Borad, Mitesh J.

Abstract Background Unresectable hepatocellular carcinoma (uHCC) is a leading cause of cancer death. FDA-approved first-line systemic therapies include atezolizumab/bevacizumab (atezo/bev) and durvalumab/tremelimumab (durva/treme); however, there is a lack of comparative data. Methods We reviewed outcomes of patients with uHCC who initiated atezo/bev or durva/treme between 2017 and 2024, across six institutions. Overall survival (OS) and time to treatment discontinuation (TTD) were analyzed using the Kaplan–Meier and Cox models, adjusting for baseline characteristics. Results Four hundred fifty-two uHCC pts were included. Median age: 68 years; 77% male; 81% white. Most common etiologies were viral hepatitis (38.9%) and metabolic dysfunction-associated steatohepatitis (19.5%). Disease progression was the primary reason for treatment discontinuation, atezo/bev (56%) and durva/treme (42%). Outcomes were not statistically significant (median OS [month, m]: 14.0 vs 14.6 [P = .66]; median TTD [m]: 4.9 vs 3.9 [P = .42] for atezo/bev vs durva/treme). Outcomes were significantly different between Child-Pugh classes (CP: A, B7, B8/9, C) respectively, median OS(m): 19.0, 6.1, 5.1, 2.0 (P < .001); median TTD(m): 6.1, 2.3, 3.0, 1.3 (P < .001). Conclusions In this real-world study of uHCC, no significant difference in clinical outcomes was observed between atezo/bev and durva/treme in the first-line setting. CP scores were a key prognostic variable with both regimens.

Importance The prognosis of advanced pancreaticobiliary tumors is poor. Next-generation sequencing (NGS) of tissue samples is utilized to identify actionable alterations, but there are occasional limitations due to inadequate tissue acquisition. Circulating tumor DNA (ctDNA) is an alternative method, but its correlation with tissue-based NGS remains unexplored. Objectives To assess the mutation concordance (mCR) rates between ctDNA and tissue testing for patients with pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CC) and to evaluate how ctDNA performs as a treatment response biomarker. Design, Setting, and Participants This retrospective cohort study was conducted among patients with PDAC and CC treated at academic institutions from January 2014 to January 2025. Patients underwent ctDNA testing using 1 platform and tissue NGS testing using 2 platforms. Main Outcomes and Measures mCR, which measures the shared gene alterations observed by both ctDNA and tissue-based NGS testing, was calculated using the Spearman correlation for PDAC and CC. The performance of ctDNA as a treatment response biomarker was assessed by comparing serial ctDNA data with restaging scans and cancer antigen 19-9 levels in patients with PDAC. Results Our cohort included 790 patients: 570 with advanced PDAC (265 [46.5%] female; median [IQR] age, 64 [33-84] years) and 220 with advanced CC (95 [43.2%] female; median [IQR] age, 66 [42-88] years). Overall, 461 patients with PDAC (80.9%) and 192 patients with CC (87.2%) underwent ctDNA testing, while 239 patients with PDAC (41.9%) and 70 patients with CC (31.8%) had tissue NGS testing. Among patients with PDAC, 85 of 130 patients (65.4%) showed shared specific gene alterations between ctDNA and tissue testing; there was a significant mCR, with a Spearman correlation of 0.47 (95% CI, 0.28-0.62; P < .001). For patients with CC, 32 of 48 (66.7%) had shared alterations between ctDNA and tissue testing; there was a significant mCR, with a Spearman correlation of 0.56 (95% CI, 0.35-0.70; P < .001). A subgroup analysis of patients with PDAC who underwent serial ctDNA testing suggested that new TP53 subclones and increased ctDNA variant allele frequency levels of TP53 and KRAS were associated with higher odds of progressive disease (eg, increased TP53 frequency: odds ratio, 7.28; 95% CI, 2.15-24.66; P = .001). Conclusions and Relevance In this cohort study of patients with pancreaticobiliary tumors, there was a significant mCR between ctDNA and tissue NGS testing. Additionally, results suggest that ctDNA might detect resistant clones and enable assessment of treatment response.

