The Immune-Related 27-Gene Signature DetermaIO Predicts Response to Neoadjuvant Atezolizumab plus Chemotherapy in Triple-Negative Breast Cancer.

PURPOSE: We assessed the 27-gene RT-qPCR-based DetermaIO assay and the same score calculated from RNA sequencing (RNA-seq) data as predictors of sensitivity to immune checkpoint therapy in the neoTRIPaPDL1 randomized trial that compared neoadjuvant carboplatin/nab-paclitaxel chemotherapy (CT) plus atezolizumab with CT alone in stage II/III triple-negative breast cancer. We also assessed the predictive function of the immuno-oncology (IO) score in expression data of patients treated with pembrolizumab plus paclitaxel (N = 29) or CT alone (N = 56) in the I-SPY2 trial. EXPERIMENTAL DESIGN: RNA-seq data were obtained from pretreatment core biopsies from 242 (93.8%) of the 258 patients in the per-protocol-population. The DetermaIO RT-qPCR test, performed in the CAP/CLIA-accredited laboratory of Oncocyte Corp., was available for 220 patients (85.3%). A previously established threshold was used to assign DetermaIO-positive versus DetermaIO-negative status. Publicly available microarray data were used from I-SPY2. RESULTS: IO scores calculated from RNA-seq and RT-qPCR data were highly concordant. In neoTRIPaPDL1, DetermaIO-positive cancers (N = 92, 41.8%) had pathologic complete response (pCR) rates of 69.8% and 46.9% in the CT + atezolizumab and CT arms, respectively. In DetermaIO-negative cases, pCR rates were similar in both arms (44.6% vs. 49.2%; interaction test P = 0.04). PDL1 protein expression and stromal tumor-infiltrating lymphocyte count were not predictive of differential benefit from atezolizumab. In I-SPY2, IO-positive cancers (45.9%) had pCR rates of 85.7% and 16%, with and without immunotherapy, respectively. In IO-negative cancers, pCR rates were 46.7% versus 16.1%. CONCLUSIONS: DetermaIO identified patients who benefited from neoadjuvant immunotherapy resulting in improved pCR rate, independently of PDL1.

Datopotamab-deruxtecan in early-stage breast cancer: the sequential multiple assignment randomized I-SPY2.2 phase 2 trial.

Among the goals of patient-centric care are the advancement of effective personalized treatment, while minimizing toxicity. The phase 2 I-SPY2.2 trial uses a neoadjuvant sequential therapy approach in breast cancer to further these goals, testing promising new agents while optimizing individual outcomes. Here we tested datopotamab-deruxtecan (Dato-DXd) in the I-SPY2.2 trial for patients with high-risk stage 2/3 breast cancer. I-SPY2.2 uses a sequential multiple assignment randomization trial design that includes three sequential blocks of biologically targeted neoadjuvant treatment: the experimental agent(s) (block A), a taxane-based regimen tailored to the tumor subtype (block B) and doxorubicin-cyclophosphamide (block C). Patients are randomized into arms consisting of different investigational block A treatments. Algorithms based on magnetic resonance imaging and core biopsy guide treatment redirection after each block, including the option of early surgical resection in patients predicted to have a high likelihood of pathological complete response, the primary endpoint. There are two primary efficacy analyses: after block A and across all blocks for the six prespecified breast cancer subtypes (defined by clinical hormone receptor/human epidermal growth factor receptor 2 (HER2) status and/or the response-predictive subtypes). We report results of 103 patients treated with Dato-DXd. While Dato-DXd did not meet the prespecified threshold for success (graduation) after block A in any subtype, the treatment strategy across all blocks graduated in the hormone receptor-negative HER2-Immune-DNA repair deficiency- subtype with an estimated pathological complete response rate of 41%. No new toxicities were observed, with stomatitis and ocular events occurring at low grades. Dato-DXd was particularly active in the hormone receptor-negative/HER2-Immune-DNA repair deficiency- signature, warranting further investigation, and was safe in other subtypes in patients who followed the treatment strategy. ClinicalTrials.gov registration: NCT01042379 .

Overall Survival with Pembrolizumab in Early-Stage Triple-Negative Breast Cancer.

