Leniolisib treatment for immune system disorders

A Study to Assess Safety and Tolerability, and Explore Efficacy of Leniolisib for Immune Dysregulation in Primary Immunodeficiency Disorders

PHASE2 · Pharming Technologies B.V. · NCT06549114

This study is testing if a new medication called leniolisib is safe and helpful for people aged 12 to 75 with certain immune system disorders caused by genetic issues.

Quick facts

PhasePHASE2
Study typeInterventional
Enrollment12 (estimated)
Ages12 Years to 75 Years
SexAll
SponsorPharming Technologies B.V. (industry)
Drugs / interventionsRituximab, belimumab, alemtuzumab, ruxolitinib, methotrexate, cyclophosphamide, prednisone
Locations1 site (Bethesda, Maryland)
Trial IDNCT06549114 on ClinicalTrials.gov

What this trial studies

This exploratory, non-randomized, open-label study evaluates the safety and tolerability of leniolisib in patients aged 12-75 with genetically defined primary immunodeficiency disorders (PIDs) linked to PI3K signaling. Participants will receive escalating doses of leniolisib, starting at 10 mg twice daily, increasing to 30 mg and then 70 mg over a 20-week period. The study also aims to assess pharmacokinetics, pharmacodynamics, and clinical efficacy measures associated with the treatment. Follow-up visits will occur approximately 28 days after the last dose for those not continuing treatment.

Who should consider this trial

Good fit: Ideal candidates are individuals aged 12 to 75 diagnosed with specific genetic variants causing primary immunodeficiency disorders.

Not a fit: Patients with primary immunodeficiency disorders not linked to the specified genetic variants or those with juvenile myelomonocytic leukemia will not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could improve immune function and overall health in patients with specific primary immunodeficiency disorders.

How similar studies have performed: While this approach is exploratory, similar studies targeting immune dysregulation have shown promise, suggesting potential for success.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Subjects 12 to 75 years of age.
2. Diagnosed with a PID due to disease-causing pathogenic or likely pathogenic variant(s) in the following genes: SOCS1, PTEN, CTLA4, NFKB1 (only those variants leading to NFKB pathway activation), or FAS (germline or somatic), or diagnosed with RAS associated leukoproliferative disorder (and not juvenile myelomonocytic leukemia \[JMML\]) due to somatic variants in NRAS or KRAS.
3. Subjects must have 1 or more of the following:

   * One or more blood cytopenias related to the underlying PID defined as hemoglobin \<10 g/dL, platelet count \<100,000/µL, or neutrophil count \<1000/µL
   * Splenomegaly evident by CT imaging with craniocaudal spleen measurement \>10 cm
   * Lymphadenopathy evident by CT imaging with at least 1 measurable index lymph node (long axis \>1.5 cm) as per Cheson methodology
   * GLILD or other PID-related ILD with quantifiable CT chest imaging findings evident on baseline CT scan
4. At screening, vital signs.

   * Systolic blood pressure 80-139 mm Hg
   * Diastolic blood pressure 50-89 mm Hg
   * Pulse rate 50-110 bpm
   * Oxygen saturation 93-100%
5. Subjects or their legal representatives (for subjects under the age of 18 years) must be able to provide written informed consent.

Exclusion Criteria:

1. Subject has had a successful hematopoietic stem-cell transplant (HSCT).
2. Previous or concurrent use of immunosuppressive medication, such as:

   * Use of an mTOR inhibitor or a PI3Kδ inhibitor within 3 weeks prior to first dosing .
   * Rituximab or other B-cell depleting antibodies, belimumab, cyclophosphamide, or alemtuzumab within 6 months prior to first dosing.
   * Cyclosporine A, mycophenolate mofetil, 6-mercaptopurine, azathioprine, methotrexate, tacrolimus, ruxolitinib, or other JAK inhibitors within 3 weeks prior to first dosing.
   * Corticosteroids above 25 mg prednisone or equivalent per day within 2 weeks prior to first dosing.
   * Other immunosuppressive agents expected to have a significant impact on immune cell number or function.
   * Abatacept is allowed during study if the subject has been receiving a stable dosing regimen for more than 3 months prior to first dosing.
3. Subject is receiving concurrent treatment with another investigational therapy or use of another investigational therapy less than 4 weeks or 5 half-lives (whichever is longer) prior to first dosing.
4. History of hypersensitivity to the study drug or to drugs of similar chemical classes.
5. Current use of medication known to be a strong inhibitor, or moderate or strong inducer, of isoenzyme P450 CYP3A.
6. Current use of medications that act as BCRP, OATP1B1, and OATP1B3 substrates.
7. Subject has a history or current electrocardiogram (ECG) abnormalities indicating a significant risk of safety for subjects participating in the study
8. History of acquired immunodeficiency diseases, including a positive HIV test result at screening.
9. Uncontrolled chronic or recurrent infectious disease (except those considered to be characteristic of a PID) or evidence of tuberculosis infection
10. Any surgical or medical condition which may jeopardize the subject in case of participation in the study, or might significantly alter the absorption, distribution, metabolism, or excretion of drugs.
11. A positive hepatitis B surface antigen, positive hepatitis B PCR, positive hepatitis C PCR, or positive hepatitis C antibody result at screening.
12. Administration of live vaccines starting from 6 weeks before first dose of study medication.
13. Subject has a previous diagnosis of lymphoma within 1 year of the first dose of study medication.
14. Subject has a history of malignancy (except lymphoma) within 3 years before the first dose of study medication, except for adequately treated cancers of the skin (basal or squamous cell) or carcinoma in situ of the uterine cervix.
15. Subject has uncontrolled post-transplant lymphoproliferative disease (PTLD)-like EBV related lymphoproliferative disease.
16. Donation or loss of 400 mL or more of blood within 8 weeks before the first dose.
17. Subject has had major surgery requiring hospitalization or radiotherapy within 4 weeks prior to the first dose or has a planned or expected major surgical procedure during the study period.
18. Pregnant or nursing (lactating) individuals,.
19. Individuals of child-bearing potential, unless they are using highly effective methods of contraception.

Where this trial is running

Bethesda, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Primary Immunodeficiency Disorders

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.