HOOKIPA Pharma has dosed the first patient in a Phase I clinical trial of its investigational, non-replicating arenaviral HB-400 vaccine for the treatment of chronic hepatitis B.

Being developed in partnership with Gilead, HB-400 utilises an alternating two-vector approach to optimise and provide an immune response against the target antigens.

It uses both the lymphocytic choriomeningitis and pichinde viruses with each expressing three highly conserved hepatitis B virus antigens.

The Gilead-led trial intends to evaluate the safety and tolerability of repeated doses of HB-400 in healthy individuals and participants with chronic hepatitis B.

HOOKIPA CEO Joern Aldag said: “Dosing of the first person in the Phase I clinical trial of HB-400 is an important milestone for HOOKIPA, as another programme with our novel arenaviral technology progresses to the clinic.

“More importantly, the start of the HB-400 trial is an important milestone for the hepatitis B community as hepatitis B remains an area of critical unmet need.

“We look forward to working with Gilead to assess the potential impact of our novel arenaviral technology as part of a combination regimen for people living with the disease.”

Under a collaboration and licence agreement signed with Gilead, HOOKIPA received a non-dilutive payment of $5m and is involved in two independent development hepatitis B programmes.

The other programme is aimed at discovering a novel arenaviral vaccine for human immunodeficiency virus (HIV).

Gilead will be solely responsible for further development and marketing of HB-400, referenced as GS-2829 and GS-6779.