BACKGROUND: In patients with early-stage triple-negative breast cancer, the phase 3 KEYNOTE-522 trial showed significant improvements in pathological complete response and event-free survival with the addition of pembrolizumab to platinum-containing chemotherapy. Here we report the final results for overall survival. METHODS: We randomly assigned, in a 2:1 ratio, patients with previously untreated stage II or III triple-negative breast cancer to receive neoadjuvant therapy with four cycles of pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks plus paclitaxel and carboplatin, followed by four cycles of pembrolizumab or placebo plus doxorubicin-cyclophosphamide or epirubicin-cyclophosphamide. After definitive surgery, patients received adjuvant pembrolizumab (pembrolizumab-chemotherapy group) or placebo (placebo-chemotherapy group) every 3 weeks for up to nine cycles. The primary end points were pathological complete response and event-free survival. Overall survival was a secondary end point. RESULTS: Of the 1174 patients who underwent randomization, 784 were assigned to the pembrolizumab-chemotherapy group and 390 to the placebo-chemotherapy group. At the data-cutoff date (March 22, 2024), the median follow-up was 75.1 months (range, 65.9 to 84.0). The estimated overall survival at 60 months was 86.6% (95% confidence interval [CI], 84.0 to 88.8) in the pembrolizumab-chemotherapy group, as compared with 81.7% (95% CI, 77.5 to 85.2) in the placebo-chemotherapy group (P = 0.002). Adverse events were consistent with the established safety profiles of pembrolizumab and chemotherapy. CONCLUSIONS: Neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab resulted in a significant improvement, as compared with neoadjuvant chemotherapy alone, in overall survival among patients with early-stage triple-negative breast cancer. (Funded by Merck Sharp and Dohme, a subsidiary of Merck [Rahway, NJ]; KEYNOTE-522 ClinicalTrials.gov number, NCT03036488.).

Phosphoenolpyruvate carboxykinase-2 (PCK2) is a therapeutic target in triple-negative breast cancer.

PURPOSE: Metabolic rewiring in malignant transformation is often accompanied by altered expression of metabolic isozymes. Phosphoenolpyruvate carboxykinase-2 (PCK2) catalyzes the rate-limiting step of gluconeogenesis and is the dominant isoform in many cancers including triple-negative breast cancer (TNBC). Our goal was to identify small molecule inhibitors of PCK2 enzyme activity. METHODS: We assessed the impact of PCK2 down regulation with shRNA on TNBC cell growth in vitro and used AtomNet® deep convolutional neural network software to identify potential small molecule inhibitors of PCK2-based structure. We iteratively tested candidate compounds in an in vitro PCK-2 enzyme assay. The impact of the top hit on metabolic flux and cell viability was also assessed. RESULTS: PCK2 downregulation decreased growth of BT-549 and MDA-MB-231 cells and reduced metabolic flux through pyruvate carboxylase. The first AtomNet® in silico structural screen of 7 million compounds yielded 86 structures that were tested in PCK2 enzyme assay in vitro. The top hit (IC50 = 2.4 µM) was used to refine a second round of in silico screen that yielded 82 candidates to be tested in vitro, which resulted in 45 molecules with inhibition > 20%. In the second in vitro screen we also included 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate, previously suggested to be PCK2 inhibitor based on structure, which emerged as the top hit. The specificity of this compound was tested in PCK1 and PCK2 enzymatic assays and showed IC50 of 500 nM and 3.5-27 nM for PCK1 and PCK2, respectively. CONCLUSION: 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate is a high affinity PCK2 enzyme inhibitor that also has significant growth inhibitory activity in breast cell lines in vitro and represents a potential therapeutic lead compound.

Completion Rate and Positive Results Reporting Among Immunotherapy Trials in Breast Cancer, 2004-2023.

Importance: Clinical trials are the path to test and introduce new therapies in the clinic. Trials that are unable to produce results represent inefficiency in the system and may also undermine patient confidence in the new drug development process. Objectives: To survey the immunotherapy clinical trial landscape of breast cancer between January 2004 and April 2023 and examine what fraction of trials with primary completion date up to November 30, 2022, failed to report outcome, assessing the proportion of trials that yielded positive results and describing trial features associated with these 2 outcomes. Design, Setting, and Participants: This cross-sectional study included breast cancer immunotherapy trials identified in ClinicalTrials.gov. Trial details and results were retrieved in December 2023. Google Scholar, PubMed, and LARVOL CLIN websites were also searched for reports. Main Outcomes and Measures: Trial outcome reported as abstract or manuscript. Reported trials were categorized as positive (ie, met its end point) or negative. Association between reporting and trial features were tested using Fisher exact test. Results: A total of 331 immuno-oncology trials were initiated in breast cancer by April 2023; 242 trials were phase II, 47 were phase I, and 42 phase III. By setting, 212 studies (64.0%) were conducted in metastatic, 94 (28.4%) in neoadjuvant, and 25 (7.6%) in adjuvant settings. Among phase II and III trials, 168 (59.2%) were nonrandomized. One hundred twenty trials had primary completion dates up to November 30, 2022, of which 30 (25.0%; enrolling a combined 2428 patients) failed to report their outcomes; 7 phase I trials (31.8%), 21 phase II trials (23.6%), and 2 phase III trials (22.2%) were unreported. Single-center studies were significantly more likely to be unreported than multicenter studies (19 of 54 [35.2%] vs 9 of 60 [15.0%]; P = .02). Of the 90 reported trials, 47 (52.2%) and 43 (47.8%) were positive and negative, respectively. Seventeen of 19 (89.5%) of the reported randomized trials (accruing a total of 4189 patients) were negative. Conclusions and Relevance: In this cross-sectional study of immunotherapy breast cancer trials, the large number of trials yielded modest clinical impact. Single-center trials commonly failed to report their outcomes and many phase II studies have not translated into corresponding successful phase III trials.

