KRAS Mutant NSCLC Research Articles

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.

213 (PB201): MYC Inhibition by OMO-103 Reprograms Tumor Immunity and Enhances Immunotherapy Efficacy in KRAS Mutant NSCLC

213 (PB201): MYC Inhibition by OMO-103 Reprograms Tumor Immunity and Enhances Immunotherapy Efficacy in KRAS Mutant NSCLC

Efficacy and safety of olomorasib (LY3537982), a second-generation KRAS G12C inhibitor (G12Ci), in combination with pembrolizumab in patients with KRAS G12C-mutant advanced NSCLC.

195 Background: While immunotherapy (IO) is established as the cornerstone of first-line treatment for KRAS-mutant NSCLC, outcomes remain suboptimal. Further progress may be achieved with the addition of targeted therapy to IO, an established first-line paradigm in some other cancer types (RCC), but historically challenging in NSCLC. Here, we study pembrolizumab plus olomorasib, a potent and highly selective second-generation inhibitor of GDP-bound KRAS G12C, in NSCLC patients treated on LOXO-RAS-20001, a phase 1/2 study of olomorasib in KRAS G12C-mutant solid tumors (NCT04956640). Methods: Patients (pts) with advanced KRAS G12C mutant NSCLC (tissue or plasma) in any treatment line, including prior KRAS G12Ci and/or prior IO were eligible. Dose escalation of olomorasib plus pembrolizumab followed a mTPI-2 method. Safety was evaluated across all pts dosed with the combination. Antitumor activity per RECIST v1.1 was studied in all pts who had ≥1 post-baseline response assessment (PBRA) or had discontinued before the first PBRA. Results: As of 30 October 2023, 50 pts with advanced NSCLC received 50-150 mg BID PO olomorasib plus 200 mg Q3W pembrolizumab. Median age was 66 yrs (range, 42-83), median number of prior systemic therapies was 2 (range, 0-8), and 34% had received a prior KRAS G12Ci. During escalation, 2 of 6 ptstreated at 150 mg BID developed grade ³3 LFTs, precluding further evaluation of this dose. In 44 pts treated at 50 or 100 mg BID, TRAEs ≥10% (related to olomorasib and/or pembrolizumab) were diarrhea (30%), ALT increased (20%), AST increased (18%), fatigue (14%), nausea (14%) and pruritus (11%); grade 3 TRAEs in ≥10% of pts were diarrhea (16%); pneumonitis was seen in 3 pts (grades 2/3/4). TRAEs led to olomorasib dose reduction in 14% of pts, olomorasib dose hold in 27%, and pembrolizumab dose hold in 18%. Due to TRAEs, 9% of pts discontinued olomorasib or pembrolizumab and 9% discontinued both. 27 pts remain on treatment, and 17 discontinued treatment (10 due to PD, 4 due to AE). Among the 30 efficacy evaluable KRAS G12Ci-naïve pts (60% IO pre-treated, 60% chemotherapy pre-treated), at a median follow-up of 6 months (95% CI, 4-7) ORR was 63% (15 PR, 4 unconfirmed PR pending/ongoing; 95% CI, 44-80) and DCR was 93% (28/30; 95% CI, 78-99); the median PFS was not estimable (95% CI, 5-NE); ORR was 75% (9/12) in PD-L1 ≥50%, 56% (10/18) in PD-L1 <50%/unknown (3 pts PD-L1 unavailable). In 9 first-line pts, ORR was 78% (6 PR, 1 unconfirmed PR pending/ongoing; 95% CI, 40-97) and DCR was 100%. Conclusions: Olomorasib (50 or 100 mg BID) in combination with pembrolizumab demonstrated favorable safety and antitumor activity in pts with KRAS G12C-mutant advanced NSCLC, supporting further development in first-line NSCLC. A global, registrational study investigating this combination in first-line NSCLC is currently enrolling (SUNRAY-01, NCT06119581). Clinical trial information: NCT04956640 .

Efficacy and safety of olomorasib (LY3537982), a second-generation KRAS G12C inhibitor (G12Ci), in combination with pembrolizumab in patients with KRAS G12C-mutant advanced NSCLC.

