An integrated single-cell RNA-seq map of human neuroblastoma tumors and preclinical models uncovers divergent mesenchymal-like gene expression programs.

Neuroblastoma is a common pediatric cancer, where preclinical studies suggest that a mesenchymal-like gene expression program contributes to chemotherapy resistance. However, clinical outcomes remain poor, implying we need a better understanding of the relationship between patient tumor heterogeneity and preclinical models. Here, we generated single-cell RNA-seq maps of neuroblastoma cell lines, patient-derived xenograft models (PDX), and a genetically engineered mouse model (GEMM). We developed an unsupervised machine learning approach ('automatic consensus nonnegative matrix factorization' (acNMF)) to compare the gene expression programs found in preclinical models to a large cohort of patient tumors. We confirmed a weakly expressed, mesenchymal-like program in otherwise adrenergic cancer cells in some pre-treated high-risk patient tumors, but this appears distinct from the presumptive drug-resistance mesenchymal programs evident in cell lines. Surprisingly however, this weak-mesenchymal-like program was maintained in PDX and could be chemotherapy-induced in our GEMM after only 24 hours, suggesting an uncharacterized therapy-escape mechanism. Collectively, our findings improve the understanding of how neuroblastoma patient tumor heterogeneity is reflected in preclinical models, provides a comprehensive integrated resource, and a generalizable set of computational methodologies for the joint analysis of clinical and pre-clinical single-cell RNA-seq datasets.

Conditional c-MYC activation in catecholaminergic cells drives distinct neuroendocrine tumors: neuroblastoma vs somatostatinoma.

The MYC proto-oncogenes (c-MYC, MYCN , MYCL ) are among the most deregulated oncogenic drivers in human malignancies including high-risk neuroblastoma, 50% of which are MYCN -amplified. Genetically engineered mouse models (GEMMs) based on the MYCN transgene have greatly expanded the understanding of neuroblastoma biology and are powerful tools for testing new therapies. However, a lack of c-MYC-driven GEMMs has hampered the ability to better understand mechanisms of neuroblastoma oncogenesis and therapy development given that c-MYC is also an important driver of many high-risk neuroblastomas. In this study, we report two transgenic murine neuroendocrine models driven by conditional c-MYC induction in tyrosine hydroxylase (Th) and dopamine ß-hydroxylase (Dbh)-expressing cells. c-MYC induction in Th-expressing cells leads to a preponderance of Pdx1 + somatostatinomas, a type of pancreatic neuroendocrine tumor (PNET), resembling human somatostatinoma with highly expressed gene signatures of δ cells and potassium channels. In contrast, c-MYC induction in Dbh-expressing cells leads to onset of neuroblastomas, showing a better transforming capacity than MYCN in a comparable C57BL/6 genetic background. The c-MYC murine neuroblastoma tumors recapitulate the pathologic and genetic features of human neuroblastoma, express GD2, and respond to anti-GD2 immunotherapy. This model also responds to DFMO, an FDA-approved inhibitor targeting ODC1, which is a known MYC transcriptional target. Thus, establishing c-MYC-overexpressing GEMMs resulted in different but related tumor types depending on the targeted cell and provide useful tools for testing immunotherapies and targeted therapies for these diseases.

RBM39 degrader invigorates natural killer cells to eradicate neuroblastoma despite cancer cell plasticity.

