Shifting Sociodemographic Characteristics of a Phase I Clinical Trial Population at an NCI-Designated Comprehensive Cancer Center in the Southeast

Racial and ethnic minority populations are consistently under-represented in oncology clinical trials despite comprising a disproportionate share of a cancer burden. Phase I oncology clinical trials pose a unique challenge and opportunity for minority inclusion. Here we compared the sociodemographic characteristics of patients participating in phase 1 clinical trials a National Cancer Institute ( NCI)-designated comprehensive center to all patients at the center, patients with new cancer diagnosis in metropolitan Atlanta and patients with new cancer diagnoses in the state of Georgia. From 2015 to 2020, 2325 patients (43.4% female, 56.6% male) consented to participate in a phase I trial. Grouped self-reported race distribution was 70.3% White, 26.2% Black, and 3.5% other. Of new patient registrations at Winship Cancer Institute (N = 107 497) (50% F, 50% M), grouped race distribution was 63.3% White, 32.0% Black, and 4.7% other. Patients with new cancer diagnoses in metro Atlanta from 2015 to 2016 (N = 31101) were 58.4% White, 37.2% Black, and 4.3% other. Race and sex distribution of phase I patients was significantly different than Winship patients (P < .001). Over time, percent of White patients decreased in both phase I and Winship groups (P = .009 and P < .001, respectively); percentage of females did not change in either group (P = .54 phase I, P = .063 Winship). Although phase I patients were more likely to be White, male, and privately ensured than the Winship cohort, from 2015 to 2020 the percentage of White patients in phase I trials and among all new patients treated at Winship decreased. The intent of characterizing existing disparities is to improve the representation of patients from racial and ethnic minority backgrounds in phase I clinical trials.

Tarlatamab for Patients with Previously Treated Small-Cell Lung Cancer

BACKGROUND

Tarlatamab, a bispecific T-cell engager immunotherapy targeting delta-like ligand 3 and CD3, showed promising antitumor activity in a phase 1 trial in patients with previously treated small-cell lung cancer.

METHODS

In this phase 2 trial, we evaluated the antitumor activity and safety of tarlatamab, administered intravenously every 2 weeks at a dose of 10 mg or 100 mg, in patients with previously treated small-cell lung cancer. The primary end point was objective response (complete or partial response), as assessed by blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1.

RESULTS

Overall, 220 patients received tarlatamab; patients had previously received a median of two lines of treatment. Among patients evaluated for antitumor activity and survival, the median follow-up was 10.6 months in the 10-mg group and 10.3 months in the 100-mg group. An objective response occurred in 40% (97.5% confidence interval [CI], 29 to 52) of the patients in the 10-mg group and in 32% (97.5% CI, 21 to 44) of those in the 100-mg group. Among patients with an objective response, the duration of response was at least 6 months in 59% (40 of 68 patients). Objective responses at the time of data cutoff were ongoing in 22 of 40 patients (55%) in the 10-mg group and in 16 of 28 patients (57%) in the 100-mg group. The median progression-free survival was 4.9 months (95% CI, 2.9 to 6.7) in the 10-mg group and 3.9 months (95% CI, 2.6 to 4.4) in the 100-mg group; the estimates of overall survival at 9 months were 68% and 66% of patients, respectively. The most common adverse events were cytokine-release syndrome (in 51% of the patients in the 10-mg group and in 61% of those in the 100-mg group), decreased appetite (in 29% and 44%, respectively), and pyrexia (in 35% and 33%). Cytokine-release syndrome occurred primarily during treatment cycle 1, and events in most of the patients were grade 1 or 2 in severity. Grade 3 cytokine-release syndrome occurred less frequently in the 10-mg group (in 1% of the patients) than in the 100-mg group (in 6%). A low percentage of patients (3%) discontinued tarlatamab because of treatment-related adverse events.

CONCLUSIONS

Tarlatamab, administered as a 10-mg dose every 2 weeks, showed antitumor activity with durable objective responses and promising survival outcomes in patients with previously treated small-cell lung cancer. No new safety signals were identified. (Funded by Amgen; DeLLphi-301 ClinicalTrials.gov number, NCT05060016.).

Tarlatamab, a First-in-Class DLL3-Targeted Bispecific T-Cell Engager, in Recurrent Small-Cell Lung Cancer: An Open-Label, Phase I Study

PURPOSE

Small-cell lung cancer (SCLC) is an aggressive malignancy with limited treatments. Delta-like ligand 3 (DLL3) is aberrantly expressed in most SCLC. Tarlatamab (AMG 757), a bispecific T-cell engager molecule, binds both DLL3 and CD3 leading to T-cellb-mediated tumor lysis. Herein, we report phase I results of tarlatamab in patients with SCLC.

PATIENTS AND METHODS

This study evaluated tarlatamab in patients with relapsed/refractory SCLC. The primary end point was safety. Secondary end points included antitumor activity by modified RECIST 1.1, overall survival, and pharmacokinetics.

RESULTS

By July 19, 2022, 107 patients received tarlatamab in dose exploration (0.003 to 100 mg; n = 73) and expansion (100 mg; n = 34) cohorts. Median prior lines of anticancer therapy were 2 (range, 1-6); 49.5% received antiprogrammed death-1/programmed death ligand-1 therapy. Any-grade treatment-related adverse events occurred in 97 patients (90.7%) and grade b % 3 in 33 patients (30.8%). One patient (1%) had grade 5 pneumonitis. Cytokine release syndrome was the most common treatment-related adverse event, occurring in 56 patients (52%) including grade 3 in one patient (1%). Maximum tolerated dose was not reached. Objective response rate was 23.4% (95% CI, 15.7 to 32.5) including two complete and 23 partial responses. The median duration of response was 12.3 months (95% CI, 6.6 to 14.9). The disease control rate was 51.4% (95% CI, 41.5 to 61.2). The median progression-free survival and overall survival were 3.7 months (95% CI, 2.1 to 5.4) and 13.2 months (95% CI, 10.5 to not reached), respectively. Exploratory analysis suggests that selecting for increased DLL3 expression can result in increased clinical benefit.

CONCLUSION

In patients with heavily pretreated SCLC, tarlatamab demonstrated manageable safety with encouraging response durability. Further evaluation of this promising molecule is ongoing.

Cisplatin-Induced Ototoxicity: A Concise Review of the Burden, Prevention, and Interception Strategies

Cisplatin is a bedrock of cancer management and one of the most used chemotherapeutic agents in the treatment of germ cell, lung, bladder, ovarian, and head and neck cancers. Approximately 500,000 patients diagnosed annually with these cancer types in the United States could be candidates for treatment with cisplatin. There is a 5-fold increase in the risk of hearing impairment or ototoxicity with cisplatin, which can manifest as ringing in the ear (tinnitus), high-frequency hearing loss, and at late stages, a decreased ability to hear normal conversation. More than half of adult and pediatric patients with cancer treated with cisplatin developed hearing impairment with major impact on patients' health-related quality of life. A considerable evidence gap persists regarding the burden and effective prevention and interception strategies for cisplatin-induced ototoxicity, especially in adult patients with cancer. We conducted a review of the published literature to provide an update on the status of this important clinical challenge. We also surveyed practicing oncologists within our network of academic and community practices to gain a better understanding of how the published literature compares with real-world practice. Our review of the literature showed a lack of standardized guidelines for monitoring and treatment of cisplatin-induced ototoxicity, especially in the adult cancer patient population. Our survey of practicing oncologists mirrored the findings from the published literature with a heterogeneity of practice, which highlights the need for standardization.

Abstract 4995: Targeting PLK1 effectively suppresses growth of small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive neuroendocrine tumor characterized by rapid disease progression and poor patient survival. Key transcription factors implicated as drivers of unique biological phenotypes of SCLC include ASCL1, NEUROD1, YAP1, and POU2F3. Strategies to exploit these phenotypes for innovative precision medicine approaches will be impactful. Using an unbiased agnostic preclinical drug screen to uncover therapeutic opportunities in SCLC, we identified a strong signal with PLK1 inhibitors (PLK1i) with low nanomolar IC50. We extended the in vitro findings by testing the efficacy of PLK1i in vivo using traditional xenograft of SCLC H526 cell line and patient derived xenografts (PDX). Volasertib achieved significant tumor growth inhibition relative to control in H526 xenografts. Also, onvansertib significantly inhibited growth of platinum-resistant and platinum-sensitive PDXs. The combination of PLK1i with standard chemotherapeutic agents identified promising synergy of the combination of onvansertib and paclitaxel. We further interrogated for predictive biomarkers of PLK1i sensitivity using gene expression profile comparing highly sensitive to less sensitive cell lines. High expression of C-MYC but not PLK1, TP53 or RB was associated with resistance to PLK1i. Conversely, while TP53 expression level did not correlate, TP53 gene mutation status (inactivating disruptive mutations) correlated with cell sensitivity to PLK1i. We queried the publicly available CCLE and the Cancer Therapeutics Response Portal to evaluate whether any of the SCLC subtypes have therapeutic vulnerability to PLK1i. In general, high expression of YAP1 in SCLC cell lines correlated with greater sensitivity to PLK1i. A YAP1 positive cell line, SW1271, with strong TP53 expression was particularly resistant to PLK1i. CRISPR knockout of YAP1 in this cell line enhanced SW1271 sensitivity to PLK1i suggesting that YAP1 expression as a marker of vulnerability to PLK1i could be context dependent especially when co-occurring with TP53 mutations. The mechanism of this interaction will be discussed.

Citation Format: John C. Schmitz, Guojing Zhang, Andrey A. Ivanov, Abbe Pannucci, Maya Ridinger, Taofeek K. Owonikoko. Targeting PLK1 effectively suppresses growth of small cell lung cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4995.

Serum glycomic profile as a predictive biomarker of recurrence in patients with differentiated thyroid cancer

PURPOSE

Thyroid cancer recurrence following curative thyroidectomy is associated with increased morbidity and mortality, but current surveillance strategies are inadequate for early detection. Prior studies indicate that tissue glycosylation is altered in thyroid cancer, but the utility of serum glycosylation in thyroid cancer surveillance remains unexplored. We therefore assessed the potential utility of altered serum glycomic profile as a tumor-specific target for disease surveillance in recurrent thyroid cancer.

EXPERIMENTAL DESIGN

We employed banked serum samples from patients with recurrent thyroid cancer post thyroidectomy and healthy controls. N-glycans were enzymatically released from serum glycoproteins, labeled via permethylation, and analyzed by MALDI-TOF mass spectrometry. Global level and specific subtypes of glycan structures were compared between patients and controls.

RESULTS

We evaluated 28 independent samples from 13 patients with cancer recurrence and 15 healthy controls. Global features of glycosylation, including N-glycan class and terminal glycan modifications were similar between groups, but three of 35 individual glycans showed significant differences. The three glycans were biosynthetically related biantennary core fucosylated N-glycans that only varied by the degree of galactosylation (G0F, G1F, and G2F; G: galactose, F: fucose). The ratio of G0F:G1F that captures reduced galactosylation was observed in patients samples but not in healthy controls (p = 0.004) and predicted thyroid cancer recurrence (AUC = 0.82, CI 95% = 0.64-0.99).

CONCLUSIONS

Altered N-glycomic profile was associated with thyroid cancer recurrence. This serum-based biomarker would be useful as an effective surveillance tool to improve the care and prognosis of thyroid cancer after prospective validation.

