Efficacy, safety, and patient-reported outcomes across young to older age groups of patients with HR+/HER2- advanced breast cancer treated with ribociclib plus endocrine therapy in the randomized MONALEESA-2, -3, and -7 trials.

Background: Ribociclib + endocrine therapy (ET) showed significant progression-free survival (PFS) and overall survival (OS) benefits in the MONALEESA trials in patients with HR+ /HER2 - advanced breast cancer (ABC). We report efficacy, safety, and patient-reported outcomes (PROs) across age groups, including older patients, in these trials.

Methods: Data from the MONALEESA-2, -3, and -7 trials for pre- and postmenopausal patients receiving first-line treatment for ABC were pooled and analyzed by age (<65y, 65-74y, and ≥75y).

Abemaciclib Plus Fulvestrant in Advanced Breast Cancer After Progression on CDK4/6 Inhibition: Results From the Phase III postMONARCH Trial.

Purpose: Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) combined with endocrine therapy (ET) are the standard first-line treatment for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC); however, disease progression occurs in almost all patients and additional treatment options are needed. Herein, we report outcomes of the postMONARCH trial investigating a switch in ET with/without CDK4/6 inhibition with abemaciclib after disease progression on CDK4/6i.

Methods: This double-blind, randomized phase III study enrolled patients with disease progression on previous CDK4/6i plus aromatase inhibitor as initial therapy for advanced disease or recurrence on/after adjuvant CDK4/6i + ET.

Race and Clinical Outcomes in Hormone Receptor-Positive, HER2-Negative, Node-Positive Breast Cancer in the Randomized RxPONDER Trial.

Background: The phase III RxPONDER trial has impacted treatment for node-positive(1-3), hormone receptor-positive, HER2-negative breast cancer with 21-gene recurrence score (RS) ≤ 25. We investigated how these findings apply to different racial and ethnic groups within the trial.

Methods: The trial randomized women to endocrine therapy (ET) or to chemotherapy plus ET.

Further Optimizing Care of Patients With Operable Hormone Receptor-Sensitive Breast Cancer.

Harmonized global collaborations are crucial to improving outcomes in hormone sensitive operable breast cancer.

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

Sequential adaptive trial designs can help accomplish the goals of personalized medicine, optimizing outcomes and avoiding unnecessary toxicity. Here we describe the results of incorporating a promising antibody-drug conjugate, datopotamab-deruxtecan (Dato-DXd) in combination with programmed cell death-ligand 1 inhibitor, durvalumab, as the first sequence of therapy in the I-SPY2.2 phase 2 neoadjuvant sequential multiple assignment randomization trial for high-risk stage 2/3 breast cancer.

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.

Datopotamab Deruxtecan Versus Chemotherapy in Previously Treated Inoperable/Metastatic Hormone Receptor-Positive Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer: Primary Results From TROPION-Breast01.

Purpose: The global, phase 3, open-label, randomized TROPION-Breast01 study assessed the trophoblast cell surface antigen 2-directed antibody-drug conjugate datopotamab deruxtecan (Dato-DXd) versus investigator's choice of chemotherapy (ICC) in hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) breast cancer.

Methods: Adult patients with inoperable/metastatic HR+/HER2‒ breast cancer, who had disease progression on endocrine therapy, for whom endocrine therapy was unsuitable, and had received one to two previous lines of chemotherapy in the inoperable/metastatic setting, were randomly assigned 1:1 to Dato-DXd (6 mg/kg once every 3 weeks) or ICC (eribulin/vinorelbine/capecitabine/gemcitabine). Dual primary end points were progression-free survival (PFS) by blinded independent central review (BICR) and overall survival (OS).

Tuning Immune-Cold Tumor by Suppressing USP10/B7-H4 Proteolytic Axis Reinvigorates Therapeutic Efficacy of ADCs.

Tuning immune-cold tumor hot has largely attracted attention to improve cancer treatment, including immunotherapy and antibody-drug conjugates (ADCs). Utilizing multiomic analyses and experimental validation, this work identifies a pivotal role for the USP10/B7-H4 proteolytic axis in mediating the interplay between tumor immune responses and ADC efficacy, particularly for sacituzumab govitecan (SG) in treating triple negative breast cancers (TNBCs). Mechanistically, the inhibition of autocrine motility factor receptor (AMFR)-mediated ubiquitylation of B7-H4 by the deubiquitinase USP10 leads to the stabilization of B7-H4, which suppresses tumor immune activity and reduces SG treatment effectiveness.

Precision therapeutics and emerging strategies for HR-positive metastatic breast cancer.

