Leniolisib
Leniolisib is a selective PI3K-delta inhibitor used to treat Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS), a rare primary immunodeficiency caused by genetic mutations affecting immune cell function. It works by blocking the active binding site of the PI3K-delta enzyme, which is critical for B-cell development and immune cell signaling, thereby reducing abnormal immune cell proliferation and improving immune function in affected patients.
Leniolisib is a targeted PI3K-delta inhibitor approved for treating APDS, a rare genetic immunodeficiency disorder, by selectively blocking the PI3K-delta enzyme to regulate abnormal immune cell growth.
Key facts at a glance
- ATC
- L03AX22
- RxNorm
- 2633005
- Generic
- Leniolisib
- Class
- atc-l03
- Brands
- Joenja
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- 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.
Leniolisib is indicated for the treatment of Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS) in adult and pediatric patients aged 12 years and older. APDS is a rare primary immunodeficiency caused by gain-of-function mutations in the PIK3CD or PIK3R1 genes, leading to dysregulated PI3K-delta signaling, abnormal B-cell and T-cell function, and increased susceptibility to infections and lymphoid hyperplasia.
Leniolisib is a selective PI3K-delta inhibitor that binds to the active site of the PI3K-delta enzyme, blocking its catalytic activity. PI3K-delta is critical for signaling pathways that regulate B-cell development, activation, proliferation, and survival. By inhibiting this enzyme, leniolisib reduces hyperactive signaling, decreases abnormal lymphoid proliferation, and helps normalize immune function in patients with APDS. The drug demonstrates high selectivity for PI3K-delta over other PI3K isoforms (28-fold over PI3K-alpha, 43-fold over PI3K-beta, and 257-fold over PI3K-gamma), minimizing off-target effects.
Leniolisib is an oral medication typically taken twice daily. Clinical trials showed improvement in immune parameters and reduction in lymph node and tonsil size. Common adverse reactions include headache, sinusitis, and diarrhea. As an immunomodulatory agent, patients should be monitored for infections during treatment. Safety and effectiveness in pediatric patients under 12 years of age have not been established. Always consult current prescribing information for complete safety details and contraindications.
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 July 26, 2026. · Read our editorial policy