KRAS G12C Research Articles

TMIC-08. PATTERNS OF PSTAT3 EXPRESSION IN REACTIVE ASTROCYTES OF BRAIN METASTASES FROM NON-SMALL CELL LUNG CANCER AND CORRELATIONS WITH OUTCOME

Abstract BACKGROUND pSTAT3 expression in peritumoral reactive astrocytes (RA) of brain metastases (BM) from breast cancer may favor a pro-metastatic environment and negatively affect the intracranial progression-free survival (i-PFS) (Pellerino, 2023). We aim to evaluate whether pSTAT3 plays the same role also in BM from NSCLC. MATERIAL AND METHODS Seventy-two BM specimens from NSCLC were identified from the biobank of Pathology Unit of University of Turin and Berlin. STAT3 expression was scored in RA of peritumoral tissue according to Priego et al. (Nat Med 2018). Clinical and molecular data, and i-PFS were retrospectively retrieved. RESULTS Median age was 64 years (IC95% 59-67). Immunohistochemistry for GFAP and pSTAT3 was feasible in 66/72 (91,6%). 42/66 (63,6%) had BM with druggable mutations, while 24/66 (36,4%) did not show any actionable mutations. Druggable mutations were as follows: 8/42 (19,1%) KRAS G12C, 6/42 (14,3%) EGFR, 5/42 (11,9%) ALK, 1/42 (2,4%) BRAFv600E, 31/42 (73,8%) PDL1 expression. Overall, 53/66 (80,3%) showed positive staining of pSTAT3: 22/66 (33,3%) with score 3, 21/66 (31,8%) with 2, 10/66 (15,1%) with 1, and 12/66 (19.8%) with 0 (negative). High pSTAT3 expression (score 2-3) was observed in 32/42 (76,2%) BM with actionable mutations and in 12/24 (50%) without actionable mutations (p 0,031). PDL1 expression was significantly correlated with high pSTAT3 expression (29/31, 93,5%), while most of BM without PDL1 (20/35 – 57,1%) had low or absent pSTAT3 (score 0-1) (p<0,0001). Median i-PFS was 12 months (IC95% 8-23): low pSTAT3 BM had a median i-PFS of 18 months (IC95% 14-28) versus 9 months (IC95% 8-12) for high pSTAT3 BM (HR 5,3;p 0,0001). CONCLUSION pSTAT3 overexpression in RA is associated with PDL1 expression and may negatively impact the i-PFS in BM from NSCLC. These data support the investigation of STAT3 inhibitor silibinin in preventing intracranial recurrence in a clinical trial (NCT05689619).

Redefining pancreatic cancer management with tumor-agnostic precision medicine.

Precision oncology and tumor-agnostic drug development provide hope for enhancing outcomes among patients with pancreatic cancer. Tumor-agnostic therapies have emerged across various tumor types, driven by insights into shared biomarkers. In the case of pancreatic cancer, the prevalence of the KRAS gene mutation is noteworthy. However, there exist other actionable alterations, such as BRCA1/2 mutations and fusion genes (BRAF, FGFR2, RET, NTRK, NRG1, and ALK), which present potential targets for therapy. Notably, tumor-agnostic drugs have demonstrated efficacy in specific subsets of pancreatic cancer patients who harbor these genetic alterations. Despite the rarity of NTRK fusions in pancreatic cancer, larotrectinib and entrectinib have exhibited effectiveness in NTRK fusion-positive pancreatic cancers. Additionally, repotrectinib, a next-generation NTRK inhibitor, has shown promising activity in NTRK positive pancreatic cancer patients who have developed acquired resistance to previous NTRK inhibitors. Immune checkpoint inhibitors, such as pembrolizumab and dostarlimab, have proven to be effective in dMMR/MSI-H pancreatic cancers. Moreover, targeted therapies for BRAF V600, RET fusions, and HER2/neu overexpression have displayed promising results in specific subsets of pancreatic cancer patients. Emerging targets like NRG fusions, FGFR2 fusions, TP53 mutations, and KRAS G12C mutations present potential avenues for targeted therapy. Tumor-agnostic therapies have the potential to revolutionize pancreatic cancer treatment by focusing on specific genetic alterations. It is crucial to continue implementing comprehensive screening strategies that encompass the ability to detect all these tumor-agnostic biomarkers. This will be essential in identifying pancreatic cancer patients who may benefit from these therapies.

KRAS G12C mutation in NSCLC in a small genetic center: insights into sotorasib therapy response potential

Lung cancer remains a significant health challenge, characterized by aberrant tissue growth within the pulmonary system. Early carcinogenic events often involve genomic instability and the emergence of a mutator phenotype. In this study, we aimed to explore the mutator phenotype in 89 patients diagnosed with non-small-cell lung cancer (NSCLC). RNA isolation from formalin-fixed paraffin-embedded (FFPE) tissue samples was performed using the Promega ReliaPrep RNA Miniprep System, facilitating gene amplification relevant to cancer through the Archer® FusionPlexComprehensiveThyroid and Lung (CTL) kit. Next-generation sequencing (NGS) on the Illumina NextSeq platform enabled comprehensive analysis of target areas. Utilizing Archer Analysis software, secondary analyses involving data cleansing, alignment, and variant/fusion identification were executed against the human reference genome hg19 (GRCh37). Expression patterns were visualized using HeatMap graphics. Our findings revealed a notable presence of KRAS gene mutations in approximately 20% of NSCLC patients. Among these mutations, the G12C variant was predominant at 50%, followed by G12V and G12D variants at 11.2% each. Notably, patients harboring the G12C variant responded favorably to sotorasib medication. These results underscore the importance of mutational profiling and targeted therapeutic approaches in managing NSCLC, particularly highlighting the promising efficacy of sotorasib in G12C-mutated cases.

A novel label-free impedance biosensor for KRAS G12C mutations detection based on PET-RAFT and ROP synergistic signal amplification

The KRAS G12C mutations, as crucial biomarkers, are closely associated with non-small cell lung cancer. Here, a novel label-free electrochemical biosensor with synergistic signal amplification of photocell energy transfer-reversible addition fragmentation chain transfer (PET-RAFT) and ring-opening polymerization (ROP) was developed for the first time for sensitive detection of KRAS G12C mutations. Specifically, hairpin DNA (hDNA), which act as biomolecular probe, was self-assembled on Au electrode surface by Au-S bond. 4-cyano-4-[(dodecylsulfanylthiocarbonyl) sulfanyl] pentanoic acid (CDTPA), the chain transfer agent of PET-RAFT reaction, was then attached to hDNA via amide bond. After that, the target DNA (tDNA) was captured on the electrode surface by complementary base pairing with hDNA. Subsequently, large numbers of electro-active monomers N-acryloxysuccinimide (NAS) were successfully grafted to the electrode surface via PET-RAFT reaction, which provided plenty of junction sites for doxorubicin-polycaprolactone (Dox-PCL) synthesized by ROP. Finally, the Dox-PCL was connected to the electrode surface by ester bond, significantly amplifying the electrochemical signal. Under optimized conditions, the biosensor has a wide linear detection range of 0.1 pM to 1 μM, with a detection limit of 86.9 fM. Attribute to its high sensitivity, specificity, reproducibility and stability, this biosensor possesses considerable potential in early diagnosis of disease and biomedical research.

Comparative Efficacy of Adagrasib and Sotorasib in KRAS G12C-Mutant NSCLC: Insights from Pivotal Trials.

Background: The KRAS G12C mutation, prevalent in various malignancies, including non-small cell lung cancer (NSCLC), represents a unique therapeutic target. Adagrasib and sotorasib, two FDA-approved agents specifically targeting this mutation, have shown promise in clinical trials. This study aims to compare their efficacy in treating KRAS G12C-mutated NSCLC, drawing insights from pivotal clinical trials. Methods: We analyzed data from three key clinical trials: KRYSTAL-1, CodeBreak100, and CodeBreak200. Our methodology involved reconstructing individual patient data from published Kaplan-Meier curves using the IPDfromKM tool (Version 0.1.10). The primary endpoints were progression-free survival (PFS) and overall survival (OS), evaluated through hazard ratios (HRs) and the restricted mean survival time (RMST) method. Results: The HR for PFS favored adagrasib (HR: 0.90 [95% CI: 0.69, 1.19], p = 0.473), suggesting a non-significant trend toward better disease control compared to sotorasib. For OS, the HR was 0.99 [95% CI: 0.75, 1.33] (p = 0.969), indicating no significant difference between the two drugs. RMST analysis supported these findings, with adagrasib showing a consistently higher RMST in PFS at 6, 12, and 18 months. However, OS benefits converged over time, with adagrasib marginally surpassing sotorasib by the 18-month mark. Conclusions: This comprehensive analysis reveals that while adagrasib may offer a slight advantage in PFS, both drugs demonstrate comparable efficacy in OS for KRAS G12C-mutated NSCLC. The subtle differences observed, particularly in PFS, could inform clinical decision-making, emphasizing the need for personalized treatment strategies. Future research should focus on long-term effects and identifying patient subgroups that may benefit more from one drug over the other.

