Intention-to-treat outcomes of patients with hepatocellular carcinoma receiving immunotherapy before liver transplant: The multicenter VITALITY study

Background & aims: The use of immune checkpoint inhibitors (ICIs) in patients with advanced hepatocellular carcinoma (HCC) has become widespread with encouraging outcomes in the neoadjuvant setting. Safety and intention-to-treat (ITT) outcomes in the peri-transplant setting are currently based on small and heterogenous single-center reports.

Methods: This first multiregional US study (2016-2023) included 117 consecutive patients with HCC assessed for liver transplantation (LT) and treated preoperatively with ICIs. ITT and survival analyses were conducted with evaluation of post-LT rejection rates.

Results: In total, 86 (73.5%) patients exceeded Milan criteria (MC) and 65 (75.6%) were successfully downstaged within a median of 5.6 months; 43 (36.7%) underwent transplantation, including 18 (15.4%) within MC and 23 (19.7%) who were initially beyond but were downstaged. Overall, 94% of the cohort received concurrent ICIs and locoregional therapies. No grade 4-5 adverse events occurred on the waiting list. The 3-year cumulative probability of dropout was 28% for those within MC and 48% for those beyond. Independent predictors of dropout included being beyond MC (p <0.001), alpha-fetoprotein doubling from baseline (p = 0.014) and radiographic responses (p <0.001). The 3-year ITT survival rate was 71.1% (73.5% within MC vs. 69.7% beyond MC, p = 0.329), with a 3-year post-LT survival rate of 85%. Post-LT rejection occurred in seven patients, six received their last dose of ICI less than 3 months prior to LT, resulting in one graft loss.

Conclusions: The first multicenter evaluation of patients with HCC receiving ICIs pre-LT demonstrates favorable survival and safety outcomes, justifying continued utilization and further evaluation of this strategy in clinical practice. High tumor burden, doubling of alpha-fetoprotein levels, and radiographic response were identified as predictors of unfavorable oncologic outcomes.

Impact and implications: Herein, we report results from the first multicenter evaluation of pretransplant immune checkpoint inhibitors in hepatocellular carcinoma to show promising intention-to-treat survival, safety and rejection rates. Immune checkpoint inhibitors, either alone or combined with locoregional therapy, demonstrate reliable efficacy. This preoperative strategy could be particularly beneficial for high-risk patients, including those requiring downstaging or with elevated alpha-fetoprotein levels despite locoregional treatment. These findings fill current knowledge gaps and offer reassuring evidence for the feasibility of pretransplant use of immune checkpoint inhibitors, pending results from ongoing trials.