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Purpose:Neoadjuvant anti–PD-1 therapy has shown promise for resectable non–small cell lung cancer (NSCLC). We reported the first phase I/II trial of neoadjuvant nivolumab in resectable NSCLC, finding it to be safe and feasible with encouraging major pathological responses (MPR). We now present 5-year clinical outcomes from this trial, representing to our knowledge, the longest follow-up data for neoadjuvant anti–PD-1 in any cancer type.Patients and Methods:Two doses of nivolumab (3 mg/kg) were administered for 4 weeks before surgery to 21 patients with Stage I–IIIA NSCLC. 5-year recurrence-free survival (RFS), overall survival (OS), and associations with MPR and PD-L1, were evaluated.Results:With a median follow-up of 63 months, 5-year RFS and OS rates were 60% and 80%, respectively. The presence of MPR and pre-treatment tumor PD-L1 positivity (TPS ≥1%) each trended toward favorable RFS; HR, 0.61 [95% confidence interval (CI), 0.15–2.44] and HR, 0.36 (95% CI, 0.07–1.85), respectively. At 5-year follow-up, 8 of 9 (89%) patients with MPR were alive and disease-free. There were no cancer-related deaths among patients with MPR. In contrast, 6/11 patients without MPR experienced tumor relapse, and 3 died.Conclusions:Five-year clinical outcomes for neoadjuvant nivolumab in resectable NSCLC compare favorably with historical outcomes. MPR and PD-L1 positivity trended toward improved RFS, though definitive conclusions are limited by cohort size.

PurposeGene fusions involving receptor tyrosine kinases (RTKs) define an important class of genomic alterations with many successful targeted therapies now approved for ALK, ROS1, RET and NTRK gene fusions. Fusions involving the ERBB family of RTKs have been sporadically reported, but their frequency has not yet been comprehensively analyzed and functional characterization is lacking on many types of ERBB fusions.Materials and methodsWe analyzed tumor samples submitted to Caris Life Sciences (n=64,354), as well as the TCGA (n=10,967), MSK IMPACT (n=10,945) and AACR GENIE (n=96,324) databases for evidence of EGFR, ERBB2 and ERBB4 gene fusions. We also expressed several novel fusions in cancer cell lines and analyzed their response to EGFR and HER2 tyrosine kinase inhibitors (TKIs).ResultsIn total, we identified 1,251 ERBB family fusions, representing an incidence of approximately 0.7% across all cancer types. EGFR, ERBB2, and ERBB4 fusions were most frequently found in glioblastoma, breast cancer and ovarian cancer, respectively. We modeled two novel types of EGFR and ERBB2 fusions, one with a tethered kinase domain and the other with a tethered adapter protein. Specifically, we expressed EGFR-ERBB4, EGFR-SHC1, ERBB2-GRB7 and ERBB2-SHC1, in cancer cell lines and demonstrated that they are oncogenic, regulate downstream signaling and are sensitive to small molecule inhibition with EGFR and HER2 TKIs.ConclusionsWe found that ERBB fusions are recurrent mutations that occur across multiple cancer types. We also establish that adapter-tethered and kinase-tethered fusions are oncogenic and can be inhibited with EGFR or HER2 inhibitors. We further propose a nomenclature system to categorize these fusions into several functional classes.

Purpose:Neoadjuvant anti–PD-1 therapy has shown promise for resectable non–small cell lung cancer (NSCLC). We reported the first phase I/II trial of neoadjuvant nivolumab in resectable NSCLC, finding it to be safe and feasible with encouraging major pathological responses (MPR). We now present 5-year clinical outcomes from this trial, representing to our knowledge, the longest follow-up data for neoadjuvant anti–PD-1 in any cancer type.Patients and Methods:Two doses of nivolumab (3 mg/kg) were administered for 4 weeks before surgery to 21 patients with Stage I–IIIA NSCLC. 5-year recurrence-free survival (RFS), overall survival (OS), and associations with MPR and PD-L1, were evaluated.Results:With a median follow-up of 63 months, 5-year RFS and OS rates were 60% and 80%, respectively. The presence of MPR and pre-treatment tumor PD-L1 positivity (TPS ≥1%) each trended toward favorable RFS; HR, 0.61 [95% confidence interval (CI), 0.15–2.44] and HR, 0.36 (95% CI, 0.07–1.85), respectively. At 5-year follow-up, 8 of 9 (89%) patients with MPR were alive and disease-free. There were no cancer-related deaths among patients with MPR. In contrast, 6/11 patients without MPR experienced tumor relapse, and 3 died.Conclusions:Five-year clinical outcomes for neoadjuvant nivolumab in resectable NSCLC compare favorably with historical outcomes. MPR and PD-L1 positivity trended toward improved RFS, though definitive conclusions are limited by cohort size.

Recurrence per PDL1 and MPR

Supplementary Figure 1

Correlative assays performed on each sample

Purpose:Neoadjuvant PD-1 blockade is a promising treatment for resectable non–small cell lung cancer (NSCLC), yet immunologic mechanisms contributing to tumor regression and biomarkers of response are unknown. Using paired tumor/blood samples from a phase II clinical trial (NCT02259621), we explored whether the peripheral T-cell clonotypic dynamics can serve as a biomarker for response to neoadjuvant PD-1 blockade.Experimental Design:T-cell receptor (TCR) sequencing was performed on serial peripheral blood, tumor, and normal lung samples from resectable NSCLC patients treated with neoadjuvant PD-1 blockade. We explored the temporal dynamics of the T-cell repertoire in the peripheral and tumoral compartments in response to neoadjuvant PD-1 blockade by using the TCR as a molecular barcode.Results:Higher intratumoral TCR clonality was associated with reduced percent residual tumor at the time of surgery, and the TCR repertoire of tumors with major pathologic response (MPR; Conclusions:Our study suggests that exchange of T-cell clones between tumor and blood represents a key correlate of pathologic response to neoadjuvant immunotherapy and shows that the periphery may be a previously underappreciated originating compartment for effective antitumor immunity.See related commentary by Henick, p. 1205

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Supplementary table 1 and Supplementary figure legends.