8510 Background: While immunotherapy (IO) is established as the cornerstone of first-line treatment for KRAS-mutant NSCLC, outcomes remain suboptimal. Further progress may be achieved with the addition of targeted therapy to IO, an established first-line paradigm in some other cancer types (RCC), but historically challenging in NSCLC. Here, we study pembrolizumab plus olomorasib, a potent and highly selective second-generation inhibitor of GDP-bound KRAS G12C, in NSCLC patients treated on LOXO-RAS-20001, a phase 1/2 study of olomorasib in KRAS G12C-mutant solid tumors (NCT04956640). Methods: Patients (pts) with advanced KRAS G12C mutant NSCLC (tissue or plasma) in any treatment line, including prior KRAS G12Ci and/or prior IO were eligible. Dose escalation of olomorasib plus pembrolizumab followed a mTPI-2 method. Safety was evaluated across all pts dosed with the combination. Antitumor activity per RECIST v1.1 was studied in all pts who had ≥1 post-baseline response assessment (PBRA) or had discontinued before the first PBRA. Results: As of 30 October 2023, 50 pts with advanced NSCLC received 50-150 mg BID PO olomorasib plus 200 mg Q3W pembrolizumab. Median age was 66 yrs (range, 42-83), median number of prior systemic therapies was 2 (range, 0-8), and 34% had received a prior KRAS G12Ci. During escalation, 2 of 6 ptstreated at 150 mg BID developed grade ≥3 LFTs, precluding further evaluation of this dose. In 44 pts treated at 50 or 100 mg BID, TRAEs ≥10% (related to olomorasib and/or pembrolizumab) were diarrhea (30%), ALT increased (20%), AST increased (18%), fatigue (14%), nausea (14%) and pruritus (11%); grade 3 TRAEs in ≥10% of pts were diarrhea (16%); pneumonitis was seen in 3 pts (grades 2/3/4). TRAEs led to olomorasib dose reduction in 14% of pts, olomorasib dose hold in 27%, and pembrolizumab dose hold in 18%. Due to TRAEs, 9% of pts discontinued olomorasib or pembrolizumab and 9% discontinued both. 27 pts remain on treatment, and 17 discontinued treatment (10 due to PD, 4 due to AE). Among the 30 efficacy evaluable KRAS G12Ci-naïve pts (60% IO pre-treated, 60% chemotherapy pre-treated), at a median follow-up of 6 months (95% CI, 4-7) ORR was 63% (15 PR, 4 unconfirmed PR pending/ongoing; 95% CI, 44-80) and DCR was 93% (28/30; 95% CI, 78-99); the median PFS was not estimable (95% CI, 5-NE); ORR was 75% (9/12) in PD-L1 ≥50%, 56% (10/18) in PD-L1 < 50%/unknown (3 pts PD-L1 unavailable). In 9 first-line pts, ORR was 78% (6 PR, 1 unconfirmed PR pending/ongoing; 95% CI, 40-97) and DCR was 100%. Conclusions: Olomorasib (50 or 100 mg BID) in combination with pembrolizumab demonstrated favorable safety and antitumor activity in pts with KRAS G12C-mutant advanced NSCLC, supporting further development in first-line NSCLC. A global, registrational study investigating this combination in first-line NSCLC is currently enrolling (SUNRAY-01, NCT06119581). Clinical trial information: NCT04956640 .

Epithelial-mesenchymal transition status is a remarkable biomarker for the combination treatment with avutometinib and defactinib in KRAS-mutated non-small cell lung cancer.

Recent therapeutic strategies for KRAS-mutated cancers that inhibit the MAPK pathway have attracted considerable attention. The RAF/MEK clamp avutometinib (VS-6766/CH5126766/RO5126766/CKI27) is promising for patients with KRAS-mutated cancers. Although avutometinib monotherapy has shown clinical activity in patients with KRAS-mutated cancers, effective combination strategies will be important to develop. Using a phosphorylation kinase array kit, we explored the feedback mechanism of avutometinib in KRAS-mutated NSCLC cells, and investigated the efficacy of combining avutometinib with inhibitors of the feedback signal using in vitro and in vivo experiments. Moreover, we searched for a biomarker for the efficacy of combination therapy through an in vitro study and analysis using the The Cancer Genome Atlas Programme dataset. Focal adhesion kinase (FAK) phosphorylation/activation was increased after avutometinib treatment and synergy between avutometinib and FAK inhibitor, defactinib, was observed in KRAS-mutated NSCLC cells with an epithelial rather than mesenchymal phenotype. Combination therapy with avutometinib and defactinib induced apoptosis with upregulation of Bim in cancer cells with an epithelial phenotype in an in vitro and in vivo study. These results demonstrate that the epithelial-mesenchymal transition status may be a promising biomarker for the efficacy of combination therapy with avutometinib and defactinib in KRAS-mutated NSCLC.