Clinical uptake of precision medicine advances in NSCLC: A case study in RET fusions

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Background: Precision medicine has revolutionized cancer care in advanced NSCLC and new actionable biomarkers and targeted therapies are emerging at an unprecedented pace, creating myriad opportunities to improve care and mitigate the often-dire sequelae of traditional cancer therapy. Delays in uptake of testing and biomarker-guided treatment for patients with NSCLC and EGFR activating mutations or ALK fusions are well documented despite clear evidence-based practice, guidelines, and expert recommendations. In this study, we analyze healthcare professionals (HCPs) awareness and application of RET fusion testing and integration of recently approved selective RET inhibitors into practice for appropriate patients with advanced NSCLC. Methods: From 1/2020-6/2022, multiple educational activities were developed to provide HCPs with evidence-based expert and guideline recommendations on assessment of and therapy selection for RET fusion–positive NSCLC. The activities comprised live symposia associated with 4 major oncology and pathology conferences (AMP, USCAP, ASCO, AACR), 3 regional live workshop series across the US, 3 live webinars, and 2 on-demand videos. Baseline polling questions designed to assess key aspects of HCP knowledge and practice patterns were repeated at each activity. Results: Across all activities at baseline, on average only 38% of responding HCPs correctly identified RNA NGS as the most sensitive testing assay for detection of RET fusions and 36% accurately selected the appropriate targeted therapy for patient case with a KIF5B-RET gene fusion. From 2020 through 2022, with each new group of learners across different scopes of practice, we found suboptimal awareness of optimal RET fusion testing methodology and choice of therapy for patients with RET fusion–positive NSCLC (table). Optimal responses were slightly higher among learners attending conference-associated symposia vs live workshop series and online education. Conclusions: The use of optimal testing assays for RET alterations across patients with NSCLC remains low and many HCPs continue to lack awareness of appropriate targeted therapy for patients with RET–fusion positive NSCLC > 2 years after the first approved indication for this biomarker. These results underscore a lag in adoption of optimal precision medicine approaches for NSCLC among oncology HCPs and the need for expert guidance and educational activities to optimize individualized, biomarker-driven treatment approaches. An analysis of patterns by HCP role (MD, NP/PA, RN, Pharmacist) will be presented.[Table: see text]

Phase I trial of the DLL3/CD3 bispecific T-cell engager BI 764532 in DLL3-positive small-cell lung cancer and neuroendocrine carcinomas

Poorly differentiated neuroendocrine carcinomas such as small-cell lung cancer (SCLC) have poor survival and high relapse rates. DLL3 is found on these carcinomas and has become a target of increasing interest in recent years. The bispecific DLL3/CD3 T-cell engager BI 764532 has been shown to induce complete tumor regression in a human T cell-engrafted mouse model. Here, we describe the study design of a first-in-human, phase I, multicenter, open-label, non-randomized, dose-escalation study in patients with SCLC or other DLL3-positive neuroendocrine carcinomas. The study will determine the maximum tolerated dose and evaluate safety, tolerability, pharmacokinetics and preliminary efficacy of BI 764532 monotherapy.

Pan-cancer analysis of YAP1 expression as a predictive biomarker for cancer immunotherapy

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Background: High YAP1 expression correlates with the ‘T-cell inflamed’ expression phenotype in small cell lung cancer (SCLC), but its association with other biomarkers of immune checkpoint vulnerability and in tumor types beyond SCLC is not known. We examined whether YAP1 expression correlates with other established markers of immune checkpoint blockade (ICB) efficacy (PDL1 expression and TMB) in a tumor agnostic manner to determine clinical relevance. Methods: Next-generation sequencing of DNA (592 gene panel or whole exome) and RNA (whole transcriptome) was performed for patient samples (n = 57,134), representing 13 cancer types, submitted to a CLIA-certified laboratory (Caris Life Sciences, Phoenix, AZ). The ‘T-cell inflamed’ signature (TIS) score was calculated as an 18-gene weighted coefficient composite value (Cristescu, 2018). PDL1 expression was assessed by immunohistochemistry (IHC) with cancer type-specific antibodies and thresholds, and high tumor mutational burden was defined as ≥10 mut/Mb. Patients were stratified into subgroups based on median YAP1 expression (YAP1-High/YAP-Low) within each cancer type. Significance was tested by Chi-square, Fisher’s exact test, or Mann-Whitney U test. Results: YAP1-High tumors were associated with significantly increased TIS scores compared to YAP1-Low across all 13 cancer types examined, with the largest fold increase observed in SCLC (1.33-fold, p < 0.0001), followed by pancreatic cancer (1.28-fold, p < 0.0001), while the smallest occurred in melanoma (1.13-fold, p < 0.0001). Spearman correlation strength (range 0.23-0.57) between YAP expression and TIS scores was consistent with increased TIS scores in YAP1-High samples. TMB-High rates were similar in YAP-High and YAP1-Low subgroups for most cancer types, with slightly lower rates in YAP1-High tumors observed for endometrial (23.0 vs 26.6%, p < 0.001) and esophageal (7.0 vs 9.5%, p < 0.05) cancers. YAP1 expression was not significantly increased in PDL1+ (IHC) tumors for most cancer types. However, significantly decreased YAP1 expression was associated with PDL1+ samples in RCC (Renal Cell Carcinoma) (0.91-fold change, P < 0.05), MM (0.90-fold change, P < 0.001), and ENCA (0.80-fold change, P < 0.0001) Conclusions: Our analyses provide confirmation that YAP1 expression positively correlates with the ‘T-cell inflamed’ phenotype across many cancer types, including those with approvals for (ICB) therapy. YAP1 expression was independent of established markers of ICB response, including TMB and PDL1. Further analysis of YAP1 expression as an additional tumor agnostic predictive biomarker is warranted.

Clinical application of precision medicine among oncologists: A case study in RET-targeted therapy

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Background: Precision medicine has revolutionized cancer care across multiple tumor types and new actionable biomarkers and targeted therapies are emerging at an unprecedented pace, creating myriad opportunities to optimize care and mitigate the often-dire sequelae of traditional cancer therapy. Many oncology healthcare professionals (HCPs) in practice are not employing optimal testing methodologies to detect biomarkers in patients who could benefit from novel targeted therapies. In this study, we analyze HCP awareness and application of RET alteration testing and integration of recently approved, new-generation selective RET inhibitors into practice for appropriate patients with NSCLC and thyroid cancer. Methods: In August 2020 HCPs were surveyed on RET alteration testing and use of RET-targeted therapeutics in their current practice. Study eligibility criteria included active HCPs in an oncology, pulmonology, or pathology practice. A curriculum of live and online educational activities was then developed for any interested oncologists and pathologists on RET alteration testing and/or targeted therapy for RET-altered lung and thyroid cancers. These activities included case studies, polling, and evaluations that provided additional insight on self-identified practice trends. In June 2021, at the completion of the educational program, eligible HCPs were surveyed again on RET alteration testing and selection of RET inhibitor therapy for appropriate patients. Results: In August 2020, 123 practicing HCPs completed the initial survey and 33% were testing patients for RET gene alterations and 18% were aware of the most sensitive testing assay for detection of RET fusions. 25% and 7%, respectively, were aware of the current indications for RET inhibitors in RET fusion–positive NSCLC and RET-altered thyroid cancer. Self-identified practice trends identified among the unselected cohort of 12,537 individual HPCs participating in the educational activities also demonstrated similar lack of appropriate testing for RET alterations and use of RET inhibitors. In June 2021, 60 practicing HCPs completed the follow-up survey and 40% were testing patients for RET gene alterations and 25% were aware of the most sensitive testing assay for detection of RET fusions. 52% and 22%, respectively, were aware of the current indications for RET inhibitors in RET fusion–positive NSCLC and RET-altered thyroid cancer. Conclusions: The rate of broad testing for RET alterations across patients with NSCLC and thyroid cancer remains low and many HCPs lack understanding of when to consider treating with a RET inhibitor. These results underscore the lag in adoption of optimal precision medicine approaches in oncology and the need for expert guidance and educational activities to optimize individualized, biomarker-driven treatment approaches for patients with cancer.

Surfaceome profiling to reveal unique therapeutic vulnerabilities in transcriptional subtypes of small cell lung cancer (SCLC)

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Background: Effective treatment options for SCLC remain limited and new treatment approaches are needed to improve outcome. We sought to validate the initial observation in cell lines and limited tissue samples of SCLC of a differential expression of cancer/testis (CT) antigens and TACSD2 gene that encodes surface protein, Trop2 across various subtypes of SCLC. We also tested whether overall surfaceome profile as previously described in other tumor types will show hierarchical priority of expression between transcriptionally defined SCLC subtypes. Methods: We conducted a comprehensive surfaceome profiling of SCLC samples using data generated by RNA sequencing (whole transcriptome) at Caris Life Sciences (Phoenix, AZ). SCLC tumors were stratified into 5 subgroups (SCLC-A/N/Y/P and -mixed) based on the relative expression of the four transcription factors. Expression values were converted to z-scores (the expression value for each gene is normalized to the average expression of that specific gene such that the z-score reflects the number of standard deviations above or below the average). The highest positive z-score among the 4 transcription factors determined subgroup. If all transcription factor z-scores for a given sample were negative, the sample was assigned to ‘Mixed’ subgroup. Significance was tested by Chi-square, Fisher’s exact test, or Mann-Whitney U test. Results: We employed data generated from 674 SCLC samples; median age of 66 years and male (48.7%). The SCLC subtype distribution was 241 (35.8%), 120 (17.8%), 40 (5.9%), 143 (21.2%), 130 (19.3%) for types A, N, P, Y and mixed respectively. Supervised analysis for TACSTD2 expression showed highest levels in YAP1 subtype and was overall significantly increased in SCLC-Y (̃3-fold) and SCLC-P (̃2-fold) subtypes compared to A, N and mixed subtypes. Similarly, SCLC-Y subtype showed the highest median expression as well as the strongest correlation with most TACSTD2-interacting and regulatory genes. A top 10 list of candidate surface protein gene out of 3699 surfaceome genes was defined for each subtype based on the strength of correlation. The top candidate surface protein gene and CT antigen gene respectively by subtype were: SCN3A (r = 0.7033, p = 1.08E-101) and NOL4, (r = 0.574, p = 2.46E-60) for SCLC-A; SSTR2, (r = 0.742, p = 8.18E-119) and TMEFF1, (r = 0.3601, p = 4.53E-22) for SCLC-N; TMPRSS13 (r = 0.5699, p = 2.64E-59) and LY6K (r = 0.4778, p = 9.80E-40) for SCLC-P; and CYBRD1 (r = 0.8559, p = 1.18E-194) and CTAGE5 (r = 0.5521, p = 4.95E-55) for SCLC-Y. Conclusions: SCLC-Y subtype showed the highest expression of TACSTD2 and its interacting and regulatory genes. This subtype could serve as an enrichment factor for antibody-drug-construct targeting TROP2. Several candidate CT antigens and surfaceome genes showing strong correlation with lineage-defining transcription factors offer additional therapeutic targets in SCLC.

Comparison of sociodemographic characteristics of a phase 1 clinical trial population at an NCI-designated comprehensive cancer center in the Southeast to catchment area

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Background: Racial and ethnic minority populations are consistently under-represented in oncology clinical trials despite comprising a disproportionate share of cancer burden. Due in part to difficulties associated with participation, phase 1 trials pose a unique challenge and opportunity for minority inclusion. Here we examine the sociodemographics of phase 1 clinical trial patients at an NCI-designated Comprehensive Cancer Center compared to all patients treated at the center, patients with new cancer diagnoses in metropolitan Atlanta, and the state of Georgia (GA). Methods: Patients enrolled on phase 1 trials at the Winship Cancer Institute (WCI) from 2015-2020, identified from a data warehouse, were compared to new patient registrations at WCI from 2015-2019. Patients with cancer in metro Atlanta and GA were identified from the Surveillance, Epidemiology, and End Results (SEER) Program: Nov 2018 Submission. Covariates for the phase 1 and institutional cohort included sex, race, ECOG PS, insurance, and age at consent. Covariates for SEER patients included sex, race, and age at diagnosis. Summary statistics are reported for categorical variables using frequencies and percentages, and for continuous variables using mean, median, standard deviation, and range. One-sample proportion tests were utilized to compare observed demographic proportions on phase 1 trials with proportions calculated from new patient registrations at WCI and from SEER case data. Results: From 2015-2020, 2325 patients (43.4% F, 56.6% M) signed consent for phase 1 trials. Grouped race distribution was 70.3% White, 26.2% Black, 3.5% Other. Insurance distribution was 42.9% private, 48% government, 9.1% uninsured/other. Mean age at consent was 61.7 years (MD 63, ran 19-92). Of new patient registrations at WCI in 2015 ( N= 12358) (49.7% F, 50.3% M), grouped race distribution was 64.0% W, 28.2% B, 8% O. Atlanta 2015 SEER patients ( N= 31101) (50.3%F, 49.7%M) showed grouped race distribution 58.4% W, 37.2% B, 4.3% O. Mean age at diagnosis was 62.9. GA 2015 SEER patients ( N= 99487) (48.6%F, 51.4%M) showed grouped race distribution 71.2% W, 26.7% B, 2.1% O. Mean age at diagnosis was 64.2. The race and sex distribution of phase 1 patients was significantly different than proportions calculated from new patient registrations at WCI and SEER data from patients in Atlanta ( p< 0.001). Sex distribution was significantly different than GA SEER patients. Conclusions: Phase 1 patients were significantly more likely to be white and male, compared with patients treated at the cancer center, as well as patients with cancer in Atlanta. Race distribution was not significantly different from patients with cancer in GA. Our intent is to characterize existing disparities in order to increase representation of patients from racial and ethnic minority backgrounds in phase 1 clinical trials.

