Prebiotic Food-enriched Diet (PreFED) to Enhance the Microbiome and Response to First-line Immunotherapy in Unresectable Melanoma

Primary Objectives • Evaluate the effect of dietary intervention on the abundance of Faecalibacterium in stool samples from baseline to 12 weeks Secondary Objectives * Determine the best overall response rate (BORR) to PreFED + ICB regimens and landmark ORR at 12 weeks (intervention) and 24 weeks (maintenance) * Determine progression-free survival (PFS) and overall survival (OS) with PreFED + ICB regimens * Compliance and adherence to the dietary intervention at 12 weeks and maintenance at 24 weeks * Determine the safety (diet-related AEs) and tolerability (GSRS-IBS) of the dietary intervention at 12 weeks and maintenance at 24 weeks * Assess the rate of immune related adverse events in patients on ICB regimens receiving dietary intervention at 12 weeks and maintenance at 24 weeks * Assess the effects of dietary intervention on systemic and tumor immunity * Assess the effect of dietary intervention on overall gut microbiome composition and networks at 12 weeks and maintenance at 24 weeks * Assess the effects of dietary intervention on gut metabolic output and systemic metabolism at 12 weeks and maintenance at 24 weeks * Assess the effects of dietary interventions on quality of life and other patient reported outcomes (PROs) at 12 weeks and maintenance at 24 weeks