices, we observed heterogeneous patient experiences during and after DAA treatment. Symptom improvements were more pronounced in younger patients, those with baseline mental health issues and multiple comorbidities.

LAY SUMMARY

Patients who received direct-acting antiviral medications for hepatitis C at several liver centers in the US did not generally experience significant changes in baseline symptoms during treatment. We observed a full range of patient experiences with some patients experiencing substantial symptom improvements, yet others experiencing less improvements and some even experiencing a worsening of symptoms. The 1,346 patients who were cured of hepatitis C experienced improvements in fatigue, sleep disturbance, and functional well-being, and trends for improved pain and depression; whereas the 64 who were not cured experienced minimal improvements. Clinicaltrial.gov: NCT02601820.

Evolutionary Pathways to Persistence of Highly Fit and Resistant Hepatitis C Virus Protease Inhibitor Escape Variants

Protease inhibitors (PIs) are important components of treatment regimens for patients with chronic hepatitis C virus (HCV) infection. However, emergence and persistence of antiviral resistance could reduce their efficacy. Thus, defining resistance determinants is highly relevant for efforts to control HCV. Here, we investigated patterns of PI resistance-associated substitutions (RASs) for the major HCV genotypes and viral determinants for persistence of key RASs. We identified protease position 156 as a RAS hotspot for genotype 1-4, but not 5 and 6, escape variants by resistance profiling using PIs grazoprevir and paritaprevir in infectious cell culture systems. However, except for genotype 3, engineered 156-RASs were not maintained. For genotypes 1 and 2, persistence of 156-RASs depended on genome-wide substitution networks, co-selected under continued PI treatment and identified by next-generation sequencing with substitution linkage and haplotype reconstruction. Persistence of A156T for genotype 1 relied on compensatory substitutions increasing replication and assembly. For genotype 2, initial selection of A156V facilitated transition to 156L, persisting without compensatory substitutions. The developed genotype 1, 2, and 3 variants with persistent 156-RASs had exceptionally high fitness and resistance to grazoprevir, paritaprevir, glecaprevir, and voxilaprevir. A156T dominated in genotype 1 glecaprevir and voxilaprevir escape variants, and pre-existing A156T facilitated genotype 1 escape from clinically relevant combination treatments with grazoprevir/elbasvir and glecaprevir/pibrentasvir. In genotype 1 infected patients with treatment failure and 156-RASs, we observed genome-wide selection of substitutions under treatment. Conclusion: Comprehensive PI resistance profiling for HCV genotypes 1-6 revealed 156-RASs as key determinants of high-level resistance across clinically relevant PIs. We obtained in vitro proof of concept for persistence of highly fit genotype 1-3 156-variants, which might pose a threat to clinically relevant combination treatments.

Efficacy and safety of ombitasvir/paritaprevir/ritonavir and dasabuvir with low-dose ribavirin in patients with chronic hepatitis C virus genotype 1a infection without cirrhosis

Patients infected with hepatitis C virus (HCV) treated with interferon-free direct-acting antivirals may still require ribavirin. However, ribavirin is associated with adverse events that can limit its use. This open-label, multicentre, Phase 3 study evaluated the safety and efficacy of ombitasvir/paritaprevir/ritonavir + dasabuvir (OBV/PTV/r + DSV) with low-dose ribavirin for 12 weeks in genotype 1a-infected patients without cirrhosis. The primary efficacy endpoint was sustained virologic response at post-treatment Week 12 (SVR12). The primary safety endpoint was haemoglobin <10 g/dL during treatment and decreased from baseline. Overall, 105 patients enrolled. The SVR12 rate was 89.5% (n/N = 94/105; 95% CI, 83.7-95.4). The study did not achieve noninferiority versus the historic SVR12 rate for OBV/PTV/r + DSV plus weight-based ribavirin. Five patients experienced virologic failure, four discontinued, and two had missing SVR12 data. Excluding nonvirologic failures, the SVR12 rate was 94.9% (n/N = 94/99). One patient met the primary safety endpoint. OBV/PTV/r + DSV plus low-dose ribavirin offers an alternative option for patients in whom full-dose ribavirin may compromise tolerability, although noninferiority to the weight-based ribavirin regimen was not met.

