Babiker, Hani M.

Abstract Background Optimal treatment following first-line immunotherapy for advanced hepatocellular carcinoma (HCC) remains uncertain. This study evaluated futibatinib, a pan-FGFR inhibitor, combined with pembrolizumab in previously treated patients with FGF19-expressing HCC. Methods Eligible patients were ≥18 years old with advanced HCC, prior systemic therapy, Child-Pugh A-B7 liver function, ECOG 0–2, and FGF19 overexpression. Patients received futibatinib 20 mg orally daily plus pembrolizumab 200 mg intravenously every 3 weeks. The primary endpoint was progression-free survival at 6 months (PFS6). Secondary endpoints included overall survival (OS), objective response rate (ORR), quality of life, and safety. Results Between August 2021 and March 2024, 14 patients enrolled and 13 were evaluable. Median age was 72 years (range, 60–87), 53.8% were male, 92.3% had Child-Pugh A liver function, and all had received prior immunotherapy. Median progression-free survival was 15 weeks (95% CI, 9.0–NE), with a PFS6 rate of 23.1% (95% CI, 8.6–62.3%). ORR was 0% (95% CI, 0–24.7%), while stable disease was observed in 53.9% of patients. Median OS was 55.7 weeks (95% CI, 47.3–NE). Grade ≥3 adverse events occurred in 69.2% of patients, and grade ≥4 adverse events in 15.4%. One grade 5 event (acute-on-chronic kidney injury) was deemed unrelated to treatment. Common adverse events included hyperphosphatemia, fatigue, diarrhea, elevated transaminases, dry eye, nail changes, rash, and oral mucositis. Conclusions Futibatinib plus pembrolizumab demonstrated an acceptable safety profile but did not meet efficacy thresholds supporting further study in FGF19-expressing HCC. Effective post-immunotherapy treatment strategies remain an unmet need.

PURPOSE Deficient mismatch repair/microsatellite instability (dMMR, MSI-H) in biliary tract cancers (BTCs) is observed in 1%-5% of tumors. MSI-H across solid tumors has demonstrated durable response to immune checkpoint inhibitors (ICIs) regardless of the anatomic location. Here, we describe clinical outcomes and surgical conversion of MSI-H BTC treated with ICIs. Patients and Methods We conducted a multicenter, retrospective analysis of BTC patients with dMMR/MSI-H between 2017 and 2024 at Mayo Clinic, University of Michigan, and University Hospitals Seidman Cancer Center. Outcomes of interest were surgical resection rate, rate of pathologic response, 2-year overall survival (OS; time from initiation of treatment to death/last follow-up), and time to treatment discontinuation (TTD; time from initiation of treatment to cessation because of any cause). Analyses were descriptive. RESULTS Thirty patients with MSI-H BTC were identified: 19 with cholangiocarcinoma, three with gallbladder cancer, and 8 with BTC undefined. The median age at diagnosis was 61.5 years (range, 26-86). Twenty-six (86.7%) patients had advanced stage at diagnosis. Twenty-seven patients (90%) received first-line systemic therapy, and 13 (48.1%) continued onto second line. Six patients (23.1%) were restaged to resectable from advanced disease after ICI therapy and underwent resection; all remained recurrence-free at last follow-up. Of these six patients, 3 (50%) achieved a pathologic complete response. Among those receiving first-line therapy, the median TTD was 9.9 months (95% CI, 5.7 to 14.5 months) and the 2-year OS was 73% (95% CI, 56% to 94%). CONCLUSION ICI therapy in patients with MSI-H BTC demonstrated durable response and downstaged some BTC to a resectable stage. dMMR/MSI-H should be performed up-front to guide treatment decisions.

Summary Functional ex vivo assays using live tumor tissues have demonstrated strong predictive accuracy for response to immune checkpoint inhibitors (ICIs) but are not scalable, requiring manual processing of large resections collected at academic centers. Here, an ex vivo live tumor fragment (LTF) platform was developed using standard-of-care biopsies from 228 patients with suspected malignancy collected across prospective, multicenter observational trials and biobanks. Hierarchical clustering of ICI-mediated changes in cytokine production identified two groups: responders and nonresponders. A binary classifier (elive index) using 8 cytokines achieved an AUC of 0.99 for cluster prediction. elive index correctly predicted clinical benefit in 93% (26/28) of patients ( P = 3.2x10 -5 ) and accurately identified 83% (10/12) of objective responders. Critically, elive responders were identified among biomarker-negative patients, highlighting the platform as a scalable approach that complements existing companion diagnostics and expands the population of patients identified to benefit from ICI therapy.

e16435 Background: Peritoneal metastasis in pancreatic ductal adenocarcinoma (PDAC) is historically associated with a dismal prognosis and limited response to systemic therapy alone. The role of locoregional therapy remains controversial. This study evaluated the survival impact and safety of HIPEC, with or without cytoreductive surgery (CRS), compared to standard-of-care systemic therapy in patients with peritoneal metastatic PDAC. Methods: We conducted a comparative analysis of 130 patients with peritoneal metastatic PDAC, comprising a study cohort treated with HIPEC (n = 33) and a control group treated with systemic chemotherapy alone (Non-HIPEC, n = 97). HIPEC patients received induction chemotherapy (predominantly FOLFIRINOX) followed by HIPEC ± CRS. Co-primary endpoints included 12 months survival, and 6 months progression free survival (PFS). Secondary endpoints evaluated Overall Survival (OS ), safety of CRS, and impact of germline mutation status on survival. Study was approved under IRB protocol 25-008762. Results: The 12-month OS rate was significantly higher in the HIPEC group compared to the chemotherapy-only control group (100% vs. 52.6%, P < 0.001). The 6-month PFS rate in the HIPEC group was 63.0% vs. 47.94 in-only control group (P < 0.001). For secondary endpoints, the HIPEC group demonstrated a significantly longer median OS of 33.0 months vs. 17.0 months for controls (P < 0.001). Within the HIPEC cohort, the addition of CRS (n = 25) significantly improved outcomes compared to HIPEC alone (n = 8): median OS improved from 21.5 to 36.0 months (P = 0.03). Germline testing was performed in 61% of HIPEC patients and 48% of controls, identifying pathogenic mutations in 25% and 17%, respectively. Identified pathogenic mutations in both groups included ATM (n = 4), MUTYH (n = 2), BRCA2 (n = 1), CHEK2 (n = 1), PALB2 (n = 1), and KIT (n = 1). In the control group, specific mutations drove divergent outcomes; ATM median OS: 23.5 months vs. MUTYH : 8.0 months (P = 0.04). Conversely, in the HIPEC+CRS cohort, survival was excellent regardless of genetic profile: mutation carriers achieved a median OS of 33.0 months compared to 31.0 months in wild-type patients (P = 0.85). Despite a 34.8% postoperative complication rate in the HIPEC group, there was no perioperative mortality. Conclusions: In selected patients with peritoneal metastatic PDAC, HIPEC provides a substantial survival advantage over systemic therapy alone, achieving a 100% 12-month survival rate and more than doubling the median overall survival. Importantly, germline mutation status did not preclude survival benefit, with mutation carriers deriving equal efficacy from the multimodal approach. These findings support HIPEC+CRS as a highly effective strategy that may overcome adverse biologic drivers.

e16018 Background: Intrahepatic cholangiocarcinoma (iCCA) exhibits marked heterogeneity in outcomes that is incompletely explained by stage or treatment timing. Although treatment delay is frequently cited as a modifiable risk factor, its prognostic significance in real-world practice remains unclear. We applied machine learning (ML) to model iCCA as a dynamic disease process and to evaluate whether longitudinal disease trajectories better explain outcomes than treatment timing alone. Methods: We conducted a population-based retrospective analysis of adults diagnosed with iCCA using the Surveillance, Epidemiology, and End Results (SEER) database (2000–2022). Time from diagnosis to first cancer-directed therapy was categorized as ≤30 days, 31–60 days, or > 60 days. Associations between treatment delay, disease characteristics, and overall survival (OS) were assessed using multivariable logistic and Cox regression models. To capture real-world disease evolution, each patient’s clinical course was encoded as an ordered longitudinal sequence of diagnosis, treatment states (surgery, chemotherapy, radiation), and outcome. Unsupervised ML was used to identify latent disease-course trajectories. A supervised ML model using variables available at diagnosis was developed to predict membership in high-risk trajectories. Results: The cohort included 18,312 patients with iCCA. Treatment initiation beyond 30 days occurred in more than half of patients and was more common in localized than advanced disease. In adjusted survival analyses, shorter time to treatment was paradoxically associated with worse OS, consistent with confounding by disease severity rather than a protective effect of delay. Unsupervised ML identified four distinct and reproducible disease trajectories with markedly different outcomes. Median OS ranged from approximately 2 months in early-failure trajectories to approximately 15 months in favorable multimodality trajectories. Trajectory membership was not fully explained by stage or treatment timing. A supervised ML model predicted high-risk trajectory membership with good discrimination (AUC 0.82). Key predictors included tumor grade, age, tumor burden, and incomplete staging, whereas treatment timing had minimal influence. Conclusions: In iCCA, treatment delay reflects underlying disease biology and care prioritization rather than independently determining survival. ML-based trajectory modeling reveals clinically meaningful disease courses that better explain outcome heterogeneity than treatment timing or stage alone and enables early identification of patients at highest risk for unfavorable real-world outcomes.

4017 Background: First-line mCCA treatment is chemotherapy and immunotherapy. Based on the phase 2 FIGHT-202 trial, pemigatinib was the first FGFR1-3 inhibitor approved in second line and beyond for mCCA with FGFR2 rearrangement. Results from the phase 3, randomized, global FIGHT-302 trial evaluating pemigatinib as first-line therapy are reported here (NCT03656536). Methods: Patients (pts) aged ≥18 y with previously untreated mCCA with FGFR2 rearrangement were randomized 1:1 to receive oral pemigatinib (13.5 mg once daily q21) or intravenous chemotherapy (1000 mg/m 2 gemcitabine + 25 mg/m 2 cisplatin d1,8 q21 ≤8 cycles) stratified by previous receipt of 1 chemotherapy cycle, geographic region, and tumor burden. Pemigatinib crossover was allowed for control arm pts progressing on chemotherapy. Primary end point was progression-free survival (PFS). Secondary efficacy, safety, and exploratory end points were also analyzed. Results: After prescreening >4000 pts, only 196 had FGFR2 rearrangement and were screened; 167 were randomized to receive pemigatinib (n=83) or chemotherapy (n=84) before closing the study early due to slow accrual. Baseline characteristics and demographics were similar between arms. Median PFS (mPFS) with pemigatinib versus chemotherapy was 8.3 versus 6.8 mo, respectively (hazard ratio [95% CI], 0.58 [0.39-0.87]; nominal P =.0078); secondary efficacy endpoints generally supported primary results (Table). Median OS was similar, although these results are confounded by FGFR inhibitor administration as second-line treatment. In the crossover group (n=42, second-line pemigatinib), mPFS was 8.1 mo. Safety was consistent with previous results (Table). Exploratory analyses of genetic co-alterations associated with treatment response will be presented. Conclusions: FIGHT-302 was the first phase 3 trial of a targeted therapy for untreated mCCA. Pemigatinb demonstrated superior activity and prolonged mPFS compared with first-line chemotherapy. The results confirm the current management paradigm of pemigatinib administration after disease progression on chemotherapy. Clinical trial information: NCT03656536 . Pemigatinib Gemcitabine + cisplatin mPFS (95% CI), mo a 8.3 (6.5-12.2) 6.8 (6.1-8.3) Objective response rate, n/N (%) a 39/83 (47) 13/84 (15.5) Median duration of response (95% CI), mo a 14.2 (8.7-24.7) 6.3 (4.3-not estimable) Median overall survival (95% CI) a,b , mo 24.4 (18.6-35.9) 25.0 (18.7-34.2) Treatment related TEAEs, n/N c (%) 80/83 (96) 70/73 (96) Serious TEAEs, n/N (%) c,d 23/83 (28) 17/73 (23) Grade ≥3 TEAEs, n/N (%) c 65/83 (78) 49/73 (67) TEAEs leading to treatment discontinuation, n/N (%) c 5/83 (6) 8/73 (11) Fatal TEAE, n/N (%) c,d 3/83 (4) 0 a All randomized pts. b Interpretation limited by second-line treatment with FGFR inhibitor in gemcitabine + cisplatin arm. c Pts who received ≥1 study dose. d None deemed treatment related.

