Latest pharmacotherapy options for treating hepatitis C in HIV-infected patients

Prevalence of the potential drug-drug interactions between pangenotypic direct-acting antivirals and the concomitant medications associated with patients with chronic hepatitis C virus infection in Spain

OBJECTIVE

To determine the comorbidity and potential for drug-drug interactions (DDIs) among pangenotypic direct-acting-antivirals (pDAAs) and the concomitant medications associated with chronic hepatitis C (CHC) patients in routine clinical practice in Spain.

METHODS

Retrospective observational study. Included patients were ≥18 years, diagnosed with CHC, on antiviral treatment and required medical attention during 2017. Two groups were differentiated according to age ranges (<50 and ≥50 years). The variables collected were: age, gender, general/specific comorbidity, concomitant medication and potential DDIs (www.hep-druginteractions.org). The pDAAs analysed were: a) Sofosbuvir/Velpatasvir (SOF/VEL), b) Glecaprevir/Pibrentasvir (GLE/PIB) and c) Sofosbuvir/Velpatasvir/Voxilaprevir (SOF/VEL/VOX). Bivariate statistical analysis, P<.05.

RESULTS

3,430 patients with a mean age of 56.9 years and 60.3% males were enrolled. The average Charlson index was 0.8. Age range distribution: 18-49 years (28.9%) and ≥50 years (71.1%). The average number of medications per patient/year was 3.1 (SD 2.6). The total percentage of potential DDIs was: 8.6% minor DDIs, 40.5% clinically significant DDIs and 10.0% contraindicated medication. These DDIs were greater in patients ≥50 years (8.6%, 43.8% and 12.4%, respectively, P<.001). For all ages, SOF/VEL showed a lower percentage of: minor interactions (1.3% vs. 6.6% and 5.9%, P<.001); clinically significant interactions (53.4%, vs. 77.4% and 66.3%, P<.001) and contraindicated medication (1.7% vs. 8.3% and 10.7%, P<.001) compared to GLE/PIB and SOF/VEL/VOX, respectively.

CONCLUSIONS

Patients with CHC present high comorbidity and concomitant medication use, particularly elderly patients, thus implying a greater exposure to potential DDIs. Although the DDI rate was considerable with the three combinations analysed, SOF/VEL showed a lower number of clinically significant interactions.

Coinfection with HIV and hepatitis C virus in 229 children and young adults living in Europe

OBJECTIVE

To characterize children, adolescents and young adults infected with HIV/hepatitis C virus (HCV) vertically or before age of 18 years and living in Europe regarding mode of acquisition, HCV genotype, clinical status and treatment.

DESIGN

Retrospective, cross-sectional study using pooled data from 11 European paediatric HIV cohorts.

METHODS

Patients aged more than 18 months and less than 25 years, with HIV/HCV acquired vertically or in childhood, were included. Anonymized individual patient data were collected using a standard protocol and modified HIV Cohorts Data Exchange Protocol.

RESULTS

Of 229 patients included, 142 (62%) had vertically acquired infection. Median age at last follow-up was 16.2 years. Most children had HCV genotype 1 (101/184, 55%) or 3 (57/184, 31%). One-fifth (46/214) had a previous AIDS diagnosis (data missing on prior AIDS diagnoses for 15). At their last clinic visit, 70% (145/208) had no/mild immunosuppression (Centers for Disease Control and Prevention stage 1), and 131 of 179 on antiretroviral therapy had undetectable HIV RNA (assay thresholds varied from <20 to <150 copies/ml). Overall, 42% (86/204) had hepatomegaly in the previous year, and 55% (116/213) had alanine aminotransferase more than 40 IU/l at their last test. Of 97 patients with transient elastography, 12 had results more than 9 kPa; this was associated with duration of HCV infection (P = 0.033), but not with CD4 cell count, antiretroviral therapy use or sex in univariable analysis. Of 17 patients with liver biopsies, six had bridging fibrosis and one had cirrhosis. Twenty-five (11%) had been treated successfully for HCV.

CONCLUSION

The high proportion of patients with progressive liver disease underscores the need for close monitoring and earlier and more effective HCV treatment.