Peripheral blood immune parameters, response, and adverse events after neoadjuvant chemotherapy plus durvalumab in early-stage triple-negative breast cancer.

PURPOSE: We evaluated T- and B-cell receptor (TCR and BCR) repertoire diversity and 38 serum cytokines in pre- and post-treatment peripheral blood of 66 patients with triple-negative breast cancer (TNBC) who received neoadjuvant chemotherapy plus durvalumab and assessed associations with pathologic response and immune-related adverse events (irAEs) during treatment. METHODS: Genomic DNA was isolated from buffy coat for TCR and BCR clonotype profiling using the Immunoseq platform and diversity was quantified with Pielou's evenness index. MILLIPLEX MAP Human Cytokine/Chemokine Magnetic Bead Panel was used to measure serum cytokine levels, which were compared between groups using moderated t-statistic with Benjamini-Hochberg correction for multiple testing. RESULTS: TCR and BCR diversity was high (Pielou's index > 0.75) in all samples. Baseline receptor diversities and change in diversity pre- and post-treatment were not associated with pathologic response or irAE status, except for BCR diversity that was significantly lower post-treatment in patients who developed irAE (unadjusted p = 0.0321). Five cytokines increased after treatment in patients with pathologic complete response (pCR) but decreased in patients with RD, most prominently IL-8. IFNγ, IL-7, and GM-CSF levels were higher in pre-treatment than in post-treatment samples of patients who developed irAEs but were lower in those without irAEs. CONCLUSION: Baseline peripheral blood cytokine levels may predict irAEs in patients treated with immune checkpoint inhibitors and chemotherapy, and increased post-treatment B-cell clonal expansion might mediate irAEs.

Phase III Randomized, Placebo-Controlled Trial of Endocrine Therapy ± 1 Year of Everolimus in Patients With High-Risk, Hormone Receptor-Positive, Early-Stage Breast Cancer.

PURPOSE: Phosphatidylinositol 3-kinase/AKT-serine threonine kinase/mammalian target of rapamycin (mTOR) pathway abnormalities contribute to endocrine resistance. Everolimus, an mTOR inhibitor, improved progression-free survival in hormone receptor-positive metastatic breast cancer (BC) when combined with endocrine therapy (ET). In this phase III randomized, placebo-controlled trial, we assessed the efficacy of everolimus + ET as adjuvant therapy in high-risk, hormone receptor-positive, human epidermal growth factor receptor 2-negative BC after adjuvant/neoadjuvant chemotherapy. METHODS: Patients were randomly assigned 1:1 to physician's choice ET and 1 year of everolimus (10 mg orally once daily) or placebo stratified by risk group. The primary end point was invasive disease-free survival (IDFS) evaluated by a stratified log-rank test with the hazard ratio (HR) estimated by Cox regression. Subset analyses included preplanned evaluation by risk group and exploratory analyses by menopausal status and age. Secondary end points included overall survival (OS) and safety. Everolimus did not improve IDFS/OS when added to ET in patients with early-stage high-risk, hormone receptor-positive BC. RESULTS: One thousand and nine hundred thirty-nine patients were randomly assigned with 1,792 eligible for analysis. Overall, no benefit of everolimus was seen for IDFS (HR, 0.94 [95% CI, 0.77 to 1.14]) or OS (HR, 0.97 [95% CI, 0.75 to 1.26]). The assumption of proportional hazards was not met suggesting significant variability in the HR over time since the start of treatment. In an unplanned subgroup analysis among postmenopausal patients (N = 1,221), no difference in IDFS (HR, 1.08 [95% CI, 0.86 to 1.36]) or OS (HR, 1.19 [95% CI, 0.89 to 1.60]) was seen. In premenopausal patients (N = 571), everolimus improved both IDFS (HR, 0.64 [95% CI, 0.44 to 0.94]) and OS (HR, 0.49 [95% CI, 0.28 to 0.86]). Treatment completion rates were lower in the everolimus arm compared with placebo (48% v 73%) with higher grade 3 and 4 adverse events (35% v 7%). CONCLUSION: One year of adjuvant everolimus + ET did not improve overall outcomes. Subset analysis suggests mTOR inhibition as a possible target for patients who remain premenopausal after chemotherapy.

Neoadjuvant pembrolizumab+chemotherapy/adjuvant pembrolizumab for Early-Stage Triple-Negative breast cancer: Quality-of-Life results from randomized KEYNOTE-522 study.

