Swedish biotech company Medivir has dosed the first subject in a Phase Ib study evaluating MIV-818, a pro-drug designed to selectively treat liver cancers and reduce side effects.

MIV-818 is a liver-directed nucleotide prodrug of troxacitabine. It has been developed as an orally administered therapeutic and has a high level of anti-tumour activity that is targeted to the liver.

The drug has the potential to become the first liver-directed, orally administered drug to benefit patients with advanced hepatocellular carcinoma (HCC) and other forms of liver cancer, such as intrahepatic cholangiocarcinoma.

The MIV-818 Phase I study (NCT03781934) comprises the already completed Phase Ia, which was a within-patient dose-escalation study.

It also consists of the Phase Ib part between-patient dose-escalation study, a classic 3+3 dose-escalation multi-centre study in patients with advanced liver cancer.

According to the data from Phase Ia of the study, five out of nine patients were considered to have stable liver disease after MIV-818 treatment. It demonstrated a liver-cancer directed effect of the drug.

The company stated that Phase Ib of MIV-818 is intended to identify the recommended Phase II dose.

The safety and tolerability profile of the drug is the primary objective of this phase. A secondary objective is to further explore its efficacy.

Medivir CEO Dr Uli Hacksell said: “Patients with advanced liver cancer have limited treatment options and the unmet medical need is large.

“Having obtained an encouraging proof-of-concept for the liver-cancer directed effect of MIV-818 in Phase Ia, we hope to get additional supportive data from the Phase Ib study. We believe that MIV-818 has the potential to provide liver cancer patients with major therapeutic benefits.”