Targeting KRASG12C in Non-Small-Cell Lung Cancer: Current Standards and Developments

Among the most common molecular alterations detected in non-small-cell lung cancer (NSCLC) are mutations in Kristen Rat Sarcoma viral oncogene homolog (KRAS). KRAS mutant NSCLC is a heterogenous group of diseases, different from other oncogene-driven tumors in terms of biology and response to therapies. Despite efforts to develop drugs aimed at inhibiting KRAS or its signaling pathways, KRAS had remained undruggable for decades. The discovery of a small pocket in the binding switch II region of KRASG12C has revolutionized the treatment of KRASG12C-mutated NSCLC patients. Sotorasib and adagrasib, direct KRASG12C inhibitors, have been approved by the US Food and Drug Administration (FDA) and other regulatory agencies for patients with previously treated KRASG12C-mutated NSCLC, and these advances have become practice changing. However, first-line treatment in KRASG12C-mutated NSCLC does not differ from NSCLC without actionable driver genomic alterations. Treatment with KRASG12C inhibitors is not curative and patients develop progressive disease, so understanding associated mechanisms of drug resistance is key. New KRASG12C inhibitors and several combination therapy strategies, including with immune checkpoint inhibitors, are being studied in clinical trials. The aim of this review is to explore the clinical impact of KRAS, and outline different treatment approaches, focusing on the novel treatment of KRASG12C-mutated NSCLC.

Emerging Therapies in Kirsten Rat Sarcoma Virus (+) Non-Small-Cell Lung Cancer

Kirsten rat sarcoma virus (KRAS) is the most frequently found oncogene in human cancers, including non-small-cell lung cancer (NSCLC). For many years, KRAS was considered "undruggable" due to its structure and difficult targeting. However, the discovery of the switch II region in the KRAS-G12C-mutated protein has changed the therapeutic landscape with the design and development of novel direct KRAS-G12C inhibitors. Sotorasib and adagrasib are FDA-approved targeted agents for pre-treated patients with KRAS-G12C-mutated NSCLC. Despite promising results, the efficacy of these novel inhibitors is limited by mechanisms of resistance. Ongoing studies are evaluating combination strategies for overcoming resistance. In this review, we summarize the biology of the KRAS protein and the characteristics of KRAS mutations. We then present current and emerging therapeutic approaches for targeting KRAS mutation subtypes intending to provide individualized treatment for lung cancer harboring this challenging driver mutation.

Efficacy of immune checkpoint inhibitors in advanced non-small cell lung cancer patients with KRAS mutations: A network meta-analysis

OBJECTIVE

Previous studies have shown that immune checkpoint inhibitors can improve the survival of patients with advanced non-small cell lung cancer with KRAS mutations; however, there is a lack of comparisons between treatment regimens associated with immune checkpoint inhibitors, and our study aims to compare several treatment parties to find a more effective treatment regimen.

METHOD

A comprehensive literature search was conducted across multiple databases, namely PubMed, Web of Science, Embase, and Cochrane Library, to identify relevant studies. The screened studies were thoroughly examined, and data were collected to establish a Bayesian framework. The study focused on two primary endpoints: overall survival (OS) and progression-free survival (PFS). Data analysis and graphical plotting using R software and Revman (version 5.3). It is worth mentioning that the study protocol was registered with the International Prospective Registry for Systematic Reviews, ensuring transparency and adherence to predetermined protocols (CRD42022379595).

RESULT

In total, our analysis included six RCTs involving 469 patients with KRAS mutations. Among these patients, 224 received chemotherapy, while 245 were treated with immune checkpoint inhibitors. Meta-analysis results showed that the addition of ICIs could significantly improve OS and PFS (0.69, 95% CI 0.55, 0.86; 0.57, 95% CI 0.42, 0.77). The results of the network meta-analysis showed that Pembrolizumab could improve OS (HR 0.42, 95% CI 0.22-0.80) and Pembrolizumab emerged as the most effective treatment option for enhancing OS in patients (SUCRA 65.03%). Additionally, pembrolizumab in combination with chemotherapy showed improvement in PFS (HR 0.47, 95% CI 0.29-0.76).

CONCLUSION

Our analysis found that among advanced NSCLC patients with KRAS gene mutations, first-line treatment with pembrolizumab alone demonstrated greater efficacy. Similarly, second-line treatment with nivolumab alone was found to be more effective in this patient population. However, the sample size of this study was limited, Therefore, additional clinical data is necessary to validate this finding in subsequent research.

Outcomes in patients treated with frontline immune checkpoint inhibition (ICI) for advanced NSCLC with KRAS mutations and STK11/KEAP1 comutations across PD-L1 levels

INTRODUCTION

In patients with advanced NSCLC (aNSCLC), the impact of KRAS mutations (m) and comutations with STK11 and KEAP1 on outcomes across different PD-L1 levels remains incompletely understood. We aimed to investigate the frequency of KRAS mutations and comutations across PD-L1 levels, and the association between these mutations and survival, stratified by PD-L1 expression.

METHODS

We conducted a nationwide cohort study of patients diagnosed with aNSCLC between 2016 and 2021 treated with frontline (chemo)immunotherapy, who underwent molecular genotyping including KRAS, STK11, and KEAP1. Real-world overall survival (OS) and progression-free survival (rwPFS) were estimated using Kaplan-Meier methodology. Cox multivariable regressions were used to evaluate the association between KRASm and survival across different PD-L1 strata, and to assess whether the association between KRASm and survival differed by PD-L1 level. Finally, within subgroups defined by PD-L1 expression, we used interaction terms to assess whether co-mutations with STK11 and KEAP1 moderated the association between KRAS mutation and survival.

RESULTS

Of our 2593-patient cohort, 982 (37.9 %) were KRASm and 1611 (62.1 %) KRASwt. KRASm were enriched in the PD-L1 ≥50 % cohort (334/743, 45 %), but within patients with KRASm, co-mutations with STK11 and KEAP1 were enriched in the PD-L1 0 % cohort. KRASm was associated with significantly worse OS in the PD-L1 0 % cohort compared to the PD-L1 ≥50 % cohort (P for interaction = 0.008). On adjusted analyses stratified by PD-L1, KRASm was associated with worse survival only in the PD-L1 0 % group (OS HR 1.46, p = 0.001). KEAP1 and STK11 comutations were most strongly associated with worse OS in the PD-L1 0 % subgroup; patients with triple KRASm/KEAPm/STK11m PD-L1 0 % NSCLC experienced the worst outcomes.

CONCLUSIONS

KRASm are associated with worse overall survival in PD-L1 negative NSCLC; however, this association is largely driven by comutations with STK11 and KEAP1, which are enriched in PD-L1 negative tumors.

Clinical and Genomic Characterization of Long-Term Responders Receiving Immune Checkpoint Blockade for Metastatic Non-Small-Cell Lung Cancer

OBJECTIVES

Understand from a real-world cohort the unique clinical and genomic determinants of a durable response to immune checkpoint inhibitors (ICIs).

MATERIALS AND METHODS

This is a retrospective study of patients with NSCLC who received any ICI-based regimen as first or second line therapy. Long-term responders (LTR) achieved an overall survival (OS) ≥ 3 years from time of treatment start, while nonresponders (NR) were patients who had an OS of 6 to 12 months from time of treatment start. Clinical and demographic covariables were collected from electronic medical records. Fisher's exact test and Mann-Whitney test were used to analyze the association of a long-term response to ICI in relation to clinical and genomic variables. All P-values were considered significant at P-value < .05.

RESULTS

A total of 72 patients were included in this study (LTR n = 37, NR n = 35). There were no significant differences in age, sex, race, and BMI between groups. The presence of liver metastases at the time of ICI initiation and PD-L1 status were not associated with LTR to ICIs. Patients in the LTR were more likely to experience irAEs at 3-,6- and 12-months. KRAS mutant tumors were numerically more common in the LTR group (n = 13 vs. 8).

CONCLUSION

We observe no strong clinical and biomarkers of a prolonged response to ICIs. Additional large prospective cohort studies are needed to investigate the genomic footprint of long-term responders.

Response to first-line pembrolizumab in metastatic KRAS-mutated non-small-cell lung cancer

Aims: This retrospective study aims to identify a possible predictive role of KRAS mutations in non-small-cell lung cancer in response to first-line pembrolizumab, either as monotherapy or combined with chemotherapy. Methods: Patients received pembrolizumab alone (n = 213) or associated with chemotherapy (n = 81). Results: A mutation in the KRAS gene was detected in 27% of patients. In patients on pembrolizumab alone, median progression-free survival in KRAS-mutated cases was longer than in wild-type cases (11.3 vs 4.4 months; p = 0.019), whereas median overall survival did not reach statistical significance (22.1 vs 12.5 months; p = 0.119). Patients receiving chemo-immunotherapy with KRAS-positive tumors had a similar progression-free survival (9.7 vs 7.3 months; p = 0.435); overall survival data were immature. Conclusion: This study suggests a correlation between KRAS status and response to pembrolizumab.

