Phase 1, Safety and Tolerability Study of XmAb541 and XmAb808 in Advanced Solid Tumors

Inclusion Criteria: * Age ≥ 18 years. * CLDN6+ tumor * Histological or cytological documentation of locally advanced, recurrent, or metastatic high grade serous ovarian carcinoma (HGSOC) including fallopian tube or primary peritoneal origin * Adequate Eastern Cooperative Oncology Group performance status * Life expectancy ≥ 3 months * Adequate organ function Exclusion Criteria: * Prior exposure to a CLDN6 targeting immune cell engager * Patients with treated brain metastases may participate, provided they are radiologically stable. * Active known or suspected autoimmune disease * Have any condition requiring systemic treatment with corticosteroids, prednisone equivalents, or other immunosuppressive medications within 14 days prior to first dose of study drug * Clinically significant cardiovascular, pulmonary or gastrointestinal disease * Active viral hepatitis B or hepatitis C