AMG 193, a Clinical Stage MTA-Cooperative PRMT5 Inhibitor, Drives Antitumor Activity Preclinically and in Patients With MTAP-Deleted Cancers.

One of the most robust synthetic lethal interactions observed in multiple functional genomic screens has been dependency on PRMT5 in cancer cells with MTAP deletion. We report the discovery of the clinical stage MTA-cooperative PRMT5 inhibitor AMG 193, which preferentially binds PRMT5 in the presence of MTA and has potent biochemical and cellular activity in MTAP-deleted cells across multiple cancer lineages. In vitro, PRMT5 inhibition induces DNA damage, cell cycle arrest, and aberrant alternative mRNA splicing in MTAP-deleted cells. In human cell line and patient-derived xenograft models, AMG 193 induces robust antitumor activity and is well tolerated with no impact on normal hematopoietic cell lineages. AMG 193 synergizes with chemotherapies or the KRAS G12C inhibitor sotorasib in vitro, and combination treatment in vivo significantly inhibits tumor growth. AMG 193 is demonstrating promising clinical activity, including confirmed partial responses in patients with MTAP-deleted solid tumors from an ongoing phase 1/2 study.

Comprehensive liquid biopsy analysis for monitoring NSCLC patients under second-line osimertinib treatment.

The heterogeneous and complex genetic landscape of NSCLC impacts the clinical outcomes of patients who will eventually develop resistance to osimertinib. Liquid biopsy (LB) analysis as a minimally invasive approach is a key step to efficiently identify resistance mechanisms and adjust to proper subsequent treatments. In the present study, we combined plasma-cfDNA and CTC analysis from 30 NSCLC patients in samples collected before treatment and at the progression of disease (PD). We detected molecular alterations at the DNA mutation (EGFR, PIK3CA, KRAS G12C, BRAF V600E), DNA methylation (RASSF1A, BRMS1, FOXA1, SLFN1, SHISA3, RARβ,, WIF-1, RASSF10 and APC), gene expression (CK-19, CK-18, CK-8, AXL, TWIST-1, PD-L1, PIM-1, Vimentin, ALDH-1, and B2M) and chromosomal level (HER2 and MET amplification) as possible resistance mechanisms and druggable targets. We also studied the expression of PD-L1 in single CTCs using immunofluorescence. In some cases, T790M resistance EGFR mutation was detected at baseline in CTCs but not in the corresponding plasma cfDNA. PIK3CA mutations were detected only in plasma-cfDNA but not in corresponding CTCs. KRAS G12C and BRAF V600E mutations were not detected in the samples analyzed. MET amplification was detected in the CTCs of two patients before treatment whereas HER2 amplification was detected in the CTCs of three patients at baseline and in one patient at PD. DNA methylation analysis revealed low concordance between CTCs and cfDNA, indicating the complementary information obtained through parallel LB analysis. Results from gene expression analysis indicated high rates of vimentin-positive CTCs detected at all time points during osimertinib. Moreover, there was an increased number of NSCLC patients at PD harboring CTCs positive in PD-L1. AXL and PIM-1 expression detected in CTCs during treatment suggesting new possible therapeutic strategies. Our results reveal that comprehensive liquid biopsy analysis can efficiently represent the heterogeneous molecular landscape and provide prominent information on subsequent treatments for NSCLC patients at PD since druggable molecular alterations were detected in CTCs.

OA14.05 KRAS G12C Inhibitor IBI351 In Patients (pts) with Advanced Non-Small Cell Lung Cancer (NSCLC): Updated Results from a Pivotal Phase 2 Study

OA14.05 KRAS G12C Inhibitor IBI351 In Patients (pts) with Advanced Non-Small Cell Lung Cancer (NSCLC): Updated Results from a Pivotal Phase 2 Study

Multigene Panel Next-Generation Sequencing Techniques in the Management of Patients with Metastatic Colorectal Carcinoma: The Way Forward for Personalized Treatment? A Single-Center Experience

The efficacy and cost-effectiveness of Multigene Panel Next-Generation Sequencing (NGS) in directing patients towards genomically matched therapies remain uncertain. This study investigated metastatic colorectal cancer (mCRC) patients who underwent NGS analysis on formalin-fixed paraffin-embedded tumor samples. Data from 179 patients were analyzed, revealing no mutations in 39 patients (21.8%), one mutation in 83 patients (46.4%), and two or more mutations in 57 patients (31.8%). KRAS mutations were found in 87 patients (48.6%), including KRAS G12C mutations in 5 patients (2.8%), PIK3CA mutations in 40 patients (22.4%), and BRAF mutations in 26 patients (14.5%). Less common mutations were identified: ERBB2 in five patients (2.8%) and SMO in four patients (2.2%). Additionally, MAP2K1, CTNNB1, and MYC were mutated in three patients (2.4%). Two mutations (1.1%) were observed in ERBB3, RAF1, MTOR, JAK1, and FGFR2. No significant survival differences were observed based on number of mutations. In total, 40% of patients had druggable molecular alterations, but only 1.1% received genomically guided treatment, suggesting limited application in standard practice. Despite this, expanded gene panel testing can identify actionable mutations, aiding personalized treatment strategies in metastatic CRC, although current eligibility for biomarker-guided trials remains limited.

An updated overview of K-RAS G12C inhibitors in advanced stage non-small cell lung cancer.

The discovery of KRAS mutations, particularly the KRASG12C variant, has been a milestone in understanding the molecular underpinnings of non-small cell lung cancer (NSCLC). These mutations are associated with aggressive tumor behavior and resistance to conventional therapies, highlighting the urgent need for targeted interventions. In this comprehensive review, we analyze the advancements in KRAS G12C inhibitors for the treatment of non-small cell lung cancer. Literature search is made from PubMed, Medline ASCO and ESMO Annual Meetings abstracts by using the following search keywords: "sotorasib", "adagrasib", "divarasib" and "KRAS G12C inhibitors." The last search was on 5June 2024. This review highlights the importance of pharmacokinetics, pharmacodynamics and potential adverse effects for treating individual patients and ensuring the best outcomes. Additionally, the review discusses research identifying biomarkers that can predict therapy responses and mentions the combination strategies to overcome resistance. Results of the studies and ongoing clinical trials are also briefly summarized in this review. KRASG12C inhibitors sotorasib, adagrasib and the newer divarasib, has revolutionized treating patients harboring this mutation. Ongoing studies and future clinical trials will refine our understandings with the ultimate goal of improving survival and quality of life for patients with this challenging disease.

312 (PB300): Concurrent inhibition of KRAS G12C and ERK1/2 overcomes acquired resistance to KRAS G12C inhibitors (G12Cis) conferred by various genetic alterations

312 (PB300): Concurrent inhibition of KRAS G12C and ERK1/2 overcomes acquired resistance to KRAS G12C inhibitors (G12Cis) conferred by various genetic alterations

Brief Report: Not Created Equal: Survival Differences by KRAS Mutation Subtype in NSCLC Treated With Immunotherapy

IntroductionThe predictive and prognostic implications of different KRAS mutation (KRASm) subtypes in metastatic NSCLC have not been clearly defined. We used a nationwide observational database to investigate whether KRASm subtypes differ in their association with survival in metastatic NSCLC treated with immune checkpoint inhibitor (ICI)-based therapy, across programmed death-ligand 1 (PD-L1) levels. MethodsPatients with advanced nonsquamous NSCLC who initiated first-line ICI-based therapy from 2016 to 2021 and had known PD-L1 expression and comprehensive genomic profiling including KRAS, STK11, KEAP1, and TP53 were included. Within PD-L1 expression subgroups (<1%, 1%–49%, ≥50%), Cox multivariable regression was used to evaluate the association between KRASm subtypes (G12C, G12V, G12D, other KRASm) and overall survival, estimated using Kaplan-Meier methodology. ResultsAmong the 1539 patients, 819 patients were KRAS wild type (KRASwt) and 720 were KRASm (296 KRAS G12C, 143 KRAS G12V, 97 KRAS G12D, 184 other KRASm). In the 50% or higher PD-L1 subgroup, patients with KRAS G12V had worse survival (median overall survival [mOS] = 8.2 mo) compared with KRASwt (mOS = 13.3 mo) and other KRAS subgroups (mOS ranging from 13.4 to 19.9 mo). On adjusted Cox multivariable regression in the 50% or higher PD-L1 subgroup, the hazard ratio for death for KRAS G12V ranged from 1.53 to 1.78 compared with KRASwt and other KRASm subtypes (all p < 0.05). ConclusionsAlthough patients with 50% or higher PD-L1 with KRAS G12C, G12D, and other subtypes exhibited similar survival to KRASwt, KRAS G12V was associated with significantly worse survival than KRASwt and other KRASm subtypes. All KRASm should not be regarded as uniform predictors of ICI responsiveness, even with high PD-L1 expression; KRAS G12V tumors may have worse outcomes with ICI-based therapy and benefit from treatment intensification.

