Tests patritumab deruxtecan with other drugs in HER2 positive breast cancer
Tests patritumab deruxtecan with other drugs in adults with advanced HER2 positive breast cancer.
Key facts
- Who runs it
- Merck Sharp & Dohme LLC
- Where
- Haifa, Petah Tikva, and Ramat Gan, IsraelSee the 3 sitesAlso in 5 other countries, 15 sites
- Trial code
- NCT06686394
- EudraCT 2026-528266-19
- JRCT2041250022
- U1111-1346-4321
- Registry title
- Study of Patritumab Deruxtecan With Other Anticancer Agents in Participants With HER2 Positive Breast Cancer That Has Spread and Cannot Be Surgically Removed (MK-1022-009)
- Status
- Recruiting
- Phase
- Phase 1/2
- People taking part
- 181 people, planned
- Started
- 26 Feb 2025
- Expected to end
- 2 Aug 2032
- Type of study
- Interventional, 4 groups
- Treatments tested
- Patritumab deruxtecan
- Trastuzumab
- Trastuzumab Biosimilar
- Pertuzumab
- Tucatinib
- Record updated
- 21 October 2026
Who can take part
AI summary
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults with HER2 positive breast cancer that has spread or cannot be removed by surgery. It tests patritumab deruxtecan with other anticancer drugs.
- Age
- 18 years or older
- Sex
- All sexes can join
- Disease stage
- HER2 positive breast cancer, confirmed by tissue examination, that is locally advanced and cannot be removed by surgery, or that has spread (metastatic). ECOG performance status 0 to 1.
- Earlier treatment
- Part 1 Arm 1: 2 to 5 earlier lines of anti-HER2 treatment and disease progression on or after trastuzumab deruxtecan (T-DXd). Part 1 Arm 2: no more than 5 earlier lines of anti-HER2 treatment. Part 1 Arm 3: progression on T-DXd, which must be the most recent treatment, and no more than 3 earlier lines of anti-HER2 treatment. Part 2: no earlier systemic treatment, including T-DXd, for recurrent locally advanced or metastatic breast cancer.
- Biomarker or test result
- HER2 positive breast cancer. People with HIV can join if HIV is well controlled on antiretroviral therapy. People with hepatitis B or C can join if the viral load is undetectable.
Main reasons for not taking part
- Uncontrolled or significant heart disease
- History of interstitial lung disease or pneumonitis, or current or suspected interstitial lung disease
- Evidence of spinal cord compression or brain metastases
- Active infection that needs treatment with medicines for the whole body
- Part 1 Arm 3 only: earlier tucatinib, lapatinib, neratinib or an investigational HER2-targeted tyrosine kinase inhibitor
The registry criteria, word for word
Show all 23 criteriaShow less
Who can take part
- The main inclusion criteria include but are not limited to the following:
- Has histologically confirmed HER2+ locally advanced unresectable breast cancer or metastatic breast cancer
- Human immunodeficiency virus (HIV)-infected participants must have well-controlled HIV on antiretroviral therapy (ART)
- Participants who are hepatitis B surface antigen (HBsAg) positive are eligible if they have received HBV antiviral therapy for at least 4 weeks, and have undetectable hepatitis B virus (HBV) viral load before allocation
- Participants with history of hepatitis C virus (HCV) infection are eligible if HCV viral load is undetectable
- Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1 within 7 days before start of study intervention; Part 1 Arm 1:
- Has received at least a minimum of 2 and a maximum of 5 prior lines of anti-HER2 therapy in the locally advanced or metastatic setting
- Had disease progression on or after any previous trastuzumab deruxtecan (T-DXd) treatment; Part 1 Arm 2:; -Has received no more than 5 prior lines of anti-HER2 therapy in the locally advanced or metastatic setting; Part 1 Arm 3:; -Has received and had disease progression from T-DXd treatment in any setting and a maximum of 3 prior lines of anti-HER2 therapy in the locally advanced or metastatic setting. T-DXd must be the most recent therapy received before enrollment; Part 2 : Has not received prior systemic therapy (including T-DXd) for recurrent locally advanced or metastatic breast cancer (mBC)
Who cannot take part
- Concurrent active HBV and HCV infection
- Has had major surgical procedure (excluding placement of vascular access) less than 28 days; Part1: Arm 3 ONLY
