KRAS Mutant Non-small Cell Lung Research Articles

Abstract CT163: FIT-001: A phase 1 clinical trial of the farnesyl transferase inhibitor KO-2806 alone or as part of combination therapy for advanced solid tumors

Abstract Background: Farnesyl transferase inhibitors (FTIs) block post-translational modification of RAS and other farnesylated proteins. HRAS-driven tumors are highly sensitive to FTI treatment. Recent clinical trials (NCT03719690, NCT02383927) of the FTI, tipifarnib, in patients with HRAS-mutant (HRAS-m) head and neck squamous cell carcinoma harboring high variant allele frequency mutations (VAF ≥20%), showed objective response rates of up to 50% and favorable long-term outcomes. KO-2806 is a next-generation FTI that has increased potency and improved pharmacokinetic properties. In preclinical studies, KO-2806 has been shown to: (1) enhance tumor growth inhibition of tyrosine kinase inhibitors, including cabozantinib, in multiple clear cell renal cell carcinoma (ccRCC) cell line- and patient-derived xenograft models; and (2) enhance activity of KRAS inhibitors, including adagrasib, in KRAS mutant non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and pancreatic ductal adenocarcinoma (PDAC) mouse models. These preclinical data support clinical investigation of KO-2806 alone and in combination therapy. Study Design: FIT-001 is a first-in-human, multicenter, open-label clinical trial that will evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics (Pd), and preliminary antitumor activity of KO-2806 as monotherapy or in combination therapy in advanced solid tumors (KO-2806-001; NCT06026410). Up to 270 patients will be enrolled in phase 1a and phase 1b combined across 50 sites. Phase 1a will have separate monotherapy and combination dose-escalation arms. As monotherapy, the study will enroll patients with N/K/HRAS alterations in specific solid tumor types, such as NSCLC, CRC, and PDAC, who are refractory to standard-of-care therapies. KO-2806 and cabozantinib will be combined in patients with advanced or metastatic ccRCC who progressed on ≥1 prior line of immunotherapy-based systemic therapy; KO-2806 and adagrasib will be combined in patients with KRAS-G12C mutant locally advanced or metastatic NSCLC who received ≥1 prior systemic therapy. On the basis of emerging data from phase 1a, two Pd cohorts (n≤12) with mandatory pre- and on-treatment tumor biopsies may be enrolled. In each Phase 1b dose expansion, patients will receive the recommended phase 2 dose [RP2D] of KO-2806 with cabozantinib (in ccRCC) or adagrasib (in NSCLC), or will be randomized by dose if 2 potential KO-2806 RP2Ds are identified for a combination. Other combination arms may also be considered. The study began accrual in October 2023. Citation Format: Glenn J. Hanna, Douglas R. Adkins, Jacob S. Thomas, Justine Y. Bruce, Manish R. Patel, Guru Sonpavde, Jason Henry, Nawal Bendris, Zijing Zhang, Amitava Mitra, Amaya Gascó, Andrew Saunders, Stephen Dale. FIT-001: A phase 1 clinical trial of the farnesyl transferase inhibitor KO-2806 alone or as part of combination therapy for advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT163.

Abstract B081: Aurora kinase A inhibition overcomes adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer

Abstract Cancer cells gain drug-tolerant states and evade therapy. In response to KRAS G12C inhibitor (G12Ci), KRAS mutant non-small cell lung cancer (NSCLC) cells maintain a drug-tolerant state by aurora kinase A (AURKA). AURKA can phosphorylate c-Raf to maintain new KRAS signaling, however, how AURKA becomes activated to cause KRAS G12Ci resistance is unclear. We show here that KRAS G12C + AURKA inhibition cause synthetic lethality in KRAS G12C NSCLC cells. LY3499446 (KRAS G12Ci) and LSN3321213 (aurora kinase A inhibitor) induced apoptosis that is independent of inhibited MAPK reactivation. Using high-content imaging that tracks single-cell fate during treatment, we observed that single-agent KRAS G12Ci induces G1 arrest in a sub-population of cells. Upon co-treatment with G12C + AURKAi, cells that are halted in G1 phase undergo early apoptosis, while those that initially evade G1 arrest and proceed through G2/M undergo apoptosis in subsequent G1. These data suggest the hypothesis that AURKA inhibition may increase the probability of G1 checkpoint-induced apoptosis by facilitating chromosomal misalignment and genomic instability in G2. In summary, we provide pre-clinical rationale for clinical testing of KRAS G12C + AURKA inhibitors. We also suggest a novel mechanism explaining the dependency of KRAS G12C resistant subpopulations on AURKA, leading to the opportunity to investigate the role of genomic instability in conferring KRAS G12Ci adaptive resistance. Citation Format: Chendi Li, Jeremy Chang, Christopher J Graser, Usman M Syed, Anahita Nimbalkar, Yi Shen, Steve Altschuler, Lani Wu, Franziska Michor, Xueqian Gong, Aaron N Hata. Aurora kinase A inhibition overcomes adaptive resistance to KRAS G12C inhibitor by G1-checkpoint induced apoptosis in KRAS non-small cell lung cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B081.