3146 Background: The MTA-cooperative PRMT5 inhibitor BMS-986504 selectively binds to the PRMT5-MTA complex, a synthetic lethal target in MTAP -del cancer cells, while sparing MTAP –wild-type normal cells. In the phase 1 CA240-0007 study, BMS-986504 was well tolerated and had antitumor activity in pts with MTAP -del advanced solid tumors (ORR, 23%; median DOR, 10.5 mo). BMS-986504 also demonstrated dose-dependent reductions in plasma symmetric dimethylarginine (SDMA) levels, a PD biomarker of PRMT5 inhibition. Here, we report expanded PD and genomic analyses and initial results of exploratory proteomic analyses from CA240-0007. Methods: Pts with advanced, unresectable, or metastatic solid tumors with homozygous MTAP -del received BMS-986504 (50–800 mg) in 3-wk cycles. Analyses of SDMA levels and proteomic profiles from paired plasma samples (baseline and C2D1) were performed using mass spectrometry and SomaScan 11K, respectively. Tumor genomic information was extracted from local pathology reports. ORR was assessed per RECIST v1.1. Results: Among 78 pts with paired samples at data cutoff (22 Sept 2025; median f/u, 15.9 mo), dose-dependent reductions were seen in plasma SDMA levels, with the greatest reductions at 400 mg QD (median, 60.3%; n = 31) and 600 mg QD (median, 60.3%; n = 23). Proteomic pathway enrichment analysis demonstrated downregulation of PI3K/Akt/mTOR, Myc target, cell cycle, and DNA damage repair (DDR) pathways with BMS-986504 on C2D1 (n = 87), consistent with the expected effect of PRMT5 inhibition; a trend toward deeper modulation of PRMT5-regulated pathways was observed at higher doses. No proteins at baseline (n = 94) were found to be significantly associated with ORR (false discovery rate > 0.05). Responses in clinically evaluable pts with NSCLC (n = 33) or PDAC (n = 35) were observed regardless of EGFR , KRAS , or TP53 status. In pts with NSCLC, STK11 and SMARCA4 alterations were numerically higher in nonresponders. No gene alterations were associated with response in PDAC, except GABRA6 alterations (n = 2, both responders). A trend toward higher ORRs was seen in pts with alterations in DDR genes ( CHEK2, FANCD2, XRCC4 , and/or MSH2 ), consistent with the role of PRMT5 in DDR via regulation of mRNA splicing. ctDNA analysis will be presented. Conclusions: BMS-986504 demonstrated robust dose-dependent PD effects in pts with advanced solid tumors in plasma SDMA and proteomic analyses. Downregulation of PRMT5-regulated pathways was observed with BMS-986504 treatment. Response was seen regardless of EGFR, KRAS , and TP53 alterations in NSCLC or PDAC, and DDR gene alterations were associated with improved response. These findings further support the MOA of BMS-986504 and its ongoing investigation in the phase 2/3 MountainTAP-9, -29, and -30 studies as a potential treatment option in pts with MTAP -del advanced solid tumors. Clinical trial information: NCT05245500 .