Purpose:Despite the expansion of immune checkpoint inhibitor (ICI) indications, the relationship between ICI dose and toxicity or response is not well established. To understand this correlation, we performed a meta-analysis of ICI trials that used dose escalation.Experimental Design:We searched PubMed and abstracts presented at (inter)national meetings for trials using FDA-approved ICIs. The reported rates of grade 3–5 adverse events (G3–5 AE), immune-related adverse events (irAE), and response were correlated with doses within each ICI using marginal exact generalized linear models.Results:A total of 74 trials (7,469 patients) published between January 2010 and January 2017 were included. For ipilimumab, the incidence of G3–5 AEs was 34% with a significant 27% reduced risk in lower doses (P = 0.002). However, no relationship was observed between dose and irAEs or response. For nivolumab, the incidence of G3–5 AEs was 20.1% which was lower in non–small cell lung cancer (NSCLC) compared with renal cell carcinoma (RCC) or melanoma (P ≤ 0.05) with no dose-toxicity relationship. In melanoma and NSCLC, a dose–response association was observed, which was not observed in RCC. For pembrolizumab, the incidence of G3–5 AEs was 13.3%, which was lower in melanoma compared with NSCLC (P = 0.03) with no dose-toxicity relationship. In melanoma, lower dose levels correlated with decreased odds of response (P = 0.01), a relationship that was not observed in NSCLC.Conclusions:Our analysis shows a lack of consistent dose-toxicity or dose–response correlation with ICIs. Therefore, dose escalation is not an appropriate design to conduct ICI studies. Here we present an innovative trial design for immune-modulating agents.

Human gut microbial species found to associate with clinical responses to immune checkpoint inhibitors (ICIs) are often tested in mice using fecal microbiota transfer (FMT), wherein tumor responses in recipient mice may recapitulate human responses to ICI treatment. However, many FMT studies have reported only limited methodological description, details of murine cohorts, and statistical methods. To investigate the reproducibility and robustness of gut microbial species that impact ICI responses, we performed human to germ-free mouse FMT using fecal samples from patients with non-small cell lung cancer who had a pathological response or nonresponse after neoadjuvant ICI treatment. R-FMT mice yielded greater anti-tumor responses in combination with anti-PD-L1 treatment compared to NR-FMT, although the magnitude varied depending on mouse cell line, sex, and individual experiment. Detailed investigation of post-FMT mouse microbiota using 16S rRNA amplicon sequencing, with models to classify and correct for biological variables, revealed a shared presence of the most highly abundant taxa between the human inocula and mice, though low abundance human taxa colonized mice more variably after FMT. Multiple Clostridium species also correlated with tumor outcome in individual anti-PD-L1-treated R-FMT mice. RNAseq analysis revealed differential expression of T and NK cell-related pathways in responding tumors, irrespective of FMT source, with enrichment of these cell types confirmed by immunohistochemistry. This study identifies several human gut microbial species that may play a role in clinical responses to ICIs and suggests attention to biological variables is needed to improve reproducibility and limit variability across experimental murine cohorts.

BackgroundDespite treatment advancements with immunotherapy, our understanding of response relies on tissue-based, static tumor features such as tumor mutation burden (TMB) and programmed death-ligand 1 (PD-L1) expression. These approaches are limited in capturing the plasticity of tumor–immune system interactions under selective pressure of immune checkpoint blockade and predicting therapeutic response and long-term outcomes. Here, we investigate the relationship between serial assessment of peripheral blood cell counts and tumor burden dynamics in the context of an evolving tumor ecosystem during immune checkpoint blockade.MethodsUsing machine learning, we integrated dynamics in peripheral blood immune cell subsets, including neutrophil-lymphocyte ratio (NLR), from 239 patients with metastatic non-small cell lung cancer (NSCLC) and predicted clinical outcome with immune checkpoint blockade. We then sought to interpret NLR dynamics in the context of transcriptomic and T cell repertoire trajectories for 26 patients with early stage NSCLC who received neoadjuvant immune checkpoint blockade. We further determined the relationship between NLR dynamics, pathologic response and circulating tumor DNA (ctDNA) clearance.ResultsIntegrated dynamics of peripheral blood cell counts, predominantly NLR dynamics and changes in eosinophil levels, predicted clinical outcome, outperforming both TMB and PD-L1 expression. As early changes in NLR were a key predictor of response, we linked NLR dynamics with serial RNA sequencing deconvolution and T cell receptor sequencing to investigate differential tumor microenvironment reshaping during therapy for patients with reduction in peripheral NLR. Reductions in NLR were associated with induction of interferon-γ responses driving the expression of antigen presentation and proinflammatory gene sets coupled with reshaping of the intratumoral T cell repertoire. In addition, NLR dynamics reflected tumor regression assessed by pathological responses and complemented ctDNA kinetics in predicting long-term outcome. Elevated peripheral eosinophil levels during immune checkpoint blockade were correlated with therapeutic response in both metastatic and early stage cohorts.ConclusionsOur findings suggest that early dynamics in peripheral blood immune cell subsets reflect changes in the tumor microenvironment and capture antitumor immune responses, ultimately reflecting clinical outcomes with immune checkpoint blockade.

Purpose:Neoadjuvant PD-1 blockade is a promising treatment for resectable non–small cell lung cancer (NSCLC), yet immunologic mechanisms contributing to tumor regression and biomarkers of response are unknown. Using paired tumor/blood samples from a phase II clinical trial (NCT02259621), we explored whether the peripheral T-cell clonotypic dynamics can serve as a biomarker for response to neoadjuvant PD-1 blockade.Experimental Design:T-cell receptor (TCR) sequencing was performed on serial peripheral blood, tumor, and normal lung samples from resectable NSCLC patients treated with neoadjuvant PD-1 blockade. We explored the temporal dynamics of the T-cell repertoire in the peripheral and tumoral compartments in response to neoadjuvant PD-1 blockade by using the TCR as a molecular barcode.Results:Higher intratumoral TCR clonality was associated with reduced percent residual tumor at the time of surgery, and the TCR repertoire of tumors with major pathologic response (MPR; Conclusions:Our study suggests that exchange of T-cell clones between tumor and blood represents a key correlate of pathologic response to neoadjuvant immunotherapy and shows that the periphery may be a previously underappreciated originating compartment for effective antitumor immunity.See related commentary by Henick, p. 1205

Despite progress in immunotherapy, identifying patients that respond has remained a challenge. Through analysis of whole-exome and targeted sequence data from 5,449 tumors, we found a significant correlation between tumor mutation burden (TMB) and tumor purity, suggesting that low tumor purity tumors are likely to have inaccurate TMB estimates. We developed a new method to estimate a corrected TMB (cTMB) that was adjusted for tumor purity and more accurately predicted outcome to immune checkpoint blockade (ICB). To identify improved predictive markers together with cTMB, we performed whole-exome sequencing for 104 lung tumors treated with ICB. Through comprehensive analyses of sequence and structural alterations, we discovered a significant enrichment in activating mutations in receptor tyrosine kinase (RTK) genes in nonresponding tumors in three immunotherapy treated cohorts. An integrated multivariable model incorporating cTMB, RTK mutations, smoking-related mutational signature and human leukocyte antigen status provided an improved predictor of response to immunotherapy that was independently validated.

ImportanceAlthough cancer-related mortality continues to decline, lung cancer remains the No. 1 cause of cancer deaths in the US. Almost half of the patients with non–small cell lung cancer (NSCLC) are diagnosed with early-stage, local or regional disease and are at high risk of recurrence within 5 years of diagnosis.ObservationsImmune checkpoint inhibitors (ICIs) have improved outcomes for patients with metastatic NSCLC and have recently been tested in multiple clinical trials to determine their efficacy in the neoadjuvant or adjuvant setting for patients with local or regional disease. The landscape for perioperative ICIs in lung cancer is evolving rapidly, with recently reported and soon to mature clinical trials; however, the recent data highlight the potential of ICIs to increase response rates and decrease rates of relapse in early stages of lung cancer. Concurrently, novel applications of cell-free DNA may guide perioperative management strategies.Conclusions and RelevanceThis article reviews the various approaches of incorporating perioperative use of immunotherapeutic agents for the treatment of early stages of NSCLC.

300 Background: Immune checkpoint inhibitors (ICIs) have revolutionized the care of patients (pts) with cancer. However, median time to response is 2-6 months and many pts derive no benefit from ICIs. Pts are often admitted to the hospital with complications of advanced disease or its treatment, and many have prognoses limited to months. Several recent studies have demonstrated a limited benefit of anticancer therapy at end of life. ICIs are also associated with significant financial toxicity for both pts and the health care system. The role of ICI therapy in the inpatient (IP) setting is unclear. To begin to address this gap in knowledge, we conducted the Inpatient Immunotherapy Outcomes Study (IIOS) to describe characteristics and outcomes of pts who received IP ICIs. Methods: IIOS is a multicenter, retrospective study of pts treated with PD-(L)1 and CTLA-4 inhibitors during IP hospitalization between 2012-2021 at 4 large academic institutions: Mount Sinai Hospital, Yale-New Haven Hospital, University of Pennsylvania, and Georgetown University Hospital. Manual data collection was performed using each institution’s EMR and was approved by each institution’s IRB. Descriptive statistics were used to characterize the population and demonstrate pt outcomes. Results: A total of 159 pts received IPI ICI. Median age was 61 years. 54.7% of pts were white and 17.6% were Black; 12.6% were Hispanic. Thoracic/head and neck malignancies were most common (26.4%), followed by gastrointestinal (19.5%) and hematologic malignancies (17.6%). Most pts (73%) initiated ICIs in the IP setting while 27% continued an outpatient ICI regimen. 129 pts (81.1%) had stage IV solid malignancies at the time of ICI initiation in any setting; median prior lines of systemic therapy was 1 (range, 0-11). The most commonly administered IP ICI was pembrolizumab (49.1%) followed by nivolumab (34.0%), with ICIs administered with non-curative intent in 91.8% of pts. In 44.7% of pts, the ICI given did not have an FDA approval for that cancer type and stage at the time of administration. PD-L1 expression was available on tumors from 60 pts, 32 (53.3%) of whom had expression of 50% or higher. 112 pts (70.4%) had no documented clinical or imaging-based response to ICI therapy. Discharge disposition included home (47.2%), IP death (27%), rehabilitation centers (15.1%), and hospice (10.1%). Median days between first IP ICI dose and death was 47 (95% CI, 33-68). Conclusions: This is the largest multi-institutional effort to understand pt outcomes following IP ICI administration. Preliminary data, as outlined above, is concerning for poor clinical outcomes which should give clinicians pause when considering IP ICI use. Further analysis is ongoing to determine predictors of overall survival and discharge to home.

While both targeted therapy and immunotherapy-based strategies have emerged as frontline standard-of-care for patients with advanced lung cancer, acquired resistance and disease progression remain inevitable in most cases. Chemotherapy is a common salvage option in this scenario, but is limited by a relatively narrow therapeutic index. The emergence of antibody-drug conjugates (ADCs) offer an appealing alternative. ADCs couple the specificity of a monoclonal antibody with the cytotoxic effects of chemotherapy to facilitate the targeted delivery of cytotoxic payloads directly to cancer cells. Here, we review the general structure and function of ADCs, followed by a discussion of emerging ADCs in lung cancer and the future applications of this increasingly relevant class of novel agents.

PURPOSE: Immune checkpoint inhibitors (ICIs) cause immune-related adverse events (irAEs). The proportion of patients who are hospitalized for irAEs and their spectrum, management, and outcomes are not well described. METHODS: We report the proportion of hospitalized patients in an academic center who were treated with ICIs from May to December 2017. Patient characteristics, toxicities, management, and outcomes for confirmed irAE admissions are reported. Associations between patient features and irAE hospitalizations are examined. RESULTS: Twenty-three percent (n = 100) of 443 patients who were admitted to an academic oncology center over 6 months had ever received ICIs. Of these patients, 41% were admitted for suspected irAEs and 23% were confirmed irAEs. IrAEs accounted for 5% of all oncology hospitalizations (n = 23). Ninety-one percent of patients with confirmed irAEs prompted a medicine subspecialist consultation, most commonly gastroenterology (22%). Fifteen patients (65%) had their irAEs improve/resolve, seven (30%) had worsening irAEs, and three (13%) died of their irAEs. The majority of patients (n = 20; 87%) discontinued ICIs after discharge. Among ICI-treated patients who required admission, an increased likelihood of irAE-related hospitalization was associated with patient age older than 65 years (odds ratio, 5.4; 95% CI, 1.6 to 17.8) and receipt of combination immunotherapy (OR, 6.8; 95% CI, 2.0 to 23.2). CONCLUSION: A notable proportion of ICI-treated patients are hospitalized for irAEs, and these patients have a high demand for multidisciplinary management. Older age and combination ICI treatment were associated with an increased risk of irAE-related hospitalization. Whereas these data are from an academic center and include patients in clinical trials, with expanding use of ICIs, these data have important implications for inpatient service planning and risk stratification.

Early-stage non–small cell lung cancer is a potentially curable disease, but with relapse rates exceeding 50% with standard treatments, this is a patient population in critical need of therapy innovation. Immunotherapy with immune checkpoint blockade has revolutionized the treatment strategy for advanced lung cancer. However, the role of this therapy in earlier-stage disease is largely unknown. The study of immunotherapy in earlier-stage disease has many advantages, including assessment of pathologic response and incorporation of translational scientific analyses to evaluate antitumor immune responses. Multiple clinical trials are currently under way, with promising early results.