Abstract B080: Non-genetic determinants driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer

Abstract The FDA approval of the KRAS G12C inhibitor (G12Ci) sotorasib and the advancement of similar drugs into the clinic marks a major milestone in treating KRAS G12C non-small cell lung cancer (NSCLC). However, not all patients respond (sotorasib – ORR = 37.1%, adagrasib - 43%, JDQ443 – 35%), motivating preclinical and clinical investigation into mechanisms of intrinsic and acquired resistance. For instance, clinical studies have reported on-target KRAS mutations and preclinical studies have demonstrated mitogen-activated protein kinase (MAPK) feedback reactivation including EGFR, SHP2, and WT RAS signaling. In response to targeted therapies, sub-populations of cells can enter quiescence or specific epigenetic-driven states that confer drug tolerance. However, epigenetic states defining drug-tolerant persister populations and contributing to adaptive resistance to KRAS G12Ci have not been reported. Using a high-complexity DNA-barcoding system and mathematical modeling, we observed that pre-existing resistant clones to KRAS G12Ci gain clonal fitness during treatment independent of growth rate. Using single-cell profiling and RNA-lineage tracing barcoded systems, we identified distinct subpopulations of cells defined by specific chromatin and transcriptional states, including activation of interferon-gamma genes (ISG) and increased chromatin accessibility for pioneer transcription factors, which may contribute to MAPK reactivation-driven resistance. These results suggest a potential role of pioneer transcription factor-activated interferon-gamma response in driving MAPK feedback reactivation in KRAS G12Ci- resistant tumor subpopulations. Citation Format: Chendi Li, Christopher J Graser, Qian Qin, Usman M Syed, Barbara Karakyriakou, Sarah E Clark, Anne Y Saiki, Paul E Hughes, Christopher Ott, Luca Pinello, Franziska Michor, Aaron N Hata. Non-genetic determinants driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B080.

Abstract LB_C17: Spatial tumor immune microenvironment analysis of KRAS-mutated Non-Small Cell Lung Cancer and immunotherapy outcome

Abstract Targeting KRAS in lung cancer is promising and the immune modulatory effects of KRAS inhibition is interesting. Understanding the local tumor immune architectures are important to overcome the treatment resistance of immunotherapy and targeted therapy. We conducted spatial immune tumor microenvironment (iTME) profiling using FFPE samples of 25 KRAS mutated non-small cell lung cancer patients treated with immune checkpoint inhibitors (ICIs), which included 12 responders and 13 non-responders. We used an eleven-markers panel (CD3, CD4, CD8, Foxp3, CD68, Arginase-1, CD33, HLA-DR, Pan-Keratin (PanCK), PD-1 and PD-L1). We studied the tumor and immune cell compositions and spatial features at single cell level with cellular neighborhood and fractal analysis. We found spatial features and the different subgroups of CD68 positive cells and Foxp3+ cells associated with responses and resistance to ICIs. We found that CD68+ cells, CD33+ cells and Foxp3+ cells are associated with resistance to ICIs of KRAS mutated lung cancer. Interestingly, we found that cells had non-nuclear expression of Foxp3 were associated with ICIs resistance. We identified a population of CD68 weakly positive cells in the tumor tissues were associated with responses to ICIs. We identified two different groups of non-responders: one with high diversity of cells and one with low diversity, while all the responders had high diversity. We identified nine cellular neighborhoods (C0-C8) with C0 in majority of non-responders, which was enriched with PanCK+, CD33+, and Foxp3+ T regulartory cells. Conversely, most responders were enriched with C3 and C6-C7, which contained CD8+ T cells and CD68 weakly positive cells. Our study had revealed the spatial immune features of KRAS mutated lung cancer and their association with immunotherapy outcome which could be helpful for KRAS targeting and immunotherapy. Citation Format: Dan Zhao, Haiqing Li, Isa Mambetsariev, Tamara Mirzapoiazova, Chen Chen, Jeremy Fricke, Deric Wheeler, Leonidas Arvanitis, Raju Pillai, Michelle Afkhami, Bihong T. Chen, Martin Sattler, Loretta Erhunmwunsee, Erminia Massarelli, Prakash Kulkarni, Arya Amini, Brian Armstrong, Ravi Salgi. Spatial tumor immune microenvironment analysis of KRAS-mutated Non-Small Cell Lung Cancer and immunotherapy outcome [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_C17.