BACKGROUND: In KEYNOTE-522 (NCT03036488), neoadjuvant pembrolizumab+chemotherapy then adjuvant pembrolizumab significantly improved pathological complete response and event-free survival vs neoadjuvant chemotherapy in early-stage triple-negative breast cancer (TNBC). We report patient-reported outcomes (PROs) from KEYNOTE-522. METHODS: Patients were randomized 2:1 to neoadjuvant pembrolizumab 200 mg or placebo every 3 weeks, plus 4 cycles of paclitaxel+carboplatin then 4 cycles of doxorubicin (or epirubicin)+cyclophosphamide. After surgery, patients received adjuvant pembrolizumab or placebo for up to 9 cycles. EORTC QLQ-30 and QLQ-BR23 were prespecified secondary objectives. Between-group differences in least squares (LS) mean change from baseline (day 1/cycle 1 in both neoadjuvant and adjuvant phases) to the prespecified latest time point with ≥60%/80% completion/compliance were assessed using a longitudinal model (no alpha error assigned). RESULTS: Week 21 (neoadjuvant phase) and week 24 (adjuvant phase) were the latest time points at which completion/compliance rates were ≥60%/80%. In the neoadjuvant phase, between-group differences (pembrolizumab+chemotherapy [N = 762] vs placebo+chemotherapy [N = 383]) in LS mean change from baseline to week 21 in QLQ-C30 GHS/QoL, emotional functioning, and physical functioning were -1.04 (95% CI, -3.46 to 1.38), -0.69 (95% CI, -3.13 to 1.75), and -2.85 (95% CI, -5.11 to - 0.60), respectively. In the adjuvant phase, between-group differences (pembrolizumab [N = 539] vs placebo [N = 308]) in LS mean change from baseline to week 24 were -0.41 (95% CI, -2.60 to 1.77), -0.60 (95% CI, -2.99 to 1.79), and -1.57 (95% CI, -3.36 to 0.21). CONCLUSIONS: No substantial differences in PRO assessments were observed between neoadjuvant pembrolizumab+chemotherapy followed by adjuvant pembrolizumab vs neoadjuvant placebo+chemotherapy in early-stage TNBC. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03036488.

Pre-treatment amino acids and risk of paclitaxel-induced peripheral neuropathy in SWOG S0221.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a treatment-limiting and debilitating neurotoxicity of many commonly used anti-cancer agents, including paclitaxel. The objective of this study was to confirm the previously found inverse association between pre-treatment blood concentrations of histidine and CIPN occurrence and examine relationships of other amino acids with CIPN severity. METHODS: Pre-treatment serum concentrations of 20 amino acids were measured in the SWOG S0221 (NCT00070564) trial of patients with early-stage breast cancer receiving paclitaxel. The associations between amino acids and CIPN severity were tested in regression analysis adjusted for paclitaxel schedule, age, self-reported race, and body mass index with Bonferroni correction. The network of metabolic pathways of amino acids was analyzed using over-representation analysis. The partial correlation network of amino acids was evaluated using a debiased sparse partial correlation algorithm. RESULTS: In the primary analysis, histidine concentration was not associated with CIPN occurrence (odds ratio (OR) = 0.97 [0.83, 1.13], p = 0.72). In secondary analyses, higher concentrations of four amino acids, glutamate (ß = 0.58 [0.23, 0.93], p = 0.001), phenylalanine (ß = 0.54 [0.19, 0.89], p = 0.002), tyrosine (ß = 0.57 [0.23, 0.91], p = 0.001), and valine (ß = 0.58 [0.24, 0.92], p = 0.001) were associated with more severe CIPN, but none of these associations retained significance after adjustment. In the over-representation analysis, no amino acid metabolic pathways were significantly enriched (all FDR > 0.05). In the network of enriched pathways, glutamate metabolism had the highest centrality. CONCLUSIONS: This analysis showed that pre-treatment serum amino acid concentrations are not strongly predictive of CIPN severity. Prospectively designed studies that assess non-amino acid metabolomics predictors are encouraged.

Navigating practical challenges in immunotherapy for metastatic triple negative breast cancer.

Immunotherapy has revolutionized cancer therapy and now represents a standard of care for many tumor types, including triple-negative breast cancer. Despite the positive results that have led to the approval of immunotherapy in both early- and advanced-stage triple-negative breast cancer, pivotal clinical trials cannot address the myriad questions arising in everyday clinical practice, often falling short in delivering all the information that clinicians require. In this manuscript, we aim to address some of these practical questions, with the purpose of providing clinicians with a guide for optimizing the use of immune checkpoint inhibitors in the management of breast cancer patients and identifying opportunities for future research to clarify unresolved questions.

TROPION-Breast03: a randomized phase III global trial of datopotamab deruxtecan ± durvalumab in patients with triple-negative breast cancer and residual invasive disease at surgical resection after neoadjuvant therapy.

