Assembly Biosciences (ASMB) said Wednesday a phase 1b trial of its drug candidate ABI-4334 showed 'strong' antiviral activity in chronic hepatitis B patients.

Two groups of 10 patients with different doses met the safety profile supporting once-daily oral dosing for a 28-day treatment, the company said, adding there were no serious adverse events or adverse events that led to the study drug discontinuation.

Assembly Biosciences also said Gilead Sciences (GILD), under its collaboration with Assembly, may opt for an exclusive license for further development based on the trial's findings.

Shares of the company were up over 1.2% in recent Wednesday premarket activity. Gilead's shares were down 0.1%.