In a Phase 3 trial, a monthly injection combining elebsiran and tobevibart met its primary endpoint in adults with chronic hepatitis delta. At Week 48, 44% of patients receiving the combination had undetectable virus, Vir said.

Nancy Reau, associate director of Solid Organ Transplantation and Section Chief of Hepatology at Rush University Medical Center, said the goal for people with chronic hepatitis delta is not only to reduce the virus but to make it undetectable, because ongoing HDV replication drives liver disease progression. She said the results suggest the combination could provide a meaningful new treatment option.

Vir also reported positive results from an expanded Phase 2 trial. The company said all patients who had completed Week 96 of combination therapy had undetectable viremia, with the treatment producing rapid suppression of HDV RNA.