HER2-positive Breast Cancer

Thie purpose of this study is to find out whether a personalized treatment approach-using a series of ctDNA tests along with standard imaging scans to help decide when to step up (escalate) or decrease (de-escalate) sequential treatments (given one after another)-combined with local therapies (which treat cancer in a specific part of the body) and treatments that prevent cancer from spreading to the central nervous system (CNS; including the brain and spinal cord) can result in long-lasting remission and possibly cure some participants with HER2+ metastatic breast cancer.

Adult men and women with early-stage, IHC/FISH-defined HER2-positive breast cancer will have a MammaPrint®/BluePrint® assay performed on the diagnostic biopsy specimen, ordered by the treating Oncologist as standard care

This research study is studying how well newly diagnosed breast cancer that has tested positive for a protein called HER2 responds using one of two different combination of HER2-directed therapies as a treatment after surgery. The name of the study drugs involved are: * Trastuzumab-emtansine (T-DM1, Kadcyla) * Trastuzumab SC (Herceptin Hylecta) * Paclitaxel

The purpose of the study is to see if using an investigational drug called \[18F\]FMISO with PET/MRI imaging can help monitor and predict the effect of trastuzumab (Herceptin) on chemotherapy in patients diagnosed with advanced HER2 positive breast cancer. This study is for imaging purposes only and is not a treatment study. The results of this study will not change a patient's clinical treatment plan but it may help physicians and researchers better understand how best to treat patients with breast cancer in the future.

The purpose of this protocol is to give continued access to tucatinib eligible participants. It also enables ongoing safety follow-up for those who continue to benefit from the study treatment. These participants were part of Pfizer-sponsored tucatinib parent studies that will be closed. Additional follow-up safety information will be collected. This will allow further understanding of the safety profile of tucatinib in participants who continue to receive the study treatment.

The Phase 2 monotherapy portion of this study is currently enrolling and will evaluate the efficacy and safety of PC14586 (INN rezatapopt) in participants with locally advanced or metastatic solid tumors harboring a TP53 Y220C mutation. The Phase 1 portion of the study will assess the safety, tolerability and preliminary efficacy of multiple dose levels of rezatapopt as monotherapy and in Phase 1b in combination with pembrolizumab.

The purpose of this study is to test the safety and effectiveness of a sequence of drugs (a Taxane plus Trastuzumab plus Pertuzumab followed by Trastuzumab Deruxtecan, followed by Tucatinib plus Ado-Trastuzumab Emtansine (T-DM1), followed by Trastuzumab plus Pertuzumab plus Tucatinib) in HER2+ Breast Cancer. The study will help investigators understand whether first intensifying therapy for a specific period and then stopping treatment is safe and effective for participants. The names of the study drugs involved in this study are: * Paclitaxel (a type of anti-microtubule agent) * Docetaxel (a type of anti-microtubule agent) * Nab-Paclitaxel (a type of anti-microtubule agent) * Trastuzumab (a type of IgG1 kappa monoclonal antibody) * Pertuzumab (a type of monoclonal antibody) * Trastuzumab Deruxtecan (a type of HER2-directed antibody drug conjugate) * Tucatinib (Tyrosine Kinase HER2 Inhibitor) * Ado-trastuzumab emtansine or T-DM1 (a type of HER2-targeted antibody-drug conjugate)

High pathological complete response (pCR) rates are seen using different neoadjuvant chemotherapy schedules with trastuzumab and pertuzumab in HER2-positive stage II-III breast cancer patients. Total pCR rates in breast and axilla have been described as high as 64%, and with an even higher rate of \>80% in patients with HER2-positive and hormone receptor (HR) negative tumors. pCR is associated with better long-term outcomes in patients with HER2-positive breast cancer. Neoadjuvant treatment of HER2-positive breast cancer typically consists of six cycles of treatment. Longer duration of treatment is associated with higher pCR-rates but also with increased toxicity. It is therefore important to investigate which patients can safely be treated with less than six cycles of chemotherapy and which patients require six cycles for maximum efficacy.It is hypothesized that patients with a complete pathologic response may not benefit from additional chemotherapy, while those with residual invasive disease require further treatment. This study will evaluate de-escalation of the number of neoadjuvant chemotherapy cycles in intermediate risk HER2-positive breast cancer.

The purpose of this study is to assess the efficacy and safety of RO7771950 in combination with trastuzumab and capecitabine, compared to tucatinib in combination with trastuzumab and capecitabine.