388 (PB376): KO-2806, a next-generation farnesyl transferase inhibitor, re-sensitizes KRAS G12C NSCLC tumors to KRAS G12C mutant-specific inhibitors through mTOR signaling inhibition

388 (PB376): KO-2806, a next-generation farnesyl transferase inhibitor, re-sensitizes KRAS G12C NSCLC tumors to KRAS G12C mutant-specific inhibitors through mTOR signaling inhibition

274 (PB262): Development of Patient-Derived Colorectal Cancer Xenograft and Organoid Models with Acquired Resistance to KRAS G12C Inhibitors

274 (PB262): Development of Patient-Derived Colorectal Cancer Xenograft and Organoid Models with Acquired Resistance to KRAS G12C Inhibitors

Molecular Profiling of Low-Grade Appendiceal Mucinous Neoplasms (LAMN).

Low-grade appendiceal mucinous neoplasia (LAMN) represents a relatively rare tumor of the appendix typically diagnosed incidentally through appendectomy for acute appendicitis. In cases where perforation occurs, mucinous content may disseminate into the abdominal cavity, leading to the development of pseudomyxoma peritonei (PMP). The primary objective of this study was to elucidate the molecular characteristics associated with various stages of LAMN and PMP. DNA was extracted from LAMN, primary PMPs, recurrent PMPs, and adenocarcinomas originating from LAMN. The subsequent analysis involved the examination of mutational hotspot regions within 50 cancer-related genes, covering over 2800 COSMIC mutations, utilizing amplicon-based next-generation sequencing (NGS). Our findings revealed activating somatic mutations within the MAPK-signaling pathway across all tumors examined. Specifically, 98.1% of cases showed mutations in KRAS, while one tumor harbored a BRAF mutation. Additionally, GNAS mutations were identified in 55.8% of tumors, with no significant difference observed between LAMN and PMP. While LAMN rarely displayed additional mutations, 42% of primary PMPs and 60% of recurrent PMPs showed additional mutations. Notably, both adenocarcinomas originating from LAMN showed mutations within TP53. Furthermore, 7.7% (4/52) of cases exhibited a potentially targetable KRAS G12C mutation. In four patients, NGS analysis was performed on both primary PMP and recurrent PMP/adenocarcinoma samples. While mutations in KRAS and GNAS were detected in almost all samples, 50% of recurrent cases displayed an additional SMAD4 mutation, suggesting a notable alteration during disease progression. Our findings indicate two key points: First, mutations within the MAPK pathway, particularly in KRAS, are evident across all tumors, along with a high frequency of GNAS mutations. Second, progression toward PMP or adenocarcinoma is associated with an accumulation of additional mutations within common oncogenic pathways.

Clinical utility of upfront liquid biopsy in non-small cell lung cancer in the community setting.

316 Background: Molecular diagnosis of advanced non-small cell lung cancer (NSCLC) is critical to guide therapeutic decisions. Blood next generation sequencing (NGS) allows for non-invasive screening for targetable genetic abnormalities. Many studies have validated using the liquid biopsies to screen for resistant mutations at the emergence of treatment failure. However, the clinical utility of liquid biopsy for newly diagnosed NSCLC, as part of a comprehensive molecular profiling, is an area of active research. Methods: Retrospective analysis of the molecular landscape and clinical outcomes in NSCLC patients who had liquid biopsy done between December of 2017 to February of 2022. Patients had EGFR, ALK, ROS-1, and BRAF tested in the tissue, and underwent liquid biopsy for broad molecular profiling. The plasma genotyping was conducted using a 73-gene panel by Guardant 360 test. Actionable mutations were stratified accordingly to the OncoKB database based on the level of preclinical and clinical evidence of drug targetability. Survival analysis was conducted by August of 2023. Results: We enrolled 122 NSCLC patients who 84% were treatment-naïve and 78% had the liquid biopsy performed at the initial diagnosis. We found that 86 patients had oncogenic mutations and 43 (35%) had actionable mutations, with 37 (29%) falling under level 1 of evidence mutations. EGFR and KRAS G12C mutations were the two most common level 1 genetic abnormalities (23% and 11% of all actionable mutations, respectively). We identified two germline BRCA carriers who were referred for genetic counselling. 25 patients (20%) received treatment based on the liquid biopsy results, with 15 (12%) achieving partial response. Six patients had liquid biopsy done at progression of EGFR or MET therapies, which identified a resistance mechanism in three of them. Conclusions: Upfront liquid biopsy identified a significant proportion of patients with targetable mutations. Here, we reported actionable mutations in 35% of our patients who 84% had no prior systemic treatment. Our results complement prior literature and shows that blood next generation sequencing can be a useful tool to guide upfront therapeutical options at the community healthcare setting.