Efficacy of immunotherapy in patients with oncogene-driven non-small-cell lung cancer: a systematic review and meta-analysis

Background

Immunotherapy is an emerging antitumor therapy that can improve the survival of patients with advanced non-small-cell lung cancer (NSCLC). However, only about 20% of NSCLC patients can benefit from this treatment. At present, whether patients with driving gene-positive NSCLC can benefit from immunotherapy is one of the hot issues. Therefore, we conducted a meta-analysis to evaluate the efficacy of immunotherapy in patients with oncogene-driven NSCLC and concluded the efficacy of altered subtypes.

Methods

A literature search was performed using PubMed, Web of Science, and Cochrane databases. The primary endpoints included the objective response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS) in patients with oncogene-driven NSCLC.

Results

In all, 86 studies involving 4524 patients with oncogene-driven NSCLC were included in this meta-analysis. The pooled ORRs in clinical trials treated with monoimmunotherapy of EGFR, ALK, and KRAS alteration were 6%, 0%, and 23%, respectively. In retrospective studies, the pooled ORRs of EGFR, ALK, KRAS, BRAF, MET, HER2, RET, and ROS1 alteration were 8%, 3%, 28%, 24%, 23%, 14%, 7%, and 8%, respectively. Among them, the pooled ORRs of KRAS non-G12C mutation, KRAS G12C mutation, BRAF V600E mutation, BRAF non-V600E mutation, MET-exon 14 skipping, and MET-amplification were 33% 40%, 20%, 34%, 17%, and 60%, respectively. In addition, the pooled mPFS rates of EGFR, KRAS, MET, HER2, and RET alteration were 2.77, 3.24, 2.48, 2.31, and 2.68 months, while the pooled mOS rates of EGFR and KRAS alteration were 9.98 and 12.29 months, respectively. In prospective data concerning EGFR mutation, the pooled ORR and mPFS treated with chemo-immunotherapy (IC) reached 38% and 6.20 months, while 58% and 8.48 months with chemo-immunotherapy plus anti-angiogenesis therapy (ICA). Moreover, the pooled mPFS and mOS of monoimmunotherapy was 2.33 months and 12.43 months.

Conclusions

EGFR-, ALK-, HER2-, RET-, and ROS1-altered NSCLC patients have poor reactivity to monoimmunotherapy but the efficacy of immune-based combined therapy is significantly improved. KRAS G12C mutation, BRAF non-V600E mutation, and MET amplification have better responses to immunotherapy, and more prospective studies are needed for further research.

Is Immunotherapy Beneficial in Patients with Oncogene-Addicted Non-Small Cell Lung Cancers? A Narrative Review

Over the past 20 years, there has been a paradigm shift in the care of patients with non-small cell lung cancer (NSCLC), who now have a range of systemic treatment options including targeted therapy, chemotherapy, immunotherapy (ICI), and antibody-drug conjugates (ADCs). A proportion of these cancers have single identifiable alterations in oncogenes that drive their proliferation and cancer progression, known as "oncogene-addiction". These "driver alterations" are identified in approximately two thirds of patients with lung adenocarcinomas, via next generation sequencing or other orthogonal tests. It was noted in the early clinical development of ICIs that patients with oncogene-addicted NSCLC may have differential responses to ICI. The toxicity signal for patients with oncogene-addicted NSCLC when treated with ICIs also seemed to differ depending on the alteration present and the specific targeted agent used. Developing a greater understanding of the underlying reasons for these clinical observations has become an important area of research in NSCLC. In this review, we analyze the efficacy and safety of ICI according to specific mutations, and consider possible future directions to mitigate safety concerns and improve the outcomes for patients with oncogene-addicted NSCLC.

Prognostic Implication of KRAS G12C Mutation in a Real-World KRAS-Mutated Stage IV NSCLC Cohort Treated With Immunotherapy in The Netherlands

Introduction

With the approval of G12C inhibitors as the second line of treatment for KRAS G12C-mutated NSCLC, and the expanding research regarding targeting KRAS, it is key to understand the prognostic implication of KRAS G12C in the current first line of treatment. We compared overall survival (OS) of patients with stage IV KRAS G12C-mutated NSCLC to those with a KRAS non-G12C mutation in a first-line setting of (chemo)immunotherapy.

Methods

This nationwide population-based study used real-world data from The Netherlands Cancer Registry. We selected patients with stage IV KRAS-mutated lung adenocarcinoma diagnosed in 2019 to 2020 who received first-line (chemo-)immunotherapy. Primary outcome was OS.

Results

From 28,120 registered patients with lung cancer, 1185 were selected with a KRAS mutation, of which 494 had a KRAS G12C mutation. Median OS was 15.5 months (95% confidence interval [CI]: 13.6-18.4) for KRAS G12C versus 14.0 months (95% CI:11.2-15.7) for KRAS non-G12C (p = 0.67). In multivariable analysis, KRAS subtype was not associated with OS (hazard ratio = 0.95, 95% CI: 0.82-1.10). For the subgroup with programmed death-ligand 1 at 0% to 49% who received chemoimmunotherapy, median OS was 13.3 months (95% CI: 10.5-15.2) for G12C and 9.8 months (95% CI: 8.6-11.3) for non-G12C (p = 0.48). For the subgroup with programmed death-ligand 1 more than or equal to 50% who received monoimmunotherapy, the median OS was 22.0 months (95% CI: 18.4-27.3) for G12C and 18.9 months (95% CI: 14.9-25.2) for non-G12C (p = 0.36).

Conclusions

There was no influence of KRAS subtype (G12C versus non-G12C) on OS in patients with KRAS-mutated stage IV NSCLC treated with first-line (chemo)immunotherapy.

Canadian Consensus Recommendations on the Management of KRAS G12C-Mutated NSCLC

Activating mutations in Kirsten rat sarcoma viral oncogene homologue (KRAS), in particular, a point mutation leading to a glycine-to-cysteine substitution at codon 12 (G12C), are among the most frequent genomic alterations in non-small cell lung cancer (NSCLC). Several agents targeting KRAS G12C have recently entered clinical development. Sotorasib, a first-in-class specific small molecule that irreversibly inhibits KRAS G12C, has since obtained Health Canada approval. The emergence of novel KRAS-targeted therapies warrants the development of evidence-based consensus recommendations to help clinicians better understand and contextualize the available data. A Canadian expert panel was convened to define the key clinical questions, review recent evidence, and discuss and agree on recommendations for the treatment of advanced KRAS G12C-mutated NSCLC. The panel agreed that testing for KRAS G12C should be performed as part of a comprehensive panel that includes current standard-of-care biomarkers. Sotorasib, the only approved KRAS G12C inhibitor in Canada, is recommended for patients with advanced KRAS G12C-mutated NSCLC who progressed on guideline-recommended first-line standard of care for advanced NSCLC without driver alterations (immune-checkpoint inhibitor(s) [ICIs] +/- chemotherapy). Sotorasib could also be offered as second-line therapy to patients who progressed on ICI monotherapy that are not candidates for a platinum doublet and those that received first-line chemotherapy with a contraindication to ICIs. Preliminary data indicate the activity of KRAS G12C inhibitors in brain metastases; however, the evidence is insufficient to make specific recommendations. Regular liver function monitoring is recommended when patients are prescribed KRAS G12C inhibitors due to risk of hepatotoxicity.

A Critical Review of the Prognostic and Predictive Implications of KRAS and STK11 Mutations and Co-Mutations in Metastatic Non-Small Lung Cancer

The Kirsten rat sarcoma viral oncogene homolog (KRAS) and serine/threonine kinase 11 (STK11) co-mutations are associated with the diverse phenotypic and heterogeneous oncogenic subtypes in non-small cell lung cancer (NSCLC). Due to extensive mixed evidence, there needs to be a review of the recent KRAS and STK11 mutation literature to better understand the potential clinical applications of these genomic biomarkers in the current treatment landscape. This critical review highlights the clinical studies that have elucidated the potential prognostic and predictive implications of KRAS mutations, STK11 mutations, or KRAS/STK11 co-mutations when treating metastatic NSCLC across various types of treatments (e.g., immune checkpoint inhibitors [ICIs]). Overall, KRAS mutations are associated with poor prognoses and have been determined to be a valid but weak prognostic biomarker among patients diagnosed with NSCLC. KRAS mutations in NSCLC have shown mixed results as a predictive clinical biomarker for immune checkpoint inhibitor treatment. Overall, the studies in this review demonstrate that STK11 mutations are prognostic and show mixed results as predictive biomarkers for ICI therapy. However, KRAS/STK11 co-mutations may predict primary resistance to ICI. Prospective KRAS/STK11-biomarker-driven randomized trials are needed to assess the predictive effect of various treatments on the outcomes for patients with metastatic NSCLC, as the majority of the published KRAS analyses are retrospective and hypothesis-generating in nature.