The cellular plasticity of neuroblastoma is defined by a mixture of two major cell states, adrenergic (ADRN) and mesenchymal (MES), which may contribute to therapy resistance. However, how neuroblastoma cells switch cellular states during therapy remains largely unknown and how to eradicate neuroblastoma regardless of their cell states is a clinical challenge. To better understand the lineage switch of neuroblastoma in chemoresistance, we comprehensively defined the transcriptomic and epigenetic map of ADRN and MES types of neuroblastomas using human and murine models treated with indisulam, a selective RBM39 degrader. We showed that cancer cells not only undergo a bidirectional switch between ADRN and MES states, but also acquire additional cellular states, reminiscent of the developmental pliancy of neural crest cells. The lineage alterations are coupled with epigenetic reprogramming and dependency switch of lineage-specific transcription factors, epigenetic modifiers and targetable kinases. Through targeting RNA splicing, indisulam induces an inflammatory tumor microenvironment and enhances anticancer activity of natural killer cells. The combination of indisulam with anti-GD2 immunotherapy results in a durable, complete response in high-risk transgenic neuroblastoma models, providing an innovative, rational therapeutic approach to eradicate tumor cells regardless of their potential to switch cell states.

Results of a Randomized, Double-Blind, Placebo-Controlled, Phase 1b/2 Trial of Nabpaclitaxel + Gemcitabine ± Olaratumab in Treatment-Naïve Participants with Metastatic Pancreatic Cancer.

The efficacy and safety of olaratumab plus nabpaclitaxel and gemcitabine in treatment-naïve participants with metastatic pancreatic ductal adenocarcinoma was evaluated. An initial phase 1b dose-escalation trial was conducted to determine the olaratumab dose for the phase 2 trial, a randomized, double-blind, placebo-controlled trial to compare overall survival (OS) in the olaratumab arm vs. placebo arms. In phase 1b, 22 participants received olaratumab at doses of 15 and 20 mg/kg with a fixed dose of nabpaclitaxel and gemcitabine. In phase 2, 159 participants were randomized to receive olaratumab 20 mg/kg in cycle 1 followed by 15 mg/kg in the subsequent cycles (n = 81) or the placebo (n = 78) on days 1, 8, and 15 of a 28-day cycle, plus nabpaclitaxel and gemcitabine. The primary objective of the trial was not met, with a median OS of 9.1 vs. 10.8 months (hazard ratio [HR] = 1.05; 95% confidence interval [CI]: 0.728, 1.527; p = 0.79) and the median progression-free survival (PFS) was 5.5 vs. 6.4 months (HR = 1.19; 95% CI: 0.806, 1.764; p = 0.38), in the olaratumab vs. placebo arms, respectively. The most common treatment-emergent adverse event of any grade across both arms was fatigue. Olaratumab plus chemotherapy failed to improve the OS or PFS in participants with metastatic PDAC. There were no new safety signals.

Ezabenlimab (BI 754091), an anti-PD-1 antibody, in patients with advanced solid tumours.

BACKGROUND: Ezabenlimab (BI 754091) is a humanised monoclonal antibody targeting programmed cell death protein-1. We report results from open-label, dose-escalation/expansion, Phase I trials that evaluated the safety, maximum tolerated dose (MTD), pharmacokinetics and antitumour activity of ezabenlimab at the recommended Phase II dose in patients with selected advanced solid tumours. STUDY DESIGN: Study 1381.1 (NCT02952248) was conducted in Canada, the United Kingdom and the United States. Study 1381.4 (NCT03433898) was conducted in Japan. Study 1381.3 (NCT03780725) was conducted in the Netherlands. The primary endpoints were: number of patients experiencing dose-limiting toxicities (DLTs) in the first cycle (dose escalation parts), number of patients with DLTs during the entire treatment period and objective response (dose expansion part of Study 1381.1). RESULTS: Overall, 117 patients received ezabenlimab intravenously every 3 weeks (80 mg, n = 3; 240 mg, n = 111; 400 mg, n = 3). No DLTs were observed and the MTD was not reached. Fifty-eight patients (52.3%) had grade ≥ 3 adverse events, most commonly anaemia (10.8%) and fatigue (2.7%). In 111 assessed patients treated with ezabenlimab 240 mg, disease control rate was 56.8% and objective response rate was 16.2%. Three patients had complete response; at data cut-off (November 2021) one remained in response and was still receiving ongoing treatment (duration of response [DoR]: 906 days). Partial responses occurred across several tumour types; DoR ranged from 67 to 757 days. CONCLUSIONS: Ezabenlimab was well tolerated and associated with durable antitumour activity in multiple solid tumours, comparable to other immune checkpoint inhibitors in similar patient populations and treatment settings.

