NCT06796907

Brief Summary

Advanced solid tumors are cancers that have spread to other parts of the body. While many treatments exist, most people become resistant to them, and the cancer returns. Researchers are developing new treatments that combine different medicines for those who do not respond to single medicine. This study is looking at how safe and tolerable GSK5733584 is, how the body handles it, and how well it works when used with other cancer medicines. The study will include participants with advanced solid tumors who have either not responded to standard treatments or cannot tolerate them or have no available effective treatment.

Trial Health

88
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
392

participants targeted

Target at P75+ for phase_1

Timeline
24mo left

Started Mar 2025

Typical duration for phase_1

Geographic Reach
20 countries

56 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress38%
Mar 2025Apr 2028

First Submitted

Initial submission to the registry

January 22, 2025

Completed
6 days until next milestone

First Posted

Study publicly available on registry

January 28, 2025

Completed
1 month until next milestone

Study Start

First participant enrolled

March 4, 2025

Completed
2.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 17, 2027

Expected
4 months until next milestone

Study Completion

Last participant's last visit for all outcomes

April 5, 2028

Last Updated

October 14, 2025

Status Verified

October 1, 2025

Enrollment Period

2.8 years

First QC Date

January 22, 2025

Last Update Submit

October 9, 2025

Conditions

Keywords

Solid TumorsGSK5733584BEHOLD-2

Outcome Measures

Primary Outcomes (4)

  • Part A: Percentage of participants with dose limiting toxicities (DLTs)

    Approximately 7 months

  • Part A: Number of participants with adverse events (AEs), immune-mediated adverse events (imAEs), adverse events of special interest (AESI), serious adverse events (SAEs) by Severity

    Up to approximately 22 months

  • Part A: Number of participants with adverse events (AEs), immune-mediated adverse events (imAEs), adverse events of special interest (AESI), serious adverse events (SAEs) by Frequency

    Up to approximately 22 months

  • Part B: Confirmed Objective Response Rate (ORR)

    ORR is defined as the percentage of participants with a best overall confirmed (BOR) of Partial Response (PR) or better per Response Evaluation Criteria in Solid Tumors (RECIST 1.1)

    Up to approximately 37 months

Secondary Outcomes (15)

  • Part A: Confirmed Objective Response Rate (ORR)

    Up to approximately 22 months

  • Parts A and B: Duration of response (DoR)

    Up to approximately 37 months

  • Parts A and B: Progression-free survival (PFS)

    Up to approximately 37 months

  • Part B: Overall Survival (OS)

    Up to approximately 37 months

  • Parts A and B: Maximum observed concentration (Cmax) of GSK5733584

    Up to approximately 37 months

  • +10 more secondary outcomes

Study Arms (4)

Module 1 (GSK5733584 +/- Dostarlimab) Endometrial Cancer

EXPERIMENTAL
Drug: GSK5733584Drug: Dostarlimab

Module 2 (GSK5733584 +/- Bevacizumab) Ovarian Cancer

EXPERIMENTAL
Drug: GSK5733584Drug: Bevacizumab

Module 3 (GSK5733584 + Anticancer therapy 3 +/- Dostarlimab or Bevacizumab)

EXPERIMENTAL
Drug: GSK5733584Drug: DostarlimabDrug: BevacizumabDrug: Anticancer therapy 3

Module 4 (GSK5733584 + Anticancer therapy 4 +/- Dostarlimab or Bevacizumab)

EXPERIMENTAL
Drug: GSK5733584Drug: DostarlimabDrug: BevacizumabDrug: Anticancer therapy 4

Interventions

GSK5733584 will be administered intravenously (IV).

Module 1 (GSK5733584 +/- Dostarlimab) Endometrial CancerModule 2 (GSK5733584 +/- Bevacizumab) Ovarian CancerModule 3 (GSK5733584 + Anticancer therapy 3 +/- Dostarlimab or Bevacizumab)Module 4 (GSK5733584 + Anticancer therapy 4 +/- Dostarlimab or Bevacizumab)

Dostarlimab will be administered IV.

