Arbutus Biopharma (NASDAQ:ABUS) reported new results from the ongoing Phase 2 study of ARB-1467 in chronically infected HBV patients on stable nucleoside therapy, and plans to add a fourth cohort of patients to the trial.
Multiple dose results from cohort 2 showed a significant reduction in HBsAg, or hepatitis B surface antigen, an indication of HBV infection. In both cohort 1 and cohort 2, an additive, step-wise reduction in HBsAg was observed with each dose.
In addition, the HBsAg reduction achieved after three monthly doses of 0.4mg/kg in cohort 2 was greater than that seen at 0.2 mg/kg in cohort 1, demonstrating a dose-response seen with repeat dosing. The company plans to add another cohort to this study to explore bi-weekly administration of the 0.4 mg/kg dose.
“We are very encouraged by these promising results from the ongoing Phase 2 study of ARB-1467 which, as expected, showed a greater reduction in HBsAg with three monthly doses of 0.4 mg/kg of ARB-1467 than was seen with 0.2 mg/kg of ARB-1467,” Dr. Mark Murray, president and CEO, said in a statement.
“We are excited by the possibility for yet greater HBsAg reductions with additional doses,” he added. “To that end, we have submitted an amendment to add a fourth cohort to evaluate bi-weekly dosing of ARB-1467 over a three-month period. We expect to have results from cohort 4 in the second half of 2017.”