The invention generally relates to sonodynamic therapy using microbubble-sonosensitiser complexes and, more specifically, to such therapy for the treatment of deeply-sited tumours and associated metastatic disease. In particular, the invention relates to a combination therapy in which sonodynamic treatment of deeply-sited tumours with microbubble-sonosensitiser complexes is combined with treatment using immune checkpoint inhibitors. It further relates to methods of sonodynamic therapy in which a sonodynamic-induced abscopal response modulates a systemic regression of metastatic disease. In such methods the abscopal response may be further enhanced by co-administration of an immune checkpoint inhibitor. The invention is particularly suitable for the treatment of pancreatic cancer (e.g. pancreatic ductal adenocarcinoma) and associated metastasis.
THERAPY