Immune-Related Colitis Is Associated with Fecal Microbial Dysbiosis and Can Be Mitigated by Fecal Microbiota Transplantation.

Colitis induced by treatment with immune-checkpoint inhibitors (ICI), termed irColitis, is a substantial cause of morbidity complicating cancer treatment. We hypothesized that abnormal fecal microbiome features would be present at the time of irColitis onset and that restoring the microbiome with fecal transplant from a healthy donor would mitigate disease severity. Herein, we present fecal microbiota profiles from 18 patients with irColitis from a single center, 5 of whom were treated with healthy-donor fecal microbial transplantation (FMT). Although fecal samples collected at onset of irColitis had comparable α-diversity to that of comparator groups with gastrointestinal symptoms, irColitis was characterized by fecal microbial dysbiosis. Abundances of Proteobacteria were associated with irColitis in multivariable analyses. Five patients with irColitis refractory to steroids and biologic anti-inflammatory agents received healthy-donor FMT, with initial clinical improvement in irColitis symptoms observed in four of five patients. Two subsequently exhibited recurrence of irColitis symptoms following courses of antibiotics. Both received a second "salvage" FMT that was, again, followed by clinical improvement of irColitis. In summary, we observed distinct microbial community changes that were present at the time of irColitis onset. FMT was followed by clinical improvements in several cases of steroid- and biologic-agent-refractory irColitis. Strategies to restore or prevent microbiome dysbiosis in the context of immunotherapy toxicities should be further explored in prospective clinical trials.

Multi-institutional analysis of aneuploidy and outcomes to chemoradiation and durvalumab in stage III non-small cell lung cancer.

There is a need to identify predictive biomarkers to guide treatment strategies in stage III non-small cell lung cancer (NSCLCs). In this multi-institutional cohort of 197 patients with stage III NSCLC treated with concurrent chemoradiation (cCRT) and durvalumab consolidation, we identify that low tumor aneuploidy is independently associated with prolonged progression-free survival (HR 0.63; p=0.03) and overall survival (HR 0.50; p=0.03). Tumors with high aneuploidy had a significantly greater incidence of distant metastasis and shorter median distant-metastasis free survival (p=0.04 and p=0.048, respectively), but aneuploidy level did not associate with local-regional outcomes. Multiplexed immunofluorescence analysis in a cohort of NSCLC found increased intratumoral CD8-positive, PD-1-positive cells, double-positive PD-1 CD8 cells, and FOXP3-positive T-cell in low aneuploid tumors. Additionally, in a cohort of 101 patients treated with cCRT alone, tumor aneuploidy did not associate with disease outcomes. These data support the need for upfront treatment intensification strategies in stage III NSCLC patients with high aneuploid tumors and suggest that tumor aneuploidy is a promising predictive biomarker.

Two Cases of Durable and Deep Responses to Immune Checkpoint Inhibition-Refractory Metastatic Melanoma after Addition of Camu Camu Prebiotic.

Camu camu (CC) is a prebiotic that selectively stimulates growth and activity of beneficial gut microbiota. Work in murine models demonstrated that castalagin, the active compound in CC, preferentially binds to beneficial gut microbiome bacteria, promoting a stronger CD8+T cell anti-cancer response. We present two patients with metastatic melanoma whose cancer progressed on immune checkpoint inhibitors (ICIs) and developed clinically significant immune-related adverse events (irAEs). They were rechallenged with ICIs in combination with CC. The first patient is a 71-year-old woman with metastatic melanoma, whose ICI treatment was complicated by immune-related pneumonitis and colitis. Upon progression on maintenance nivolumab, CC was added to nivolumab, leading to a near complete response (CR). The second patient is a 90-year-old man with recurrent unresectable melanoma, treated with nivolumab, complicated by immune-related rash and diabetes. He developed new subcutaneous calf lesions and a metastatic popliteal lymph node. CC was added to nivolumab. One month later, the patient experienced a CR. Both patients have been on nivolumab and CC with durable responses for more than a year, with minimal irAEs. These two cases suggest that CC may modulate the microbiome, synergizing with ICIs to produce deep, durable responses with minimal irAEs.

Characterization and description of Gabonibacter chumensis sp. nov., isolated from feces of a patient with non-small cell lung cancer treated with immunotherapy.

