The goal of this study is determine the safety and tolerability of orally taken probiotic (R-5780) in patients currently on a PD-1 Pathway Checkpoint Inhibitor (checkpoint protein on immune cells called T cells) with Solid Tumors.
At least 18 years of age to 80
Ability to provide written informed consent
Unresectable stage III or stage IV melanoma, basal cell carcinoma, or squamous cell carcinoma as per the American Joint Committee on Cancer 2017 Guidelines (8th Edition) regardless of BRAF mutation status and other solid tumors.
Refractory to anti-PD (checkpoint Protein on Immune Cells called T cells)-1/L1 therapy per RECIST v1.1 defined as subject who has disease progression after receiving at least two complete cycles of ICI (immune checkpoint inhibitors) therapy or disease progression 6 months from initiation of ICI (immune checkpoint inhibitors) therapy while still on active therapy.
Any serious medical condition or laboratory abnormality or psychiatric condition or any other significant or unstable concurrent medical illness (in the opinion of the Investigator) would preclude protocol adherence or would make the safety of the study drug difficult to assess
Treatment with systemic broad-spectrum antibiotics.
No active viral infections.
Coexisting severe chronic diseases other than cancer (autoimmunity, inflammatory diseases)