Real-world safety and effectiveness of ombitasvir/paritaprevir/ritonavir ± dasabuvir ± ribavirin in hepatitis C virus genotype 1- and 4-infected patients with diverse comorbidities and comedications: A pooled analysis of post-marketing observational studies from 13 countries

Ombitasvir/paritaprevir/ritonavir ± dasabuvir ± ribavirin (OBV/PTV/r ± DSV ± RBV) regimens show high efficacy and good tolerability in clinical trials for chronic hepatitis C virus (HCV) genotypes (GT) 1 or 4. To evaluate whether these results translate to clinical practice, data were pooled from observational studies across 13 countries. Treatment-naïve or -experienced patients, with or without cirrhosis, received OBV/PTV/r ± DSV ± RBV according to approved local labels and clinical practice. Sustained virologic response at post-treatment Week 12 (SVR12), adverse events (AEs) and comedication management were assessed for patients initiating treatment before 1 June 2017. The safety population included 3850 patients who received ≥1 dose of study drug. The core population (N = 3808) further excluded patients with unknown GT or cirrhosis status, or who received off-label treatment. Patients had HCV GT1a (n = 732; 19%), GT1b (n = 2619; 69%) or GT4 (n = 457; 12%). In 3546 patients with sufficient follow-up data at post-treatment Week 12, the SVR12 rate was 96% (n/N = 3401/3546 [95% CI 95.2-96.5]). In patients with or without cirrhosis, SVR12 was comparable (96%). In patients with HCV GT1a, GT1b or GT4, SVR12 rates were 93%, 97% and 94%. In GT1b-infected patients with planned treatment for 8 weeks, SVR12 was 96%. In patients with ≥1 comorbidity (67%), SVR12 was 95%. 58% of patients received ≥1 comedication, and there was minimal impact on SVR12 rates using comedications for peptic ulcers and gastro-esophageal reflux disease, statins, antipsychotics or antiepileptics. Most comedications were maintained during treatment although 58% of patients changed their statin medication. AEs and serious AEs occurred in 26% and 3% of patients. Post-baseline Grade 3-4 laboratory abnormalities were rare (<3%), and discontinuation rates were low (<4%). Real-world evidence confirms the effectiveness of OBV/PTV/r ± DSV ± RBV in patients with HCV GT1 or GT4, regardless of common comorbidities or comedications, and is consistent with clinical trial results. Adverse safety outcomes may be limited by underreporting in the real-world setting.

The change in liver stiffness, controlled attenuation parameter and fibrosis-4 index for chronic hepatitis C patients with direct-acting antivirals

Background and aim

Transient elastography and fibrosis-4 index (FIB-4) have been proposed to access hepatic fibrosis and steatosis for patients with chronic liver disease. This study was to determine the changes of liver stiffness (LS), controlled attenuation parameter (CAP) value and FIB-4 and their associated factors for chronic hepatitis C (CHC) patients who underwent direct-acting antivirals (DAAs).

Patients and methods

Consecutive patients with CHC in advanced fibrosis or compensated cirrhosis undergoing paritaprevir/ritonavir/ombitasvir plus dasabuvir therapy and with LS and CAP before and 12 weeks after treatment were enrolled. The demographics, clinical characteristics and treatment outcomes were reviewed. The changes of LS, FIB-4, CAP and their associated factors were analyzed.

Results

A total of 213 patients (mean age: 63.7 years) with complete recommended treatment were enrolled. All patients achieved sustained virological response at 12 weeks (SVR12) of follow-up. The mean values of LS, CAP and FIB-4 index before treatment were 18.5kPa, 283dB/m and 5.05 respectively. While there was no significant change in CAP, LS and FIB-4 decreased significantly at the time of SVR12 (p<0.001). Compared with follow-up period, LS and FIB-4 decreased rapidly during DDAs. Multivariate analysis showed that higher baseline LS and FIB-4 were associated with greater reductions at the time of SVR12.

Conclusion

For CHC patients in advanced fibrosis or compensated cirrhosis, DAAs improved LS and FIB-4 index at SVR12. Higher baseline LS and FIB-4 contributed to greater reductions. However, there was no significant change in CAP value.

[EFFICACY AND SAFETY OF OMBITASVIR/PARITAPREVIR/RITONAVIR AND DASABUVIR IN PATIENTS WITH HCV 1B GENOTYPE INFECTION: REAL WORLD DATA]

The aim of this study was to investigate the efficacy and safety of the ombitasvir/ paritaprevir/ ritonavir and dasabuvir in patients with HCV, genotype-1b, in real clinical practice in Ukraine. The study included a total of 50 HCV infection genotype 1b patients receiving ombitasvir/ paritaprevir/ ritonavir and dasabuvir for 12 weeks. The patients were evaluated in respect of demographic, clinical and virological data, sustained virologic response (SVR) and adverse events. The mean age of patients was 52 years (40-60), 42% men, 20% treatment experienced, 42% with compensated cirrhosis. The SVR12 rate of all HCV genotype 1b patients was 96% (95%CI:86,3-99,5%). The most common adverse events were fatigue in 14 (28%) patients, diarrhea in 10 (20%) and headache in 12 (24%). In our study, the real world clinical practice data shows that ombitasvir/ paritaprevir/ ritonavir and dasabuvir for 12 weeks in HCV genotype 1b patients was well tolerated and resulted in 96% SVR12 regardless of previous treatment status and liver fibrosis stage.