TPS9147 Background: KRAS is mutated (mt) in 25% of NSCLC adenocarcinoma, with KRAS G12V and G12C mt occurring in ̃7% and ̃13% of patients (pts), respectively. Whereas G12C inhibitors have demonstrated promising activity in pts with KRAS G12C NSCLC, KRAS G12V NSCLC remains an unmet need. BRAF mt occurs in ̃4% of NSCLC with roughly equal split between BRAF V600E and non-V600E. VS-6766 is a small molecule RAF/MEK clamp that inhibits BRAF, CRAF and MEK, enabling VS-6766 to block MEK signaling without compensatory activation of MEK observed with MEK-only inhibitors. VS-6766 potently inhibits proliferation of KRAS and BRAF mt cell lines. Focal adhesion kinase (FAK) activation is a putative resistance mechanism to RAF and MEK inhibition, and defactinib, a small molecule FAKi, has shown synergistic anti-tumor activity with VS-6766 in KRAS mt NSCLC models. In a KRAS G12V mt NSCLC mouse model, which was shown to be especially dependent on CRAF, VS-6766 induced strong tumor regressions both as monotherapy and in combination with FAKi (Coma AACR 2021). Clinically, VS-6766 monotherapy has shown responses in KRAS mt NSCLC including pts with KRAS G12V and in pts with BRAF V600E solid tumors (Guo 2020; Martinez-Garcia 2012). The combination of VS-6766 + defactinib is currently being evaluated in the Investigator Sponsored FRAME study. In an updated analysis of response in 20 pts with KRAS mt NSCLC, there were 2 confirmed PRs, 1 unconfirmed PR and 10 SDs (ORR = 15%; DCR = 65%) with 7/20 pts remaining on treatment for ≥24 weeks. The 2 pts with KRAS G12V NSCLC both had confirmed PRs (ORR = 100%). This combination regimen exhibited a manageable safety profile with no NSCLC pts discontinuing for adverse events (Krebs AACR 2021). Methods: This is an international phase 2, adaptive, multicenter, randomized, open label study designed to evaluate the efficacy and safety of VS-6766 vs. VS-6766 + defactinib in pts with recurrent KRAS or BRAF mt NSCLC (NCT04620330). Part A will determine the optimal regimen, either VS-6766 monotherapy or VS-6766 + defactinib based on pts with KRAS G12V. Part A will consist of 5 NSCLC arms: Arm 1 VS-6766 monotherapy in KRAS G12V, Arm 2 VS-6766 + defactinib in KRAS G12V, Arm 3 the combination in KRAS non-G12V, Arm 4 the combination in BRAF V600E and Arm 5 the combination in BRAF non-V600E. Part B will determine the efficacy of the optimal regimen identified in Part A. Pts must have histologic or cytologic evidence of NSCLC, measurable disease according to RECIST V1.1, known KRAS or BRAF mt and at least 1 prior systemic therapy (appropriate therapy for activating mutation and/or platinum-based therapy). Part A will enroll 102 pts Arms 1 and 2 (KRAS G12V), and Arms 4 and 5 (BRAF V600E and non-V600E) are currently open. Arm 3 (KRAS non-G12V) enrollment is completed. The total number of pts in Part B will be determined by results from Part A. Clinical trial information: NCT04620330.

8537 Background: Neoadjuvant (neoadj) immune checkpoint blockade (ICB) with anti-PD-1 therapy has shown increasing promise for early stage NSCLC, with long-term clinical outcomes still maturing. Our group reported the first phase I/II trial of neoadj nivolumab (nivo) in resectable NSCLC, finding therapy to be safe and feasible. We now present final clinical results from this cohort, representing the longest follow up data for neoadj anti-PD-1 to date. Methods: Two doses of neoadj nivo (3 mg/kg) were given prior to resection in 21 patients (pts) with resectable NSCLC. 5-year (yr) follow-up data, including recurrence-free survival (RFS), overall survival (OS) and association with pathologic response were tabulated. Event time distributions were estimated with the Kaplan-Meier method. All p-values are two-sided with 0.05 significance level. Results: At a median follow up of 63 months, 3-, 4- and 5-yr survival rates were 85, 80, and 80% respectively. RFS rates at 3-, 4- and 5-yrs were 65, 60, and 60% respectively. As previously reported, major pathologic response (MPR: ≤10% viable tumor) was 45%, and pathologic complete response (pCR) rate was 10%. The hazard ratio (HR) for pathologic down-staging was in the direction of improved RFS, without meeting statistical significance (HR 0.36, 95% CI 0.07-1.75, p = 0.2). RFS HR estimates for MPR and an alternative pathologic cut-off of less than 50% residual tumor (RT), were 0.61, (95% CI 0.15-2.44, p = 0.48) and 0.36, (95% CI 0.09-1.51, p = 0.16) respectively. The direction of the effect of pre-treatment PD-L1 positivity (≥1%) was to improve RFS (HR 0.36, 95% CI 0.07-1.85, p = 0.22). At 5-yr follow up, 8 of 9 (89%) pts with MPR were alive and no cancer deaths have occurred. Amongst pts with MPR, 1/9 pts had a cancer recurrence in the mediastinum treated successfully with definitive chemoradiotherapy. Both pts with pCR are alive and without recurrence. Patterns of all recurrences in this cohort are summarized in table 1. No long-term immune-related adverse events have occurred other than one G3 dermatologic event. Conclusions: The 5-yr clinical outcomes for neoadj nivo in resectable NSCLC compare favorably to historical trends. MPR trended toward improved RFS, while definitive conclusions are limited by our cohort size and overall low recurrence rate. Thresholds of %RT beyond pCR and MPR in this setting should be explored in larger prospective studies. PD-L1 expression may play a role in predicting long-term response, but larger prospective studies are needed. Clinical trial information: NCT02259621. [Table: see text]

Osimertinib, a third-generation EGFR tyrosine kinase inhibitor, is the preferred frontline therapy for EGFR-mutant advanced NSCLC. However, despite its high initial response rates, multiple EGFR-independent mechanisms of resistance have been reported in patients receiving osimertinib. One such mechanism is the emergence of acquired, targetable oncogenic fusion events. It has been documented in other case reports that combination therapies can be efficacious in these scenarios. In our case report, we present a patient with EGFR-mutant advanced NSCLC who developed an acquired EML4-ALK rearrangement mediating resistance to osimertinib, which was overcome by using a combination of osimertinib with the ALK tyrosine kinase inhibitor alectinib.