The Impact of PNPLA3 rs738409 SNP on Liver Fibrosis Progression, Portal Hypertension and Hepatic Steatosis in HIV/HCV Coinfection

BACKGROUND

Faster fibrosis progression and hepatic steatosis are hallmarks of HIV/HCV coinfection. A single nucleotide polymorphism (SNP) of the PNPLA3-gene is associated with development of non-alcoholic steatohepatitis and a worse outcome in alcoholic liver disease. However, the role of PNPLA3 rs738409 SNP on liver fibrosis and steatosis, portal hypertension, and virological response in HIV/HCV coinfection remains unclear.

METHODS

In this cross-sectional study PNPLA3 (rs738409) and IL28B (rs12979860) SNPs were determined in 177 HIV/HCV coinfected patients. Liver fibrosis and steatosis-staged by liver biopsy and transient elastography using the Controlled Attenuation Parameter (CAP)-and portal hypertension (hepatic venous pressure gradient, HVPG) were compared across PNPLA3 genotypes.

RESULTS

75 (42.4%) patients tested positive for a PNPLA3 minor/major risk allele (G/C:66; G/G:9) showed comparable fibrosis stages (median F2 vs. F2; p = 0.292) and similar amounts of hepatic steatosis (CAP: 203.5 ± 41.9 vs. 215.5 ± 59.7 dB/m; p = 0.563) as compared to patients without a PNPLA3 risk allele. Advanced liver fibrosis was neither associated with PNPLA3 (p = 0.253) nor IL28B-genotype (p = 0.628), but with HCV-GT3 (p = 0.003), higher BMI (p = 0.008) and higher age (p = 0.007). Fibrosis progression rate (0.27 ± 0.41 vs. 0.20 ± 0.26 units/year; p = 0.984) and HVPG (3.9 ± 2.6 vs. 4.4 ± 3.0 mmHg; p = 0.472) were similar in patients with and without PNPLA3 risk alleles. SVR rates to PEGIFN/RBV therapy were similar across PNPLA3 genotypes.

CONCLUSIONS

The presence of a PNPLA3 risk allele had no independent impact on liver disease or virological response rates to PEGIFN/RBV therapy in our cohort of HIV/HCV coinfected patients.

Structure-Based Design of Macrocyclic Coagulation Factor VIIa Inhibitors

On the basis of a crystal structure of a phenylpyrrolidine lead and subsequent molecular modeling results, we designed and synthesized a novel series of macrocyclic FVIIa inhibitors. The optimal 16-membered macrocycle was 60-fold more potent than an acyclic analog. Further potency optimization by incorporation of P1' alkyl sulfone and P2 methyl groups provided a macrocycle with TF/FVIIa Ki = 1.6 nM, excellent selectivity against a panel of seven serine proteases, and FVII-deficient prothrombin time EC2x = 1.2 μM. Discovery of this potent, selective macrocyclic scaffold opens new possibilities for the development of orally bioavailable FVIIa inhibitors.

Enhancing our understanding of current therapies for hepatitis C virus (HCV)

Great progress has been made in understanding the HCV genome and its molecular virology. This understanding has culminated in the development of direct-acting antiviral (DAA) agents targeting HCV viral proteins. Telaprevir (TVR) and boceprevir (BOC) were the first DAAs introduced for treatment of genotype 1 HCV in 2011; when used in combination with pegylated interferon (pegIFN) and ribavirin (RBV), these protease inhibitors improved efficacy in patients with chronic HCV infection compared to the traditional dual therapy. However, this combination was associated with adverse events that often led to early termination of therapy. In late 2013, the FDA approved a second wave of DAAs, sofosbuvir (SOF) and simeprevir (SMV). The use of SOF with SMV opened the door for IFN-free combination regimens. This combination was highly efficacious and well tolerated in patients with HCV genotype 1. Sofosbuvir and ledipasvir (LDV) fixed-dose oral combination (FDC) therapy, and paritaprevir/ritonavir, ombitasvir and dasabuvir ± RBV were recently approved, elevating sustained virologic response (SVR) rates to over 95 %. We are anticipating the approval of additional IFN-free regimens with comparable efficacy and tolerability but with the addition of pangenotypic coverage, fewer drug-drug interactions, and a high barrier to resistance. This review will summarize current management for chronic HCV infection.