Adagrasib in KRYSTAL-12has Broken the KRAS G12C Enigma Code in Non-Small Cell Lung Carcinoma.

Kirsten rat sarcoma viral oncogene homolog (KRAS) G12C-mutant non-small cell lung carcinoma (NSCLC) accounts for approximately 10-13% of advanced nonsquamous NSCLC cases in Western populations, presenting a significant therapeutic challenge owing to the difficulty of directly targeting KRAS. Adagrasib, an oral small-molecule covalent inhibitor, irreversibly and selectively targets KRASG12C in its inactive state. It received accelerated Food and Drug Administration (FDA) approval on December 12, 2022, following the KRYSTAL-1 Phase II trial. The Phase III KRYSTAL-12 trial demonstrated that adagrasib significantly improved median progression-free survival (mPFS) compared with docetaxel (HR, 0.58; 95% CI: 0.45-0.76; P<0.0001) and increased the intracranial objective response rate (ORR) to 40% in the central nervous system (CNS) evaluable population. This paper evaluates the clinical efficacy of adagrasib in KRAS G12C-mutated advanced NSCLC discussing its potential advantages over other inhibitors such as sotorasib. Despite not reaching the 6-month mPFS benchmark, adagrasib offers significant clinical benefits, particularly for the management of CNS metastases. In this pros and cons debate, we argue that adagrasib has broken the KRAS G12C enigma code in NSCLC.

EP.12C.01 Sotorasib vs Adagrasib: Matching-adjusted Indirect Comparison in Prior Treated KRAS G12C Advanced Non-Small Cell Lung Cancer

EP.12C.01 Sotorasib vs Adagrasib: Matching-adjusted Indirect Comparison in Prior Treated KRAS G12C Advanced Non-Small Cell Lung Cancer

EP.12C.03 Toxicities Associated with Immune Checkpoint Inhibitors Followed by KRAS G12C Inhibitors in Patients with Metastatic NSCLC

EP.12C.03 Toxicities Associated with Immune Checkpoint Inhibitors Followed by KRAS G12C Inhibitors in Patients with Metastatic NSCLC

Brief Report: Phase II Trial of Regorafenib and Oral Methotrexate in Previously Treated Advanced KRAS-Mutant NSCLC

IntroductionThere are no standard targeted treatment options for advanced KRAS-mutant NSCLC beyond KRAS G12C inhibitors. A computational model identified regorafenib and low-dose methotrexate as synergistic in preclinical models of KRAS-mutant NSCLC. This study evaluated the efficacy and safety of the combination in previously treated advanced KRAS-mutant NSCLC. MethodsThis single-arm phase II study included regorafenib 80 to 120 mg daily and oral methotrexate dose escalated to tolerability from 10 to 20 mg twice weekly during the first cycle. Both agents were administered on weeks 1 to 3 of each 4-week cycle. The primary end point was progression-free survival. ResultsIn total, 18 patients with KRAS-mutant NSCLC were enrolled. Five patients received regorafenib at a 120 mg starting dose with four discontinuing due to toxicity; subsequently, 13 patients were treated at an 80 mg starting dose, with eight dose-escalating to 120 mg after the first cycle. Median progression-free survival was 3.7 months (95% confidence interval 1.8–8.6) and median overall survival was 10.4 months (95% confidence interval 5.2–30.3). The objective response rate was 16.7% and the 8-week disease control rate was 66.7%. Grade 3 treatment-related adverse events occurred in 11 patients, most often oral mucositis (n = 2) and asymptomatic lipase increase (n = 2). One patient developed asymptomatic grade 4 lipase increase. ConclusionsCombination treatment of regorafenib and oral methotrexate in patients with KRAS-mutant NSCLC was limited due to toxicity, and the study did not meet its primary end point. Computational modeling may aid in repurposing therapeutic options though caution must be exercised with tolerability.