Adjuvant immunotherapy with autologous cytokine-induced killer cells for hepatocellular carcinoma

Background & Aims No adjuvant therapy has been shown to extend the survival of patients with hepatocellular carcinoma (HCC) receiving curative treatment. We investigated whether injections of activated cytokine-induced killer (CIK) cells (CD3+/CD56+ and CD3+/CD56- T cells and CD3-/CD56+ natural killer cells) prolongs recurrence-free survival of patients after curative therapy for HCC. Methods We performed a multicenter, randomized, open-label, phase 3 trial of the efficacy and safety of adjuvant immunotherapy with activated CIK cells (created by incubation of patients' peripheral blood mononuclear cells with interleukin 2 and an antibody against CD3). The study included 230 patients with HCC treated by surgical resection, radiofrequency ablation, or percutaneous ethanol injection at university-affiliated hospitals in Korea. Patients were assigned randomly to receive immunotherapy (injection of 6.4 × 10⁹ autologous CIK cells, 16 times during 60 weeks) or no adjuvant therapy (controls). The primary end point was recurrence-free survival; secondary end points included overall survival, cancer-specific survival, and safety. Results The median time of recurrence-free survival was 44.0 months in the immunotherapy group and 30.0 months in the control group (hazard ratio with immunotherapy, 0.63; 95% confidence interval [CI], 0.43-0.94; P =.010 by 1-sided log-rank test). Hazard ratios also were lower in the immunotherapy than in the control group for all-cause death (0.21; 95% CI, 0.06-0.75; P =.008) and cancer-related death (0.19; 95% CI, 0.04-0.87; P =.02). A significantly higher proportion of patients in the immunotherapy group than in the control group had an adverse event (62% vs 41%; P =.002), but the proportion of patients with serious adverse events did not differ significantly between groups (7.8% vs 3.5%; P =.15). Conclusions In patients who underwent curative treatment for HCC, adjuvant immunotherapy with activated CIK cells increased recurrence-free and overall survival. ClinicalTrials.gov number: NCT00699816.