Systematic discovery of mutation-directed neo-protein-protein interactions in cancer

Comprehensive sequencing of patient tumors reveals genomic mutations across tumor types that enable tumorigenesis and progression. A subset of oncogenic driver mutations results in neomorphic activity where the mutant protein mediates functions not engaged by the parental molecule. Here, we identify prevalent variant-enabled neomorph-protein-protein interactions (neoPPI) with a quantitative high-throughput differential screening (qHT-dS) platform. The coupling of highly sensitive BRET biosensors with miniaturized coexpression in an ultra-HTS format allows large-scale monitoring of the interactions of wild-type and mutant variant counterparts with a library of cancer-associated proteins in live cells. The screening of 17,792 interactions with 2,172,864 data points revealed a landscape of gain of interactions encompassing both oncogenic and tumor suppressor mutations. For example, the recurrent BRAF V600E lesion mediates KEAP1 neoPPI, rewiring a BRAF^V600E/KEAP1 signaling axis and creating collateral vulnerability to NQO1 substrates, offering a combination therapeutic strategy. Thus, cancer genomic alterations can create neo-interactions, informing variant-directed therapeutic approaches for precision medicine.

Telaglenastat Plus Cabozantinib or Everolimus for Advanced or Metastatic Renal Cell Carcinoma: An Open-Label Phase I Trial

PURPOSE

Dual inhibition of glucose and glutamine metabolism results in synergistic anticancer effects in solid tumor models. Telaglenastat, an investigational, small-molecule, glutaminase inhibitor, exhibits modest single-agent activity in renal cell carcinoma (RCC) patients. This phase Ib trial evaluated telaglenastat plus cabozantinib or everolimus, agents known to impair glucose metabolism in patients with metastatic RCC (mRCC).

PATIENTS AND METHODS

mRCC patients received escalating doses of telaglenastat [400-800 mg per os (p.o.) twice daily] in a 3 + 3 design, plus either everolimus (10 mg daily p.o.; TelaE) or cabozantinib (60 mg daily p.o.; TelaC). Tumor response (RECISTv1.1) was assessed every 8 weeks. Endpoints included safety (primary) and antitumor activity.

RESULTS

Twenty-seven patients received TelaE, 13 received TelaC, with median 2 and 3 prior therapies, respectively. Treatment-related adverse events were mostly grades 1 to 2, most common including decreased appetite, anemia, elevated transaminases, and diarrhea with TelaE, and diarrhea, decreased appetite, elevated transaminases, and fatigue with TelaC. One dose-limiting toxicity occurred per cohort: grade 3 pruritic rash with TelaE and thrombocytopenia with TelaC. No maximum tolerated dose (MTD) was reached for either combination, leading to a recommended phase II dose of 800-mg telaglenastat twice daily with standard doses of E or C. TelaE disease control rate (DCR; response rate + stable disease) was 95.2% [20/21, including 1 partial response (PR)] among 21 patients with clear cell histology and 66.7% (2/3) for papillary. TelaC DCR was 100% (12/12) for both histologies [5/10 PRs as best response (3 confirmed) in clear cell].

CONCLUSIONS

TelaE and TelaC showed encouraging clinical activity and tolerability in heavily pretreated mRCC patients.

Assessment of hyperprogression versus the natural course of disease development with nivolumab with or without ipilimumab versus placebo in phase III, randomized, controlled trials

Background

Retrospective studies have suggested a potential risk of hyperprogressive disease (HPD) in patients receiving immune checkpoint inhibitors (ICIs). We compared the incidence of HPD during treatment with nivolumab±ipilimumab versus natural tumor progression with placebo in post hoc analyses of two randomized, double-blind clinical trials.

Methods

ATTRACTION-2 randomized patients with advanced gastric or gastroesophageal junction cancer (GC/GEJC) and progression on ≥2 prior regimens to nivolumab 3 mg/kg Q2W or placebo. CheckMate 451 randomized patients with extensive-disease small cell lung cancer (ED SCLC) and ongoing complete/partial response or stable disease after first-line chemotherapy to nivolumab 240 mg Q2W, nivolumab 1 mg/kg+ipilimumab 3 mg/kg Q3W for four doses then nivolumab 240 mg Q2W, or placebo. Patients receiving ≥1 dose of study drug and with tumor scans at baseline and the first on-treatment evaluation were included in the HPD analyses. HPD definitions were ≥20%, ≥50%, and ≥100% increase in target lesion sum of the longest diameters (SLD) at the first on-treatment assessment.

Results

In the ATTRACTION-2 HPD-evaluable population, 243 patients received nivolumab and 115 placebo. Fewer patients receiving nivolumab versus placebo had increases in SLD ≥20% (33.7% vs 46.1%) and ≥50% (6.2% vs 11.3%); similar proportions had increases in SLD ≥100% (1.6% vs 1.7%). In the CheckMate 451 HPD-evaluable population, 177 patients received nivolumab, 179 nivolumab+ipilimumab, and 175 placebo. Fewer patients receiving nivolumab or nivolumab+ipilimumab versus placebo had increases in SLD ≥20% (27.1%, 27.4% vs 45.7%), ≥50% (10.2%, 11.2% vs 22.3%), and ≥100% (2.8%, 2.8% vs 6.3%).

Conclusions

Nivolumab±ipilimumab was not associated with an increased rate of progression versus placebo in patients with GC, GEJC, or ED SCLC, suggesting that previous reports of HPD may reflect the natural disease course in some patients rather than ICI-mediated progression.

Trial registration number

NCT02538666; NCT02267343.

Induction of SREBP1 degradation coupled with suppression of SREBP1-mediated lipogenesis impacts the response of EGFR mutant NSCLC cells to osimertinib

Emergence of acquired resistance to osimertinib (AZD9291), the first-approved third-generation EGFR inhibitor that selectively and irreversibly inhibits the activating EGFR mutations and the resistant T790M mutation, is a giant and urgent clinical challenge. Fully understanding the biology underlying the response of EGFR mutant non-small cell lung cancer (NSCLC) to osimertinib is the foundation for development of mechanism-driven strategies to overcome acquired resistance to osimertinib or other third-generation EGFR inhibitors. This study focused on tackling this important issue by elucidating the critical role of sterol regulatory element-binding protein 1 (SREBP1) degradation in conferring the response of EGFR mutant NSCLC cells to osimertinib and by validating the strategy via directly targeting SREBP1 for overcoming osimertinib acquired resistance. Osimertinib facilitated degradation of the mature form of SREBP1 (mSREBP1) in a GSK3/FBXW7-dependent manner and reduced protein levels of its regulated genes in EGFR-mutant NSCLC cells/tumors accompanied with suppression of lipogenesis. Once resistant, EGFR-mutant NSCLC cell lines possessed elevated levels of mSREBP1, which were resistant to osimertinib modulation. Both genetic and pharmacological inhibition of SREBP1 sensitized osimertinib-resistant cells and tumors to osimertinib primarily through enhancing Bim-dependent induction of apoptosis, whereas enforced expression of ectopic SREBP1 in sensitive EGFR-mutant NSCLC cells compromised osimertinib's cell-killing effects. Collectively, we have demonstrated a novel connection between osimertinib and SREBP1 degradation and its impact on the response of EGFR mutant NSCLC cells to osimertinib and suggested an effective strategy for overcoming acquired resistance to osimertinib, and possibly other EGFR inhibitors, via targeting SREBP1.

Advances in Treatment of Recurrent Small Cell Lung Cancer (SCLC): Insights for Optimizing Patient Outcomes from an Expert Roundtable Discussion

Second-line treatment options for patients with relapsed, extensive-stage small cell lung cancer (ES-SCLC) are limited, and even with currently available treatments, prognosis remains poor. Until recently, topotecan (a topoisomerase I inhibitor) was the only drug approved by the United States (US) Food and Drug Administration (FDA) for the management of ES-SCLC following progression after first-line treatment with etoposide plus a platinum derivative (EP; carboplatin preferred). With the most recent approval of EP plus a programmed death ligand 1 (PD-L1) inhibitor, there are now more therapeutic options for managing ES-SCLC. A number of novel agents have emerging data for activity in relapsed ES-SCLC, and single-agent lurbinectedin (an alkylating drug and selective inhibitor of oncogenic transcription and DNA repair machinery in tumor cells) has conditional FDA approval for use in this patient population. Trilaciclib, a short-acting cyclin-dependent kinase 4/6 (CDK 4/6) inhibitor, has also been recently approved as a supportive intervention for use prior to an EP or a topotecan-containing regimen to diminish the incidence of chemotherapy-induced myelosuppression. The current review is based on a recent expert roundtable discussion and summarizes current therapeutic agents and emerging data on newer agents and biomarkers. It also provides evidence-based clinical considerations and a treatment decision tool for oncologists treating patients with relapsed ES-SCLC. This paper discusses the importance of various factors to consider when selecting a second-line treatment option, including prior first-line treatment, available second-line treatment options, tumor platinum sensitivity, and patient characteristics (such as performance status, comorbidities, and patient-expressed and perceived values).

Expression of tdTomato and luciferase in a murine lung cancer alters the growth and immune microenvironment of the tumor

Imaging techniques based on fluorescence and bioluminescence have been important tools in visualizing tumor progression and studying the effect of drugs and immunotherapies on tumor immune microenvironment in animal models of cancer. However, transgenic expression of foreign proteins may induce immune responses in immunocompetent syngeneic tumor transplant models and augment the efficacy of experimental drugs. In this study, we show that the growth rate of Lewis lung carcinoma (LL/2) tumors was reduced after transduction of tdTomato and luciferase (tdTomato/Luc) compared to the parental cell line. tdTomato/Luc expression by LL/2 cells altered the tumor microenvironment by increasing tumor-infiltrating lymphocytes (TILs) while inhibiting tumor-induced myeloid-derived suppressor cells (MDSCs). Interestingly, tdTomato/Luc expression did not alter the response of LL/2 tumors to anti-PD-1 and anti-CTLA-4 antibodies. These results suggest that the use of tdTomato/Luc-transduced cancer cells to conduct studies in immune competent mice may lead to cell-extrinsic tdTomato/Luc-induced alterations in tumor growth and tumor immune microenvironment that need to be taken into consideration when evaluating the efficacy of anti-cancer drugs and vaccines in immunocompetent animal models.

Physician Communication and Patient Understanding of Molecular Testing Terminology

BACKGROUND

The use of molecular testing in oncology is rapidly expanding. The aim of this study was to determine how oncologists describe molecular testing and whether patients understand the terminology being used.

MATERIALS AND METHODS

Sixty conversations between oncologists and patients about molecular testing were observed, and the used technical terms were noted by the researcher. Patients were interviewed post-conversation to assess their understanding of the noted technical terms. A patient understanding score was calculated for each participant. Comparisons of the terms were conducted using χ² tests, Fisher's exact tests, or ANOVA when appropriate.

RESULTS

Sixty-one unique technical terms were used by oncologists, to describe seven topics. "Mutation" was a challenging term for patients to understand with 48.8% (21/43 mentions) of participants correctly defining the term. "Genetic testing" and "Gene" were understood a little more than half the time (53.3%; 8/15 and 56.4%; 22/39 respectively). "DNA" was well understood (80%; 12/15). There was no correlation between the terms being defined by the oncologist in the conversation, and the likelihood of the patient providing a correct definition. White participants were significantly more likely to understand both "mutation" and "genetic testing" than non-White participants. Forty-two percent (n = 25) of participants had an understanding score below 50%, and a higher family income was significantly correlated with a higher score.

CONCLUSION

Our results show that oncologists use variable terminology to describe molecular testing, which is often not understood. Because oncologists defining the terms did not correlate with understanding, it is imperative to develop new, improved methods to explain molecular testing.

IMPLICATIONS FOR PRACTICE

The use of molecular testing is expanding in oncology, yet little is known about how effectively clinicians are communicating information about molecular testing and whether patients understand the terminology used. The results of this study indicate that patients do not understand some of the terminology used by their clinicians and that clinicians tend to use highly variable terminology to describe molecular testing. These results highlight the need to develop and implement effective methods to explain molecular testing terminology to patients to ensure that patients have the tools to make autonomous and informed decisions about their treatment.

Discovery of Small Molecule Bak Activator for Lung Cancer Therapy

Rationale: Bak is a major proapoptotic Bcl2 family member and a required molecule for apoptotic cell death. High levels of endogenous Bak were observed in both small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) cell lines. Increased Bak expression was correlated with poor prognosis of NSCLC patients, suggesting that Bak protein is an attractive target for lung cancer therapy. The BH3 domain functions as death domain and is required for Bak to initiate apoptotic cell death. Thus, the BH3 domain is attractive target for discovery of Bak agonist.

Methods: The BH3 death domain binding pocket (aa75-88) of Bak was chosen as a docking site for screening of small molecule Bak activators using the UCSF DOCK 6.1 program suite and the NCI chemical library (300,000 small molecules) database. The top 500 compounds determined to have the highest affinity for the BH3 domain were obtained from the NCI and tested for cytotoxicity for further screening. We identified a small molecule Bak activator BKA-073 as the lead compound. The binding affinity of BKA-073 with Bak protein was analyzed by isothermal titration calorimetry (ITC) assay. BKA-073-mediated Bak activation via oligomerization was analyzed by a cross-linking with Bis (maleimido) hexane (BMH). Sensitivity of BKA-073 to lung cancer cells in vitro was evaluated by dynamic BH3 profiling (DBP) and apoptotic cell death assay. The potency of BKA-073 alone or in combination with radiotherapy or Bcl2 inhibitor was evaluated in animal models.

