Borazanci, Erkut

ABSTRACT Background A randomized phase II screening trial of gemcitabine, nab‐paclitaxel, and cisplatin with a medically supervised ketogenic diet (MSKD) versus usual diet (non‐MSKD) was conducted in patients with treatment‐naive metastatic pancreatic ductal adenocarcinoma (PDAC). Methods Patients with untreated metastatic PDAC were randomized 1:1 to MSKD or non‐MSKD while receiving gemcitabine, nab‐paclitaxel, and cisplatin on days 1 and 8 of a 21‐day cycle. The MSKD was guided by a remote health care team and daily ketone (beta‐hydroxybutyrate) levels, with goal beta‐hydroxybutyrate of 0.5 to 3.0 mM. The primary endpoint was progression‐free survival (PFS) using a one‐sided alpha level of 0.20. Secondary endpoints included overall survival (OS), safety, and quality of life (QOL). Changes in microbiome were an exploratory endpoint. Findings Overall, there were 32 evaluable patients. In the MSKD arm, 15 of 16 patients achieved nutritional ketosis; the median proportion of days in ketosis was 39.4%. The median PFS was 8.5 months in MSKD patients and 6.2 months in non‐MSKD patients: hazard ratio, 0.53 (95% CI, 0.21–1.37); one‐sided p = .096. The median OS was 13.7 months with MSKD and 10.2 months in the non‐MSKD arm: hazard ratio, 0.58 (95% CI, 0.25–1.37); one‐sided p = .107). All MSKD‐related adverse events were grade 1‐2. There were no significant differences in grade ≥3 chemotherapy‐related adverse events between the arms. MSKD patients had no decline in QOL and had significant enrichment of beneficial taxa in the microbiome ( p < .05, log‐fold change ≥2). Conclusions The MSKD is feasible in patients with PDAC and, although not powered for definitive outcomes, shows trends in improved PFS and OS when combined with gemcitabine, nab‐paclitaxel, and cisplatin, without added toxicity or detriment to QOL. Larger studies are required to confirm these findings and establish the value of the MSKD in pancreatic cancer treatment.

Abstract Introduction: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with limited treatment options and poor survival. This study explores how a medically supervised ketogenic diet (MSKD) impacts the gut microbiome and treatment response in patients with newly diagnosed metastatic PDAC receiving gemcitabine, nab-paclitaxel, and cisplatin chemotherapy. Methods: As part of a randomized Phase II trial, 32 evaluable patients (median age 65.9 years; 53% male), 16 were randomized to either MSKD or standard diet (SD) combined with chemotherapy. Stool samples were collected from 4 patients in the MSKD group (13 samples) and 8 patients in the SD group (23 samples). Deep shotgun metagenomic sequencing was conducted using NovaSeq (Illumina). Taxonomical and functional microbiome characterization was performed using MetaPhlAn 4.0 and HUMAnN 3.6 (The Huttenhower Lab, Harvard). Comprehensive bioinformatics analyses, using QIIME2, were performed to analyze microbiome composition and function over time. Results: Patients in the MSKD group showed better treatment responses overall. Microbiome profiles between the two groups remained distinct throughout therapy. Though not statistically significant due to sample size, MSKD patients showed lower alpha diversity (Shannon diversity; p-value=0.1339), likely reflecting reduced intake of fermentable fiber. Differential abundance analysis using the ANCOM-BC method revealed a significant enrichment of beneficial taxa in the MSKD group compared to the SD group (p&lt;0.05, log-fold change [lfc]≥2), including Akkermansia muciniphila (linked to improved response to immune checkpoint inhibitors; p=0.017931, q=1), Intestinimonas butyriciproducens (a short-chain fatty acid [SCFA] and butyrate producer; p=3.09E-05, q=0.017), and Streptococcus thermophilus (a supporter of gut mucosal health; p=1.15E-05, q=0.006). During the course of the study, only MSKD patients showed sustained increases in Roseburia hominis (SFCA/butyrate producer; p=3.94E-05, q=0.021) and Lacticaseibacillus rhamnosus (with anti-inflammatory and immune-modulating properties; p=7.28E-19, q=3.98E-16), along with a marked reduction in potentially pro-inflammatory Actinomyces spp.