About Activated PI3K Delta Syndrome
PI3K-delta is an enzyme inside white blood cells that tells them when to grow and act. In APDS a change in the PIK3CD or PIK3R1 gene leaves it switched on too much. B cells, which make antibodies, stay immature, and T cells wear out, so the body fights infections poorly while lymph nodes, spleen and gut lining swell with immune cells that should not be there. The condition was first described in 2013, so many adults were diagnosed late.
In a study of 53 people, 98% had repeated sinus and lung infections, 60% had airway damage on chest scans, 75% had swollen lymph tissue, 49% had herpes family virus infections and 13% developed lymphoma.
Care has long relied on antibody (immunoglobulin) replacement, preventive antibiotics, sirolimus to calm swollen lymph tissue and, for some, a stem cell transplant. Joenja (leniolisib), a twice-daily pill from Pharming that calms the overactive enzyme, became the first targeted treatment on March 24, 2023 for people 12 and older. On September 11, 2026 the FDA extended it to children 4 to 11 who weigh at least 27 kg, with new 40 mg and 50 mg tablets. In its 12-week trial of 31 people, lymph nodes shrank and the share of naive B cells, a sign of a healthier immune system, rose about 37 percentage points against almost no change on placebo.
Common Symptoms of Activated PI3K Delta Syndrome
Recognizing the signs of Activated PI3K Delta Syndrome early can lead to faster diagnosis and better outcomes. Symptoms may vary in severity from person to person. If you or a loved one are experiencing any of the following, consider speaking with a specialist.
- Repeated sinus, ear and lung infections, starting in early childhood
- Lasting damage to the lung airways (bronchiectasis)
- Swollen lymph nodes, and an enlarged spleen or liver
- Infections with herpes family viruses
- Gut inflammation and low blood counts
- A higher risk of lymphoma, seen in 13% of 53 people in one study
Who Activated PI3K Delta Syndrome Affects
Infections usually begin in infancy or early childhood, but diagnosis often comes years later, a median delay of 7 years, and many people are first told they have common variable immunodeficiency (CVID). APDS is autosomal dominant: one changed copy of PIK3CD (APDS1) or PIK3R1 (APDS2) is enough to cause it, so a parent with APDS has a 50% chance of passing it to each child.
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FDA-Approved Treatments for Activated PI3K Delta Syndrome
There is currently 1 FDA-approved medication for Activated PI3K Delta Syndrome. These therapies represent the current standard of care and may be used alongside or compared against investigational treatments in active clinical trials.
Source: openFDA drug labeling data. This list may not include all treatments. Always consult your doctor.
Help Paying for Activated PI3K Delta Syndrome Treatment
Charity funds and drugmaker programs for Activated PI3K Delta Syndrome, checked at the source.
Side Effect Explorer
Real-world side effect reports from the FDA Adverse Event Reporting System (FAERS). Includes both FDA-approved drugs and investigational therapies from active clinical trials. Click any drug to see what patients reported.
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Genetic Testing
Genetic testing can confirm a diagnosis, guide treatment decisions, and identify family members who may be at risk.
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Trusted Activated PI3K Delta Syndrome Resources
Reputable organizations and medical references for learning more about Activated PI3K Delta Syndrome, including disease registries, foundation resources, and clinical guidelines.
- MedlinePlus Genetics - Activated PI3K-delta Syndrome
- Immune Deficiency Foundation - Activated PI3K Delta Syndrome (APDS)
- FDA - First treatment for children aged 4 to 11 with APDS (September 11, 2026)
- Coulter et al., Clinical spectrum and features of APDS, J Allergy Clin Immunol 2017
- Joenja prescribing information (DailyMed)