Anti-oestrogen-based therapies, often combined with a CDK4/6 inhibitor, are the current standard-of-care first-line therapy for patients with advanced-stage hormone receptor-positive (HR) breast cancer. Resistance to anti-oestrogen agents inevitably occurs, mediated by oestrogen receptor (ER)-dependent or ER-independent mechanisms that drive tumour progression. Emerging endocrine therapies include, but are not limited to, next-generation oral ER degraders and proteolysis targeting chimeras, which might be particularly effective in patients with ESR1-mutant breast cancer.

Use of a Smartphone Application to Promote Adherence to Oral Medications in Patients With Breast Cancer.

Purpose: Medication nonadherence is common among patients with breast cancer (BC) and increases BC mortality and complications from comorbidities. There is growing interest in mobile health interventions such as smartphone applications (apps) to promote adherence.

Methods: Use of Medisafe, a medication reminder and tracking app, was tested over 12 weeks among patients on BC treatment and at least one oral medication.

Prospective investigation of amino acid transport and PSMA-targeted positron emission tomography for metastatic lobular breast carcinoma.

Purpose: To explore the feasibility of imaging amino-acid transport and PSMA molecular pathways in the detection of metastatic breast invasive lobular carcinoma (ILC) and if there is superior detection compared to standard-of-care imaging [computed tomography (CT)/bone scan, or F-FDG positron-emission-tomography (PET)-CT].

Methods: 20 women with de-novo or suspected metastatic ILC underwent two PET-CT scans with F-fluciclovine and Ga-PSMA-11 on separate days. Uptake per patient and in 3 regions per patient - ipsilateral axillary lymph node (LN), extra-axillary LN (ipsilateral supraclavicular or internal mammary), or distant sites of disease - was compared to standard-of-care imaging (CT/bone scan in 13 patients and F-FDG PET-CT in 7 patients).

FLT1 activation in cancer cells promotes PARP-inhibitor resistance in breast cancer.

Acquired resistance to PARP inhibitors (PARPi) remains a treatment challenge for BRCA1/2-mutant breast cancer that drastically shortens patient survival. Although several resistance mechanisms have been identified, none have been successfully targeted in the clinic. Using new PARPi-resistance models of Brca1- and Bard1-mutant breast cancer generated in-vivo, we identified FLT1 (VEGFR1) as a driver of resistance.

Real-world use patterns, effectiveness, and tolerability of sacituzumab govitecan for second-line and later-line treatment of metastatic triple-negative breast cancer in the United States.

Purpose: Patients with metastatic triple-negative breast cancer (mTNBC) have poor prognosis and limited treatment options. Sacituzumab govitecan (SG), a Trop-2-directed antibody-drug conjugate, is approved for patients with mTNBC who have received ≥ 2 systemic therapies (≥ 1 in the metastatic setting) based on the ASCENT study (NCT02574455). The current study describes real-world SG use and outcomes in patients with mTNBC in the United States.

Comprehensive genomic profiling of ESR1, PIK3CA, AKT1, and PTEN in HR(+)HER2(-) metastatic breast cancer: prevalence along treatment course and predictive value for endocrine therapy resistance in real-world practice.

Background: The treatment landscape for HR(+)HER2(-) metastatic breast cancer (MBC) is evolving for patients with ESR1 mutations (mut) and PI3K/AKT pathway genomic alterations (GA). We sought to inform clinical utility for comprehensive genomic profiling (CGP) using tissue (TBx) and liquid biopsies (LBx) in HR(+)HER2(-) MBC.

Methods: Records from a de-identified breast cancer clinicogenomic database for patients who underwent TBx/LBx testing at Foundation Medicine during routine clinical care at ~ 280 US cancer clinics between 01/2011 and 09/2023 were assessed.

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 a plasma-stable, cleavable linker to a potent topoisomerase I inhibitor payload, with activity observed in advanced TNBC.

Subgroup analyses from the phase 3 ASCENT study of sacituzumab govitecan in metastatic triple-negative breast cancer.

In this post hoc analysis of the ASCENT study, we compared outcomes with sacituzumab govitecan (SG) vs single-agent chemotherapy in clinically important subgroups of patients with metastatic triple-negative breast cancer (mTNBC). Patients with mTNBC refractory to/relapsing after ≥2 prior chemotherapies (≥1 in the metastatic setting) were randomized 1:1 to receive SG or treatment of physician's choice (TPC) until unacceptable toxicity/progression. The primary endpoint was progression-free survival (PFS) per RECIST 1.

Pharmacological suppression of the OTUD4/CD73 proteolytic axis revives antitumor immunity against immune-suppressive breast cancers.

Despite widespread utilization of immunotherapy, treating immune-cold tumors remains a challenge. Multiomic analyses and experimental validation identified the OTUD4/CD73 proteolytic axis as a promising target in treating immune-suppressive triple negative breast cancer (TNBC). Mechanistically, deubiquitylation of CD73 by OTUD4 counteracted its ubiquitylation by TRIM21, resulting in CD73 stabilization inhibiting tumor immune responses.