Overall survival in patients with advanced non-small cell lung cancer with KRAS G12C mutation with or without STK11 and/or KEAP1 mutations in a real-world setting

BACKGROUND

KRAS mutations occur frequently in advanced non-small cell lung cancer (aNSCLC); the G12C mutation is the most prevalent. Alterations in STK11 or KEAP1 commonly co-occur with KRAS mutations in aNSCLC. Using real-world data, we assessed the effect of KRAS G12C mutation with or without STK11 and/or KEAP1 mutations on overall survival (OS) in patients with aNSCLC receiving cancer immunotherapy (CIT), chemotherapy, or both in first line (1L) and second line (2L).

METHODS

Patients diagnosed with aNSCLC between January 2011 and March 2020 in a clinico-genomic database were included. Cox proportional hazards models adjusted for left truncation, baseline demographics and clinical characteristics were used to analyze the effect of STK11 and/or KEAP1 co-mutational status on OS in patients with KRAS wild-type (WT) or G12C mutation.

RESULTS

Of 2715 patients with aNSCLC without other actionable driver mutations, 1344 (49.5%) had KRAS WT cancer, and 454 (16.7%) had KRAS G12C-positive cancer. At 1L treatment start, significantly more patients with KRAS G12C-positive cancer were female, smokers, and had non-squamous histology, a higher prevalence of metastasis and programmed death-ligand 1 positivity than those with KRAS WT cancer. Median OS was comparable between patients with KRAS G12C-positive and KRAS WT cancer when receiving chemotherapy or combination CIT and chemotherapy in the 1L or 2L. Median OS was numerically longer in patients with KRAS G12C vs KRAS WT cancer treated with 1L CIT (30.2 vs 10.6 months, respectively) or 2L CIT (11.3 vs 7.6 months, respectively). Co-mutation of STK11 and KEAP1 was associated with significantly shorter OS in patients receiving any type of 1L therapy, regardless of KRAS G12C mutational status.

CONCLUSIONS

This real-world study showed that patients with KRAS G12C-positive or KRAS WT cancer have similar OS in the 1L or 2L when treated with chemotherapy or combination CIT and chemotherapy. In contrast to aNSCLC patients with EGFR or ALK driver mutations, patients with KRAS G12C-positive cancer may benefit from CIT monotherapy. Co-mutation of STK11 and KEAP1 was associated with significantly shorter survival, independent of KRAS G12C mutational status, reflecting the poor prognosis and high unmet need in this patient population.

Efficacy of immunotherapy in KRAS-mutant advanced NSCLC: A real-world study in a Chinese population

Background

Immunotherapy has improved the clinical outcomes of patients with advanced non-small cell lung cancer (NSCLC). However, in patients with Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations, the superior efficacy of immunotherapy has not been elucidated and especially in real-world practice. Our study aimed to use real-world data to assess the efficacy of immunotherapy in KRAS-mutant NSCLC in a Chinese cohort.

Methods

In this retrospective cohort study, we extracted the clinical, molecular, and pathologic data from the electronic health records of patients with advanced KRAS-mutant NSCLC at Shandong Cancer Hospital between January 2018 and May 2022. Furthermore, we evaluated the progression-free survival (PFS) and overall survival (OS) of the included patients.

Results

Between January 2018 and November 2020, 793 patients were identified with stage IIIB-IV NSCLC and a total of 122 patients with KRAS mutations were included in the analysis. The majority of patients were diagnosed with stage IV (82.0%) adenocarcinoma (93.4%), along with a history of smoking (57.4%). Of these, 42% of patients received anti-PD-(L)1 with or without chemotherapy (Immunotherapy-based regimens), while 58.2% of patients received chemotherapy (Chemotherapy-based regimens). The median overall survival (mOS) in this cohort was 22.9 months (95% CI: 14.1-31.7), while the median-progression-free survival (mPFS) was 9.4 months (95% CI: 6.6-12.1). Patients receiving immunotherapy-based regimens displayed better mOS than those receiving chemotherapy-based regimens (45.2 vs. 11.3 months; P=1.81E-05), with no statistical difference observed in the mPFS (10.5 vs. 8.2 months; P=0.706). Patients receiving immunotherapy-based regimens either in the first line (P=0.00038, P=0.010, respectively) or second-line setting (P=0.010, P=0.026, respectively) showed benefits in both PFS and OS. Subgroup analysis indicated that in patients having KRAS G12C or non-KRAS G12C mutant types, immunotherapy showed benefits of better OS (P=0.0037, P=0.020, respectively) than chemotherapy. Moreover, in advanced NSCLCs patients with or without KRAS/TP53 co-mutation the immunotherapy-based regimen achieved longer OS and PFS than chemotherapy-based regimens.

Conclusions

In the Chinese population of patients with KRAS-mutant advanced NSCLC, immunotherapy-based regimens achieved longer OS than chemotherapy-based regimens, which was independent of first or second-line setting, as well as KRAS mutational subtypes.

Predictors of survival to immunotherapy and chemoimmunotherapy in non-small cell lung cancer: A meta-analysis

BACKGROUND

Many patients with non-small cell lung cancer (NSCLC) derive poor benefit from immunotherapy (IO). For some of them, adding chemotherapy (CT) can improve the outcomes, but the reliability of programmed death-ligand 1 (PD-L1) expression as the only biomarker to distinguish these patients is unsatisfactory. We sought to detect clinicopathological and molecular predictive factors of survival that might be added to PD-L1 expression in the selection of patients who should receive IO alone or chemoimmunotherapy (CIT).

METHODS

We conducted a systematic search of randomized controlled clinical trials investigating IO, alone or with CT, vs CT alone in treatment-naïve advanced NSCLC patients. Meta-analyses and meta-regression analyses were performed to investigate IO alone vs CT, CIT vs CT, and IO alone vs CIT.

RESULTS

A total of 14 367 patients with advanced NSCLC across 25 randomized controlled clinical trials were included. Squamous histology, male sex, current and former smoker status, PD-L1 expression of 50% or more, and high tumor mutational burden (TMB) correlated with improved survival with IO alone compared with CT. Conversely, female sex, no smoking history, negative PD-L1 expression, and low TMB correlated with unsatisfactory outcomes with IO alone vs CT but not with CIT vs CT. CIT improved survival vs IO alone in female patients, never smokers, those having a PD-L1 expression of 1% or more (but not with a PD-L1 of  ≥ 50%) or a low TMB and in patients with central nervous system metastasis.

CONCLUSIONS

These findings suggest some clinicopathological and molecular features that, added to PD-L1 expression, could help in the selection of the most appropriate first-line IO-based treatment for advanced NSCLC patients.

Emerging Biomarkers in Immune Oncology to Guide Lung Cancer Management

Over the last decade, the use of targeted therapies and immune therapies led to drastic changes in the management lung cancer and translated to improved survival outcomes. This growing arsenal of therapies available for the management of non-small cell lung cancer added more complexity to treatment decisions. The genomic profiling of tumors and the molecular characterization of the tumor microenvironment gradually became essential steps in exploring and identifying markers that can enhance patient selection to facilitate treatment personalization and narrow down therapy options. The advent of innovative diagnostic platforms, such as next-generation sequencing and plasma genotyping (also known as liquid biopsies), has aided in this quest. Currently, programmed cell death ligand 1 expression remains the most recognized and fully validated predictive biomarker of response to immune checkpoint inhibitors. Other markers such as tumor mutational burden, tumor infiltrating lymphocytes, driver mutations, and other molecular elements of the tumor microenvironment bear the potential to be predictive tools; however, the majority are still investigational. In this review, we describe the advances noted thus far on currently validated as well as novel emerging biomarkers that have the potential to guide the use of immunotherapy agents in the management of non-small cell lung cancer.

Efficacy of immunotherapy in oncogene-driven non-small-cell lung cancer

For advanced metastatic non-small-lung cancer, the landscape of actionable driver alterations is rapidly growing, with nine targetable oncogenes and seven approvals within the last 5 years. This accelerated drug development has expanded the reach of targeted therapies, and it may soon be that a majority of patients with lung adenocarcinoma will be eligible for a targeted therapy during their treatment course. With these emerging therapeutic options, it is important to understand the existing data on immune checkpoint inhibitors (ICIs), along with their efficacy and safety for each oncogene-driven lung cancer, to best guide the selection and sequencing of various therapeutic options. This article reviews the clinical data on ICIs for each of the driver oncogene defined lung cancer subtypes, including efficacy, both for ICI as monotherapy or in combination with chemotherapy or radiation; toxicities from ICI/targeted therapy in combination or in sequence; and potential strategies to enhance ICI efficacy in oncogene-driven non-small-cell lung cancers.

The Path to Personalized Treatment in KRAS-Mutant Non-Small Cell Lung Cancer: A Review of Targeted Therapies and Immunotherapy

Purpose of Review

To summarize the targeted therapies and immunotherapy of Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutant non-small cell lung cancer (NSCLC), and discuss the ongoing clinical trials.

