Idelalisib
Zydelig (idelalisib) is a prescription medication classified as a phosphoinositide 3-kinase (PI3K) inhibitor used to treat certain blood cancers. It is primarily prescribed for adults with relapsed chronic lymphocytic leukemia (CLL), relapsed follicular lymphoma (FL), and relapsed small lymphocytic lymphoma (SLL) who have received at least two prior systemic therapies. The medication works by targeting and inhibiting the PI3K delta pathway, which is involved in the growth and survival of cancer cells.
Zydelig is a targeted cancer therapy used to treat relapsed blood cancers including CLL, FL, and SLL.
Key facts at a glance
- RxNorm
- 1544466
- Generic
- Zydelig
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Zydelig is indicated for the treatment of adults with relapsed chronic lymphocytic leukemia (CLL) in combination with rituximab, relapsed follicular lymphoma (FL) after at least two prior systemic therapies, and relapsed small lymphocytic lymphoma (SLL) after at least two prior systemic therapies.
Zydelig is a PI3K delta inhibitor that works by blocking the PI3K signaling pathway, which plays a key role in the proliferation, survival, and migration of malignant B-cells. By inhibiting this pathway, it promotes programmed cell death (apoptosis) and inhibits the growth of cancer cells.
Zydelig carries FDA boxed warnings for hepatotoxicity (liver injury) and diarrhea/colitis. Common side effects include diarrhea, nausea, abdominal pain, fatigue, and rash. Serious adverse reactions may include pneumonitis, infections, and intestinal perforation. Regular monitoring of liver function and blood counts is required during treatment. The medication should not be used in patients with serious hepatic impairment.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 27, 2026. · Read our editorial policy