Tumor PD-L1 Research Articles

The influence of PD-L1 expression levels on the efficacy of combination therapy in thymic epithelial tumors.

The significant expression of PD-L1 in thymic epithelial tumors (TETs) has been confirmed, and immunotherapy and its combination therapy have been effective in TETs. However, there is no present evidence that the expression levels of PD-L1 affects the efficacy of combination therapy. Our study aimed to shed light on this relationship. Patients with thymic epithelial tumors (TETs) from multicenter hospitals were retrospectively identified. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAEs) in 22 patients were included. We divided the patients the 22 patients with PD-L1 test into three levels (high expression, low expression and no expression) and analyzed the relationship between the levels of PD-L1 expression and the efficacy of combination therapy. Combination therapy showed an effective benefit in 22 patients with TETs, the median PFS (mPFS) was 16 months (95% CI: 8.5-23.5) and the median OS (mOS) was 38 months (95% CI: 21.5-54.5). Cox-regressive analysis found whether PD-L1 expression affected the PFS of patients (p = 0.017). Among the patients with PD-L1 expression, the levels of expression were correlated with curative effect (Kruskal-Wallis test, PFS: P = 0.012; OS: P = 0.01), and high expression group was along with better efficacy than low expression (Wilcoxon test, P = 0.01). Moreover, in 17 patients treated with immunotherapy combined with chemotherapy, the expression of PD-L1 was also associated with efficacy (Kruskal-Wallis test, p = 0.021). PD-L1 expression affects the PFS of patients. High expression of PD-L1 patients with TETs responded better to combination therapy, which could provide a therapeutic option in clinic. Besides, other targeted treatments should be considered.

Novel Combinations of Immunotherapies or DNA Damage Repair Inhibitors in Platinum-Refractory Extensive-Stage Small Cell Lung Cancer: The Phase II BALTIC Study.

The phase II, multiarm, signal-searching BALTIC study (NCT02937818) assessed novel treatment combinations for platinum-refractory/resistant extensive-stage small cell lung cancer (ES-SCLC). Patients with ES-SCLC with progressive disease during or within 90 days of completing first-line platinum-based chemotherapy received one of three regimens: durvalumab plus tremelimumab followed by durvalumab monotherapy (arm A), adavosertib plus carboplatin (arm B), or ceralasertib plus olaparib (arm C). The primary endpoint was the objective response rate. Prespecified exploratory biomarker analyses were conducted in arms A and C. In arm A (n = 41), arm B (n = 10), and arm C (n = 21), the confirmed objective response rates were 7.3%, 0%, and 4.8%, respectively. Safety profiles in all arms were consistent with those of the individual drugs. In arm A, patients with PD-L1 expression (tumor cells or immune cells) ≥1% seemed to have a greater likelihood of achieving disease control with durvalumab plus tremelimumab than those with PD-L1 (tumor cells and immune cells) <1%, and lower baseline ctDNA and reduction in the on-treatment ctDNA level were both associated with longer overall survival. Among patients treated with ceralasertib plus olaparib in arm C, specific immune response-relevant circulating chemokines and cytokines were identified as early biomarkers of survival and pharmacodynamic biomarkers. In BALTIC, all combination regimens demonstrated tolerable safety profiles, but antitumor activity was limited in refractory/resistant ES-SCLC. Among patients treated with durvalumab plus tremelimumab, an association of on-treatment reduction in ctDNA with longer overall survival suggests the potential use of ctDNA as a surrogate of treatment response, warranting further investigation.

Lifileucel, an Autologous Tumor-Infiltrating Lymphocyte Monotherapy, in Patients with Advanced Non-Small Cell Lung Cancer Resistant to Immune Checkpoint Inhibitors.

In this phase 2 multicenter study, we evaluated the efficacy and safety of lifileucel (LN-145), an autologous tumor-infiltrating lymphocyte cell therapy, in patients with metastatic non-small cell lung cancer (mNSCLC) who had received prior immunotherapy and progressed on their most recent therapy. The median number of prior systemic therapies was 2 (range, 1-6). Lifileucel was successfully manufactured using tumor tissue from different anatomic sites, predominantly lung. The objective response rate was 21.4% (6/28). Responses occurred in tumors with profiles typically resistant to immunotherapy, such as PD-L1-negative, low tumor mutational burden, and STK11 mutation. Two responses were ongoing at the time of data cutoff, including one complete metabolic response in a PD-L1-negative tumor. Adverse events were generally as expected and manageable. Two patients died of treatment-emergent adverse events: cardiac failure and multiple organ failure. Lifileucel is a potential treatment option for patients with mNSCLC refractory to prior therapy. Significance: Autologous tumor-infiltrating lymphocyte therapy lifileucel was administered to 28 patients with heavily pretreated metastatic non-small cell lung cancer (mNSCLC). Responses were observed in patients with driver mutations, and various tumor mutational burdens and PD-L1 expression, potentially addressing an unmet medical need in patients with mNSCLC refractory to prior therapy. See related commentary by Lotze et al., p. 1366.

