Bristol-Myers Squibb Company announced data from a four-year cohort, which showed that 91 per cent (98/108) of patients treated with Baraclude (entecavir) suppressed the amount of hepatitis B virus in the blood, or viral load, to undetectable levels at week 192.
Suppression of viral load to undetectable levels is a measure of antiviral treatment response; maintenance of viral load suppression is an important goal of chronic hepatitis B treatment. The results are being presented at the 58th Annual Meeting of the American Association for the Study of Liver Diseases (AASLD).
Patients in this cohort were nucleoside naïve e-antigen (HBeAg)-positive patients with chronic hepatitis B infection. HBeAg is a viral protein identified as a marker of active replication of the hepatitis B virus. Patients in this cohort were initially treated with Baraclude 0.5 mg in study ETV-022 and continued treatment with Baraclude 1 mg by enrolling in study ETV- 901 with a less than or equal to 35 day treatment gap.
Resistance monitoring in this cohort identified one patient with genotypic resistance to Baraclude at week 139 who had a virologic breakthrough at week 148.
"The data indicate that Baraclude maintained viral suppression through four years of treatment in this patient population," said Hugo Cheinquer, M.D., Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil. "That a majority of Baraclude patients had undetectable viral load at four years with one patient developing resistance is very encouraging news for physicians who treat this chronic disease."
Safety events in this cohort were consistent with prior experience. Five deaths were reported in this cohort; no deaths were attributed to Baraclude (entecavir). Twelve per cent of patients experienced a serious adverse event. The most common adverse events occurring in greater than or equal to 10 per cent of patients were: upper respiratory tract infection (31 per cent), headache (21 per cent), cough (17 per cent), diarrhoea (16 per cent), influenza (17 per cent), nasopharyngitis (16 per cent), pyrexia (12 per cent) and upper abdominal pain (10 per cent).
This four-year cohort evaluated long-term efficacy and safety of Baraclude in nucleoside-naïve chronic HBeAg-positive patients who received four years of continued Baraclude treatment. The four-year cohort consisted of 146 patients.
The analysis cohort was defined regardless of treatment response at the end of dosing in study ETV-022 or viral load, HBV serology, or ALT measurements at the start of dosing in study ETV-901. Serologic testing was conducted by a central laboratory in study ETV-022 and by local laboratories in study ETV-901.
At week 192 of Baraclude (entecavir) treatment, 91 per cent of nucleoside-naïve chronic HBeAg-positive patients in the cohort achieved undetectable viral load and 86 per cent of patients achieved ALT normalization (ALT less than or equal to 1 times the upper limit of normal).
During years three and four, an additional 41 per cent of patients lost HBeAg and 16 per cent of patients achieved HBeAg seroconversion. Resistance monitoring in this cohort identified one patient with genotypic resistance to Baraclude who later experienced virologic breakthrough.
Ninety per cent of patients had any adverse event whereas grade 3-4 adverse events. Less than one percent of patients experienced on-treatment ALT flares during the fourth year, the company said.
Discovered at Bristol-Myers Squibb, Baraclude is a nucleoside analogue indicated for the treatment of chronic hepatitis B virus infection in adults with evidence of active viral replication with either evidence of persistent elevations in serum aminotransferases (ALT or AST) or histologically active disease. In addition to the United States, Baraclude has been approved in more than 60 countries and regions around the world.
Bristol-Myers Squibb is a global pharmaceutical and related health care products company whose mission is to extend and enhance human life.