Neoadjuvant Tebentafusp in Patients With Metastatic Uveal Melanoma

Inclusion Criteria: 1. Patients must have histologically confirmed metastatic uveal melanoma with Human leukocyte antigen-A\*0201 positive determined by local assay. 2. Patients with histologically proven metastatic uveal melanoma in the liver with reectable or potentially resectable liver metastases evaluated by imaging in a multidisciplinary committee. Metastasis can be considered resectable by any of the following: 1. Minor resection (i.e., less than a hemihepatectomy) 2. Major resection (i.e., hemihepatectomy or extended hepatectomy) 3. Bilobar resection (including atypical resection). 3. Must meet the following criteria related to prior treatment: 1. No prior systemic therapy in the metastatic or advanced setting including chemotherapy, immunotherapy, or targeted therapy. 2. No prior local, liver-directed therapy including chemotherapy, radiotherapy, radiofrequency ablation (RFA), or embolization. 3. Prior neoadjuvant or adjuvant therapy is allowed provided it was administered in the curative setting in patients with localized disease. 4. Institutional Review Board (IRB)/Independent Ethics Committee (IEC) approved written and signed informed consent. 5. Male or female patients age ≥ 18 years of age at the time of informed consent. 6. Eastern Cooperative Oncology Group Performance Status (ECOG-PS) 0-1 7. Adequate organ function as defined below (without transfusion): 1. Hemoglobin ≥9.0 g/dL. 2. Absolute neutrophil count (ANC) \>1.5 x 109/L (\> 1500 per mm3). 3. Platelet count ≥ 100 x 109/L (\>75,000 per mm3). 4. Serum bilirubin ≤1.5 x institutional upper limit of normal (ULN). This will not apply to patients with confirmed Gilbert's syndrome (persistent or recurrent hyperbilirubinemia that is predominantly unconjugated in the absence of hemolysis or hepatic pathology), who will be allowed only in consultation with the Coordinating Investigator. 5. Both AST and ALT must be \< 5 x ULN. 6. Creatinine clearance ⩾50 ml/min calculated by Cockcroft-Gault (Table 4) or another validated method. 7. Potassium, magnesium, corrected calcium or phosphate abnormality of National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) \> grade 1. Exclusion Criteria: 1. Presence of extrahepatic disease. 2. Patients with concomitant malignancy other than non-melanoma skin cancer, or superficial bladder cancer controlled with local treatment. Patients with prior malignancy must have been disease free for 5 years. 3. History of severe hypersensitivity reactions (eg, anaphylaxis) to other biologic drugs or monoclonal antibodies. 4. Clinically significant cardiac disease or impaired cardiac function, including any of the following: 1. Clinically significant and/or uncontrolled heart disease such as congestive heart failure (New York Heart Association grade ≥ 2), uncontrolled hypertension, or clinically significant arrhythmia currently requiring medical treatment. 2. QTcF \> 470 msec on screening electrocardiogram (ECG) or congenital long QT syndrome. 3. Acute myocardial infarction or unstable angina pectoris \< 6 months prior to Screening. 5. History of adrenal insufficiency. 6. History of interstitial lung disease 7. History of pneumonitis that required corticosteroid treatment or current pneumonitis 8. History of colitis or inflammatory bowel disease. 9. Active infection requiring systemic antibiotic therapy. Patients requiring systemic antibiotics for infection must have completed therapy at least 1 week prior to the first dose of study drug. 10. Known history of human immunodeficiency virus (HIV) infection. Testing for HIV status is not necessary unless clinically indicated or if required by local regulations. 11. Active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection per institutional protocol. Testing for HBV or HCV status is not necessary unless clinically indicated. 12. Previous treatment with Tebentafusp. 13. Patients receiving systemic steroid therapy or any other immunosuppressive medication at any dose level. Local steroid therapies (eg, otic, ophthalmic, intra-articular or inhaled medications) are acceptable. 14. Major surgery within 2 weeks of the first dose of study drug (minimally invasive procedures such as bronchoscopy, tumor biopsy, insertion of a central venous access device, and insertion of a feeding tube are not considered major surgery and are not exclusionary). 15. Use of hematopoietic colony-stimulating growth factors (e.g., G-CSF, GMCSF, M-CSF) ≤ 2 weeks prior to the start of study drug. Patients must have completed therapy with hematopoietic colony-stimulating factor at least 2 weeks before the first dose of study drug is given. An erythroid-stimulating agent is allowed as long as it was initiated at least 2 weeks prior to the first dose of study treatment and the patient is not red blood cell transfusion dependent. 16. Hypersensitivity to the active substance of tebentafusp or to any of its excipients, including: Citric acid monohydrate (E330) Di-sodium hydrogen phosphate (E339) Mannitol (E421) Trehalose Polysorbate 20 (E432). 17. Patients whose circumstances will not permit study completion or adequate follow up. 18. Pregnant, likely to become pregnant, or lactating women (where pregnancy is defined as the state of a female after conception and until the termination of gestation). 19. Women of child-bearing potential who are sexually active with a non-sterilized male partner, defined as all women physiologically capable of becoming pregnant, unless they are using highly effective contraception during study treatment, and must agree to continue using such precautions for 1 week after the final dose of investigational product. Highly effective methods of contraception are described in Appendix 5. 20. Male patients must be surgically sterile or use double barrier contraception methods from enrollment through treatment and for 1 week following administration of the last dose of study drug.