PD-1 blockade unleashes CD8 T cells1, including those specific for mutation-associated neoantigens (MANA), but factors in the tumour microenvironment can inhibit these T cell responses. Single-cell transcriptomics have revealed global T cell dysfunction programs in tumour-infiltrating lymphocytes (TIL). However, the majority of TIL do not recognize tumour antigens2, and little is known about transcriptional programs of MANA-specific TIL. Here, we identify MANA-specific T cell clones using the MANA functional expansion of specific T cells assay3 in neoadjuvant anti-PD-1-treated non-small cell lung cancers (NSCLC). We use their T cell receptors as a ‘barcode’ to track and analyse their transcriptional programs in the tumour microenvironment using coupled single-cell RNA sequencing and T cell receptor sequencing. We find both MANA- and virus-specific clones in TIL, regardless of response, and MANA-, influenza- and Epstein–Barr virus-specific TIL each have unique transcriptional programs. Despite exposure to cognate antigen, MANA-specific TIL express an incompletely activated cytolytic program. MANA-specific CD8 T cells have hallmark transcriptional programs of tissue-resident memory (TRM) cells, but low levels of interleukin-7 receptor (IL-7R) and are functionally less responsive to interleukin-7 (IL-7) compared with influenza-specific TRM cells. Compared with those from responding tumours, MANA-specific clones from non-responding tumours express T cell receptors with markedly lower ligand-dependent signalling, are largely confined to HOBIThigh TRM subsets, and coordinately upregulate checkpoints, killer inhibitory receptors and inhibitors of T cell activation. These findings provide important insights for overcoming resistance to PD-1 blockade., Single-cell RNA sequencing and T cell receptor sequencing are combined to identify transcriptional programs specific to mutation-associated neoantigen-specific T cells in non-small cell lung cancers treated with anti-PD-1, providing insights into resistance to PD-1 blockade.

Key Points Question Has inclusion of people living with HIV in anti–programmed death 1 and anti–programmed death ligand 1 (anti–PD1/PDL1) immunotherapy trials changed during ongoing Cancer Therapy Evaluation Program advocacy efforts by the National Cancer Institute? Findings In this quality improvement analysis of 87 anti–PD1/PDL1 trials approved by the Cancer Therapy Evaluation Program from January 2014 to May 2019, the proportion of studies including people living with HIV increased from 16% of letters of intent to 70% of approved protocols. Inclusion of people living with HIV on submitted letters of intent increased over time. Meaning This study’s findings suggest that the increasing inclusion rates of people living with HIV in anti–PD1/PDL1 clinical trials are encouraging and that advocacy for these and other underrepresented populations should continue., This quality improvement study evaluates trends in the inclusion of people living with HIV in anti–programmed death 1 and anti–programmed death ligand 1 (anti–PD1/PDL1) clinical trials concurrent with ongoing Cancer Therapy Evaluation Program efforts by the National Cancer Institute to promote inclusion of this patient population., Importance Anti–programmed death 1 and anti–programmed death ligand 1 (anti–PD1/PDL1) immune checkpoint blockade (ICB) constitutes the therapeutic backbone for multiple malignant neoplasms. People living with HIV (PLWH) have routinely been excluded from ICB clinical trials, thus inhibiting broad implementation of ICB to PLWH with cancer. Objective To evaluate trends in the inclusion of PLWH in ICB cancer clinical trials that have occurred in association with ongoing efforts by the Cancer Therapy Evaluation Program (CTEP), National Cancer Institute, to promote inclusion of PLWH. Design, Setting, and Participants This quality improvement study of ICB letters of intent (LOIs) included anti–PD1/PDL1 agents (nivolumab, pembrolizumab, atezolizumab, and durvalumab) submitted to CTEP that proceeded to approved protocols between January 2014 to May 2019. The setting was ICB clinical trial development and inclusion of underrepresented populations, specifically PLWH. All 97 submitted cancer clinical trial LOIs that included the aforementioned ICB agents were eligible for inclusion. Ten proposals were excluded, of which 3 were designed specifically for PLWH and 7 were LOIs that did not advance to approved protocols within the study period. Statistical analysis was performed from April to September 2020. Exposures CTEP advocacy included the requirement for justification of exclusion of PLWH and formal discussion of inclusion criteria during conference calls between CTEP and trial investigators. Main Outcomes and Measures The frequency of inclusion of PLWH in initially submitted LOIs was compared with final approved protocols using descriptive statistics. The probability of inclusion of PLWH in submitted LOIs and approved protocols over time was assessed using logistic regression. Results Eighty-seven studies were included, of which 68 (78%) were pilot, phase 1, phase 1/2, or phase 2 studies and 19 (22%) were phase 2/3 or phase 3 studies. Thirty-nine studies (45%) included nivolumab, 23 (26%) included pembrolizumab, 19 (22%) included atezolizumab, and 6 (7%) included durvalumab. At initial LOI stage, 14 of 87 (16%) included PLWH. Following CTEP advocacy efforts, 61 of 87 protocols (70%) included PLWH. Of 36 LOIs to initially exclude PLWH, 24 (67%) included PLWH in final protocols. Among the 25 protocols to exclude PLWH, 21 (84%) were earlier phase studies (pilot to phase 2) and 4 (16%) were later phase studies (phase 2/3 to phase 3). Only 13 of 25 protocols (52%) provided justification for exclusion of PLWH, with safety being the most frequently cited concern (9 of 13 studies). The inclusion of PLWH on submitted LOIs increased over time (odds ratio, 3.38; 95% CI, 1.14-3.91), whereas inclusion on final protocols did not increase over time (odds ratio, 1.80; 95% CI, 0.81-1.59). Conclusions and Relevance This study identified encouraging trends in the inclusion of PLWH in anti–PD1/PDL1 cancer trials that occurred in the period following the initiation of CTEP advocacy. Work is needed to examine what impact this will have on enrollment of PLWH in such trials. Similar advocacy may help to promote inclusion of other underrepresented populations in cancer clinical trials, including those with organ dysfunction and chronic infections.

Therapeutic advancement for mesothelioma has been stagnant, with minimal treatment innovation in the past decade. Recently, however, immune checkpoint blockade (ICB) targeting the programmed death 1 and cytotoxic T-lymphocyte-associated antigen 4 pathways has revolutionized the treatment of multiple malignancies and shown promise in mesothelioma, with multiple agents now recommended in the salvage setting for advanced disease progressive on platinum-based chemotherapy. Studies of frontline chemoimmunotherapy and ICB combinations have also been encouraging, and both are likely to become integrated into the frontline treatment strategy for mesothelioma in the coming years. Other novel immunotherapy strategies, including chimeric antigen receptor T-cell therapy, are being investigated in mesothelioma. Although early studies have demonstrated the safety of multiple agents, further trials powered for efficacy are needed. In addition, enrolling patients in window-of-opportunity trials of ICB in resectable mesothelioma and biomarker-focused correlative studies will be critical to furthering the mechanistic understanding of ICB in mesothelioma, which in turn will help to uncover biomarkers of response and resistance in these patients.

