Tebentafusp in Molecular Relapsed Disease (MRD) Melanoma

TebeMRD is an unblinded non-randomised, open labelled, safety and efficacy study involving 2 patient cohorts: * A: Cutaneous melanoma with molecular relapsed disease (MRD) * B: Uveal melanoma with MRD Approximately 850 patients (600 cutaneous melanoma, 250 uveal melanoma) will be enrolled from 50 centres to screen for HLA-A\*0201 status and then followed for up to 24 months for MRD at those same centres. Patients identified with MRD will be invited to be treated with tebentafusp at up to 10 treating centres in the UK. Patients in cohorts A and B will receive up to six months of tebentafusp, administered weekly IV, and then will be followed-up for 12 months for molecular and clinical relapse. Patients will be in the pre-screening phase for determination of HLA-A\*0201 status for up to 2 weeks. Those patients who are positive for HLA-A\*0201 will be followed for MRD and will attend the clinical sites for 3 monthly testing for up to 24 months. Patients will leave the study if no molecular relapse is detected during the molecular screening period. When MRD is identified, patients will be evaluated for eligibility to enter the main study at one of up to 10 specialist treatment centres, where patients will enter the screening period for determination of eligibility to start tebentafusp administration within 6 weeks. After a maximum 6 months treatment patients will be followed up for 12 months, or until the study is completed, if this is longer.