HHLA2: An Emerging Immune Checkpoint for Cancer Immunotherapy.

HHLA2, a member of the B7 family of co-signaling molecules, is aberrantly expressed in various human cancers and has emerged as a promising target for cancer immunotherapy. It exhibits a unique structure and tissue distribution pattern compared to other B7 family members, where its expression is regulated by the complex physiological and tumor microenvironment. HHLA2 plays a crucial but contradictory role in immune modulation, and is thereby associated with heterogeneous prognostic implications across different cancer types. It interacts with two distinct receptors: TMIGD2, which is predominantly expressed on naïve T and NK cells to deliver co-stimulatory signals to T cells and NK cells; and KIR3DL3, which is prevalent on terminally differentiated T and CD56dim CD16+ NK cells to transmit inhibitory signals. The expression dynamics of these receptors on immune cells contribute to the maintenance of immune response homeostasis. Therapeutic strategies targeting the HHLA2 immune checkpoint aim to selectively inhibit the immunosuppressive HHLA2-KIR3DL3 pathway while preserving the HHLA2-TMIGD2 signaling. Several anti-HHLA2 and anti-KIR3DL3 antibodies are currently under investigation in early clinical trials, building upon encouraging results observed in humanized mouse models. Notably, the non-overlapping expression of HHLA2 and PD-L1 in tumors suggests potential synergistic benefits of combining HHLA2-KIR3DL3 targeted therapies with PD-1/PD-L1 blockade or anti-CTLA-4 to augment antitumor activity.

Application of 99mTc-Labeled WL12 Peptides as a Tumor PD-L1-Targeted SPECT Imaging Agent: Kit Formulation, Preclinical Evaluation, and Study on the Influence of Coligands.

With the development of PD-1/PD-L1 immune checkpoint inhibitor therapy, the ability to monitor PD-L1 expression in the tumor microenvironment is important for guiding therapy. This study was performed to develop a novel radiotracer with optimal pharmacokinetic properties to reflect PD-L1 expression in vivo via single-photon emission computed tomography (SPECT) imaging. [99mTc]Tc-HYNIC-WL12-tricine/M (M = TPPTS, PDA, ISONIC, 4-PSA) complexes with high radiochemical purity (>97%) and suitable molar activity (from 100.5 GBq/μmol to 300 GBq/μmol) were prepared through a kit preparation process. All 99mTc-labeled HYNIC-WL12 radiotracers displayed good in vitro stability for 4 h. The affinity and specificity of the four radiotracers for PD-L1 were demonstrated both in vitro and in vivo. The results of biodistribution studies displayed that the pharmacokinetics of the 99mTc-HYNIC-conjugated radiotracers were significantly influenced by the coligands of the radiotracers. Among them, [99mTc]Tc-HYNIC-WL12-tricine/ISONIC exhibited the optimal pharmacokinetic properties (t1/2α = 8.55 min, t1/2β = 54.05 min), including the fastest clearance in nontarget tissues, highest tumor-to-background contrast (e.g., tumor-to-muscle ratio, tumor-to-blood ratio: 40.42 ± 1.59, 14.72 ± 2.77 at 4 h p.i., respectively), and the lowest estimated radiation absorbed dose, highlighting its potential as a clinical SPECT imaging probe for tumor PD-L1 detection.

Tumor-intrinsic IFNα and CXCL10 are critical for immunotherapeutic efficacy by recruiting and activating T lymphocytes in tumor microenvironment

Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10–30% of patients with various cancers. Literature has demonstrated that a “hot tumor” which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a “cold tumor.” This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8+ T cells to become “hot tumor.” In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4+ T, and CD8+ T cell activation. Particularly, we found that CD8+ T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8+ T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8+ T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8+ T cells in the tumor microenvironment, exhibiting “hot tumor” characteristic of sensitizing αPD-L1 immunotherapies.

Evaluation of the Immune Response within the Tumor Microenvironment in African American and Non-Hispanic White Patients with Non-Small Cell Lung Cancer.