A shared neoantigen vaccine combined with immune checkpoint blockade for advanced metastatic solid tumors: phase 1 trial interim results.

Therapeutic vaccines that elicit cytotoxic T cell responses targeting tumor-specific neoantigens hold promise for providing long-term clinical benefit to patients with cancer. Here we evaluated safety and tolerability of a therapeutic vaccine encoding 20 shared neoantigens derived from selected common oncogenic driver mutations as primary endpoints in an ongoing phase 1/2 study in patients with advanced/metastatic solid tumors. Secondary endpoints included immunogenicity, overall response rate, progression-free survival and overall survival. Eligible patients were selected if their tumors expressed one of the human leukocyte antigen-matched tumor mutations included in the vaccine, with the majority of patients (18/19) harboring a mutation in KRAS. The vaccine regimen, consisting of a chimp adenovirus (ChAd68) and self-amplifying mRNA (samRNA) in combination with the immune checkpoint inhibitors ipilimumab and nivolumab, was shown to be well tolerated, with observed treatment-related adverse events consistent with acute inflammation expected with viral vector-based vaccines and immune checkpoint blockade, the majority grade 1/2. Two patients experienced grade 3/4 serious treatment-related adverse events that were also dose-limiting toxicities. The overall response rate was 0%, and median progression-free survival and overall survival were 1.9 months and 7.9 months, respectively. T cell responses were biased toward human leukocyte antigen-matched TP53 neoantigens encoded in the vaccine relative to KRAS neoantigens expressed by the patients' tumors, indicating a previously unknown hierarchy of neoantigen immunodominance that may impact the therapeutic efficacy of multiepitope shared neoantigen vaccines. These data led to the development of an optimized vaccine exclusively targeting KRAS-derived neoantigens that is being evaluated in a subset of patients in phase 2 of the clinical study. ClinicalTrials.gov registration: NCT03953235 .

Biomarker-directed targeted therapy plus durvalumab in advanced non-small-cell lung cancer: a phase 2 umbrella trial.

For patients with non-small-cell lung cancer (NSCLC) tumors without currently targetable molecular alterations, standard-of-care treatment is immunotherapy with anti-PD-(L)1 checkpoint inhibitors, alone or with platinum-doublet therapy. However, not all patients derive durable benefit and resistance to immune checkpoint blockade is common. Understanding mechanisms of resistance-which can include defects in DNA damage response and repair pathways, alterations or functional mutations in STK11/LKB1, alterations in antigen-presentation pathways, and immunosuppressive cellular subsets within the tumor microenvironment-and developing effective therapies to overcome them, remains an unmet need. Here the phase 2 umbrella HUDSON study evaluated rational combination regimens for advanced NSCLC following failure of anti-PD-(L)1-containing immunotherapy and platinum-doublet therapy. A total of 268 patients received durvalumab (anti-PD-L1 monoclonal antibody)-ceralasertib (ATR kinase inhibitor), durvalumab-olaparib (PARP inhibitor), durvalumab-danvatirsen (STAT3 antisense oligonucleotide) or durvalumab-oleclumab (anti-CD73 monoclonal antibody). Greatest clinical benefit was observed with durvalumab-ceralasertib; objective response rate (primary outcome) was 13.9% (11/79) versus 2.6% (5/189) with other regimens, pooled, median progression-free survival (secondary outcome) was 5.8 (80% confidence interval 4.6-7.4) versus 2.7 (1.8-2.8) months, and median overall survival (secondary outcome) was 17.4 (14.1-20.3) versus 9.4 (7.5-10.6) months. Benefit with durvalumab-ceralasertib was consistent across known immunotherapy-refractory subgroups. In ATM-altered patients hypothesized to harbor vulnerability to ATR inhibition, objective response rate was 26.1% (6/23) and median progression-free survival/median overall survival were 8.4/22.8 months. Durvalumab-ceralasertib safety/tolerability profile was manageable. Biomarker analyses suggested that anti-PD-L1/ATR inhibition induced immune changes that reinvigorated antitumor immunity. Durvalumab-ceralasertib is under further investigation in immunotherapy-refractory NSCLC.ClinicalTrials.gov identifier: NCT03334617.

