Impact of temporary atezolizumab and bevacizumab interruption on survival in advanced HCC: an IMbrave150 analysis

Atezolizumab (Atez) combined with bevacizumab (Bev) is the recommended first-line treatment for unresectable hepatocellular carcinoma (HCC). However, the clinical impact of temporary interruptions of Atez and Bev on treatment outcomes remains unclear.

To evaluate the association between temporary interruptions of Atez or Bev and survival outcomes among patients with unresectable HCC.

Exploratory post hoc analysis of patient-level data from the phase 3 IMbrave150 (NCT03434379) trial.

Global, multicenter, randomized phase 3 trial designed to evaluate the therapeutic benefit of Atez plus Bev compared with sorafenib in patients with unresectable HCC.

A total of 251 patients with unresectable HCC who received Atez and Bev in the IMbrave150 trial.

Temporary interruptions of Atez or Bev during treatment.

Overall survival (OS) and progression-free survival (PFS).

Among 251 patients treated with Atez/Bev, 79 (31.5%) experienced Atez interruptions and 86 (34.3%) had Bev interruptions. Interruptions were not significantly associated with OS (HR = 1.57, 95% CI: 0.90-2.73 for Atez, HR = 0.50, 95% CI: 0.16-1.53 for Bev). However, both were significantly associated with improved PFS (HR = 0.56, 95% CI: 0.34-0.92 for Atez and HR = 0.61, 95% CI: 0.39-0.94 for Bev). Subgroup analyses showed that positive association of PFS and interruptions was primarily observed in patients with events or treatment duration <12 months. Early (within 6 months) and late interruptions (after 6 months) showed trends toward longer PFS but were not statistically significant (HR = 0.56, 95% CI: 0.27-1.15 and HR = 0.57, 95% CI: 0.29-1.09 for Atez, HR = 0.61, 95% CI: 0.37-1.02, and HR = 0.60, 95% CI: 0.29-1.27 for Bev).

In this exploratory analysis, temporary interruptions of Atez or Bev were not associated with worse survival outcomes in patients with unresectable HCC. Prospective studies are needed to validate these findings.