Results: We found that BKA-073 binds Bak at BH3 domain with high affinity and selectivity. BKA-073/Bak binding promotes Bak oligomerization and mitochondrial priming that activates its proapoptotic function. BKA-073 potently suppresses tumor growth without significant normal tissue toxicity in small cell lung cancer (SCLC) and NSCLC xenografts, patient-derived xenografts, and genetically engineered mouse models of mutant KRAS-driven cancer. Bak accumulates in radioresistant lung cancer cells and BKA-073 reverses radioresistance. Combination of BKA-073 with Bcl-2 inhibitor venetoclax exhibits strong synergy against lung cancer in vivo.

Conclusions: Development of small molecule Bak activator may provide a new class of anticancer agents to treat lung cancer.

Targeting c-Myc to overcome acquired resistance of EGFR mutant NSCLC cells to the third generation EGFR tyrosine kinase inhibitor, osimertinib

Osimertinib (AZD9291 or TAGRISSOTM) is a promising and approved third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for treating patients with advanced non-small cell lung cancer (NSCLC) harboring EGFR-activating mutations or the resistant T790M mutation. However, the inevitable emergence of acquired resistance limits its long-term efficacy. A fuller understanding of the mechanism of action of osimertinib and its linkage to acquired resistance will enable the development of more efficacious therapeutic strategies. Consequently, we have identified a novel connection between osimertinib or other EGFR TKI and c-Myc. Osimertinib rapidly and sustainably decreased c-Myc levels primarily via enhancing protein degradation in EGFR-mutant (EGFRm) NSCLC cell lines and xenograft tumors. c-Myc levels were substantially elevated in different EGFRm NSCLC cell lines with acquired resistance to osimertinib in comparison with their corresponding parental cell lines and could not be reduced any further by osimertinib. Consistently, c-Myc levels were elevated in the majority of EGFRm NSCLC tissues relapsed from EGFR-TKI treatment compared to their corresponding untreated baseline c-Myc levels. Suppression of c-Myc through knockdown or pharmacological targeting with BET inhibitors restored the response of resistant cell lines to osimertinib. These findings indicate that c-Myc modulation mediates the therapeutic efficacy of osimertinib and the development of osimertinib-acquired resistance. Furthermore, they establish c-Myc as a potential therapeutic target and warrant clinical testing of BET inhibition as a potential strategy to overcome acquired resistance to osimertinib or other EGFR inhibitors.

Abstract CT219: Master protocol to assess the safety and recommended Phase 2 dose of next generation NY-ESO-1-specific TCR T-cells in HLA-A*02 patients with synovial sarcoma and non-small cell lung cancer

Background: Letetresgene autoleucel (lete-cel; GSK3377794) is an autologous T-cell therapy expressing a genetically modified T-cell receptor (TCR) to improve recognition of cancer cells expressing NY-ESO-1 and/or LAGE-1a. Next generation NY-ESO-1 TCR T-cell therapies, including GSK3901961 and GSK3845097, incorporate further genetic modifications to enhance anticancer activity. GSK3901961 co-expresses the CD8α chain to stabilize TCR-human leukocyte A (HLA) class I interactions on CD4+ T cells, enhancing T-cell persistence and increasing helper functions such as Type 1 T-helper anti-tumor responses. GSK3845097 co-expresses a dominant negative transforming growth factor-β (TGF-β) type II receptor to reduce TGF-β pathway activation and maintain T-cell proliferation, cytokine production, and cytotoxicity in the tumor microenvironment. A first-time-in-human master protocol (NCT04526509) will evaluate the safety, tolerability, and recommended Phase 2 dose (RP2D) of these two therapies and possible subsequent ones. Substudy 1 will assess GSK3901961 in patients with advanced non-small cell lung cancer (NSCLC) or synovial sarcoma (SS). Substudy 2 will assess GSK3845097 in patients with advanced SS.

Methods: Each substudy includes a dose confirmation stage to assess RP2D and a dose expansion stage. Table 1 lists eligibility criteria. Primary endpoints are safety (adverse events) and tolerability (dose-limiting toxicities). Secondary endpoints include investigator-assessed overall response rate, duration of response, and maximum expansion/persistence and phenotype of infiltrating transduced T cells. Exploratory endpoints include laboratory parameters, overall survival, and anti-GSK3901961 and anti-GSK3845097 titers for the respective substudies. The substudies are open and recruiting.

Funding: GSK (209012; NCT04526509)

Initial screening criteriaInclusion criteriaExclusion criteriaSubstudies 1 and 2 (SS and NSCLC)≥18 years of agePrior malignancy that is not in complete remission or clinically significant systemic illnessMeasurable disease per RECIST v1.1 criteriaPrevious treatment with genetically modified NY-ESO-1-specific T cells, NY-ESO-1 vaccine, or NY-ESO-1 targeting antibodyExpression of HLA-A*02:01, A*02:05, or A*02:06Prior gene therapy using an integrating vectorExpression of NY-ESO-1/LAGE-1a in tumor archival or fresh biopsyPrevious allogeneic hematopoietic stem cell transplant within the last 5 years or solid organ transplantSubstudies 1 and 2 (SS only)Histologically confirmed advanced (metastatic or unresectable) SS diagnosisCentral nervous system metastasesPresence of t(X;18) translocation(Allowed for NSCLC participants on a case-by-case basis)Received, completed, or intolerant to treatment with anthracycline or anthracycline with ifosfamide for advanced (metastatic or unresectable) disease and has progressedSubstudy 1 (NSCLC only)Histologically or cytologically confirmed Stage IV NSCLCReceived or failed ≥3 lines of systemic therapyReceiving or previously received ≥1 prior line(s) of standard of care treatment including programmed death receptor-1/programmed death ligand-1 checkpoint blockade therapy, and received or be intolerant to doublet taxane and platinum chemotherapyPresence of actionable genetic aberration (activation epithelial growth factor receptor, anaplastic lymphoma kinase/c-ros oncogene 1) per NCCN guidelines

Citation Format: Adam J. Schoenfeld, Mehmet Altan, Taofeek K. Owonikoko, Sandra D'Angelo, Brian H. Ladle, Jonathan Noujaim, Kai He, David Liebner, Adrian G. Sacher, John B.A.G. Haanen, Jeffrey Yachnin, Chao Huang, Brian A. Van Tine, Aisha Hasan, Thomas Faitg, Emily Butler, Aiman Shalabi, Steven Attia, Dejka M. Araujo. Master protocol to assess the safety and recommended Phase 2 dose of next generation NY-ESO-1-specific TCR T-cells in HLA-A*02 patients with synovial sarcoma and non-small cell lung cancer [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 CT219.

Membrane-Associated RING-CH 8 Functions as a Novel PD-L1 E3 Ligase to Mediate PD-L1 Degradation Induced by EGFR Inhibitors

Expression of programmed death-ligand 1 (PD-L1) on cancer cells is a critical mechanism contributing to immunosuppression and immune escape. PD-L1 expression may also affect therapeutic outcomes of epidermal growth factor receptor (EGFR)-targeted therapy (e.g., with osimertinib/AZD9291) against EGFR-mutant non-small cell lung cancers (NSCLC) and can even be altered during the treatment albeit with largely undefined mechanisms. This study primarily focuses on elucidating the mechanism by which osimertinib induces PD-L1 degradation in addition to validating osimertinib's effect on decreasing PD-L1 expression in EGFR-mutant NSCLC cells and tumors. Osimertinib and other EGFR inhibitors effectively decreased PD-L1 levels primarily in EGFR-mutant NSCLCs and xenografted tumors. Osimertinib not only decreased PD-L1 mRNA expression, but also prompted proteasomal degradation of PD-L1 protein, indicating both transcriptional and posttranslational mechanisms accounting for osimertinib-induced reduction of PD-L1. Knockdown of β-TrCP or inhibition of GSK3 failed to prevent PD-L1 reduction induced by osimertinib. Rather, knockdown of membrane-associated RING-CH 8 (MARCH8) that encodes a membrane-bound E3 ubiquitin ligase rescued osimertinib-induced PD-L1 reduction. Furthermore, manipulation of MARCH8 expression accordingly altered PD-L1 degradation rate. Critically, MARCH8 interacted with PD-L1 through its N-terminal region and also ubiquitinated PD-L1 in cells. Collectively, these results strongly suggest that MARCH8 is a previously undiscovered E3 ubiquitin ligase responsible for PD-L1 degradation including osimertinib-induced PD-L1 degradation, establishing a novel connection between MARCH8 and PD-L1 regulation. IMPLICATIONS: This study has demonstrated a previously undiscovered function of MARCH8 in mediating PD-L1 degradation induced by EGFR inhibitors in EGFR-mutant NSCLC cells, establishing a novel connection between MARCH8 and PD-L1 regulation.

Master protocol to assess safety and recommended phase 2 dose of next generation NY-ESO-1–specific TCR T-cells in HLA-A*02 patients with synovial sarcoma or non-small cell lung cancer (Substudies 1 and 2)

TPS2661

Background: Letetresgene autoleucel (lete-cel; GSK3377794) is an autologous T-cell therapy using a genetically modified T-cell receptor (TCR) to improve recognition of cancer cells expressing NY-ESO-1/LAGE-1a. Next generation NY-ESO-1 TCR T-cell therapies, such as GSK3901961 and GSK3845097, integrate added genetic modifications to enhance anticancer activity. GSK3901961 co-expresses the CD8α chain to stabilize TCR-human leukocyte A (HLA) class I interactions on CD4+ T cells, improving T-cell persistence and helper functions such as Type 1 T-helper antitumor responses. GSK3845097 co-expresses a dominant negative transforming growth factor-β (TGF-β) type II receptor to reduce TGF-β pathway activation and maintain T-cell proliferation, cytokine production, and cytotoxicity in the tumor microenvironment. A first-time-in-human master protocol (NCT04526509) will evaluate safety, tolerability, and recommended phase 2 dose (RP2D) of these and possible subsequent therapies. Substudy 1 will assess GSK3901961 in patients (pts) with advanced non-small cell lung cancer (NSCLC) or synovial sarcoma (SS). Substudy 2 will assess GSK3845097 in pts with advanced SS. Methods: Each substudy includes a dose confirmation stage to assess RP2D and a dose expansion stage. Key inclusion criteria are age ≥18 y; measurable disease per RECIST v1.1; HLA-A*02:01, A*02:05, or A*02:06 positivity; NY-ESO-1/LAGE-1a tumor expression; advanced (metastatic/unresectable) SS with t(X;18) translocation and anthracycline-based therapy receipt/completion/intolerance (SS only); and Stage IV NSCLC, receipt of ≥1 prior line(s) of standard of care (SOC) therapy including programmed death receptor- or ligand-1 inhibitors, and SOC chemotherapy receipt/intolerance (Substudy 1 only). Key exclusion criteria are prior malignancy that is not in complete remission or clinically significant systemic illness; prior receipt of gene/NY-ESO-1–specific therapy or allogenic stem cell/solid organ transplant; central nervous system metastases (SS only); and actionable genetic aberration and receipt/failure of ≥3 systemic therapy lines (Substudy 1 only). Primary endpoints are safety (adverse events) and tolerability (dose-limiting toxicities). Secondary endpoints include investigator-assessed overall response rate, duration of response, and maximum expansion/persistence and phenotype of infiltrating transduced T cells. Exploratory endpoints include laboratory parameters, overall survival, and anti-GSK3901961 or -GSK3845097 titers as applicable. Analyses will be descriptive. The substudies are enrolling. Funding: GSK (209012; NCT04526509). Editorial support was provided by Eithne Maguire, PhD, of Fishawack Indicia, part of Fishawack Health; funded by GSK. Previously presented at AACR 2021 (CT219). Clinical trial information: NCT04526509.