Resistance to KRAS inhibition in advanced non-small cell lung cancer

Lung cancer remains the leading cause of cancer death globally. More than 50% of new cases are diagnosed in an advanced or metastatic stage, thus contributing to the poor survival of such patients. Mutations in the KRAS (Kirsten rat sarcoma virus) gene occur in nearly a third of lung adenocarcinoma and have for decades been deemed an ‘undruggable’ target. Yet, in recent years, a growing number of small molecules, such as the GTPase inhibitors, has been investigated in clinical trials of lung cancer patients harboring KRAS mutations, yielding promising results with improved outcomes. Currently, there are only two approved targeted therapies (adagrasib and sotorasib) for advanced or metastatic KRAS-mutated NSCLC from the second-line setting onwards. In this narrative review, we will focus on KRAS, its molecular basis, the role of its co-mutations, clinical evidence for its inhibition, putative mutation to resistance, and future strategies to overcome resistance to KRAS inhibition.

KRAS-mutated non-small cell lung cancer: new therapy strategies

Lung cancer remains one of the most dangerous and most common cancers, requiring constant improvement of diagnostic and treatment methods. The genetic heterogeneity of lung cancer forces us to search for new therapeutic targets in an attempt to achieve greater effectiveness for certain groups of patients. The purpose of the study was to update current knowledge about lung adenocarcinoma with a mutation in the KRAS gene, to consider new opportunities for personalized treatment of KRAS-mutated NSCLC and to form an image of a Russian patient who is potentially indicated for targeted therapy. Material and methods. A search of available literature sources published in the Pubmed, Cochrane Library, Elibrary database was carried out, publications covering the period from 2008 to 2023 were included. Results. The article discussed molecular genetic testing, including NGS next generation sequencing, and its role in determining the presence of KRAS gene mutations in patients with lung cancer. the effectiveness of targeted drugs, such as Sotorasib and Adagrasib was also discussed. The mechanism of action is aimed at suppressing the activity of the mutant KRAS G12C protein, which can significantly improve patient survival prognosis. We obtained data on the results of testing 935 patients with non-squamous non-small cell lung cancer from various medical centers in Russia. The KRAS gene mutation was identified in 160 (17.1 %) patients, of whom 96 (10.3 %) had KRAS G12C variant. The KRAS mutation was determined by PCR in 44 patients and by NGS (including on the FoundationOne platform) in 111 patients. Clinical characteristics, such as gender, age, smoking status, PD-L1 expression level, presence of co-mutations (TP53, STK11, KEAP1, were largely similar between patients from real-world clinical practice and patients included in the CodeBreak100 study. Conclusion. The research results confirm the high effectiveness of Sotorasib and Adagrasib for patients with the KRAS G12C mutation and open up new prospects in the treatment of lung cancer. The clinical data obtained from Russian patients demonstrate consistency with the patient profile from registration studies of these drugs. This once again demonstrates the need to expand the range of molecular genetic testing for timely identification of this group of patients and prescribing the most effective treatment for them.

Abstract 447: Anti-tumor efficacy of ompenaclid, a creatine transporter inhibitor, in KRAS mutant tumors, including NSCLC

Abstract Background: Pre-clinical studies identified creatine metabolism to be activated in KRAS mutant metastatic colorectal cancer (CRC) as a mechanism to fuel the increased energy demands of RAS mutant tumors. Metastatic colon cancer cells overexpress and subsequently release creatine kinase-B (CKB) into the extracellular space, where it phosphorylates creatine to generate the high energy metabolite phosphocreatine. Ompenaclid is a small molecule inhibitor of the creatine transporter SLC6A8. Inhibition of SLC6A8 by ompenaclid prevents import of phosphocreatine/creatine, resulting in depletion of intracellular creatine, phosphocreatine and ATP levels. This results in tumor apoptosis and robust anti-tumor efficacy in CRC models with a wide range of KRAS mutant alleles. Ompenaclid is currently in a Phase 2 trial, in combination with FOLFIRI and bevacizumab, in patients with RAS-mutated second-line advanced/metastatic colorectal cancer. Here, we assessed efficacy of ompenaclid in tumors beyond CRC, including KRAS WT and KRAS mutant NSCLC. Methods: Athymic mice were inoculated with CRC, pancreatic, gastric or NSCLC cancer cell lines and treated with ompenaclid once tumors reached ~150 mm3, until termination. Plasma metabolites were quantified by LC-MS/MS and tumoral expression of CKB and SLC6A8 in NSCLC and CRC tumors was measured by qPCR after treatment with a control or ompenaclid-supplemented diet for ~10 days. Combination treatment with MRTX849, a KRAS G12C inhibitor, was conducted in a pancreatic MiaPaca xenograft model. Results: Our studies demonstrate ompenaclid anti-tumor efficacy in NSCLC and pancreatic xenografts. Notably, and consistent with findings in CRC, efficacy in NSCLC was more robust in RAS mutant cancer models, relative to those bearing KRAS WT tumors. Metabolite analysis of the plasma of tumor-bearing mice at baseline revealed that mice harboring RAS mutant tumors had higher levels of p-creatine and lower levels of ATP, indicating that RAS mutant tumors utilize higher amounts of ATP, which may be converted to phosphocreatine by tumoral CKB, as confirmed by qPCR analysis. This finding is consistent with metastatic RAS mutant CRC tumors utilizing extracellular ATP to generate phosphocreatine and thus exhibiting greater dependency on creatine metabolism relative to RAS WT tumors. Treatment with ompenaclid also demonstrated additive efficacy in combination with KRAS G12C inhibitors. In summary, these data support development of ompenaclid in indications beyond CRC, including NSCLC, as well as in combination with KRAS G12C inhibitors. Citation Format: PuiChi Lo, Victor Sanz Chavez, Shugaku Takeda, Masoud Tavazoie, Isabel Kurth. Anti-tumor efficacy of ompenaclid, a creatine transporter inhibitor, in KRAS mutant tumors, including NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 447.