BackgroundWe conducted the first trial of neoadjuvant PD-1 blockade in resectable non-small cell lung cancer (NSCLC), finding nivolumab monotherapy to be safe and feasible with an encouraging rate of pathologic response. Building on these results, and promising data for nivolumab plus ipilimumab (anti-CTLA-4) in advanced NSCLC, we expanded our study to include an arm investigating neoadjuvant nivolumab plus ipilimumab.MethodsPatients with resectable stage IB (≥4 cm)–IIIA (American Joint Committee on Cancer Tumor Node Metastases seventh edition), histologically confirmed, treatment-naïve NSCLC received nivolumab 3 mg/kg intravenously plus ipilimumab 1 mg/kg intravenously 6 weeks prior to planned resection. Nivolumab 3 mg/kg was given again approximately 4 and 2 weeks preoperatively. Primary endpoints were safety and feasibility with a planned enrollment of 15 patients. Pathologic response was a key secondary endpoint.ResultsWhile the treatment regimen was feasible per protocol, due to toxicity, the study arm was terminated early by investigator consensus after 9 of 15 patients were enrolled. All patients received every scheduled dose of therapy and were fit for planned surgery; however, 6 of 9 (67%) experienced treatment-related adverse events (TRAEs) and 3 (33%) experienced grade ≥3 TRAEs. Three of 9 patients (33%) had biopsy-confirmed tumor progression precluding definitive surgery. Of the 6 patients who underwent resection, 3 are alive and disease-free, 2 experienced recurrence and are actively receiving systemic treatment, and one died postoperatively due to acute respiratory distress syndrome. Two patients who underwent resection had tumor pathologic complete responses (pCRs) and continue to remain disease-free over 24 months since surgery. Pathologic response correlated with pre-treatment tumor PD-L1 expression, but not tumor mutation burden. Tumor KRAS/STK11 co-mutations were identified in 5 of 9 patients (59%), of whom two with disease progression precluding surgery had tumor KRAS/STK11/KEAP1 co-mutations.ConclusionsThough treatment was feasible, due to toxicity the study arm was terminated early by investigator consensus. In light of this, and while the long-term disease-free status of patients who achieved pCR is encouraging, further investigation of neoadjuvant nivolumab plus ipilimumab in patients with resectable NSCLC requires the identification of predictive biomarkers that enrich for response.

Purpose: Despite the expansion of immune checkpoint inhibitor (ICI) indications, the relationship between ICI dose and toxicity or response is not well established. To understand this correlation, we performed a meta-analysis of ICI trials that used dose escalation. Experimental Design: We searched PubMed and abstracts presented at (inter)national meetings for trials using FDA-approved ICIs. The reported rates of grade 3–5 adverse events (G3–5 AE), immune-related adverse events (irAE), and response were correlated with doses within each ICI using marginal exact generalized linear models. Results: A total of 74 trials (7,469 patients) published between January 2010 and January 2017 were included. For ipilimumab, the incidence of G3–5 AEs was 34% with a significant 27% reduced risk in lower doses (P = 0.002). However, no relationship was observed between dose and irAEs or response. For nivolumab, the incidence of G3–5 AEs was 20.1% which was lower in non–small cell lung cancer (NSCLC) compared with renal cell carcinoma (RCC) or melanoma (P ≤ 0.05) with no dose-toxicity relationship. In melanoma and NSCLC, a dose–response association was observed, which was not observed in RCC. For pembrolizumab, the incidence of G3–5 AEs was 13.3%, which was lower in melanoma compared with NSCLC (P = 0.03) with no dose-toxicity relationship. In melanoma, lower dose levels correlated with decreased odds of response (P = 0.01), a relationship that was not observed in NSCLC. Conclusions: Our analysis shows a lack of consistent dose-toxicity or dose–response correlation with ICIs. Therefore, dose escalation is not an appropriate design to conduct ICI studies. Here we present an innovative trial design for immune-modulating agents.

Checkpoint inhibitor pneumonitis (CIP) is a toxicity of immune checkpoint blockade (ICB) that can be highly morbid and at times fatal. Here, we review the proposed biologic mechanisms of CIP, epidemiology and risk factors for CIP development, diagnostic work-up and management strategies for CIP, and future directions of CIP research. CIP incidence appears to be greater in real-world populations and may continue to rise as FDA approvals for ICB continue to expand to multiple malignancies. Multiple retrospective studies and case series have identified potential risk factors for CIP. Several society guidelines have helped to unify the classification of CIP severity and standardize treatment approaches but significant gaps remain, including formal validated diagnostic criteria for CIP. While significant strides have been made in enhancing the knowledge and management of CIP, ongoing research is needed to continue to advance our understanding of the biologic underpinnings of CIP, as well as optimize diagnostic and management strategies for this potentially devastating toxicity.

The global COVID-19 pandemic has disrupted healthcare delivery, particularly for patients with advanced lung cancer. While certain aspects of care can be safely omitted or delayed, systemic therapy plays an important role in survival and quality of life for patients with advanced lung cancer; limiting access to systemic therapy will compromise cancer-related outcomes. This can be at odds with strategies to mitigate risk of COVID-19 exposure, which include reducing hospital and clinic visits. One important strategy is implementation of oral cancer therapies. Many standard regimens require intravenous infusions but there are specific circumstances where an oral agent could be an acceptable alternative. Integrating oral therapeutics can permit patients to receive effective systemic treatment without the exposure risks associated with frequent infusions. Here, we review currently available oral cytotoxic agents with a potential role in the treatment of lung cancer.

BackgroundImmune checkpoint inhibitors (ICI) are standard treatment for stage III/IV non-small cell lung cancer (NSCLC). ICIs may cause immune-related adverse events (irAEs) often requiring corticosteroids or other immunosuppressive therapy and are associated with increased risk of opportunistic infections.1 2 The burden of infectious complications in NSCLC patients (pts) treated with ICIs is poorly described.MethodsWe retrospectively reviewed NSCLC pts treated with ICIs between 2016–2020 at a large tertiary academic center. An infectious complication related to ICIs was defined as a pathogen-confirmed or clinically diagnosed infection requiring antimicrobials during or within 3 months of ICI discontinuation. High-grade infections were defined as those requiring IV antibiotics (grade 3), life-threatening or requiring ICU stay (grade 4), or resulting in death (grade 5). irAEs were defined by the treating provider and treated according to standard guidelines. Patient demographics, treatment data, cancer outcomes, infectious complications, and irAE details were annotated in an IRB-approved database. An AE treated as both an infection and/or irAE with antibiotics and immunosuppression was coded as a concomitant irAE/infection event. The association between patient features and infectious complications was examined using logistic regression. Treatment and disease characteristics for concomitant irAE with infection were also described.Results302 ICI-treated NSCLC pts were included. 211 pts received PD-1 monotherapy and 91 received PD-1 therapy with CTLA-4 therapy, chemotherapy, or other investigational therapy. The majority (175/302, 57.9%) had a documented infection (bacterial=138, viral=17, fungal=19, mycobacterial=1) during or within 3 months of ICI discontinuation. Grade ≥3 infections occurred in 33.4% of pts (101/302). Pulmonary infections were most common (35.4%), followed by gastrointestinal, urinary, and skin (ConclusionsIn this retrospective study of NSCLC pts treated with ICIs, the majority experienced infections during or within 3 months of ICI discontinuation. The most common infections were bacterial pulmonary in origin. Concomitant irAE/infection was associated with trend toward higher odds of hospitalization.ReferencesHamashima R, Uchino J, Morimoto Y, et al. Association of immune checkpoint inhibitors with respiratory infections: a review. Cancer Treatment Reviews 2020;90:102109. doi:10.1016/j.ctrv.2020.102109Lu M, Zhang L, Li Y, et al. Recommendation for the diagnosis and management of immune checkpoint inhibitor related infections. Thorac Cancer 2020;11(3):805–809. doi:10.1111/1759-7714.13313Ethics ApprovalThis retrospective chart review study has obtained ethics approval from the Institutional Review Board at the Johns Hopkins School of Medicine (number: IRB00129424).