Module 1 (GSK5733584 +/- Dostarlimab) Endometrial CancerModule 3 (GSK5733584 + Anticancer therapy 3 +/- Dostarlimab or Bevacizumab)Module 4 (GSK5733584 + Anticancer therapy 4 +/- Dostarlimab or Bevacizumab)

Bevacizumab will be administered IV.

Module 2 (GSK5733584 +/- Bevacizumab) Ovarian CancerModule 3 (GSK5733584 + Anticancer therapy 3 +/- Dostarlimab or Bevacizumab)Module 4 (GSK5733584 + Anticancer therapy 4 +/- Dostarlimab or Bevacizumab)

Anticancer therapy 3 will be administered IV.

Module 3 (GSK5733584 + Anticancer therapy 3 +/- Dostarlimab or Bevacizumab)

Anticancer therapy 4 will be administered IV.

Module 4 (GSK5733584 + Anticancer therapy 4 +/- Dostarlimab or Bevacizumab)

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Participants must be 18 years of age inclusive or older, at the time of signing the informed consent, or the legal age of consent in the jurisdiction in which the study is taking place.
  • Participant capable of giving signed informed consent including compliance with the requirements and restrictions listed in the Informed consent form (ICF) and in this protocol.
  • Participants with pathologically confirmed advanced solid tumor specific for study arms (key local diagnostic molecular and/or immunophenotyping testing results/tumor cell phenotype results for confirmed diagnosis should be provided) with no more than 4 lines of prior systemic therapies. Please note:
  • Adjuvant +/- neoadjuvant considered one line of therapy
  • Maintenance therapy will be considered as part of the preceding line of therapy (i.e., not counted independently)
  • Unplanned addition or switching to a new drug in a different class is considered a separate line of therapy. If an agent in a regimen is switched to another agent in the same class due to toxicity or intolerance (e.g. hypersensitivity reaction) this is considered part of the same line (i.e. not counted independently).
  • Requirements for tumor tissue samples: Archival or fresh tumor tissue is required for retrospective central assessment of B7H4 expression by immunohistochemistry (IHC) and other biomarker analysis. The archival tumor tissue should be from the most recent procedure (ideally obtained after the last anti-cancer treatment). If an archival tissue is not available a new biopsy should be performed, and the newly obtained tissue provided.
  • Participants have at least one target lesion as assessed per RECIST 1.1. A target lesion is defined as a measurable lesion that has not undergone locoregional treatment such as irradiation or that has unequivocal progression following locoregional treatment, with the longest diameter of ≥ 10 millimeter (mm) at Baseline (for lymph node lesions, the short axis should be ≥ 15 mm).
  • Participants have a life expectancy of at least 12 weeks per investigator assessment based on disease burden and extent of supportive care needed.
  • a. Participants with histologically documented, advanced (metastatic and/or unresectable) or recurrent endometrial cancer who have failed in adequate standard treatments, do not have effective standard treatment or are intolerant to standard of care, and who are not candidates for further curative external radiotherapy or brachytherapy.
  • Diagnosis of endometrial cancer with confirmed mismatch repair proficient (MMRp) or microsatellites stable (MSS) tumor status by local test.
  • Participants who have progressed on or are intolerant to at least 1 line of standard prior systemic therapy (including neoadjuvant or adjuvant as prior line), and who are not candidates for curative external radiotherapy or brachytherapy. Maintenance therapy will be considered part of the preceding line of therapy (i.e, not counted independently).
  • Participants naïve to anti-programmed death protein 1 and/or programmed death ligand 1 (PD\[L\]-1) anti-cancer therapy.
  • a. Participants with histologically or cytologically confirmed advanced epithelial ovarian cancer/fallopian tube/peritoneal cancer (any epithelial histology - mucinous, clear cell, carcinosarcoma, high/low grade serous, endometrioid) who have failed in adequate standard treatments, do not have effective standard treatment or are intolerant to standard of care.
  • Participants whose advanced ovarian cancer/fallopian tube/peritoneal cancer has relapsed more than 6 months from the last dose of platinum before enrollment, i.e., platinum sensitive.
  • +12 more criteria

You may not qualify if:

  • Has a second malignancy (except disease under study) that has progressed or required active treatment within the past 24 months except for basal cell or squamous cell carcinomas of the skin or in-situ carcinomas \[e.g., breast, cervix, bladder\] that have been resected with no evidence of metastatic disease.
  • Has any history of prior allogenic or autologous bone marrow transplant or other solid organ transplant.
  • Has known sensitivity to study intervention components, GSK5733584 (antibody-drug conjugate, antibody, free cytotoxin GSK5757810A) and combination partner, or its excipients or other allergy that, in the opinion of the investigator, contraindicates participation in the study.
  • Has any following cardiological examination abnormality:
  • history in prior year of clinically significant or uncontrolled cardiac disease, acute myocardial infarction, or clinically significant arrhythmia not controlled by standard of care therapy.
  • Corrected QT Interval (QTcF) \>450 millisecond (msec) or QTcF \>480 msec for participants with bundle branch block
  • Any evidence of current interstitial lung disease (ILD) or pneumonitis or a prior history of ILD or non-infectious pneumonitis.
  • Clinically significant bleeding symptoms, significant bleeding tendency, or bleeding tumors within 1 month prior to the first dose of study treatment.
  • Serious or poorly controlled hypertension, including history of hypertensive crisis, hypertensive encephalopathy; adjustment of antihypertensive medications due to poor blood pressure control within 2 weeks prior to the first dose of study treatment; systolic blood pressure ≥ 160 millimeter of mercury (mmHg) or diastolic blood pressure ≥ 100 mmHg during screening period.
  • Has any active renal condition (e.g., infection, requirement for dialysis, or any other active significant renal condition or dehydrated condition that could affect the participant's safety).
  • Participants with known history of Human immunodeficiency virus (HIV).
  • Has an Alanine transaminase (ALT) value \>2.5x Upper Limit of Normal (ULN) and for participants with documented liver metastases/tumor infiltration has an ALT value \>5x ULN.
  • Has a total bilirubin value \>1.5x ULN.
  • Has received treatment with any cytotoxic chemotherapy drugs or other anti-tumor drugs (including endocrine therapy, molecular targeted therapy, immunotherapy, biotherapy, and investigational drug) within 30 days or 5 half-lives, whichever is shorter of a medicinal product prior to the first dose of study drug; or need to continue these drugs during the study.
  • Use of strong or moderate inhibitors or inducers of CYP3A4, CYP2D6 and inhibitors or inducers of P-gp, and breast cancer resistance protein (BCRP) within 14 days prior to the first dose of study drug; or in need of continuing treatment with these drugs during the study.
  • +1 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (56)

GSK Investigational Site

Buenos Aires, C1280AEB, Argentina

RECRUITING

GSK Investigational Site

CABA, C1187, Argentina

RECRUITING

GSK Investigational Site

Viedma, R8500ACE, Argentina

RECRUITING

GSK Investigational Site

Liverpool, New South Wales, 2170, Australia

RECRUITING

GSK Investigational Site

Wollongong, New South Wales, 2500, Australia

RECRUITING

GSK Investigational Site

Brussels, 1200, Belgium

RECRUITING

GSK Investigational Site

Ghent, 9000, Belgium

RECRUITING

GSK Investigational Site

Leuven, 3000, Belgium

RECRUITING

GSK Investigational Site

Liège, 4000, Belgium

RECRUITING

GSK Investigational Site

Natal, 59075-740, Brazil

RECRUITING

GSK Investigational Site

Porto Alegre, 90020-090, Brazil

RECRUITING

GSK Investigational Site

São Paulo, 01246-000, Brazil

RECRUITING

GSK Investigational Site

Vitória, 29043-260, Brazil

RECRUITING

GSK Investigational Site

Toronto, Ontario, M5G 2M9, Canada

RECRUITING

GSK Investigational Site

Montreal, Quebec, H2X 0A9, Canada

RECRUITING

GSK Investigational Site

Montreal, Quebec, H4A 3J1, Canada

RECRUITING

GSK Investigational Site

Copenhagen, 2100, Denmark

RECRUITING

GSK Investigational Site

Helsinki, 00029, Finland

RECRUITING

GSK Investigational Site

Tampere, 33520, Finland

RECRUITING

GSK Investigational Site

Montpellier, 34298, France

RECRUITING

GSK Investigational Site

Pierre-Bénite, 69495, France

RECRUITING

GSK Investigational Site

Villejuif, 94805, France

RECRUITING

GSK Investigational Site

München, 81377, Germany

RECRUITING

GSK Investigational Site

Athens, 11528, Greece

RECRUITING

GSK Investigational Site

Athens, 12462, Greece

RECRUITING

GSK Investigational Site

Pylaia Thessaloniki, 570 01, Greece

RECRUITING

GSK Investigational Site

Thessaloniki, 55236, Greece

RECRUITING

GSK Investigational Site

Chiba, 277-8577, Japan

RECRUITING

GSK Investigational Site

Fukuoka, 811-1395, Japan

RECRUITING

GSK Investigational Site

Tokyo, 104-0045, Japan

RECRUITING

GSK Investigational Site

Tokyo, 135-8550, Japan

RECRUITING

GSK Investigational Site

Amsterdam, 1066 CX, Netherlands

RECRUITING

GSK Investigational Site

Rotterdam, 3015 GD, Netherlands

RECRUITING

GSK Investigational Site

Oslo, 0379, Norway

RECRUITING

GSK Investigational Site

Panama City, Panama

RECRUITING

GSK Investigational Site

Panama City, Panama

RECRUITING

GSK Investigational Site

Punta Pacifica Panama City Panama, Panama

RECRUITING

GSK Investigational Site

Józefów, 05-410, Poland

RECRUITING

GSK Investigational Site

Warsaw, 01-748, Poland

RECRUITING

GSK Investigational Site

Seoul, 05505, South Korea

RECRUITING

GSK Investigational Site

Seoul, 120-752, South Korea

RECRUITING

GSK Investigational Site

Barcelona, 08023, Spain

RECRUITING

GSK Investigational Site

Barcelona, 08035, Spain

RECRUITING

GSK Investigational Site

Barcelona, 08036, Spain

RECRUITING

GSK Investigational Site

Madrid, 28033, Spain

RECRUITING

GSK Investigational Site

Madrid, 28041, Spain

RECRUITING

GSK Investigational Site

Madrid, 28050, Spain

RECRUITING

GSK Investigational Site

Málaga, 29010, Spain

RECRUITING

GSK Investigational Site

Valencia, 46009, Spain

RECRUITING

GSK Investigational Site

Zaragoza, 50009, Spain

RECRUITING

GSK Investigational Site

Stockholm, 17164, Sweden

RECRUITING

GSK Investigational Site

Ankara, 06590, Turkey (Türkiye)

RECRUITING

GSK Investigational Site

Ankara, 6170, Turkey (Türkiye)

RECRUITING

GSK Investigational Site

Istanbul, 34010, Turkey (Türkiye)

RECRUITING

GSK Investigational Site

Glasgow, G12 0YN, United Kingdom

RECRUITING

GSK Investigational Site

London, NW1 2BU, United Kingdom

RECRUITING

MeSH Terms

Conditions

Neoplasms

Interventions

dostarlimabBevacizumab

Intervention Hierarchy (Ancestors)

Antibodies, Monoclonal, HumanizedAntibodies, MonoclonalAntibodiesImmunoglobulinsImmunoproteinsBlood ProteinsProteinsAmino Acids, Peptides, and ProteinsSerum GlobulinsGlobulins

Central Study Contacts

US GSK Clinical Trials Call Center

CONTACT

EU GSK Clinical Trials Call Center

CONTACT

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

January 22, 2025

First Posted

January 28, 2025

Study Start

March 4, 2025

Primary Completion (Estimated)

December 17, 2027

Study Completion (Estimated)

April 5, 2028

Last Updated

October 14, 2025

Record last verified: 2025-10

Data Sharing

IPD Sharing
Will share

Study Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/About\_GSK\_Patient\_Level\_Data\_Sharing\_Final\_13July2023.pdf

Shared Documents
STUDY PROTOCOL, SAP, ICF, CSR
Time Frame
Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or asset(s) with development terminated across all indications.
Access Criteria
Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months, but an extension may be granted, when justified, for up to 6 months.
More information

Locations