56P Prevalence, clinical characteristics, and treatment outcomes of patients with KRAS-mutated non-squamous NSCLC and PD-L1 expression: Real-life data analysis

56P Prevalence, clinical characteristics, and treatment outcomes of patients with KRAS-mutated non-squamous NSCLC and PD-L1 expression: Real-life data analysis

Plunging Into the PACIFIC: Outcomes of Patients With Unresectable KRAS-Mutated Non-Small Cell Lung Cancer Following Definitive Chemoradiation and Durvalumab Consolidation

BackgroundImmune checkpoint inhibitor (ICI) consolidation following concurrent chemoradiotherapy (CRT) substantially improved progression free survival (PFS) and overall survival (OS) in the PACIFIC trial becoming the standard of care in locally-advanced, unresectable NSCLC. KRAS mutation may influence response to ICI. MethodsIn this single-institution, retrospective analysis, we compared treatment outcomes for patients with unresectable KRAS mutated (KRAS-mt) and wild-type (KRAS-wt) NSCLC treated with CRT between October 2017 and December 2021. Kaplan–Meier analysis was conducted comparing median progression free survival and median overall survival from completion of radiotherapy in all KRAS-mt patients and KRAS-G12C-mutated patients. Outcomes were also compared with and without ICI consolidation. ResultsOf 156 patients, 42 (26.9%) were KRAS-mt and 114 (73.1%) were KRAS-wt. Baseline characteristics differed only in histology; KRAS-mt NSCLC more likely to be adenocarcinoma. KRAS-mt patients had worse PFS (median 6.3 vs. 10.7 months, P = .041) but similar OS (median 23.1 vs. 27.3 months, P = .237). KRAS-mt patients were more likely to not receive ICI due to rapid disease progression post-CRT (23.8% vs. 4.4%, P = .007). Among patients who received ICI (n = 114), KRAS-mt was not associated with inferior PFS (8.1 vs. 11.9 months, P = .355) or OS (30.5 vs. 31.7 months, P = .692). KRAS-G12C patients (n = 22) had similar PFS and OS to other KRAS-mt. ConclusionIn one of the largest post-CRT KRAS-mt cohort published, KRAS-mt was associated with inferior PFS, largely due to rapid progression prior to ICI consolidation, but did not affect OS. Among those who received ICI consolidation, outcomes were comparable regardless of KRAS-mt status.

Abstract A091: The class I selective, oral HDAC inhibitor bocodepsin enhances the response to MAPK pathway inhibitors in multiple tumor types with mutations in MAPK pathway signaling proteins

