Study of ART0380 in Patients With Biologically Selected Solid Tumors

Inclusion Criteria: * Patients who have discontinued all previous treatments for cancer for at least 21 days or 5 half-lives (not including palliative radiotherapy at focal sites), whichever is shorter. Palliative radiotherapy must have completed 1 week prior to start of study treatment. * Resolution of all toxicities of prior therapy or surgical procedures to baseline or Grade 1 (except for hypothyroidism requiring medication, neuropathy, and alopecia, which must have resolved to Grade ≤2). * Have adequate organ function. * Patients of childbearing potential and patients with partners of childbearing potential are required to use highly effective contraception. * Have an estimated life expectancy of ≥12 weeks, in the judgment of the investigator. * Performance status of 0-1 on the Eastern Cooperative Oncology Group scale. * Have a non-irradiated tumor tissue sample (archival or newly obtained core biopsy of a tumor lesion) available. Inclusion Criteria specific to each Arm Inclusion Criteria for Arm 1 \[ART0380 monotherapy (endometrial cancer patients)\] * Persistent or recurrent EC with biological selection. * Patients should have received taxane/platinum chemotherapy unless contraindicated. * Measurable disease. Inclusion Criteria for Arm 2 \[ART0380 monotherapy (solid tumors patients)\] * Advanced or metastatic solid cancers of any histology with biological selection. * If a Programmed cell death protein-1 /Programmed death-ligand-1 inhibitor (e.g., pembrolizumab) i…