Recent Findings

KRAS mutations occur in about 30% of patients with NSCLC and are the second most frequent genetic variation in lung cancer. It has been considered "undruggable" for 40 years until the discovery of a direct inhibitor of KRAS G12C. The promising direct KRAS G12C inhibitors such as sotorasib and MRTX849 have made a breakthrough with promising anti-tumor effects in patients with KRAS G12C-mutant advanced/metastatic NSCLC post one prior line of therapy. Following the success of immune checkpoint inhibitors (ICIs) in NSCLC, many patients harboring KRAS mutations can benefit from ICIs. However, due to disease heterogeneity, the prognosis of patients remains unsatisfactory, leaving room for personalized treatment options, such as new targeted therapies and other therapies.

Summary

In this review, we aim to dissect the strategies of clinical trials in these tumors, shifting from a few chemotherapy options to targeted and immunotherapy, in the context of molecular selection of KRAS-mutant NSCLC subtypes.

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

Purpose

For 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.

Methods

KRAS 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.

Results

Fifty 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).

Conclusion

For 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.

KRAS G12 isoforms exert influence over up-front treatments: A retrospective, multicenter, Italian analysis of the impact of first-line immune checkpoint inhibitors in an NSCLC real-life population

BACKGROUND

KRAS is commonly mutated in non-small cell lung cancer (NSCLC); however, the prognostic and predictive impact of each G12 substitution has not been fully elucidated. The approval of specific G12C inhibitors has modified the idea of KRAS "undruggability", and although the first-line standard consists of immune checkpoint inhibitors (ICIs) with or without chemotherapy, as suggested at ASCO 2022, the outcome in KRAS-mutated population is still controversial.

METHODS

We retrospectively described the clinical and pathological characteristics of a homogeneous G12 mutated cohort of 219 patients treated in four Italian oncologic units. We evaluated the outcome (PFS at 18 months and OS at 30 months) of those who underwent standard first-line treatment according to PD-L1 status, focusing on differences across single mutations.

RESULTS

In the study population, 47.9% of patients harbor the KRAS G12C mutation; 20.5%, G12V; 17.4%, G12D; and 8.2%, G12A. Smoking was a common behavior of patients harboring transversions and transition mutations. PD-L1 expression does not show particular distribution in the case series, although we recorded a prevalence of PD-L1 <1% in G12V (51.4%) compared to G12A (26.7%). ICIs alone was the clinician's choice in 32.7% of patients, and the chemo-immune combination in 17.3% of patients. We described the independent prognostic role of young age (p = 0.007), female gender (p = 0.016), and an ICI-based regimen (p = 0.034) regardless of mutations. Overall, our data confirm the worst prognostic value of G12V mutation apart from treatment choice unlike the other major mutations (C, D, and A) that showed a favorable trend in PFS.

CONCLUSIONS

KRAS G12 mutations are confirmed to have different characteristics, and the outcome is influenced by ICI first-line regimen. This study provides valuable information for further analysis in the future.

KRAS in NSCLC: State of the Art and Future Perspectives

In NSCLC, KRAS mutations occur in up to 30% of all cases, most frequently at codon 12 and 13. KRAS mutations have been linked to adenocarcinoma histology, positive smoking history, and Caucasian ethnicity, although differences have been described across KRAS mutational variants subtypes. KRAS mutations often concur with other molecular alterations, notably TP53, STK11, and KEAP1, which could play an important role in treatment efficacy and patient outcomes. For many years, KRAS mutations have been considered undruggable mainly due to a high toxicity profile and low specificity of compounds. Sotorasib and adagrasib are novel KRAS inhibitors that recently gained FDA approval for pre-treated KRAS mutant NSCLC patients, and other molecules such as GDC-6036 are currently being investigated with promising results. Despite their approval, the efficacy of these drugs is lower than expected and progression among responders has been reported. Mechanisms of acquired resistance to anti-KRAS molecules typically involves either on target secondary mutations (e.g., G12, G13, Q61H, R68S, H95, Y96C, V8L) or off-target alterations. Ongoing trials are currently evaluating strategies for implementing efficacy and overcoming acquired resistance to these compounds. Finally, the efficacy of immune-checkpoint inhibitors still needs to be completely assessed and responses to anti-PD-1/PD-L1 agents may strongly depend on concomitant mutations.

Therapeutic Outcomes and Clinical Features of Advanced Non-Small Cell Lung Cancer Carrying KRAS Mutations: A Multicenter Real-life Retrospective Study

INTRODUCTION

Targeting Kirsten Rat Sarcoma (KRAS) has been deemed impossible for long time, but new drugs have recently demonstrated promising results. Evidence on the outcome of KRAS-mutant advanced-NSCLC treated with new standard regimens are still scarce. Thus, we aimed at assessing the incidence and clinical impact of KRAS mutations in a real-life population of advanced-NSCLC, exploring the prognostic significance of distinct alterations.

MATERIALS AND METHODS

The present multicenter retrospective study, conducted by 5 Italian Centers from January 2018 to February 2020, involved 297 advanced KRAS mutant NSCLC. Complete clinico-pathological data were evaluated.

RESULTS

Out of 297 patients, 130 carried KRAS_G12C mutation, while 167 presented with mutations other than G12C. Within KRAS_non-G12C group, 73%, 16.8% and 8.9% harboured G12X, codon 13 and Q61H alterations, respectively. No significant differences in survival outcome and treatment response were documented according to KRAS_G12C versus non-G12C, nor KRAS_G12C versus G12X versus other mutations. On univariate analysis ECOG PS, number and sites of metastatic lesions and PD-L1 status significantly impacted on survival. A clear trend towards worse prognosis was apparent in chemotherapy-treated patients, while immunotherapy-based regimens were associated to prolonged survival. Investigating the outcome of PD-L1 ≥ 50% population, we did not detect any significant difference between KRAS_G12C and non-G12C subsets.

CONCLUSION

Here, we report on real-life data from a large retrospective cohort of advanced NSCLC harbouring KRAS alterations, with particular attention to G12C mutation. Our study offers useful clues on survival outcome, therapeutic response and clinico-pathological correlations in KRAS-mutant setting, especially in the upcoming era of KRAS G12C targeting therapy.

An evaluation of sotorasib for the treatment of patients with non-small cell lung cancer with KRAS G12C mutations

INTRODUCTION

Improving the clinical outcomes of patients with KRAS^G12C-mutated non-small cell lung cancer (NSCLC), the majority of whom are current or former smokers, has been a barrier to improving population-level outcomes in NSCLC. Novel, effective KRAS^G12C inhibitors are emerging and sotorasib is the first member of that class to achieve commercial availability.

AREAS COVERED

In this review, we survey the epidemiology of KRAS^G12C-mutated NSCLC, as well as sotorasib's chemistry, pharmacology, and clinical trial data.

EXPERT OPINION

While sotorasib's development has been unique and exciting, questions persist regarding its intracranial penetrance, optimal dose, and efficacy relative to standard-of-care therapy. Improvements in the clinical activity of KRAS inhibition will hinge on better understanding of resistance mechanisms, the development of broad-spectrum inhibitors with activity beyond G12C mutations, and combination therapy targeting multiple mediators of KRAS signaling and alternative pathways. From a regulatory perspective, sotorasib's development may, in time, prove to be an instructive example for early-phase clinical trialists and regulators focused on dose optimization.

RAS oncogenic activity predicts response to chemotherapy and outcome in lung adenocarcinoma

Activating mutations in KRAS occur in 32% of lung adenocarcinomas (LUAD). Despite leading to aggressive disease and resistance to therapy in preclinical studies, the KRAS mutation does not predict patient outcome or response to treatment, presumably due to additional events modulating RAS pathways. To obtain a broader measure of RAS pathway activation, we developed RAS84, a transcriptional signature optimised to capture RAS oncogenic activity in LUAD. We report evidence of RAS pathway oncogenic activation in 84% of LUAD, including 65% KRAS wild-type tumours, falling into four groups characterised by coincident alteration of STK11/LKB1, TP53 or CDKN2A, suggesting that the classifications developed when considering only KRAS mutant tumours have significance in a broader cohort of patients. Critically, high RAS activity patient groups show adverse clinical outcome and reduced response to chemotherapy. Patient stratification using oncogenic RAS transcriptional activity instead of genetic alterations could ultimately assist in clinical decision-making.

The Efficacy of Immune Checkpoint Inhibitors vs. Chemotherapy for KRAS-Mutant or EGFR-Mutant Non-Small-Cell Lung Cancers: A Meta-Analysis Based on Randomized Controlled Trials

Objective

To assess and compare the effectiveness of immune checkpoint inhibitors vs. chemotherapy for KRAS-mutant or EGFR-mutant non-small-cell lung cancers.

Methods

Until February 19, 2022, Cochrane Library, PubMed, Web of Science, and Embase were searched for relevant randomized controlled trials (RCTs) in NSCLC. Progression-free survival (PFS) and overall survival (OS) were used as outcome measures. The studies were conducted using the Cochrane methodology for meta-analyses, and all statistical analyses were made with Review Manager Software (RevMan version 5.4).

