Does fibrosis really regress in HIV/hepatitis C virus co-infected patients after treatment with direct antiviral agents?

Hepatitis C virus eradication in people living with human immunodeficiency virus: Where are we now?

Hepatitis C virus (HCV)/human immunodeficiency virus (HIV) co-infection still involves 2.3 million patients worldwide of the estimated 37.7 million living with HIV, according to World Health Organization. People living with HIV (PLWH) are six times greater affected by HCV, compared to HIV negative ones; the greater prevalence is encountered among people who inject drugs and men who have sex with men: the risk of HCV transmission through sexual contact in this setting can be increased by HIV infection. These patients experience a high rate of chronic hepatitis, which if left untreated progresses to end-stage liver disease and hepatocellular carcinoma (HCC) HIV infection increases the risk of mother to child vertical transmission of HCV. No vaccination against both infections is still available. There is an interplay between HIV and HCV infections. Treatment of HCV is nowadays based on direct acting antivirals (DAAs), HCV treatment plays a key role in limiting the progression of liver disease and reducing the risk of HCC development in mono- and coinfected individuals, especially when used at an early stage of fibrosis, reducing liver disease mortality and morbidity. Since the sustained virological response at week 12 rates were observed in PLWH after HCV eradication, the AASLD has revised its simplified HCV treatment algorithm to also include individuals living with HIV. HCV eradication can determine dyslipidemia, since HCV promotes changes in serum lipid profiles and may influence lipid metabolism. In addition to these apparent detrimental effects on the lipid profile, the efficacy of DAA in HCV/HIV patients needs to be considered in light of its effects on glucose metabolism mediated by improvements in liver function. The aim of the present editorial is to describe the advancement in HCV treatment among PLWH.

Benefits of rilpivirine for liver stiffness in HIV/HCV-coinfected patients

BACKGROUND

Rilpivirine (RPV) is an antiretroviral drug characterized by good tolerability and a favorable liver safety profile. Recent research has shown that RPV ameliorates liver fibrosis in animal models of various chronic liver diseases. Our study aimed to analyze the effect of RPV on liver fibrosis by assessing changes in liver stiffness using transient elastography.

METHODS

Retrospective cohort study of HIV-infected patients who were exposed and not exposed to RPV. The change in liver stiffness during the period between two transient elastography measurements was analyzed and compared for patients exposed and not exposed to RPV.

RESULTS

We selected 118 RPV-exposed and 118 non-RPV-exposed HIV-infected patients. Median time between transient elastography (TE) measurements was 50 (29-68) months. A repeated-measures general linear model based on the main clinical characteristics revealed a significant decrease in the TE value of -0.8kPa in non-RPV-exposed patients (p=0.254) and -1.6kPa in the RPV-exposed group (p<0.001). The subgroup analysis showed a significant reduction in the TE value only patients cured of hepatitis C (RPV-exposed, -2.8kPa [p<0.001]; non-RPV-exposed, -1.1kPa [p=0.22]).

CONCLUSION

RPV-based antiretroviral regimens significantly reduced liver stiffness, as measured by TE, in patients cured of chronic hepatitis C.

Causes and outcomes of hepatic fibrosis in persons living with HIV

PURPOSE OF REVIEW

The epidemiology of liver disease in people living with HIV has evolved since the arrival of effective hepatitis C virus (HCV) treatment. Nonalcoholic fatty liver disease (NAFLD) in HIV patients is highly prevalent while hepatitis D, hepatitis E, and occult hepatitis B remain underappreciated. We discuss mechanisms of fibrosis in HIV and review clinical outcomes of HIV-associated liver diseases.

RECENT FINDINGS

HIV-HCV co-infection is receding as a cause of progressive liver disease, but fibrosis biomarkers after HCV treatment remain elevated. Antiretroviral therapy (ART) with anti-hepatitis B virus (HBV) activity promotes stable liver disease, but oversimplifying ART regimens in unrecognized suppressed HBV may lead to activation of HBV. A high prevalence of fibrosis and rapid progression of fibrosis are seen in HIV-associated NAFLD, with visceral fat as a major risk factor. Newer ART such as integrase strand inhibitors may have limited intrinsic hepatoxicity but do increase weight, which may secondarily lead to hepatic steatosis. Promising therapies for HIV-associated NAFLD include tesamorelin and CCR5 blockade agents.

SUMMARY

Our understanding of the natural history and pathogenesis of liver diseases in HIV has advanced and adapted to the changing landscape of liver disease in this population. Future research should evaluate long-term clinical and histological outcomes, prevention strategies, and treatment options to improve morbidity and mortality in HIV-related liver diseases.