A polyphasic taxonomic approach, incorporating analysis of phenotypic features, cellular fatty acid profiles, 16S rRNA gene sequences, and determination of average nucleotide identity (ANI) plus digital DNA-DNA hybridization (dDDH), was applied to characterize an anaerobic bacterial strain designated KD22T isolated from human feces. 16S rRNA gene-based phylogenetic analysis showed that strain KD22T was found to be most closely related to species of the genus Gabonibacter. At the 16S rRNA gene level, the closest species from the strain KD22T corresponded with Gabonibacter massiliensis GM7T, with a similarity of 97.58%. Cells of strain KD22T were Gram-negative coccobacillus, positive for indole and negative for catalase, nitrate reduction, oxidase, and urease activities. The fatty acid analysis demonstrated the presence of a high concentration of iso-C15: 0 (51.65%). Next, the complete whole-genome sequence of strain KD22T was 3,368,578 bp long with 42 mol% of DNA G + C contents. The DDH and ANI values between KD22T and type strains of phylogenetically related species were 67.40% and 95.43%, respectively. These phylogenetic, phenotypic, and genomic results supported the affiliation of strain KD22T as a novel bacterial species within the genus Gabonibacter. The proposed name is Gabonibacter chumensis and the type strain is KD22T (= CSUR Q8104T = DSM 115208 T).

Outcomes of Combination Platinum-Doublet Chemotherapy and Anti-PD(L)-1 Blockade in KRASG12C-Mutant Non-Small Cell Lung Cancer.

BACKGROUND: Direct KRASG12C inhibitors are approved for patients with non-small cell lung cancers (NSCLC) in the second-line setting. The standard-of-care for initial treatment remains immune checkpoint inhibitors, commonly in combination with platinum-doublet chemotherapy (chemo-immunotherapy). Outcomes to chemo-immunotherapy in this subgroup have not been well described. Our goal was to define the clinical outcomes to chemo-immunotherapy in patients with NSCLC with KRASG12C mutations. PATIENTS AND METHODS: Through next-generation sequencing, we identified patients with advanced NSCLC with KRAS mutations treated with chemo-immunotherapy at 2 institutions. The primary objective was to determine outcomes and determinants of response to first-line chemo-immunotherapy among patients with KRASG12C by evaluating objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). We assessed the impact of coalterations in STK11/KEAP1 on outcomes. As an exploratory objective, we compared the outcomes to chemo-immunotherapy in KRASG12C versus non-G12C groups. RESULTS: One hundred and thirty eight patients with KRASG12C treated with first-line chemo-immunotherapy were included. ORR was 41% (95% confidence interval (CI), 32-41), median PFS was 6.8 months (95%CI, 5.5-10), and median OS was 15 months (95%CI, 11-28). In a multivariable model for PFS, older age (P = .042), squamous cell histology (P = .008), poor ECOG performance status (PS) (P < .001), and comutations in KEAP1 and STK11 (KEAP1MUT/STK11MUT) (P = .015) were associated with worse PFS. In a multivariable model for OS, poor ECOG PS (P = .004) and KEAP1MUT/STK11MUT (P = .009) were associated with worse OS. Patients with KRASG12C (N = 138) experienced similar outcomes to chemo-immunotherapy compared to patients with non-KRASG12C (N = 185) for both PFS (P = .2) and OS (P = .053). CONCLUSIONS: We define the outcomes to first-line chemo-immunotherapy in patients with KRASG12C, which provides a real-world benchmark for clinical trial design involving patients with KRASG12C mutations. Outcomes are poor in patients with specific molecular coalterations, highlighting the need to develop more effective frontline therapies.

Generalization optimizing machine learning to improve CT scan radiomics and assess immune checkpoint inhibitors' response in non-small cell lung cancer: a multicenter cohort study.