(p≤4.47E-05, q≤0.024). Functional profiling showed increased abundance of cancer-relevant microbial pathways in MSKD patients, including phosphatidate metabolism (PWY-7039; involved in lipid signaling and immune regulation; p=4.36E-04, q=0.20) and allantoin degradation (PWY-5705; linked to redox balance; p=9.16E-06, q=0.004). Conversely, L-ascorbate biosynthesis V (PWY-6415) was reduced (p=3.80E-04, q=0.17), likely due to decreased D-galacturonate substrate availability from fiber restriction. Conclusion: These findings suggest that an MSKD may beneficially modulate the gut microbiome in ways that support and enhance therapeutic response in patients with PDAC. Further validation in a larger cohort is warranted to confirm these results and improve analytical resolution. Citation Format: Keehoon Lee, Derek Cridebring, Gayle S. Jameson, Denis J. Roe, Erkut Borazanci, Diana L. Hanna, Caroline G.P. Roberts, Meredith S. Pelster, Richard C. Frank, Angela T. Alistar, Alan M. Miller, J. Erin Wiedmeier-Nutor, Sandra D. Algaze, Alison R. Zoller, Sarah J. Hallberg, Betsy C. Wertheim, Joshua D. Rabinowitz, Stephen Gately, Jennifer Keppler, Sunil Sharma, Drew W. Rasco, Daniel D. Von Hoff. Ketogenic Diet Modulates Gut Microbiome Composition and Enhances Treatment Response in Patients with Advanced Pancreatic Cancer: A Phase II Study [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research—Emerging Science Driving Transformative Solutions; Boston, MA; 2025 Sep 28-Oct 1; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl_3):Abstract nr B094.

Abstract Lessons learned Intravenous paricalcitol did not improve the efficacy of pembrolizumab, likely related to the short half-life. Background Immunotherapy has limited benefit in the treatment of advanced pancreatic cancer with the tumor microenvironment playing a key role in immune resistance. In preclinical studies, vitamin D receptor (VDR) agonists have been shown to sensitize pancreatic tumors to PD-1 blockade. Methods This was a randomized, double-blinded, placebo-controlled, phase II trial to evaluate pembrolizumab with or without paricalcitol as maintenance therapy for patients with metastatic pancreatic ductal adenocarcinoma (PDAC). Participants were ≥18 years; histologically or cytologically confirmed metastatic PDAC showing no disease progression after frontline systemic therapy, and achieving maximal cytoreduction (eg, with no further antitumor effect), Eastern Cooperative Oncology Group (ECOG) status of 0 or 1; adequate organ function. Study treatment included: pembrolizumab 200 mg IV every 3 weeks and either paricalcitol 25 mcg IV 3 times per week or placebo. The primary objective was to evaluate 6-month progression free survival (PFS). Secondary objectives include evaluating the toxicity of the combination and overall survival (OS). Results There was no significant difference in 6-month PFS, median PFS, median OS, nor treatment-related AEs between the 2 arms. Conclusions and relevance Paricalcitol did not improve the efficacy of pembrolizumab likely related to its short half-life of only 5-7 hours. Microbiome analysis revealed significant difference between long-term (&gt;12 weeks) and short-term (&lt;12 weeks) survival groups across treatment arms. Modulation of the tumor microenvironment will likely require more sustained VDR activity. Trial Registration Clinicaltrials.gov, ID: NCT03331562.

