Described herein are methods and compositions for treating
cancer and for predicting a subjects' response to combination checkpoint inhibitor therapy. Aspects of the disclosure relate to a method of treating
cancer and / or reducing
toxicity to a therapy in a subject comprising administering to the subject a composition comprising at least one isolated or purified
population of
bacteria belonging to one or more of the genera Flavonifractor, Dielma,
Akkermansia, Alistipes,
Bacteroides, Butyricimonas, Vampirovibrio, Tyzzerella, Parabacteroides distasonis, Fournierella, Fournierella massiliensis, Eisenbergiella tayi, Tissierellales, Hungateiclostridium thermocellum, Dorea formicigenerans, Caloramator coolhaasi, Muricomes, Geosporobacter,
Prevotella paludivivens,
Lactobacillus secaliphilus,
Bacteroides finegoldii,
Lactobacillus johnsonii, Parapedobacter composti, and Anaerotignum lactatifermentans and wherein the method further comprises treating the subject with a combination of (i) a PD-1, PDL1, or PDL2 inhibitor and (ii) a CTLA-4, B7-1, CN or B7-2 inhibitor.