Clinical trial Recruiting at 109 sites Phase 3 Interventional Ages 18 and up

Obrixtamig plus standard chemotherapy in advanced epNEC

Official title: A Phase III, Multi-center, Open-label, Randomised, Controlled Trial of Intravenous Obrixtamig in Combination With Carboplatin and Etoposide vs. Carboplatin and Etoposide as First-line Therapy in DLL3-positive Patients With Unresectable Locally Advanced or Metastatic Extrapulmonary Neuroendocrine Carcinomas

Run by Boehringer Ingelheim · NCT07544654 · Data updated 2026-11-12

This trial tests whether adding obrixtamig to standard platinum-etoposide chemotherapy helps people with advanced extrapulmonary neuroendocrine cancer live longer than standard chemotherapy alone.

Quick facts

PhasePhase 3
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment390 (estimated)
SponsorBoehringer Ingelheim
Industry-sponsored
Drugs / interventionschemotherapy, radiation
Locations170 sites (Scottsdale, Arizona and 169 other locations)
StatusRecruiting
StartedJuly 10, 2026
Main results expectedDecember 13, 2029
Study endsDecember 13, 2029
Registry record updatedNovember 10, 2026
Trial IDNCT07544654 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults with poorly differentiated unresectable locally advanced or metastatic epNEC, Ki-67 >20% or high mitotic rate, and tumors meeting the specified histology criteria; no prior systemic treatment for unresectable/metastatic epNEC (with limited prior exposure allowed).

Probably not a fit

Patients whose tumors do not express the target or who do not respond to the addition of obrixtamig may not derive benefit and could experience treatment-related toxicities.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This phase 3 interventional study compares obrixtamig plus carboplatin and etoposide to standard carboplatin and etoposide in adults with unresectable locally advanced or metastatic extrapulmonary neuroendocrine cancer. Participants are randomized to receive either obrixtamig with standard chemotherapy followed by obrixtamig alone for up to three years, or standard chemotherapy alone for about four months. Treatments are given via infusion, with regular study visits; the treatment arm includes overnight stays. A companion DLL3 measurement device (Ventana DLL3 RxDx assay) is being evaluated alongside the therapeutic approach. The study aims to determine whether adding obrixtamig improves survival outcomes compared with standard therapy alone.

Why it matters

Potential benefit: If successful, patients may experience longer survival and potential disease control with obrixtamig in combination with chemotherapy.

How similar studies have gone: Previous approaches combining targeted antibodies with chemotherapy have shown promise in similar neuroendocrine contexts, but this exact combination and disease setting is relatively novel and requires results from this trial.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Patients with poorly differentiated unresectable locally advanced or metastatic extrapulmonary neuroendocrine carcinoma (epNEC) with Ki-67 \>20% or mitotic rate mitotic rate with number of mitoses \>20 per 2 mm2, regardless of primary site (including site of unknown origin)
2. Patients with tumours with mixed histologies are eligible only if neuroendocrine carcinoma component is predominant and represents more than 70% of the overall tumour tissue
3. No prior systemic treatment for unresectable locally advanced or metastatic epNEC (except for the completed one cycle of standard platinum + etoposide). Prior peri-operative chemotherapy or -radiation for curative intention is allowed if at least 6 months have elapsed between completion of this therapy and diagnosis of unresectable locally advanced or metastatic disease
4. Patients who have finished one cycle of standard platinum + etoposide regimen as first-line treatment (Cycle 0: etoposide with carboplatin or cisplatin, administered at a minimum dose of cisplatin 75 mg/m2 or carboplatin area under the curve (AUC) 5 and etoposide 80 mg/m2) prior to randomisation
5. Patients must comply with criteria for receiving further chemotherapy treatment as first-line standard of care (SoC) treatment within 28 days after the start of the initial chemotherapy (Cycle 0)
6. Adequate archival Formalin-Fixed Paraffin-Embedded (FFPE) tumour tissue, as specified in the Laboratory Manual, must be available for central laboratory analysis of Delta-like ligand 3 (DLL3) expression status. Tumours must be positive (as defined in the diagnostic study protocol) for DLL3 expression status assessed by investigational VENTANA DLL3 (SP347) RxDx Assay
7. Eastern Cooperative Oncology Group (ECOG) score of 0 or 1
8. Male or female participants ≥18 years old and at least at the legal age of consent in countries where it is greater than 18 years at the time of signature of the informed consent form (ICF) Further inclusion criteria apply.

Exclusion Criteria:

1. Presence of leptomeningeal disease and/or carcinomatous meningitis
2. Patients with diagnosis of Merkel cell carcinoma or medullary thyroid carcinoma
3. Patients with neuroendocrine prostate cancer
4. Patients with well-differentiated neuroendocrine tumours of any grade according to the world health organization (WHO) classification, 5th edition
5. Patients with a history of well differentiated Neuroendocrine tumour (NET) tumour that transformed into poorly differentiated Neuroendocrine carcinoma (NEC)
6. Previous treatment with obrixtamig or other DLL3-targeting therapies (e.g. T-cell engager (TcEs), cell therapies, antibody-drug conjugates, or radiopharmaceuticals)
7. Previous treatment with anti-PD-1 or programmed death ligand 1 (PD-L1) therapies during the one cycle of standard platinum + etoposide first-line chemotherapy (Cycle 0)
8. Toxicity from previous treatments that has not resolved to ≤ Common Terminology Criteria for Adverse Events (CTCAE) Grade 1 or grade prior to Cycle 0. Participants with alopecia any grade, CTCAE ≤Grade 2 asthenia/fatigue, amenorrhea/menstrual disorders any grade, CTCAE ≤Grade 2 peripheral neuropathy, and/or CTCAE ≤Grade 2 endocrinopathies controlled by replacement therapy, and toxicities, which are considered irreversible but stable for at least 4 weeks, per Investigator judgement may be eligible Further exclusion criteria apply.

