Sonolisib (PX-866), an improved Wortmannin analogue, is an oral, irreversible, and pan-isoform inhibitor of PI3K (IC50=0.1 nM (p110α), 1.0 nM (p120γ), 2.9 nM (p110δ)). Antitumor activity[2].IC50 & Target: IC50: 0.1 nM (p110α), 1.0 nM (p120γ), 2.3 nM (p110δ)[2]In Vitro: Sonolisib (PX-866) inhibits the production of the secondary messenger phosphatidylinositol-3,4,5-trisphosphate (PIP3) and activation of the PI3K/Akt signaling pathway, which may result in inhibition of tumor cell growth and survival in susceptible tumor cell populations.