Hepatitis C vaccine: supply and demand

Geospatial epidemiology of hepatitis C infection in Egypt 2017 by governorate

Background

Geographic Information Systems (GIS) and spatial epidemiological methods may provide a basis for disease investigation through which hotspots and disease determinants can be identified. Applying these methods for hepatitis C virus (HCV) in Egypt would support a more effective strategy to control its transmission. Therefore, this study used GIS software to draw one of the first HCV maps in Egypt elucidating and analyzing geographical and epidemiological differences in HCV distribution within the country.

Methods

A cross-sectional survey of 21 governorates (n = 12169, 8080 rural, 3733 urban and 356 slums areas) was completed. All participants were interviewed regarding potential exposures to HCV. Third generation ELISA was used to test serum for HCV antibody. Quantitative real-time RT-PCR was used to test anti-HCV positive subjects for HCV-RNA.

Results

The participants ranged in age from 14-90 years. Overall, anti-HCV sero-prevalence was 14.8%. The prevalence of HCV-RNA, was 9.5%. Proportionally, 65.8% of anti-HCV positives were positive for HCV-RNA. The map of Egyptian governorates highlighted the darkest spot of HCV infection in Menoufeya (37.8%) followed by Beni Suef (29.2%) and Minya (28.6%). Anti-HCV prevalence was higher among males and logistic regression models revealed a strong independent association with increasing age, rural residence and parenteral anti-schistosomal therapy.

Conclusions

Rural residences and HCV hotspots should be prioritized for HCV prevention programs. The unique age distribution first shown in this study shows that the older age groups (≥60 years old) constitutes a considerable reservoir of infection and must not be neglected.

AS, Liz AL, Lisset GF, Sacha LDV, Elena FB. Clinical Evaluation of Terap C Vaccine in Combined Treatment with Interferon and Ribavirin in Patients with Hepatitis C

BACKGROUND

An estimated 170 million individuals worldwide are infected with the hepatitis C virus (HCV). Although treatment options using a combination of pegylated interferon and ribavirin (P-IFN/RBV) are available, sustained clearance of the virus is only achieved in approximately 40% of individuals infected with HCV genotype 1. Recent advances in the treatment of HCV using directly acting antiviral agents have been achieved; however, treatment can be very expensive and is associated with substantial side effects. The development of a new treatment modality is needed. One possible modality could be specific immunotherapy. Terap C is a therapeutic vaccine candidate composed of pIDKE2, a plasmid expressing HCV structural antigens, with a recombinant HCV core protein, Co.120.

OBJECTIVE

To assess the safety and efficacy of concomitant therapy with the candidate vaccine, Terap C, IFN α-2b and ribavirin in untreated individuals with HCV genotype 1 infection.

METHODS

This was a Phase II randomized, placebo-controlled, double-blind clinical trial evaluating the safety and efficacy of Terap C concomitant with IFN α-2b/RBV in 92 treatment-naïve patients with HCV genotype 1 infection. The study was conducted at the Gastroenterology Institute in Havana, Cuba. Patients were randomly assigned to 1 of 5 groups. The control group (Group 1) received IFN α-2b/RBV and placebo for 48 weeks. Groups 2 and 3 were administered Terap C 6 and 9 times, respectively, in addition to standard IFN α-2b/RBV treatment. In groups 4 and 5, Terap C was introduced 12 weeks after the initiation of IFN α-2b/RBV and administered 6 and 9 times, respectively, concomitant with IFN α-2b/RBV.

RESULTS

All patients showed some adverse events. Out of 3615 adverse events, only 18.8% were considered to be probably associated with administration of Terap C. Most events (47.4%) were considered to be improbably associated with of administration Terap C. Only 33.8% were considered possibly temporarily associated with Terap C, and can be explained by the use of conventional IFN α-2b + RBV or by HCV itself. The most common adverse events (≥65%) observed were pain at the injection site, headache, asthenia, psychiatric disturbances, fever, and gastrointestinal symptoms. Regarding sustained virological response, a 20% superiority was observed in the patients who received concomitant Terap C treatments from the beginning of the study compared with those who started after Week 12.

CONCLUSIONS

Vaccination with Terap C in patients with chronic HCV infection was safe and well tolerated. Clinical trial protocol code: IG/VHI/HC/0701; Public Register Code: RPCEC00000074.

A single amino acid change in the hypervariable region 1 of hepatitis C virus genotype 4a aids humoral immune escape

Longitudinal analysis of chronic hepatitis C virus (HCV) infection has shown that the virus has several adaptive strategies that maintain persistence and infectivity over time. We examined four serum samples from the same chronically infected HCV genotype 4a patient for the presence of IgG antibody-associated virus. RNA was isolated from antibody-associated and antibody-free virions. Subsequent to sequence analysis, 27 aa hypervariable region 1 (HVR1) peptides were used to test the humoral immune escape. We demonstrated that differential peptide binding of Fab was associated with a single amino acid change. We provide direct evidence of natural humoral immune escape by HCV within HVR1.