African Americans have higher incidence and mortality from lung cancer than non-Hispanic Whites, but investigations into differences in immune response have been minimal. Therefore, we compared components of the tumor microenvironment among African Americans and non-Hispanic Whites diagnosed with non-small cell lung cancer based on PDL1 or tertiary lymphoid structure (TLS) status to identify differences of translational relevance. Using a cohort of 280 patients with non-small cell lung cancer from the Inflammation, Health, Ancestry, and Lung Epidemiology study (non-Hispanic White: n = 155; African American: n = 125), we evaluated PDL1 tumor proportion score (<1% vs. ≥1%) and TLS status (presence/absence), comparing differences within the tumor microenvironment based on immune cell distribution and differential expression of genes. Tumors from African Americans had a higher proportion of plasma cell signatures within the tumor microenvironment than non-Hispanic Whites. In addition, gene expression patterns in African American PDL1-positive samples suggest that these tumors contained greater numbers of γδ T cells and resting dendritic cells, along with fewer CD8+ T cells after adjusting for age, sex, pack-years, stage, and histology. Investigation of differential expression of B cell/plasma cell-related genes between the two patient populations revealed that two immunoglobulin genes (IGKV2-29 and IGLL5) were associated with decreased mortality risk in African Americans. In the first known race-stratified analysis of tumor microenvironment components in lung cancer based on PDL1 expression or TLS status, differences within the immune cell composition and transcriptomic signature were identified that may have therapeutic implications. Future investigation of racial variation within the tumor microenvironment may help direct the use of immunotherapy.

Circulating T cell status and molecular imaging may predict clinical benefit of neoadjuvant PD-1 blockade in oral cancer

BackgroundAddition of neoadjuvant immune checkpoint inhibition to standard-of-care interventions for locally advanced oral cancer could improve clinical outcome.MethodsIn this study, 16 evaluable patients with stage III/IV oral cancer were treated...

Stimulator of Interferon Genes Protein (STING) Expression in Cancer Cells: A Tissue Microarray Study Evaluating More than 18,000 Tumors from 139 Different Tumor Entities.

Stimulator of interferon genes protein (STING) activates the immune response in inflammatory cells. STING expression in cancer cells is less well characterized, but STING agonists are currently being evaluated as anticancer drugs. A tissue microarray containing 18,001 samples from 139 different tumor types was analyzed for STING by immunohistochemistry. STING-positive tumor cells were found in 130 (93.5%) of 139 tumor entities. The highest STING positivity rates occurred in squamous cell carcinomas (up to 96%); malignant mesothelioma (88.5%-95.7%); adenocarcinoma of the pancreas (94.9%), lung (90.3%), cervix (90.0%), colorectum (75.2%), and gallbladder (68.8%); and serous high-grade ovarian cancer (86.0%). High STING expression was linked to adverse phenotypes in breast cancer, clear cell renal cell carcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, and papillary carcinoma of the thyroid (p < 0.05). In pTa urothelial carcinomas, STING expression was associated with low-grade carcinoma (p = 0.0002). Across all tumors, STING expression paralleled PD-L1 positivity of tumor and inflammatory cells (p < 0.0001 each) but was unrelated to the density of CD8+ lymphocytes. STING expression is variable across tumor types and may be related to aggressive tumor phenotype and PD-L1 positivity. The lack of relationship with tumor-infiltrating CD8+ lymphocytes argues against a significant IFN production by STING positive tumor cells.

Real‑world evidence of advanced non‑small cell lung carcinoma treated with an immune checkpoint inhibitor plus chemotherapy.

Immunotherapy is an effective treatment strategy for patients with advanced non-small cell lung cancer (NSCLC). Although clinical trials on immunotherapy have provided promising results, real-world research in clinical practice is needed to assess the effectiveness and safety of immunotherapy. The present study aimed to characterize real-world outcomes in patients with advanced NSCLC treated with immune checkpoint inhibitor (ICI)-based regimens. The medical records of patients with advanced NSCLC, who were treated with programmed cell death protein-1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) inhibitors, were reviewed for data collection. The primary objectives were to evaluate progression-free survival (PFS) and overall survival (OS). Therefore, multiple Cox regression models were used to investigate the predictive factors for survival outcomes. Furthermore, survival curves for PFS and OS were created using Kaplan-Meier estimates and compared using the log-rank test. The present study included a total of 133 patients with advanced NSCLC who received therapy with ICIs between January 1, 2019 and December 31, 2022. The final follow-up date was August 24, 2023. The median PFS and OS times were 9.8 and 27.2 months, respectively. Univariate Cox regression analysis demonstrated that sex, clinical stage, PD-L1 status, previous systemic therapy, and brain and liver metastases were associated with PFS, while Eastern Cooperative Oncology Group (ECOG) status, clinical stage, PD-L1 status and brain metastasis were associated with OS. Furthermore, multivariate Cox regression analysis demonstrated that a PD-L1 tumor proportion score (TPS) of ≥50% was an indicator of favorable PFS and OS. An ECOG performance status score of ≥1 was also associated with poor OS but not with PFS. Furthermore, brain metastasis was an indicator for poor PFS and OS, while liver metastasis was only associated with a poor PFS. Finally, the results of the present study demonstrated that PD-L1 status was an independent predictor for PFS and OS in patients with advanced NSCLC, especially adenocarcinoma, who were treated with ICIs plus chemotherapy. The results also suggested that patients with a PD-L1 TPS of ≥50% could benefit when the aforementioned regimens were administrated as a first-line or later-line therapy.

