A Trial of Intratumoural Tigilanol Tiglate in Adult Participants With Stage IIIB to IV M1c Melanoma

Primary Objective 1. To evaluate the tumour responses of both injected and non injected tumours following treatment with intratumoural injections of tigilanol tiglate into one or more tumours (according to RECIST v1.1); and 2. To assess the tumour ablation rate following treatments with intratumoural injections of tigilanol tiglate. Secondary Objectives 1. To assess the tumour recurrence rate at injected tumour site(s); 2. To assess the safety and tolerability of intratumoural injections of tigilanol tiglate; 3. To assess the degree of wound healing at injection sites; and 4. To evaluate disease control by looking at Progression Free Survival (PFS) in melanoma participants receiving tigilanol tiglate injections over 36 months. Exploratory Objectives 1. To evaluate Overall Survival (OS) in melanoma participants receiving tigilanol tiglate injections over 36 months; 2. To assess the tumour microenvironment by looking at the degree of immune cell infiltration in non-injected tumours; and 3. To assess the Quality of Life (QoL) in melanoma participants receiving tigilanol tiglate injections.