Phase 1a and Phase 2 Study for PK, PD, Safety and Preliminary Efficacy of ST-067

Inclusion Criteria:

Male and female patients aged ≥18 years
Must provide written informed consent and any authorizations required by local law
Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

Have histologically or cytologically confirmed diagnosis of advanced/metastatic solid tumor

For Phase 1a, the following solid tumors are allowed: Melanoma, Merkel cell, RCC, urothelial, NSCLC,TNBC, SCCHN, microsatellite instability high, high tumor mutation burden (Hi TMB) or mismatch repair deficient, gastric, cervical, endometrial, cutaneous squamous, small cell lung, esophageal, hepatocellular carcinoma and platinum resistant ovarian cancer.

For patients who have developed disease progression through standard therapy, or
For patients whom standard of care therapy that prolongs survival is unavailable or unsuitable (according to the investigator and after consultation with the Medical Monitor)

For Phase 2, the following solid tumors are allowed:

Melanoma, RCC, TNBC, NSCLC, SCCHN, and MSI-Hi tumors

Has at least 1 measurable lesion per RECIST 1.1 criteria which has not been biopsied or received prior irradiation
Has an accessible tumor for biopsy pre- and on-treatment (mandatory).

Exclusion Criteria:

History of another malignancy
Known symptomatic brain metastases requiring >10 mg/day of prednisolone
Significant cardiovascular disease
Significant ECG abnormalities
Any degree of respiratory compromise (from malignant or non-malignant disease)
Evidence of an ongoing systemic bacterial, fungal, or viral infection
Has received a live vaccine within 30 days
Major surgery within 4 weeks
Prior solid organ or bone marrow progenitor cell transplantation
Prior high dose chemotherapy requiring stem cell rescue
History of active autoimmune disorders
Ongoing immunosuppressive therapy, including systemic or enteric corticosteroids.
Treatment with an approved, systemic anticancer therapy or an investigational agent within 4 weeks of Day 1