Valerio, Stephen J.

Abstract Background TOPAZ-1 demonstrated durvalumab + gemcitabine and cisplatin (GemCis) superiority over GemCis in first-line treatment of advanced biliary tract cancers. Real-world data from US patients and patients excluded from TOPAZ-1 (patients with autoimmune conditions [AICs] who did not receive immunotherapy) are lacking. We report real-world data for patients with cholangiocarcinoma treated with durvalumab + GemCis. Methods This retrospective, observational study enrolled adult patients diagnosed with cholangiocarcinoma in the US from the International Cholangiocarcinoma Patient Registry (ICPR) treated with first-line durvalumab + GemCis between 2021–2023. De-identified medical records from ICPR were obtained directly from consenting patients/caregivers. Patient demographics and tumor characteristics (primary objective; assessed at initial diagnosis), comorbidities, second-line treatment modalities, median real-world overall survival (mrwOS), and median real-world time to next treatment (mrwTTNT; initiation of first-line treatment and last activity in the database or death) are reported. Results Seventy patients received first-line durvalumab + GemCis: 13 (18.6%) had AIC(s) and 57 (81.4%) did not. Patient demographics, clinical characteristics, and comorbidities are shown (Table). Median (quartile 1–3) time from diagnosis to start of first-line treatment was 1.0 (0.7–1.7) months; median follow-up from first dose of first-line treatment was 7.0 (3.7–12.1) months. The mrwOS (95% CI) was 15.5 (15.1–not evaluable [NE]) months. mrwTTNT (95% CI) was 10.8 (10.4–15.7) months overall and was 20.8 (10.4–NE) months in patients who died without receiving subsequent treatment (censored at date of last activity). Among patients with AIC(s), <5 received second-line therapy (all received chemotherapy alone). Among patients with no AICs, 15 received second-line treatment; 11 (73.3%) received targeted therapy alone and <5 received chemotherapy alone. Conclusions This dataset demonstrates patients with AIC(s) are treated with durvalumab + GemCis in clinical practice. The mrwOS for durvalumab + GemCis in this patient population is consistent with TOPAZ-1 and global real-world studies.

Abstract Background & Objectives Based on the TOPAZ-I study, durvalumab combined with gemcitabine and cisplatin (GemCis) is now supported as a standard of care treatment for cholangiocarcinoma. Patients with extrahepatic cholangiocarcinoma (eCCA) often have underlying autoimmune conditions (AICs) which could restrict immunotherapy use. Treatment patterns in patients with eCCA with AICs and non-autoimmune conditions (NAICs) are reported. Method This retrospective observational analysis of adult patients diagnosed with eCCA in the United States enrolled in the International Cholangiocarcinoma Patient Registry between 2019 and 2023, focused on those treated with durvalumab. The registry contains de-identified data from medical records obtained directly from consenting patients and caregivers. Patients were followed from index date (date of eCCA diagnosis) until the last activity in the database or death. Demographics, clinical characteristics, biomarkers, treatment patterns, and adverse events (AEs) are reported. Results Overall, 135 patients with eCCA were enrolled: 24 (17.8%) had 2:1 AICs and 111 (82.2%) had NAICs. Baseline demographics were comparable between groups: the median (quartile [Q]l-Q3) age at diagnosis was 63.0 (55.0-70.0) years, the mean number of comorbidities in the overall population was 10.1, and 50.4% of patients were female. PD-Ll positivity was noted in 12.6% of patients and HER2 positivity in 10.4%. Of 91 patients with eCCA who received first-line therapy, 34 (37.4%) received GemCis alone, 27 (29.7%) chemotherapy alone (non-GemCis +/- nab-paclitaxel), 9 (9.9%) GemCis plus nab-paclitaxel, 7 (7.7%) durvalumab plus GemCis, 7 (7.7%) durvalumab monotherapy or in combination, and 7 (7.7%) other regimens. Treatment patterns by autoimmune comorbidity status are also reported (Table). Overall, 129 patients (95.6%) had ≥1 AE; fatigue was the most common (71.1%). Conclusion More patients with eCCA received a first-line durvalumab-based regimen post-March 2022 vs the full study period. The use of durvalumab as first-line treatment in this subgroup may suggest that AICs do not restrict its use.