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by stromal fibrosis, hypoxia, and nutritional deprivation. Nutritional metabolic interventions may fundamentally change the tumor microenvironment and improve outcomes. A ketogenic diet (KD) (lower carbohydrate, moderate protein, higher fat) can significantly reduce glucose and insulin and stimulate ketogenesis. Triplet chemotherapy with gemcitabine/cisplatin/nab-paclitaxel has been associated with a median OS 16.4 months, PFS 10.1 months in patients with metastatic PDAC in the first-line setting. Recently, KD plus triplet chemotherapy was shown to inhibit murine pancreatic KPC tumor growth and prolong animal survival over chemotherapy alone (Yang et al, Med, 2022). Tumor growth inhibition was associated with glucose depletion, altered TCA substrate use and NADH elevation. Methods: In this Phase II trial, patients with treatment-naive metastatic PDAC were randomized to triplet chemotherapy with a medically supervised ketogenic diet (MSKD) or continuing their usual diet (non-MSKD). The MSKD is supported by Virta Health, who offers tracking of daily ketone (beta-hydroxybutyrate, BHB) and glucose levels, a web-based application, education, and communication with a remote care team to ensure sustained nutritional ketosis (BHB 0.5–3.0mM). Patients with BMI &lt; 18, type 1 DM or history of DKA were excluded. Primary endpoint was PFS. Secondary endpoints: DCR (PR+CR+SD ≥ 9 weeks), change in CA 19-9 (CA125, CEA if not CA 19-9 expressers), average fasting insulin levels, HbA1c, body weight, gut microbiome, serum metabolites, QOL (QLQ- C30). Results: A total of 36 patients with untreated metastatic PDAC were enrolled. Among 32 evaluable patients (median age 65.9 years; 53% male), 16 were randomized to each arm. Both groups had similar baseline weight, HgbA1c, insulin and BHB levels (all p&gt;0.05). Nine patients had type 2 DM; 6 required insulin. In the MSKD group, 15/16 achieved nutritional ketosis at any point during the study, with mean BHB of 0.57 mM (95% CI 0.40–0.73) and median proportion of days in ketosis of 39.4% (range 0-95.8%) by daily ketone tracking. Lab data showed significantly higher mean ± SD maximum change in BHB in the MSKD (0.5 ± 0.9 mmol/L) versus non-MSKD (–0.2 ± 0.3 mol/L) group (p = 0.018). There were no significant differences between groups in maximum change in weight, HbA1C, or insulin (all p &gt; 0.05). The most common MSKD-related adverse events were Gr 1-2 fatigue (n=4), constipation (n=3), weight loss (n=3), and none stopped MSKD due to adverse events.Conclusion: A medically supervised ketogenic diet is feasible in patients with metastatic PDAC receiving triplet chemotherapy, with median proportion of days in ketosis of 39.4% and an acceptable safety profile. The MSKD is associated with comparable changes in insulin and HgbA1c levels compared to the non-MSKD diet, and sustained ketosis does not result in significantly greater weight loss. MSKD warrants further prospective exploration and analyses of the primary endpoint and correlative studies are ongoing. Citation Format: Gayle S Jameson, Erkut Borazanci, Diana L Hanna, Caroline GP Roberts, Meredith S Pelster, Richard C Frank, Angela T Alistar, Julia E Wiedmeier-Nutor, Sandra D Algaze, Brandon Fell, Sarah J Hallberg, Denise J Roe, Betsy C Wertheim, Derek Cridebring, Joshua D Rabinowitz, Stephen Gately, Daniel D Von Hoff, Drew W Rasco. Randomized phase II trial of two different nutritional approaches for patients receiving treatment for their advanced pancreatic cancer: initial results of safety and feasibility of the medically supervised ketogenic diet [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B012.

