A Phase 1 interventional study of GSK5764227 and Bevacizumab in Neoplasms, sponsored by GlaxoSmithKline. Recruiting at 22 sites in 6 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by GlaxoSmithKline · Phase 1, Interventional, and Treatment
The goal of this clinical trial is to test a new medicine called GSK5764227, which delivers a toxin directly to cancer cells to destroy them while sparing healthy cells. The study will combine GSK5764227 with standard treatments to evaluate its safety, examine how the body processes it, check if it triggers any immune responses, and assess whether it can shrink or control cancer.
10,818 studies on the registry are indexed under Neoplasms; 2,324 are open to participants now.
This study's planned enrollment of 83 is above the median of 60 across 7,703 interventional studies indexed under Neoplasms.
Browse Neoplasms studies →GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 118 are open to participants now.
Of its 264 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: GSK5764227 · Drug: Bevacizumab
Drug: GSK5764227 · Drug: Bevacizumab · Drug: Fluorouracil · Drug: leucovorin
Drug: GSK5764227 · Drug: Enzalutamide
Participants will receive GSK5764227.
Participants will receive bevacizumab.
Participants will receive fluorouracil.
Participants will receive leucovorin.
Participants will receive enzalutamide.
Number of participants with adverse events (AEs), Serious AEs (SAEs), AE of special interest (AESIs) and AEs leading to dose modifications
Time frame: Up to approximately 31 weeks
Number of participants with AEs, SAEs, AESIs, and AEs leading to dose modifications by severity
Time frame: Up to approximately 31 weeks
Number of participants with dose limiting toxicities (DLTs)
Time frame: Up to approximately 31 weeks
Number of participants with clinically significant changes in Vital Signs, Body Weight, Laboratory Tests [Hematology, Clinical Chemistry, Urinalysis], Cardiac Function [ECG], and Eastern Cooperative Oncology Group (ECOG) performance status
Time frame: Up to approximately 31 weeks
Plasma concentration of GSK5764227 [conjugated antibody and payload (GSK5757810)
Time frame: Up to approximately 112 weeks
Number of participants with anti-drug antibody (ADA) against GSK5764227
Time frame: Up to approximately 112 weeks
Number of participants with neutralising antibody (NAb) against GSK5764227
Time frame: Up to approximately 112 weeks
Titer of ADA against GSK5764227
Time frame: Up to approximately 112 weeks
Objective Response Rate (ORR)
ORR is defined as the proportion of participants who have achieved best observed response (BOR) of confirmed complete response (CR) or partial response (PR) as assessed by investigator, according to Response Evaluation Criteria in Solid Tumors (RECIST 1.1) for Cohort A or per Prostate Cancer Clinical Trials Working Group 3 (PCWG3) for Cohort B.
Time frame: Up to approximately 112 weeks
Disease control Rate (DCR18)
DCR18 is defined as the proportion of participants who have achieved CR or PR, or stable disease (SD) of ≥17 weeks as assessed by investigator according to PCWG3 for Cohort B.
Time frame: Up to approximately 112 weeks
Duration of Response (DoR)
DOR is defined as the time from the date of the first documented objective response (CR/PR) as assessed by investigator according to RECIST 1.1 for cohort A or PCWG3 for cohort B, until the date of the first documented disease progression (PD) or death due to any cause, whichever is earlier.
Time frame: Up to approximately 112 weeks
Progression free survival (PFS)
PFS is defined as the time from the date of first dose until the earliest date of documented disease progression as assessed by investigator according to RECIST 1.1 for cohort A.
Time frame: Up to approximately 112 weeks
Radiographic progression-free survival (rPFS)
rPFS is defined as the time from the date of first dose until the earliest date of documented PD per PCWG3-modified RECIST 1.1 (soft tissue lesion assessment) and/or PCWG3 bone lesion assessment for cohort B or death due to any cause.
Time frame: Up to approximately 112 weeks
Prostate-specific antigen 50 (PSA50)
PSA50 is defined as percentage of participants with a decrease of \>=50% in the PSA concentration from the baseline PSA value, confirmed at least 3 weeks later (cohort B)
Time frame: Up to approximately 112 weeks
Plan to share: Yes — 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/gsk-patient-level-data-sharing-july2025.pdf
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
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.
Data sharing details ↗ · www.gsk-studyregister.com
No publications or documents are linked to this record.
Started Dec 2025 (actual). Primary completion is estimated for Feb 2028, 26 months after the start.
Of 677 industry-sponsored phase 1 interventional studies under Neoplasms, half reached primary completion within 38 months of starting (the median), counting those still running; a quarter within 22 and three quarters within 61. This study's planned 26 months is below that.
Counting every sponsor, half of 903 studies reached it within 40 months; a quarter within 23 and three quarters within 64.
Neoplasms covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.
Since we started tracking on Sep 25, 2026, the dates moved once, on Sep 25, 2026: primary completion Jul 2026 → Feb 2028 and completion Sep 2028 → May 2030.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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Studies of the drug tested here: Risvutatug rezetecan