Background: Immunotherapy-based regimens have expanded the treatment landscape for unresectable hepatocellular carcinoma (uHCC); however, real-world data are limited. Methods: This retrospective, observational study used data from electronic medical records from Mayo Clinic sites across the United States. Patients with uHCC who initiated a first-line (1L) systemic therapy between June 2020–October 2022 with ≥2 follow-up visits were included. Treatment patterns, overall survival (OS), and post-index gastrointestinal (GI) bleeding were assessed by GI bleeding risk defined by Child–Pugh Class B or C, pre-index GI bleeding, uncontrolled hypertension, or significant varices and band ligation. Results: Of 186 included patients, 68.8% had GI bleeding risk and 31.2% did not. Atezolizumab plus bevacizumab was the most common 1L systemic therapy in patients with or without GI bleeding risk (72.7% and 29.3%, respectively). Median OS (95% confidence interval) with atezolizumab plus bevacizumab was 12.8 (8.0–19.3) months and not reached in patients with and without GI bleeding risk, respectively. OS rates with atezolizumab plus bevacizumab in patients with or without GI bleeding risk, respectively, were 52.3% and 70.6% at 12 months, 41.6% and 57.8% at 18 months, and 34.6% and 51.3% at 24 months. Post-index GI bleeding with atezolizumab plus bevacizumab occurred in 19.4% and 5.9% of patients with and without GI bleeding risk, respectively. Conclusions: During this study period, atezolizumab + bevacizumab was the most common 1L therapy for patients with uHCC, regardless of GI bleeding risk. OS rates with atezolizumab + bevacizumab were lower in patients with versus without GI bleeding risk. Findings highlight the unmet need for guidance on characteristics-driven treatment decisions.

e16167 Background: Guidelines recommend systemic therapy for uHCC ineligible for locoregional therapy. Until the approval of tremelimumab + durvalumab for uHCC, in Oct 2022, 1L systemic therapies in the US included multikinase inhibitors and atezolizumab (A) + bevacizumab (B). It is crucial to understand factors driving real-world treatment decisions and outcomes in uHCC. Methods: Data were collected from electronic medical records from US Mayo Clinic sites. Pts with uHCC who initiated a 1L systemic therapy between Jun 2020–Oct 2022 (A + B was the only approved 1L immunotherapy (IO)-based regimen) with ≥2 follow-up visits, were included. Index was the date of first 1L systemic therapy. Pts were assessed by risk of post-index gastrointestinal (GI) bleeding (Child-Pugh class B or C, pre-index GI bleeding, uncontrolled hypertension [HTN] [≥2 anti-HTN drugs or ≥2 vital entries of SBP > 140 mmHg or DBP > 90 mmHg]), or significant varices and band ligation). Treatment patterns, overall survival (OS), and post-index GI bleeding were assessed. Results: A total of 186 pts met the inclusion criteria. Most common etiologies of liver disease were MASH (42.7%) and hepatitis C virus (40.2%). Pre-index GI bleeding was reported in 29.0% of pts, of which 46.3% occurred within 6 months (mo) pre-index; 62.4% of pts had EGD, of which 72.4% had varices. There were 128 (68.8%) pts with GI bleeding risk and 58 (31.2%) pts without GI bleeding risk. The most common 1L systemic therapies for pts with GI bleeding risk were A + B (72.7%) and A only (9.4%), while for pts without GI bleeding risk, A + B (29.3%), nivolumab + ipilimumab (13.8%), and B + chemotherapy (12.1%) were the most common. Median OS and OS rates at 12, 18, and 24 mo were lower, and post-index GI bleeding rate was higher in pts with vs without GI bleeding risk (Table). For pts treated with A + B, median OS and OS rates at 12, 18, and 24 mo were lower in pts with vs without GI bleeding risk (Table). Conclusions: In this network, prior to the approval of other 1L IO-based regimens for uHCC, many pts received A + B, despite risk of post-index GI bleeding. Median OS with A + B was shorter in pts with vs without GI bleeding risk. Data highlight the complexity of uHCC and the unmet need for guidance on characteristics-driven treatment decisions. © 2025 American Society of Clinical Oncology, Inc. Reused with permission. This abstract was accepted and previously presented at the 2025 ASCO Gastrointestinal Cancers Symposium. All rights reserved. Table. Full cohort A + B cohort All ptsN=186 GI bleeding risk N=128 No GI bleeding risk N=58 All pts N=110 GI bleeding risk N=93 No GI bleeding risk N=17 Median follow-up, mo 20.6 20.9 20.4 21.3 21.6 20.3 Median OS, mo 14.4 11.4 40.3 13.9 12.8 Not reached OS rates, % 12 mo 55.2 48.9 68.9 55.2 52.3 70.6 18 mo 45.3 38.1 61.1 44.1 41.6 57.8 24 mo 39.4 31.8 56.8 37.1 34.6 51.3 Post-index GI bleed, % 17.2 23.4 3.4 17.3 19.4 5.9