Genomic and immunologic characterization of large-cell neuroendocrine carcinoma of the lung

8535

Background: Large-cell neuroendocrine carcinoma (LCNEC) is a rare type of lung cancer with a poor prognosis. Due to its rarity, molecular characterization of LCNEC is not well elucidated. We aim to understand the genomic and immunologic landscape of LCNEC to identify molecular alterations and relevant biological pathways with potential therapeutic value. Methods: Comprehensive profiling including whole exome sequencing (WES), next-generation sequencing (NGS), whole transcriptome sequencing (WTS), and immunohistochemistry (IHC) for PD-L1 was performed (Caris Life Sciences, Phoenix, AZ). Tumor mutational burden (TMB) was calculated based on somatic nonsynonymous mutations. LCNEC was categorized as small cell lung cancer (SCLC)-like LCNEC ( TP53/ RB1 co-mutated) and non-small-cell lung cancer (NSCLC)-like LCNEC (wild type for one or both of TP53/ RB1). Molecular features of LCNEC were compared among the subgroups and with those of SCLC using the χ2 test with Benjamini & Hochberg correction. Results: A total of 467 cases of LCNEC were included. Commonly altered genes (≥ 5%) included TP53 (79.1%), RB1 (36.8%), SMARCA4 (10.4%), ARID1A (10.3%), KRAS (9.7%), KEAP1 (9.2%), KMT2D (8.7%), STK11 (8.4%), NF1 (7.1%), PTEN (6.1%), and CDKN2A (5.9%) . The prevalence of potentially actionable mutations was as follows: EGFR exon 19 deletion (0.48%), EGFR L858R (0.48%), ALK fusion (1.7%), KRAS G12C (2.9%). EGFR exon 19 deletion, EGFR L858R, and ALK fusion were exclusive to NSCLC-like LCNEC tumors. RET fusion, NTRK fusion and BRAFV600E were not detected. Copy number alterations (CNAs) were found in MYC (8.8%), ZNF703 (4.1%), FOXA1 (4.0%), FGFR1 (4.0%), ATK2 (3.9%), CCNE1 (3.7%), FGF19 (3.4%), TNFRSF14 (3.4%), and CCND1 (2.7%). Over-expression of cMET was noted in 10% and PD-L1 expression (by 22C3 pharmDx) of > 1% was noted in 21.5% of samples. WTS detected cMET exon 14 skipping mutations in 2.4% of samples. High tumor mutation burden (TMB; ≥ 10 Mut/MB) was seen in 40.6%. Among the 467 cases of LCNEC, 112 (24%) were SCLC-like LCNEC and 335 (76%) NSCLC-like LCNEC. Mutations in KRAS (12%), STK11 (11%), CDKN2A (9%), and SMARCA4 (14%) were more common in NSCLC-like LCNEC, compared with SCLC-like LCNEC (p value < 0.05). 442 cases of SCLC were compared with LCNEC tumors. SLFN11:SLFN12 fusion events, detected by WTS, were exclusively seen in SCLC and were not seen in any of the LCNEC cases. Gene expression profiles revealed that 1) B cell infiltration was higher in SCLC-like LCNEC, compared with SCLC, and 2) NK and T cell infiltration was lower, but B-cell infiltration was higher in NSCLC-like LCNEC, compared with SCLC. Conclusions: LCNEC displays a broad pattern of genomic alterations that overlap in the SCLC-like subset with the classic alterations in SCLC. The distinct genomic alterations and transcriptomic profiles present opportunities for therapeutic targeting and inform a future framework for development of therapeutics for LCNEC.

Phase 1, 2 trial of concurrent anti-PD1 and stereotactic radiosurgery for melanoma and non-small cell lung cancer brain metastases (NCT02858869)

2022

Background: The safety and efficacy of concurrent pembrolizumab (anti-PD1) and stereotactic radiosurgery (SRS) for brain metastases (BM) is unknown. Methods: Patients with melanoma or NSCLC, 1-10 brain metastases, ≥ 1 extra-cranial lesion, age ≥ 18, and ECOG 0-1 were treated with anti-PD1 every 3 weeks. SRS was administered 1-2 days after starting anti-PD1. SRS used three different radiation arms: Arm A used 6 Gray (Gy) in 5 fractions (fx), Arm B used 9 Gy in 3 fx, and Arm C used 18-21 Gy in single fx. Primary endpoint was grade 3 CNS toxicity at 3 months (CTCAE v 4.0). Secondary endpoints were overall survival (OS), local control (LC) within the SRS field, intra-cranial progression free survival (IC-PFS), extra-cranial progression free survival (EC-PFS), rate of extra-cranial clinical benefit, and immunological changes. OS, LC, IC-PFS, and EC-PFS were estimated using the Kaplan-Meier method, and covariates were compared using log-rank tests. 95% confidence intervals for 6-month and 12-month were estimated using Greenwood’s formula. Results: 25 patients were treated from 2016 until 2020. The mean age was 61. The mean number of CNS lesions was 2.7. The mean number of extra-cranial lesions was 2.5. Six were enrolled on Arm A, 12 on Arm B, and 7 on Arm C. 21 had melanoma. 4 had NSCLC. Of the melanoma, 8 were BRAF-, 10 were BRAF+, and 3 had unknown mutation status. 12 patients (48%) had progressed on prior immunotherapy and/or other oncological therapies. The trial met its primary endpoint, with no grade 3 CNS toxicity at 3 months. Two patients (8%) experienced ≥ Grade 3 anti-PD1 related toxicity, and no grade 5 toxicity was noted. The median OS was 32.8 months. The 6 and 12 month OS were 79.1% (56.5-90.8%) and 67.8% (43.3-83.5%), respectively. The 1 year OS was similar between previously treated and treatment naïve patients (71.8% vs. 65.6%), suggesting some role for SRS in overcoming therapy resistance. However, with longer follow-up, the OS trended worse (p=0.07) for previously treated patients. LC was 95.7% (72.9-99.4%) at 6 and 12 months. IC-PFS at 6 months was 69.1% (45.8-83.9%), and at 12 months was 57.5% (33.7-75.5%). The EC-PFS at 6 and 12 month was 54.5% (32.1-72.4%) and 43.6% (22.3-63.2%), respectively. Clinical benefit, which was defined as a best overall response of stable disease or better according to RECIST 1.1, occurred in 12 patients (48%). No outcome differences were noted amongst the three different SRS arms. 70% of the patients demonstrating early activation (within 3 weeks of starting SRS/anti-PD1) of CD8+PD1+Ki67+ T cells demonstrated a clinical benefit. 100% of patients that failed to show early activation of CD8+PD1+Ki67+ T cells progressed. Conclusions: Concurrent pembrolizumab (Anti-PD-1) and SRS is safe and effective. Early activation of CD8+PD1+Ki67+ T cells correlates with improved outcome. Further trials testing pembrolizumab and SRS are justified. Clinical trial information: NCT02858869.

Updated results from a phase 1 study of AMG 757, a half-life extended bispecific T-cell engager (BiTE) immuno-oncology therapy against delta-like ligand 3 (DLL3), in small cell lung cancer (SCLC)

8510

Background: DLL3, an inhibitory Notch ligand, is a promising target as it is highly expressed in SCLC compared to normal tissue. AMG 757, a half-life extended BiTE immuno-oncology therapy, binds DLL3 on tumor cells and CD3 on T cells, leading to T cell-dependent killing of tumors. Results from the first nine dosing cohorts showing preliminary efficacy of AMG 757 (confirmed partial response [PR], 14% of pts) were previously presented. Here, updated safety, efficacy, and pharmacokinetic data from 10 cohorts from the ongoing phase 1 study of AMG 757 in SCLC are reported (NCT03319940). Methods: AMG 757 (0.003–100 mg) was administered IV every 2 weeks ± step dosing. Eligible patients (pts) had SCLC that progressed after ≥1 platinum-based regimen. Antitumor activity was assessed by modified RECIST 1.1. Results: As of 11 Jan 2021, 64 pts enrolled at 10 dose levels (DLs; 0.003–100 mg) had received ≥1 AMG 757 dose and were available for analyses. Median age was 64 (range, 32–80) y; 63 pts (98%) had ECOG PS 0–1 and median number of prior lines of therapy was 2 (range, 1–6), with 28 pts (44%) receiving prior PD-1/PD-L1 therapy. Median treatment duration was 6 (range, 0.1–71) wk. Treatment-related AEs occurred in 53 pts (83%): 16 (25%) ≥ grade (G) 3, 4 (6%) ≥G4, 1 (2%) G5 (pneumonitis; DL5 [0.3 mg]). AEs led to discontinuation in 1 pt (G3 encephalopathy, DL10 [100 mg]). Cytokine release syndrome (CRS; graded per Lee 2014 criteria) was reported in 27 pts (42%): G2 in 7 (11%), ≥G3 in 1 (2%). CRS presented mainly as fever (31%), tachycardia (17%), nausea (13%), fatigue (9%), and hypotension (9%). CRS was usually reversible and was managed with supportive care, corticosteroids, and/or anti-IL-6R. CRS did not lead to any treatment discontinuations. Sixty pts treated across 10 DLs, with a median follow-up of 4.2 (range, 0.2–18.6) mo, were evaluated for efficacy. Confirmed PR across all DLs was reported in 8/60 pts (13%), with 5/8 pts (63%) pts achieving unconfirmed PR at 100 mg (DL10). The median time to response was 1.7 (range, 1.2–3.7) mo. The estimated duration of response was >6 months in 71% pts (95% CI: 26, 92) with any PR. Disease control rate was 43%, with any tumor shrinkage in 23/60 pts (38%). AMG 757 serum exposures increased approximately dose proportionally within the evaluated dose range. Conclusions: AMG 757 has an acceptable safety profile at doses up to 100 mg. Responses were rapid and durable. Encouraging anti-tumor activity was seen across dose ranges, with ongoing unconfirmed PR in 5/8 pts (63%) at the highest DL. The study is ongoing; updated data, including response rates and duration of response, will be presented. Clinical trial information: NCT03319940.

Real-world multiomic characterization of small cell lung cancer subtypes to reveal differential expression of clinically relevant biomarkers

8508

Background: The dominant expression of four lineage-defining transcription factors ( ASCL1, NEUROD1, YAP1, or POU2F3) has enabled the classification of small cell lung cancer (SCLC) into four subtypes (SCLC-A/N/Y/P, respectively). Emerging evidence suggests that YAP1 expression is associated with a T-cell inflamed phenotype, and SCLC has significant intra-tumor heterogeneity mediated by MYC-driven activation of NOTCH signaling. We performed a large-scale analysis of real-world SCLC patient samples to examine the expression of clinically relevant biomarkers across SCLC subtypes. Methods: Comprehensive molecular profiling of 437 small cell lung neuroendocrine tumors (including 7.3% high-grade neuroendocrine lung carcinomas) was performed using next-generation DNA sequencing (592-gene panel), RNA sequencing (whole transcriptome), and immunohistochemistry at Caris Life Sciences (Phoenix, AZ). Tumors were stratified into 5 subgroups (SCLC-A/N/Y/P and -mixed) based on the relative expression of the four transcription factors. RNA expression of key genes and previously validated immune signatures (T-cell inflamed, NK cell, and STING pathway signatures) were evaluated across subgroups. Significance was tested by Chi-square, Fisher’s exact test, or Mann-Whitney U test. Results: Median age of the study cohort was 66 years (IQR: 59-72) and 50.6% of patients were female. The majority (67.3%) of samples were derived from metastatic sites. Stratification of tumors by expression resulted in 35.7% SCLC-A, 17.6% SCLC-N, 21.1% SCLC-Y, 6.4% SCLC-P, and 19.2% SCLC-mixed samples. Compared to tumors from metastatic sites, YAP1 expression was significantly increased (p < 0.001) in primary tumors. Amongst the 14 tumors obtained from the CNS, SCLC-N (36%, n = 5) was the most common subtype identified. dMMR/MSI-high (negative MMR protein expression/ ≥46 altered loci per tumor) was rare overall (0.5%, n = 2); TMB (median of 9-10 mut/Mb) was similar between the SCLC subtypes. SCLC-Y was associated with the highest expression of T-cell inflamed, NK cell and STING pathway signatures (p < 0.0001 each). MYC and NOTCH gene expression ( NOTCH1/2/3/4) strongly correlated with YAP1 expression. Analysis of co-mutations revealed that EGFR-sensitizing mutations (L858R and Exon 19 deletions) were recurrent (5.2%, n = 4) in SCLC-N tumors. The expression of SNF11, SSTR2, and MYC varied significantly among SCLC subtypes (p < 0.001 each), with the highest median expression of SNF11 and SSTR2 observed in SCLC-N, while MYC expression was highest in SCLC-P. Conclusions: Our analysis represents the largest real-world dataset of human SCLC tumors profiled by whole transcriptomic sequencing. The differential expression of immune genes and predictive biomarkers across SCLC subtypes may inform therapeutic vulnerabilities for rational and personalized treatment approaches in SCLC.

