Purpose: Child-Turcotte-Pugh class A (CTP-A) in unresectable hepatocellular carcinoma (HCC) is the standard criterion for active therapy and clinical trial enrollment. We hypothesized that insulin-like growth factor-1 (IGF-1) derived scores may provide improved survival prediction over CTP classification. This study aimed to evaluate the potential prognostic and predictive effects of IGF-1 derived scores in the phase III IMbrave150 study.
Patients and methods: Baseline and on-treatment serum IGF-1 levels from 371 patients were subjected to central analysis. Patients' IGF-1 score (1/2/3) and IGF-CTP score (A/B/C) were determined based on pre-specified cutoffs. Outcomes were analyzed by baseline and by on-treatment changes of the IGF-1 and IGF-CTP scores within and between the two treatment arms. The interaction between these scores and outcomes was assessed using univariate and multivariate analyses.
Results: Baseline IGF-CTP score (A vs B/C) showed prognostic significance for OS in both the atezolizumab-bevacizumab (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.20-0.56; P<0.001) and sorafenib (HR, 0.32; 95% CI, 0.16-0.65; P=0.002) arms. Baseline IGF-1 score (1 vs 2/3) also showed prognostic significance for OS in both the atezolizumab-bevacizumab (HR, 0.33; 95% CI, 0.20-0.55; P<0.001) and sorafenib (HR, 0.48; 95% CI, 0.26-0.89; P=0.02) arms. HRs for PFS were consistent with those for OS. No significant predictive effects were observed for either score between the two arms. Kinetic analysis revealed that patients with increased IGF-1 score (1-> 2/3) at 3 weeks post treatment had shorter OS than patients with stable IGF-1 score of 1 in both the atezolizumab-bevacizumab (HR, 3.70; 95% CI, 1.56-8.77; P=0.003) and sorafenib (HR, 5.83; 95% CI, 1.88-18.12; P=0.0023) arms.
Conclusion: Baseline and kinetic change of IGF-CTP and IGF-1 scores are independent prognostic factors for patients with unresectable HCC treated with atezolizumab-bevacizumab or sorafenib. These novel scores may provide improved patient stratification in future HCC clinical trials. IMbrave150 ClincialTrials.gov number, NCT03434379.
Keywords: HCC; IGF-CTP score; immunotherapy; prognostic biomarker.
© 2022 Kaseb et al.