Short- and Long-Term Immunological Responses in Chronic HCV/HIV Co-Infected Compared to HCV Mono-Infected Patients after DAA Therapy

Background: Direct-acting antivirals (DAAs) treatment, although highly efficacious for the treatment of hepatitis C virus (HCV) infection, may not completely reconstitute the HCV-mediated dysregulated immune system, especially in patients co-infected with human immunodeficiency virus (HIV) and HCV. Objectives: We aimed to evaluate the impact of HCV eradication following DAA therapy on the immune system and liver disease improvement through comparative monitoring of 10 HCV mono-infected and 10 HCV/HIV co-infected patients under combined antiretroviral therapy (cART). Early and late longitudinal phenotypic changes in peripheral blood mononuclear cell (PBMC) subsets, T-cell activation, differentiation and exhaustion, as well as inflammatory biomarkers, indoleamine 2-3 dioxygenase (IDO) activity, and liver stiffness, APRI and FIB-4 scores were assessed. Materials and Methods: Samples were obtained at baseline (T0), week 1 (T1), week 2 (T2), week 12 (T3, end of treatment, EOT), and month 9 (T4, end of follow-up, 36 weeks post EOT). Results: All patients achieved a sustained virological response (SVR 12) after DAA treatment. Overall, changes of the T-cell immune phenotypes were greater in HCV/HIV co-infected than in HCV mono-infected, due to an increase in CD4+ and CD8+ T-cell percentages and of CD8+ T-cell activation and memory markers, in particular at the end of follow-up. On the other end, HCV mono-infected showed changes in the activation profile and in the memory CD4+ T-cell compartment. In HCV/HIV co-infected, a decrease in the IDO activity by DAA treatment was observed; conversely, in HCV mono-infected, it resulted unmodified. Regarding inflammatory mediators, viral suppression was associated with a reduction in IP-10 levels, while interferon regulatory factor (IRF)-7, interferon (IFN)-β, and interferon (IFN)-γ levels were downregulated during therapy and increased post therapy. A decrease in liver stiffness, APRI, and FIB-4 scores was also observed. Conclusions: Our study suggests that, although patients achieved HCV eradication, the immune activation state in both HCV mono-infected and HCV/HIV co-infected patients remains elevated for a long time after the end of DAA therapy, despite an improvement of liver-specific outcomes, meanwhile highlighting the distinct immunophenotypic and inflammatory biomarker profile between the groups of patients.

A Tale of Two Viruses: Immunological Insights Into HCV/HIV Coinfection

Nearly 2.3 million individuals worldwide are coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Odds of HCV infection are six times higher in people living with HIV (PLWH) compared to their HIV-negative counterparts, with the highest prevalence among people who inject drugs (PWID) and men who have sex with men (MSM). HIV coinfection has a detrimental impact on the natural history of HCV, including higher rates of HCV persistence following acute infection, higher viral loads, and accelerated progression of liver fibrosis and development of end-stage liver disease compared to HCV monoinfection. Similarly, it has been reported that HCV coinfection impacts HIV disease progression in PLWH receiving anti-retroviral therapies (ART) where HCV coinfection negatively affects the homeostasis of CD4⁺ T cell counts and facilitates HIV replication and viral reservoir persistence. While ART does not cure HIV, direct acting antivirals (DAA) can now achieve HCV cure in nearly 95% of coinfected individuals. However, little is known about how HCV cure and the subsequent resolution of liver inflammation influence systemic immune activation, immune reconstitution and the latent HIV reservoir. In this review, we will summarize the current knowledge regarding the pathogenesis of HIV/HCV coinfection, the effects of HCV coinfection on HIV disease progression in the context of ART, the impact of HIV on HCV-associated liver morbidity, and the consequences of DAA-mediated HCV cure on immune reconstitution and HIV reservoir persistence in coinfected patients.

Liver Fibrosis in Human Immunodeficiency Virus (HIV)-Hepatitis C Virus (HCV) Coinfection Before and After Sustained Virologic Response: What Is the Best Noninvasive Marker for Monitoring Regression?

BACKGROUND

Noninvasive markers of liver fibrosis such as aspartate aminotransferase-to-platelet ratio (APRI) and transient elastography (TE) have largely replaced liver biopsy for staging hepatitis C virus (HCV). As there is little longitudinal data, we compared changes in these markers before and after sustained virologic response (SVR) in human immunodeficiency virus (HIV)-HCV coinfected patients.

METHODS

Participants from the Canadian Coinfection Cohort study who achieved SVR after a first treatment with either interferon/ribavirin or direct acting antivirals (DAAs), with at least 1 pre- and posttreatment fibrosis measure were selected. Changes in APRI or TE (DAA era only) were modeled using a generalized additive mixed model, assuming a gamma distribution and adjusting for sex, age at HCV acquisition, duration of HCV infection, and time-dependent body mass index, binge drinking, and detectable HIV RNA.

