Effect of different PD-1 inhibitor combination therapies for unresectable intrahepatic cholangiocarcinoma.

ABSTRACT

BACKGROUND: Immune checkpoint inhibitor (ICI) combination therapy offers a new option for treatment of unresectable intrahepatic cholangiocarcinoma (uICC). AIM: To compare the effect of different anti-PD-1 combination therapies as the first-line treatments for uICC. METHODS: This study included 318 patients who received chemotherapy alone (Chemo), anti-PD-1 plus chemotherapy (ICI-chemo), anti-PD-1 plus targeted therapy (ICI-target) or anti-PD-1 plus targeted therapy and chemotherapy (ICI-target-chemo) as first line for uICC from 22 centres in China. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR) and safety. RESULTS: Patients with ICI-chemo (median PFS [mPFS], 6.3 months; HR 0.61, 95% CI 0.42-0.88; p = 0.008; median OS [mOS], 10.7 months; HR 0.61, 95% CI 0.39-0.94; p = 0.026), ICI-target (7.2 months; HR 0.54, 95% CI 0.36-0.80; p = 0.002; 15.8 months; HR 0.54, 95% CI 0.35-0.84; p = 0.006) or ICI-target-chemo (6.9 months; HR 0.65, 95% CI 0.47-0.90; p = 0.009; 14.4 months; HR 0.47, 95% CI 0.31-0.70; p < 0.001) achieved better clinical outcomes than those with Chemo (3.8 months; 9.3 months). ICI-target was not inferior to ICI-chemo in survival outcomes (HR for PFS 0.88, 95% CI 0.55-1.42; p = 0.614; HR for OS 0.89, 95% CI 0.51-1.55; p = 0.680). ICI-target-chemo yielded similar prognoses as ICI-chemo (HR for PFS 1.07, 95% CI 0.70-1.62; p = 0.764; HR for OS 0.77, 95% CI 0.45-1.31; p = 0.328) and ICI-target (HR for PFS 1.20, 95% CI 0.77-1.88; p = 0.413; HR for OS 0.86, 95% CI 0.51-1.47; p = 0.583) but resulted in more adverse events (p < 0.001; p = 0.010). Multivariable and propensity score analyses supported these findings. CONCLUSIONS: Among patients with uICC, ICI-chemo or ICI-target provided more survival benefits than Chemo while achieving comparable prognoses and fewer adverse events than ICI-target-chemo.