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Therapeutic Use of Tadekinig Alfa in NLRC4 Mutation and XIAP Deficiency

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT03113760
Recruitment Status : Active, not recruiting
First Posted : April 14, 2017
Last Update Posted : March 10, 2023
Information provided by (Responsible Party):
AB2 Bio Ltd.

Brief Summary:
This is a Phase 3 study to assess the safety and efficacy of Tadekinig alfa in patients with monogenic, interleukin-18 (IL 18) driven autoinflammation due to Nucleotide-binding oligomerization domain, leucine-rich repeat and caspase recruiting domain (CARD domain) containing 4 (NLRC4) - Macrophage activation syndrome (MAS) mutation (NLRC4-MAS mutation) or X-linked inhibitor of apoptosis (XIAP) deficiency. Because of the likelihood for pathogenic IL-18 in certain monogenic diseases, patients known to harbor deleterious mutations in NLRC4-MAS or XIAP and who have a history of ongoing inflammation will be enrolled if they have ferritin ≥ 500 ng/mL or persistent C reactive protein (CRP) elevation ≥ 2 times the upper limit of normal (ULN) and the patients should have a Modified Autoinflammatory Disease Activity Index (mAIDAI) ≥ 4.

Condition or disease Intervention/treatment Phase
NLRC4-MAS XIAP Deficiency Drug: Tadekinig alfa Other: 0.9% sodium chloride Phase 3

Detailed Description:
The study is designed with single-arm, open-label phase (SAOL) of Tadekinig alfa treatment duration for 18-week followed by an up to 16-week Randomized Withdrawal (RW) period for efficacy and safety evaluation, with no interruption between the two phases of treatment. The screening period will occur before the SAOL phase and before the first dose of Investigational Medicinal Product (IMP)

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 15 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Initial phase of 18 weeks is a single arm, open-label (SAOL) period where Tadekinig alfa is administered in addition to the standard of care treatment used for the control of flares. The SAOL period will be followed by an up to 16-week randomized withdrawal phase (RW). All patients who showed response to treatment at the end of the SAOL phase will be enrolled in the RW phase. In the RW phase patients will be randomized to either Tadekinig alfa or placebo.
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Multicenter, Double-blind, Placebo-controlled, Randomized Withdrawal Trial With Tadekinig Alfa (r-hIL-18BP) in Patients With IL-18 Driven Monogenic Autoinflammatory Conditions: NLRC4 Mutation and XIAP Deficiency
Actual Study Start Date : July 21, 2017
Estimated Primary Completion Date : May 30, 2023
Estimated Study Completion Date : July 30, 2023

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Tadekinig alfa
Patients that showed response to treatment in the SAOL phase will receive Tadekinig alfa for up to 16 weeks.
Drug: Tadekinig alfa
Tadekinig alfa is a soluble glycoprotein of 164 amino acids produced from Chinese Hamster Ovary cell line. Tadekinig alfa is supplied as a colorless to slightly yellow, sterile solution for injection in glass vials containing sodium chloride, and 0.02M sodium phosphate buffer as excipients. It is available in a concentration of 20mg/0.5mL.
Other Names:
  • IL-18BP
  • r-hIL-18BP

Placebo Comparator: 0.9% sodium chloride
Patients that showed response to treatment in the SAOL phase will receive placebo comparator for up to 16 weeks.
Other: 0.9% sodium chloride
To ensure that the treatment remains blinded for the entire study period, the placebo solutions will be supplied in identical vials and similar labelling as the active drug and will be indistinguishable in terms of their texture, color, and smell.

Primary Outcome Measures :
  1. Prevention of flares [ Time Frame: 16 weeks ]

    The primary outcome measure is the time to first occurrence of disease reactivation during the 16-week RW phase.

    Method of assessment : Biomarkers (CRP / Ferritin) and clinical manifestations of systemic inflammation and end-organ damage.

Secondary Outcome Measures :
  1. Best response [ Time Frame: 18 weeks ]
    Best response to therapy during the SAOL phase including either complete response, partial response or disease improvement Method of assessment : Biomarkers (CRP / Ferritin) and clinical manifestations of systemic inflammation and end-organ damage.

  2. Duration of response [ Time Frame: 18 weeks ]
    Duration of response to therapy during the SAOL phase

  3. Intensity of flares [ Time Frame: 16 weeks ]
    Intensity of flares (defined by the level of activity given by the mAIDAI)

  4. Serum CRP, Serum Ferritin [ Time Frame: 34 weeks ]
    Laboratory measure ug/mL for CRP, and ng/mL for Ferritin

  5. Improvement of fevers, improvement of hepato/splenomegaly [ Time Frame: 34 weeks ]
    Clinical assessments if present at Baseline

  6. Improvement in serum albumin and liver transaminases, anemia and/or platelet count [ Time Frame: 34 weeks ]
    Laboratory measures if present at Baseline

  7. Hospital length of stay [ Time Frame: 34 weeks ]
    Length of hospitalisation

  8. Change in Physician Global Assessment (PGA) [ Time Frame: 34 weeks ]
    Change from RW baseline to EOS in the PGA symptom severity score

  9. Quality of life [ Time Frame: 34 weeks ]
    Change of patient's/Caregiver's qualitative evaluation of health status during the study duration

  10. Presence of skin rash - evolution if present at Baseline or appearance during the study [ Time Frame: 34 weeks ]
    Measured by the local tolerability index