Abstract Activating MAPK pathway mutations, found in >30% of all human tumors, are frequently associated with poor outcomes. Several MAPK pathway targeted drugs are approved but single agent activity is modest, supporting the need for rational targeted combinations to improve outcomes. Multiple studies propose synthetic lethality between Class I HDAC inhibitors and MAPK pathway inhibitors in MAPK pathway mutated cancers, due to a combined effect of inhibiting double-stranded DNA repair and other survival pathways to drive apoptosis. The use of HDACi has been challenged by poor potency, selectivity, safety and convenience, highlighting the need for a better HDACi in the clinic. Bocodepsin, a potent class I-selective oral HDACi, is currently in a phase 1b/2 trial in combination with binimetinib in patients with NRAS mutant melanoma. The clinical profile shows exposure consistent with preclinical activity with strong pharmacodynamic activity at tolerated doses. OKI-005, a bocodepsin analog optimized for in vitro activity, produces the same active metabolite as bocodepsin. To explore the potential for broad application of bocodepsin combinations, we evaluated OKI-005 in combination with the MEK inhibitor binimetinib in a 72H in vitro proliferation screen of 89 cell lines covering a range of tumor types, MAPK pathway mutations, and co-mutations. Net cell killing with the combination vs. single agents was evaluated at clinically relevant doses. Combination activity was observed in tumor types that commonly harbor activating MAPK pathway mutations, including melanoma (6/13, 46%), pancreatic (3/5, 60%), lung (10/22, 45%) and colon (8/13, 62%). Among these, single agent binimetinib activity was observed in only 1/53. The combination response rate in colon cancer models was of note, as single agent MAPK pathway inhibitors are typically inactive in colon cancers. Activity was independent of the activating MAPK pathway mutation: combination activity was observed in lines with KRAS (13/24, 52%), NRAS (8/12, 67%) and BRAF (7/13, 54%) mutations. These findings translated to combinations with other MAPK inhibitors in vitro and in vivo. In vitro, OKI-005 exhibited enhanced activity in combination with KRAS inhibitors and with the ERK inhibitor GDC-0994. 25 of the 89 tumor lines were evaluated in combination with GDC-0994, and the profile of inhibition was identical to that with binimetinib. In vivo, the combination of binimetinib + bocodepsin led to 9/10 regressions in the NRAS mutant melanoma model SK-MEL-2, vs. 0/10 and 2/10 with binimetininb and bocodepsin, respectively. The combination of sotorasib + bocodepsin led to deeper regressions, vs. single agent sotorasib, in the KRAS mutant NSCLC model H358, and greater response in the KRAS mutant NSCLC model H2122. Combination activity was associated with increases in cleaved PARP and p-gH2AX, markers of DNA damage induction and apoptosis. These data demonstrate the potential for bocodepsin to synergize with MAPK pathway inhibitors across multiple indications in tumors that harbor MAPK pathway mutations. Citation Format: Rich Woessner, Maria Hoh, James Winkler, Tony Piscopio, Duncan Walker. The class I selective, oral HDAC inhibitor bocodepsin enhances the response to MAPK pathway inhibitors in multiple tumor types with mutations in MAPK pathway signaling proteins [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 A091.

Abstract C108: Enhanced growth inhibition in lung cancer cells through NBF-006 combination therapy with chemotherapy or KRAS inhibitors

Abstract Background: Glutathione-S-transferase P (GSTP) is strongly up-regulated in many cancer types, specifically KRAS-mutant lung and is also a known regulator of oncogenic MAPK and PI3K pathways. In cancer cells, overexpression of GSTP regulates apoptosis by inhibiting Jun-p53 complex in JNK pathway. NBF-006 is a novel lyophilized lipid nanoparticle formulation, encapsulating a small interfering ribonucleic acid (siRNA) designed to inhibit the expression of GSTP in lung tumors. NBF-006 has been very well tolerated with early signs of efficacy in NSCLC patients in a phase 1 dose escalation and expansion study. As NBF-006 is well tolerated and unlikely to have drug-drug interactions, combination strategies are currently being developed. Due to the detoxifying role of GSTP, combination with chemo agents used to treat NSCLC may increase the sensitivity of cancer cells resulting in apoptosis and/or reduced resistance. As GSTP and KRAS enhance tumor growth and survival, inhibition of GSTP and KRAS may be synergistic. Methods: Anti-tumor activity of GSTP siRNA (NDT-05-1040), when combined with chemo agents, KRAS inhibitors or immune cells was assessed in a panel of KRAS mutant NSCLC lines. For chemo agents and KRAS inhibitors, NDT-05-1040 combinations was evaluated using Combenefit software and Loewe model. Results: Combination of NDT-05-1040 with chemotherapy drugs including paclitaxel, gemcitabine, cisplatin, and pemetrexed controlled tumor cell growth significantly better than either NBF-006 alone or the chemo treatment alone. In A549, H1373, H358, and H1792 lines, at low doses paclitaxel combined with NDT-05-1040 and resulted in synergistic cell killing (Loewe scores >20). Gemcitabine & Cisplatin combination with NDT-05-1040 in H1373 cells further improved cell killing by 5-fold (Loewe scores >20). Pemetrexed combined with NDT-05-1040 and led to additive cell killing in A549 (Loewe score >10). Combination of NDT-05-1040 with KRASG12C inhibitors, Sotorasib & Adagrasib were conducted in H358, H1222, and MiaPaca-2. Cell viability assays demonstrated that the combination resulted in strong synergistic, anti-proliferative effects at low doses in H358 cells (the greatest Loewe scores for Adagrasib and Sotorasib: 53 & 26, respectively). Conclusion: Results from the current studies suggest that NBF-006, a very well tolerated monotherapy, can be used in combination with other drugs currently indicated for KRAS-mutant NSCLC to achieve more potent antitumor effects. Citation Format: Cima Cina, Akinori Sugiyama, Murali Kuracha, Nazia Abbasi, Dominic Medina, Hiroyuki Tanaka, Sonya Zabludoff. Enhanced growth inhibition in lung cancer cells through NBF-006 combination therapy with chemotherapy or KRAS inhibitors [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 C108.