420P Combinatory genomic and transcriptomic sequencing of Chinese KRAS mutant non-small cell lung cancer revealed molecular and inflammatory heterogeneity in tumor microenvironment

420P Combinatory genomic and transcriptomic sequencing of Chinese KRAS mutant non-small cell lung cancer revealed molecular and inflammatory heterogeneity in tumor microenvironment

EP11.03-05 Molecular Characterization and Prognosis of Patients with KRAS Mutant Non-small Cell Lung Cancer

EP11.03-05 Molecular Characterization and Prognosis of Patients with KRAS Mutant Non-small Cell Lung Cancer

EP09.04-01 Prognostic Factors for Patients With KRAS Mutated Non-Small Cell Lung Cancer and Brain Metastases

EP09.04-01 Prognostic Factors for Patients With KRAS Mutated Non-Small Cell Lung Cancer and Brain Metastases

Early Changes in Circulating Cell-Free KRAS G12C Predict Response to Adagrasib in KRAS Mutant Non-Small Cell Lung Cancer Patients.

Non-invasive monitoring of circulating tumor DNA (ctDNA) has the potential to be a readily available measure for early prediction of clinical response. Here, we report on early ctDNA changes of KRAS G12C in a Phase 2 trial of adagrasib in patients with advanced, KRAS G12C-mutant lung cancer. We performed serial droplet digital PCR (ddPCR) and plasma NGS on 60 KRAS G12C-mutant patients with lung cancer that participated in cohort A of the KRYSTAL-1 clinical trial. We analyzed the change in ctDNA at 2 specific intervals: Between cycles 1 and 2 and at cycle 4. Changes in ctDNA were compared with clinical and radiographic response. We found that, in general, a maximal response in KRAS G12C ctDNA levels could be observed during the initial approximately 3-week treatment period, well before the first scan at approximately 6 weeks. 35 patients (89.7%) exhibited a decrease in KRAS G12C cfDNA >90% and 33 patients (84.6%) achieved complete clearance by cycle 2. Patients with complete ctDNA clearance at cycle 2 showed an improved objective response rate (ORR) compared with patients with incomplete ctDNA clearance (60.6% vs. 33.3%). Furthermore, complete ctDNA clearance at cycle 4 was associated with an improved overall survival (14.7 vs. 5.4 months) and progression-free survival (HR, 0.3). These results support using early plasma response of KRAS G12C assessed at approximately 3 weeks to anticipate the likelihood of a favorable objective clinical response.

Abstract 4155: The RAF/MEK clamp avutometinib (VS-6766) induces an immunogenic tumor microenvironment and potentiates the efficacy of anti-PD-1

