The present invention relates to the use of benzimidazole derivatives for modulating, in particular inhibiting, the activity or function of the phosphoinositide 3'OH kinase family (hereinafter referred to as PI3 kinases), suitably PI3Kα, PI3Kδ, PI3Kβ and / or PI3K gamma. Suitably, the present invention relates to the use of benzimidazole compounds in the treatment of one or more disease states selected from the group consisting of: autoimmune disease, inflammatory disease, cardiovascular disease, neurodegenerative disease, allergy, asthma , pancreatitis, multiorgan failure, renal disease, platelet aggregation, cancer, sperm motility, transplant rejection, graft rejection, and lung injury. More suitably, the present invention relates to PI3Kβ-selective benzimidazoles for the treatment of cancer.