Background: Recent developments in artificial intelligence suggest that radiomics may represent a promising non-invasive biomarker to predict response to immune checkpoint inhibitors (ICIs). Nevertheless, validation of radiomics algorithms in independent cohorts remains a challenge due to variations in image acquisition and reconstruction. Using radiomics, we investigated the importance of scan normalization as part of a broader machine learning framework to enable model external generalizability to predict ICI response in non-small cell lung cancer (NSCLC) patients across different centers. Methods: Radiomics features were extracted and compared from 642 advanced NSCLC patients on pre-ICI scans using established open-source PyRadiomics and a proprietary DeepRadiomics deep learning technology. The population was separated into two groups: a discovery cohort of 512 NSCLC patients from three academic centers and a validation cohort that included 130 NSCLC patients from a fourth center. We harmonized images to account for variations in reconstruction kernel, slice thicknesses, and device manufacturers. Multivariable models, evaluated using cross-validation, were used to estimate the predictive value of clinical variables, PD-L1 expression, and PyRadiomics or DeepRadiomics for progression-free survival at 6 months (PFS-6). Results: The best prognostic factor for PFS-6, excluding radiomics features, was obtained with the combination of Clinical + PD-L1 expression (AUC = 0.66 in the discovery and 0.62 in the validation cohort). Without image harmonization, combining Clinical + PyRadiomics or DeepRadiomics delivered an AUC = 0.69 and 0.69, respectively, in the discovery cohort, but dropped to 0.57 and 0.52, in the validation cohort. This lack of generalizability was consistent with observations in principal component analysis clustered by CT scan parameters. Subsequently, image harmonization eliminated these clusters. The combination of Clinical + DeepRadiomics reached an AUC = 0.67 and 0.63 in the discovery and validation cohort, respectively. Conversely, the combination of Clinical + PyRadiomics failed generalizability validations, with AUC = 0.66 and 0.59. Conclusion: We demonstrated that a risk prediction model combining Clinical + DeepRadiomics was generalizable following CT scan harmonization and machine learning generalization methods. These results had similar performances to routine oncology practice using Clinical + PD-L1. This study supports the strong potential of radiomics as a future non-invasive strategy to predict ICI response in advanced NSCLC.

Fecal microbiota transplantation plus anti-PD-1 immunotherapy in advanced melanoma: a phase I trial.

Fecal microbiota transplantation (FMT) represents a potential strategy to overcome resistance to immune checkpoint inhibitors in patients with refractory melanoma; however, the role of FMT in first-line treatment settings has not been evaluated. We conducted a multicenter phase I trial combining healthy donor FMT with the PD-1 inhibitors nivolumab or pembrolizumab in 20 previously untreated patients with advanced melanoma. The primary end point was safety. No grade 3 adverse events were reported from FMT alone. Five patients (25%) experienced grade 3 immune-related adverse events from combination therapy. Key secondary end points were objective response rate, changes in gut microbiome composition and systemic immune and metabolomics analyses. The objective response rate was 65% (13 of 20), including four (20%) complete responses. Longitudinal microbiome profiling revealed that all patients engrafted strains from their respective donors; however, the acquired similarity between donor and patient microbiomes only increased over time in responders. Responders experienced an enrichment of immunogenic and a loss of deleterious bacteria following FMT. Avatar mouse models confirmed the role of healthy donor feces in increasing anti-PD-1 efficacy. Our results show that FMT from healthy donors is safe in the first-line setting and warrants further investigation in combination with immune checkpoint inhibitors. ClinicalTrials.gov identifier NCT03772899 .

Efficacy of PD-(L)1 blockade monotherapy compared with PD-(L)1 blockade plus chemotherapy in first-line PD-L1-positive advanced lung adenocarcinomas: a cohort study.

BACKGROUND: Single-agent PD-(L)1 blockade (IO) alone or in combination with chemotherapy (Chemotherapy-IO) is approved first-line therapies in patients with advanced lung adenocarcinomas (LUADs) with PD-L1 expression ≥1%. These regimens have not been compared prospectively. The primary objective was to compare first-line efficacies of single-agent IO to Chemotherapy-IO in patients with advanced LUADs. Secondary objectives were to explore if clinical, pathological, and genomic features were associated with differential response to Chemotherapy-IO versus IO. METHODS: This was a multicenter retrospective cohort study. Inclusion criteria were patients with advanced LUADs with tumor PD-L1 ≥1% treated with first-line Chemotherapy-IO or IO. To compare the first-line efficacies of single-agent IO to Chemotherapy-IO, we conducted inverse probability weighted Cox proportional hazards models using estimated propensity scores. RESULTS: The cohort analyzed included 866 patients. Relative to IO, Chemotherapy-IO was associated with improved objective response rate (ORR) (44% vs 35%, p=0.007) and progression-free survival (PFS) in patients with tumor PD-L1≥1% (HR 0.84, 95% CI 0.72 to 0.97, p=0.021) or PD-L1≥50% (ORR 55% vs 38%, p<0.001; PFS HR 0.68, 95% CI 0.53 to 0.87, p=0.002). Using propensity-adjusted analyses, only never-smokers in the PD-L1≥50% subgroup derived a differential survival benefit from Chemotherapy-IO vs IO (p=0.013). Among patients with very high tumor PD-L1 expression (≥90%), there were no differences in outcome between treatment groups. No genomic factors conferred differential survival benefit to Chemotherapy-IO versus IO. CONCLUSIONS: While the addition of chemotherapy to PD-(L)1 blockade increases the probability of initial response, never-smokers with tumor PD-L1≥50% comprise the only population identified that derived an apparent survival benefit with treatment intensification.