Anti-TIGIT antibody improves PD-L1 blockade through myeloid and Treg cells.

Tiragolumab, an anti-TIGIT antibody with an active IgG1κ Fc, demonstrated improved outcomes in the phase 2 CITYSCAPE trial (ClinicalTrials.gov: NCT03563716 ) when combined with atezolizumab (anti-PD-L1) versus atezolizumab alone1. However, there remains little consensus on the mechanism(s) of response with this combination2. Here we find that a high baseline of intratumoural macrophages and regulatory T cells is associated with better outcomes in patients treated with atezolizumab plus tiragolumab but not with atezolizumab alone. Serum sample analysis revealed that macrophage activation is associated with a clinical benefit in patients who received the combination treatment. In mouse tumour models, tiragolumab surrogate antibodies inflamed tumour-associated macrophages, monocytes and dendritic cells through Fcγ receptors (FcγR), in turn driving anti-tumour CD8+ T cells from an exhausted effector-like state to a more memory-like state. These results reveal a mechanism of action through which TIGIT checkpoint inhibitors can remodel immunosuppressive tumour microenvironments, and suggest that FcγR engagement is an important consideration in anti-TIGIT antibody development.

STAR-121: A Phase III Randomized Study of Domvanalimab and Zimberelimab in Combination With Chemotherapy Versus Pembrolizumab With Chemotherapy in Untreated Metastatic Non-Small Cell Lung Cancer With No Actionable Gene Alterations.

INTRODUCTION: Dual inhibition with a T-cell immunoreceptor with immunoglobulin and ITIM domains plus programmed death (ligand)-1 (PD[L]-1) inhibitors, with or without chemotherapy, is an emerging therapeutic strategy in metastatic non-small cell lung cancer (mNSCLC). The STAR-121 (NCT05502237) phase III, global, randomized, open-label study will investigate first-line domvanalimab (anti-TIGIT) and zimberelimab (anti-PD-1) plus chemotherapy versus pembrolizumab plus chemotherapy in mNSCLC with no actionable gene alterations. PARTICIPANTS AND METHODS: Approximately 720 participants (≥18 years old) with untreated mNSCLC and no EGFR and ALK mutations will be randomized into 3 groups (A, B, or C) in a 4:4:1 ratio and stratified by baseline PD-L1 expression (tumor cells <50% vs. ≥50%), histology (squamous vs. nonsquamous), and geographic region (East Asia vs. non-East Asia). Group A will receive domvanalimab 1200 mg plus zimberelimab 360 mg plus platinum-doublet chemotherapy (PT), group B will receive pembrolizumab 200 mg plus PT, and group C will receive zimberelimab 360 mg plus PT, every 3 weeks. Treatment will be administered until disease progression or intolerable toxicity. Dual primary endpoints are progression-free survival (by blinded independent central review [BICR]) and overall survival for group A versus B. Key secondary endpoints comprise overall response rate (by BICR), safety, and quality of life. Exploratory endpoints include efficacy and safety between groups A and C, pharmacokinetics, patient-reported outcomes, and biomarkers. CONCLUSION: Enrollment in the STAR-121 study commenced on October 12, 2022, and is currently ongoing with completion planned by September 2024. The study completion is expected by December 2027.