Background: Despite advances in the treatment of early triple-negative breast cancer (TNBC), patients with residual invasive disease after neoadjuvant therapy have a high risk of disease recurrence and worse survival outcomes than those who have pathological complete response (pCR). Improving outcomes in early TNBC remains an unmet need requiring new adjuvant treatment approaches. Datopotamab deruxtecan (Dato-DXd) is an antibody-drug conjugate comprising a humanized anti-trophoblast cell-surface antigen 2 immunoglobulin G1 (IgG1) monoclonal antibody attached via a plasma-stable, cleavable linker to a potent topoisomerase I inhibitor payload, with activity observed in advanced TNBC. Objectives: TROPION-Breast03 is an ongoing phase III study evaluating the efficacy and safety of Dato-DXd alone or combined with durvalumab versus standard-of-care therapy as adjuvant treatment in patients with stage I-III TNBC with residual invasive disease at surgical resection following neoadjuvant treatment. Methods and design: Eligible patients, aged ⩾18 years, will be randomized in a 2:1:2 ratio to receive Dato-DXd [6 mg/kg intravenously (IV) every 3 weeks (Q3W); eight cycles] and durvalumab (1120 mg IV Q3W; nine cycles), Dato-DXd monotherapy (6 mg/kg IV Q3W), or investigator's choice of therapy (ICT; capecitabine, pembrolizumab, or capecitabine and pembrolizumab). The primary endpoint is invasive disease-free survival (iDFS) for Dato-DXd and durvalumab versus ICT. Key secondary endpoints include safety, distant disease-free survival, and overall survival for Dato-DXd and durvalumab versus ICT and iDFS for Dato-DXd monotherapy versus ICT. Ethics: TROPION-Breast03 will be approved by the independent ethics committees or institutional review boards at each study site. All study participants will provide written informed consent. Discussion: TROPION-Breast03 will help define the potential role of Dato-DXd in the treatment of patients with early-stage TNBC who do not have pCR after neoadjuvant therapy. Trial registration: ClinicalTrials.gov identifier: NCT05629585 (registration date: 29 November 2022).

TROPION-Breast03: a clinical trial designed to assess the effectiveness and safety of Dato-DXd, alone or in combination with durvalumab, in patients with triple-negative breast cancer who have cancer cells remaining at the time of surgery after initial systemic therapy Triple-negative breast cancer (TNBC), in which cells do not have estrogen or progesterone receptors or high levels of human epidermal growth factor receptor 2, is the most aggressive breast cancer subtype. TNBC is difficult to treat and associated with high risk of recurrence despite standard systemic therapy (treatment targeting the entire body), which can include chemotherapy alone or in combination with immunotherapy (treatment targeting the immune system). To reduce the risk of recurrence, standard systemic treatment is often followed by surgical removal of the patient's tumors and additional systemic treatment. Dato-DXd is an antibody-drug conjugate, which is an anticancer drug (DXd) connected to an antibody (datopotamab) by a stable linker. Datopotamab binds to TROP2, a protein found on breast cancer cells, and is taken into the tumor cell where the linker breaks, releasing DXd to kill the cell. By delivering DXd directly to cancer cells, Dato-DXd reduces exposure in the rest of the body, reducing the risk of side effects. Since Dato-DXd can recruit immune cells to cancer sites, it may work better combined with durvalumab, a drug that blocks the activity of a protein called PD-L1, making cancer cells more susceptible to being killed by immune cells. The TROPION-Breast03 study will compare Dato-DXd, alone or combined with durvalumab, with standard-of-care therapy in patients with TNBC that has not spread to parts of the body away from the original tumor site(s), but with cancer cells remaining at the time of surgery after initial systemic therapy. It will assess how well each treatment works and describe any side effects. We plan to recruit 1,075 eligible adults who will be randomly assigned in a 2:1:2 ratio to: • Dato-DXd + durvalumab • Dato-DXd alone • Standard-of-care therapy • Patients will receive treatment until they complete the planned course of therapy (8 or 9 cycles), their cancer returns, side effects become unacceptable, or they choose to stop.

Core Needle Biopsies as an Alternative Source for Ex Vivo Expanded TIL for Adoptive Cell Therapy in Triple-Negative Breast Cancer.

Adoptive transfer of ex vivo expanded tumor-infiltrating lymphocytes (TILs) have produced long-term response in metastatic cancers. TILs have traditionally been expanded from surgically resected specimens. Ultrasound-guided core needle biopsy (CNB) is an alternative method that avoids the morbidity of surgery and have added benefits which may include patients not amenable to surgery as well as the potential to produce TILs from multiple lesions in the same patient. We assessed the ability to produce and expand TILs from primary triple-negative breast cancer tumors from CNB (n=7) and demonstrate comparable expansion, phenotype and cytokine secretion after phorbol myristate acetate-ionomycin stimulation to TILs expanded from surgery (n=6). T cell Receptor clonality and diversity were also comparable between the two cohorts throughout the TIL culture. CNB is a safe and feasible method to obtain tumor tissue for TIL generation in patients with triple-negative breast cancer.

