Phase 2b of RAPA-201 Cell Therapy in Post-PD-(L)-1 Melanoma

Inclusion Criteria: 1. Male or female patients ≥ 18 years of age. 2. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 and an estimated life expectancy of ≥ 3 months. 3. Patients with unresectable or metastatic melanoma (Stage IIIc or Stage IV). 4. Prior to enrollment, documented refractory status to the most recent regimen, which must include an anti-PD-(L)1 monoclonal antibody, as defined by lack of response after at least two cycles of therapy or relapse within 12-months of initiation of the anti-PD- (L)1-containing therapy. 5. For patients with BRAF V600 mutation-positive tumors, prior therapy with a BRAF inhibitor alone or in combination with a MEK inhibitor. 6. Presence of measurable disease to permit monitoring by iRECISTv1.1 Criteria. 7. Must have a potential source of autologous T cells potentially sufficient to manufacture RAPA-201 cells, as defined by a circulating absolute lymphocyte count (ALC) of ≥ 500 cells/μL. 8. Patients must be ≥ two weeks from last solid tumor cancer chemotherapy, major surgery, radiation therapy and/or participation in investigational trials. 9. Patients must have recovered from clinical immunotherapy-related toxicities \[resolution of CTCAE (v5) toxicity to a value of ≤ 1; with the exception of alopecia, vitiligo, and endocrinopathy stable on hormone replacement\]. 10. Hematologic parameters of: Absolute neutrophil count (ANC) of ≥ 1500 cells/μL, Platelet count ≥ 100,000 cells/μL, and Hemoglobin of ≥ 9 grams/μL. 11. Calculated creatinine clearance of ≥ 40 mL/min. 12. Ejection fraction (EF) by MUGA or 2-D echocardiogram within institution normal limits, with an EF level of ≥ 45%. 13. Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) ≤ 3 x upper limit of normal (ULN) (or ≤ ULN if patient has liver metastasis). 14. Bilirubin ≤ 2.0 mg/dL (if Gilbert\'s disease, ≤ 3.0 mg/dL). 15. No history of abnormal bleeding tendency (as defined by any inherited coagulation defect or history of internal bleeding). 16. Voluntary written consent must be given before performance of any study related procedure not part of standard medical care, with the understanding that consent may be withdrawn by the patient at any time without prejudice to future medical care. Exclusion Criteria 1. Other active malignancy (except non-melanoma skin cancer). 2. Life expectancy \< 3 months. 3. Seropositivity for HIV, hepatitis B, or hepatitis C, unless such conditions are in stable condition using adequate treatment. 4. Uncontrolled hypertension. 5. Cerebrovascular accident within 6 months of enrollment. 6. Myocardial infarction within 6 months of enrollment. 7. NYHA class III/IV congestive heart failure. 8. Uncontrolled angina/ischemic heart disease. 9. Cancer metastasis to the central nervous system, unless such metastasis has been adequately treated. 10. Pregnant or breastfeeding patients. 11. Women of childbearing potential, or males who have a partner of childbearing potential, who are unwilling to practice contraception. 12. Patients may be excluded at the discretion of the PI or if it is deemed that allowing participation would represent an unacceptable medical or psychiatric risk.