Results

Our meta-analysis included nine clinical trials including 5633 participants with NSCLC. Immune checkpoint drugs extended OS (hazard ratio (HR), 0.67; 95% confidence interval (CI), 0.60–0.76) and PFS (HR, 0.44; 95% CI, 0.35-0.56) in patients with EGFR wild-type compared to chemotherapy alone, whereas programmed cell death 1 ligand 1 (PD-L1)/programmed cell death-1 (PD-1) inhibitors with chemotherapy versus chemotherapy extended PFS in NSCLC patients with EGFR mutations (HR, 0.63; 95% CI, 0.42-0.94). Meanwhile, immune checkpoint inhibitors vs. chemotherapy improved the OS (HR, 0.65; 95% CI, 0.48–0.88) and PFS (HR, 0.49; 95% CI, 0.36–0.66) of NSCLC patients with KRAS mutation. NSCLCs with KRAS G12C mutation had a much better PFS with ICIs than with chemotherapy (HR, 0.38; 95% CI, 0.21–0.71).

Conclusion

This research revealed that individuals with EGFR wild-type NSCLC or KRAS mutation may benefit from PD-L1/PD-1 inhibitors and that PD-L1/PD-1 inhibitors in combination with chemotherapy seem to be more successful than chemotherapy alone in NSCLC patients with EGFR mutation.

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

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.

Evaluation of the Molecular Landscape in PD-L1 Positive Metastatic NSCLC: Data from Campania, Italy

Background: Immune-checkpoint inhibitors (ICIs) have increased and improved the treatment options for patients with non-oncogene-addicted advanced stage non-small cell lung cancer (NSCLC). However, the role of ICIs in oncogene-addicted advanced stage NSCLC patients is still debated. In this study, in an attempt to fill in the informational gap on the effect of ICIs on other driver mutations, we set out to provide a molecular landscape of clinically relevant oncogenic drivers in programmed death-ligand 1 (PD-L1) positive NSCLC patients. Methods: We retrospectively reviewed data on 167 advanced stage NSCLC PD-L1 positive patients (≥1%) who were referred to our clinic for molecular evaluation of five driver oncogenes, namely, EGFR, KRAS, BRAF, ALK and ROS1. Results: Interestingly, n = 93 (55.7%) patients showed at least one genomic alteration within the tested genes. Furthermore, analyzing a subset of patients with PD-L1 tumor proportion score (TPS) ≥ 50% and concomitant gene alterations (n = 8), we found that n = 3 (37.5%) of these patients feature clinical benefit with ICIs administration, despite the presence of a concomitant KRAS gene alteration. Conclusions: In this study, we provide a molecular landscape of clinically relevant biomarkers in NSCLC PD-L1 positive patients, along with data evidencing the clinical benefit of ICIs in patient NSCLC PD-L1 positive alterations.

Characteristics and Treatment Outcomes in Advanced-Stage Non-Small Cell Lung Cancer Patients with a KRAS G12C Mutation: A Real-World Study

About 15% of patients with non-small cell lung cancer (NSCLC) harbor the Kirsten rat sarcoma homolog G12C mutation (KRAS^G12C). Selective KRAS^G12C inhibitors offer new treatment opportunities, but little is known about the prevalence, characteristics, and outcomes of standard-of-care treatment (SOC) in this population. We retrospectively assessed the clinicopathological features of patients with KRAS^G12C-mutated advanced NSCLC and responses to SOC at two high-volume centers in Austria. Out of 2495 NSCLC patients tested, we identified 174 patients with advanced-stage disease carrying a KRAS^G12C mutation. Most patients were ≥65 years old (55%), heavy smokers (55%), and presented with comorbidities. The most frequent co-alteration was TP53 (18%). PD-L1 expression was high (TPS ≥ 50%) in 31%, very high (TPS ≥ 90%) in 11%, and negative in 31% of patients. A total of 138 patients (79%) received oncologic systemic treatment. The most common first-line therapy (1 L) was anti-PD-1/PD-L1 plus platinum-based chemotherapy. Median overall survival measured from 1 L treatment was 15.3 months (95% CI, 8.6–21.9), 9.4 (95% CI, 5.3–13.5) from 2 L treatment, and 8.4 (95% CI, 1.7–15.1) from 3 L treatment. The time-to-next-treatment was 8.4 (95% CI, 5.2–11.6) from 1 L and 6.1 (95% CI, 2.7–9.7) months from 2 L to 3 L. These poor outcomes underscore the need for the implementation of new treatment options and for specific molecular testing.

Impact of KRAS Mutation Subtypes and Co-Occurring Mutations on Response and Outcome in Advanced NSCLC Patients following First-Line Treatment

(1) Background: The purpose was to systematically assess the impact of KRAS subtypes and co-mutations on responses of first-line treatment and outcomes by genetic classification in advanced KRAS mutant NSCLC. (2) Methods: Molecular pathology was confirmed with NGS; Kaplan−Meier analysis and Cox multivariate model were used to analyze the efficacy of first-line treatment and prognosis in KRAS subgroups. (3) Results: Advanced KRAS mutant NSCLC was confirmed among 183 patients, who received first-line therapy. The most common KRAS subtype and co-mutation were G12C (29.5%) and TP53 (59.6%). ICIs/CHE group prolonged PFS to 16.9 m, vs. (CHE)4.6 m vs. (CHE/BEV)7.0 m (p < 0.0001); mOS (ICIs/CHE)37.1 m vs. (CHE)19.8 m vs. [CHE/BEV] 20.7 m (p = 0.024). PFS benefited to different degrees after first-line ICI-based treatment in each genetic classification. KRAS G12D even benefited from OS (p = 0.045). CHE/BEV prolonged mPFS of KRAS/STK11 co-mutation (p = 0.043), but decreased mPFS in G12A subtype (p = 0.026). Multivariate analysis indicated that heavy smoking history (≥20 pack-years) (HR = 0.45, p = 0.039) predicts optimistic prognosis; PS score 1 (HR = 3.604, p = 0.002) and KRAS/SMAD4 co-mutation (HR = 4.293, p = 0.027) remained as independent predictors of shorter OS. (4) Conclusions: First-line treatment with ICI benefited KRAS-mutant-NSCLC patients and resulted in non-negative predictive value for any genetic classification. Bevacizumab should be cautiously chosen for patients with KRAS G12A subtype but is recommended for KRAS/STK11 patients. KRAS/SMAD4 is a new co-mutation genotype that displayed independent risk prognostic factors in patients with advanced KRAS-mutant NSCLC.

Efficacy of first‐line immune checkpoint inhibitors in patients with advanced NSCLC with KRAS , MET , FGFR , RET , BRAF , and HER2 alterations

Background

In patients with non‐small cell lung cancer (NSCLC) harboring driver alterations, the efficacy of immune checkpoint inhibitors (ICIs) remains uncertain. Our study aimed to examine the first‐line ICI efficacy in patients with NSCLC harboring KRAS, MET, FGFR, RET, BRAF, and HER2 alterations in a real‐world setting.

Methods

This single‐center, retrospective cohort study included patients with advanced NSCLC harboring KRAS, MET, FGFR, RET, BRAF, HER2 alterations or driver‐negative, and were treated with first‐line ICI therapy. Best overall response, progression‐free survival (PFS), and overall survival (OS) were evaluated.

Results

Seventy‐eight patients with NSCLC were included (median age, 72 years): 67% were men, 15% were never‐smokers, and 83% had adenocarcinoma. The driver alterations involved KRAS (n = 21), MET (n = 6), FGFR (n = 3), RET (n = 2), BRAF (n = 2), HER2 (n = 1), and driver‐negative (n = 43). The partial responses for KRAS, MET, FGFR, RET, BRAF, HER2, and driver‐negative were 57%, 50%, 100%, 50%, 100%, 0%, and 47%, respectively. The median PFS (months) was 16.2 (95% confidence interval [CI]: 6.3– not reached [NR]) for KRAS, 2.8 (95% CI: 2.7–NR) for MET, 11.7 (95% CI: 5.9–NR) for other alterations (FGFR, RET, BRAF, and HER2), and 10.0 (95% CI: 3.7–14.3) for driver‐negative, respectively. The median OS (months) was 31.3 (95% CI: 9.0–NR) for KRAS, not reached for MET, 23.5 (95% CI: 18.3–NR) for other alterations, and 21.1 (95% CI: 15.2–NR) for driver‐negative, respectively.

Conclusions

The benefit of the first‐line ICI was similar in advanced NSCLC regardless of the driver alterations, except for MET alterations.

Limited role of KRAS mutation in guiding immunotherapy in advanced non-small-cell lung cancer

The success of sotorasib (AMG-510) and adagrasib (MRTX-849) has resolved the problem of non-availability of drugs for patients with KRAS_G12C-mutated non-small-cell lung cancer. However, more research is required before these drugs can be introduced as a first-line treatment for those patients, and there are no available drugs for other non-G12C-mutated patients so far; therefore, immunotherapy remains the optimal first-line treatment in this situation. The role of KRAS in affecting the response to immunotherapy in non-small-cell lung cancer has not been fully elucidated. The purpose of this review was to summarize the impact of KRAS mutations, a highly heterogeneous group, on immunotherapy to provide clinicians and researchers with relevant information that can help guide decision-making.