Neoadjuvant Trebananib plus Paclitaxel-based Chemotherapy for Stage II/III Breast Cancer in the Adaptively Randomized I-SPY2 Trial-Efficacy and Biomarker Discovery.

PURPOSE: The neutralizing peptibody trebananib prevents angiopoietin-1 and angiopoietin-2 from binding with Tie2 receptors, inhibiting angiogenesis and proliferation. Trebananib was combined with paclitaxel±trastuzumab in the I-SPY2 breast cancer trial. PATIENTS AND METHODS: I-SPY2, a phase II neoadjuvant trial, adaptively randomizes patients with high-risk, early-stage breast cancer to one of several experimental therapies or control based on receptor subtypes as defined by hormone receptor (HR) and HER2 status and MammaPrint risk (MP1, MP2). The primary endpoint is pathologic complete response (pCR). A therapy "graduates" if/when it achieves 85% Bayesian probability of success in a phase III trial within a given subtype. Patients received weekly paclitaxel (plus trastuzumab if HER2-positive) without (control) or with weekly intravenous trebananib, followed by doxorubicin/cyclophosphamide and surgery. Pathway-specific biomarkers were assessed for response prediction. RESULTS: There were 134 participants randomized to trebananib and 133 to control. Although trebananib did not graduate in any signature [phase III probabilities: Hazard ratio (HR)-negative (78%), HR-negative/HER2-positive (74%), HR-negative/HER2-negative (77%), and MP2 (79%)], it demonstrated high probability of superior pCR rates over control (92%-99%) among these subtypes. Trebananib improved 3-year event-free survival (HR 0.67), with no significant increase in adverse events. Activation levels of the Tie2 receptor and downstream signaling partners predicted trebananib response in HER2-positive disease; high expression of a CD8 T-cell gene signature predicted response in HR-negative/HER2-negative disease. CONCLUSIONS: The angiopoietin (Ang)/Tie2 axis inhibitor trebananib combined with standard neoadjuvant therapy increased estimated pCR rates across HR-negative and MP2 subtypes, with probabilities of superiority >90%. Further study of Ang/Tie2 receptor axis inhibitors in validated, biomarker-predicted sensitive subtypes is warranted.

Race, Gene Expression Signatures, and Clinical Outcomes of Patients With High-Risk Early Breast Cancer.

Importance: There has been little consideration of genomic risk of recurrence by breast cancer subtype despite evidence of racial disparities in breast cancer outcomes. Objective: To evaluate associations between clinical trial end points, namely pathologic complete response (pCR) and distant recurrence-free survival (DRFS), and race and examine whether gene expression signatures are associated with outcomes by race. Design, Setting, and Participants: This retrospective cohort study used data from the Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis 2 (I-SPY 2) multicenter clinical trial of neoadjuvant chemotherapy with novel agents and combinations for patients with previously untreated stage II/III breast cancer. Analyses were conducted of associations between race and short- and long-term outcomes, overall and by receptor subtypes, and their association with 28 expression biomarkers. The trial enrolled 990 female patients between March 30, 2010, and November 5, 2016, with a primary tumor size of 2.5 cm or greater and clinical or molecular high risk based on MammaPrint or hormone receptor (HR)-negative/ERBB2 (formerly HER2 or HER2/neu)-positive subtyping across 9 arms. This data analysis was performed between June 10, 2021, and October 20, 2022. Exposure: Race, tumor receptor subtypes, and genomic biomarker expression of early breast cancer. Main Outcomes and Measures: The primary outcomes were pCR and DRFS assessed by race, overall, and by tumor subtype using logistic regression and Cox proportional hazards regression models. The interaction between 28 expression biomarkers and race, considering pCR and DRFS overall and within subtypes, was also evaluated. Results: The analytic sample included 974 participants (excluding 16 self-reporting as American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, or multiple races due to small sample sizes), including 68 Asian (7%), 120 Black (12%), and 786 White (81%) patients. Median (range) age at diagnosis was 47 (25-71) years for Asian, 49 (25-77) for Black, and 49 (23-73) years for White patients. The pCR rates were 32% (n = 22) for Asian, 30% for Black (n = 36), and 32% for White (n = 255) patients (P = .87). Black patients with HR-positive/ERBB2-negative tumors not achieving pCR had significantly worse DRFS than their White counterparts (hazard ratio, 2.28; 95% CI, 1.24-4.21; P = .01), with 5-year DRFS rates of 55% (n = 32) and 77% (n = 247), respectively. Black patients with HR-positive/ERBB2-negative tumors, compared with White patients, had higher expression of an interferon signature (mean [SD], 0.39 [0.87] and -0.10 [0.99]; P = .007) and, compared with Asian patients, had a higher mitotic score (mean [SD], 0.07 [1.08] and -0.69 [1.06]; P = .01) and lower estrogen receptor/progesterone receptor signature (mean [SD], 0.31 [0.90] and 1.08 [0.95]; P = .008). A transforming growth factor ß signature had a significant association with race relative to pCR and DRFS, with a higher signature associated with lower pCR and worse DRFS outcomes among Black patients only. Conclusions and Relevance: The findings show that women with early high-risk breast cancer who achieve pCR have similarly good outcomes regardless of race, but Black women with HR-positive/ERBB2-negative tumors without pCR may have worse DRFS than White women, highlighting the need to develop and test novel biomarker-informed therapies in diverse populations.