A plain language summary of the PHAROS study: the combination of encorafenib and binimetinib for people with BRAF V600E-mutant metastatic non-small cell lung cancer.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of the results of a study called PHAROS. This study looked at combination treatment with encorafenib (BRAFTOVI®) and binimetinib (MEKTOVI®). This combination of medicines was studied in people with metastatic non-small-cell lung cancer (NSCLC). NSCLC is the most common type of lung cancer. Metastatic means that the cancer has spread to other parts of the body. All people in this study had a type of NSCLC that has a change in a gene called BRAF termed a BRAF V600E mutation. A gene is a part of the DNA that has instructions for making things that your body needs to work, and the BRAF V600E mutation contributes to the growth of the lung cancer. WHAT WERE THE RESULTS?: In this study, 98 people with BRAF V600E-mutant metastatic NSCLC were treated with the combination of encorafenib and binimetinib (called encorafenib plus binimetinib in this summary). Before starting the study, 59 people had not received any treatment for their metastatic NSCLC, and 39 people had received previous anticancer treatment. At the time of this analysis, 44 (75%) out of 59 people who did not receive any treatment before taking encorafenib plus binimetinib had their tumors shrink or disappear. Eighteen (46%) out of 39 people who had received treatment before starting encorafenib plus binimetinib also had their tumors shrink or disappear. The most common side effects of encorafenib plus binimetinib were nausea, diarrhea, fatigue, and vomiting. WHAT DO THE RESULTS MEAN?: These results support the use of encorafenib plus binimetinib combination treatment as a new treatment option in people with BRAF V600E-mutant metastatic NSCLC. The side effects of encorafenib plus binimetinib in this study were similar to the side effects seen with encorafenib plus binimetinib in people with a type of skin cancer called metastatic melanoma.

Backbone cationized highly branched poly(ß-amino ester)s as enhanced delivery vectors in non-viral gene therapy.

Gene therapy holds great potential for treating Lung Cystic Fibrosis (CF) which is a fatal hereditary condition arising from mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in dysfunctional CFTR protein. However, the advancement and clinical application of CF gene therapy systems have been hindered due to the absence of a highly efficient delivery vector. In this work, we introduce a new generation of highly branched poly(ß-amino ester) (HPAE) gene delivery vectors for CF treatment. Building upon the classical chemical composition of HPAE, a novel backbone cationization strategy was developed to incorporate additional functional amine groups into HPAE without altering their branching degree. By carefully adjusting the type, proportion, and backbone distribution of the added cationic groups, a series of highly effective HPAE gene delivery vectors were successfully constructed for CF disease gene therapy. In vitro assessment results showed that the backbone cationized HPAEs with randomly distributed 10% proportion of 1-(3-aminopropyl)-4-methylpiperazine (E7) amine groups exhibited superior transfection performance than their counterparts. Furthermore, the top-performed backbone cationized HPAEs, when loaded with therapeutic plasmids, successfully reinstated CFTR protein expression in the CFBE41o- disease model, achieving levels 20-23 times higher than that of normal human bronchial epithelial (HBE) cells. Their therapeutic effectiveness significantly surpassed that of the currently advanced commercial vectors, Xfect and Lipofectamine 3000.

SKYSCRAPER-02: Tiragolumab in Combination With Atezolizumab Plus Chemotherapy in Untreated Extensive-Stage Small-Cell Lung Cancer.