The goal of this clinical trial is to learn if single-agent SMP-656 works to treat patients with HER2-positive locally advanced or metastatic breast cancer who have progressed after prior HER2-targeted topoisomerase inhibitor antibody-drug conjugate (ADC) treatment. It will also evaluate the safety of SMP-656 and identify the optimal dose for future trials. The main questions it aims to answer are: What is the objective tumor response rate (DOR, PFS, DCR, OS) of two different dose regimens of intravenous SMP-656? What are the side effects and safety risks of these two SMP-656 dose regimens? Which dose level achieves the best balance of anti-cancer activity and tolerability? This is a randomized, open-label, dose-optimization Phase II clinical trial. Participants will be randomly assigned 1:1 to receive one of two fixed doses of SMP-656 given intravenously once every 3 weeks. Participants will: Complete screening tests within 28 days before the first SMP-656 infusion to confirm eligibility Receive study treatment every 3 weeks until cancer progression, intolerable side effects, withdrawal, or other stopping criteria Have regular tumor imaging scans, physical exams, vital sign checks, and blood tests to monitor tumor response and safety Attend a safety follow-up visit 30 days after the last dose of SMP-656 Complete longer-term survival follow-up after the 30-day safety check Provide optional blood and tumor tissue samples for additional research studies

This phase II, multicenter, open-label, randomized controlled trial (FACET study) evaluates the efficacy and safety of fulvestaciclib, a novel oral CDK4/6 inhibitor, combined with anti-HER2 dual blockade (trastuzumab and pertuzumab, HP) and endocrine therapy (ET) in hormone receptor-positive (HR+) and HER2-positive advanced breast cancer (ABC). Patients with HR+/HER2+ ABC without prior systemic therapy for advanced disease are randomized in a 1:1:1 ratio into three arms, stratified by visceral metastasis status (yes vs. no) and metastatic type (de novo vs. recurrent). Arm A: After 4-8 cycles of induction chemotherapy (taxane) plus HP, patients receive fulvestaciclib + HP + ET as maintenance therapy. Arm B: After 4-8 cycles of induction chemotherapy (taxane) plus HP, patients receive HP + ET alone (without fulvestaciclib) as maintenance therapy. Arm C (exploratory): Patients receive upfront fulvestaciclib + HP + ET as first-line therapy without induction chemotherapy (chemo-free). For premenopausal/perimenopausal patients, ovarian function suppression (OFS) is added in all arms. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or death. The primary endpoint is investigator-assessed progression-free survival (PFS) comparing Arm A versus Arm B. Secondary endpoints include PFS (Arm A vs. Arm C), overall survival (OS), objective response rate (ORR), clinical benefit rate (CBR), duration of response (DoR), cumulative incidence of central nervous system (CNS) metastases, safety, and patient-reported outcomes (PROs).

Heroes is a multicentre, national, non-randomized, open-label, phase 2 study. The goal of this clinical trial is to evaluate the feasibility of therapeutic de-escalation in HER2-positive metastatic breast cancer with disease controlled after 2 years of maintenance treatment with anti-HER2 targeted therapy AND ctDNA negative testing. The main question it aims to answer is : • Is it possible to identify patients for whom temporary or permanent discontinuation of treatment is possible without impacting prognosis?

The purpose of this study is to see if zanidatamab is safe and effective, when combined with chemotherapy, in treating people who has Human Epidermal Growth Factor Receptor 2 (HER2)-positive, early-stage breast cancer

This is an open-label, single-center, exploratory, Phase Ib/II clinical trial evaluating the safety and efficacy of entinostat combined with pyrotinib and endocrine therapy in patients with advanced hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-positive (HER2+) breast cancer who have failed prior trastuzumab-based therapy. The study consists of two parts: Part I (Phase Ib) employs a 3+3 dose-escalation design to determine the dose-limiting toxicity (DLT), maximum tolerated dose (MTD), and recommended Phase II dose (RP2D) of entinostat when given in combination with pyrotinib (400 mg daily) and endocrine therapy. Part II (Phase II) uses a Simon two-stage design to further evaluate the efficacy and safety of the combination at the RP2D. The primary efficacy endpoint is progression-free survival (PFS) based on RECIST v1.1. A total of approximately 79-94 participants will be enrolled.

This study is designed to compare efficacy and safety of GQ1005 versus T-DM1 in HER2-positive, unresectable and/or metastatic breast cancer patients previously treated with trastuzumab and taxane.

This study will evaluate the efficacy and non-inferiority of a non-surgical approach for the treatment of patients with locally advanced breast cancer.

The purpose of this study is to determine whether AGuIX (Activation and Guidance of Irradiation by X-ray) gadolinium-based nanoparticles make radiation work more effectively in the treatment of patients with brain metastases that are more difficult to control with stereotactic radiation alone.