Abstract The RAS/RAF/MEK/ERK (MAPK) pathway is one of the most commonly mutated oncogenic pathways in human cancers. Although RAS, RAF and MEK have been validated as anticancer targets with approval of KRAS G12C, BRAF and MEK inhibitors, combination strategies with chemotherapy, targeted therapies and/or immune checkpoint inhibitors may be optimal for deep and durable response. Avutometinib (avuto, VS-6766) is a unique RAF/MEK clamp that potently inhibits MEK kinase activity and induces a dominant negative RAF/MEK complex preventing phosphorylation of MEK by ARAF, BRAF and CRAF. Preclinically, avuto has shown strong anti-proliferative potency across tumor cell lines carrying various MAPK pathway alterations. Clinically, avuto monotherapy has shown responses in gynecological cancers and KRAS mutant non-small cell lung cancer. Here, we tested the immune modulatory effects of avuto on tumor cells and tumor-infiltrating immune cells and assessed anti-tumor efficacy in mice treated with avuto in combination with an anti-PD1 antibody. In a panel of KRAS and BRAF mutant human tumor cell lines, avuto treatment increased the expression of MHC-I complex genes, including B2M, HLA-A and TAP1. In the CT26 KRAS G12D syngeneic colorectal cancer model, upregulation of B2M and TAP1 by avuto was confirmed in vivo, suggesting that avuto may increase antigen presentation. Furthermore, avuto upregulated the expression of markers of T cells (CD8, PDCD1), NK cell activation (NCR1) and interferon response (IFNG, IRF7, IL12) in the CT26 model. Interestingly, all these pro-immune changes observed with avuto were stronger than those observed with an equivalent dose level of the MEK-only inhibitor trametinib. Avuto also increased expression of B2M, CD8A, PDCD1, NCR1 and IRF7 in a KPARG12C orthotopic lung cancer model. Flow cytometry analysis showed that avuto also significantly increased MHC-II expression by tumor cells and the numbers of CD8 T cells and M1 macrophages, and significantly decreased monocytic and granulocytic MDSCs. These immune changes indicate that avuto induces an immunogenic tumor microenvironment that may potentiate the efficacy of immuno-oncology agents such as anti-PD-1. Accordingly, in the CT26 model, whereas avuto and anti-PD-1 each delayed tumor growth, combination of avuto with anti-PD-1 increased antitumor efficacy and prolonged survival. Furthermore, all complete responders in the avuto + anti-PD-1 group were able to reject a re-challenge with CT26 tumor cells and showed increased CD8 and CD4 effector memory T cells relative to untreated naïve control mice, indicating that avuto + anti-PD-1 treatment induces durable immune memory. These results support clinical evaluation of avutometinib in combination with an anti-PD-1 antibody for treatment of patients with solid tumors harboring MAPK pathway alterations such as KRAS or BRAF mutations. Citation Format: Silvia Coma, Miriam Molina Arcas, Julian Downward, Jonathan A. Pachter. The RAF/MEK clamp avutometinib (VS-6766) induces an immunogenic tumor microenvironment and potentiates the efficacy of anti-PD-1. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4155.

Abstract 3867: Chromatin modification driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer

Abstract The FDA approval of the KRAS G12C inhibitor (G12Ci) sotorasib and the advancement of similar drugs into clinical trials marks a major milestone in treating KRAS G12C non-small cell lung cancer (NSCLC). However, not all patients respond (sotorasib - ORR = 37.1%, adagrasib - 43%, JDQ443 - 35%), motivating preclinical and clinical investigation into mechanisms of intrinsic and acquired resistance. For instance, clinical studies have reported on-target KRAS mutations and preclinical studies have demonstrated mitogen-activated protein kinase (MAPK) feedback reactivation including EGFP, SHP2, and WT RAS signaling. In response to targeted therapies, sub-populations of cells can enter quiescence or specific epigenetic-driven states that confer drug tolerance. However, epigenetic states defining drug-tolerant persister populations and contributing to adaptive resistance to KRAS G12Ci have not been reported. Using a lineage tracing barcoded system, we identify distinct and reversible subpopulations defined by specific chromatin and transcriptional states in KRAS NSCLC cell lines that contribute to KRAS G12Ci resistance in vitro, even prior to drug treatment. We observed that specific states, including activation of histone demethylation and SWI/SNF complex, may contribute to MAPK reactivation-driven resistance. These results suggest potential epigenetic vulnerabilities that can be exploited to improve the response to KRAS G12Ci. Moreover, we observed distinct persister subpopulations with resistance to KRAS G12Ci combination co-targeting orthogonal pathways (SHP2, CDK4/6, PI3K, and MCL-1), raising the possibility that distinct epigenetic-transcriptional states contribute to differential drug response and clonal evolution of persisters. Collectively, these results suggest that more complete tumor regression may be achieved by orthogonal strategies that target different resistant populations within the same tumor. Citation Format: Chendi Li, Qian Qin, Mohammed Usman Syed, Anahita Nimbalkar, Barbara Karakyriakou, Sarah E. Clark, Anne Y. Saiki, Paul E. Hughes, Chris Ott, Luca Pinello, Aaron N. Hata. Chromatin modification driving sub-clonal resistance to KRAS G12C combination therapies in KRAS mutant non-small cell lung cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3867.

