T-DXd Based Therapy Followed by Endocrine Therapy Plus Dual HER2 Blockade in First-line HER2+/ HR… (NCT07683754) | Clinical Trial Compass
Not Yet RecruitingPhase 3
T-DXd Based Therapy Followed by Endocrine Therapy Plus Dual HER2 Blockade in First-line HER2+/ HR+ Metastatic Breast Cancer and Retreatment With T-DXd
200 participantsStarted 2026-09-04
Plain-language summary
This study will evaluate a structured sequential treatment strategy starting with T-DXd + pertuzumab upfront therapy, followed by an optimized maintenance therapy with dual HER2+blockade + CDK4/6i + ET and the opportunity to retreat with T-DXd once patients progress under maintenance aimed to maximizing disease control, optimizing tolerability, and preserving T-DXd as a future therapeutic option, while ensuring participant safety and regulatory compliance in participants with HER2+/HR+ advanced/metastatic breast cancer.
Who can participate
Age range
18 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Sign and date the Main Trial informed consent form (ICF), prior to the start of any trial-specific procedures.
. Participant must be ≥18 years of age at the time the ICF is signed.
. Have pathologically documented breast cancer that:
. Has not received prior chemotherapy or HER2-targeted therapy for mBC. Participant who has received chemotherapy or HER2-targeted therapy or radiotherapy or surgery in the neoadjuvant or adjuvant setting are eligible, with a DFI of \>6 months (\>183 days) from completion of systemic chemotherapy or any HER2-targeted therapy (antibody, TKI or T-DM1) to diagnosis of advanced or metastatic disease.
. ECOG PS of 0 or 1 assessed no more than 3 days prior to initiation of trial intervention.
. Has at least 1 lesion, not previously irradiated, that can be measured accurately at baseline as ≥10 mm in the longest diameter (except lymph nodes, which must have short axis ≥15 mm) with CT or MRI, which is suitable for accurate repeated measurements, or nonmeasurable, bone-only disease that can be assessed by CT, MRI, or X-ray.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Progression-free Survival (PFS) Rate at 24 Months
Timeframe: From start of Upfront Treatment phase until disease progression (PD) or death, whichever occurs first, up to approximately 24 months
. Participant with brain metastases are allowed if participant is asymptomatic and does not require immediate local intervention.
. Has received at least 1 dose of Maintenance Treatment.
Exclusion criteria
. Has prior therapy with any CDK inhibitor.
. Previous T-DXd therapy for early BC with an EFS or disease-free interval of \< 12 months from completion of T-DXd therapy in the neoadjuvant or post-neoadjuvant setting.
. Is receiving concurrent therapy with other trial interventions (except pertuzumab which is part of Upfront Treatment and Maintenance Treatment).
. Has prior therapy with any CDK inhibitor.
. Has any unresolved SAE related to prior T-DXd + pertuzumab treatment from the Upfront Treatment Phase, defined as an event that has not resolved to baseline by the time of the eligibility assessment for the Maintenance Treatment Phase.
. Has experienced Grade 3 or 4 ILD/pneumonitis during the Upfront Treatment Phase.
. Has spinal cord compression or clinically active CNS metastases, defined as untreated or symptomatic, or requiring therapy with corticosteroids or anticonvulsants to control associated symptoms.
. Participant who developed ILD/pneumonitis Grade ≥2 during the Upfront Treatment Phase or Maintenance Treatment Phase.