Clinical and Molecular Features of Long-term Response to Immune Checkpoint Inhibitors in Patients with Advanced Non-Small Cell Lung Cancer.

PURPOSE: We sought to identify features of patients with advanced non-small cell lung cancer (NSCLC) who achieve long-term response (LTR) to immune checkpoint inhibitors (ICI), and how these might differ from features predictive of short-term response (STR). EXPERIMENTAL DESIGN: We performed a multicenter retrospective analysis of patients with advanced NSCLC treated with ICIs between 2011 and 2022. LTR and STR were defined as response ≥ 24 months and response < 12 months, respectively. Tumor programmed death ligand 1 (PD-L1) expression, tumor mutational burden (TMB), next-generation sequencing (NGS), and whole-exome sequencing (WES) data were analyzed to identify characteristics enriched in patients achieving LTR compared with STR and non-LTR. RESULTS: Among 3,118 patients, 8% achieved LTR and 7% achieved STR, with 5-year overall survival (OS) of 81% and 18% among LTR and STR patients, respectively. High TMB (≥50th percentile) enriched for LTR compared with STR (P = 0.001) and non-LTR (P < 0.001). Whereas PD-L1 ≥ 50% enriched for LTR compared with non-LTR (P < 0.001), PD-L1 ≥ 50% did not enrich for LTR compared with STR (P = 0.181). Nonsquamous histology (P = 0.040) and increasing depth of response [median best overall response (BOR) -65% vs. -46%, P < 0.001] also associated with LTR compared with STR; no individual genomic alterations were uniquely enriched among LTR patients. CONCLUSIONS: Among patients with advanced NSCLC treated with ICIs, distinct features including high TMB, nonsquamous histology, and depth of radiographic improvement distinguish patients poised to achieve LTR compared with initial response followed by progression, whereas high PD-L1 does not.

Impact of TMB/PD-L1 expression and pneumonitis on chemoradiation and durvalumab response in stage III NSCLC.

Although concurrent chemoradiation (CRT) and durvalumab consolidation has become a standard treatment for stage III non-small cell lung cancer (NSCLC), clinicopathologic and genomic factors associated with its efficacy remain poorly characterized. Here, in a multi-institutional retrospective cohort study of 328 patients treated with CRT and durvalumab, we identify that very high PD-L1 tumor proportion score (TPS) expression ( ≥ 90%) and increased tumor mutational burden (TMB) are independently associated with prolonged disease control. Additionally, we identify the impact of pneumonitis and its timing on disease outcomes among patients who discontinue durvalumab: compared to patients who experienced early-onset pneumonitis ( < 3 months) leading to durvalumab discontinuation, patients with late-onset pneumonitis had a significantly longer PFS (12.7 months vs not reached; HR 0.24 [95% CI, 0.10 to 0.58]; P = 0.001) and overall survival (37.2 months vs not reached; HR 0.26 [95% CI, 0.09 to 0.79]; P = 0.017). These findings suggest that opportunities exist to improve outcomes in patients with lower PD-L1 and TMB levels, and those at highest risk for pneumonitis.

Tractidigestivibacter montrealensis sp. nov., a new member of human gut microbiota isolated from a healthy volunteer.

