Efficacy of entecavir and tenofovir in chronic hepatitis B under treatment in the public health system in southern Brazil

Tenofovir Alafenamide Fumarate, Tenofovir Disoproxil Fumarate and Entecavir: Which is the Most Effective Drug for Chronic Hepatitis B? A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

The therapeutic effect of tenofovir alafenamide fumarate (TAF), tenofovir disoproxil fumarate (TDF) and entecavir (ETV) on chronic hepatitis B (CHB) patients remains inconsistent. The aim of this study was to explore the differences in virological responses to TAF, TDF and ETV in patients with CHB.

METHODS

Literature searches were conducted of the PubMed, EMBASE, and the Cochrane Library databases to identify randomized controlled trials and observational studies published up to July 21, 2020. Statistical comparisons of virological response between TDF, ETV, and TAF were carried out with pooled odds ratio (OR) values.

RESULTS

The virological response in TDF-treated CHB patients was notably superior to that of the ETV-treated CHB patients after 12-weeks [OR=1.12, 95% confidence interval (CI): 0.89-1.41], 24-weeks (OR=1.33, 95% CI: 1.11-1.61), 48-weeks (OR=1.62, 95% CI: 1.16-2.25), 72-weeks (OR=1.43, 95% CI: 0.78-2.62), and 96-weeks (OR=1.56, 95% CI: 0.87-2.81) treatment. No significant difference was observed for the virological responses in CHB patients after 48-weeks treatment with TAF or TDF. The virological response in TDF+ETV-treated CHB patients was superior to that of TDF-treated CHB patients after 24-weeks, 48-weeks (OR=1.54, 95% CI: 1.17-2.02), 96-weeks, and 144-weeks.

CONCLUSIONS

The virological response in TDF-treated CHB patients was superior to that in ETV-treated CHB patients, but there was no significant difference between TAF and TDF. In addition, the therapeutic effect of TDF+ETV was superior to TDF alone.

Chronic hepatitis B genotype E in African migrants: response to nucleos(t)ide treatment in real clinical practice

Background

Hepatitis B virus (HBV) genotype E is a poorly studied genotype that almost exclusively occurs in African people. It seems to harbour intrinsic potential oncogenic activity and virological characteristics of immune scape but a paucity of information is available on clinical and virological characteristic of HBV genotype E-infected patients as well as on the efficacy of anti-HBV drugs for such patients. The increasing flow of migrants from high endemic HBV sub-Saharan Africa, where genotype E is the predominant one, to Western countries makes improving such knowledge critical in order to deliver proper medical care.

Methods

Prospective observational study of naïve patients of sub-Saharan origin treated for chronic HBV genotype E infection at a Tropical Medicine clinic sited in Spain from February 2004 to January 2018. The aim of the study was to describe the response of chronic HBV genotype E infection to nucleos(t)ide analogues (NA), entecavir or tenofovir, in real clinical practice.

Results

During the study period, 2209 sub-Saharan patients were assisted at our Tropical Medicine Unit and 609 (27.6%) had chronic HBV (CHB) infection. Genotype information was available for 55 naïve patients initiating treatment with NA (entecavir or tenofovir), 43 (84.3%) of them being genotype E, although 15 were excluded because they did not meet study inclusion criteria. Thus, a total of 28 CHB genotype E patients were included and followed for 24 months at least. Twenty-one patients were in HBeAg-negative chronic hepatitis phase and 7 patients in HBeAg-positive chronic hepatitis phase. After one year of treatment, among those with good adherence, 89.4% (17/19) of the HBeAg-negative patients and 80% of the HBeAg-positive ones had undetectable viral loads. Response rates reached 100% in both groups after 15–18 months of follow-up. Out of the 7 HBeAg-positive patients, 6 (85.7%) presented HBeAg loss in a median time of 31.8 months. Neither serious adverse effects nor hepatocarcinoma cases happened during the study period.

Conclusions

HBV genotype may influence disease progression and antiviral response. Our study provides precious information on the efficacy and safety of NA treatment for CHB genotype E infection, a fairly unknown genotype with and increasing epidemiological impact.

Wolbachia significantly impacts the vector competence of Aedes aegypti for Mayaro virus

Wolbachia, an intracellular endosymbiont present in up to 70% of all insect species, has been suggested as a sustainable strategy for the control of arboviruses such as Dengue, Zika and Chikungunya. As Mayaro virus outbreaks have also been reported in Latin American countries, the objective of this study was to evaluate the vector competence of Brazilian field-collected Ae. aegypti and the impact of Wolbachia (wMel strain) upon this virus. Our in vitro studies with Aag2 cells showed that Mayaro virus can rapidly multiply, whereas in wMel-infected Aag2 cells, viral growth was significantly impaired. In addition, C6/36 cells seem to have alterations when infected by Mayaro virus. In vivo experiments showed that field-collected Ae. aegypti mosquitoes are highly permissive to Mayaro virus infection, and high viral prevalence was observed in the saliva. On the other hand, Wolbachia-harboring mosquitoes showed significantly impaired capability to transmit Mayaro virus. Our results suggest that the use of Wolbachia-harboring mosquitoes may represent an effective mechanism for the reduction of Mayaro virus transmission throughout Latin America.

Comparison of oral fluid collection methods for the molecular detection of hepatitis B virus

BACKGROUND

This study aims to compare the efficiency of four oral fluid collection methods (Salivette, FTA Card, spitting and DNA-Sal) to detect HBV DNA by qualitative PCR.

MATERIALS AND METHODS

Seventy-four individuals (32 HBV reactive and 42 with no HBV markers) donated serum and oral fluid. In-house qualitative PCR to detect HBV was used for both samples and commercial quantitative PCR for serum.

RESULTS

HBV DNA was detected in all serum samples from HBV-infected individuals, and it was not detected in control group. HBV DNA from HBV group was detected in 17 samples collected with Salivette device, 16 samples collected by FTA Card device, 16 samples collected from spitting and 13 samples collected by DNA-Sal device. Samples that corresponded to a higher viral load in their paired serum sample could be detected using all oral fluid collection methods, but Salivette collection device yielded the largest numbers of positive samples and had a wide range of viral load that was detected.

CONCLUSION

It was possible to detect HBV DNA using all devices tested, but higher number of positive samples was observed when samples were collected using Salivette device, which shows high concordance to viral load observed in the paired serum samples.