Al-Rajabi, Raed Moh’d Taiseer

Abstract Background Surgical resection without visible or residual microscopic disease (R0 resection) is known as the optimal path to cure localized pancreatic cancer (PDAC). Neoadjuvant therapy (NAT) is used to improve R0 resection rates; however, the optimal regimen is unclear. We assessed the safety and efficacy of peri-operative gemcitabine/nab-paclitaxel (GEM/NAB) and pre-operative stereotactic body radiotherapy (SBRT) in patients with resectable (R-PDAC) and borderline resectable PDAC (BR-PDAC). Patients and Methods This was a prospective, multicenter single arm phase 2 study in patients with R-PDAC and BR-PDAC. Patients received three cycles of GEM/NAB prior to SBRT followed by surgery and three cycles of adjuvant GEM/NAB. Primary endpoint was R0 surgical resection rate in each cohort. Secondary endpoints included safety and overall survival (OS). Results Eighty-six patients consented and following radiologic screening, 49 were enrolled into two cohorts: R-PDAC (n = 20) and BR-PDAC (n = 29) between June 2016 and April 2021. Seventy percent of R-PDAC (14/20) and 55.2% of BR-PDAC patients (16/29) completed all NAT. Eleven R-PDAC (55.0%) and 11 BR-PDAC patients (37.9%) underwent surgical resection. Nine R-PDAC (45.0%) and 9 BR-PDAC patients (31.0%) had R0 resections. The median OS for R-PDAC and BR-PDAC patients with R0 resections was 22 months (95% CI: 17.7 months-NA) and 39 months (95%CI: 13.21 months-NA), respectively. Conclusion While the trial failed to meet one of its primary objectives as only 45% of R-PDAC patients had an R0 resection, the objective of 30% R0 resection for the BR-PDAC group was met. NAT should be part of current therapeutic strategies for BR-PDAC; however, our trial does not answer what is the best NAT for BR-PDAC. Trial Registration NCT02723331

TPS2675 Background: Checkpoint inhibitor therapy is the standard first-line treatment for advanced/recurrent HCC, but there is a significant unmet therapeutic need for patients (pts) who progress after first-line treatment. Adoptive cellular immunotherapy may provide a novel treatment option. Glypican-3 (GPC3), a heparan sulfate proteoglycan, is overexpressed by tumor cells in HCC and virtually absent in healthy tissues, making it an ideal target for CAR-T therapy. AZD5851 is an autologous CAR-T product that expresses a CAR specific for GPC3 and a dominant negative (dn)TGFβRII as an armoring strategy. Expression of dnTGFβRII can block TGFβ signaling, protecting CAR T-cells from the immunosuppressive effects of this cytokine. Early clinical data with C-CAR031, a CAR-T product with the same GPC3-specific CAR and dnTGFβRII-armoring transgene as AZD5851, showed promising tolerability and antitumor activity in pts with HCC [1]. ATHENA (NCT06084884) is a first-in-human, single-arm, open-label, multicenter phase 1/2 study to evaluate the safety, tolerability, and antitumor activity of AZD5851 in pts with GPC3+ advanced/recurrent HCC, for whom ≥1 prior line of standard therapy failed or was not tolerable. Methods: Eligible pts are aged ≥18 years with histologically confirmed advanced/recurrent or metastatic and/or unresectable HCC, GPC3+ tumor sample as determined by immunohistochemistry, ≥1 prior line of standard systemic therapy, ≥1 measurable lesion per RECIST 1.1, Child-Pugh A, ECOG PS 0/1, and adequate organ and bone marrow function. Approximately 24 pts will be enrolled in Part A (Phase I, dose escalation) and 50 in Part B (Phase II dose expansion). Pts will undergo apheresis to collect peripheral blood mononuclear cells for AZD5851 production, after which they may receive approved bridging therapy for disease control. Upon successful generation of AZD5851 product, pts will undergo lymphodepletion before receiving a single dose of IV AZD5851. Subsequent follow-up is divided into 3 stages: Stage 1, active follow-up of all pts through 6 months post AZD5851 infusion; Stage 2, further evaluation of pts who have not progressed or started a new anticancer regimen during Stage 1; Stage 3, long-term follow-up for all pts who have received AZD5851. The primary endpoints are to assess the safety/tolerability of AZD5851 (both study parts), and to determine the recommended dose(s) of AZD5851 for expansion and phase 2 trials (Part A). Secondary endpoints include efficacy (objective response rate, best overall response, duration of response, disease control rate, durable response rate, time to response, progression-free survival, and overall survival) and pharmacokinetics. Exploratory endpoints include pharmacodynamic biomarkers and immunogenicity. Enrollment began Nov 2023. 1. Zhang et al. AACR 2023. Abstract CT097. Clinical trial information: NCT06084884 .

