This is a Phase Ib, open-label study to determine the safety and preliminary efficacy of PRJ1-3024 in China subjects with unresectable local advanced or metastatic melanoma

The study will evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of PRJ1-3024 and will determine the recommended dose in China subjects with unresectable local advanced or metastatic melanoma.

PRJ1-3024 is a small molecular Hematopoietic progenitor kinase (HPK-1) inhibitor. It will be evaluated as an oral therapeutic that tests the anti-tumor activity in patients with unresectable or metastatic melanoma and has not yet been tested in humans.

Inclusion Criteria:• Histologically or cytologically confirmed locally advanced (unresectable) or metastatic melanoma (with the exception of ocular uveal melanoma). Patients who have progressed or relapsed after at least 1st-line systemic standard therapy.

• Male or non-pregnant, non-lactating female subjects aged ≥18 years.
• ECOG Performance Status 0~1.
• Has at least 1 measurable lesion as defined by RECIST 1.1 criteria.
• Life expectancy of ≥3 months, in the opinion of the Investigator.
• Able to take oral medications and willing to record daily adherence to investigational product.
• Adequate hematologic parameters.
• Adequate renal and hepatic function
• Able to understand and willing to sign a written informed consent form.
• Consent to provide archived tissue specimen or tissue sample.

Exclusion Criteria:• History of another malignancy.

• Known symptomatic brain metastases requiring >10 mg/day of prednisolone.
• Significant cardiovascular disease.
• Known active HBV, HCV, AIDS-related illness.
• Has received a live vaccine within 30 days.
• History of active autoimmune disorders, or ongoing immunosuppressive therapy.
• Continuance of toxicities due to prior radiotherapy or chemotherapy agents that do not recover to < Grade 2.
• Receiving concurrent anti-cancer therapy, investigational product, strong inhibitors or inducers of cytochrome P450 3A (CYP3A) .
• Prior treatment with other hematopoietic progenitor kinase 1 (HPK1) inhibitors.
• Allergy to the ingredients of study drug, or a history of other allergies which were judged by the investigator to be unsuitable for participation in the study.