Pretreatment serum macrophage inflammatory protein (MIP)-1 levels predict sustained virological responses to re-treatment in patients with chronic hepatitis C virus infection

BACKGROUND

There are few predictors of the virological response in patients who are re-treated with antiviral therapies. In this study, we evaluated the levels of chemokines that bind to C-C chemokine receptor type 5 (CCR5) and their impact on combination therapy in both treatment-naïve and treatment-experienced patients chronically infected with hepatitis C virus (HCV).

METHODS

Longitudinal analysis of CCR5 chemokines was performed using the multiplex Bio-Rad 27-plex assay in 56 treatment-naïve and 24 treatment-experienced patients with chronic HCV infection during combination therapy with peginterferon alfa and ribavirin. A group of healthy donors was included as the control (n=11).

RESULTS

The pretreatment level of macrophage inflammatory protein 1 (MIP-1) was determined to be an independent predictor, with an ideal predictive threshold for sustained virological response of 95.23 pg/ml. A rapid decline in HCV RNA was observed in patients with a pretreatment MIP-1 level of <95.23 pg/ml, while a slow reduction was measured in patients with levels of ≥95.23 pg/ml (p=0.014). Of note, the dynamics of MIP-1 further indicated that a lower level at baseline and at treatment week 12 was significantly associated with a favorable outcome of antiviral therapy (p=0.014), especially in treatment-experienced patients (p=0.04), while a higher level of MIP-1beta correlated with the elevation of transaminases.

CONCLUSIONS

Serum MIP-1 is an independent and effective predictor of early and sustained virological response in chronically HCV-infected patients undergoing re-treatment.

Hepatitis C virus nonstructural protein specific T cells are associated with virological responses to combination therapy in chronic HCV patients

BACKGROUND

Virus-specific T-cell responses play a major role in antiviral immune response. However, the effect of hepatitis C virus (HCV)-specific T-cell responses on combination therapy still remains controversial.

AIMS

To identify the association between HCV-specific T cell responses and efficiency of combination therapy.

METHODS

To address this issue, a longitudinal analysis of HCV-specific T-cell responses to overlapping peptides covering HCV-nonstructural protein (NS) was performed using ELISpot assay in 48 chronically infected HCV-1b patients during combination treatment with peginterferon-alfa and ribavirin.

RESULTS

Fifty-two percent of chronic HCV patients showed detectable HCV-NS3, NS4 or NS5A specific T-cell responses before therapy, with NS3 appearing to be the most immunodominant protein followed by NS5A and NS4. In addition, the percentage of patients responding to peptide stimulation was higher in patients with sustained virological response (SVR) when compared with those without SVR. Dynamics of HCV-NS-specific T-cell responses were further analysed; we found that HCV-specific T-cell responses maintained higher levels at 12 weeks into treatment in patients with SVR. In contrast, HCV-specific T-cell responses in patients without SVR declined significantly at 4 weeks into treatment and maintained low levels at 12 weeks.

CONCLUSION

We found that the HCV-specific T-cell responses were associated with good viral control in patients with combination therapy.

The effect of cytokine profiles on the viral response to re-treatment in antiviral-experienced patients with chronic hepatitis C virus infection

BACKGROUND

There have been few studies on the potential immunological factors associated with viral controls in antiviral-experienced patients on a second round of combination therapy. In this study, we evaluated the level of systemic cytokines and potential impact on combination therapy in both antiviral-naïve and -experienced patients chronically infected with hepatitis C virus.

METHODS

Longitudinal analysis of 27 cytokines and chemokines was performed using the multiplex Biorad 27 plex assay in 37 antiviral-naïve and 24 experienced chronically HCV-1b-infected patients during combination therapy with peginterferon-alfa and ribavirin. A group of healthy donors was included as the control (n=11).

RESULTS

Fifty percent of antiviral-experienced chronically HCV-patients could achieve a delayed and slow virologic response after 48 weeks combination therapy, comparing with an early and fast virologic response in antiviral-naïve patients. A distinction of immune mediators profiling before and during antiviral therapy between antiviral-naïve and -experienced patients was identified, IL-4, IFN-γ and CCL-3 (MIP-1a) were significantly higher in naïve patients than those in experienced patients (P=0.005, 0.047 and 0.017, respectively) while G-CSF in naïve was lower than in experienced patients (P<0.05). Notably, higher Th1 type cytokine IFN-γ and lower Th2 type cytokine IL-4 at baseline and week 4 were associated with HCV clearance in naïve patients, and a similar trend appeared at week 12 in experienced patients.

CONCLUSIONS

We found a successful second round therapy in antiviral-experienced patients appears to be associated with the host immune response. Dominant Th1-polar cytokines, especially IFN-γ, is a potential predictor of viral responsiveness.