Tenofovir Alafenamide Fumarate Might be a Feasible Alternative in Chronic HBV Infected Patients Treated with Other Antiviral Drugs
Introduction
Hepatitis B Virus (HBV), a common blood-borne pathogen, continues to be a significant global health concern despite vaccination programs and effective antiviral drugs. The European Association for the Study of Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD) have recently included tenofovir alafenamide fumarate (TAF) as one of the firstâ€line agents for HBV. According to the recommendations released by the Saudi Association for the Study of Liver Diseases and Transplantation (SASLT) in 2014, the recommended anti-HBV agents in the country were entecavir (ETV) and tenofovir disoproxil fumarate (TDF), along with lamivudine (LAM), telbivudine, adefovir, and pegylated interferon.
Aim
This study evaluated the efficacy of TAF, after switching from other antiviral drugs and its role in maintaining the clinical characteristics of HBV patients within normal range.
Method
Study Design
- Retrospective observational study
Patient Profile
- Patients aged ≥ 18 years and < 80 years with a confirmed diagnosis of chronic HBV infection
- Received oral antiviral (OAV) treatment for at least six months (± two weeks) prior to switching to TAF as per routine medical practice
- Patients attending the study site clinic with available patient records before and after switching to TAF
Treatment Strategy
- A total of 71 HBV patients were enrolled.
- Medical history, vital signs, HBV deoxyribonucleic acid (HBV-DNA) plasma levels and biochemistry test results for the alanine aminotransferase (ALT), aspartate aminotransferase (AST), and serum creatinine levels were collected at three time points, including baseline (T1), time of switching to TAF (T2), and six months after switching to TAF (T3).
End Points
- Changes in mean plasma HBV-DNA levels
- Changes from baseline in liver enzymes
Results
- The baseline characteristics of the cohort was as below
- Mean age of 45± 12 years.
- Mean disease duration of 13.65±6.5 years.
- The mean HBV DNA levels at baseline were high (> 2x106 IU/mL) while 88.7% were negative for HBeAg.
- The mean levels of AST, ALT, and serum creatinine were within the normal range of each parameter
- Majority of patients had F1 stage fibrosis (18.3%), followed by F4 (12.7%), F0 (8.5%), F3 (8.5%), and F2 (7.0%).
- Liver ultrasound results showed that 53.5% had normal liver ultrasonography while approximately 20% of patients had the ultrasonographic features of fatty liver and 15.5% of patients had the ultrasonographic signs of cirrhosis
- There was significant reduction in the HBV-DNA levels from the time of switching to TAF till six months later as seen in Figure 1; p<0.05.
- The levels of ALT and AST also reduced at 6 months after switching to TAF as seen in Table 1.
|
Enzyme |
T1 |
T3 |
P value |
|
ALT (U/L) |
29.05 |
27 |
0.328 |
|
AST (U/L) |
21.34 |
20.7 |
0.410 |
- There was no statistically significant reduction in the serum creatinine levels after switching to TAF; p=0.472
- However, ALT, AST and serum creatinine showed a detectable maintenance level.
- There were no significant differences in fibrosis score and other biochemical parameters at different timepoints
Conclusions
- Treatment with tenofovir alafenamide fumarate (TAF) was a feasible, well-tolerated, and safe alternative in chronic hepatitis B virus infected patients who are treated with tenofovir disoproxil fumarate, entecavir, lamivudine and adefovir.
- TAF was effective in maintaining significant viral suppression and higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST) normalization rates 6 months after switching to TAF.
Cureus 12(9): e10380. Doi:10.7759/cureus.10380.