Abstract Background A previous phase IB/II study of nab‐paclitaxel + cisplatin + gemcitabine (NABPLAGEM) in 25 patients with previously untreated metastatic pancreatic ductal adenocarcinoma (PDAC) demonstrated favorable results. This phase II study was conducted to further evaluate the safety, efficacy, and impact on quality of life (QOL) of NABPLAGEM in a multi‐center setting. Methods Participants were ≥18 years; had measurable PDAC; Karnofsky performance status of ≥70%; life expectancy ≥12 weeks; <grade 2 pre‐existing peripheral neuropathy, and adequate hematologic, hepatic, and renal function. Study treatment included nab‐paclitaxel (125 mg/m 2 ), cisplatin (25 mg/m 2 ), and gemcitabine (1000 mg/m 2 ), on Days 1 and 8 of a 21‐day cycle. The primary endpoint was 12‐month overall survival (OS). Results A total of 42 patients were enrolled with a median age of 66.8 years, a majority were male (66.7%) and white (76.2%). Treatment‐related adverse events ≥grade 3 were: thrombocytopenia (64.3%), anemia (47.6%), and neutropenia (26.1%). OS at 12 months was 38.1%, with 12% of patients alive as of last contact (20–40+ months). In 37 evaluable participants responses included: partial response (40.5%), stable disease (43.2%), and progressive disease (16.2%), with overall response rate of 40.5% and DCR of 88.6%. Statistically significant improvement in QOL was reported during the first three cycles. Conclusion The primary objective of achieving a 12‐month survival comparable to the previous phase Ib/II NABPLAGEM PCRT 12‐001 was not achieved in this trial. NABPLAGEM has efficacy in advanced PDAC, demonstrating early disease control noted by improvement in patient symptoms, decrease in tumor volume and tumor markers within the first 9 weeks. The activity and tolerability make this a suitable regimen for further testing in the neoadjuvant setting.

Abstract Purpose: Tilsotolimod is an investigational synthetic Toll-like receptor 9 (TLR9) agonist that has demonstrated antitumor activity in preclinical models. The ILLUMINATE-101 phase I study explored the safety, dose, efficacy, and immune effects of intratumoral (it) tilsotolimod monotherapy in multiple solid tumors. Patients and Methods: Patients with a diagnosis of refractory cancer not amenable to curative therapies received tilsotolimod in doses escalating from 8 to 32 mg into a single lesion at weeks 1, 2, 3, 5, 8, and 11. Additional patients with advanced malignant melanoma were enrolled into an expansion cohort at the 8 mg dose. Objectives included characterizing the safety, establishing the dose, efficacy, and immunologic assessment. Blood samples and tumor biopsies of injected and noninjected lesions were obtained at baseline and 24 hours after treatment for immune analyses. Results: Thirty-eight and 16 patients were enrolled into the dose escalation and melanoma expansion cohorts, respectively. Deep visceral injections were conducted in 91% of patients. No dose-limiting toxicities (DLT) or grade 4 treatment-related adverse events were observed. Biopsies 24 hours after treatment demonstrated an increased IFN pathway signature and dendritic cell maturation. Immunologic profiling revealed upregulation of IFN-signaling genes and modulation of genes for checkpoint proteins. In the dose escalation cohort, 12 (34%) of 35 evaluable patients achieved a best overall response rate (ORR) of stable disease (SD), whereas 3 (19%) of 16 evaluable patients in the melanoma cohort achieved stable disease. Conclusions: Overall, tilsotolimod monotherapy was generally well tolerated and induced rapid, robust alterations in the tumor microenvironment. See related commentary by Punekar and Weber, p. 5007