Tumor Treating Fields (TTFields) represent a novel, non-invasive therapeutic modality in oncology that employs low-intensity, intermediate-frequency alternating electric fields to disrupt mitotic processes and induce cancer cell death. This review integrates mechanistic, preclinical, and emerging clinical evidence supporting the integration of TTFields with immunotherapeutic strategies in pancreatic ductal adenocarcinoma (PDAC). Although immunotherapy has transformed the treatment landscape across multiple malignancies, its efficacy in PDAC remains limited due to the tumor’s dense stroma, immunosuppressive microenvironment, and low immunogenicity. Preclinical investigations suggest that TTFields may potentiate immune-based therapies by enhancing antigen presentation, modulating the tumor microenvironment (TME), and attenuating mechanisms of immune resistance. We highlight studies evaluating TTFields in combination with immune checkpoint inhibitors (ICI), adoptive cellular therapies, and cancer vaccines, emphasizing their potential synergistic effects in PDAC. Clinically, the phase II PANOVA-2 trial demonstrated feasibility and encouraging survival outcomes with TTFields in combination with gemcitabine and nab-paclitaxel, providing the rationale for the ongoing phase III PANOVA-3 trial and the phase II PANOVA-4 trial, which combines TTFields with chemotherapy and atezolizumab. Additional clinical experiences in glioblastoma (GBM) and non-small-cell lung cancer (NSCLC) further substantiate the broader applicability of TTFields as an immunomodulatory adjunct. Remaining challenges include optimizing treatment sequencing, identifying predictive biomarkers, and managing TTFields-associated toxicities. Collectively, current evidence positions TTFields as a promising strategy to augment immunotherapy in PDAC, warranting further translational and clinical investigation to establish its role in reshaping therapeutic paradigms.

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is driven predominantly by oncogenic KRAS signaling and characterized by an immunosuppressive, fibrotic tumor microenvironment that limits therapeutic responses. RMC-6236, a pan-KRAS inhibitor, and ONIOYID, an investigational anti-tumor agent, each demonstrate partial activity in KRAS-mutant cancers. However, their combined therapeutic potential in PDAC remains unexplored. Here, we evaluated the anti-tumor efficacy, survival benefit, and immunomodulatory effects of RMC-6236, ONIOYID and irinotecan alone and dual combinations multiple in vitro and in vivo PDAC models. Methods: In vitro cytotoxicity assays were performed using KPC, PANC-1, AsPC-1, and PANC-02 cell lines. In vivo therapeutic studies were conducted in orthotopic KPC and PANC-1 tumor models. RMC-6236 was administered orally at 10 mg/kg; ONIOYID and irinotecan was administered intravenously at 5 mg/kg. Tumor growth inhibition, survival, collagen deposition, and immune cell infiltration were analyzed. Tumor microenvironment remodeling was quantified via immunohistochemistry for CD8, CD4, collagen I, and fibronectin. Results: The combination of RMC-6236 and ONIOYID elicited potent anti-tumor effects across all evaluated PDAC cell lines, achieving greater than 90% growth inhibition in vitro. In vivo, co-treatment resulted in more than 90% tumor regression in both KPC and PANC-1 xenograft models, markedly surpassing the efficacy of individual monotherapies and other dual-agent controls. Combination therapy significantly extended overall survival and produced sustained suppression of tumor progression. Mechanistic analyses revealed a substantial reduction in collagen and fibronectin deposition within the tumor microenvironment, consistent with attenuation of desmoplasia. Immune profiling demonstrated a robust enhancement of intratumoral CD8+ and CD4+ T-cell infiltration, along with a pronounced decrease in survivin expression. Importantly, no observable systemic toxicity was detected in treated animals. Conclusions: RMC-6236 combined with ONIOYID yields synergistic anti-tumor effects, remodels the fibrotic PDAC microenvironment, enhances T-cell infiltration, and significantly improves survival in aggressive pancreatic tumor models. These findings provide strong rationale for clinical evaluation of RMC-6236-based combination therapies for KRAS driven PDAC. Citation Format: Hari Krishnareddy Rachamala, Fang Wei, Debabrata Mukhopadhyay, Hani M. Babiker. Combined KRAS pathway inhibition and ONIOYID treatment enhances tumor regression, attenuates desmoplasia, and augments T cell infiltration in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5842.

