PRKACA and hepatocellular carcinoma: The FusionVAC22_01 trial is a phase I, open-label, multi-center clinical trial designed to evaluate the safety, tolerability and preliminary efficacy of a DNAJB1-PRKACA fusion transcript-based peptide vaccine Fusion-VAC-XS15, in combination with anti-PD-L1 immune checkpoint inhibition with the PD-L1 antibody atezolizumab in patients with FL-HCC or other cancer entities carrying the DNAJB1-PRKACA fusion transcript.