- Has received prior treatment with tucatinib, lapatinib, or neratinib, or any investigational HER2-targeted tyrosine kinase inhibitors in the locally advanced or metastatic setting
- Uncontrolled or significant cardiovascular disease
- Has any history of (noninfectious) interstitial lung disease (ILD)/ pneumonitis irrespective of steroid use or has current ILD or suspected ILD
- Has any history of or evidence of any current leptomeningeal disease
- Has clinically significant corneal disease
- Evidence of ongoing uncontrolled systemic bacterial, fungal, or viral infection
- HIV infected participants with a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease
- Known additional malignancy that is progressing or has required active treatment within the past 3 years
- Has an active infection requiring systemic therapy
- The main exclusion criteria include but are not limited to the following:
- Has clinically severe respiratory compromise
- Part 1: Evidence of spinal cord compression or brain metastases
- Part 2: Evidence of spinal cord compression or brain/CNS metastases
Where in Israel
Also in 5 other countries, 15 sites
- Rambam Health Care Campus (Site 0011)Haifa, IsraelContact: Study CoordinatorTaking people
- Rabin Medical Center (Site 0012)Petah Tikva, IsraelContact: Study CoordinatorTaking people
- Sheba Medical Center (Site 0010)Ramat Gan, IsraelContact: Study CoordinatorTaking people
About the trial
What the trial wants to find out
Researchers want to learn if patritumab deruxtecan (MK-1022) can treat certain breast cancers. The breast cancers being studied are HER2 positive unresectable locally advanced or metastatic (the cancer has spread to other parts of the body). The goals of this study are to learn:
Read full original descriptionShow less
* About the safety and how well people tolerate of patritumab deruxtecan * How many people have the cancer respond (get smaller or go away) to treatment
The 4 groups in the trial
- Part 1: Patritumab deruxtecan plus trastuzumabTreatment being tested
Participants receive patritumab deruxtecan intravenous (IV) infusion and trastuzumab or trastuzumab biosimilar IV infusion on Day 1 of each 21-day cycle (every 3 weeks) until disease progression, intolerable toxicity, or investigator decision.
Treatment: Patritumab deruxtecan, Trastuzumab, and Trastuzumab Biosimilar
- Part 1: Patritumab deruxtecan plus pertuzumab and trastuzumabTreatment being tested
Participants receive patritumab deruxtecan IV infusion, pertuzumab IV infusion, and trastuzumab or trastuzumab biosimilar IV infusion on Day 1 of each 21-day cycle (every 3 weeks) until disease progression, intolerable toxicity, or investigator decision.
Treatment: Patritumab deruxtecan, Trastuzumab, Trastuzumab Biosimilar, and Pertuzumab
- Part 1: Patritumab deruxtecan plus trastuzumab and tucatinibTreatment being tested
Participants receive patritumab deruxtecan IV infusion and trastuzumab or trastuzumab biosimilar IV infusion on Day 1 of each 21-day cycle (every 3 weeks), and tucatinib is administered orally twice daily for each 21-day cycle, until disease progression, intolerable toxicity, or investigator decision.
Treatment: Patritumab deruxtecan, Trastuzumab, Trastuzumab Biosimilar, and Tucatinib
- Part 2: Patritumab deruxtecan plus pertuzumab and trastuzumabTreatment being tested
Participants receive patritumab deruxtecan IV infusion, pertuzumab IV infusion, and trastuzumab or trastuzumab biosimilar IV infusion on Day 1 of each 21-day cycle (every 3 weeks) until disease progression, intolerable toxicity, or investigator decision.
Treatment: Patritumab deruxtecan, Trastuzumab, Trastuzumab Biosimilar, and Pertuzumab
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorData and sources
- Registry record
- Listed on ClinicalTrials.gov.
- Official title
- HERTHENA-Breast-01: A Phase 1b/2, Multicenter, Open-label, Dose-Finding Study to Evaluate the Safety and Antitumor Activity of Patritumab Deruxtecan in Participants With HER2 Positive Unresectable Locally Advanced Breast Cancer or Metastatic Breast Cancer
- Plain-language title
- Tests patritumab deruxtecan with other drugs in HER2 positive breast cancerGenerated from the registry record. The registry title is the official one.
- AI summary
- From the trial's eligibility criteria. Read by machine on 12 November 2026.
- Record updated
- 21 October 2026