Preclinical Evaluation of a Novel Hyperbolic NAMPT Inhibitor in Combination with Pan-RAS Targeted Therapies in Pancreatic Ductal Adenocarcinoma

Document Type

Conference Proceeding

Publication Date

4-3-2026

Publication Title

Cancer Res

Keywords

Oncology

Abstract

Background: Pancreatic ductal adenocarcinoma (PDAC) remains highly lethal, driven by near-universal KRAS mutations and profound metabolic dependence on nicotinamide adenine dinucleotide (NAD). NAMPT, the rate-limiting enzyme of the NAD salvage pathway, is frequently upregulated in KRAS-driven tumors, suggesting metabolic co-dependence. We evaluated whether simultaneous blockade of NAMPT and KRAS signaling enhances antitumor efficacy in PDAC. Methods: KRAS-NAMPT expression correlations were analyzed in TCGA PDAC samples (n=179). Multiple KRAS-mutant PDAC cellular models, including KRASG12C inhibitor, KRASG12D inhibitor, and pan-RAS inhibitor (RMC6236)-resistant lines were treated with the hyperbolic NAMPT inhibitor RPT-E-037, RMC6236, or both. Antitumor activity was assessed in 2D viability assays, 3D spheroid cultures, and patient-derived 2D/3D co-culture systems. Drug interactions were calculated using combination index (CI) analysis. Results: TCGA analysis revealed a fairly strong positive correlation between KRAS and NAMPT expression (Spearman ρ=0.59). RMC6236-resistant PDAC cells displayed increased NAMPT expression and heightened sensitivity to RPT-E-037 compared to parental cells. Similar NAMPT upregulation and enhanced NAMPT inhibitor sensitivity were observed in KRASG12C and KRASG12D inhibitor-resistant models. Across KRAS-mutant PDAC lines, RPT-E-037 combined with RMC6236 produced robust synergy (CI<1) in both 2D and 3D cultures. In patient-derived PDAC co-culture systems, the combination significantly reduced tumor mass, dismantled compact spheroid architecture, and disrupted tumor-stroma interactions more effectively than either agent alone. KRASG12D-mutant metastatic patient rapid autopsy tissue-derived and KPC mice tumor-derived subcutaneous and orthotopic xenograft studies with the combination are ongoing. Conclusion: Dual inhibition of NAMPT-mediated NAD biosynthesis and KRAS signaling yields synergistic antitumor activity in PDAC, including models resistant to KRAS-targeted therapies. These findings support NAMPT-KRAS co-dependency as a therapeutically actionable vulnerability and justify further translational and in vivo studies to guide clinical development and biomarker-based patient selection."Generative AI was used for improving the language of the abstract".

Volume

86

Issue

7

First Page

1

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