Abstract Background: Early-onset gastrointestinal (GI) cancers are increasing globally, yet the genomic basis for age-related differences across multiple tumor types remains poorly defined. We leveraged AACR Project GENIE v18.0 (N≈34,000 GI tumors) to characterize molecular distinctions by age in colorectal, pancreatic, small bowel, and anal cancers with sufficient early-onset representation. Methods: Clinical and genomic data were extracted and tumors classified into early-onset (&lt;50 years) and late-onset (≥50 years). Mutation frequencies were compared by cancer type and age group, focusing on recurrent drivers, DNA repair, Wnt signaling, RAS/MAPK, chromatin remodeling genes, and targetable alterations. Results: Early-onset colorectal cancer (N=5,724) showed increased Wnt/β-catenin pathway alterations: APC (+4.9%), TCF7L2 (+4.1%), and TP53 (+5.0%), while late-onset tumors (N=15,807) were enriched for BRAF (−5.4%), RNF43 (−1.9%), and GNAS (−1.1%), indicating divergent tumorigenic pathways. Early-onset pancreatic cancer (N=890) exhibited significantly lower frequencies of canonical drivers—KRAS (−24.7%), TP53 (−15.6%), CDKN2A (−6.9%), SMAD4 (−6.0%)—with enrichment of MEN1 (+3.5%), TSC2 (+3.0%), ATRX (+2.0%), DAXX (+1.9%), and CTNNB1 (+2.4%), consistent with fusion-driven, hereditary, and chromatin remodeling biology. Small bowel cancer (N=99) in early-onset patients demonstrated enrichment in DNA damage response and MAPK/RAS genes including BRCA2 (+7.2%), NF1 (+7.4%), FBXW7 (+8.8%), FLT4 (+6.5%), ARAF (+6.4%), and ALK (+5.1%), whereas late-onset tumors (N=538) were enriched for KDR (−5.1%) and MGA (−5.2%). Early-onset anal cancer (N=62) showed elevated MGA (+7.8%), WHSC1/NSD2 (+6.9%), PBRM1 (+6.2%), FANCA (+5.2%), ERCC5 (+6.2%), and MSH6 (+5.9%), highlighting chromatin remodeling and DNA repair pathways potentially related to HPV biology; late-onset tumors (N=464) had enrichment in ATM (−5.6%), PTEN (−5.5%), STK11 (−5.2%), APC (−5.2%), and KMT2C (−5.0%), reflecting age-associated genomic instability. Conclusions: This pan-GI age-stratified analysis reveals distinctive oncogenic programs in early-onset GI cancers characterized by Wnt/TP53-driven colorectal, fusion- and chromatin remodeling-driven pancreatic, DNA damage response/MAPK-driven small bowel, and chromatin-immune DDR signatures in anal cancers. These findings underscore the need for age-tailored precision oncology and support routine genomic profiling in early-onset GI malignancies to identify targetable alterations enriched in younger patients. Citation: AACR Project GENIE Consortium. AACR Project GENIE: Powering Precision Medicine Through an International Consortium. Cancer Discov. 2017;7(8):818-831. (Data: GENIE Release 18.0-public)Acknowledgement: AACR and Project GENIE registry Citation Format: Ahmed Abdelhakeem, Nency Ganatra, Dina Elantably, Tayo Adeoye, Nayef H. Abdel-Razeq, Mosalem M. Osama, Hani M. Babiker. Distinct age associated genomic landscapes in colorectal, pancreatic, small bowel, and anal cancers: A pan gastrointestinal analysis of 34,000 tumors from AACR Project GENIE v18.0 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 4105.