Continuous entecavir can be a safe and effective treatment for patients with chronic hepatitis B, according to data released recently.
In a retrospective analysis, researchers evaluated 474 nucleos(t)ide-naive patients with chronic hepatitis who received continuous daily treatments of 0.5 mg entecavir for 4 years, with a median follow-up of 2.4 years. Hepatitis B e antigen-positive (HBeAg-positive) was detected in 47% of patients. At baseline, the mean HBV DNA level was 6.7 log10 copies/mL and the mean alanine aminotransferase (ALT) level was 70 IU/L.
HBV DNA was undetectable in 353 of 402 evaluable patients after 1 year, with ALT greater than 5x ULN (OR=11.9; 95% CI, 3.3-41.7), HBeAg-negative status (OR=8.5; 95% CI, 2.3-31.2) and DNA levels less than 7.6 log10 copies/mL (OR=10.0; 95% CI, 4.3-23.1) observed as significant predictive factors. After 2 years, 262 of 281 evaluable patients had undetectable levels, with ALT greater than 5x ULN (OR=16.7; 95% CI, 2.0-136.8) and DNA levels less than 7.6 log10 copies/mL (OR=121.7; 95% CI, 15.3-965.9) indicated as predictive factors. In 3 years of treatment, 156 of 165 evaluable patients had undetectable levels, with only a DNA level of less than 7.6 log10 copies/mL (OR=15.8; 95% CI, 43.1-79.9) as a significant factor. All evaluable patients who tested HBeAg-negative had undetectable levels of HBV DNA after 4 years of treatment, compared with 93% of patients who tested positive. An HBV DNA level of 7.6 log10 copies/mL or less was found to be an independent predictor of undetectable DNA levels after 4 years (OR=30.6; 95% CI, 5.4-173.3).
Five patients experienced virological breakthrough during the study, two of whom (0.4%) developed mutations resistant to entecavir. All five patients tested positive for HBeAg and had HBV DNA levels greater than 6 log10 copies/mL at baseline.
“Long-term treatment of treatment-naive CHB patients with 0.5 mg/day entecavir for 4 years suppressed HBV DNA to undetectable levels in more than 90% of patients, regardless of HBeAg status and genotype,” the researchers concluded. “Moreover, the drug was very safe and rarely induced resistance mutations. Further studies exploring the therapeutic efficacy over longer durations may be necessary to confirm these findings.”