PURPOSE: The phase III SKYSCRAPER-02 study determined whether the benefits of atezolizumab plus carboplatin and etoposide (CE) could be enhanced by the addition of tiragolumab in untreated extensive-stage small-cell lung cancer (ES-SCLC). We report final progression-free survival (PFS) and overall survival (OS) analyses. METHODS: Patients received tiragolumab 600 mg/placebo, plus atezolizumab 1,200 mg and CE (four cycles), then maintenance tiragolumab/placebo plus atezolizumab. Primary end points were investigator-assessed PFS and OS in patients without history/presence of brain metastases (primary analysis set [PAS]). Additional end points included PFS and OS in all patients regardless of brain metastases status (full analysis set [FAS]), response, and safety. RESULTS: Four hundred ninety patients were randomly assigned (FAS): 243 to tiragolumab arm and 247 to control arm. At the cutoff date (February 6, 2022; median duration of follow-up, 14.3 months [PAS] and 13.9 months [FAS]), final analysis of PFS in the PAS (n = 397) did not reach statistical significance (stratified hazard ratio [HR], 1.11; P = .3504; median, 5.4 months tiragolumab v 5.6 months control). At the cutoff date (September 6, 2022; median duration of follow-up, 21.2 months [FAS]), median OS in the PAS at final OS analysis was 13.1 months in both arms (stratified HR, 1.14; P = .2859). Median PFS and OS in the FAS were consistent with the PAS. The proportion of patients with immune-mediated adverse events (AEs) in the tiragolumab and control arms was 54.4% and 49.2%, respectively (grade 3/4: 7.9% and 7.7%). AEs leading to treatment withdrawal occurred in 8.4% and 9.3% of tiragolumab- and control-treated patients, respectively. CONCLUSION: Tiragolumab did not provide additional benefit over atezolizumab and CE in untreated ES-SCLC. The combination was well tolerated with no new safety signals.

Compromised Outcomes in Stage IV Non-Small-Cell Lung Cancer With Actionable Mutations Initially Treated Without Tyrosine Kinase Inhibitors: A Retrospective Analysis of Real-World Data.

PURPOSE: Identification and targeting of actionable oncogenic drivers (AODs) in advanced non-small-cell lung cancer (NSCLC) has dramatically improved outcomes. However, genomic testing uptake is variable and hampered by factors including slow turnaround time, frequently resulting in initial non-tyrosine kinase inhibitor (TKI) treatment. We investigate how this behavior affects outcomes. METHODS: This retrospective analysis of real-world, deidentified data from the Integra Connect Database included adults with stage IV NSCLC newly diagnosed from January 1, 2018, to December 31, 2020, with mutations of EGFR, ALK, ROS1, BRAF, MET, RET, ERBB2, or NTRK. Outcomes were reported as time to next treatment or death (TTNT) and overall survival (OS). RESULTS: Five hundred ten patients harboring AODs were identified and grouped as follows: group A (n = 379) were treated after the AOD was reported and served as the comparator. One hundred thirty-one patients treated before their AOD report were divided into group B (n = 47) who were initially started on chemotherapy and/or checkpoint inhibitor but switched to appropriate TKI within 35 days and group C (n = 84) who were also started empirically on non-TKI and did not switch within 35 days. Survival (OS) was significantly superior in group A compared with group C; TTNT was significantly superior in group A compared with groups B and C. CONCLUSION: For patients harboring AODs in advanced NSCLC, initial treatment before receipt of genomic test results yields significantly inferior outcomes and should be avoided. Molecular profiling panels with rapid turnaround times are essential to optimize patient outcomes and should be standard of care.

Patient-reported outcomes with durvalumab, with or without tremelimumab, plus chemotherapy as first-line treatment for metastatic non-small-cell lung cancer (POSEIDON).