Pan-cancer analysis of antibody-drug conjugate targets and putative predictors of treatment response.

BACKGROUND: Antibody-drug conjugates (ADCs) are a rapidly expanding class of compounds in oncology. Our goal was to assess the expression of ADC targets and potential downstream determining factors of activity across pan-cancer and normal tissues. MATERIALS AND METHODS: ADCs in clinical trials (n = 121) were identified through ClinicalTrials.gov, corresponding to 54 targets. Genes potentially implicated in treatment response were identified in the literature. Gene expression from The Cancer Genome Atlas (9000+ cancers of 31 cancer types), the Genotype-Tissue Expression database (n = 19,000 samples from 31 normal tissue types), and the TNMplot.com (n = 12,494 unmatched primary and metastatic samples) were used in this analysis. To compare relative expression across and within tumour types we used pooled normal tissues as reference. RESULTS: For most ADC targets, mRNA levels correlated with protein expression. Pan-cancer target expression distributions identified appealing cancer types for each ADC development. Co-expression of multiple targets was common and suggested opportunities for ADC combinations. Expression levels of genes potentially implicated in ADC response downstream of the target might provide additional information (e.g. TOP1 was highly expressed in many tumour types, including breast and lung cancers). Metastatic compared to primary tissues overexpressed some ADCs targets. Single sample "targetgram" plots were generated to visualise the expression of potentially competing ADC targets and resistance/sensitivity markers highlighting high inter-patient heterogeneity. Off-cancer target expression only partially explains adverse events, while expression of determinants of payload activity explained more of the observed toxicities. CONCLUSION: Our findings draw attention to new therapeutic opportunities for ADCs that can be tested in the clinic and our web platform (https://tnmplot.com) can assist in prioritising upcoming ADC targets for clinical development.

Breast cancers with high proliferation and low ER-related signalling have poor prognosis and unique molecular features with implications for therapy.

BACKGROUND: Luminal breast cancers with high proliferation (MKShi) and low ER-related signalling (ERSlo) have a poor prognosis. We investigated treatment responses and molecular features of MKShi/ERSlo tumours to inform potential therapies. METHODS: Gene expression data from patients who received neoadjuvant chemotherapy (NAC) without (MDACC, N = 199) or with pembrolizumab (I-SPY2, N = 40), or endocrine therapy (NET) without (POETIC, N = 172) or with palbociclib (NeoPalAna, N = 32) were analyzed to assess treatment response by MKS/ERS-subgroups. TCGA was used to assess the mutational landscape and biomarkers associated with palbociclib-resistance (Cyclin-E, RBsig, IRPR) and immunotherapy-response (TMB, TILs, T-cell inflamed) by MKS/ERS-subgroups. RESULTS: Compared to MKShi/ERShi tumours, MKShi/ERSlo tumours had higher pathological response rates to NAC (22% vs 8%, p = 0.06) but a higher recurrence risk (4-year metastasis-free survival 70% vs 94%, p = 0.01). MKShi/ERSlo tumours frequently harboured TP53 (34%) and PIK3CA (33%) mutations, and showed high expression of Cyclin-E, RBsig and IRPR, high TMB and elevated TIL and T-cell inflamed metagene expression. MKShi/ERSlo tumours retained high proliferation after NET with or without palbociclib but had higher pathological complete response rates when pembrolizumab was added to NAC (42% vs 21%, p = 0.07). CONCLUSIONS: MKShi/ERSlo tumours have dismal outcomes and are enriched in chemotherapy-sensitive but ET- and palbociclib-resistant tumours. Biomarker analysis and clinical data suggest a potential role for immunotherapy in this group.

Dual Prognostic Classification of Triple-Negative Breast Cancer by DNA Damage Immune Response and Homologous Recombination Deficiency.