4175 Background: Patients (pts) with pancreatic adenocarcinoma (PDAC) who are candidates for surgery are anatomically segregated into two groups: those with resectable tumors (R-PDAC), and those with borderline resectable tumors (BR-PDAC). For each group, complete surgical resection with no visible or microscopic disease left behind (R0 resection) is generally accepted as the path to cure. Neoadjuvant therapy (NAT) has been used to improve the R0 resection rate. However, the optimal role and type of NAT that will improve R0 resection rate and overall survival (OS) remains controversial. The Academic Gastrointestinal Cancer Consortium (AGICC) evaluated a perioperative strategy with combination chemotherapy and preoperative stereotactic radiation therapy (SBRT) to improve the R0 resection rate. Methods: This prospective, multicenter open label, single arm phase 2 clinical trial conducted among 5 member AGICC institutions enrolled pts with R-PDAC and BR-PDAC. Treatment included 3 cycles of gemcitabine (1000mg/m2) and nab-paclitaxel (125 mg/m2) (GEM/NAB) on days 1, 8 and 15 of a 28-day cycle prior to SBRT (33Gy: 6.6Gy daily x 5) followed by surgery and 3 cycles of adjuvant GEM/NAB. Accrual goal was 20 R-PDAC and 30 BR-PDAC pts selected by central radiology review. Primary objective was to estimate the R0 resection rate for each cohort. Secondary objectives included safety and tolerability of neoadjuvant treatment and OS. Results: Eighty-six pts signed consent and after radiologic screening, 20 R-PDAC patients and 29 BR-PDAC patients were found eligible to begin treatment. One R-PDAC and two BR-PDAC pts did not initiate therapy. 14 (70%) and 19 (66%) R-PDAC and BR-PDAC pts, respectively, completed all neoadjuvant chemotherapy.14 R-PDAC (70%) and 17 BR-PDAC (59%) pts completed SBRT. 11 R-PDAC pts (55%) and 11 (38%) BR-PDAC, underwent surgery. 8 R-PDAC pts (40%) had an R0 resection. One R-PDAC pt had a complete pathologic response (pCR). 8 BR-PDAC pts (28%) had an R0 resection. 19% (3/16) pts undergoing an R0 resection are alive (47-73+ mos). 16 pts (32%) had at least one grade ≥ 3 non-hematologic adverse event (AE); 25 patients (51%) had at least one grade ≥ 3 hematologic AE. 8 pts, 4 R-PDAC and 4 BR-PDAC were hospitalized prior to surgery. One pt (2%) died during NAT. There were no deaths due to surgery. Conclusions: R0 resection rates and survival in R-PDAC and BR-PDAC were low despite a perioperative approach of systemic therapy and SBRT. The lack of survival benefit of GEM/NAB as an adjuvant regimen, as well as SBRT pre-operatively (both shown in studies subsequent to this one) may explain the disappointing results. While an R0 resection for localized PDAC is recognized as essential, our results demonstrate that an R0 resection is not sufficient to cure the majority of PDAC pts who receive NAT with GEM/NAB + SBRT. Future NAT therapy trials should aim to markedly improve the pCR rates associated with R0 resection. Clinical trial information: NCT02723331 .

4086 Background: Pemigatinib (PEMI), a potent, selective, oral FGFR1-3 inhibitor, has shown efficacy and safety in patients (pts) with CCA and FGFR2 rearrangements/fusions in FIGHT-202 (NCT02924376; objective response rate [ORR], 35.5%; duration of response [DOR], 7.2 months [mo]). Overall survival (OS: 21.1 mo) was not mature in the primary report (Abou-Alfa. Lancet Oncol 2020; cutoff: Mar 22, 2019); herein we report matured efficacy and safety data from FIGHT-202 (cutoff: Apr 7, 2020). Methods: Pts (≥18 y) with known FGF/FGFR alterations and progression after ≥1 prior therapy had FGFR2 rearrangements/fusions (cohort A), other FGF/FGFR alterations (B), or no FGF/FGFR alterations (C). Pts received PEMI 13.5 mg QD (21-d cycle; 2 wks on, 1 wk off) until progression or toxicity. Primary endpoint: independent, centrally confirmed ORR (cohort A); secondary endpoints: ORR (cohorts B, C; cohorts A and B combined); DOR, disease control rate (DCR), progression free survival (PFS), OS, and safety. A post-hoc analysis in cohort A evaluated mOS in responders (pts with complete response [CR] or partial response [PR]) vs non-responders (pts with progressive disease [PD] or stable disease (SD]). Results: At cutoff, 147 pts were enrolled (cohort A, n=108; B, n=20; C, n=17; FGF/FGFR status undetermined, n=2); median follow-up was 30.4 (range, 4.9–38.7) mo and median treatment duration was 5.9 (0.2–36.5) mo. In cohort A, 9.3% of pts remained on therapy at cutoff; in cohorts B and C, all pts had discontinued. Pts discontinued mainly for PD (67.6%, 75%, and 64.7% in cohorts A, B, and C respectively). Independent, centrally confirmed ORR was 37.0%; mOS was 17.5 mo (95% CI, 14.4-22.9) in cohort A (Table 1). mOS for responders (n=40) vs non-responders (n=68) was 30.1 (95% CI, 21.5-NE) mo vs 13.7 (9.6-16.1) mo. Overall, most common all-cause treatment-emergent adverse events (TEAEs) were hyperphosphatemia (58.5%; grade ≥3, 0%), alopecia (49.7%; 0%), diarrhea (46.9%; 3.4%), fatigue (43.5%; 5.4%), nausea (41.5%; 2%), and dysgeusia (40.8%; 0%); 10.2%, 13.6% and 42.2% of pts discontinued, had dose reduction, and treatment interruption due to TEAEs, respectively. Conclusions: These results reinforce the primary data, showing continued, durable responses and sustained tolerability in pts receiving PEMI for CCA harboring FGFR2 rearrangements/fusions. Notably, the matured OS is longer than historical data; OS for responders was more than twice as long vs for non-responders. Clinical trial information: NCT02924376. [Table: see text]