Where it's running

  • City of Hope-Duarte-56419
    Duarte, California, United States
    Recruiting
  • Emory University
    Atlanta, Georgia, United States
    Recruiting
  • Washington University School of Medicine
    St Louis, Missouri, United States
    Recruiting
  • University of Tennessee
    Knoxville, Tennessee, United States
    Recruiting
  • SCRI Oncology Partners
    Nashville, Tennessee, United States
    Recruiting
  • Centro Medico Reumatologico - OMI
    Caba, Argentina
    Recruiting
Show 44 more locations
  • Hospital Britanico de Buenos Aires
    Caba, Argentina
    Recruiting
  • Clinica Privada Independencia
    Munro, Argentina
    Recruiting
  • Sanatorio Parque S.A.
    Rosario, Argentina
    Recruiting
  • Royal North Shore Hospital
    St Leonards, New South Wales, Australia
    Recruiting
  • Flinders Medical Centre
    Bedford Park, South Australia, Australia
    Recruiting
  • Peter MacCallum Cancer Centre
    Melbourne, Victoria, Australia
    Recruiting
  • Fiona Stanley Hospital
    Murdoch, Western Australia, Australia
    Recruiting
  • Cliniques Universitaires Saint-Luc
    Brussels, Belgium
    Recruiting
  • Universitair Ziekenhuis Antwerpen
    Edegem, Belgium
    Recruiting
  • UZ Leuven
    Leuven, Belgium
    Recruiting
  • Centre Hospitalier Universitaire de Liège
    Liège, Belgium
    Recruiting
  • Hospital de Amor
    Barretos, Brazil
    Recruiting
  • Instituto D'Or de Pesquisa E Ensino - Pe
    Recife, Brazil
    Recruiting
  • Fundacao Faculdade Regional de Medicina de Sao Jose do Rio Preto
    São José do Rio Preto, Brazil
    Recruiting
  • ICESP - Instituto do Cancer do Estado de Sao Paulo
    São Paulo, Brazil
    Recruiting
  • A.C. Camargo
    São Paulo, Brazil
    Recruiting
  • Sunnybrook Health Sciences Centre
    Toronto, Ontario, Canada
    Recruiting
  • Instituto Oncologico FALP
    Providencia, Chile
    Recruiting
  • Bradford Hill- Centro de Investigacion Clinica
    Recoleta, Chile
    Recruiting
  • Clinica Alemana de Santiago S.A.
    Santiago, Chile
    Recruiting
  • Beijing Cancer Hospital
    Beijing, China
    Recruiting
  • Beijing GoBroad Hospital
    Beijing, China
    Recruiting
  • Xiangya Hospital, Central South University
    Changsha, China
    Recruiting
  • Sichuan Cancer Hospital
    Chengdu, China
    Recruiting
  • West China Hospital, Sichuan University
    Chengdu, China
    Recruiting
  • Chongqing University Affiliated Cancer Hospital
    Chongqing, China
    Recruiting
  • Fujian Cancer Hospital
    Fuzhou, China
    Recruiting
  • The First Affiliated Hospital,Sun Yat-sen University
    Guangzhou, China
    Recruiting
  • Sir Run Run Shaw Hospital, Zhejiang University, School of Medicine
    Hangzhou, China
    Recruiting
  • Harbin Medical University Cancer Hospital
    Harbin, China
    Recruiting
  • Qilu Hospital, Shangdong University
    Jinan, China
    Recruiting
  • Shandong Cancer Hospital
    Jinan, China
    Recruiting
  • Linyi Cancer Hospital
    Linyi, China
    Recruiting
  • The First Affiliated Hospital of Henan University of Science and Technology
    Luoyang, China
    Recruiting
  • The Affiliated Cancer Hospital, Guangxi Medical University
    Nanning, China
    Recruiting
  • Shanghai General Hospital
    Shanghai, China
    Recruiting
  • Hubei Cancer Hospital
    Wuhan, China
    Recruiting
  • Masaryk Memorial Cancer Institute
    Brno, Czechia
    Recruiting
  • Aarhus University Hospital
    Aarhus N, Denmark
    Recruiting
  • Helsinki University Hospital
    Helsinki, Finland
    Recruiting
  • KYS Sädesairaala
    Kuopio, Finland
    Recruiting
  • Tampere University Hospital
    Tampere, Finland
    Recruiting
  • Turku University Hospital / TYKS
    Turku, Finland
    Recruiting
  • Hopital Beaujon
    Clichy, France
    Recruiting

+120 more sites. See ClinicalTrials.gov for the full list.

Study contacts

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.