Idelalisib

**Semantic type:** Pharmacologic Substance

**Definition:** An orally bioavailable, small molecule inhibitor of the delta isoform of the 110 kDa catalytic subunit of class I phosphoinositide-3 kinase (PI3K) with potential immunomodulating and antineoplastic activities. Idelalisib inhibits the production of the second messenger phosphatidylinositol-3,4,5-trisphosphate (PIP3), preventing the activation of the PI3K signaling pathway and inhibiting tumor cell proliferation, motility, and survival. Unlike other isoforms of PI3K, PI3K-delta is expressed primarily in hematopoietic lineages. The targeted inhibition of PI3K-delta is designed to preserve PI3K signaling in normal, non-neoplastic cells.

**Synonyms:** - 5-Fluoro-3-phenyl-2-((S)-1-(9H-purin-6-ylamino)-propyl)-3H- quinazolin-4-one - CAL 101 - CAL-101 - CAL101 - GS 1101 - GS-1101 - GS1101 - IDELALISIB - Phosphoinositide-3 Kinase Delta Inhibitor CAL-101 - Zydelig