This cross-sectional study examines the lawsuits that followed national and international policies for pembrolizumab approval.

Abstract Purpose: TRK-950 is a first-in-class humanized antibody targeting cytoplasmic activation/proliferation-associated protein-1, which is strongly expressed on the cell membrane surface in or on most solid tumors but not in or on normal tissues. This first-in-human study investigated the safety profile, pharmacokinetics (PK), and preliminary antitumor activity. Patients and Methods: Patients with treatment-refractory, locally advanced, or metastatic solid tumors were enrolled in a dose escalation/expansion study. TRK-950 was administered intravenously weekly for 3 weeks in a 28-day cycle, with doses ranging from 3 to 30 mg/kg. Dose expansion included 10 mg/kg weekly and 30 mg/kg biweekly for colorectal cancer and 10 mg/kg weekly for cholangiocarcinoma. The primary objective of this study was to determine its safety, tolerability, and maximum tolerated dose. The secondary objectives were PK, preliminary antitumor activity, and identification of potential biomarkers. Results: Thirty-six patients received at least one dose of TRK-950. In the dose escalation cohort, the maximum tolerated dose was not reached, and no dose-limiting toxicities were observed up to 30 mg/kg. Common adverse events included abdominal pain, fatigue, constipation, back pain, nausea, and decreased appetite. TRK-950 exhibited a PK profile similar to that of other IgG subclass 1 therapeutic antibodies, with linear PK parameters over the 3 to 30 mg/kg dose range. The best response was stable disease. Notably, one patient with cholangiocarcinoma showed signs of cavitation after approximately 8 months, suggesting potential antitumor activity. Conclusions: TRK-950 is safe and well tolerated, has a favorable PK profile, and should be further investigated as a monotherapy and in combination with standard treatment for various types of solid tumors. Significance: TRK-950, a humanized antibody targeting CAPRIN-1, demonstrated good tolerability, no dose-limiting toxicities, a favorable PK profile, and potential antitumor activity in this first-in-human study. Currently, TRK-950 is undergoing Phase Ib and II trials for various cancers, showing promising development potential.

e23011 Background: Eligibility criteria for clinical trials are crucial for maintaining safety and study integrity. However, they often exclude patients due to medical conditions that are not relevant, leading to gaps in understanding the real-world effectiveness of treatments. Addressing potentially modifiable exclusions (PMEs) could enhance accessibility and participation in trials without compromising safety, particularly given the low rates of enrollment. Methods: We retrospectively analyzed ‘screen-failed’ patients (those who were excluded after providing consent because they did not meet the eligibility criteria or other protocol requirements) with biliary tract (BTC) or pancreatic cancer (PDAC) between August 2019 and November 2024. Screening logs and electronic health records provided clinical data. PMEs were identified and validated by two independent medical oncologists. Results: Of 585 screen-failed patients from 18 trials, 76 were excluded due to incomplete data. Among the 509 patients analyzed (367-PDAC, 142-BTC), the leading causes of screen failure were declined participation (99, 19%), comorbidities (59, 12%), suboptimal organ function (56, 11%), absence of biomarker (49, 10%), and insufficient biospecimens (36, 7%). Among patients declining participation, reasons included preference for standard care (23%), travel (22%), competing trials (5%), adverse event concerns (4%), financial issues (3%), and unknown reasons (43%). Of the 509 patients deemed ineligible for study entry at screening, we identified 69 patients (13.6%) with PMEs, primarily related to borderline laboratory abnormalities: liver function (16, 23%), kidney function (14, 20%), platelet count (8, 12%), hemoglobin (5, 7%), and white blood cell count (4, 6%). Other PMEs included previous or concurrent malignancies (6, 9%) and viral hepatitis (3, 4%). PMEs were evenly distributed across trials. Notably, all screen-failed patients proceeded to receive standard therapy. Conclusions: This analysis underscores the potential for rigid eligibility criteria to exclude stable patients who might benefit from investigational treatments. Easing specific criteria, particularly those related to laboratory abnormalities, could broaden trial accessibility. Furthermore, examining the reasons for declined participation and addressing PMEs could help develop strategies to enhance trial enrollment.

e16265 Background: The pivotal TOPAZ-1 trial established durvalumab plus gemcitabine and cisplatin (GC) as a new first-line standard of care for advanced biliary tract cancer (ABTC). However, weekly administration of GC can lead to significant toxicity limiting its tolerability in clinical practice. Based on previous studies, we implemented biweekly regimen of GC on days 1 and 15 together with durvalumab on day 1 of each 28-day cycle to optimize the treatment delivery and improve tolerability. Here, we report the Mayo Clinic experience with biweekly GC with monthly durvalumab in patients with ABTC. Methods: At our three-site institution, we retrospectively identified patients with ABTC between January 2021 and August 2024, who received biweekly GC with monthly durvalumab. Patient demographics, tumor characteristics, treatment details - treatment related adverse events (trAEs) graded according to the NCTCAE V5.0 were collected. Outcomes included median progression-free survival (mPFS), median overall survival (mOS) and clinically assessed overall response rate (ORR) and disease control rate (DCR). Results: 57 patients were included in our analysis, median age was 68 years (range 35-90), and 57.9% were females. 91.2% of patients had ECOG performance status of 0-1. 71.9% had intrahepatic cholangiocarcinoma, 19.3% extrahepatic cholangiocarcinoma and 8.7% gallbladder carcinoma. 70.2% had metastatic disease, 21 % locally advanced unresectable disease and 8.7% recurrent metastatic disease. Patients were followed for a median of 9.1 months (2.3-28.5). 91.2% of the patients received biweekly GC plus monthly durvalumab while 8.8% switched from weekly to biweekly GC plus monthly durvalumab due to treatment toxicities. Median number of treatment cycles was 5. Maintenance regimens included durvalumab (19.3%), gemcitabine/durvalumab (8.8%) and GC/durvalumab (8.8%). Median duration of follow up was 9.1 months (range 2.3 – 28.5). ORR was 36.9% and DCR was 72% (complete response 5.3%, partial response 31.6% and stable disease 35.1%). mPFS was 7.2 months, while mOS was 16 months. Grade(G) 3 or 4 trAEs included abnormal liver function tests (15.7%), infections (11.5%), anemia (8.7%), thrombocytopenia (5.2%), peripheral neuropathy (1.7%), acute kidney injury (1.7%). Immune-related AEs were noted in 6 patients (10.5%) including colitis, gastritis, hepatitis, myocarditis and hypothyroidism. There was no patient with severe neutropenia or febrile neutropenia. Only 5 patients (8.8%) stopped treatment due to trAEs. Conclusions: Biweekly GC on days 1 and 15 plus durvalumab on day 1 of each 28-day cycle is associated with a more favorable toxicity profile while maintaining efficacy similar to that observed in the TOPAZ-1 trial indicating that a de-escalation strategy is feasible with improvement in patient centered outcomes.

4085 Background: Cholangiocarcinoma (CC) is a rare disease with an increasing incidence among younger adults, which is poorly understood. Genomic profiling of tumors is both prognostic and predictive of benefit for targeted therapies. We investigated if there are clinical and molecular differences between younger vs older patients with CC. Methods: We collected TEMPUS genetic data via retrospective chart review from tumors in young vs old patients seen at our institution, defined as ≤50 vs > 50 years of age at time of diagnosis. We included patients diagnosed with CC between January 2008 and July 2024 with available clinical follow up and TEMPUS genetic sequencing data. We collected mutation data on the following actionable genes: FGFR2, IDH1/2, BRCA1, BRCA2, BRAF, ATM, ERBB2/3, and KRAS. Patient characteristics and gene expression variables were compared using Chi-square, Fisher’s exact and Wilcoxon rank-sum tests. Kaplan-Meier, log rank tests and a multivariable Cox model were used for survival analysis. This study was IRB exempt. Results: We included 410 patients, 84 in the young group with median age at diagnosis of 40.8 years, and 326 in the old group with median age 68.5 years. 91.5% of patients were white. There was no difference in BMI between groups, however the older group had higher rates of hypertension (15.5% vs 57.7%), hyperlipidemia (6.0% vs 49.7%), cardiovascular disease (1.2% vs 20.6%), and type 2 diabetes (6.0% vs 21.5%), (all p < 0.01). Primary sclerosing cholangitis was more common in the young group (26.2% vs 4.3%, p < 0.01). ECOG status of 0 at first treatment was seen in 65.3% of young vs 52.5% of old patients (p = 0.02). FGFR2 alterations were more common in the young group (17.9% vs 8.0%, p < 0.01), while ATM mutations were more common in old vs young (5.5% vs 0%, p = 0.03). There was no age difference seen for the other genetic alterations. Mean tumor mutational burden was higher in the old group (4.1 vs 3.8 mut/mb, p = 0.01). MSI-high was found in 2% of cases with no difference between groups. There was no significant difference in overall survival between age groups. There was a numeric difference in overall survival in stage IV patients, though not statistically significant (17.8 months vs. 16.3 months, p = 0.08). In a multivariable Cox analysis, female sex, earlier stage at diagnosis and clinical trial enrollment were associated with favorable prognostics. Conclusions: Our data highlight relatively low rates of comorbidities associated with metabolic dysfunction in younger adults with CC, suggesting alternative factors are likely to explain the increasing incidence of early-onset disease. FGRFR2 is a more common pathogenic alteration among the young and could inform targeted therapies. Younger patients with CC may not have improved survival outcomes compared to their older counterparts. This underscores the aggressive nature of CC and the need for more effective therapies to improve outcomes.

4166 Background: GN is a front-line therapy for aPDAC. A Phase I/II study demonstrated that GCN has a higher overall response rate and median overall survival (mOS). Our previous study found no difference in outcomes among patients with DNA damage repair gene mutations; however, stromal gene expression correlated with mOS in patients receiving GCN. Here, we further evaluate differences in the outcomes with GCN and GN by site of biopsy. Methods: PDAC samples (n = 4,463) were analyzed by NGS (NextSeq/NovaSeq) or RNA (NovaSeq) (Caris Life Sciences, Phx, AZ). Expression of stromal and related genes ( ACTA2, ADIRF, HAS2, IL-6, MMP-2, MMP-9, SPARC, STAT3, TBGB1, TGFB2, TGFBR3, IDO1, HLA-DRB4, VEGFB) from different biopsy sites [high expression (H) >50% of RNA transcripts per million] was correlated with outcomes to GCN or GN. mOS was obtained from insurance claims and calculated from first treatment to last contact. The hazard ratio (HR) was calculated by the Cox proportional hazards model, and p-values were calculated using the log-rank test. Results: 4325 patients [primary biopsy (PT), n = 1,878; non-liver metastatic biopsy (N-LM), n = 818; Liver biopsy (LM), n = 1,629] received GN while 138 patients (PT, n = 45; N-LM, n = 28; LM, n = 65) received GCN. GCN was associated with longer mOS than GN [∆: 5.2 months (m), HR: 0.76, 95% CI 0.63-0.92, p = 0.01]. GCN was associated with longer mOS compared to GN in LM (∆: 5.6 m, HR: 0.66, 95% CI 0.50-0.87, p = 0.003), but it was not significant in PT (∆: 4.6 m, p = 0.13) and N-LM (∆: 4.4 m, p = 0.35). Median MMP2 (38.5 vs. 163.1 vs. 162.2), VEGFB (14.4 vs. 16.9 vs. 16.2) and TGFBR3 (11.4 vs. 15 vs. 16.4) expression were lower in LM compared to PT and N-LM while TGFB1 (41.6 vs. 34.5 vs. 39.8) and IL6 (1.61 vs. 1.19 vs. 1.41) expression were highest in LM (p < 0.05). In LM, IL6 -H (∆: -11 m, p = 0.037) and TGFB1 -H (∆: -5.9 m, p = 0.10) were associated with worse post-GCN survival compared to GN (p = 0.82 and p = 0.57). Whereas, in N-LM, TGFBR3 -H trended towards longer post-GCN survival (∆: 12 m, p = 0.18), while ADIRF -H trended towards shorter post-GCN survival (∆: -12 m, p = 0.056) compared to GN (p = 0.42 and p = 0.10). While in PT, MMP2 -H (∆: 11.3m, HR: 0.46, p = 0.16), TGFB1 -H (∆: 11.3 m, HR: 0.33, p = 0.09), HLA-DRB4 -H (∆: 12.9 m, HR: 0.44, p = 0.11) and VEGFB -H (∆: 10.7, HR: 0.34, p = 0.09) trended towards longer post-GCN survival compared to GN ( MMP2 -H, ∆: 3.4 m, p = 0.03, TGFB1 -H, p = 0.661, HLA-DRB4 -H, p = 0.67, VEGFB-H , ∆: 1.3 m, p = 0.03). Conclusions: GCN is associated with improved mOS compared to GN, especially in LM.Stromal gene expression in the liver differs from that in N-LM and the pancreas. While high stromal gene expression trends towards worse post-GCN survival in LM, it is associated with improved survival in N-LM and PT. Further validation is needed to understand the impact of stromal gene expression in different tumor sites on survival outcomes and signature development.

