A Phase 1, Multiple-Dose Study to Evaluate the Safety and Tolerability of XmAb819 in Subjects with Relapsed or Refractory Clear Cell Renal Cell Carcinoma

Inclusion Criteria

• Subjects must have measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST 1.1) as assessed by the local site investigator. Lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions.
• Subjects who have relapsed and refractory ccRCC with evidence of disease progression on standard-of-care therapies
• ECOG performance status of 0 or 1.
• All subjects must have adequate tumor sample available (slides or archival FFPE blocks)

Exclusion Criteria

• Prior treatment with an investigational anti-ENPP3/CD203c therapy
• History of serious allergic or anaphylactic/hypersensitivity reaction to monoclonal antibody therapy
• Systemic antineoplastic therapy within 5 half-lives on the first dose of study treatment.
• Failure to recover from any clinically significant toxicity related to previous anticancer treatment
• Have known active central nervous system metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate provided they are radiologically stable,
• Active known autoimmune disease (except that subjects are permitted to enroll if they have vitiligo; type 1 diabetes mellitus; residual hypothyroidism due to an autoimmune condition that is treatable with hormone replacement therapy only; psoriasis, atopic dermatitis, or another autoimmune skin condition that is managed without systemic therapy; or arthritis that is managed without systemic therapy beyond oral acetaminophen and nonsteroidal anti-inflammatory drugs)
• Evidence of any serious infection requiring IV anti-infective treatment within 14 days prior to the first dose of study drug
• Have a known additional malignancy that is progressing or has required active treatment within the past 2 years