Precision BioSciences Inc. (NASDAQ: DTIL) announced clinical trial data showing its experimental hepatitis B treatment PBGENE-HBV eliminated viral DNA in liver tissue and achieved complete loss of a key biomarker in all treated patients.

The data was presented at the European Association for the Study of the Liver Congress. According to the company, liver biopsy analysis demonstrated a 10-fold reduction in covalently closed circular DNA (cccDNA) transcripts after two doses of PBGENE-HBV at 0.4 mg/kg. The treatment also inactivated remaining viral DNA through genetic modifications.

In the ELIMINATE-B study, 38 doses were administered to 16 patients across five treatment groups as of May 4. The company reported that 100% of patients with detectable pregenomic RNA (pgRNA) at baseline achieved complete loss of this biomarker. All 15 evaluable patients experienced substantial declines in hepatitis B surface antigen levels.

The treatment showed safety concerns including infusion-related reactions and reversible liver enzyme elevations. One patient in the highest dose group experienced two serious adverse events after the second administration, with one event considered treatment-related. The company implemented mitigation measures including slower infusion rates.

PBGENE-HBV uses gene editing technology designed to target cccDNA, which the company describes as the root cause of chronic hepatitis B infection. The treatment has received Fast Track designation from the FDA.

Man Fung Yuen, a study investigator at The University of Hong Kong, presented the data at the conference. The company plans to expand enrollment and expects to provide additional trial updates by the end of 2026.