P2.06-02 DEnosumab plus PD-1 Inhibitor for MAINtenance Therapy of Advanced KRAS-Mutant NSCLC - A Prospective, Single-Arm, Phase II Study (DEMAIN)

P2.06-02 DEnosumab plus PD-1 Inhibitor for MAINtenance Therapy of Advanced KRAS-Mutant NSCLC - A Prospective, Single-Arm, Phase II Study (DEMAIN)

1409P DEnosumab in combination with PD-1 checkpoint blockade for MAINtenance therapy of KRAS-mutant advanced NSCLC after first-line immunotherapy: A prospective, single-arm, phase II trial (DEMAIN)

1409P DEnosumab in combination with PD-1 checkpoint blockade for MAINtenance therapy of KRAS-mutant advanced NSCLC after first-line immunotherapy: A prospective, single-arm, phase II trial (DEMAIN)

Genome-Wide CRISPR Screens Identify Multiple Synthetic Lethal Targets That Enhance KRASG12C Inhibitor Efficacy.

Identification of synthetic lethal genes with KRASG12C using genome-wide CRISPR/Cas9 screening and credentialing of the ability of TEAD inhibition to enhance KRASG12C efficacy provides a roadmap for combination strategies. See related commentary by Johnson and Haigis, p. 4005.

Impact of KRASG12D subtype and concurrent pathogenic mutations on advanced non-small cell lung cancer outcomes

PurposeMutations in the Kirsten rat sarcoma viral (KRAS) oncogene constitute a significant driver of lung adenocarcinoma, present in 10–40% of patients, which exhibit heterogeneous clinical outcomes, mainly driven by concurrent genetic alterations. However, characterization of KRAS mutational subtypes and their impact on clinical outcomes in Latin America is limited.MethodsA cohort study was conducted at the National Cancer Institute (INCan) of Mexico. Individuals with advance-staged of adenocarcinoma and KRAS mutations, detected by next-generation sequencing, having undergone at least one line of therapy were included for analysis. Clinical and pathological characteristics were retrieved from institutional database from June 2014 to March 2023.ResultsKRAS was identified in fifty-four (15.6%) of 346 patients, among which 50 cases were included for analysis. KRASG12D (n = 16, 32%) and KRASG12C (n = 16, 32%) represented the most prevalent subtypes. KRASG12D mutations were associated with female (p = 0.018), never smokers (p = 0.108), and concurrences with EGFR (25.0% vs. 17.6%, p = 0.124) and CDKN2A (18.8% vs. 14.7%, p = 0.157). KRASG12D patients showed a better ORR (66.6% vs. 30.0%; OR 4.66, 95% CI 1.23–17.60, p = 0.023) and on multivariate analysis was significantly associated with better PFS (HR 0.36, 95% CI 0.16–0.80; p = 0.012) and OS (HR 0.24, 95% CI 0.08–0.70; p = 0.009).ConclusionsTo our knowledge, this study represents the first effort to comprehensively characterize the molecular heterogeneity of KRAS-mutant NSCLC in Latin American patients. Our data reinforce the current view that KRAS-mutated NSCLC is not a single oncogene-driven disease and emphasizes the prognostic impact of diverse molecular profiles in this genomically defined subset of NSCLC. Further validation is warranted in larger multicenter Latin American cohorts to confirm our findings.