  11. Tolerance to oral/enteral nutrition for hospitalized patients if intestinal dysfunction was present at Baseline [ Time Frame: 34 weeks ]
    Measured by the kcal per day

  12. Improvement of stool output for hospitalized patients if intestinal dysfunction was present at Baseline [ Time Frame: 34 weeks ]
    mL per 24hours

  13. Adverse events will be reported [ Time Frame: 34 weeks (SAOL + RW phases) ]
    Including AESI (Adverse Events of Special Interest)

  14. Physical examination findings and vital signs [ Time Frame: 34 weeks (SAOL + RW phases) ]
    Clinically significant changes from Baseline

  15. Laboratory assessments [ Time Frame: 34 weeks (SAOL + RW phases) ]
    Including clinically significant changes from Baseline in hematology with platelet counts, CRP, ESR, ferritin, fibrinogen, D-dimer, liver enzymes. (Followed until resolution)

  16. Immunogenicity evaluation [ Time Frame: 34 weeks (SAOL + RW phases) ]
    Generation of anti-recombinant human IL-18BP (anti-rhIL-18BP) antibodies

  17. Local tolerability at the injection site [ Time Frame: 34 weeks (SAOL + RW phases) ]
    Evaluated by a standardized assessment

  18. Disease reactivation rate [ Time Frame: 18 weeks ]
    Disease reactivation rate for individual subjects (number of disease reactivations experienced per week while each subject is on the study treatment during the SAOL phase)

  19. Treatment failures [ Time Frame: 34 weeks ]
    Treatment failures (i.e. patients who experience at least one disease reactivation)

Other Outcome Measures:
  1. Response to therapy [ Time Frame: 18 weeks ]
    Response to therapy in the SAOL phase from Week 10 onwards

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No


  1. Patients with genetic diagnosis of NLRC4-MAS mutation or XIAP deficiency (caused by BIRC4 gene mutation) as confirmed by analysis performed at the central genetics laboratory. If possible, flow cytometry assay will be performed in parallel to confirm diagnosis of XIAP deficiency. (Note: Previous flow cytometry assay results will be permitted for confirmation of XIAP deficiency diagnosis.)
  2. Patients with XIAP deficiency and a previous bone marrow transplantation are allowed, if they show evidence of primary or secondary graft failure, or failure to achieve phenotypic correction with evidence of XIAP-related disease recurrence or clinically significant mixed chimerism.
  3. Ferritin ≥ 500 ng/mL or persistent elevation of CRP ≥ 2x ULN and mAIDAI ≥4
  4. Patients receiving corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) or disease modifying anti-rheumatic drugs (DMARDs), and/or IL-1 blockade with insufficient response to treatment upon enrollment are allowed into the study. Patients not receiving any of these treatments before start of therapy are also allowed.
  5. Women of childbearing potential with negative urine pregnancy test (UPT) at all visits (if UPT is positive, a blood test for human chorionic gonadotropin (hCG) to be performed) and who agree to follow highly effective birth control recommendations during the study and until 1 month after the end of the treatment. Birth control methods considered highly effective are: combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation, progestogen-only hormonal contraception associated with inhibition of ovulation, intrauterine device (IUD), intrauterine hormone-releasing system (IUS), bilateral tubal occlusion, vasectomized partner or sexual abstinence. In each case of delayed menstrual period (over one month between menstruations, confirmation of absence of pregnancy is strongly recommended. This recommendation also applies to women of childbearing potential with infrequent or irregular menstrual cycles. A post-study contraception duration of 4 weeks is recommended taking into account the median half-life of Tadekinig alfa of almost 40h and 5 half-lives representing a duration of 200 hours.


  1. Patients with life-threatening co-morbidities not associated with the underlying NLRC4-mutation or XIAP deficiency
  2. Positive test for or prior history of HIV, Hepatitis B or Hepatitis C (serology)
  3. Presence of active infections or a history of pulmonary TB infection with or without documented adequate therapy
  4. Presence of life threatening infections
  5. Oncologic causes of symptoms; current or previous history of malignancy
  6. Presence of CNS manifestations (i.e. seizures, altered mental status, signs of increased intracranial pressure, chronic papilledema, loss of vision, other sensorineural deficiencies, etc.)
  7. Patients suffering from biallelic mutations in any of the following genes: PRF1/Perforin, UNC13D/Munc 13-4, STX11/Syntaxin11, STXB2/Munc 18-2, RAB27A/Rab27a (Griscelli syndrome type 2), LYST (Chediak-Higashi syndrome), AP3B1, ADTB3A, HPS2 mutations (Hermansky-Pudlak syndrome 2) and X-linked lymphoproliferative syndrome (XLP)-1 with SH2D1A mutation
  8. Patients who are pregnant or nursing, women of childbearing potential who are unwilling to use highly effective birth control methods (see definition in Inclusion Criteria above) through 4 weeks after the end of their participation in the study
  9. Concomitant use of immunosuppression therapies excluded by the protocol. Note: NSAIDs, glucocorticoids, cyclosporine, tacrolimus, and IL-1 inhibitors (anakinra, canakinumab, or rilonacept, or others) are allowed
  10. Patients and/or parents (or legal representative, if applicable) not willing to sign assent/informed consent
  11. Hypersensitivity to the active substance or one of the excipients of the investigational product

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03113760

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United States, California
UCSD _ Department of Pediatrics / Rady Children's Hospital
La Jolla, California, United States, 92056
United States, Georgia
Children's Healthcare of Atlanta at Egleston
Atlanta, Georgia, United States, 30322
United States, