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NCT03321981 · ClinicalTrials.gov registry record · Phase 2

MCLA-128 With Trastuzumab/Chemotherapy in HER2+ and With Endocrine Therapy in ER+ and Low HER2 Breast Cancer.

A Phase 2 study of Breast Cancer Metastatic, sponsored by Merus B.V..

Completed
Registry status
Phase 2
Development phase
105
Enrollment target
20
Study locations

NCT03321981: Completed Phase 2 study of Breast Cancer Metastatic, sponsored by Merus B.V..

NCT03321981 is a Phase 2 study of Breast Cancer Metastatic that has completed, run by Merus B.V.. The registered enrollment target is 105 participants, above the 86-participant average among 17 other Breast Cancer Metastatic trials with a reported enrollment target (22% higher). The trial reports 20 study locations across 5 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03321981, a Phase 2 study of Breast Cancer Metastatic, has completed, sponsored by Merus B.V..

COMPLETED
Registry status
Phase 2
Development phase
105 participants
Enrollment target
20
Study locations

Study Summary

A Phase 2, open-label, multicenter international study will be performed to evaluate the efficacy of MCLA-128-based combinations. Three combination treatments will be evaluated, two in Cohort 1 and one in Cohort 2. MCLA-128 (zenocutuzumab) is given in combinations in two metastatic breast cancer (MBC) populations, Human Epidermal Growth Factor Receptor (HER) 2-positive/amplified (Cohort 1) and Estrogen Receptor-positive/low HER2 expression (Cohort2). Two combinations treatments will be evaluated in Cohort 1, the doublet and triplet. Initially zenocutuzumab is given in combination with trastuzumab in the doublet. After the safety of the doublet has been assessed in 4-6 patients, MCLA-128 is given in combination with trastuzumab and vinorelbine in the triplet, in parallel to the efficacy expansion of the doublet. The doublet and triplet combinations are both evaluated in two steps with an initial safety run-in followed by a cohort efficacy expansion. In total up to 40 patients evaluable for efficacy are included in both the doublet and triplet. In Cohort 2 zenocutuzumab is administered in combination with the same previous endocrine therapy on which progressive disease is radiologically documented. A total of up to 40 patients evaluable for efficacy are included in the Cohort 2.

Primary Outcome

Clinical benefit rate (CBR) at 24 weeks per investigator assessment. CBR is the proportion of patients with confirmed Complete Response (CR) or Partial Response (PR), or Stable Disease (SD) lasting 24 weeks.

Conditions Studied

Interventions

  • DRUG Trastuzumab
  • DRUG Endocrine therapy
  • DRUG Vinorelbine
  • DRUG Zenocutuzumab

Study Locations (20)

Other

  • Institut Jules Bordet - Brussels
  • Grand Hôpital de Charleroi (GHdC) - Charleroi
  • UZ Leuven - Leuven
  • Hôpital Jean Minjoz - Besançon
  • Centre Jean Perrin - Clermont-Ferrand
  • Centre Georges-Francois Leclerc - Dijon
  • Centre Léon Bérard - Lyon
  • Institut Paoli Calmette - Marseille
  • Centre René Huguenin - Saint-Cloud
  • Centre Paul Strauss - Strasbourg
  • Centre Claudius Régaud - Toulouse
  • Institute Gustave Roussy - Villejuif
  • Champalimaud Clinical Centre - Lisbon
  • Hopistal San Antonio - Porto
  • Instituto Português Oncologia - Porto
  • Vall D'Hebron Institute of Oncology (VHIO) - Barcelona

California

  • Cedars-Sinai Medical Center - Los Angeles

Kansas

  • HCA Midwest Health - Kansas City

Tennessee

  • Sarah Cannon Research Institute - Nashville

North Holland

  • Netherlands Cancer Institute NKI - Amsterdam

Trial Details

FieldValue
Enrollment Target 105 participants
Start Date 2018-01-15
Est. Completion 2023-07-26
Phase Phase 2
Merus B.V.

8 total trials

What the finished NCT03321981 record still lists

NCT03321981 is an interventional study that assigns participants to a tested intervention. The registered 105 participants enrollment target is mid-sized for trials with a published cap, above the 86-participant average among 17 other Breast Cancer Metastatic trials with a reported enrollment target (22% higher).

The record links to 1 condition, with Breast Cancer Metastatic appearing as the primary indexed condition, and to 4 interventions - of which Trastuzumab is the first listed.

NCT03321981 names 20 study sites across 5 states, led by Other, California, Kansas.

Frequently Asked Questions

What is clinical trial NCT03321981 about?

NCT03321981 is a clinical study titled "MCLA-128 With Trastuzumab/Chemotherapy in HER2+ and With Endocrine Therapy in ER+ and Low HER2 Breast Cancer.". A Phase 2, open-label, multicenter international study will be performed to evaluate the efficacy of MCLA-128-based combinations. Three combination treatments will be evaluated, two in Cohort 1 and one in Cohort 2. MCLA-128 (zenocutuzumab) is given in combinations in two metastatic breast cancer (M...

What is the current status of trial NCT03321981?

This trial is currently completed. It is a Phase 2 study. The enrollment target is 105 participants. The study started on 2018-01-15. Estimated completion is 2023-07-26.

What conditions does trial NCT03321981 study?

This clinical trial studies the following conditions: Breast Cancer Metastatic.

What interventions are being tested in trial NCT03321981?

The interventions under investigation include: Trastuzumab (DRUG), Endocrine therapy (DRUG), Vinorelbine (DRUG), Zenocutuzumab (DRUG).

Who is sponsoring clinical trial NCT03321981?

This trial is sponsored by Merus B.V., which has 8 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT03321981 being conducted?

This trial has 20 study locations across California, Kansas, Tennessee, North Holland. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Breast Cancer Metastatic

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT03321981's enrollment target sits among peer trials

105 5th of 17 higher than 13 of 17 other Breast Cancer Metastatic trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Breast Cancer Metastatic trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03321981, the US trial registry maintained by the National Library of Medicine. NCT03321981 (mid enrollment · wide site footprint · completed) retrieved and formatted by PlainTrial, see methodology.