PURPOSE: Triple-negative breast cancer (TNBC) is a heterogeneous disease. We previously showed that homologous recombination deficiency (HRD) and the DNA damage immune response (DDIR) signature are prognostic in TNBC. We hypothesized that these biomarkers reflect related but not completely interdependent biological processes, that their combined use would be prognostic, and that simultaneous assessment of the immunologic microenvironment and susceptibility to DNA damaging therapies might be able to identify subgroups with distinct therapeutic vulnerabilities. METHODS: We analyzed the dual DDIR/HRD classification in 341 patients with TNBC treated with adjuvant anthracycline-based chemotherapy on the SWOG S9313 trial and corroborated our findings in The Cancer Genome Atlas breast cancer data set. RESULTS: DDIR/HRD classification is highly prognostic in TNBC and identifies biologically and immunologically distinct subgroups. Immune-enriched DDIR+/HRD+ TNBCs have the most favorable prognosis, and DDIR+/HRD- and DDIR-/HRD+ TNBCs have favorable intermediate prognosis, despite the latter being immune-depleted. DDIR-/HRD- TNBCs have the worst prognosis and represent an internally heterogeneous group of immune-depleted chemoresistant tumors. CONCLUSION: Our findings propose DDIR/HRD classification as a potentially clinically relevant approach to categorize tumors on the basis of therapeutic vulnerabilities.

Pembrolizumab Plus Chemotherapy Followed by Pembrolizumab in Patients With Early Triple-Negative Breast Cancer: A Secondary Analysis of a Randomized Clinical Trial.

Importance: In the phase 3 KEYNOTE-522 study, addition of pembrolizumab to neoadjuvant chemotherapy followed by adjuvant pembrolizumab significantly increased pathologic complete response (pCR) and event-free survival (EFS) vs neoadjuvant chemotherapy in patients with early triple-negative breast cancer. Objective: To evaluate efficacy and safety outcomes for patients enrolled in East/Southeast Asia (Asia) in KEYNOTE-522. Design, Setting, and Participants: KEYNOTE-522, a multicenter, double-blind, randomized clinical trial, enrolled 1174 patients between March 7, 2017, and September 13, 2018. For interim EFS and overall survival (OS) analyses (data cutoff, March 23, 2021), median follow-up was 39.8 months (range, 30.4-46.9 months) for pembrolizumab plus chemotherapy and 40.8 months (range, 30.1-46.9 months) for placebo plus chemotherapy. Data cutoff for pCR analysis was September 24, 2018. This secondary analysis included adults enrolled in Asia with newly diagnosed, previously untreated, nonmetastatic triple-negative breast cancer (tumor stage T1c and nodal stage N1-2 or tumor stage T2-4 and nodal stage N0-2) and Eastern Cooperative Oncology Group performance status of 0 to 1, regardless of programmed cell death ligand 1 (PD-L1) status. Intervention: Patients were randomized 2:1 to 4 cycles of pembrolizumab (200 mg every 3 weeks) or placebo plus carboplatin and paclitaxel and another 4 cycles of pembrolizumab or placebo plus doxorubicin or epirubicin and cyclophosphamide before surgery. After definitive surgery, patients received pembrolizumab or placebo every 3 weeks for 9 cycles or until recurrence or unacceptable toxic effects. Main Outcomes and Measures: The main outcome was pCR (no evidence of primary tumor after neoadjuvant therapy or carcinoma in situ after neoadjuvant therapy and no regional lymph node involvement after neoadjuvant therapy) at the time of definitive surgery and EFS. Results: A total of 216 of 1174 randomized patients (all female; median [range] age, 46.0 [24.0-71.0] years) were from Korea, Japan, Taiwan, and Singapore (136 in the pembrolizumab plus chemotherapy group and 80 in the placebo plus chemotherapy group). Of these patients, 104 (76.5%) in the pembrolizumab plus chemotherapy group and 60 (75.0%) in the placebo plus chemotherapy group had a tumor PD-L1 combined positive score of 1 or greater. Pathologic complete response was 58.7% (95% CI, 46.7%-69.9%) with pembrolizumab plus chemotherapy and 40.0% (95% CI, 26.4%-54.8%) with placebo plus chemotherapy; benefit was observed regardless of PD-L1 status. Thirteen patients (9.6%) in the pembrolizumab plus chemotherapy group and 20 patients (25.0%) in the placebo plus chemotherapy group had EFS events (hazard ratio, 0.35; 95% CI, 0.17-0.71). The 36-month EFS rate was 91.2% (95% CI, 85.0%-94.9%) with pembrolizumab plus chemotherapy and 77.2% (95% CI, 66.3%-85.0%) with placebo plus chemotherapy. Grade 3 to 4 treatment-related adverse events occurred in 109 patients (80.1%) receiving pembrolizumab plus chemotherapy and 64 patients (81.0%) receiving placebo plus chemotherapy. Conclusions and Relevance: In this subgroup analysis of patients enrolled in Asia in KEYNOTE-522, neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab led to clinically meaningful improvements in pCR and EFS vs neoadjuvant chemotherapy alone. These findings support the use of neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab as a standard-of-care therapy for patients in Asian countries with early triple-negative breast cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT03036488.