Highlights from Recent Cancer Literature.

Highlights from Recent Cancer Literature.

A single center analysis of first-line treatment in advanced KRAS mutant non-small cell lung cancer: real-world practice

PurposeFor the first-line treatment of KRAS mutant non-small cell lung cancer (NSCLC) patients, immunotherapy or platinum-based chemotherapy are the main treatment method. Here, we investigated the clinical efficacy and prognosis those two regimens as first-line treatment in real-world practice.MethodsKRAS mutant NSCLC patients received chemotherapy or immunotherapy as first-line treatment from September 2014 to March 2022 were enrolled. Clinical characteristics, treatment scheme, clinical curative effect and follow-up data of enrolled patients were collected for analysis.ResultsFifty patients received immunotherapy and 115 patients received chemotherapy were enrolled. Patients who received immunotherapy (HR = 0.350, 95%CI 0.156–0.781, P = 0.010), or pemetrexed-based regimen (HR = 0.486, 95%CI 0.255–0.928, P = 0.029), or antiangiogenic therapy (HR = 0.355, 95%CI 0.159–0.790, P = 0.011) were at a low risk of disease progression. And patients received antiangiogenic therapy had lower risk of death than those not (HR = 0.333, 95%CI 0.120–0.926, P = 0.035). Subgroup analysis revealed the immunotherapy compared to chemotherapy alone had lower risk of disease progression (HR = 0.377, 95%CI 0.166–0.856, P = 0.020) in PD-L1 expression ≥1% subgroup. And in non-G12C KRAS subgroup, but not in G12C KRAS subgroup, patients who received antiangiogenic therapy had lower risk of disease progression (HR = 0.254, 95%CI 0.098–0.656, P = 0.005) and death than those not (HR = 0.197, 95%CI 0.056–0.692, P = 0.011). In terms of different chemotherapy regimen, platinum-paclitaxel combined with antiangiogenic therapy achieved the highest ORR and DCR (P < 0.05), while the platinum-pemetrexed combined with antiangiogenic therapy had the longest PFS and OS (P < 0.001).ConclusionFor the first-line treatment of KRAS mutant NSCLC patients, immunotherapy, antiangiogenic therapy, and pemetrexed-based regimen could obtain more benefits. Subgroup analysis revealed the benefits of immunotherapy compared to chemotherapy were applicable in PD-L1 expression≥1% subgroup, and antiangiogenic therapy could benefit non-G12C KRAS subgroup, but not G12C KRAS subgroup. In terms of different chemotherapy regimen, platinum-pemetrexed combined with antiangiogenic therapy may be the preferred chemotherapy regimen.

EP08.02-097 Prevalence, Clinical Characteristics and Survival of Patients With Brain Metastases and KRAS Mutation Lung Cancer in Argentina

Between 20-35% of lung adenocarcinomas harbor KRAS gene mutations (KRASm). With the development of KRAS G12C covalent inhibitors as novel targeted therapies in this population, there is renewed interest in understanding the clinical features and outcomes of patients with KRAS mutant non-small cell lung cancer (NSCLC) worldwide.

Comprehensive analysis of T cell receptor repertoire in patients with KRAS mutant non-small cell lung cancer.

BackgroundKirsten rat sarcoma viral oncogene homolog (KRAS) is one of the most frequently mutated oncogenes in non-small cell lung cancer (NSCLC). The administration of immunotherapy has demonstrated significant efficacy in prolonging the overall survival of patients with KRAS mutation in recent years. However, the efficacy of immunotherapy in KRAS mutant NSCLC is variable. Analysis of T cell receptor (TCR) repertoire may contribute to a better understanding of the mechanisms behind such differential outcomes.MethodsA total of 47 patients with KRAS mutant NSCLC were enrolled in this study. Deep sequencing of the TCR β chain complementarity-determining regions in tumor tissue and paired peripheral blood specimens was conducted. Comprehensive analysis of TCR repertoire metrics was performed with different KRAS mutation subtypes and concomitant mutations. Moreover, the associations between TCR repertoire metrics and tumor mutation burden (TMB), as well as programmed death-ligand 1 were explored, respectively.ResultsTCR repertoire metrics, including Shannon index, Clonality, and Morisita index (MOI), showed no significant differences among different KRAS mutation subtypes. The similar results were observed between patients with tumor protein p53 (TP53) mutation and those with wild-type TP53. In contrast, although no significant differences were found in Shannon index and Clonality, patients with KRAS/serine/threonine kinase 11 (STK11) comutation showed a significantly higher MOI compared to their STK11 wild-type counterparts (P=0.012). In addition, TCR repertoire metrics were neither associated with TMB nor programmed death-ligand 1 expression in KRAS mutant NSCLC.ConclusionsThis retrospective study comprehensively described the TCR repertoire in KRAS mutant NSCLC. A higher MOI represented more overlap of the TCR repertoire between tumor tissue and paired peripheral blood, indicating distinctive immunological features in NSCLC with KRAS/STK11 comutation.