Strain KD21T, isolated from the fecal sample of a healthy female volunteer, is a strictly anaerobic, non-motile, Gram-staining-positive, saccharolytic small rod that does not produce spores. Strain KD21T was able to grow in the range of temperature 28°C-37°C (optimum, 37 °C), pH 6.0-8.0 (optimum, pH 7.0), and with 0-5.0 g/l NaCl (optimum, 0 g/l NaCl). Bacteria cells reduced nitrates to nitrites. Its major fatty acids were C18:1ω9c, C16:0, C18:0, and summed in feature 8 (C18:1ω7c and/or C18:1ω6c). 16S rRNA gene phylogenetic analysis revealed that KD21T is a member of the genus Tractidigestivibacter and is distinct from any species with validly published names. The sequence showed 98.48% similarity with T. scatoligenes SK9K4T. The DNA G + C content of strain KD21T was 62.6 mol%. The DNA-DNA hybridization and OrthoANI values between strain KD21T and T. scatoligenes SK9K4T were 40.2% and 90.2%, respectively. Differences in phenotypic, phylogenetic, chemotaxonomic, and genomic characteristics indicated that strain KD21T represents a novel species within the genus Tractidigestivibacter. The name T. montrealensis sp. nov. is proposed and the type strain is KD21T (= CSUR Q8103T =  DSM 115111T).

Combination Therapy With MDM2 and MEK Inhibitors Is Effective in Patient-Derived Models of Lung Adenocarcinoma With Concurrent Oncogenic Drivers and MDM2 Amplification.

INTRODUCTION: Although targeted therapies have revolutionized the therapeutic landscape of lung adenocarcinomas (LUADs), disease progression on single-agent targeted therapy against known oncogenic drivers is common, and therapeutic options after disease progression are limited. In patients with MDM2 amplification (MDM2amp) and a concurrent oncogenic driver alteration, we hypothesized that targeting of the tumor-suppressor pathway (by means of restoration of p53 using MDM2 inhibition) and simultaneous targeting of co-occurring MAPK oncogenic pathway might represent a more durably effective therapeutic strategy. METHODS: We evaluated genomic next-generation sequencing data using the Memorial Sloan Kettering Cancer Center-Integrated Mutation Profiling of Actionable Cancer Targets platform to nominate potential targets for combination therapy in LUAD. We investigated the small molecule MDM2 inhibitor milademetan in cell lines and patient-derived xenografts of LUAD with a known driver alteration and MDM2amp. RESULTS: Of 10,587 patient samples from 7121 patients with LUAD profiled by next-generation sequencing, 6% (410 of 7121) harbored MDM2amp. MDM2amp was significantly enriched among tumors with driver alterations in METex14 (36%, p < 0.001), EGFR (8%, p < 0.001), RET (12%, p < 0.01), and ALK (10%, p < 0.01). The combination of milademetan and the MEK inhibitor trametinib was synergistic in growth inhibition of ECLC5-GLx (TRIM33-RET/MDM2amp), LUAD12c (METex14/KRASG12S/MDM2amp), SW1573 (KRASG12C, TP53 wild type), and A549 (KRASG12S) cells and in increasing expression of proapoptotic proteins PUMA and BIM. Treatment of ECLC5-GLx and LUAD12c with single-agent milademetan increased ERK phosphorylation, consistent with previous data on ERK activation with MDM2 inhibition. This ERK activation was effectively suppressed by concomitant administration of trametinib. In contrast, ERK phosphorylation induced by milademetan was not suppressed by concurrent RET inhibition using selpercatinib (in ECLC5-GLx) or MET inhibition using capmatinib (in LUAD12c). In vivo, combination milademetan and trametinib was more effective than either agent alone in ECLC5-GLx, LX-285 (EGFRex19del/MDM2amp), L13BS1 (METex14/MDM2amp), and A549 (KRASG12S, TP53 wild type). CONCLUSIONS: Combined MDM2/MEK inhibition was found to have efficacy across multiple patient-derived LUAD models harboring MDM2amp and concurrent oncogenic drivers. This combination, potentially applicable to LUADs with a wide variety of oncogenic driver mutations and kinase fusions activating the MAPK pathway, has evident clinical implications and will be investigated as part of a planned phase 1/2 clinical trial.

Impact of Aneuploidy and Chromosome 9p Loss on Tumor Immune Microenvironment and Immune Checkpoint Inhibitor Efficacy in NSCLC.

