IPI-3063

IPI-3063 is a potent and highly selective small molecule inhibitor of the phosphoinositide-3-kinase delta (PI3Kδ) isoform, originally developed by Infinity Pharmaceuticals. It demonstrates a biochemical IC50 of 2.5 nM for the p110δ subunit, with at least 400-fold selectivity over other Class I PI3K isoforms (α, β, and γ). In cellular assays, its selectivity for p110δ increases to over 1,000-fold. IPI-3063 has been primarily utilized as a research tool to study immune cell function, where it effectively suppresses B cell survival, proliferation, and differentiation into plasmablasts. Given its high selectivity and favorable pharmacokinetic profile in preclinical models, it has been investigated for potential therapeutic applications in B cell malignancies and autoimmune diseases.