EP08.02-135 Anti-EGF Antibodies Significantly Improve the Activity of MET and KRAS Inhibitors in Preclinical Models of Non-small Cell Lung Cancer (NSCLC)

The EGF/EGFR pathway is involved in the emergence of resistance to MET and KRAS inhibitors. Vaccination represents an alternative to the administration of anti-EGFR monoclonal antibodies such as cetuximab or panitumumab, and we have shown that antibodies against EGF (anti-EGF VacAbs) potentiate the effects of tyrosine kinase inhibitors in vitro (TKIs). Also, a progression-free survival of 18 months was obtained in a recent Phase Ib clinical trial combining afatinib with anti-EGF VacAbs. In this study, we tested if anti-EGF VacAbs could improve the antitumor activity of capmatinib, tepotinib and sotorasib in MET amplified, MET Δ14 and KRAS mutant non-small cell lung cancer (NSCLC) cell lines.

EP08.01-086 Pooled Mutant KRAS-Targeted Peptide Vaccine with Nivolumab and Ipilimumab in Advanced KRAS Mutated Non-Small Cell Lung Cancer

Treatment for advanced non-small cell lung cancer (NSCLC) has been revolutionized by the development of both immunotherapeutic and genomic based therapies. There is increasing appreciation for the interplay between genomic alterations and response to immune checkpoint blockade (ICB), as exhibited by alterations in driver mutations (e.g. EGFR/ALK) and non-driver co-mutations (e.g. STK11/KEAP1). Special attention has been paid to the most common oncogenic driver, KRAS, which is mutated in approximately 30% of NSCLC.

Molecular Biology and Therapeutic Perspectives for K-Ras Mutant Non-Small Cell Lung Cancers.

Simple SummaryMutations in the Kirsten rat sarcoma viral oncogene homolog (KRAS) gene are the most common alterations in non-small cell lung cancer (NSCLC); they are generally linked to smoking history and are typical of the lung adenocarcinoma (AC) subtype. The clinical relevance of KRAS mutations in NSCLC was generally low or null until a few years ago. What is now emerging is that KRAS-mutant lung AC patients are generally associated with poorer survival. However, the approval of Sotorasib, a KRAS inhibitor, improved the survival of a previously untargetable KRAS-mutant lung AC group. Furthermore, new approaches targeting KRAS are under development. Starting from the description of the biology of KRAS-mutant NSCLC, the present review focuses on the clinical aspects of KRAS mutations in NSCLC. Finally, the interaction between KRAS mutations and immune checkpoint inhibitors will also be discussed.In non-small cell lung cancer (NSCLC) the most common alterations are identified in the Kirsten rat sarcoma viral oncogene homolog (KRAS) gene, accounting for approximately 30% of cases in Caucasian patients. The majority of mutations are located in exon 2, with the c.34G > T (p.G12C) change being the most prevalent. The clinical relevance of KRAS mutations in NSCLC was not recognized until a few years ago. What is now emerging is a dual key role played by KRAS mutations in the management of NSCLC patients. First, recent data report that KRAS-mutant lung AC patients generally have poorer overall survival (OS). Second, a KRAS inhibitor specifically targeting the c.34G > T (p.G12C) variant, Sotorasib, has been approved by the U.S. Food and Drug Administration (FDA) and by the European Medicines Agency. Another KRAS inhibitor targeting c.34G > T (p.G12C), Adagrasib, is currently being reviewed by the FDA for accelerated approval. From the description of the biology of KRAS-mutant NSCLC, the present review will focus on the clinical aspects of KRAS mutations in NSCLC, in particular on the emerging efficacy data of Sotorasib and other KRAS inhibitors, including mechanisms of resistance. Finally, the interaction between KRAS mutations and immune checkpoint inhibitors will be discussed.