INTRODUCTION: Although gene-level copy number alterations have been studied as a potential biomarker of immunotherapy efficacy in NSCLC, the impact of aneuploidy burden and chromosomal arm-level events on immune checkpoint inhibitor (ICI) efficacy in NSCLC is uncertain. METHODS: Patients who received programmed cell death protein 1 or programmed death-ligand 1 (PD-L1) inhibitor at two academic centers were included. Across all 22 chromosomes analyzed, an arm was considered altered if at least 70% of its territory was either gained or deleted. Among nonsquamous NSCLCs which underwent targeted next-generation sequencing, we retrospectively quantified aneuploidy using the adjusted fraction of chromosomal arm alterations (FAA), defined as the number of altered chromosome arms divided by the number of chromosome arms assessed, adjusted for tumor purity. RESULTS: Among 2293 nonsquamous NSCLCs identified, the median FAA increased with more advanced cancer stage and decreased with higher PD-L1 tumor proportion score (TPS) levels (median FAA in TPS < 1%: 0.09, TPS 1%-49%: 0.08, TPS ≥ 50%: 0.05, p < 0.0001). There was a very weak correlation between FAA and tumor mutational burden when taken as continuous variables (R: 0.07, p = 0.0005). A total of 765 advanced nonsquamous NSCLCs with available FAA values were treated with ICIs. With decreasing FAA tertiles, there was a progressive improvement in objective response rate (ORR 15.1% in upper tertile versus 23.2% in middle tertile versus 28.4% in lowest tertile, p = 0.001), median progression-free survival (mPFS 2.5 versus 3.3 versus 4.1 mo, p < 0.0001), and median overall survival (mOS 12.5 versus 13.9 versus 16.4 mo, p = 0.006), respectively. In the arm-level enrichment analysis, chromosome 9p loss (OR = 0.22, Q = 0.0002) and chromosome 1q gain (OR = 0.43, Q = 0.002) were significantly enriched in ICI nonresponders after false discovery rate adjustment. Compared with NSCLCs without chromosome 9p loss (n = 452), those with 9p loss (n = 154) had a lower ORR (28.1% versus 7.8%, p < 0.0001), a shorter mPFS (4.1 versus 2.3 mo, p < 0.0001), and a shorter mOS (18.0 versus 9.6 mo, p < 0.0001) to immunotherapy. In addition, among NSCLCs with high PD-L1 expression (TPS ≥ 50%), chromosome 9p loss was associated with lower ORR (43% versus 6%, p < 0.0001), shorter mPFS (6.4 versus 2.6 mo, p = 0.0006), and shorter mOS (30.2 versus 14.3 mo, p = 0.0008) to immunotherapy compared with NSCLCs without 9p loss. In multivariable analysis, adjusting for key variables including FAA, chromosome 9p loss, but not 1q gain, retained a significant impact on ORR (hazard ratio [HR] = 0.25, p < 0.001), mPFS (HR = 1.49, p = 0.001), and mOS (HR = 1.47, p = 0.003). Multiplexed immunofluorescence and computational deconvolution of RNA sequencing data revealed that tumors with either high FAA levels or chromosome 9p loss had significantly fewer tumor-associated cytotoxic immune cells. CONCLUSIONS: Nonsquamous NSCLCs with high aneuploidy and chromosome 9p loss have a distinct tumor immune microenvironment and less favorable outcomes to ICIs.

Following your gut: the emerging role of the gut microbiota in predicting and treating immune-related adverse events.

PURPOSE OF REVIEW: Although immune checkpoint inhibition has reshaped the therapeutic landscape leading to improved outcomes across an array of both solid and hematologic malignancies, a significant source of morbidity is caused by immune-related adverse events (irAEs) caused by these agents. RECENT FINDINGS: The gut microbiota has emerged as a biomarker of response to these agents, and more recently, also as a key determinant of development of irAEs. Emerging data have revealed that enrichment of certain bacterial genera is associated with an increased risk of irAEs, with the most robust evidence pointing to an intimate connection with the development of immune-related diarrhea and colitis. These bacteria include Bacteroides , Enterobacteriaceae, and Proteobacteria (such as Klebsiella and Proteus ) . Lachnospiraceae spp. and Streptococcus spp. have been implicated irAE-wide in the context of ipilimumab. SUMMARY: We review recent lines of evidence pointing to the role of baseline gut microbiota on the development of irAE, and the potentials for therapeutic manipulation of the gut microbiota in order to reduce irAE severity. The connections between gut microbiome signatures of response and toxicity will need to be untangled in further studies.

Clinicopathologic, Genomic, and Immunophenotypic Landscape of ATM Mutations in Non-Small Cell Lung Cancer.