Interferon-Free Regimen: Equally Effective in Treatment Naive and Experienced HCV Patients

INTRODUCTION AND AIM

Interferon-free regimen has been reported to be highly efficient in treatment of HCV infection, including patients with compensated cirrhosis. We compared the efficacy of Ombitasvir, Paritaprevir, Ritonavir, Dasabuvir and Ribavirin (OBT/PTV/r, with DSV and RBV) therapy in patients with chronic HCV genotype 1b infection and compensated cirrhosis with and without prior treatment experience with pegylated interferon and ribavirin (IFN/RBV).

MATERIAL AND METHODS

A prospective two-center study was conducted in Mures County Hospital and Brasov County Hospital, Romania in period November 2015-July 2016. Both treatment naïve and PegIFN/RBV experienced patients with chronic HCV genotype 1b infection received 12 weeks of OBT/PTV/r, with DSV and RBV. Sustained virologic response 12 weeks after the treatment and eventual discontinuation of therapy due to adverse events were assessed in order to estimate safety and efficiency of therapeutic regimen.

RESULTS

Fifty nine patients were included in study, 35 (59.3%) of them were previously treated with IFN/RBV. Forty four (74.5%) patients were previously diag-nosed with cirrhosis Child Pugh score 5, while 15 (25.4%) with Child Pugh score 6. All 59 patients achieved a SVR12 of 100% and one patient from treatment naïve cohort discontinued the therapy due to hyperbilirubinemia and encephalopathy. However viral load assessed at 12 weeks after discontinuation of therapy in this patient was undetectable. Conclusion An all-oral regimen of co-for-mulated OBT/PTV/r with DSV and RBV results in high rate of sustained virologic response at post-treatment week 12 among HCV GT1b infected patients associated with compensated cirrhosis, regardless of previous treatment experience with PegIFN/RBV.

The efficacy of paritaprevir/ritonavir/ombitasvir+dasabuvir and ledipasvir/sofosbuvir is comparable in patients who failed interferon-based treatment with first generation protease inhibitors - a multicenter cohort study

BACKGROUND

According to the EASL and AASLD guidelines, the recommended treatment for patients who failed to achieve a sustained virologic response (SVR) on prior interferon-based triple therapy with protease inhibitors (PI), is a combination of sofosbuvir and NS5A inhibitors. Polish national recommendations also allow the use of paritaprevir/ritonavir/ombitasvir+dasasbuvir±ribavirin (PrODR) in this group of patients. The aim of the study was to evaluate the efficacy and safety of PrODR vs. ledipasvir/sofosbuvir±RBV (LSR) in PI-experienced patients in real-life setting.

METHODS

Our analysis included patients registered in the nationwide, investigators initiated, multicentre EpiTer-2 database. Among 4530 patients registered, 335 with genotype 1 (93% 1b) were previously treated with IFN-based regimens with PIs: 127 with boceprevir (BOC), 208 with telaprevir (TVR). Patients with advanced fibrosis (F3/F4) were significantly predominant (BOC 28.4%/61.4%, TVR 18.8%/64.4%, respectively). Subjects were assigned to IFN-free retreatment as follows: BOC - 64 (50.4%) PrODR and 63 (49.6%) LSR; TVR- 103 (49.5%) PrODR and 105 (50.5%) LSR.

RESULTS

SVR rates were comparable for particular groups: BOC → PrODR- 100%; BOC → LSR - 98%; TVR → PrODR - 97%; TVR → LSR - 96% (intent-to treat analysis-ITT) and BOC → PrODR→100%; BOC → LSR - 99%; TVR → PrODR - 99%; TVR → LSR - 98% (modified intent-to treat analysis-mITT). Both treatment regimens had a favourable safety profile. Adverse events (AEs) were generally mild or moderate in severity. Three deaths were reported. The treatment was stopped due to AEs in five patients (three treated with PrODR and two with LSR).

CONCLUSION

Efficacy and safety of treatment with PrODR and LSR is comparable in BOC or TVR-experienced patients.