Efficacy of Combined Use of Everolimus and Second-Generation Pan-EGRF Inhibitors in KRAS Mutant Non-Small Cell Lung Cancer Cell Lines.

Background: EGFR mutations are present in approximately 15–50% of non-small cell lung cancer (NSCLC), which are predictive of anti-EGFR therapies. At variance, NSCLC patients harboring KRAS mutations are resistant to those anti-EGFR approaches. Afatinib and allitinib are second-generation pan-EGFR drugs, yet no predictive biomarkers are known in the NSCLC context. In the present study, we evaluated the efficacy of pan-EGFR inhibitors in a panel of 15 lung cancer cell lines associated with the KRAS mutations phenotype. Methods: KRAS wild-type sensitive NCI-H292 cell line was further transfected with KRAS mutations (p.G12D and p.G12S). The pan-EGFR inhibitors’ activity and biologic effect of KRAS mutations were evaluated by cytotoxicity, MAPK phospho-protein array, colony formation, migration, invasion, and adhesion. In addition, in vivo chicken chorioallantoic membrane assay was performed in KRAS mutant cell lines. The gene expression profile was evaluated by NanoString. Lastly, everolimus and pan-EGFR combinations were performed to determine the combination index. Results: The GI50 score classified two cell lines treated with afatinib and seven treated with allitinib as high-sensitive phenotypes. All KRAS mutant cell lines demonstrated a resistant profile for both therapies (GI50 < 30%). The protein array of KRAS edited cells indicated a significant increase in AKT, CREB, HSP27, JNK, and, importantly, mTOR protein levels compared with KRAS wild-type cells. The colony formation, migration, invasion, adhesion, tumor perimeter, and mesenchymal phenotype were increased in the H292 KRAS mutated cells. Gene expression analysis showed 18 dysregulated genes associated with the focal adhesion-PI3K-Akt-mTOR-signaling correlated in KRAS mutant cell lines. Moreover, mTOR overexpression in KRAS mutant H292 cells was inhibited after everolimus exposure, and sensitivity to afatinib and allitinib was restored. Conclusions: Our results indicate that allitinib was more effective than afatinib in NSCLC cell lines. KRAS mutations increased aggressive behavior through upregulation of the focal adhesion-PI3K-Akt-mTOR-signaling in NSCLC cells. Significantly, everolimus restored sensibility and improved cytotoxicity of EGFR inhibitors in the KRAS mutant NSCLC cell lines.

Abstract 1179: Rational combinations with the dual RAF/MEK inhibitor VS-6766 for treatment of cutaneous melanoma harboring BRAF, NRAS, NF1 or CRAF mutations

Abstract VS-6766 is a unique dual RAF/MEK inhibitor which blocks MEK activity without the compensatory MEK activation that limits the efficacy of MEKi. VS-6766 produced clinical responses as a single agent in gynecological cancers and KRAS mutant non-small cell lung cancer (NSCLC) (Guo Lancet Oncology 2020). Clinical responses were also observed with VS-6766 in combination with the focal adhesion kinase (FAK) inhibitor defactinib in patients with low-grade serous ovarian cancer and KRAS mutant NSCLC. In patients with advanced cutaneous melanoma, mutations in the RAS/RAF/MEK/ERK (MAPK) pathway occur mainly in BRAF (41%), NRAS (27%), NF1 (25%) and CRAF (2.6%) (AACR Genie v10). Although several selective BRAFV600 inhibitors (BRAFi) are FDA-approved alone or in combination with MEK-only inhibitors (MEKi) for melanomas with BRAFV600E/K, there is still a need for agents to improve response rate, duration of response, and tolerability. There are no targeted therapy options for melanoma patients carrying NRAS or NF1 mutations following progression on immune checkpoint inhibitors. Using low passage cell lines derived from patients with metastatic melanoma and extensively profiled for genomic alterations together with commercially available immortalized human melanoma cell lines, all of which carried mutations in the MAPK pathway, we tested the activity of VS-6766 alone or in combination with other agents. In vitro proliferation assays showed that VS-6766 is as potent as BRAFi in BRAFV600E melanoma cell lines and is more potent than pan-RAF inhibitors in melanoma cell lines bearing NRAS, NF1 or CRAF mutations. We next tested rational combinations of VS-6766 with other agents in specific genetic backgrounds. In BRAFV600E melanoma cell lines, combination of VS-6766 with BRAFi (encorafenib, vemurafenib, dabrafenib) showed greater synergy than combination of MEKi (binimetinib, cobimetinib, trametinib) with BRAFi. Since ~65% of BRAF or NRAS mutant melanomas co-express mutations in the PI3K/AKT/mTOR pathway, we tested the combination of VS-6766 with the mTOR inhibitor everolimus. VS-6766 was synergistic with everolimus in reducing the viability of melanoma cells harboring BRAF or NRAS mutations. Because CDK4/6 pathway activation has been correlated with poor progression-free survival in melanoma patients treated with BRAFi combined with MEKi, we tested the combination of VS-6766 with the CDK4/6 inhibitor abemaciclib. We found that VS-6766 was synergistic with abemaciclib in reducing viability of melanoma cell lines. Additional combinations with VS-6766 are currently being tested and will be reported. These preclinical data support clinical testing of VS-6766 in rational combinations for treatment of cutaneous melanoma with BRAF, NRAS, NF1 or CRAF mutations. In clinical trials, a recommended phase 2 dose has been defined for the combination of VS-6766 with everolimus. Citation Format: Antonella Bacchiocchi, Silvia Coma, Sanjib Chowdhury, Mario Sznol, Ruth Halaban, Jonathan A. Pachter. Rational combinations with the dual RAF/MEK inhibitor VS-6766 for treatment of cutaneous melanoma harboring BRAF, NRAS, NF1 or CRAF mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1179.