Characterization of Immune Infiltrate Along the Leading Edge of Differentiated Thyroid Cancer.

Background: Although the impact of tumor-immune infiltrate has been reported on differentiated thyroid cancer (DTC) behavior, the expression of immune checkpoints [programmed cell death protein 1 (PD-1) and its ligand (PD-L1)] alone has not been able to predict response to immunotherapies. We aimed to identify tumor-infiltrating immune cells and checkpoints associated with DTC. Methods: We performed multiplex immunofluorescence on deparaffinized thyroid tissue collected at thyroidectomy from 17 adults with DTC to characterize the tumor immune microenvironment for leukocytes (CD45+), T cells (CD3+), T regulatory cells (Tregs) (CD3+FOXP3+), CD4+ T cells (CD3+CD4+), CD8+ T cells (CD3+CD8+), macrophages (CD68+), M2 macrophages (CD68+CD163+), M1 Macrophages (CD68+ inducible nitric oxide synthase [iNOS]+), and immune checkpoints PD-1 and PD-L1. We compared the mean percentage expression of immune markers between tumor and adjacent thyroid tissue from the same patient by paired t-test and performed spatial analysis along the tumor's leading edge. Results: Immune checkpoints PD-1 and PD-L1 showed a significant increase in expression intratumorally as compared to adjacent thyroid tissue (p < 0.05). A higher trend for M2 macrophages was observed intratumorally compared to adjacent tissue. Along the leading edge, PD-L1 expression correlated negatively with CD45 and positively with CD163 intratumorally. On exploratory analysis, there was a nonsignificant trend for higher FOXP3 but less CD8 and iNOS expression in tumor from DTC with (n = 3) versus without distant metastases (n = 14). There was a nonsignificant trend for higher CD58 and iNOS expression in DTC with (n = 7) than without thyroiditis (n = 10). Conclusions: Higher tumoral PD-1 and PD-L1 expression indicate their role in DTC occurrence. A trend for more Tregs and M2 macrophages but less M1 macrophages intratumorally in patients with distant metastatic DTC, suggests their potential role as prognostic biomarkers. Future studies with larger sample sizes are needed to compare various clinicopathologic severities to harness tumor microenvironment for cancer prognostication and therapy.

Neoadjuvant PD-(L)1 blockade plus platinum-based chemotherapy for potentially resectable oncogene-positive non-small cell lung cancer

BackgroundWhether programmed cell death-1/ligand-1 (PD-1/PD-L1) blockade-based neoadjuvant treatment may benefit locally advanced oncogene-mutant non–small cell lung cancer (NSCLC) patients remains controversial. This retrospective study was designed to observe the efficacy and safety of neoadjuvant PD-1/PD-L1 blockade plus chemotherapy versus chemotherapy and corresponding tyrosine kinase inhibitors (TKIs) in patients with resectable oncogene-positive NSCLC.MethodsPatients with potential resectable NSCLC harbouring oncogene alterations who had received neoadjuvant treatment were retrospectively recruited, and an oncogene-negative cohort of patients who received neoadjuvant PD-(L)1 blockade-based neoadjuvant treatment was reviewed for comparison during the same period. The primary aim was to observe the treatment efficacy and event-free survival (EFS) of these agents. Safety profile, molecular target, and immunologic factor data, including PD-L1 expression and tumour mutational burden (TMB), were also obtained.ResultsA total of 46 patients were recruited. Thirty-one of them harboured oncogene alterations, including EGFR, KRAS, ERBB2, ROS1, MET, RET, ALK, and FGFR3 alterations. Among the oncogene-positive patients, 18 patients received neoadjuvant PD-(L)1 blockade immunotherapy plus chemotherapy (oncogene-positive IO group), 13 patients were treated with neoadjuvant chemotherapy and/or corresponding TKIs or TKIs alone (oncogene-positive chemo/TKIs group), and the other 15 patients were oncogene negative and received neoadjuvant PD-(L)1 blockade plus chemotherapy (oncogene-negative IO group). The pathological complete response (pCR) and major pathological response (MPR) rates were 22.2% (4 of 18) and 44.4% (8 of 18) in the oncogene-positive IO group, 0% (P = 0.120) and 23.1% (3 of 13) (P = 0.276) in the oncogene-positive chemo/TKIs group, and 46.7% (7 of 15) (P = 0.163) and 80.0% (12 of 15) (P = 0.072) in the oncogene-negative IO group, respectively. By the last follow-up, the median EFS time had not reached in the oncogene-positive IO group, and was 29.5 months in the oncogene-positive chemo/TKIs group and 38.4 months in the oncogene-negative IO group.ConclusionCompared with chemotherapy/TKIs treatment, neoadjuvant treatment with PD-(L)1 blockade plus platinum-based chemotherapy was associated with higher pCR/MPR rates in patients with partially resectable oncogene-mutant NSCLC, while the pCR/MPR rates were lower than their oncogene-negative counterparts treated with PD-(L)1 blockade-based treatment. Specifically, oncogene alteration types and other predictors of response to immunotherapy should be taken into account in clinical practice.

