A Clinical Trial of Ifinatamab Deruxtecan in People With Advanced Esophageal Cancer (MK-3475-06F)

Inclusion Criteria: * Has a histologically or cytologically confirmed diagnosis of unresectable locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) * Has disease progression after 1 or 2 prior lines of systemic therapy for unresectable locally advanced or metastatic ESCC * Has measurable disease * If infected with human immunodeficiency virus (HIV), has well-controlled HIV on antiretroviral therapy * Has adequate organ function Exclusion Criteria: * Has histologically or cytologically confirmed adenocarcinoma or adenosquamous carcinoma subtype * Has uncontrollable pleural effusion, pericardial effusion, or ascites requiring frequent drainage or medical intervention * Has clinically significant corneal disease * Has any of the following within 6 months before screening: cerebrovascular accident, transient ischemic attack, other arterial thromboembolic event * If infected with HIV, has a history of Kaposi's sarcoma and/or Multicentric Castleman's Disease * Has uncontrolled or significant cardiovascular disease * Has a known additional malignancy that is progressing or has required active treatment within the past 3 years * Has known active central nervous system metastases and/or carcinomatous meningitis * Has a history of (noninfectious) pneumonitis/interstitial lung disease irrespective of requiring steroids or has any current pneumonitis/interstitial lung disease or has suspected pneumonitis/interstitial lung disease * Has active infection requiring s…