Switching from tenofovir disoproxil fumarate to besifovir dipivoxil maleate improves renal and bone health without compromising antiviral efficacy.
A new study led by Korea University College of Medicine, published in Clinical and Molecular Hepatology, demonstrates that switching from long-term tenofovir disoproxil fumarate (TDF) to besifovir (BSV) improves renal and bone safety in patients with chronic hepatitis B (CHB) without compromising antiviral efficacy. The study involved 153 patients who had been receiving TDF treatment for at least 48 weeks and were randomly assigned to receive either BSV 150 mg or continue with TDF 300 mg for another 48 weeks, with the primary endpoint assessing HBV DNA levels, a key marker of antiviral efficacy.1
The results showed that 100% of patients in the BSV group and 98.5% in the TDF group achieved a virologic response, defined as HBV DNA levels of less than 20 IU/mL. This demonstrated that BSV is non-inferior to TDF in terms of antiviral efficacy (95% CI -.01 to .04; P=1.000), confirming that BSV maintains similar effectiveness while offering a safer profile.1
More importantly, patients who switched to BSV experienced significant improvements in renal and bone health. The mean percentage change in estimated glomerular filtration rate (eGFR), which is used to measure kidney function, was slightly better in the BSV group (+1.67%) compared to the TDF group (-1.24%). Additionally, BSV-treated patients showed improvements in bone turnover biomarkers, and both hip and spine bone mineral density increased, suggesting enhanced bone strength compared to the TDF group.1
CHB, a liver infection caused by the hepatitis B virus (HBV), is estimated to affect over 250 million people worldwide. TDF is the most widely used antiviral agent for treating CHB; however, its long-term use has been associated with adverse effects on kidney function and bone health. This has prompted the exploration of alternative treatments with better safety profiles.2
BSV was shown to have similar antiviral efficacy to TDF, with 100% of BSV-treated patients and 98.5% of TDF-treated patients achieving low HBV DNA levels.
Patients switching to BSV experienced significant improvements in kidney function and bone density, including better eGFR and increased hip and spine bone mineral density.
The study highlights BSV as a potentially safer long-term treatment for chronic hepatitis B, offering improved renal and bone health compared to TDF.
These findings indicate that long-term treatment with BSV could be a safer alternative for CHB patients, especially those at risk for renal and bone complications due to prolonged TDF use. The results highlight the potential of BSV as a long-term treatment option that could offer better safety for patients with CHB.
The findings align with the ALLIANCE study, presented at CROI 2025, which compared the B/F/TAF regimen to DTG+F/TDF in HIV-HBV co-infected patients. Similar to the Korean study, TAF showed advantages in renal and bone safety, as well as improved liver health, including ALT normalization and better HBV suppression.3
Both studies reflect the trend of moving away from TDF, which, despite its antiviral efficacy, is associated with long-term adverse effects. TAF and BSV offer comparable antiviral efficacy while demonstrating improved safety profiles, particularly for renal and bone health. This shift supports efforts in ID research to balance antiviral efficacy with long-term safety, particularly for chronic viral infections like HIV and hepatitis B.
Additionally, these studies highlight the growing focus on personalized treatment, considering viral suppression and the individual patient's risk for adverse effects. By prioritizing safer therapies, this research aims to improve outcomes for patients with chronic viral infections and contributes to global health efforts to address these widespread diseases.