OBJECTIVES: In the phase 3 POSEIDON study, first-line tremelimumab plus durvalumab and chemotherapy significantly improved overall survival and progression-free survival versus chemotherapy in metastatic non-small-cell lung cancer (NSCLC). We present patient-reported outcomes (PROs). PATIENTS AND METHODS: Treatment-naïve patients were randomized 1:1:1 to tremelimumab plus durvalumab and chemotherapy, durvalumab plus chemotherapy, or chemotherapy. PROs (prespecified secondary endpoints) were assessed using the European Organisation for Research and Treatment of Cancer 30-item core quality of life questionnaire version 3 (QLQ-C30) and its 13-item lung cancer module (QLQ-LC13). We analyzed time to deterioration (TTD) of symptoms, functioning, and global health status/quality of life (QoL) from randomization by log-rank test and improvement rates by logistic regression. RESULTS: 972/1013 (96 %) patients randomized completed baseline QLQ-C30 and QLQ-LC13 questionnaires, with scores comparable between treatment arms. Patients receiving tremelimumab plus durvalumab and chemotherapy versus chemotherapy had longer median TTD for all PRO items. Hazard ratios for TTD favored tremelimumab plus durvalumab and chemotherapy for all items except diarrhea; 95 % confidence intervals did not cross 1.0 for global health status/QoL, physical functioning, cognitive functioning, pain, nausea/vomiting, insomnia, constipation, hemoptysis, dyspnea, and pain in other parts. For durvalumab plus chemotherapy, median TTD was longer versus chemotherapy for all items except nausea/vomiting and diarrhea. Hazard ratios favored durvalumab plus chemotherapy for all items except appetite loss; 95 % confidence intervals did not cross 1.0 for global health status/QoL, physical functioning, role functioning, dyspnea, and pain in other parts. For both immunotherapy plus chemotherapy arms, improvement rates in all PRO items were numerically higher versus chemotherapy, with odds ratios > 1. CONCLUSIONS: Tremelimumab plus durvalumab and chemotherapy delayed deterioration in symptoms, functioning, and global health status/QoL compared with chemotherapy. Together with significant improvements in survival, these results support tremelimumab plus durvalumab and chemotherapy as a first-line treatment option in metastatic NSCLC.

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.).

Manipulating mitochondrial electron flow enhances tumor immunogenicity.

Although tumor growth requires the mitochondrial electron transport chain (ETC), the relative contribution of complex I (CI) and complex II (CII), the gatekeepers for initiating electron flow, remains unclear. In this work, we report that the loss of CII, but not that of CI, reduces melanoma tumor growth by increasing antigen presentation and T cell-mediated killing. This is driven by succinate-mediated transcriptional and epigenetic activation of major histocompatibility complex-antigen processing and presentation (MHC-APP) genes independent of interferon signaling. Furthermore, knockout of methylation-controlled J protein (MCJ), to promote electron entry preferentially through CI, provides proof of concept of ETC rewiring to achieve antitumor responses without side effects associated with an overall reduction in mitochondrial respiration in noncancer cells. Our results may hold therapeutic potential for tumors that have reduced MHC-APP expression, a common mechanism of cancer immunoevasion.

HERTHENA-Lung01, a Phase II Trial of Patritumab Deruxtecan (HER3-DXd) in Epidermal Growth Factor Receptor-Mutated Non-Small-Cell Lung Cancer After Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Therapy and Platinum-Based Chemotherapy.

PURPOSE: Patritumab deruxtecan, or HER3-DXd, is an antibody-drug conjugate consisting of a fully human monoclonal antibody to human epidermal growth factor receptor 3 (HER3) attached to a topoisomerase I inhibitor payload via a stable tetrapeptide-based cleavable linker. We assessed the efficacy and safety of HER3-DXd in patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC). METHODS: This phase II study (ClinicalTrials.gov identifier: NCT04619004) was designed to evaluate HER3-DXd in patients with advanced EGFR-mutated NSCLC previously treated with EGFR tyrosine kinase inhibitor (TKI) therapy and platinum-based chemotherapy (PBC). Patients received HER3-DXd 5.6 mg/kg intravenously once every 3 weeks or an uptitration regimen (3.2 → 4.8 → 6.4 mg/kg). The primary end point was confirmed objective response rate (ORR; RECIST 1.1) by blinded independent central review (BICR), with a null hypothesis of 26.4% on the basis of historical data. RESULTS: Enrollment into the uptitration arm closed early on the basis of a prespecified benefit-risk assessment of data from the phase I U31402-A-U102 trial. In total, 225 patients received HER3-DXd 5.6 mg/kg once every 3 weeks. As of May 18, 2023, median study duration was 18.9 (range, 14.9-27.5) months. Confirmed ORR by BICR was 29.8% (95% CI, 23.9 to 36.2); median duration of response, 6.4 months; median progression-free survival, 5.5 months; and median overall survival, 11.9 months. The subgroup of patients with previous osimertinib and PBC had similar outcomes. Efficacy was observed across a broad range of pretreatment tumor HER3 membrane expression levels and across diverse mechanisms of EGFR TKI resistance. In patients with nonirradiated brain metastases at baseline (n = 30), the confirmed CNS ORR by BICR per CNS RECIST was 33.3% (95% CI, 17.3 to 52.8). The safety profile (National Cancer Institute Common Terminology Criteria for Adverse Events v5.0) was manageable and tolerable, consistent with previous observations. CONCLUSION: After tumor progression with EGFR TKI therapy and PBC in patients with EGFR-mutated NSCLC, HER3-DXd once every 3 weeks demonstrated clinically meaningful efficacy with durable responses, including in CNS metastases. A phase III trial in EGFR-mutated NSCLC after progression on an EGFR TKI is ongoing (HERTHENA-Lung02; ClinicalTrials.gov identifier: NCT05338970).