Introduction Checkpoint inhibitor pneumonitis (CIP) is a serious toxicity of anti–programmed death-(ligand) 1 immunotherapy. Whether pretreatment differences in pulmonary function exist in patients who develop CIP is unknown. We analyzed the pulmonary function tests (PFTs) of patients with NSCLC treated with immune checkpoint inhibitors (ICIs) to evaluate whether pretreatment lung function was associated with CIP development. Methods Patients were included if they completed greater than or equal to 1 PFT within 2 years preceding ICI initiation. CIP status (CIP+: developed CIP, CIP−: did not develop CIP) was determined clinically. Generalized estimating equation–based linear regression was used to evaluate the effects of time and CIP on lung function. Primary outcomes included the following: percent-predicted forced expiratory volume in 1 second (FEV1pp), percent-predicted forced vital capacity (FVCpp), and FEV1/FVC. Results A total of 43 patients (34 CIP−, 9 CIP+) with 79 PFTs (59 CIP−, 20 CIP+) were included. CIP+ patients had a 21.7% lower pretreatment FEV1pp compared with the CIP− group (95% confidence interval: −38.6 to −4.7). No statistically significant differences in FVCpp or FEV1/FVC were observed. The prevalence of obstructive lung disease was similar in both groups at 67% and 62% for the CIP+ and CIP− cohorts, as was the prevalence of current/former smoking at 100% and 93%, respectively. Conclusions Pretherapy differences in lung function were evident between patients who did and did not develop CIP, though the prevalence of obstructive lung disease was similar. Prospective studies are needed to validate these findings, inform potential risk factors for CIP, and investigate the effects of ICI treatment and CIP on pulmonary function in patients with NSCLC.

Background: Treatment-induced anti-tumor immune response may be reflected in peripheral blood leukocyte composition and shifts. The relative abundance of immune cell subsets captured by neutrophil-to-lymphocyte ratio (NLR) is a promising biomarker of response to immune checkpoint inhibition (ICI). However early dynamics and integration with circulating tumor DNA (ctDNA) kinetics during ICI have not been comprehensively studied. Methods: We evaluated the predictive role of early dynamic changes of peripheral immune cell subsets in 239 ICI treated metastatic non-small cell lung cancers (mNSCLC) and combined those with ctDNA dynamics in 18 early stage NSCLCs (esNSCLC) treated with neoadjuvant ICI. Blood cell counts were analyzed at baseline, 4 weeks on treatment, and at first radiographic follow up (mNSCLC) or preoperatively (esNSCLC). mNSCLC patients without progression at 6 months were considered to have durable clinical benefit (DCB). We employed eXtreme Gradient Boosting, a decision-tree based machine learning algorithm, to integrate baseline values and early changes in immune cell subsets. To reduce modeling overfitting, we trained an ensemble of models, incorporating 10-fold cross-validation that included feature selection (training n=171) and tested the model in an unseen independent set (n=68). For esNSCLCs, major pathologic response (MPR; ≤10% residual tumor; RT) was determined. We performed Targeted Error Correction next generation sequencing on 60 serial plasma and matched leukocyte DNA samples to assess ctDNA clonal dynamics. Changes in immune cell subsets were correlated with RT, MPR, progression-free (PFS) and overall survival (OS). Results: Our machine learning integrative model predicted DCB with an area under the ROC curve (AUC) of 0.96 for training, 0.72 for cross-validation testing and 0.74 for unseen testing datasets. Feature importance analysis revealed that NLR at 4 weeks, first radiographic follow up, and relative change in NLR from baseline were the strongest predictors of outcome together with relative eosinophil and lymphocyte count. Our model's performance was superior to TMB (AUC=0.52) or PD-L1 (AUC=0.54). For esNSCLCs, change in NLR at 4 weeks after ICI initiation was predictive of tumor regression (p=0.02), such that those with MPR showed significant decrease in NLR. This was also predictive of PFS (log rank p=0.004) and OS (log rank p=0.02). Furthermore, higher eosinophil count at 4 weeks was correlated with MPR (p=0.006) and decreased RT (p=0.006). Immune cell subset kinetics were concordant with ctDNA clearance in all but two patients and importantly NLR dynamics at 4 weeks were predictive of MPR even when ctDNA was undetectable. Conclusions: Early changes in peripheral immune cell subsets together with ctDNA are reflective of anti-tumor immune response during ICI and may more accurately predict ICI response than currently used biomarkers. Citation Format: Michael Hwang, Jenna Canzoniero, Samuel Rosner, Guangfan Zhang, Mara Lanis, Lamia Rhymee, Alexandria Curry, Gavin Pereira, Kristen Marrone, Joshua Reuss, Jarushka Naidoo, Christine Hann, Vincent Lam, Benjamin Levy, David Ettinger, Patrick Forde, Julie Brahmer, Victor Velculescu, Tanguy Seiwert, Valsamo Anagnostou. Early dynamics in peripheral blood immune cell subsets and ctDNA are predictive of outcome to immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 27.

Inflammation is essential for our innate and adaptive immunity, but chronic inflammation can also be detrimental, playing a role in tumor development and subversion of host immunity. A multitude of proteins and cytokines are involved in chronic inflammation; interleukin-1β, in particular, has been recognized as a critical pro-inflammatory cytokine that can trigger a cascade of inflammatory mediators, promoting angiogenesis, tumor invasiveness, and metastasis. The inhibition of interleukin-1β with the antibody canakinumab was recently highlighted in a large-scale trial studying the effects of the inflammatory modulating antibody in heart disease. In this study, a marked decrease in the incidence of lung cancer (a 67% relative risk reduction) was observed in a high-risk population. Although a number of preclinical studies have demonstrated that canakinumab inhibits interleukin-1β and reduces inflammation, the question remains whether these actions positively affect both cancer incidence and recurrence. This review will summarize the role of inflammation in cancer propagation and development, discuss the biological rationale for targeting interleukin-1β in lung cancer, advocate for further investigation of the anti-inflammatory antibody canakinumab as a new attractive mechanism for future lung cancer therapy, and discuss future and ongoing trials.