Trial in progress: Phase 1a/b study of PF-07284890 (brain-penetrant BRAF inhibitor) with/without binimetinib in patients with BRAF V600-mutant solid tumors

TPS3152

Background: BRAF inhibitors have transformed treatment (Tx) for patients (pts) with BRAF V600-mutant cancers, but long-term efficacy is limited by disease progression in the brain, due to poor brain penetration. PF-07284890 is a potent, selective, highly brain-penetrant, small-molecule inhibitor of BRAF V600 mutations. This first in human study will assess the PK, safety, and preliminary clinical activity of PF-07284890, as monotherapy and in combination with binimetinib (MEK inhibitor), in pts with BRAF V600-mutated advanced solid tumors with/without brain metastases. Methods: Phase 1a/1b open-label, multicenter, dose-finding study (NCT04543188). Pts will be ≥18 y with a histologically confirmed advanced/metastatic solid tumor including primary brain tumor (PBT), confirmed BRAF V600 mutation, and presence/absence of brain involvement. Pts will have disease progression despite prior Tx without alternative Tx options. Pts with brain metastasis/PBT > 4 cm and/or symptomatic brain disease will be excluded initially, but allowed based on emerging PK. Phase 1a is a dose escalation study of PF-07284890 (monotherapy and combination). ̃35 pts will be enrolled to determine maximum tolerated dose (MTD) and/or recommended dose for expansion (RDE) of PF-07284890 (monotherapy and combination). Cohorts of 2-4 pts will be treated at each dose level of PF-07284890 until MTD/RDE determination (PF-07284890 starting dose: 50 mg QD; binimetinib 45 mg BID). Bayesian Logistic Regression Model will be used to inform dose level decisions. At least 6 pts each for monotherapy and combination will be treated at MTD/RDE. Phase 1a primary endpoints: Cycle 1 dose-limiting toxicities; MTD/RDE; AEs; lab abnormalities; and dose interruptions, modifications and discontinuations due to AEs. Secondary endpoints include PK parameters and overall response (RECIST; overall and intracranial; RANO for PBT). Phase 1b is a dose expansion and drug-drug interaction study to further evaluate PF-07284890 + binimetinib. Cohorts 1-4 (̃40 pts each) will enroll pts based on tumor type, brain involvement (asymptomatic/symptomatic), and prior Tx. Cohort 5 (̃20 pts) will include pts with any solid tumor including leptomeningeal metastases. Cohort 6 (̃10 pts) will assess the effect of PF-07284890 + binimetinib on CYP3A activity using midazolam as a substrate. Phase 1b primary endpoint: overall response (RECIST; overall and intracranial; RANO for PBT). Secondary endpoints: duration of response; progression-free survival; disease control rate; time to response; overall survival; AEs; lab abnormalities; and dose interruptions, modifications and discontinuations due to AEs; and PK parameters. For both Phase 1a and 1b, Tx will continue until disease progression, unacceptable toxicity or patient refusal. Study began enrolling pts in January 2021 and is ongoing. Clinical trial information: NCT04543188.

Perspectives on under-representation of minority patients (pts) in clinical trials

e18521

Background: About 40% of the US population are from minority groups. Minority pts are under-represented in oncology clinical trials, which limits the applicability of results to the general population and perpetuates poor relationships between healthcare systems and minority communities. This assessment investigated underlying causes of this lack of minority representation in clinical trials and proposes plans to promote diversity. Methods: To better understand the limited inclusion of under-represented pts in oncology clinical trials, 10 specialists in cancer care were selected to provide their perspectives. Specialists were chosen because of their experience enrolling minority pts in clinical trials and met virtually in Dec 2020 via Within3, a secure digital communication platform, to discuss obstacles faced in recruiting minority pts and potential strategies to address these concerns. Specificity and alignment in responses were achieved through software analytics and follow-up queries. Results: The 10 specialists identified as Asian (10%), Black (30%), White (50%), and Hispanic (10%), and began practicing medicine in the 1980s-2010s. All are involved in clinical research and treat a range of minority pts in both urban and suburban settings. Most specialists (8/10) reported treating > 20 minority pts with cancer annually. However, few specialists (2/10) reported that > 20% of their minority pts have enrolled in clinical trials. Specialists agreed that minority pts experience barriers to participation in clinical research, including lack of trust in the healthcare system, materials in their native languages, financial support, minority investigators involved in clinical trials, and accessible study sites. The specialists proposed strategies that could be implemented to increase minority enrollment. These included study sites where minority populations live and industry funded outreach and educational efforts in minority communities. If sites are more accessible, this can reduce time and financial pressures associated with study participation. The specialists recommended that studies be designed to be more supportive of minority populations, specifically regarding inclusion and exclusion criteria and reimbursement of costs. They also advised that increased diversity among clinical researchers and allied personnel may increase the ability of the clinical team to connect with pts and assist in building trust in their communities. Finally, they emphasized the importance of providing informed consent forms and study materials in pts’ native languages. Conclusions: While challenges exist to increasing diversity in oncology clinical studies, a broad consortium of clinical specialists agreed that they can be addressed by community outreach and education, making study sites more accessible, availability of study materials in pts’ native languages, and improving diversity of clinical teams.

A phase I, open-label, dose-escalation trial of BI 764532, a DLL3/CD3 bispecific antibody, in patients (pts) with small cell lung carcinoma (SCLC) or other neuroendocrine neoplasms expressing DLL3

TPS8588

Background: First-line standard of care for pts with metastatic SCLC and neuroendocrine carcinoma (NEC) is platinum-based chemotherapy ± immunotherapy. While the addition of anti-PD1 antibodies has improved outcomes, nearly all pts relapse and prognosis is poor. There is a major unmet need for additional treatment (tx) options. BI 764532 is a delta-like ligand 3 (DLL3)/CD3 T cell engaging bispecific antibody. DLL3 is expressed on the cell surface of many SCLC and NEC tumors, but not on normal cells. In preclinical studies, BI 764532 induced cytotoxicity of DLL3-positive cells and showed anti-tumor activity in animal models. Methods: NCT04429087 is a first-in-human, open-label, dose-escalation trial of BI 764532 in adults with locally advanced/metastatic SCLC, large cell neuroendocrine lung carcinoma, NEC or small cell carcinoma of any other origin. Pts must have failed on or be ineligible for available standard therapies (including ≥1 line of platinum-based chemotherapy). Tumors must be positive for DLL3 expression (archived tissue/in-study fresh biopsy) according to central review. Pts must have ≥1 evaluable lesion (modified RECIST 1.1) outside of CNS and adequate liver, bone marrow and renal organ function. Main exclusion criteria: previous tx with T cell engagers or DLL3-targeted therapies; persistent toxicity from previous tx that has not resolved to ≤ CTCAE grade 1; immunodeficiency or receiving immunosuppressive therapy ≤7 days, prior anti-cancer therapy ≤3 wks/5 half-life periods or extensive field radiotherapy ≤2 wks of first dose of BI 764532. The main objective of phase Ia is to determine the maximum tolerated dose (MTD) or recommended dose for expansion of BI 764532, based on dose-limiting toxicities during the MTD evaluation period. Further objectives are to evaluate safety, tolerability, PK/PD and preliminary efficacy. The phase Ib objectives, endpoints and design will be specified after availability of phase Ia results. The trial will assess ≤3 dosing regimens: Regimen A (fixed iv dose once every 3 wks); Regimen B1 (fixed iv dose once every wk); Regimen B2 (step-in dose[s] followed by fixed-dose weekly doses; optional). Tx will continue until confirmed progressive disease, unacceptable toxicity, other withdrawal criteria or a maximum tx duration of 36 mos, whichever occurs first. For Phase Ia, ̃160 pts will be screened and 110 pts accrued. As of Feb 2021, pts are being recruited and treated in early dose escalation cohorts. Clinical trial information: NCT04429087.

Phase I/II study of nivolumab plus vorolanib in patients with thoracic malignancies: Interim efficacy of the SCLC and primary refractory NSCLC cohorts, and safety data across all cohorts

2578

Background: Combination strategies to improve the efficacy of single agent immune checkpoint inhibitors (ICIs) are increasingly being explored, with one strategy being the addition of vascular endothelial growth factor (VEGF) inhibition. Having shown promise in the treatment of hepatocellular carcinoma and renal cell carcinoma, NCT03583086 is a multi-institutional, phase I/II study of combination vorolanib and nivolumab in both naïve and refractory thoracic tumors that progressed on at least one prior line of platinum-based chemotherapy. Though structurally similar to the tyrosine kinase inhibitor, sunitinib, vorolanib was designed to have a more favorable safety profile with comparable efficacy. Here we present safety data across all cohorts and interim efficacy analyses of the SCLC and NSCLC with primary resistance to ICI-based therapy cohorts, both of which have now completed enrolment. Methods: The maximum tolerated dose determined in phase I was vorolanib 200mg daily and nivolumab 240mg q2 weeks. Phase II uses a two-stage MinMax design across 5 cohorts with objective response rate (ORR) as the primary endpoint: NSCLC (ICI naïve, primary refractory, and acquired resistance), SCLC, and thymic carcinoma. Primary refractory is defined as radiographic progression of disease within 12 weeks of ICI initiation. Results: As of January 2021, 75 patients have been enrolled across all cohorts. Stage 1 of the SCLC and primary refractory NSCLC cohorts have completed accrual at 18 and 15 patients, respectively. In the SCLC cohort, disease-control rate (DCR) was 7% and no objective responses were achieved among 14 evaluable patients. In the primary refractory NSCLC cohort, DCR was 57% and ORR 7% (1 partial response) among 14 evaluable patients. A total of 140 treatment-related adverse events (TRAEs) have been reported, 13 (9%) were grade 3 and there were no grade 4/5 events. Fatigue (9%), nausea (6%), diarrhea (6%), ALT elevation (5%), and AST elevation (5%) were the most common all grade TRAEs. The most common grade 3 TRAEs were ALT elevation and hypertension. Conclusions: This therapeutic strategy of nivolumab plus vorolanib appears to be a well-tolerated combination with a manageable safety profile. Adding VEGF inhibition may offer additional disease control in the setting of NSCLC with primary resistance to ICIs, but neither the SCLC or primary refractory NSCLC cohorts achieved the pre-determined target number of objective responses for progression to stage 2 of the study. Enrolment in the other 3 cohorts as well as exploratory correlatives are ongoing. Clinical trial information: NCT03583086.

YAP1 transcription factor expression to define subsets of cancers with T-cell inflamed phenotype in a pan-tumor analysis across 33 tumor types

2610

Background: Immune checkpoint blockade (ICB) has become an established treatment option for the majority of solid tumors. PD-L1 expression, tumor mutation burden (TMB) and mismatch repair (MMR) deficiency are established but suboptimal predictive markers to select patients for ICB therapy. The identification of better predictive biomarkers to complement existing biomarkers is an area of need. We previously identified Yes Associated Protein 1 (YAP1) gene expression as a marker of inflamed tumor phenotype in small cell lung cancer. We sought to elucidate the role of YAP1 as a tumor agnostic biomarker of inflamed tumor phenotype. Methods: We obtained the publicly available TCGA normalized RSEM expression data (version dated September 29, 2019) from the GDC legacy archive (https://portal.gdc.cancer.gov/legacy-archive) for this analysis. We used the shinySISPA method ( https://bbisr.shinyapps.winship.emory.edu/shinySISPA/ ) to classify the primary tumor samples into YAP1 high or low on the basis of the normalized expression profile for YAP1 gene. The T-cell–inflamed gene expression profile score for each sample was calculated as weighted sum of the normalized expression values of the 18 genes ( PSMB10, HLA-DQA1, HLA-DRB1, CMKLR1, HLA-E, NKG7, CD8A, CCL5, CXCL9, CD27, CXCR6, IDO1, STAT1, TIGIT, LAG3, CD274, PDCD1LG2, CD276) as originally published in the Patent filed under “WO201609437” and validated as a predictor of clinical efficacy in patients treated with anti PD1 immunotherapy drug, pembrolizumab. Results: A total of 11283 samples from 33 different histologic tumor types contained in the TCGA database were included in this analysis. A small but meaningful subset of cases 271 (2%) were classified as YAP1 high with a wide range in proportion of YAP1 high tumors of 0.67% to 12.09% across the 33 histologic tumor types. Adrenocortical, cholangiocarcinoma, chromophobe RCC, DLBCL, and mesothelioma had a high rate of YAP1 high tumors (> 10% of cases). Overall trend showed a higher median interferon gamma GEP score in YAP1 high versus YAP1 low tumors with a GEP score of 11.2 vs. 10.7 respectively. A minority of histologic tumor subtypes (HNSCC, clear cell RCC, sarcoma, uterine carcinosarcoma, testicular GCT, melanoma, mesothelioma and ovarian cancer) showed a reverse trend of lower GEP score in association with YAP1 high status. Ongoing validation of these findings in an independent cohort of clinical samples and correlation of YAP1 status with other predictive biomarkers (TMB, PD-L1 and MSS status) will be presented at the meeting. Conclusions: YAP1 is highly expressed in a small but meaningful subsets of cancers and is associated with the inflamed phenotype in the majority of cancers. YAP1 expression is most common in rarer tumor types and in histologic types where currently available biomarkers have not been shown to predict the benefit of ICB.