Differential predictive value of tissue-specific PD-L1 expression scores in adjuvant immunotherapy of melanoma.

Adjuvant treatment of stage II-IV melanoma with PD-1-based immune checkpoint inhibitors (ICI) has improved relapse-free survival (RFS) and has therefore become a standard-of-care treatment option. Approximately 25%-30% of patients still recur within 1 year. Predictive biomarkers reflecting real-world data are desired. The predictive relevance of tumour tissue PD-L1 expression in the adjuvant setting remains inconclusive. This retrospective, observational study was conducted to evaluate the value of PD-L1 expression scores in different tumour tissue locations in predicting response towards adjuvant immunotherapeutic treatment. Tumour tissue taken prior to anti-PD-1 adjuvant ICI in 243 stage II-IV melanoma patients was collected at University Skin Cancer Center Hamburg. PD-L1 expression was evaluated on immune cells (ICS), tumour cells (TPS) and combined (CPS). Scores were determined by independent pathological physician quantification and correlated with therapy outcome at different cut-off (CO) levels (relapse-free survival, RFS) for different tumour tissue locations (primary tumour, metastases). A total of 104 patients were eligible for analysis. Positivity of ICS, TPS and CPS showed no predictive RFS outcome association at different CO levels when analysed irrespective of tissue origin. In primary tumours, ICS at CO 1% showed a significantly improved RFS upon positivity (HR 0.22). In contrast, positivity to TPS (CO 1%) correlated significantly and independently with improved RFS when evaluated in metastatic tumour tissue specimens (HR 0.37). PD-L1 tumour tissue expression may serve as a predictive biomarker for adjuvant ICI treatment response stratification in melanoma, but caution should be spent on the origin of tumour tissue analysed. The cell-type relevant for the predictive value of PD-L1 expression is tissue-specific with immune cells being important in primary tumours while tumour cells are key in metastases. The present results should be validated in a multicentre cohort.

KRAS and TP53 co-mutation predicts benefit of immune checkpoint blockade in lung adenocarcinoma

BackgroundPredictive biomarkers in use for immunotherapy in advanced non-small cell lung cancer are of limited sensitivity and specificity. We analysed the potential of activating KRAS and pathogenic TP53 mutations to provide additional predictive information.MethodsThe study cohort included 713 consecutive immunotherapy patients with advanced lung adenocarcinomas, negative for actionable genetic alterations. Additionally, two previously published immunotherapy and two surgical patient cohorts were analyzed. Therapy benefit was stratified by KRAS and TP53 mutations. Molecular characteristics underlying KRASmut/TP53mut tumours were revealed by the analysis of TCGA data.ResultsAn interaction between KRAS and TP53 mutations was observed in univariate and multivariate analyses of overall survival (Hazard ratio [HR] = 0.56, p = 0.0044 and HR = 0.53, p = 0.0021) resulting in a stronger benefit for KRASmut/TP53mut tumours (HR = 0.71, CI 0.55–0.92). This observation was confirmed in immunotherapy cohorts but not observed in surgical cohorts. Tumour mutational burden, proliferation, and PD-L1 mRNA were significantly higher in TP53-mutated tumours, regardless of KRAS status. Genome-wide expression analysis revealed 64 genes, including CX3CL1 (fractalkine), as specific transcriptomic characteristic of KRASmut/TP53mut tumours.ConclusionsKRAS/TP53 co-mutation predicts ICI benefit in univariate and multivariate survival analyses and is associated with unique molecular tumour features. Mutation testing of the two genes can be easily implemented using small NGS panels.