Abstract 298: Targeting KRAS mutant non-small cell lung cancer with EGFR aptamer displaying 3WJ pRNA nanoparticles

Abstract Background and Purpose: KRAS mutations are one of the most common oncogenic mutations in human cancers, including non-small cell lung cancer (NSCLC), and have established roles in cancer pathogenesis and therapeutic resistance. Development of effective inhibitors of mutant KRAS represent a significant challenge. The field of three-way junction (3WJ) based RNA nanoparticles has advanced rapidly and shows promise as an effective in vivo siRNA delivery system. This aim of this study is to explore the potential of 3WJ-pRNA nanoparticles for specific and efficient delivery of KRASG12C siRNA to NSCLC cells harboring a KRASG12C mutation to effectively silence KRAS oncogenic activity. Experimental design: Multifunctional EGFRapt-3WJ-siKRASG12C nanoparticles were prepared using bottom-up self-assembly approach, and characterized by agarose gel shift assay, dynamic light scattering (DLS), and temperature gradient gel electrophoresis system (TGGE). Three NSCLC cell lines, H2122 and H2030 carrying KRASG12C, and H1299 with wild type KRAS were used in this study. Binding specificity and delivery efficiency of EGFRapt-3WJ-siKRASG12C nanoparticles in NSCLC cells were evaluated in vitro and in vivo. Biological effects of KRAS mutant silencing were assessed by in vitro functional assays, and in vivo tumor xenograft experiments. Results: Characterization of EGFRapt-3WJ-siKRASG12C by DLS showed 7.2 ± 0.5 nm average size, and TGGE indicated a melting temperature (Tm) of 51.77°C. Flow cytometry, IVIS lumina imaging assay, real-time quantitative PCR, western blot, and KRAS activity assay confirmed that EGFRapt-3WJ-siKRASG12C potently and selectively depleted cellular KRAS expression, resulting in suppression of downstream MAPK pathway signaling in KRASG12C NSCLC cells and in heterotopic tumor models. In addition, in vitro cell proliferation, migration/invasion, and chemotherapy and radiotherapy sensitivity assays, demonstrated that KRAS silencing by EGFRapt-3WJ-siKRASG12C suppressed NSCLC cell growth, migration/invasion ability, and sensitized NSCLC cells to chemotherapy or radiotherapy. In vivo, these nanoparticles led to regression of tumor growth in heterotopic models. Conclusions: Together, this study suggests that 3WJ pRNA based platform has clinical potential to suppress mutant KRAS activity for the treatment of KRAS driven human cancers, and warrants further development. Citation Format: Linlin Yang, Zhefeng Li, Peixuan Guo, Terence M. Williams. Targeting KRAS mutant non-small cell lung cancer with EGFR aptamer displaying 3WJ pRNA nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 298.