572 Background: Guidelines recommend systemic therapy for uHCC ineligible for locoregional therapy. Until the approval of tremelimumab + durvalumab for uHCC, in Oct 2022, 1L systemic therapies in the US included multikinase inhibitors and atezolizumab (A) + bevacizumab (B). It is crucial to understand factors driving real-world treatment decisions and outcomes in uHCC. Characteristics, treatment patterns, and outcomes were assessed in US pts with uHCC treated with 1L systemic therapy. Methods: Data were collected from electronic medical records from US Mayo Clinic sites. Pts with uHCC who initiated an NCCN-recommended 1L systemic therapy between Jun 2020–Oct 2022 (A + B was the only approved 1L immunotherapy (IO)-based regimen) with ≥2 follow-up visits, were included. Index was the date of first 1L systemic therapy. Pts were assessed by risk of post-index gastrointestinal (GI) bleeding (pts with Child-Pugh class B or C, pre-index GI bleeding, uncontrolled hypertension [HTN] [≥2 anti-HTN drugs or ≥2 vital entries of SBP >140 mmHg or DBP >90 mmHg]), or significant varices and band ligation). Treatment patterns, overall survival (OS), and post-index GI bleeding were assessed. Results: A total of 186 pts met the inclusion criteria. Most common etiologies of liver disease were metabolic dysfunction-associated steatohepatitis (42.7%) and hepatitis C virus (40.2%). Pre-index GI bleeding was reported in 29.0% of pts, of which 46.3% occurred within 6 months (mo) pre-index; 62.4% of pts had EGD, of which 72.4% had varices. There were 128 (68.8%) pts with GI bleeding risk and 58 (31.2%) pts without GI bleeding risk. The most common 1L systemic therapies for pts with GI bleeding risk were A + B (72.7%) and A only (9.4%), while for pts without GI bleeding risk, A + B (29.3%), nivolumab + ipilimumab (13.8%), and B + chemotherapy (13.8%) were the most common. Median OS and OS rates at 12, 18, and 24 mo were lower, and post-index GI bleeding rate was higher in pts with vs without GI bleeding risk (Table). For pts treated with A + B, median OS and OS rates at 12, 18, and 24 mo were lower in pts with vs without GI bleeding risk (Table). Conclusions: In this network, prior to the approval of other 1L IO-based regimens for uHCC, many pts received A + B, despite risk of post-index GI bleeding. Median OS with A + B was shorter in pts with vs without GI bleeding risk. Data highlight the complexity of uHCC and the unmet need for guidance on characteristics-driven treatment decisions. Full cohort A + B cohort All ptsN=186 GI bleeding risk N=128 No GI bleeding risk N=58 All pts N=110 GI bleeding risk N=93 No GI bleeding risk N=17 Median follow-up, mo 20.6 20.9 20.4 21.3 21.6 20.3 Median OS, mo 14.4 11.4 40.3 13.9 12.8 Not reached OS rates, % 12 mo 55.2 48.9 68.9 55.2 52.3 70.6 18 mo 45.3 38.1 61.1 44.1 41.6 57.8 24 mo 39.4 31.8 56.8 37.1 34.6 51.3 Post-index GI bleed, % 17.2 23.4 3.4 17.3 19.4 5.9