KRAS Mutations Impact Clinical Outcome in Metastatic Non-Small Cell Lung Cancer

There is an urgent need to identify new predictive biomarkers for treatment response to both platinum doublet chemotherapy (PT) and immune checkpoint blockade (ICB). Here, we evaluated whether treatment outcome could be affected by KRAS mutational status in patients with metastatic (Stage IV) non-small cell lung cancer (NSCLC). All consecutive patients molecularly assessed and diagnosed between 2016−2018 with Stage IV NSCLC in the region of West Sweden were included in this multi-center retrospective study. The primary study outcome was overall survival (OS). Out of 580 Stage IV NSCLC patients, 35.5% harbored an activating mutation in the KRAS gene (KRASMUT). Compared to KRAS wild-type (KRASWT), KRASMUT was a negative factor for OS (p = 0.014). On multivariate analysis, KRASMUT persisted as a negative factor for OS (HR 1.478, 95% CI 1.207−1.709, p < 0.001). When treated with first-line platinum doublet (n = 195), KRASMUT was a negative factor for survival (p = 0.018), with median OS of 9 months vs. KRASWT at 11 months. On multivariate analysis, KRASMUT persisted as a negative factor for OS (HR 1.564, 95% CI 1.124−2.177, p = 0.008). KRASMUT patients with high PD-L1 expression (PD-L1high) had better OS than PD-L1highKRASWT patients (p = 0.036). In response to first-line ICB, KRASMUT patients had a significantly (p = 0.006) better outcome than KRASWT patients, with a median OS of 23 vs. 6 months. On multivariable Cox analysis, KRASMUT status was an independent prognostic factor for better OS (HR 0.349, 95% CI 0.148−0.822, p = 0.016). kRAS mutations are associated with better response to treatment with immune checkpoint blockade and worse response to platinum doublet chemotherapy as well as shorter general OS in Stage IV NSCLC.

Targeting KRAS Mutant in Non-Small Cell Lung Cancer: Novel Insights Into Therapeutic Strategies

Although KRAS-activating mutations represent the most common oncogenic driver in non-small cell lung cancer (NSCLC), various attempts to inhibit KRAS failed in the past decade. KRAS mutations are associated with a poor prognosis and a poor response to standard therapeutic regimen. The recent development of new therapeutic agents (i.e., adagrasib, sotorasib) that target specifically KRAS G12C in its GDP-bound state has evidenced an unprecedented success in the treatment of this subgroup of patients. Despite providing pre-clinical and clinical efficacy, several mechanisms of acquired resistance to KRAS G12C inhibitors have been reported. In this setting, combined therapeutic strategies including inhibition of either SHP2, SOS1 or downstream effectors of KRAS G12C seem particularly interesting to overcome acquired resistance. In this review, we will discuss the novel therapeutic strategies targeting KRAS G12C and promising approaches of combined therapy to overcome acquired resistance to KRAS G12C inhibitors.

Targeting KRAS G12C mutation in lung adenocarcinoma

Lung cancer continues to be a major cause of cancer related death globally. Therapies targeting driver mutations have significantly extended the survival of patients whose lung cancer cells harbor these mutations. Patients with KRAS mutations, however, lacked specific targeted therapy until the recent FDA approval of sotorasib, a specific inhibitor of KRAS G12C mutant protein. We will discuss the efficacy and toxicities of the novel KRAS G12C inhibitors as well as other indirect strategies for targeting oncogenic KRAS mutations. We will review the limited literature on acquired resistance to these inhibitors and the novel combinatorial treatment strategies that are being tested currently in clinical trials.

Clinical efficacy of atezolizumab plus bevacizumab and chemotherapy in KRAS-mutated non-small cell lung cancer with STK11, KEAP1, or TP53 comutations: subgroup results from the phase III IMpower150 trial

Background

The efficacy of atezolizumab (A) and/or bevacizumab (B) with carboplatin/paclitaxel (CP) chemotherapy was explored in the phase III, randomized IMpower150 study in patients with non-squamous non-small cell lung cancer (NSCLC) according to KRAS mutations (mKRAS) and co-occurring STK11, KEAP1, or TP53 mutations.

Methods

Mutation status was determined by circulating tumor DNA next-generation sequencing. Overall survival (OS) and progression-free survival (PFS) were analyzed in a mutation-evaluable intention-to-treat population (MEP; n=920) and SP263 (programmed cell death ligand 1 (PD-L1)) biomarker-evaluable population (n=774).

Results

Within the mKRAS population (24.5% of MEP), ABCP showed numerical improvements vs BCP in median OS (19.8 vs 9.9 months; HR 0.50; 95% CI 0.34 to 0.72) and PFS (8.1 vs 5.8 months; HR 0.42; 95% CI 0.29 to 0.61)—greater than with ACP (OS: 11.7 vs 9.9 months; HR 0.63; 95% CI 0.43 to 0.91; PFS: 4.8 vs 5.8 months; HR 0.80; 95% CI 0.56 to 1.13) vs BCP. Across PD-L1 subgroups in mKRAS patients, OS and PFS were longer with ABCP vs BCP, but OS with ACP was similar to BCP in PD-L1-low and PD-L1-negative subgroups. Conversely, in KRAS-WT patients, OS was longer with ACP than with ABCP or BCP across PD-L1 subgroups. KRAS was frequently comutated with STK11, KEAP1, and TP53; these subgroups conferred different prognostic outcomes. Within the mKRAS population, STK11 and/or KEAP1 mutations were associated with inferior OS and PFS across treatments compared with STK11-WT and/or KEAP1-WT. In mKRAS patients with co-occurring mSTK11 and/or mKEAP1 (44.9%) or mTP53 (49.3%), survival was longer with ABCP than with ACP or BCP.

Conclusions

These analyses support previous findings of mutation of STK11 and/or KEAP1 as poor prognostic indicators. While clinical efficacy favored ABCP and ACP vs BCP in these mutational subgroups, survival benefits were greater in the mKRAS and KEAP1-WT and STK11-WT population vs mKRAS and mKEAP1 and mSTK11 population, suggesting both prognostic and predictive effects. Overall, these results suggest that atezolizumab combined with bevacizumab and chemotherapy is an efficacious first-line treatment in metastatic NSCLC subgroups with mKRAS and co-occurring STK11 and/or KEAP1 or TP53 mutations and/or high PD-L1 expression.

Targeted Therapies for Lung Cancer Patients With Oncogenic Driver Molecular Alterations

Lung cancer has traditionally been classified by histology. However, a greater understanding of disease biology and the identification of oncogenic driver alterations has dramatically altered the therapeutic landscape. Consequently, the new classification paradigm of non-small-cell lung cancer is further characterized by molecularly defined subsets actionable with targeted therapies and the treatment landscape is becoming increasingly complex. This review encompasses the current standards of care for targeted therapies in lung cancer with driver molecular alterations. Targeted therapies for EGFR exon 19 deletion and L858R mutations, and ALK and ROS1 rearrangements are well established. However, there is an expanding list of approved targeted therapies including for BRAF V600E, EGFR exon 20 insertion, and KRAS G12C mutations, MET exon 14 alterations, and NTRK and RET rearrangements. In addition, there are numerous other oncogenic drivers, such as HER2 exon 20 insertion mutations, for which there are emerging efficacy data for targeted therapies. The importance of diagnostic molecular testing, intracranial efficacy of novel therapies, the optimal sequencing of therapies, role for targeted therapies in early-stage disease, and future directions for precision oncology approaches to understand tumor evolution and therapeutic resistance are also discussed.

Real-World Time on Treatment with First-Line Pembrolizumab Monotherapy for Advanced NSCLC with PD-L1 Expression ≥ 50%: 3-Year Follow-Up Data

Simple Summary

Lung cancer is the leading cause of cancer-related death in the United States (US), and real-world studies are needed to understand effectiveness of cancer therapies for patients treated outside of cancer clinical trials. Pembrolizumab, an immunotherapy agent that aids the body’s immune system in fighting cancer, is administered for up to 2 years when treating advanced non-small cell lung cancer (NSCLC). We evaluated the real-world time on treatment (rwToT), a surrogate indicator that has been associated with survival in NSCLC studies, for over 1000 patients with advanced NSCLC treated initially with pembrolizumab at US oncology clinics. The median rwToT for patients with good performance status (similar to those in clinical trials) was 7.4 months, consistent with the median treatment duration in the KEYNOTE-024 trial (7.9 months). Our findings suggest long-term benefit of first-line pembrolizumab for patients with advanced NSCLC and good performance status at the start of therapy who are treated in real-world settings.