Veliparib in Combination with Carboplatin and Etoposide in Patients with Treatment-Naïve Extensive-Stage Small Cell Lung Cancer: A Phase 2 Randomized Study

PURPOSE

This study investigated the efficacy and safety of oral PARP inhibitor veliparib, plus carboplatin and etoposide in patients with treatment-naïve, extensive-stage small cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

Patients were randomized 1:1:1 to veliparib [240 mg twice daily (BID) for 14 days] plus chemotherapy followed by veliparib maintenance (400 mg BID; veliparib throughout), veliparib plus chemotherapy followed by placebo (veliparib combination only), or placebo plus chemotherapy followed by placebo (control). Patients received 4-6 cycles of combination therapy, then maintenance until unacceptable toxicity/progression. The primary endpoint was progression-free survival (PFS) with veliparib throughout versus control.

RESULTS

Overall (N = 181), PFS was improved with veliparib throughout versus control [hazard ratio (HR), 0.67; 80% confidence interval (CI), 0.50-0.88; P = 0.059]; median PFS was 5.8 and 5.6 months, respectively. There was a trend toward improved PFS with veliparib throughout versus control in SLFN11-positive patients (HR, 0.6; 80% CI, 0.36-0.97). Median overall survival (OS) was 10.1 versus 12.4 months in the veliparib throughout and control arms, respectively (HR, 1.43; 80% CI, 1.09-1.88). Grade 3/4 adverse events were experienced by 82%, 88%, and 68% of patients in the veliparib throughout, veliparib combination-only and control arms, most commonly hematologic.

CONCLUSIONS

Veliparib plus platinum chemotherapy followed by veliparib maintenance demonstrated improved PFS as first-line treatment for ED-SCLC with an acceptable safety profile, but there was no corresponding benefit in OS. Further investigation is warranted to define the role of biomarkers in this setting.

Phase 2 Study of Talazoparib in Patients With Homologous Recombination Repair-Deficient Squamous Cell Lung Cancer: Lung-MAP Substudy S1400G

PURPOSE

This signal finding study (S1400G) was designed to evaluate the efficacy of talazoparib in advanced stage squamous cell lung cancer harboring homologous recombination repair deficiency.

PATIENTS AND METHODS

The full eligible population (FEP) had tumors with a deleterious mutation in any of the study-defined homologous recombination repair genes and without prior exposure to a PARP inhibitor. The primary analysis population (PAP) is a subset of FEP with alteration in ATM, ATR, BRCA1, BRCA2, or PALB2. Treatment consisted of talazoparib 1 mg daily continuously in 21-day cycles. A 2-stage design with exact 93% power and 1-sided 0.07 type I error required enrollment of 40 patients in the PAP in order to rule out an overall response rate (ORR) of 15% or less if the true ORR is ≥ 35%.

RESULTS

The study enrolled 47 patients in the FEP, of whom 24 were in the PAP. The median age for the FEP was 66.7 years; 83% were male and 85% white. ORR in the PAP was 4% (95% confidence interval [CI], 0, 21) with disease control rate of 54% (95% CI, 33, 74). Median progression-free survival and overall survival were 2.4 months (95% CI, 1.5-2.8) and 5.2 months (95% CI, 4.0-10), respectively. In the FEP, ORR was 11% (95% CI, 3.6, 23), the disease control rate was 51% (95% CI, 36, 66), and the median duration of response was 1.8 months (95% CI, 1.3, 4.2). Median progression-free and overall survival were 2.5 months and 5.7 months, respectively.

CONCLUSIONS

S1400G failed to show sufficient level of efficacy for single agent talazoparib in a biomarker defined subset of squamous lung cancer with homologous recombination repair deficiency.

Nivolumab and Ipilimumab as Maintenance Therapy in Extensive-Disease Small-Cell Lung Cancer: CheckMate 451

In extensive-disease small-cell lung cancer (ED-SCLC), response rates to first-line platinum-based chemotherapy are robust, but responses lack durability. CheckMate 451, a double-blind phase III trial, evaluated nivolumab plus ipilimumab and nivolumab monotherapy as maintenance therapy following first-line chemotherapy for ED-SCLC.

Impact of lung metastases on overall survival in the phase 3 SELECT study of lenvatinib in patients with radioiodine-refractory differentiated thyroid cancer

BACKGROUND

Lung metastases may worsen overall survival (OS) in patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC). We investigated (post hoc) the impact of lung metastases on survival in SELECT (a phase 3 study).

PATIENTS AND METHODS

392 patients with RR-DTC were randomised 2:1 to lenvatinib 24 mg daily (n = 261) or placebo (n = 131). Placebo-treated patients could crossover to open-label lenvatinib following progression. Patients were grouped by size of baseline lung metastases. Safety/efficacy outcomes, collated by these lung-metastases subgroups, were generated.

RESULTS

Lenvatinib-treated population distributions per baseline lung metastases subgroup were any lung metastases (target/nontarget lesions; n = 226), and by maximum size of target lung lesions ≥1.0 cm (n = 199), ≥1.5 cm (n = 150), ≥2.0 cm (n = 94) and <2.0 cm (n = 105). In patients with any lung metastases, no statistically significant difference in OS was observed between treatment arms (HR: 0.76; 95% CI: 0.57-1.01; P = 0.0549). Median OS for lung metastases of ≥1.0 cm was 44.7 months (lenvatinib) versus 33.1 months (placebo) (HR: 0.63; 95% CI: 0.47-0.85; P = 0.0025). OS was significantly prolonged with lenvatinib versus placebo among patients with lung metastases of ≥1.0 cm, ≥1.5 cm, ≥2.0 cm and <2.0 cm; median OS was shorter in the ≥2.0 cm subgroup (lenvatinib: 34.7 months) versus other subgroups (lenvatinib: 44.1-49.2 months). Multivariate analysis demonstrated lenvatinib significantly prolonged OS in patients with lung metastases of ≥1.0 cm after adjustment for baseline characteristics.

CONCLUSIONS

Lenvatinib treatment resulted in longer OS in patients with lung metastases of ≥1.0 cm versus placebo (even with the 89% crossover rate). Early initiation of lenvatinib may improve outcomes in patients with RR-DTC and lung metastases of ≥1.0 cm.

SOURCE STUDY REGISTRATION

ClinicalTrials.Gov Identifier: NCT01321554.

Trilaciclib dose selection: an integrated pharmacokinetic and pharmacodynamic analysis of preclinical data and Phase Ib/IIa studies in patients with extensive-stage small cell lung cancer

Purpose

Trilaciclib is a first-in-class CDK4/6 inhibitor that transiently arrests hematopoietic stem and progenitor cells (HSPCs) in the G1 phase of the cell cycle to preserve them from chemotherapy-induced damage (myelopreservation). We report integrated analyses of preclinical and clinical data that informed selection of the recommended Phase II dose (RP2D) used in trilaciclib trials in extensive-stage small cell lung cancer (ES-SCLC).

Methods

A semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model developed from preclinical data guided selection of an optimal dose for G1 bone marrow arrest in a first-in-human Phase I study (G1T28-1-01). PK, PD, safety, and efficacy data from G1T28-1-01 and two Phase Ib/IIa studies (G1T28-02/-03) in ES-SCLC were analyzed to support RP2D selection.

Results

Model simulation of bone marrow arrest based on preclinical data predicted that a ≥ 192 mg/m² dose would induce a 40–50% decrease in total bone marrow proliferation in humans and almost 100% cell cycle arrest of cycling HSPCs. Consistent with this model, analysis of bone marrow aspirates in healthy volunteers after trilaciclib 192 mg/m² administration demonstrated almost 100% G1 arrest in HSPCs and 40% decrease in total bone marrow proliferation, with minimal toxicity. G1T28-02/-03 reported similar PK parameters with trilaciclib 200 mg/m² but slightly lower exposures than expected compared with healthy volunteers; consequently, 240 and 280 mg/m² doses were also tested to match healthy volunteer exposures. Based on PK and relevant safety data, 240 mg/m² was selected as the RP2D, which was also favored by myelopreservation endpoints in G1T28-02/-03.

Conclusion

Integrated PK/PD, safety, and efficacy data support 240 mg/m² as the RP2D for trilaciclib.

ClinicalTrials.gov Identifiers

NCT02243150; NCT02499770; NCT02514447.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04239-9.

Downregulation of death receptor 4 is tightly associated with positive response of EGFR mutant lung cancer to EGFR-targeted therapy and improved prognosis

Death receptor 4 (DR4), a cell surface receptor, mediates apoptosis or induces inflammatory cytokine secretion upon binding to its ligand depending on cell contexts. Its prognostic impact in lung cancer and connection between EGFR-targeted therapy and DR4 modulation has not been reported and thus was the focus of this study. Methods: Intracellular protein alterations were measured by Western blotting. Cell surface protein was detected with antibody staining and flow cytometry. mRNA expression was monitored with qRT-PCR. Gene transactivation was analyzed with promoter reporter assay. Drug dynamic effects in vivo were evaluated using xenografts. Gene modulations were achieved with gene overexpression and knockdown. Proteins in human archived tissues were stained with immunohistochemistry. Results: EGFR inhibitors (e.g., osimertinib) decreased DR4 levels only in EGFR mutant NSCLC cells and tumors, being tightly associated with induction of apoptosis. This modulation was lost once cells became resistant to these inhibitors. Increased levels of DR4 were detected in cell lines with acquired osimertinib resistance and in NSCLC tissues relapsed from EGFR-targeted therapy. DR4 knockdown induced apoptosis and augmented apoptosis when combined with osimertinib in both sensitive and resistant cell lines, whereas enforced DR4 expression significantly attenuated osimertinib-induced apoptosis. Mechanistically, osimertinib induced MARCH8-mediated DR4 proteasomal degradation and suppressed MEK/ERK/AP-1-dependent DR4 transcription, resulting in DR4 downregulation. Moreover, we found that DR4 positive expression in human lung adenocarcinoma was significantly associated with poor patient survival. Conclusions: Collectively, we suggest that DR4 downregulation is coupled to therapeutic efficacy of EGFR-targeted therapy and predicts improved prognosis, revealing a previously undiscovered connection between EGFR-targeted therapy and DR4 modulation.

A Call to Action: Dismantling Racial Injustices in Preclinical Research and Clinical Care of Black Patients Living with Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive disease with dismal survival rates and limited therapeutic options. SCLC development is strongly associated with exposure to tobacco carcinogens. However, additional genetic and environmental risk factors that contribute to SCLC pathogenesis are beginning to emerge. Here, we specifically assess disparities pertaining to SCLC in Black populations. In contrast to non-small cell lung cancer, preliminary data suggest that Black individuals may actually be at a lower risk of developing SCLC relative to white individuals. This difference remains unexplained but urgently needs to be verified in larger data sets, because it could provide important new insights and approaches to understanding this recalcitrant tumor. Importantly, little biological information exists on SCLC in Black individuals, and few patient-derived preclinical SCLC models from diverse ancestries are available in the laboratory. Unfortunately, we note strikingly low numbers of Black participants in clinical trials testing new treatments for SCLC. Evidence further indicates that care for patients with SCLC may vary between communities with a large fraction of Black patients and those without. Together, these observations underscore the need to better investigate genetic, environmental, and socioeconomic factors associated with SCLC development, preclinical research, clinical care, and outcomes.