Effect of trametinib and anti-PD-1 combo on tumor growth and survival of KRAS-mutant lung cancer by ID1 downregulation.

e14633 Background: Although anti-PD-1/PD-L1 antibodies represent a major breakthrough in NSCLC patients’ survival, this treatment efficacy is highly dependent on tumor PD-L1 expression. We reported the role of ID1 and the efficacy of a combined blockade of PD-1-ID1 in a KRAS mutant NSCLC mouse model (Baraibar et al; Cancers 2020). Trametinib, which is an oral MEK1/2 inhibitor, acts downstream of KRAS. Here we evaluate trametinib as an ID1 inhibitor able to enhance immunotherapy efficacy through PD-L1 overexpression. Methods: To explore whether MEK1/2 inhibition reduces ID1 expression in vitro and in vivo, experiments in NSCLC cells (human and murine) and in murine models were performed. RNAseq analysis was conducted to elucidate the pathways implicated in ID1 inhibition. Trametinib resistant (TR) cells were generated to analyze the effect of ID1 in the acquired resistance to treatment. Apoptosis was measured by flow cytometry. PD-L1 expression was evaluated by flow cytometry in control, ID1 silenced, ID1-overexpressing and TR cell lines. Treatment of trametinib combined with anti-PD1 was performed in KRAS-mutant LUAD models. Results: In vitro experiments in NSCLC cells showed ID1 inhibition at protein level after MEK1/2 blockade. However, we observe an increase in ID1 mRNA levels following treatment. In vivo experiments performed in C57BL6J and in ID1-deficient mice showed no significant differences in tumor growth between ID1 knock-out and ID1 wild-type mice treated with trametinib. IHC analysis of those tumor samples showed reduced ID1 levels (LLC p<0.001; CMT-167 p<0.0001). RNAseq analysis revealed an enrichment of ubiquitin-proteasome pathway after trametinib exposure. Blockade of proteasome activity with a specific inhibitor, restored ID1 levels. TR cells did not show MEKi induced ID1 inhibition, moreover, ID1 blockade rescued the sensitivity to trametinib in human and murine NSCLC TR cells (p<0.001). Flow cytometry analysis showed increased PD-L1 expression (p<0.001) in human and murine NSCLC cell lines after trametinib administration. In contrast, ID1-overexpressing cells and TR cells did not show PD-L1 upregulation after MEK inhibition. In vivo experiments confirmed the therapeutic efficacy of trametinib and anti-PD-1 combo, reducing tumor growth (p<0.05) and increasing mice survival (p<0.05), compared with trametinib monotherapy or immunotherapy alone. Conclusions: Pharmacological inhibition of MEK1/2 decreased ID1 expression in vitro and in vivo, replicating the effect of a specific shRNA against ID1, through proteasome activation. PD-L1 upregulation induced by ID1 blockade after trametinib treatment sensitized KRAS-mutant NSCLC cells to PD-1/PD-L1 immunotherapy, blocking tumor growth and improving overall survival.

Abstract 3852: IK-930, a paralog-selective novel TEAD-inhibitor, effectively attenuates drug-tolerant persister cell proliferation

Abstract The Hippo pathway is commonly mutated or altered in human cancers. In addition to the primary genetic driving mutations, the downstream effectors of the Hippo pathway comprising the transcriptional coactivators YAP1 and TAZ and the TEAD transcription factors can be activated upon prolonged inhibition of other oncogenic pathways such as EGFR and MAPK. We showed that combining the novel, paralog selective TEAD inhibitor, IK-930, with osimertinib or trametinib in EGFR or KRAS mutated tumors, led to enhanced apoptosis in vitro and beneficial antitumor activity in vivo. Experimental models demonstrated that upon inhibition of EGFR with osimertinib, a subpopulation of drug tolerant cells defined as ‘persisters’ can survive treatment allowing for the accumulation of additional genetic and epigenetic alterations. These alterations in the persister cells can give rise to resistant tumors and cancer relapse. Previous studies have implicated YAP/TEAD signaling in the emergence and survival of the persister cells. To investigate the role of YAP/TEAD signaling in persister cell emergence, EGFR and KRAS mutant NSCLC cell lines were engineered to express a TEAD luciferase reporter. Treatment with EGFR or MEK inhibitors, at concentrations that do not elicit significant cell death, induced TEAD-mediated transcription after several days of treatment, indicative of an adaptive response to chronic target inhibition. Concurrent treatment with the TEAD inhibitor, IK-930, abolished TEAD-mediated transcription. Using time lapse microscopy, the cell cycle and proliferation of EGFR mutant cultured cells, engineered to express a fluorescence-based cell-cycle indicator (FUCCI), were quantified when treated with osimertinib alone or combined with IK-930. Treatment with osimertinib led to a rapid induction of cell death. However, after several days, a drug tolerant population emerged and reentered the cell cycle even with chronic osimertinib treatment. Interestingly, the emergence of these persister cells coincided with maximum TEAD activity. Concurrent addition of IK-930, as well as addition of IK-930 after the emergence of the osimertinib-tolerant persister cells, attenuated cell proliferation and expansion, demonstrating the potential for IK-930 to prevent resistance to EGFR inhibitors and even reverse the effect when given after resistance has already emerged. Current efforts are focused on the characterization of the persister population and on evaluating the role of YAP/TEAD signaling in resistance to other targeted therapies. Citation Format: Daniel Hidalgo, Marta Sanchez-Martin, Mihir Rajurkar, George Punkosdy, Jeffrey Ecsedy, Lan Xu. IK-930, a paralog-selective novel TEAD-inhibitor, effectively attenuates drug-tolerant persister cell proliferation. [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 3852.