MRTX1719 Is an MTA-Cooperative PRMT5 Inhibitor That Exhibits Synthetic Lethality in Preclinical Models and Patients with MTAP-Deleted Cancer.

Previous studies implicated protein arginine methyltransferase 5 (PRMT5) as a synthetic lethal target for MTAP-deleted (MTAP del) cancers; however, the pharmacologic characterization of small-molecule inhibitors that recapitulate the synthetic lethal phenotype has not been described. MRTX1719 selectively inhibited PRMT5 in the presence of MTA, which is elevated in MTAP del cancers, and inhibited PRMT5-dependent activity and cell viability with >70-fold selecti-vity in HCT116 MTAP del compared with HCT116 MTAP wild-type (WT) cells. MRTX1719 demonstrated dose-dependent antitumor activity and inhibition of PRMT5-dependent SDMA modification in MTAP del tumors. In contrast, MRTX1719 demonstrated minimal effects on SDMA and viability in MTAP WT tumor xenografts or hematopoietic cells. MRTX1719 demonstrated marked antitumor activity across a panel of xenograft models at well-tolerated doses. Early signs of clinical activity were observed including objective responses in patients with MTAP del melanoma, gallbladder adenocarcinoma, mesothelioma, non-small cell lung cancer, and malignant peripheral nerve sheath tumors from the phase I/II study. SIGNIFICANCE: PRMT5 was identified as a synthetic lethal target for MTAP del cancers; however, previous PRMT5 inhibitors do not selectively target this genotype. The differentiated binding mode of MRTX1719 leverages the elevated MTA in MTAP del cancers and represents a promising therapy for the ∼10% of patients with cancer with this biomarker. See related commentary by Mulvaney, p. 2310. This article is featured in Selected Articles from This Issue, p. 2293.

Artificial Intelligence (AI)-Aided Structure Optimization for Enhanced Gene Delivery: The Effect of the Polymer Component Distribution (PCD).

Gene therapy has emerged as a significant advancement in medicine in recent years. However, the development of effective gene delivery vectors, particularly polymer vectors, remains a significant challenge. Limited understanding of the internal structure of polymer vectors has hindered efforts to enhance their efficiency. This work focuses on investigating the impact of polymer structure on gene delivery, using the well-known polymeric vector poly(ß-amino ester) (PAE) as a case study. For the first time, we revealed the distinct characteristics of individual polymer components and their synergistic effects-the appropriate combination of different components within a polymer (high MW and low MW components) on gene delivery. Additionally, artificial intelligence (AI) analysis was employed to decipher the relationship between the polymer component distribution (PCD) and gene transfection performance. Guided by this analysis, a series of highly efficient polymer vectors that outperform current commercial reagents such as jetPEI and Lipo3000 were developed, among which the transfection efficiency of the PAE-B1-based polyplex was approximately 1.5 times that of Lipo3000 and 2 times that of jetPEI in U251 cells.