Abstract

Our aim was to evaluate real-world time on treatment (rwToT), overall and by KRAS mutation status, with first-line pembrolizumab monotherapy for advanced non-small cell lung cancer (NSCLC) in real-world oncology practice in the US. rwToT is a readily available, intermediate-range endpoint that is moderately to highly correlated with overall survival in clinical trials and real-world data. Using deidentified electronic medical record data, we studied patients with ECOG performance status (PS) of 0–2 who initiated pembrolizumab (1 November 2016 to 31 March 2020) for advanced NSCLC with programmed death-ligand 1 (PD-L1) expression ≥ 50% and without EGFR/ALK/ROS1 genomic alterations. The data cutoff was 31 March 2021, and the median study follow-up was 34 months. The Kaplan–Meier median rwToT with first-line pembrolizumab monotherapy was 7.4 months (95% CI, 6.3–8.1) for 807 patients with PS 0–1, which was consistent with the median treatment duration in the KEYNOTE-024 trial (7.9 months). The median rwToT for 237 patients with PS 2 was 2.1 months (95% CI, 1.4–2.8). For those with KRAS-mutated and KRAS wild-type nonsquamous NSCLC and PS 0–1, the median rwToT was 7.6 months and 7.0 months, respectively. Our findings suggest long-term benefit of first-line pembrolizumab monotherapy for advanced NSCLC with PD-L1 expression ≥ 50% in real-world settings in the US, particularly for patients with good performance status at the start of therapy, irrespective of KRAS status.

Targeting KRAS in Non-Small Cell Lung Cancer

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) is the most frequently altered oncogene in Non-Small Cell Lung Cancer (NSCLC). KRAS mutant tumors constitute a heterogeneous group of diseases, different from other oncogene-derived tumors in terms of biology and response to treatment, which hinders the development of effective drugs against KRAS. Therefore, for decades, despite enormous efforts invested in the development of drugs aimed at inhibiting KRAS or its signaling pathways, KRAS was considered to be undruggable. Recently, the discovery of a new pocket under the effector binding switch II region of KRAS G12C has allowed the development of direct KRAS inhibitors such as sotorasib, the first FDA-approved drug targeting KRAS G12C, or adagrasib, initiating a new exciting era. However, treatment with targeted KRAS G12C inhibitors also leads to resistance, and understanding the possible mechanisms of resistance and which drugs could be useful to overcome it is key. Among others, KRAS G12C (ON) tricomplex inhibitors and different combination therapy strategies are being analyzed in clinical trials. Another area of interest is the potential role of co-mutations in treatment selection, particularly immunotherapy. The best first-line strategy remains to be determined and, due to the heterogeneity of KRAS, is likely to be based on combination therapies.

The efficacy of immune checkpoint inhibitors in thoracic malignancies

The advent of immune checkpoint inhibitors (ICIs) has rapidly transformed the treatment paradigm for multiple cancer types, including thoracic malignancies. In advanced non-small cell lung cancer (NSCLC), ICIs have shifted treatment paradigm and improved overall survival reaching almost one-third of patients alive at 5 years. ICIs therapies have also modified the therapeutic strategy in first-line setting in metastatic small-cell lung cancer (SCLC) patients as well as in malignant pleural mesothelioma (MPM) improving the overall survival compared with standard treatment. This phenomenon is of huge relevance as both SCLC and MPM were considered orphan diseases without any significant improvement in the therapeutic strategy in the first-line setting during the last 15 years. In this review, we aim to review the efficacy of ICI in thoracic malignancies either in monotherapy or in combination, according to predictive biomarkers, and to the US Food and Drug Administration and the European Medicines Agency approvals of treatment strategies. We address the efficacy of these agents, especially in NSCLC according to PD-L1 expression and histologic subtype.

Updates on Molecular Targeted Therapies for Intraparenchymal CNS Metastases

Simple Summary

Metastatic disease to the central nervous system is an advanced-stage complication with historically devastating consequences and high mortality. Significant progress has been made in treatment in the last two decades, especially with the identification and targeting of specific mutations in the cancer pathway. In this review, we provide an updated overview of specific targets and highlight the numerous drugs that have demonstrated penetration and efficacy within the central nervous system.

Abstract

Central nervous system (CNS) metastases can occur in a high percentage of systemic cancer patients and is a major cause of morbidity and mortality in these patients. Almost any histology can find its way to the brain, but lung, breast, and melanoma are the most common pathologies seen in the CNS from metastatic disease. Identification of many key targets in the tumorigenesis pathway has been crucial to the development of a number of drugs that have demonstrated successful penetration of the blood–brain, blood–cerebrospinal fluid, and blood–tumor barriers. Targeted therapy and immunotherapy have dramatically revolutionized the field with treatment options that can provide successful and durable control of even CNS disease. In this review, we discuss major targets with successful treatment options as demonstrated in clinical trials. These include tyrosine kinase inhibitors, monoclonal antibodies, and antibody–drug conjugates. We also provide an update on the state of the field and highlight key upcoming trials. Patient-specific molecular information combined with novel therapeutic approaches and new agents has demonstrated and continues to promise significant progress in the management of patients with CNS metastases.

Immunotherapy in Non-Small Cell Lung Cancer With Actionable Mutations Other Than EGFR

While first line targeted therapies are the current standard of care treatment for non-small cell lung cancer (NSCLC) with actionable mutations, the cancer cells inevitably acquire resistance to these agents over time. Immune check-point inhibitors (ICIs) have improved the outcomes of metastatic NSCLC, however, its efficacy in those with targetable drivers is largely unknown. In this manuscript, we reviewed the published data on ICI therapies in NSCLC with ALK, ROS1, BRAF, c-MET, RET, NTRK, KRAS, and HER2 (ERBB2) alterations. We found that the objective response rates (ORRs) associated with ICI treatments in lung cancers harboring the BRAF (0-54%), c-MET (12-49%), and KRAS (18.7-66.7%) alterations were comparable to non-mutant NSCLC, whereas the ORRs in RET fusion NSCLC (less than10% in all studies but one) and ALK fusion NSCLC (0%) were relatively low. The ORRs reported in small numbers of patients and studies of ROS1 fusion, NTRK fusion, and HER 2 mutant NSCLC were 0-17%, 50% and 7-23%, respectively, making the efficacy of ICIs in these groups of patients less clear. In most studies, no significant correlation between treatment outcome and PD-L1 expression or tumor mutation burden (TMB) was identified, and how to select patients with NSCLC harboring actionable mutations who will likely benefit from ICI treatment remains unknown.

KRAS-G12C covalent inhibitors: A game changer in the scene of cancer therapies

RAS is the most frequently mutated oncogene in human cancer. Scientists attempted for decades to target this protein or its pathways, however, all the attempts failed and RAS was labeled as "undruggable". With KRAS-G12C covalent inhibitors entering clinical trials, the myth of this "undruggable" RAS is fading away. In 2021, the Food and Drug Administration (FDA) approved the use of Sotorasib (Lumakras) for the treatment of adult patients with KRAS-G12C mutated locally advanced or metastatic NSCLC, following at least one prior systemic therapy. However, and as every other drug, KRAS-G12C inhibitors are facing intrinsic and acquired resistances. In order to overcome these resistances, researchers are now working on combination strategies. Furthermore, studies are currently ongoing to better elucidate the status of KRAS-G12C as a predictive and prognostic tool and to strengthen its role in the field of personalized medicine.

Computational Biological Modeling Identifies PD-(L)1 Immunotherapy Sensitivity Among Molecular Subgroups of KRAS-Mutated Non-Small-Cell Lung Cancer

PURPOSE

KRAS-mutated (KRAS^MUT) non-small-cell lung cancer (NSCLC) is emerging as a heterogeneous disease defined by comutations, which may confer differential benefit to PD-(L)1 immunotherapy. In this study, we leveraged computational biological modeling (CBM) of tumor genomic data to identify PD-(L)1 immunotherapy sensitivity among KRAS^MUT NSCLC molecular subgroups.

MATERIALS AND METHODS

In this multicohort retrospective analysis, the genotype clustering frequency ranked method was used for molecular clustering of tumor genomic data from 776 patients with KRAS^MUT NSCLC. These genomic data were input into the CBM, in which customized protein networks were characterized for each tumor. The CBM evaluated sensitivity to PD-(L)1 immunotherapy using three metrics: programmed death-ligand 1 expression, dendritic cell infiltration index (nine chemokine markers), and immunosuppressive biomarker expression index (14 markers).

RESULTS

Genotype clustering identified eight molecular subgroups and the CBM characterized their shared cancer pathway characteristics: KRAS^MUT/TP53^MUT, KRAS^MUT/CDKN2A/B/C^MUT, KRAS^MUT/STK11^MUT, KRAS^MUT/KEAP1^MUT, KRAS^MUT/STK11^MUT/KEAP1^MUT, KRAS^MUT/PIK3CA^MUT, KRAS ^MUT/ATM^MUT, and KRAS^MUT without comutation. CBM identified PD-(L)1 immunotherapy sensitivity in the KRAS^MUT/TP53^MUT, KRAS^MUT/PIK3CA^MUT, and KRAS^MUT alone subgroups and resistance in the KEAP1^MUT containing subgroups. There was insufficient genomic information to elucidate PD-(L)1 immunotherapy sensitivity by the CBM in the KRAS^MUT/CDKN2A/B/C^MUT, KRAS^MUT/STK11^MUT, and KRAS^MUT/ATM^MUT subgroups. In an exploratory clinical cohort of 34 patients with advanced KRAS^MUT NSCLC treated with PD-(L)1 immunotherapy, the CBM-assessed overall survival correlated well with actual overall survival (r = 0.80, P < .001).