10587 Background: The American Society of Clinical Oncology (ASCO) and NCCN recommend germline testing for patients (pts) with biliary tract cancers (BTC), particularly those diagnosed at a young age. Prior studies estimate that approximately 15% of pts with BTC harbor pathogenic germline alterations. Germline testing can identify hereditary cancer syndromes, guide targeted therapy, and inform family counseling. This study aimed to further characterize and describe the prevalence of pathogenic germline variants (PGVs) in patients with young-onset BTC (YO-BTC). Methods: We conducted a retrospective review of medical records for pts diagnosed with YO-BTC (ages 18–55) across all Mayo Clinic tri-sites from January 2014 to October 2024. Data collected included results from germline DNA sequencing, tumor genetic testing, demographics, history of other malignancies, and family history of cancer. The primary outcome was the identification of pathogenic germline mutations associated with cancer predisposition. Results: Among 239 pts with YO-BTC, the median age at diagnosis was 43 years (range 19–55), with 62% female and 65.2% identifying as white. Clinical germline testing (e.g., Invitae, Ambry, Myriad) was performed in 123 pts (51.5%), revealing PGVs in 15 pts (12.1%), variants of uncertain significance (VUS) in 30 pts (24.3%), and likely benign variants in 4 pts (3.2%). Among those with PGVs, DNA repair mutations were the most common findings (10/15), including ATM (4), CHEK2 (2), BRCA2 (2), BAP1 (1), and PALB2 (1). One pt had a Lynch syndrome-associated mutation (MSH6), and four had mutations in other cancer-related genes (MUTYH, HOXB13, RMRP, and PIK3CA). Tumor genomic profiling (via CARIS, TEMPUS, or FoundationOne) was performed in 9 pts with PGVs, detecting the variant in 4 (44%), while liquid biopsy (Guardant) identified the PGV in 4 of 6 cases (66.6%).The majority of PGV carriers had advanced BTC (14/15), with intrahepatic cholangiocarcinoma being the most prevalent (11/15), while 4 had extrahepatic cholangiocarcinoma. Additionally, most PGV carriers had a first- or second-degree relative with a prior history of malignancy (14/15), and 3 pts had a second malignancy. Of the 15 pts with PGVs, 4 had BTC associated with primary sclerosing cholangitis. Conclusions: In this large institutional series of YO-BTC, PGVs were identified in 12.1% of pts, demonstrating a significant yield from germline testing in this population. Notably, tissue and liquid biopsies demonstrated different detection rates for PGVs, underscoring the variability in PGVs reporting across platforms. Germline testing through CLIA-approved methods should remain the standard of care. DNA repair pathway mutations, particularly ATM, CHEK2, and BRCA2, were the most frequently identified PGVs, highlighting their role in the pathogenesis of YO-BTC and their potential to guide treatment decisions.