Early alpha‐foetoprotein response associated with treatment efficacy of immune checkpoint inhibitors for advanced hepatocellular carcinoma

Abstract Background Post‐treatment decline in serum alpha‐foetoprotein (AFP) levels has been shown to predict the treatment efficacy of antiangiogenic therapy for advanced hepatocellular carcinoma (HCC). We explored whether a decline in AFP levels was also associated with treatment outcomes of immune checkpoint inhibitors (ICIs) in patients with advanced HCC. Methods We reviewed all patients who received ICI therapy for advanced HCC. AFP response was evaluated in patients with the pretreatment AFP level of >20 ng/mL. We defined early AFP response as a >20% decline in serum AFP levels within the first 4 weeks of treatment initiation relative to pretreatment levels. We then studied whether early AFP response was associated with treatment outcomes. Results Sixty patients were enrolled in this study; 43 of them were evaluable for early AFP response. The objective response rate of early AFP responders was significantly higher than that of early AFP nonresponders (73% vs. 14%, P < .001). Early AFP responders, compared with early AFP nonresponders, exhibited significantly longer overall survival (OS) (median, 28.0 vs 11.2 months, P = .048) and progression‐free survival (PFS) (median, 15.2 vs 2.7 months, P = .002). After adjusting for other clinicopathological variables and treatments, early AFP response remained an independent predictor for longer OS (hazard ratio [HR] = 0.089, 95% confidence interval [CI] = 0.018‐0.441; P = .003) and PFS (HR = 0.128, 95% CI = 0.041‐0.399; P < .001). Conclusion Early AFP response was associated with higher treatment efficacy of ICIs for advanced HCC. Additional validation studies are nonetheless warranted.