ZYDELIG® mechanism of action

ZYDELIG is the first oral PI3K inhibitor approved in both relapsed/refractory follicular lymphoma and relapsed CLL

ZYDELIG inhibits PI3Kδ, a key driver of multiple B-cell processes

Inhibits multiple signaling pathways, including BCR, CXCR4, and CXCR52-4

Image of how ZYDELIG® (idelalisib) inhibits multiple signaling pathways, including BCR, CXCR4, and CXCR5.

Inhibits proliferation and induces apoptosis

Image of how ZYDELIG® (idelalisib) inhibits proliferation and induces apoptosis.

Inhibits homing and adhesion

Image of how ZYDELIG® (idelalisib) inhibits homing and adhesion.

Mobilizes malignant B cells to the periphery, and may reduce lymph node burden5

Image of how ZYDELIG® (idelalisib) mobilizes malignant B cells to the periphery and may reduce lymph node burden.

Effects were observed in cell lines derived from malignant B cells and in primary tumor cells.

Image showing the detailed PI3K delta pathway.

For illustrative purposes only. Not all components of the pathway are illustrated.

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ZYDELIG dosing

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Adverse event monitoring &

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BCR=B-cell receptor; CLL=chronic lymphocytic leukemia; CXCR=C-X-C chemokine receptor; PI3Kδ=phosphatidylinositol 3-kinase delta.


  1. ZYDELIG® (idelalisib) [prescribing information]. Foster City, CA: Gilead Sciences, Inc.; rev October 2018.
  2. Sharman JP, Coutré SE, Furman RR, et al. Efficacy of idelalisib in CLL subpopulations harboring del(17p) and other adverse prognostic factors: results from a phase 3, randomized, double-blind, placebo-controlled trial. Poster presented at: American Society of Clinical Oncology; May 30-June 3, 2014; Chicago, IL.
  3. Puri KD, Gold MR. Selective inhibitors of phosphoinositide 3-kinase delta: modulators of B-cell function with potential for treating autoimmune inflammatory diseases and B-cell malignancies. Front Immunol. 2012;3:256. doi:10.3389/fimmu.2012.00256
  4. Coutré SE, Barrientos JC, Brown JR, et al. Management of adverse events associated with idelalisib treatment: expert panel opinion. Leuk Lymphoma. 2015;56(10):2779-2786.
  5. Furman RR, Sharman JP, Coutré SE, et al. Idelalisib and rituximab in relapsed chronic lymphocytic leukemia. N Engl J Med. 2014;370(11):997-1007. doi:10.1056/NEJMoa1315226