Evaluating tumor inflammation and PD-L1 expression in sequential biopsies of real-world primary and metastatic breast cancer.

e13035 Background: Biomarkers for measuring immunogenicity of tumors such as PD-L1 immunohistochemistry (IHC), tumor mutational burden (TMB), and immune gene expression have been studied in many cancers including breast cancer. How these biomarkers change over time and how their detection differs with sequential testing in the real-world clinical setting has been studied to a lesser extent but is an important consideration for optimal patient care. Methods: We performed an analysis of 30 patients with primary and metastatic breast cancer sequentially tested by comprehensive genomic and immune profiling (CGIP) at two time points during routine clinical care to observe temporal changes in immunotherapy markers and immune gene expression. Genomic variants and TMB were assessed with DNA-seq, while immune gene expression was assessed with RNA-seq. PD-L1 expression was determined using IHC. Immune gene expression signatures characterizing the tumor microenvironment (TME) were calculated, including tumor inflammation (TIGS), cell proliferation (CP), and cancer testis antigen burden (CTAB). Differences between sequential tests were tested for using linear mixed effect models. Results: Time between biopsies for sequential tests ranged from the same day to 4.5 years, with 40% of specimens being collected within 30 days of the first. Sequential specimens were collected from breast (27%), non-breast (40%), or a mix of breast and non-breast (33%) tissue. Non-breast tissue types included sites from lymph node (18%), GI tract (15%), skin (10%), thorax (7%), and musculoskeletal sites (7%). Overall, TMB, PD-L1 IHC, and gene expression signatures were relatively stable between sequential tests (P &gt; 0.05); however, trends were noted for second tests detecting lower tumor inflammation (TIGS score) and PD-L1 IHC (P = 0.1). Further, second tests detected significantly lower levels of tumor inflammation when both were performed on non-breast tissue (P = 0.04), but not when performed on all breast (P = 0.7) or a mix of breast and non-breast (P = 0.6) tissues. An opposite trend was noted for PD-L1 where second tests detected lower levels of PD-L1 IHC when both tests were performed on breast tissue (P = 0.1), but not when performed on all non-breast (P = 0.4) or a mix of breast and non-breast (P = 0.5) tissue. Tissue-dependent trends were still present even when excluding lymph node specimens (P = 0.1). Conclusions: Changes in immunotherapy markers and immune gene expression signatures, on average, remained relatively stable over time, except for tumor inflammation and PD-L1 IHC when sequentially testing all non-breast or breast tissue, respectively. These observations highlight the utility of clinical CGIP testing in revealing temporal changes of the TME, which may help inform clinical trial or treatment strategies occurring over time for primary and metastatic breast cancer.

Five-year outcomes with first-line (1L) nivolumab + ipilimumab + chemotherapy (N + I + C) vs C in patients (pts) with metastatic NSCLC (mNSCLC) in CheckMate 9LA.

8560 Background: InCheckMate 9LA (NCT03215706), 1L N + I + C demonstrated long-term, durable survival benefit vs C alone in pts with mNSCLC, regardless of tumor PD-L1 expression or histology. Here, we report updated efficacy and safety data with a 5-y follow up (f/u) and outcomes in 5-y survivors. Methods: Adults with stage IV or recurrent NSCLC, ECOG PS ≤ 1, and EGFR/ALK wild-type were randomized 1:1 to N 360 mg Q3W + I 1 mg/kg Q6W + C Q3W (2 cycles; n = 361) or C alone Q3W (4 cycles; n = 358). Maintenance pemetrexed was allowed for pts with non-squamous (NSQ) NSCLC (C arm only). Assessments were OS, PFS, ORR, DOR, treatment (tx)-free interval (TFI; time from last study tx dose to start of subsequent systemic tx or death), and safety. Exploratory analyses included quantifying the number of ipilimumab doses received by 5-y survivors, as well as PFS and TFI in these pts. Results: With a median f/u of 64.5 mo (database lock, 15 Dec 2023), clinical benefit continued to be seen with N + I + C vs C in all randomized pts (Table); 5-y OS rates were 18% vs 11%, respectively. Of pts treated with N + I + C, 11% were tx-free at 5 y. Clinical outcomes favored N + I + C vs C across tumor PD-L1 expression and histology subgroups (Table). In pts with tumor PD-L1 &lt; 1%, 5-y OS and PFS rates with N + I + C were both ~3-fold higher than with C, and 5-y DOR rates were 25% vs 0% in the respective tx arms. Among pts who discontinued N + I + C due to tx-related adverse events (TRAEs; n = 61), 37% were alive at 5 y, and the TFI rate was 22%. In analyses of 5-y survivors, PFS favored N + I + C (n = 48) vs C (n = 30; HR, 0.52 [95% CI, 0.26–1.02]), and 5-y TFI rates were 72% vs 35%, respectively. Of 5-y survivors in the N + I + C arm, 21/48 (44%) received ≥ 17 doses of ipilimumab; of those who received &lt; 17 doses, most had discontinued ipilimumab due to TRAEs. The extended f/u revealed no new safety signals. Conclusions: 1L N + I + C maintained long-term, durable survival benefit vs C in pts with mNSCLC at this 5-y f/u, particularly in pts with tumor PD-L1 expression &lt; 1% or squamous (SQ) histology. N + I + C increased 5-y survivorship, with improved PFS and TFI in 5-y survivors over C. These data further underscore 1L N + I + C as an efficacious tx option for pts with mNSCLC. Clinical trial information: NCT03215706 . [Table: see text]

