Comparative effectiveness and healthcare utilization of atezolizumab plus bevacizumab versus durvalumab plus tremelimumab in older patients with advanced hepatocellular carcinoma.

e16232 Background: Older adults constitute an increasing proportion of patients with advanced hepatocellular carcinoma (HCC) but remain underrepresented in pivotal clinical trials. Treatment selection in this population is influenced by bleeding risk, frailty, cardiovascular comorbidities, and concerns regarding immune-related toxicity. Although Atezolizumab plus Bevacizumab (AtezoBev) and Durvalumab plus Tremelimumab (DurvaTreme) are established first-line regimens, comparative real-world data in older patients are not well defined. We compared survival, tolerability, and healthcare utilization between these regimens in patients aged ≥65 years. Methods: We conducted a retrospective cohort study using the TriNetX Research Network. Patients aged ≥65 years with advanced HCC who initiated first-line AtezoBev or DurvaTreme were identified. The index date was treatment initiation. The primary outcome was overall survival (OS). Secondary outcomes included hospitalization, emergency department (ED) visits, systemic corticosteroid exposure, and gastrointestinal bleeding. Cohorts were matched 1:1 using propensity scores adjusting for age, sex, and baseline comorbidities. Kaplan–Meier methods and Cox proportional hazards models were used for survival analysis. Results: We identified 4,926 patients treated with AtezoBev and 793 treated with DurvaTreme. After propensity score matching, balanced cohorts of approximately 650 patients per group were analyzed. At 3 months, survival was higher with AtezoBev compared with DurvaTreme (84.7% vs 78.4%; HR 0.67, 95% CI 0.51–0.87, p < 0.01). No significant difference in long-term OS was observed (HR 0.95, 95% CI 0.80–1.13; p = 0.55). Hospitalization occurred in 41.3% versus 38.0% (RR 1.09, 95% CI 0.83–1.43; p = 0.56). ED visits occurred in 13.4% versus 15.7% (RR 0.86, 95% CI 0.61–1.21; p = 0.37). Systemic corticosteroid exposure within 1 year was higher with DurvaTreme (50.0% vs 38.5%; p < 0.01). Conclusions: Among older adults with advanced HCC, AtezoBev and DurvaTreme demonstrated comparable long-term survival in real-world practice. AtezoBev demonstrated improved early survival and numerically lower ED utilization, whereas DurvaTreme was associated with higher corticosteroid exposure. These findings highlight the importance of individualized treatment selection in older patients, incorporating clinical risk factors, toxicity profiles, and patient preferences. Limitations include the retrospective design, potential residual confounding despite matching, and limited detail in electronic health record data.