A Phase 3 interventional study of Risvutatug rezetecan (Ris-Rez) and Topotecan in Neoplasms, Lung, sponsored by GlaxoSmithKline. Recruiting at 148 sites in 25 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by GlaxoSmithKline · Phase 3, Interventional, and Treatment
In this study researchers are testing Risvutatug rezetecan also known as (Ris-Rez) a new medicine that targets specific proteins (B7-H3) on cancer cells, thereby reducing the cancer's ability to grow and spread. This study specifically aims to evaluate how well Ris-Rez works in treating relapsed SCLC compared to standard treatment topotecan, by checking whether Ris-Rez makes cancers smaller or disappear completely and if it helps participants live longer. The study is also assessing whether Ris-Rez is safe and tolerated well by participants compared to topotecan and provide a better understanding of the main side effects of both drugs. Participants with relapsed SCLC will be randomly divided into two groups: one group receiving Ris-Rez and the other receiving topotecan.
1,301 studies on the registry are indexed under Small Cell Lung Carcinoma; 367 are open to participants now.
This study's planned enrollment of 420 is above the median of 56 across 1,077 interventional studies indexed under Small Cell Lung Carcinoma.
Browse Small Cell Lung Carcinoma 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.
Compared within Small Cell Lung Carcinoma, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Lung Neoplasms. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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.
Participants are eligible to be included in the study only if all of the following criteria apply:
Exclusion Criteria:
Participants are excluded from the study if any of the following criteria apply:
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
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 other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
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.
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.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biological: Risvutatug rezetecan (Ris-Rez)
Drug: Topotecan
Ris-Rez will be administered
Topotecan will be administered
Overall Survival (OS)
OS is defined as the time from the date of randomization to the date of death by any cause
Time frame: Up to approximately 113 weeks
Brain PFS
Brain PFS is defined as the time from the date of randomization to the date of first documented PD per modified Response assessment in neuro-oncology (RANO-BM) by BICR assessment or death from any cause, whichever occurs first in participants with history of brain metastasis or presence of brain metastasis at baseline
Time frame: Up to approximately 139 weeks
Change from baseline in cough
Validated questionnaires will be used for the assessment
Time frame: Up to approximately 18 weeks
Change from baseline in dyspnea
Validated questionnaires will be used for the assessment
Time frame: Up to approximately 18 weeks
Change from baseline in chest pain
Validated questionnaires will be used for the assessment
Time frame: Up to approximately 18 weeks
Time to clinical deterioration in physical functioning
Time to clinical deterioration in physical functioning will be measured using validated questionnaires
Time frame: Up to approximately 139 weeks
Objective Response Rate (ORR)
ORR is defined as the percentage of participants with a confirmed complete (CR) or confirmed partial response (PR) per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 by investigator/Blinded Independent Central Review (BICR) assessment
Time frame: Up to approximately 139 weeks
Duration of Response (DoR)
DoR is defined as the time from the date of first documented objective response (CR or PR) per RECIST 1.1 by investigator/BICR assessment to the date of first documented PD per RECIST 1.1 by investigator/BICR assessment or death due to any cause, whichever comes first
Time frame: Up to approximately 139 weeks
Progression-free survival (PFS)
PFS is defined as the time from the date of randomization to the date of first documented Progressive disease (PD) per RECIST 1.1 by investigator/BICR assessment or death from any cause, whichever occurs first
Time frame: Up to approximately 139 weeks
Disease control rate (DCR) 12
DCR12 is defined as the percentage of participants who have a Best objective response (BOR) of confirmed CR, confirmed PR, or Stable Disease (SD) for a duration of at least 11 weeks, per RECIST 1.1 by investigator/BICR assessment
Time frame: Up to approximately 11 weeks
Brain DoR
Brain DoR is defined as the time from the first documented objective response (CR/PR according to modified RANO-BM BICR assessment) until the time of first documentation of disease progression or death, whichever occurs first, in participants with a history of brain metastasis or presence of brain metastasis at baseline
Time frame: Up to approximately 139 weeks
Brain ORR
Brain ORR is defined as the percentage of participants with confirmed brain CR or confirmed brain PR per modified RANO-BM BICR assessment in participants with a history of brain metastasis or presence of brain metastasis at baseline
Time frame: Up to approximately 139 weeks
Brain DCR12
Brain DCR12 is defined as the percentage of participants with an intracranial BOR of confirmed CR, confirmed PR or SD after the date of randomization, per modified RANO-BM BICR assessment in participants with a history of brain metastasis or presence of brain metastasis at baseline
Time frame: Up to approximately 11 weeks
Time to brain progression
Time to brain progression is defined as the time from the date of randomization to the date of first documented brain PD per modified RANO-BM BICR assessment in participants with a history of brain metastasis or presence of brain metastasis at baseline.
Time frame: Up to approximately 139 weeks
Number of participants with Adverse events (AEs), Serious Adverse Events (SAEs) and Adverse events of special interest (AESIs) by severity
Time frame: Up to approximately 139 weeks
Number of participants with AEs leading to dose modifications or study intervention discontinuation
Time frame: Up to approximately 139 weeks
Number of participants with a change from baseline in vital signs
Number of participants will be assessed.
Time frame: Baseline (Day -1) and up to approximately 139 weeks
Number of participants with a change from baseline in laboratory parameters (hematology and clinical chemistry)
Number of participants will be assessed.
Time frame: Baseline (Day -1) and up to approximately 139 weeks
Number of participants with a change from baseline in cardiac function [Electrocardiogram (ECG)
Number of participants will be assessed.
Time frame: Baseline (Day -1) and up to approximately 139 weeks
Number of participants with a change from baseline in Eastern Cooperative Oncology Group (ECOG) performance status
Number of participants will be assessed.
Time frame: Baseline (Day -1) and up to approximately 139 weeks
Observed PK concentrations of Ris-Rez (conjugated antibody and small molecule payload)
Time frame: Up to approximately 139 weeks
Number of participants with Antidrug antibody (ADA) or Neutralizing Antibody (NAb)
Time frame: Up to approximately 139 weeks
Titers of ADA against Ris-Rez
Time frame: Up to approximately 139 weeks
Participant reported experience with study treatment
Participant reported outcomes assessing symptoms, daily functioning, and overall health status during study treatment will be measured using validated questionnaires
Time frame: Up to approximately 139 weeks
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Showing the first 100 of 148 sites across 25 countries. Choose a country and city above to see the rest.
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 Aug 2025 (actual). Primary completion is estimated for Nov 2027, 26 months after the start.
Of 56 industry-sponsored phase 3 interventional studies under Small Cell Lung Carcinoma, half reached primary completion within 36 months of starting (the median), counting those still running; a quarter within 30 and three quarters within 44. This study's planned 26 months is below that.
Counting every sponsor, half of 69 studies reached it within 44 months; a quarter within 31 and three quarters within 48.
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.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Studies of the drug tested here: Risvutatug rezetecan