A Study of GSK5764227 in Participants With Relapsed Small Cell Lung Cancer (SCLC)

Inclusion Criteria

Participants are eligible to be included in the study only if all of the following criteria apply:

• Adults >18 or the minimum legal adult age at the time the informed consent form is signed
• Has histologically or cytologically confirmed extensive-stage small cell lung cancer (ES-SCLC).
• Has received 1 prior platinum-based systemic therapy with a PD- (L)1 inhibitor for at least 2 cycles of therapy and a chemotherapy free-interval of >30 days, with documented progression. Participants with prior tarlatamab treatment in either the first- or second-line ES-SCLC setting are eligible.
• Has at least 1 target lesion per RECIST 1.1, as determined by the investigator.
• Is capable of giving signed informed consent, including compliance with the requirements and restrictions listed in the ICF and in the protocol.
• Has adequate organ function and an ECOG performance status of 0 or 1

Exclusion Criteria

Participants are excluded from the study if any of the following criteria apply:

• Pathological diagnosis of complex SCLC or transformed SCLC.
• Limited stage small cell lung cancer at diagnosis
• Has received any prior therapy with an Antibody-drug conjugate (ADC) with a Topoisomerase-1 (TOPO1)-inhibitor payload or treatments targeting B7-H3.
• Has known sensitivity to study intervention components or excipients or other allergy that, in the opinion of the investigator or medical monitor, contraindicates participation in the study.
• Has severe, uncontrolled or active cardiovascular disorders.
• Has clinically significant bleeding symptoms or significant bleeding tendency within 1 month prior to the first dose.
• Known active infectious diseases requiring systemic treatment or known Human immunodeficiency virus (HIV).
• Has symptomatic brain metastases or untreated progression exclusively due to brain metastasis during or after the last treatment prior to screening, evidence of leptomeningeal/meningeal/brainstem metastasis or evidence of spinal cord metastases.
• Has any evidence of current interstitial lung disease or pneumonitis or a prior history of ILD or non-infectious pneumonitis requiring high dose steroids.
• Has significant pulmonary disease or respiratory impairment (e.g., uncontrolled asthma/COPD, restrictive lung disease),
• Has active Hepatitis B or Hepatitis C