Intrapatient variation in PD-L1 expression and tumor mutational burden and the impact on outcomes to immune checkpoint inhibitor therapy in patients with non-small-cell lung cancer

Programmed death receptor ligand 1 (PD-L1) tumor proportion score (TPS) and tumor mutational burden (TMB) are key predictive biomarkers for immune checkpoint inhibitor (ICI) efficacy in non-small-cell lung cancer (NSCLC). Data on their variation across multiple samples are limited. Patients with NSCLC and multiple PD-L1 TPS and/or TMB assessments were included. Clinicopathologic and genomic data were analyzed according to PD-L1 and TMB variation. In total, 402 PD-L1 sample pairs and 413 TMB sample pairs were included. Concordance between pairs was moderate for PD-L1 (ρ= 0.53, P < 0.0001) and high for TMB (ρ= 0.80, P < 0.0001). Shorter time between biopsies correlated with higher concordance in PD-L1, but not in TMB. Major increases (ΔTPS ≥+50%) and decreases (ΔTPS ≤-50%) in PD-L1 were observed in 9.7% and 8.0% of cases, respectively. PD-L1, but not TMB, decreased with intervening ICI (P= 0.02). Acquired copy number loss of CD274, PDCD1LG2, and JAK2 were associated with major decrease in PD-L1 (q < 0.05). Among patients with multiple PD-L1 assessments before ICI, cases where all samples had a PD-L1 ≥1%, compared to cases with at least one sample with PD-L1 <1% and another with PD-L1 ≥1%, achieved improved objective response rate and progression-free survival (PFS). Among patients with at least one PD-L1 <1% and one ≥1% before ICI, cases where the most proximal sample was PD-L1 ≥1% had longer median PFS compared to cases where the most proximal PD-L1 was <1%. Among patients with multiple TMB assessments before ICI, patients with a TMB ≥10 mut/Mb based on the most recent assessment, as compared to those with a TMB <10 mut/Mb, achieved improved PFS and overall survival to ICI; instead, no differences were observed when patients were categorized using the oldest TMB assessment. Despite intrapatient concordance in PD-L1 and TMB, variation in these biomarkers can influence ICI outcomes, warranting consideration for reassessment before ICI initiation when feasible.

Multiplex analysis of the immune environment before and after neoadjuvant durvalumab as a prognostic factor in resectable non-small cell lung cancer (NSCLC) in the IFCT-1601 IONESCO phase 2 trial.

8022 Background: Immune checkpoint inhibitors (ICI) are currently included in the peri-operative standard of care for NSCLC with the objective of a curative strategy. In early stages of NSCLC, biomarkers predicting ICI efficacy should be more stringent than PD-L1 tumoral expression in order to improve the benefit-toxicity ratio. We deeply analyzed the tumor microenvironment of patients included in the IONESCO multicenter phase 2 trial (stage IB &gt; 4cm–IIIA, non N2 resectable NSCLC). Diagnostic biopsies and surgical resection specimen after 3 cycles of Durvalumab were available. We previously showed that the % of residual viable tumor cells (RVT) was associated with disease free survival (DFS) and overall survival (OS). PD-L1 tumor positive score was not correlated to RVT nor survival. Methods: 46 patients were included in the IONESCO trial. Among them, diagnostic biopsy (n = 32), surgical resection specimen post durvalumab (n = 39) and paired tumor samples (n = 31) were analyzed. Immune environment was assessed using 7 quantitative 7-plex immunofluorescence panels generating 349 different cellular phenotypes in 3 different compartments (whole tumor, intra cytokeratin and stroma), focusing on T and B lymphocytes, macrophages, immune checkpoint, NK cells, apoptosis, innate and adaptive immunity, dendritic cells. Densities of cells were quantified using Fluorescent Multiplex immunohistochemistry performed on Leica Bond RX, using OpalTM technology. A fisher's exact test or chi2 test was used for demographics variables and RVT. HRs and 95% CIs were estimated using a Cox model. NCT number: NCT03030131. Results: With median follow-up of 4.5 years, 16/31 patients had a disease recurrence. Histology, sex, stage and survival were significantly associated with intra-tumor densities of CD3, CD8, PD1, TIM3, and CD163 cells in the diagnostic biopsy, and with the delta of CD3, FoxP3, CD4, CD163PD1, TIM3, PDL1 on immune cells and TIM3PDL1 cells, between biopsy and surgical specimen. DFS was significantly associated with high density of CD8+TIM3+ in biopsies (HR = 0.25 [0.09-0.71], p = 0.0092) and with the high density of CD20+ cells in surgical specimen (HR = 0.36 [0.13-0.97], p = 0.04). The RVT was significantly associated with CK+Caspase3- cells and CK+PDL1+ cells in the surgical specimen. No biomarker was associated with OS. Conclusions: Multiparameter analysis of the immune NSCLC environment of patients treated with neoadjuvant anti-PDL1 allows identification of markers associated with clinical, pathological parameters and DFS. Our findings highlight the substantial impact of high CD8+TIM3+ cell density pre-durvalumab and of high CD20+ cell density post-durvalumab on DFS. These findings deserve to be assessed in patients treated with neoadjuvant combined immunotherapy chemotherapy. Clinical trial information: NCT03030131 .