CONCLUSION

CBM identified distinct PD-(L)1 immunotherapy sensitivity among molecular subgroups of KRAS^MUT NSCLC, in line with previous literature. These data provide proof-of-concept that computational modeling of tumor genomics could be used to expand on hypotheses from clinical observations of patients receiving PD-(L)1 immunotherapy and suggest mechanisms that underlie PD-(L)1 immunotherapy sensitivity.

Abemaciclib in Combination With Pembrolizumab for Stage IV KRAS-Mutant or Squamous NSCLC: A Phase 1b Study

INTRODUCTION

Abemaciclib is an oral, selective small-molecule CDK 4 and 6 inhibitor. In preclinical models, abemaciclib synergized with programmed cell death protein-1 blockade to enhance antitumor efficacy. Here, we report the safety and anticancer activity of abemaciclib plus pembrolizumab in two cohorts with NSCLC.

METHODS

This nonrandomized, open-label, phase 1b study included patients with previously untreated programmed death-ligand 1-positive, KRAS-mutant nonsquamous metastatic NSCLC (cohort A); squamous NSCLC after one previous platinum-containing chemotherapy regimen for metastatic disease (cohort B); and two breast cancer cohorts (disclosed separately). Patients received 150 mg abemaciclib every 12 hours plus 200 mg pembrolizumab intravenously on day 1 every 21 days. The primary objective was safety; secondary objectives included objective response rate, disease control rate, progression-free survival, and overall survival. Clinical Trial Number: NCT02779751.

RESULTS

Each cohort enrolled 25 patients. Grades greater than or equal to 3 treatment-emergent adverse events in cohorts A and B were reported by 20 (80%) and 19 patients (76%), respectively. Six patients in cohort A (24.0%) and two patients in cohort B (8.0%) had a confirmed partial response; disease control rate was 56% and 64%, respectively. Median progression-free survival was 7.6 months (95% confidence interval [CI]: 1.6-not estimable) and 3.3 months (95% CI: 1.4-5.2); median overall survival was 27.8 months (95% CI: 9.9-not estimable) and 6.0 months (95% CI: 3.7-13.1) in cohorts A and B, respectively.

CONCLUSIONS

The combination of abemaciclib and pembrolizumab in stage IV NSCLC resulted in greater toxicity compared with that previously reported for each individual treatment. Risk-benefit profile does not warrant further evaluation of the combination in this population.

Prognostic Characteristics and Immunotherapy Response of Patients With Nonsquamous NSCLC With Kras Mutation in East Asian Populations: A Single-Center Cohort Study in Taiwan

Introduction

Kras mutation is the most common driver oncogene present in patients with NSCLC. Recently, the precision medicine for patients with Kras-mutated NSCLC has been under investigation, but the best treatment is still unknown. This study aimed to analyze the clinical characteristics, immune checkpoint inhibitor (ICI) response, and prognostic factors of patients with NSCLC with different Kras mutation subtypes.

Methods

From 2005 to 2018, we collected nonsquamous NSCLC tissue samples for Kras mutation analysis using direct Sanger sequencing or MassARRAY genotyping (Agena Bioscience, San Diego, CA) at the National Taiwan University Hospital. Clinical characteristics, ICI treatment effectiveness, time-to-tumor recurrence (TTR), and overall survival (OS) were analyzed using multivariate Cox models, to estimate adjusted hazard ratios (HRs).

Results

Among 5278 patients with nonsquamous NSCLC, 246 (4.7%) had Kras mutations. The major Kras mutation subtypes were G12C (32.9%), G12D (23.7%), and G12V (18.9%). Patients with Kras-G12C had a higher proportion of male individuals (p = 0.018) and smokers (p < 0.001). Among the 25 patients treated with ICIs, patients with Kras-G12C had a higher response rate (53.8% versus 8.3%, p = 0.030) and longer progression-free survival (4.8 mo versus 2.1 mo, p = 0.028) than those with Kras-non-G12C. For the 85 patients with early-stage NSCLC, those with G12C had shorter TTR (22.8 mo) than those with Kras-non-G12C (97.7 mo, p = 0.004). For the 143 patients with advanced-stage NSCLC, there was a significant difference in OS between patients with Kras-G12C and Kras-non-G12C (7.7 mo versus 6.0 mo, p = 0.018) and patients with Kras-G12V had the shortest OS (5.2 mo). Multivariate analysis revealed association of shorter OS with Kras-G12V (HR = 2.47, p = 0.002), stage IV disease status (HR = 2.69, p = 0.008), and NSCLC-not otherwise specified histology (HR = 3.12, p = 0.002).

Conclusions

Kras-G12C was associated with favorable ICI treatment effectiveness in patients with NSCLC. Kras-G12C mutation was associated with shorter TTR in patients with early-stage NSCLC, and Kras-G12V mutation was associated with shorter OS in patients with advanced-stage NSCLC when comparing with Kras-G12C.

Anti-PD-(L)1 for KRAS-mutant advanced non-small-cell lung cancers: a meta-analysis of randomized-controlled trials

PURPOSE

The most frequent mutation in advanced non-small-cell lung cancer (NSCLC), Kirsten rat-sarcoma viral oncogene (KRAS) is found in 20-25% of these patients' tumors. While phase III trials on therapies targeting KRAS, especially KRAS^G12C, are ongoing, the clinical efficacy of anti-programmed death protein-1 (PD-1) or its ligand (PD-L1) against KRAS-mutant NSCLCs remains a topic of debate.

METHODS

This meta-analysis examined randomized-trial data comparing first- or second-line anti-PD-(L)1 with or without chemotherapy vs. chemotherapy alone for advanced KRAS-mutant NSCLCs. Outcome measures included overall survival (OS) and progression-free survival (PFS). Analyses were computed using the Cochrane method of collaboration for meta-analyses, with Review Manager software (RevMan version 5.3; Oxford, UK).

RESULTS

We analyzed 3 first-line trials (IMpower-150, Keynote-189 and Keynote-042) and 3 second-line trials (Oak, Poplar and CheckMate-057) that included 1313 NSCLCs (386 KRAS-mutant and 927 KRAS wild-type tumors). For KRAS-mutant NSCLCs, anti-PD-(L)1 with or without chemotherapy was significantly associated (hazard ratio [95% confidence interval]) with prolonged OS (0.59 [0.49-0.72]; p < 0.00001) and PFS (0.58 [0.43-0.78]; p = 0.0003) compared to chemotherapy alone. OS benefited in both first- and second-line trials. OS for patients with KRAS-mutant NSCLCs was significantly longer than that for those with KRAS wild-type tumors (p = 0.001).

CONCLUSIONS

Anti-PD-(L)1 with or without chemotherapy seemed to achieve longer OS and PFS than chemotherapy alone for patients with KRAS-mutant and wild-type KRAS advanced NSCLCs, with an even greater OS benefit for the former.

Efficacy of immunotherapy in KRAS-mutant non-small-cell lung cancer with comutations

KRAS-mutant non-small-cell lung cancer is the most common molecular driver of lung adenocarcinoma in western populations. No KRAS specific therapy has been approved by the US FDA until 2021. Despite significant heterogeneity in comutations, patients typically receive single-agent immunotherapy or chemoimmunotherapy as standard first-line therapy. It is unclear whether KRAS mutations predict outcomes with immunotherapy; however, there is emerging data suggesting improved outcomes in patients with a TP53 comutation and worse outcomes in patients with a STK11/LKB1 or KEAP1 comutation.

Targeting KRAS in non-small-cell lung cancer: recent progress and new approaches

Rat sarcoma (RAS) is the most frequently mutated oncogene in human cancer, with Kirsten rat sarcoma (KRAS) being the most commonly mutated RAS isoform. Overall, KRAS accounts for 85% of RAS mutations observed in human cancers and is present in 35% of lung adenocarcinomas (LUADs). While the use of targeted therapies and immune checkpoint inhibitors (CPIs) has drastically changed the treatment landscape of advanced non-small-cell lung cancer (NSCLC) in recent years, historic attempts to target KRAS (both direct and indirect approaches) have had little success, and no KRAS-specific targeted therapies have been approved to date for patients in this molecular subset of NSCLC. With the discovery by Ostrem, Shokat, and colleagues of the switch II pocket on the surface of the active and inactive forms of KRAS, we now have an improved understanding of the complex interactions involved in the RAS family of signaling proteins which has led to the development of a number of promising direct KRAS^G12C inhibitors, such as sotorasib and adagrasib. In previously treated patients with KRAS^G12C-mutant NSCLC, clinical activity has been shown for both sotorasib and adagrasib monotherapy; these data suggest promising new treatment options are on the horizon. With the stage now set for a new era in the treatment of KRAS^G12C-mutated NSCLC, many questions remain to be answered in order to further elucidate the mechanisms of resistance, how best to use combination strategies, and if KRAS^G12C inhibitors will have suitable activity in earlier lines of therapy for patients with advanced/metastatic NSCLC.