Clinical Trial Finder

Inclusion Criteria:

• - Age ≥18 years old.

• - English-speaking.

• - Body mass index (BMI) 18.5-45 kg/m2.

• - ECOG performance status of 0 or 1.

• - Histologically confirmed stage III/IV, unresectable cutaneous or mucosal melanoma.

Asymptomatic brain metastases are allowed.

• - Planned initiation of 1st line standard-of-care approved immune checkpoint blockade (anti-PD1 +/- anti-CTLA4 or anti-LAG3 inhibitors) in the metastatic setting (prior ICB in adjuvant setting is allowed if last exposure ≥ 6 months prior).

Prior targeted therapy is also allowed.

• - Returning to MD Anderson for restaging and follow-up (ICB treatment may occur locally) - WOCP must have negative UPT within 1 week of beginning dietary intervention.

• - Self-reported willingness to eat the provided foods (with some tailoring to their food preferences) - Self-reported willingness to comply with scheduled visits, undergo venipuncture, provide stool samples.

Exclusion Criteria:

• - Uveal melanoma previous ICB treatment in the metastatic setting.

• - History of inflammatory bowel disease, total colectomy, or bariatric surgery.

• - Currently taking steroids > Prednisone 10 mg/day or equivalent.

• - Medical contraindications to the Intervention Diet as determined by the treating physician.

• - Self-reported major dietary restrictions, including but not limited to relevant food allergies, celiac disease, or diets such as vegan, ketogenic, extended fasting.

• - Insulin-dependent diabetes or condition requiring bile acid sequestrants.

• - Unable or unwilling to undergo study procedures.

• - IV antibiotic use in the past month or oral antibiotic use in past 2 weeks.

• - Regularly taking supplements containing prebiotics, fiber and/or probiotics, and unable/unwilling to discontinue for the purpose of the study.

• - Current smoker or heavy drinker (defined as >14 drinks per week) or current illicit drug use.

• - Currently pregnant, planning to become pregnant, or lactating.

• - Concurrent malignancy requiring systemic therapy other than hormonal therapy.

- Cognitively impaired adults

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

Arms

Experimental: Prebiotic food-enriched diet (PreFED)

Participants found to be eligible to take part in this study, the participant will be provided with PreFED snacks during the 12-week PreFED Intervention Phase. The MD Anderson Bionutrition Research Core's (BRC) kitchen (led by the study co-chair) will provide 2-3 fully prepared snacks for each day of the intervention phase as part of the bi-weekly snack packout. The snacks will be shipped to the participant, or the participant may pick them up in person.

Interventions

Dietary Supplement: - Prebiotic food-enriched diet (PreFED)

Given by PO