TPS4181 Background: The mainstay of treatment (TX) for pts with advanced or mPDAC consists of CT, with FOLFIRINOX and gemcitabine (gem)/nab-paclitaxel currently representing the front-line standards of care. TX is generally continued until either dis progression (progr) or cumulative toxicity, with pts often reaching a plateau in response after 4-6 mos. For those who have achieved dis control (stable dis or better) on front-line CT, a maint TX strategy that can effectively delay dis progr while preserving quality of life with minimal cumulative toxicity is highly desirable. However, aside from PARP inhibition in the subset of PDAC pts with gBRCA mutated dis, there is no current standard of care in this maint setting. Ival is a pan-HDAC (histone deacetylation) inhibitor that increases histone acetylation (HA), suppresses PDAC cell proliferation, and promotes apoptosis in PDAC cell lines in a dose-dependent manner. It has demonstrated synergy with 5-FU in cholangiocarcinoma cell lines and shows promising antitumor activity when combined with cap in syngeneic PDAC mouse models. On these bases, we are conducting a ph1b/randomized ph2 trial of ival plus cap vs cap alone in the maint setting for pts with mPDAC who have not progressed on front-line FOLFIRINOX. Methods: Key eligibility criteria include pts with mPDAC; no evidence of dis progr following at least 16 wks of front-line FOLFIRINOX at full or modified doses; ECOG PS 0-1; and no known gBRCA1/2 mutation. The study includes an initial dose-esc ph1b evaluating 3 dose levels of ival, (60, 125, and 250mg/m2 iv weekly on days 1 and 8) in combination (comb) with cap (1000mg/m2 po BID on days 1-14) of a 21-day cycle, using a standard 3 + 3 dose-esc design. Of note, ival 250 mg/m2 represents the RP2D identified in prior clinical studies of this agent both as monotherapy in solid tumors and in comb with gem/erlotinib in advanced PDAC pts. In the ph2 portion, pts will be randomized 1:1 to receive either ival plus cap or cap alone, in 21-day cycles, until dis progr, with tumor assessments occurring at 6-wk intervals. Blood will be collected at pre-specified serial timepoints for pharmacodynamic assessments, including HA of PBMCs. Primary endpoint for ph2 is investigator-adjudicated PFS. The primary analysis will compare PFS distributions in the ival/cap and cap alone arms using a one-sided log rank test with an alpha = 0.10. The assumed true 6-mo PFS rates are 35% (cap), based on historic data, and 60% (ival/cap), which corresponds to an HR of 0.487. Assuming an accrual duration of 18 mos and a dropout/lost to follow-up rate of 10%, the estimated total number of pts in the randomized ph2 portion is 52 (26 per arm). Enrollment is expected to being in spring 2022 across 25 U.S. sites.

26 Background: NKTR-262 is a novel intratumoral prodrug designed to promote tumor antigen release, an immune stimulatory environment, and antigen presentation. NKTR-214 increases CD8+ T cells and NK cells in the tumor microenvironment. The combination of NKTR-262 with NKTR-214 accesses innate and adaptive immunity to provide an abscopal response and systemic tumor immunity. The Phase 1b/2 REVEAL trial is enrolling. Methods: In a 3+3 Phase 1 design, pts who are relapsed/refractory to ≥1 CPI receive escalating doses of intratumoral (IT) NKTR-262 followed by combined q3w treatment of IT NKTR-262 and fixed-dose intravenous (IV) NKTR-214 (0.006 mg/kg). Phase 1 will evaluate PK, safety, efficacy, and determine recommended Phase 2 dose. Scans are conducted every 9 wks (± 1 wk). Peripheral blood (PB) and tumor tissue are collected to measure biomarkers of immune activation. In Phase 2 expansion, NKTR-262 + NKTR-214 ± IV nivolumab (360 mg) will be assessed in specific tumor cohorts of IO-naïve and experienced pts. Results: As of 06 Nov 2018, 11 pts had received at least one cycle of NKTR-262 + NKTR-214 therapy. 7/11 pts were efficacy evaluable with at least one on-treatment scan (4 MEL, 2 SARC, 1 CRC). 2/4 R/R melanoma pts had uPRs with 100% (scan 2) and 40% (scan 1) reductions in target lesions per RECIST 1.1, respectively. Both patients remain on treatment. Two SARC pts had stable disease at scan 1. No pts experienced G3 or higher TRAEs or immune-related adverse events (AEs). Most common G1-2 AEs were transient flu-like symptoms. Gene expression analysis of tumor and PB show dose-dependent induction (4 to 16-fold) of TLR target genes. Consistent with the mechanism of action for NKTR-214, PB flow cytometry shows an average 13-fold increase from baseline in Ki67+ CD8+T cells in 6 pts. Conclusions: NKTR-262 + NKTR-214 engage the immune activation cascade from local tumor antigen production to anti-tumor T cell response. Initial dose levels of NKTR-262 with fixed-dose NKTR-214 were well-tolerated with early evidence of clinical activity. These data support continued evaluation of the combination +/- nivolumab. Clinical trial information: NCT03435640.