Efficacy and Safety of Tenofovir Plus Entecavir Combination Therapy Versus Tenofovir Monotherapy in Chronic Hepatitis B Virus Patients With Resistance or Partial Response to Entecavir: A Systematic Review and Meta-analysis

Background and objectives

Chronic hepatitis B virus remains a significant cause of liver disease in the developing world, leading to sequelae such as hepatocellular carcinoma. While entecavir (ETV) serves as a first-line treatment, its growing resistance rates underscore the need to explore viable alternatives. Tenofovir disoproxil fumarate (TDF) monotherapy and entecavir plus tenofovir (TDF + ETV) combination therapy are both employed as treatments, but one's efficacy over another is in question. This meta-analysis aims to investigate any primacy of either treatment.

Methods

We conducted a comprehensive literature search across PubMed/Medline, Embase, Cochrane Central, Web of Science, and China National Knowledge Infrastructure from inception till 7th October 2024. Studies comparing the safety and efficacy of TDF monotherapy versus TDF + ETV combination therapy in patients resistant to entecavir were considered. Data about the virologic response (VR), virologic breakthrough, HbeAg seroconversion, HbeAg/HbsAg seroclearance, and alanine aminotransferase normalization were extracted. Relative risks (RRs) and their corresponding 95% confidence intervals (CIs) were calculated, pooled, and analyzed in a random-effects model. P-value <0.05 was regarded as significant for all analyses.

Results

Nine studies, comprising 335 patients undergoing monotherapy and 352 patients undergoing combination therapy, satisfied the criteria. TDF + ETV combination therapy was found slightly advantageous to TDF monotherapy, stimulating a VR at 48 weeks (RR 1.081 95% CI: [1.001-1.167] P = 0.046, I2 = 0%), along with the HbeAg seroconversion rate (RR 1.711 95% CI: [1.005-2.913] P = 0.048, I2 = 0%). There were no significant adverse events in individual studies to warrant a meta-analysis.

Conclusions

TDF + ETV shows slightly better efficacy to TDF monotherapy over a 48-week treatment regimen, with minimal safety concerns. However, further high-quality studies like randomized controlled trials are needed to further solidify conclusions, with this meta-analysis only achieving borderline significances.

Registration

This review is registered on the PROSPERO database (ID: CRD42024581443).

Switching to tenofovir vs continuing entecavir for hepatitis B virus with partial virologic response to entecavir: a randomized controlled trial

Entecavir 0.5 mg (ETV) is widely used among treatment-naïve chronic hepatitis B (CHB) patients. However, 10%-30% of patients show partial virologic response (PVR) to the drug. If the hepatitis B virus (HBV) continues to replicate, the underlying liver disease may progress. Herein, we compared the efficacy of switching to tenofovir disoproxil fumarate (TDF) with that of continuing ETV in CHB patients with PVR to ETV. This was an open-label randomized controlled trial including CHB patients who had been receiving 0.5 mg of ETV for >12 months, but who still had detectable HBV DNA levels of >60 IU/mL without known resistance to ETV. Sixty patients were enrolled and 45 qualified for the study: Twenty-two patients were randomly assigned into the TDF group and 23 into the ETV group. After 12 months of treatment, the virologic response rate (HBV DNA <20 IU/mL) was significantly higher in the TDF group than in the ETV group, as measured using per-protocol analysis (55% vs 20%; P = .022) and intention-to-treat analysis (50% vs 17.4%; P = .020). The reduction in HBV DNA was greater (-1.13 vs -0.67 log10 IU/mL; P = .024), and the mean HBV DNA level was lower (1.54 vs 2.01 log10 IU/mL; P = .011) in the TDF group than in the ETV group. In conclusion, to achieve optimal response in CHB patients with PVR to ETV, switching to TDF would be a better strategy than continuing ETV. Appropriate modification of therapy would further improve the outcome of chronic HBV infection.

Comparison of the Efficacy of Tenofovir Versus Tenofovir plus Entecavir in the Treatment of Chronic Hepatitis B in Patients With Poor Efficacy of Entecavir: A Systematic Review and Meta-analysis

PURPOSE

This study aimed to compare the efficacy between tenofovir disoproxil fumarate (TDF) and TDF plus entecavir (ETV) combination therapy in patients with chronic hepatitis B (CHB) with a poor response to ETV.

METHODS

We searched the China National Knowledge Infrastructure (CNKI), PubMed, EMBASE, and SCOPE libraries for articles using the keywords chronic hepatitis B virus or CHB or HBV, entecavir or ETV, and tenofovir or TDF.

FINDINGS

Five studies (from CNKI and PubMed) with a total of 408 patients met the inclusion criteria: 212 patients in the TDF group and 196 patients in the TDF plus ETV group. The rates of viral suppression between the 2 groups were comparable at weeks 24 and 48 of treatment (P = 0.546 vs P = 0.818). In addition, the subanalysis revealed that no significant differences were observed in the rates of viral suppression between the 2 groups at week 24 (subgroup 1 [partial response to ETV]: P = 0.822; subgroup 2 [resistance to ETV]: P = 0.294) and week 48 (subgroup 1: P = 0.797; subgroup 2: P = 0.545). No significant differences were found in alanine aminotransferase normalization, hepatitis B e antigen loss, hepatitis B e antigen seroconversion, virologic breakthrough, and tolerability between the 2 groups at weeks 24 and 48. Therefore, the results suggest that TDF monotherapy should be chosen for patients with CHB with a poor response to ETV for reasons of economy and convenience.

IMPLICATIONS

We conclude that TDF monotherapy is comparable to TDF-ETV combination therapy for patients with a poor response to ETV; thus, TDF monotherapy may be a better choice for these patients. However, because of the limited citations in this meta-analysis, complete and systematic evidence is needed to evaluate the differences in efficacy and tolerability between TDF and TDF-ETV. Larger and longer randomized clinical trials and further studies should be conducted to verify the results.