RESULTS

Of 1981 patients, 151 achieved SVR with interferon and 553 with DAAs; 94 and 382 met inclusion criteria, respectively. In the DAA era, APRI increased (0.03 units/year; 95% credible interval (CrI): -.05, .12) before, declined dramatically during, and then changed minimally (-0.03 units/year; 95% CrI: -.06, .01) after treatment. TE values, however, increased (0.74 kPa/year; 95% CrI: .36, 1.14) before treatment, changed little by the end of treatment, and then declined (-0.55 kPa/year; 95% CrI: -.80, -.31) after SVR.

CONCLUSIONS

TE should be the preferred noninvasive tool for monitoring fibrosis regression following cure. Future studies should assess the risk of liver-related outcomes such as hepatocellular carcinoma according to trajectories of fibrosis regression measured using TE to determine if and when it will become safe to discontinue screening.

Fibrosis improvement in patients with HCV treated with direct-acting antivirals

BACKGROUND AND AIM

More prospective studies are needed to characterize fibrosis improvement in patients with hepatitis C virus (HCV) who are treated with direct-acting antivirals (DAAs). The aims of this study were to assess changes in elastography scores from baseline to 1-year follow-up in patients with HCV, to identify factors that were independently associated with improvement in fibrosis staging in patients who receive treatment, and to identify factors that were independently associated with no improvement in fibrosis staging among patients who achieved sustained virologic responses (SVR).

METHODS

Ultrasound elastography and laboratory tests were performed and collected at baseline and at 1-year follow-up for patients who received HCV treatment and for those who did not receive treatment (n = 240). Binomial logistic regression was used to examine factors that were independently associated with improvement in fibrosis staging.

RESULTS

In patients who achieved SVR, the mean fibrosis score decreased significantly (-1.3) from 7.4 (2.3) before treatment to 6.1 (2.0) after treatment (P = 0.00). In multivariate analysis of patients who received treatment, higher pre-treatment fibrosis stages [odds ratio (OR) = 13.02, P < 0.00] were positively associated with improvement in fibrosis staging at 1-year follow-up. Higher BMI (OR = 0.93, P < 0.05) was negatively associated with improvement in fibrosis staging.

DISCUSSION

This study supports the growing body of literature that suggests fibrosis regression is achievable in a significant number of patients who achieve SVR with all-oral DAA regimens. Equally important, fibrosis regression is more likely to occur in patients with advanced stages of fibrosis and less likely in patients who are obese.

Modifications of liver stiffness and CXCL4, TGF-β1 and HGF are similar in HCV- and HIV/HCV-infected patients after DAAs

The objective of this work was to identify predictive factors of fibrosis regression after direct antiviral agents (DAAs) in HCV-monoinfected and HIV/HCV-coinfected patients. This was a prospective study of HCV-monoinfected (n = 20), HIV/HCV-co-infected (n = 66) patients and healthy controls (n = 15). Patients had started DAAs and achieved sustained virological response. Liver stiffness (LS) and serum concentrations of profibrotic transforming growth factor (TGF)-β1 and CXC chemokine ligand 4 (CXCL4) and antifibrotic HGF hepatocyte growth factor (HGF) were analyzed at baseline (M0) and 12 months after starting DAAs (M12). A M12 LS achievement of ≤ 9.5 kPa was considered the cutoff point to discharge from a liver clinic. The LS decrease from M0 to M12 was 34%. No significant differences were observed in LS decline between HCV- and HIV/HCV-infected individuals. Changes of serum CXCL4, TGF-β1 and HGF levels did not correlate with LS improvement. 16 out from 56 patients (28%) with a baseline LS > 9.5 achieved a M12 LS ≤ 9.5. HCV-monoinfected and HIV/HCV coinfected patients experienced a significant reduction of LS after sustained virological response. This improvement did not correlate with changes in serum profibrotic or antifibrotic markers. A 29% of those with a baseline LS > 9.5 achieved a LS under this cutoff point.

Insights Into the Pathophysiology of Liver Disease in HCV/HIV: Does it End With HCV Cure?

HCV-HIV coinfected patients exhibit rapid progression of liver damage relative to HCV monoinfected patients. The availability of new directly acting antiviral agents has dramatically improved outcomes for coinfected patients as sustained virologic response rates now exceed 95% and fibrosis-related parameters are improved. Nevertheless, coinfected patients still have a higher mortality risk and more severe hepatocellular carcinoma compared to HCV monoinfected patients, implying the existence of pathways unique to people living with HIV that continue to promote accelerated liver disease. In this article, we review the pathobiology of liver disease in HCV-HIV coinfected patients in the directly acting antiviral era and explore the mechanisms through which HIV itself induces liver damage. Since liver disease is one of the leading causes of non-AIDS-related mortality in HIV-positive patients, enhancing our understanding of HIV-associated fibrotic pathways will remain important for new diagnostic and therapeutic strategies to slow or reverse liver disease progression, even after HCV cure.