Background: Historically, the standard of care for advanced biliary tract cancers (aBTCs) was gemcitabine plus cisplatin (GemCis). Immunotherapy plus GemCis is now recommended as a first-line treatment for aBTCs. Whether patients can tolerate eight cycles of GemCis in clinical practice, as per the Advanced Biliary Cancer (ABC)-02 study, remains to be assessed. We performed a retrospective observational cohort study to assess real-world treatment patterns and overall survival (OS) in patients with de novo or recurrent aBTCs treated with first-line gemcitabine-based chemotherapy in the United States. Methods: This retrospective observational cohort study used Optum’s de-identified Market Clarity Data (Market Clarity). Adults diagnosed with de novo or recurrent aBTCs in the United States who began first-line gemcitabine-based chemotherapy from January 2016–March 2022 were identified and followed from index until death, the end of continuous enrolment, or the end of study period. Treatment patterns and OS were assessed. Results: Overall, 559 patients were included (de novo, n = 462; recurrent, n = 97). GemCis was the most common first-line therapy received (de novo: 73.8%; recurrent: 57.7%). Most patients received approximately five cycles of GemCis; median (95% CI) time to discontinuation was 4.6 (4.3–5.1) months. Most patients died over the follow-up period (de novo: 70.3%; recurrent: 62.9%). Median OS (95% CI) was 14.2 (12.1–16.1) months (de novo) and 18.5 (15.6–26.9) months (recurrent). Conclusions: GemCis was the most common first-line therapy received during the study period; most patients were unable to receive eight cycles of GemCis. Survival was limited over the follow-up period, highlighting the need for new treatments for aBTCs. Future studies are warranted to understand the real-world impact of first-line immunotherapy plus GemCis for patients with aBTCs.

454 Background: Biliary tract cancers (BTC) are often diagnosed at advanced stages (aBTC) when prognosis is poor. In the Phase 3 TOPAZ-1 study (NCT03875235), durvalumab plus gemcitabine and cisplatin (GemCis) significantly improved overall survival versus placebo plus GemCis. To better understand the context of the TOPAZ-1 trial results in the US, we looked at first-line (1L) treatment patterns in participants with aBTC treated with GemCis and other gemcitabine (Gem)-based chemotherapy (CT) regimens. Methods: This retrospective observational cohort study used linked electronic health records and medical and pharmacy claims data from the Optum Market Clarity Database. Adults diagnosed with de novo or recurrent aBTC, who initiated 1L Gem-based CT between January 2016 and March 2022, were identified and followed from the index date (defined as the first administration of Gem-based CT on or after initial BTC diagnosis date) until death, end of continuous enrollment, or end of study period, whichever occurred first. Variables including patient demographics, clinical characteristics, and treatment patterns were described. Results: A total of 580 patients were included in the analysis with either de novo aBTC (n=481, 82.9%) or recurrent aBTC (n=99, 17.1%) with median follow-up time of 10.4 (interquartile range: 6.4, 17.5) and 12.0 (interquartile range: 6.3, 21.9) months, respectively. Mean (SD) age was 64.6 (11.2) and 66.8 (10.4) years, with 45.7% and 54.5% male in the de novo and recurrent aBTC groups, respectively. Most patients were white (77.6%). The most frequent site of primary tumor diagnosis was single-site intrahepatic (overall 62.8%, de novo 66.7%, recurrent 43.4%). In the 12 months prior to index date, 38.5% of patients had biliary obstruction, 30.2% had biliary stents, 29.3% had jaundice, and 17.1% had nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Common comorbidities included cardiovascular disease (50.9%), obesity (46.8%), and diabetes (35.2%). The most common 1L CT was GemCis followed by Gem for both the de novo (n=355, 73.8% and n=36, 7.5%) and recurrent groups (n=58, 58.6% and n=26, 26.3%), respectively. Approximately half of participants (50.9%) switched to a new line of treatment, 33.3% discontinued 1L CT, and 15.9% remained on 1L CT at last follow-up. Most frequent 2L treatments included fluorouracil/oxaliplatin (36.9%) and capecitabine (14.2%). Further analysis will characterize outcomes and regimen duration. Conclusions: Findings from this retrospective study showed that the most common 1L therapies were GemCis and Gem among both de novo and recurrent patients with aBTC. These results provide insight into aBTC treatment practices and may help inform treatment decisions.