PURPOSE: ATM is the most commonly mutated DNA damage and repair gene in non-small cell lung cancer (NSCLC); however, limited characterization has been pursued. EXPERIMENTAL DESIGN: Clinicopathologic, genomic, and treatment data were collected for 5,172 patients with NSCLC tumors which underwent genomic profiling. ATM IHC was performed on 182 NSCLCs with ATM mutations. Multiplexed immunofluorescence was performed on a subset of 535 samples to examine tumor-infiltrating immune cell subsets. RESULTS: A total of 562 deleterious ATM mutations were identified in 9.7% of NSCLC samples. ATM-mutant (ATMMUT) NSCLC was significantly associated with female sex (P = 0.02), ever smoking status (P < 0.001), non-squamous histology (P = 0.004), and higher tumor mutational burden (DFCI, P < 0.0001; MSK, P < 0.0001) compared with ATM-wild-type (ATMWT) cases. Among 3,687 NSCLCs with comprehensive genomic profiling, co-occurring KRAS, STK11, and ARID2 oncogenic mutations were significantly enriched among ATMMUT NSCLCs (Q < 0.05), while TP53 and EGFR mutations were enriched in ATMWT NSCLCs. Among 182 ATMMUT samples with ATM IHC, tumors with nonsense, insertions/deletions, or splice site mutations were significantly more likely to display ATM loss by IHC (71.4% vs. 28.6%; P < 0.0001) compared with tumors with only predicted pathogenic missense mutations. Clinical outcomes to PD-(L)1 monotherapy (N = 1,522) and chemo-immunotherapy (N = 951) were similar between ATMMUT and ATMWT NSCLCs. Patients with concurrent ATM/TP53 mutations had significantly improved response rate and progression-free survival with PD-(L)1 monotherapy. CONCLUSIONS: Deleterious ATM mutations defined a subset of NSCLC with unique clinicopathologic, genomic, and immunophenotypic features. Our data may serve as resource to guide interpretation of specific ATM mutations in NSCLC.

Clinicopathologic and Genomic Factors Impacting Efficacy of First-Line Chemoimmunotherapy in Advanced NSCLC.

INTRODUCTION: Although programmed cell death protein 1 and programmed death-ligand 1 (PD-L1) blockade in combination with platinum-doublet chemotherapy has become a mainstay of first-line treatment for advanced NSCLC, factors associated with efficacy of chemoimmunotherapy (CIT) are not well characterized. METHODS: In this multicenter retrospective analysis, clinicopathologic and genomic data were collected from patients with advanced NSCLC (lacking sensitizing genomic alterations in EGFR and ALK) and evaluated with clinical outcomes to first-line CIT. RESULTS: Among 1285 patients treated with CIT, a worsening performance status and increasing derived neutrophil-to-lymphocyte ratio in the blood were associated with a significantly reduced objective response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS). With increasing PD-L1 tumor proportion scores of less than 1%, 1% to 49%, 50% to 89%, and greater than or equal to 90%, there was a progressive improvement in ORR (32.7% versus 37.5% versus 51.6% versus 61.7%, p < 0.001), mPFS (5.0 versus 6.1 versus 6.8 versus 13.0 mo, p < 0.001), and generally mOS (12.9 versus 14.6 versus 34.7 versus 23.1 mo, p = 0.009), respectively. Of 789 NSCLCs with comprehensive genomic data, NSCLCs with a tumor mutational burden (TMB) greater than or equal to the 90th percentile had an improved ORR (53.5% versus 36.4%, p = 0.004), mPFS (10.8 versus 5.5 mo, p < 0.001), and mOS (29.2 versus 13.1 mo, p < 0.001), compared with those with a TMB less than the 90th percentile. In all-comers with nonsquamous NSCLC, the presence of an STK11, KEAP1, or SMARCA4 mutation was associated with significantly worse ORR, mPFS, and mOS to CIT (all p < 0.05); this was also observed in the KRAS-mutant subgroup of NSCLCs with co-occurring mutations in STK11, KEAP1, or SMARCA4 (all p < 0.05). In KRAS wild-type NSCLC, KEAP1 and SMARCA4 mutations were associated with a significantly shorter mPFS and mOS to CIT (all p < 0.05), but STK11 mutation status had no significant impact on mPFS (p = 0.16) or mOS (p = 0.38). CONCLUSIONS: In advanced NSCLC, better patient performance status, low derived neutrophil-to-lymphocyte ratio, increasing PD-L1 expression, a very high TMB, and STK11/KEAP1/SMARCA4 wild-type status are associated with improved clinical outcomes to first-line CIT.

