A Study of Ceralasertib Monotherapy and Ceralasertib Plus Durvalumab in Patients With Melanoma and Resistance to PD-(L)1 Inhibition

Participants must have a histologically or cytologically confirmed diagnosis of unresectable or metastatic melanoma of cutaneous, acral or mucosal subtypeAvailability of an archival tumour sample and a fresh tumour biopsy taken at screening Patient must have received at least 1 prior immunotherapy (anti-PD-(L)1 ± anti-CTLA-4 [Cytotoxic T-lymphocyte-associated protein 4]) for a minimum of 6 weeks and no more than 2 prior regimens in the metastatic setting. Patients must have confirmed progression during treatment with a PD-(L)1 inhibitor +/- a CTLA-4 inhibitor. The interval between the last dose of anti-PD-(L)1, BRAF/MEK (B-Rapidly Accelerated Fibrosarcoma gene/mitogen-activated protein kinase gene) inhibitor and the first dose of the study regimen must be a minimum of 14 days Measurable disease by RECIST 1.1. Patients must have a life expectancy ≥3 months from proposed first dose date. Biopsy Sub-study: Consent to the provision of 3 mandatory tumour biopsies.