This study aims to evaluate the efficacy and safety of probiotics for the prevention of diarrhea in patients with breast cancer receiving the tyrosine kinase inhibitor (TKI) Neratinib. Study Design: This is a prospective, randomized controlled clinical trial. Participants will be randomly assigned to either a probiotics intervention group or a placebo-controlled group. Both groups will receive prophylactic loperamide according to the FDA-recommended dosing schedule for neratinib-associated diarrhea. Primary Objective: To evaluate the efficacy of probiotics in reducing the incidence and severity of diarrhea in patients receiving Neratinib. Secondary Objectives: This study will also investigate the effects of probiotics on gut microbiota composition and their potential impact on drug efficacy. Study Duration: Enrollment is planned from August 2025 to June 2027 at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University. Both the intervention and control groups will receive treatment for a total of six weeks (two cycles of three weeks each). No post-treatment observation period is included. Eligibility Criteria: Participants must be diagnosed with HER2-positive breast cancer and scheduled to receive Neratinib. Exclusion criteria include patients with severe gastrointestinal disorders or recent probiotic consumption.

This study is a response-adapted, multicenter, interventional trial enrolling patients with HER2-positive early or locally advanced breast cancer. All enrolled patients will first receive 2 cycles of standard neoadjuvant THP regimen, consisting of a taxane, trastuzumab, and pertuzumab. After the initial 2-cycle treatment, tumor response will be evaluated by radiologic imaging and patient-derived organoid (PDO) drug sensitivity testing. Patients with an inadequate response to THP are defined as those with \<50% tumor size reduction on imaging, or failure to reach the PDO sensitivity threshold (\<80% tumor cell killing for HER2+/HR- tumors; \<60% for HER2+/HR+ tumors). These non-responders will switch to receive 4 cycles of trastuzumab rezetecan (SHR-A1811), a novel HER2-targeted antibody-drug conjugate (ADC). Patients with a favorable response (≥50% tumor reduction or meeting the PDO threshold) will continue with an additional 4 cycles of THP. The primary objective is to evaluate the pathologic complete response (pCR) rate in THP non-responders after switching to trastuzumab rezetecan. Secondary objectives include objective response rate (ORR), event-free survival (EFS), overall survival (OS), 3-year invasive disease-free survival (iDFS), and safety profiles of both treatment strategies. Outcomes in patients who continue THP will be described for exploratory purposes. A total of 124 patients will be enrolled. This response-adapted, individualized strategy aims to provide an effective option for HER2-positive breast cancer patients with an inadequate early response to conventional THP neoadjuvant therapy.

This is a single-arm, multicenter clinical study designed to evaluate the efficacy and safety of pyrotinib and trastuzumab combined with pegylated liposomal doxorubicin hydrochloride and cyclophosphamide followed by paclitaxel for injection albumin bound as neoadjuvant therapy in patients with early HER2-positive breast cancer. Eligible patients will receive 8 cycles of neoadjuvant treatment. Pyrotinib will be administered orally once daily, and trastuzumab will be administered intravenously every 3 weeks. During the first 4 cycles, patients will receive pegylated liposomal doxorubicin hydrochloride and cyclophosphamide. During the subsequent 4 cycles, patients will receive paclitaxel for injection albumin bound. The primary outcome is total pathological complete response rate. Secondary outcomes include breast pathological complete response rate, lymph node pathological complete response rate, objective response rate, event-free survival, distant disease-free survival, overall survival, and safety.

This trial is a registrational Phase III, randomized, open-label, multicenter study to evaluate the efficacy and safety of BL-M07D1 combined with Pertuzumab versus docetaxel plus Trastuzumab and Pertuzumab in patients with first-line HER2-positive recurrent or metastatic breast cancer.

This is a multicenter, non-randomized, prospective cohort study. The purpose of the study is to identify constitutional genetic factors associated with histological response, resistance or sensibility to treatment in human epidermal growth factor receptor 2 (HER2)-positive breast cancer. 9000 patients will be enrolled in this study. Blood samples will be collected after informed consent and inclusion in the study. Patients will be treated and followed according to the standards of their treating center. They will be followed every six months for five years.

This study aimed to evaluate the feasibility and safety, and to observe early efficacy signals of the focused ultrasound mediated drug delivery system combined with SonoVue® in patients with HER2-positive breast cancer receiving neoadjuvant therapy by comparing its pathological complete response (pCR) rate with a matched historical cohort of HER2-positive breast cancer patients treated at our center.

This is a Phase 1/1b open-label, multi-center dose escalation and dose optimization study designed to evaluate the safety and preliminary efficacy of IAM1363 in participants with advanced cancers that harbor HER2 alterations.

The purpose of this study is to establish a prospective, single-center platform research based on clinical subtypes to explore precision neoadjuvant therapy in patients with operable breast cancer who met the indications for neoadjuvant chemotherapy and by the update of basic translational research in the center, especially the refinement of typing, the discovery of new targets and the development of novel targeted drugs, verified the effectiveness of new targeted drugs in neoadjuvant therapy.