Brief Report: Combination of Osimertinib and Dacomitinib to Mitigate Primary and Acquired Resistance in EGFR-Mutant Lung Adenocarcinomas.

PURPOSE: Primary and acquired resistance to osimertinib remain significant challenges for patients with EGFR-mutant lung cancers. Acquired EGFR alterations such as EGFR T790M or C797S mediate resistance to EGFR tyrosine kinase inhibitors (TKI) and combination therapy with dual EGFR TKIs may prevent or reverse on-target resistance. PATIENTS AND METHODS: We conducted two prospective, phase I/II trials assessing combination osimertinib and dacomitinib to address on-target resistance in the primary and acquired resistance settings. In the initial therapy study, patients received dacomitinib and osimertinib in combination as initial therapy. In the acquired resistance trial, dacomitinib with or without osimertinib was administered to patients with EGFR-mutant lung cancers with disease progression on osimertinib alone and evidence of an acquired EGFR second-site mutation. RESULTS: Cutaneous toxicities occurred in 93% (any grade) of patients and diarrhea in 72% (any grade) with the combination. As initial therapy, the overall response to the combination was 73% [95% confidence interval (CI), 50%-88%]. No acquired secondary alterations in EGFR were observed in any patients at progression. In the acquired resistance setting, the overall response was 14% (95% CI, 1%-58%). CONCLUSIONS: We observed no acquired secondary EGFR alterations with dual inhibition of EGFR as up-front treatment, but this regimen was associated with greater toxicity. The combination was not effective in reversing acquired resistance after development of a second-site acquired EGFR alteration. Our study highlights the need to develop better strategies to address on-target resistance in patients with EGFR-mutant lung cancers.

Interplay of Immunosuppression and Immunotherapy Among Patients With Cancer and COVID-19.

Importance: Cytokine storm due to COVID-19 can cause high morbidity and mortality and may be more common in patients with cancer treated with immunotherapy (IO) due to immune system activation. Objective: To determine the association of baseline immunosuppression and/or IO-based therapies with COVID-19 severity and cytokine storm in patients with cancer. Design, Setting, and Participants: This registry-based retrospective cohort study included 12 046 patients reported to the COVID-19 and Cancer Consortium (CCC19) registry from March 2020 to May 2022. The CCC19 registry is a centralized international multi-institutional registry of patients with COVID-19 with a current or past diagnosis of cancer. Records analyzed included patients with active or previous cancer who had a laboratory-confirmed infection with SARS-CoV-2 by polymerase chain reaction and/or serologic findings. Exposures: Immunosuppression due to therapy; systemic anticancer therapy (IO or non-IO). Main Outcomes and Measures: The primary outcome was a 5-level ordinal scale of COVID-19 severity: no complications; hospitalized without requiring oxygen; hospitalized and required oxygen; intensive care unit admission and/or mechanical ventilation; death. The secondary outcome was the occurrence of cytokine storm. Results: The median age of the entire cohort was 65 years (interquartile range [IQR], 54-74) years and 6359 patients were female (52.8%) and 6598 (54.8%) were non-Hispanic White. A total of 599 (5.0%) patients received IO, whereas 4327 (35.9%) received non-IO systemic anticancer therapies, and 7120 (59.1%) did not receive any antineoplastic regimen within 3 months prior to COVID-19 diagnosis. Although no difference in COVID-19 severity and cytokine storm was found in the IO group compared with the untreated group in the total cohort (adjusted odds ratio [aOR], 0.80; 95% CI, 0.56-1.13, and aOR, 0.89; 95% CI, 0.41-1.93, respectively), patients with baseline immunosuppression treated with IO (vs untreated) had worse COVID-19 severity and cytokine storm (aOR, 3.33; 95% CI, 1.38-8.01, and aOR, 4.41; 95% CI, 1.71-11.38, respectively). Patients with immunosuppression receiving non-IO therapies (vs untreated) also had worse COVID-19 severity (aOR, 1.79; 95% CI, 1.36-2.35) and cytokine storm (aOR, 2.32; 95% CI, 1.42-3.79). Conclusions and Relevance: This cohort study found that in patients with cancer and COVID-19, administration of systemic anticancer therapies, especially IO, in the context of baseline immunosuppression was associated with severe clinical outcomes and the development of cytokine storm. Trial Registration: ClinicalTrials.gov Identifier: NCT04354701.