3091 Background: Gene fusions often represent critical therapeutic targets across cancer subtypes. Fusions within the ErbB family of receptor tyrosine kinases, including EGFR, ERBB2 ( HER2) and ERBB4 ( HER4), have been previously described and represent potentially actionable alterations. Here, we report the relative incidence and functional characterization of these rare genomic events. Methods: Tumor samples (n = 64,354; representing > 40 tumors types) submitted to Caris Life Sciences (Phoenix, AZ) were molecularly profiled by next-generation sequencing of DNA (NextSeq, 592-gene panel; or NovaSeq, whole exome) and RNA (whole transcriptome). Gene fusion partners, in/out-of-frame status, retention of ERBB kinase domain, and topology of fusion breakpoints were characterized for each ERBB fusion transcript detected. Fusion prevalence was further examined in public data sets (TCGA, MSK-IMPACT and AACR GENIE). Results: From the Caris database, a total of 64 EGFR fusion isoforms were detected in 59 tumors (incidence 0.09%); 83% were in-frame and 91% retained the EGFR kinase domain. 206 ERBB2 fusion isoforms were detected in 114 tumors (0.18%); 37% were in-frame and 34% retained the ERBB2 kinase domain. 131 ERBB4 fusion isoforms were detected in 108 tumors (0.17%); 62% were in-frame and 51% retained the kinase domain. All fusions were detected at low incidence across all tumor types. EGFR fusions were most common in high grade glioma (1.7%, n = 35), largely driven by recurrent EGFR-SEPT14 fusions (n = 20). ERBB2 fusions were most common in esophageal/gastroesophageal junction carcinoma (1.1%, n = 20), with recurrent fusion to PGAP3 observed in multiple tumor types (n = 37). ERBB4 fusions were most common in ovarian (0.7%, n = 40) and bladder (0.7%, n = 15) cancers, which often resulted from recurrent fusion with IKZF2 (n = 36). EGFR and ERBB2 fusions were generated predominantly (44-48%) from inversion events, while ERBB4 fusions arose more frequently and at similar rates (27-32%) from deletions, duplications, or translocations. Mining of public data sets corroborated the prevalence of ERBB gene fusions: the frequency of EGFR fusions was 0.63%, ERBB2 was 0.14% and ERBB4 was 0.04%. TP53 mutations frequently co-occurred with ERBB2 and ERBB4 fusions ( > 60% average across public data sets), with higher co-mutation rates ( > 70%) observed for samples in the Caris database. Conclusions: ERBB gene fusions are detectable at low frequency in various tumor types and may represent a unique genomic subset of cancer. Identification of novel ERBB gene fusions warrants further investigation to determine the potential pathogenicity and actionability of these fusions.

Immune-related (IR)-pneumonitis is a rare and potentially fatal toxicity of anti-PD(L)1 immunotherapy. Expert guidelines for the diagnosis and management of IR-pneumonitis include multidisciplinary input from medical oncology, pulmonary medicine, infectious disease, and radiology specialists. Severe acute respiratory syndrome coronavirus 2 is a recently recognized respiratory virus that is responsible for causing the COVID-19 global pandemic. Symptoms and imaging findings from IR-pneumonitis and COVID-19 pneumonia can be similar, and early COVID-19 viral testing may yield false negative results, complicating the diagnosis and management of both entities. Herein, we present a set of multidisciplinary consensus recommendations for the diagnosis and management of IR-pneumonitis in the setting of COVID-19 including: (1) isolation procedures, (2) recommended imaging and interpretation, (3) adaptations to invasive testing, (4) adaptations to the management of IR-pneumonitis, (5) immunosuppression for steroid-refractory IR-pneumonitis, and (6) management of suspected concurrent IR-pneumonitis and COVID-19 infection. There is an emerging need for the adaptation of expert guidelines for IR-pneumonitis in the setting of the global COVID-19 pandemic. We propose a multidisciplinary consensus on this topic, in this position paper.

TPS9078 Background: While the role of surgery in limited-stage (stage I-III) malignant pleural mesothelioma (MPM) is controversial, many centers have adopted an aggressive tri-modality approach incorporating (neo)adjuvant chemotherapy, surgical resection and radiotherapy. Despite this, most patients relapse and die from their disease. Immune checkpoint blockade (ICB) has shown promise in advanced MPM, but the mechanisms of response and resistance remain elusive. Improving the mechanistic understanding of ICB in MPM while concurrently optimizing the treatment strategy for limited-stage MPM are two urgent unmet needs. This multicenter multi-arm phase I/II study seeks to evaluate the safety and feasibility of neoadjuvant ICB in resectable MPM, incorporating novel genomic and immunologic analyses to deliver mechanistic insight into the biology of ICB in MPM. Methods: Patients with surgically resectable stage I-III treatment-naïve epithelioid or biphasic MPM receive neoadjuvant treatment with nivolumab every 2 weeks for 3 doses with or without 1 dose of ipilimumab (arm A: nivolumab monotherapy; arm B: nivolumab + ipilimumab). After macroscopic complete resection, patients receive optional investigator-choice adjuvant chemotherapy +/- radiation. Following this, patients will receive up to 1 year of adjuvant nivolumab. Feasibility and safety are co-primary endpoints of this study with feasibility defined by a delay in surgery of ≤24 days from the preplanned surgical date and safety defined by adverse events according to CTCAE v5.0. Bayesian-designed stopping rules have been implemented for feasibility and safety. Secondary endpoints include assessment of pathologic response and radiographic response using RECIST 1.1 for MPM. Correlative analyses will be performed on tissue specimens obtained pre- and post-ICB, as well as blood obtained pre, during, and post-ICB. Key correlates include multiplex immunofluorescence and longitudinal ctDNA assessment. Whole exome sequencing, T-cell receptor sequencing, and the MANAFEST functional neoantigen assay will be utilized to identify neoantigen-specific T-cell clonotypes and track these clonotypes temporally (during/post ICB) and spatially (across immune compartments). Single-cell RNA sequencing will be used to characterize the functionality of expanded T-cell clonotypes. Accrual to arm B will commence following complete accrual to arm A with a planned total enrollment of 30 patients. This study is open with 1 patient enrolled at the time of submission. Clinical trial information: NCT03918252.