QUIC: Phase 2 study of gemcitabine, cisplatin, quemliclustat (AB680), and zimberelimab (AB122) during first-line treatment of advanced biliary tract cancers (BTC)—Big Ten Cancer Research Consortium study BTCRC-GI22-564.

TPS4195 Background: Despite recent approvals of immune checkpoint inhibitors with chemotherapy in the first-line setting, the median overall survival (mOS) for patients with advanced biliary tract cancer (BTC) remains less than 15 months. CD73 is a key enzyme responsible for the conversion of extracellular adenosine 5’-monophosphate into adenosine and may play an important role in creating an immunosuppressed tumor microenvironment. High expression of CD73 in BTC is associated with decreased OS. Quemliclustat (Q) is a potent, selective, reversible inhibitor of CD73. Q in combination with chemotherapy has demonstrated promising activity in patients with advanced pancreatic cancer without significant increase in adverse events. The BTCRC-GI22-564 study evaluates safety and preliminary efficacy of Q in combination with zimberelimab (Z), a monoclonal antibody targeting human PD-1, with gemcitabine and cisplatin (GC) as first-line therapy for patients with advanced BTC, QUIC (Q and Immunotherapy in Cholangiocarcinoma). Methods: This is an open label, single arm, phase II multi-site trial, evaluating Q and Z in combination with GC in patients with advanced BTC who have not received systemic treatment for advanced disease or who completed adjuvant therapy &gt; 6 months prior to development of recurrent disease. Chemotherapy is given on days 1, 8, 22 and 29 of each 42-day cycle as per local standards. Z is administered at a fixed dose of 360 mg via IV infusion every 3 weeks. Q is administered via IV infusion on days 1, 15, and 29. A safety run-in portion built into the study is planned to enroll 6 subjects to ensure there are no dose limiting toxicities (DLT). If a study defined DLT is observed, Q, gemcitabine and cisplatin will be reduced by 1 dose level, and an additional 6 subjects will be enrolled in the safety run-in portion. The primary efficacy endpoint is median progression free survival (mPFS) with null and alternative survival of 6.0 and 10.0 months, respectively. Based on an accrual rate of 3 patients per month, we expect to accrue 33-39 patients which will provide at least 83% power with a one-sided alpha of 0.1. Secondary endpoints include mOS, disease control rate, overall response rate, and duration of response. Correlative endpoints will assess clinical outcomes with immune infiltration within tumor microenvironment, CD73 and PD-L1 expression. The QUIC study is currently open to enrollment through BTCRC. Clinical trial information: NCT06048133 .

Safety and immunological effects of ablative radiotherapy followed by pembrolizumab in patients with advanced adrenocortical carcinoma.

TPS4630 Background: Adrenocortical carcinoma (ACC) is a rare and aggressive cancer with poor prognosis. While pembrolizumab is a NCCN recommended treatment, our prior study showed no benefit in patients with liver metastases (NCT02673333).1 Preclinical evidence suggests combining liver-directed radiation therapy (RT) with pembrolizumab might enhance anti-tumor immunity.2 Our current study will assess the safety and describe preliminary efficacy data for ablative RT to symptomatic liver metastases followed by treatment with pembrolizumab in patients with advanced ACC. Methods: This is a single-center pilot study. Main inclusion criteria include: adult patients with metastatic ACC with symptomatic liver metastases, presence of extrahepatic metastases, ECOG 0-1. Ablative RT in 5 or 10 once daily fractions will be delivered over 1 to 2 weeks; pembrolizumab treatment (200mg Q3W) will begin one week after RT completion. The primary objective is to evaluate the safety of treatment with ablative RT followed by pembrolizumab. The study will include a 6 patient safety lead-in, with 10 to 12 patients enrolled in total. The secondary endpoint, efficacy, is defined as the objective response (partial and complete response) according to RECIST v1.1, in the hepatic and extrahepatic disease. Correlative objectives include evaluation of the innate and adaptive immune response during treatment through analysis of pre- and on-treatment blood and tumor tissue samples, circulating tumor (ct) DNA analyses, and PD-L1 and next-generation sequencing testing in pre-treatment tumor tissue samples to evaluate for biomarkers of response and resistance. This trial began enrollment in 9/27/2023, with 3 patients enrolled to date.