Histone Deacetylase 6 Inhibition Exploits Selective Metabolic Vulnerabilities in LKB1 Mutant, KRAS Driven NSCLC

IntroductionIn KRAS-mutant NSCLC, co-occurring alterations in LKB1 confer a negative prognosis compared with other mutations such as TP53. LKB1 is a tumor suppressor that coordinates several signaling pathways in response to energetic stress. Our recent work on pharmacologic and genetic inhibition of histone deacetylase 6 (HDAC6) revealed the impaired activity of numerous enzymes involved in glycolysis. On the basis of these previous findings, we explored the therapeutic window for HDAC6 inhibition in metabolically-active KRAS-mutant lung tumors. MethodsUsing cell lines derived from mouse autochthonous tumors bearing the KRAS/LKB1 (KL) and KRAS/TP53 mutant genotypes to control for confounding germline and somatic mutations in human models, we characterize the metabolic phenotypes at baseline and in response to HDAC6 inhibition. The impact of HDAC6 inhibition was measured on cancer cell growth in vitro and on tumor growth in vivo. ResultsSurprisingly, KL-mutant cells revealed reduced levels of redox-sensitive cofactors at baseline. This is associated with increased sensitivity to pharmacologic HDAC6 inhibition with ACY-1215 and blunted ability to increase compensatory metabolism and buffer oxidative stress. Seeking synergistic metabolic combination treatments, we found enhanced cell killing and antitumor efficacy with glutaminase inhibition in KL lung cancer models in vitro and in vivo. ConclusionsExploring the differential metabolism of KL and KRAS/TP53-mutant NSCLC, we identified decreased metabolic reserve in KL-mutant tumors. HDAC6 inhibition exploited a therapeutic window in KL NSCLC on the basis of a diminished ability to compensate for impaired glycolysis, nominating a novel strategy for the treatment of KRAS-mutant NSCLC with co-occurring LKB1 mutations.

Targeting KRASp.G12C Mutation in Advanced Non-Small Cell Lung Cancer: a New Era Has Begun.

KRASp.G12C mutation occurs in 12% of newly diagnosed advanced NSCLC and has recently emerged as a positive predictive biomarker for the selection of advanced NSCLC patients who may respond to novel KRASp.G12C inhibitors. The recent discovery of a new binding pocket under the effector region of KRAS G12C oncoprotein has made direct pharmacological inhibition of the KRASp.G12 mutation possible, leading to the clinical development of a new series of direct selective inhibitors, with a potential major impact on patients' survival and quality of life. Promising efficacy and tolerability data emerging from the early phase CodeBreak trial have already supported the regulatory approval of sotorasib as first in class targeted treatment for the second-line treatment of KRASp.G12C-positive NSCLC population, following immunotherapy-based first-line therapies, while the randomized phase III CodeBreak 200 clinical study has recently confirmed a significant superiority of sotorasib over docetaxel in terms of progression-free survival and quality of life. However, KRAS mutant NSCLC is a high heterogeneous disease characterized by a high rate of co-mutations, most frequently involving P53, STK11, and KEAP1 genes, which significantly modulate the composition of the tumor microenvironment and consequently affect clinical responses to both immunotherapy and targeted inhibitors now available in clinical practice. Both pre-clinical and clinical translational series have recently revealed a wide spectrum of resistance mechanisms occurring under selective KRASG12C inhibitors, including both on-target and off-target molecular alterations as well as morphological switching, negatively affecting the antitumor activity of these drugs when used as single agent therapies. The understanding of such biological background along with the emergence of pre-clinical data provided a strong rational to investigate different combination strategies, including the inhibition of SHP2, SOS1, and KRAS G12C downstream effectors, as well as the addition of immunotherapy and/or chemotherapy to targeted therapy. The preliminary results of these trials have recently suggested a promising activity of SHP2 inhibitors in the front-line setting, while toxicity issues limited the concurrent administration of immune-checkpoint inhibitors and sotorasib. The identification of predictive genomic/immunological biomarkers will be crucial to understand how to optimally sequencing/combining different drugs and ultimately personalize treatment strategies under clinical investigation, to definitively increase the survival outcomes of KRASp.G12C mutant advanced NSCLC patients.