Phase I expansion study of P-cadherin-targeted 90Y-FF-21101 antibody in advanced chemorefractory colorectal and pancreatic-biliary cancers

78

Background: Overexpression of the cell-cell adhesion protein P-cadherin has been associated with a more aggressive cancer cell phenotype, cancer stem cell properties, tumor invasion and metastasis. We determined the safety and recommended Phase II dose of the yttrium-labeled P-cadherin-targeted 90Y-FF-21101 monoclonal antibody (mAb) in patients (pts) with advanced tumors, and focused our expansion study in advanced colorectal (CRC) and pancreatic-biliary cancers (non-CRC tumors). We report the safety, efficacy, and correlative pharmacokinetics (PK)/pharmacodynamics (PD) in this cohort. Methods: Pts enrolled must have progressed on all standard therapies. 25 mCi/m2 (8 mCi/mg mAb) 90Y-FF-21101 was administered intravenously every 12 weeks (wks) until disease progression or unacceptable toxicity. Disease response was assessed based on RECIST v1.1 every 8 wks (1 cycle = 28 days). Serum mAb PK, existence of anti-drug antibodies (ADA) and tumor P-cadherin expression were also evaluated. Results: 31 pts [mean age 63 (range, 39-89); 14F/17M; median number of prior therapies, 3 (range, 1-11)] with CRC (18) and non-CRC tumors [pancreatic (8), cholangiocarcinoma (3), duodenal (2)] received a median of 1 (range, 1-2) dose of 90Y-FF-21101. Median duration on study was 8.1 (3.9 – 27) wks (CRC) and 8 (1.1-17.1) wks (pancreatic-biliary). Myelosuppression was the most common treatment-related adverse event [thrombocytopenia (87%; Grade (Gr) 3/4 in 45%), lymphopenia (74%; Gr 3/4 in 61%), anemia (52%; Gr 3/4 in 13%), leukopenia (32%; Gr 3/4 in 16%)], in addition to fatigue (68%, 1 Gr 3) and nausea (39%, 1 Gr 3). Three pts required dose reduction to 20 mCi/m2 with subsequent infusion after Gr 3/4 thrombocytopenia [(pancreatic (2), CRC (1)]. The clinical benefit rate in pts with CRC based on stable disease (SD) for ≥8 wks is 43.8% (7/16 pts), with a median PFS of 8.1 wks and OS of 27 wks [median PFS, 7.9 wks; OS, 17.1 wks in non-CRC]. Longer-term SD was maintained in 2 pts with CRC for 17-24 wks; one continues on treatment. Enrollment is ongoing in the non-CRC cohort. FF-21101 has a mean t1/2 of approximately 65 hours, and post-treatment ADA titers have been observed in < 5% of pts. Tumor P-cadherin expression analysis by IHC demonstrated H-scores > 150 in 88% (14/16) of CRC pts, 75% (9/12) for non-CRC; 2 CRC pts with SD ≥17 wks had H-scores ≥190. Conclusions: 90Y-FF-21101 administered every 12 wks demonstrated expected toxicities and has been generally well-tolerated, with preliminary evidence of benefit demonstrated in heavily pre-treated pts with advanced CRC. The optimal dose and schedule for this radioimmunotherapeutic will continue to be explored, along with pre-treatment P-cadherin expression as a predictive biomarker for disease response. Clinical trial information: NCT02454010.

Optimum health and inhibition of cancer progression by microbiome and resveratrol

Resveratrol (RES) is a naturally occurring polyphenol found in fruits, green leafy vegetables, and peanuts. This versatile compound, which has potent regenerative, anti-oxidative, and cancer-fighting properties, is produced in plants, particularly in response to stress stimuli. By various mechanisms, including regulation of genes and proteins, RES inhibits the growth of pathogenic bacteria and the development of cancers. The gut has a prominent role in nutrient assimilation, metabolism, immunity, and cancer regression, and the endogenous microbiome protects the host from invasive bacteria that facilitate the progression of various diseases. Short-chain fatty acids (SFCAs) are the byproducts of microbial fermentation in the gastrointestinal tract. Native microflora regulates internal homeostasis, influence the activity of host immune cells, and regress some cancers via the action of SCFAs produced from a plant-based diet. This review shows the relevance of dietary constituents and gut microbial activity in ensuring optimal health of the host.

Myelopreservation with Trilaciclib in Patients Receiving Topotecan for Small Cell Lung Cancer: Results from a Randomized, Double-Blind, Placebo-Controlled Phase II Study

INTRODUCTION

Multilineage myelosuppression is an acute toxicity of cytotoxic chemotherapy, resulting in serious complications and dose modifications. Current therapies are lineage specific and administered after chemotherapy damage has occurred. Trilaciclib is a cyclin-dependent kinase 4/6 inhibitor that is administered prior to chemotherapy to preserve hematopoietic stem and progenitor cells and immune system function during chemotherapy (myelopreservation).

METHODS

In this randomized, double-blind, placebo-controlled phase II trial, patients with previously treated extensive-stage small cell lung cancer (ES-SCLC) were randomized to receive intravenous trilaciclib 240 mg/m2 or placebo before topotecan 1.5 mg/m2 on days 1-5 of each 21-day cycle. Primary endpoints were duration of severe neutropenia (DSN) in cycle 1 and occurrence of severe neutropenia (SN). Additional endpoints were prespecified to further assess the effect of trilaciclib on myelopreservation, safety, patient-reported outcomes (PROs), and antitumor efficacy.

RESULTS

Thirty-two patients received trilaciclib, and 29 patients received placebo. Compared with placebo, administration of trilaciclib prior to topotecan resulted in statistically significant and clinically meaningful decreases in DSN in cycle 1 (mean [standard deviation] 2 [3.9] versus 7 [6.2] days; adjusted one-sided P < 0.0001) and occurrence of SN (40.6% versus 75.9%; adjusted one-sided P = 0.016), with numerical improvements in additional neutrophil, red blood cell, and platelet measures. Patients receiving trilaciclib had fewer grade ≥ 3 hematologic adverse events than patients receiving placebo, particularly neutropenia (75.0% versus 85.7%) and anemia (28.1% versus 60.7%). Myelopreservation benefits extended to improvements in PROs, specifically in those related to fatigue. Antitumor efficacy was comparable between treatment arms.

CONCLUSIONS

Compared with placebo, the addition of trilaciclib prior to topotecan for the treatment of patients with previously treated ES-SCLC improves the patient experience of receiving chemotherapy, as demonstrated by a reduction in chemotherapy-induced myelosuppression, improved safety profile, improved quality of life and no detrimental effects on antitumor efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02514447.

Durvalumab and tremelimumab with or without stereotactic body radiation therapy in relapsed small cell lung cancer: a randomized phase II study

Background

Immune checkpoint blockade (ICB) targeting programmed cell death protein 1 and cytotoxic T lymphocyte-associated protein 4 has achieved modest clinical activity as salvage therapy in relapsed small cell lung cancer (SCLC). We conducted this signal-finding study to assess the efficacy of ICB with or without radiation in relapsed SCLC.

Methods

Patients with relapsed SCLC and ≤2 previous lines of therapy were randomized to (1) arm A: durvalumab (D) 1500 mg/tremelimumab (T) 75 mg (intravenously every 4 weeks without stereotactic body radiation therapy (SBRT)) or (2) arm B: immune-sensitizing SBRT to one selected tumor site (9 Gy × 3 fractions) followed by D/T. Treatment continued until progression or a maximum of 12 months. The co-primary endpoints of the study were overall response rate (ORR) and progression-free survival (PFS). We evaluated circulating lymphocyte repertoire in serial peripheral blood samples and tumor infiltrating lymphocytes (TILs) from on-treatment biopsies as pharmacodynamic markers.

Results

Eighteen patients were randomized to arms A and B (n=9 each): median age 70 years; 41.2% women. The median PFS and ORR were 2.1 months and 0% in arm A and 3.3 months and 28.6% in arm B. The median overall survival (OS) was 2.8 months in arm A and 5.7 months in arm B (p=0.3772). Pooled efficacy of D/T±SBRT in 15 Response evaluation criteria in solid tumors (RECIST) evaluable patients across both arms showed the best ORR in terms of partial response in 13.3%, stable disease in 26.6% and progressive disease in 60.0%; the overall median PFS and OS were 2.76 and 3.9 months. The most common adverse events were grade 1 fatigue (66%) and grade 1 elevated amylase (56%) in arm A, and grade 1 fatigue (56%) and pain (44%) in arm B. There was a significant increase in activated CD8(+)ICOS+ T cells (p=0.048) and a reduction in naïve T cells (p=0.0454) in peripheral blood following treatment, along with a significant amount of activated CD8+ICOS+ T cells in TILs from responders.

Conclusions

The D/T combination with and without SBRT was safe but did not show sufficient efficacy signal in relapsed SCLC. Changes in peripheral blood lymphocyte and TILs were consistent with an immunologic response.

Trial registration number NCT02701400.

Effects of Rovalpituzumab Tesirine on Ventricular Repolarization in Patients With Small-Cell Lung Cancer

Small cell lung cancer (SCLC) is a leading cause of cancer death worldwide, with few treatment options. Rovalpituzumab tesirine (Rova‐T) is an antibody‐drug conjugate that targets delta‐like 3 on SCLC cells to deliver a cytotoxic payload directly to tumor cells. In this study, the cardiac safety profile of Rova‐T was assessed by evaluating changes in QT interval, electrocardiogram (ECG) waveform, heart rate, and proarrhythmic adverse events (AEs) after treatment with Rova‐T in patients with previously treated extensive‐stage SCLC. Patients underwent ECG monitoring for 2 weeks after each of 2 i.v. infusions of 0.3 mg/kg Rova‐T over 30 minutes, administered 6 weeks apart. Forty‐six patients received at least one dose of Rova‐T. At the geometric mean Rova‐T maximum serum concentration of 7,940 ng/mL, ECG monitoring showed no significant changes in the Fridericia‐corrected QT (QTcF) interval; the upper limit of the 2‐sided 90% confidence interval did not exceed 10 msec for any time point. There were no clinically significant changes in QRS or PR intervals, ECG waveforms, or heart rate after Rova‐T administration. All patients experienced a treatment‐emergent AE (TEAE); 78% had a grade ≥ 3 TEAE, 59% had a serious TEAE, and 41% had a cardiac‐related TEAE. The TEAEs that might signal proarrhythmia tendencies were uncommon. Confirmed partial responses were observed in 24% of patients. Based on the evaluation of ECG data collected in this study from patients treated with Rova‐T at 0.3 mg/kg i.v. administered every 6 weeks, a QTcF effect of clinical concern can be excluded.

Benefits and limitations of real-world evidence: lessons from EGFR mutation-positive non-small-cell lung cancer

While randomized controlled trials (RCTs) are the gold standard for evidence-based medicine, they do not always reflect real-world patient populations, limiting their generalizability and external validity. Real-world evidence (RWE), generated during routine clinical practice, is increasingly important in determining effectiveness outside of the tightly controlled conditions of RCTs, and is now recognized by regulatory bodies as a valuable complement to RCTs. Consequently, it is increasingly important for physicians to understand how RWE data can be used alongside clinical trial data. Here, we discuss the different types of real-world observational studies, outline the benefits and limitations of RWE, and, using examples from EGFR mutation-positive non-small-cell lung cancer, outline how RWE can be used to help inform treatment decisions.

YAP1 Expression in SCLC Defines a Distinct Subtype With T-cell-Inflamed Phenotype

INTRODUCTION

The clinical and biological significance of the newly described SCLC subtypes, SCLC-A, SCLC-N, SCLC-Y, and SCLC-P, defined by the dominant expression of transcription factors ASCL1, NeuroD1, YAP1, and POU2F3, respectively, remain to be established.

METHODS

We generated new RNA sequencing expression data from a discovery set of 59 archival tumor samples of neuroendocrine tumors and new protein expression data by immunohistochemistry in 99 SCLC cases. We validated the findings from this discovery set in two independent validation sets consisting of RNA sequencing data generated from 51 SCLC cell lines and 81 primary human SCLC samples.

RESULTS

We successfully classified 71.8% of SCLC and 18.5% of carcinoid cases in our discovery set into one of the four SCLC subtypes. Gene set enrichment analysis for differentially expressed genes between the SCLC survival outliers (top and bottom deciles) matched for clinically relevant prognostic factors revealed substantial up-regulation of interferon-γ response genes in long-term survivors. The SCLC-Y subtype was associated with high expression of interferon-γ response genes, highest weighted score on a validated 18-gene T-cell-inflamed gene expression profile score, and high expression of HLA and T-cell receptor genes. YAP1 protein expression was more prevalent and more intensely expressed in limited-stage versus extensive-stage SCLC (30.6% versus 8.5%; p = 0.0058) indicating good prognosis for the SCLC-Y subtype. We replicated the inflamed phenotype of SCLC-Y in the two independent validation data sets from the SCLC cell lines and tumor samples.

CONCLUSIONS

SCLC subtyping using transcriptional signaling holds clinical relevance with the inflamed phenotype associated with the SCLC-Y subset.

An update on the immune landscape in lung and head and neck cancers

Immunotherapy has dramatically changed the treatment landscape for patients with cancer. Programmed death-ligand 1/programmed death-1 checkpoint inhibitors have been in the forefront of this clinical revolution. Currently, there are 6 US Food and Drug Administration-approved checkpoint inhibitors for approximately 18 different histologic types of cancer. Lung cancer and head and neck squamous cell carcinoma (HNSCC) are 2 diseases that have led the way in the development of immunotherapy. Atezolizumab, durvalumab, nivolumab, and pembrolizumab are all currently used as part of standard-of-care treatment for different stages of lung cancer. Similarly, nivolumab and pembrolizumab have US regulatory approval as treatment for advanced metastatic HNSCC. This is significant because lung cancer represents the most common and most fatal cancer globally, and HNSCC is the sixth most common. Currently, most of the approvals for the use of immunotherapy agents are for patients diagnosed in the metastatic setting. However, research is ongoing to evaluate these drugs in earlier stage disease. There is plausible biological rationale to expect that pharmacologic activation of the immune system will be effective for early-stage and smaller tumors. In addition, selecting patients who are more likely to respond to immunotherapy and understanding why resistance develops are crucial areas of ongoing research. The objective of this review was to provide an overview of the current immune landscape and future directions in lung cancer and HNSCC.