A Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Clinical Activity of GSK5733584 for Injection in Participants With Advanced Solid Tumors

Inclusion Criteria:

• Males or females aged 18 years or older (≥18 years).

• Participants with pathologically confirmed advanced solid tumor (who have failed orare intolerant to standard of care).

• PROC cohort

1. Histologically documented, advanced (metastatic and/or unresectable) high-gradeserous/endometrioid ovarian, primary peritoneal, or fallopian tube cancer.

2. Must have received or are intolerant to 1 but no more than 3 lines of priorsystemic therapy.

3. Platinum-resistant disease, defined as progression or relapse within 6 monthsafter the completion of platinum-based therapy.

4. Must have had prior bevacizumab if the participant was considered a candidatefor this regimen and the regimen is locally available.

5. Participants with known Folate receptor-α (FR-α) expressing tumors must havereceived mirvetuximab soravtasine if the participants was considered acandidate for this regimen and the regimen is locally available.

6. Participants with known Breast cancer susceptibility gene (BRCA) mutated tumorsshould have received a Poly adenosine diphosphate-ribose polymerase (PARP)inhibitor if the participant was considered a candidate for this regimen andthe regimen is locally available.

7. Maintenance therapy will be considered part of the preceding line of therapy (ie, not counted independently).

• Endometrial cancer cohort

1. Histologically documented, advanced (metastatic and/or unresectable) orrecurrent endometrial cancer.

2. Must have received or are intolerant to 1 but no more than 2 lines of priorsystemic therapy.

3. Must have had prior platinum and PD(L)-1 inhibitor (in same regimen or inseparate regimens), if considered a candidate for this regimen and the regimenis locally available.

4. Maintenance therapy will be considered part of the preceding line of therapy (ie, not counted independently

5. All epithelial histologies are permitted including carcinosarcoma.

• Participants have at least one target lesion as assessed per the RECIST 1.1

• Tumor tissue from a newly obtained biopsy or archival tumor tissue is required forretrospective detection of B7 homolog 4 (B7-H4) expression by Immunohistochemistry (IHC) in central laboratory and other biomarker analysis. Tissue from a newlyobtained biopsy is preferred. If a newly obtained biopsy is not feasible, archivaltumor tissue within 2 years prior to the first dose of study drug is acceptable.

• Eastern Cooperative Oncology Group Performance Status (ECOG PS) score of 0 to 2 andno deterioration within 2 weeks before the first dose.

• Have a life expectancy of at least 12 weeks.

Exclusion Criteria:

• Have received any of B7-H4-targeted therapies.

• Have received any of cytotoxic chemotherapy drugs, anti-tumor traditional Chinesemedicines or other anti-tumor drugs within 28 days prior to the first dose of studydrug; or need to continue these drugs during the study.

• Have received locoregional radiation therapy within 2 weeks prior to the first doseof study drug; more than 30% of bone marrow irradiation or wide-field radiationtherapy within 4 weeks prior to the first dose of study treatment.

• Presence of pleural/abdominal effusion/ascites requiring clinical intervention;presence of pericardial effusion

• Major surgery within 4 weeks prior to the first dose of study treatment.

• Evidence of brain metastasis unless asymptomatic.

• Has inadequate bone marrow reserve or hepatic/renal functions.

• Mean Fridericia-corrected QT interval (QTcF) > 470 millisecond (msec) on restingECG.

• Evidence of current clinically significant arrhythmias or ECG abnormalities

• Risk factors of prolonged QTc or arrhythmia events,

• Left ventricular ejection fraction (LVEF) < 50%.

• Have severe, uncontrolled or active cardiovascular disorders, serious or poorlycontrolled hypertension, clinically significant bleeding symptoms or seriousarteriovenous thromboembolic events

• Any evidence of current Interstitial lung disease (ILD) or pneumonitis or a priorhistory of ILD or pneumonitis requiring high-dose systemic glucocorticoids.

• Have received prior therapy with topoisomerase inhibitors or topoisomerase inhibitorAntibody-drug conjugate (ADCs)

• PROC

1. Primary platinum refractory not permitted.

2. Non-epithelial carcinoma, clear-cell, mucinous, germ-cell, low-grade serous, orlow-grade endometrioid carcinoma not permitted.

• Endometrial cancer a. Mesenchymal tumors of the uterus (uterine sarcomas) notpermitted.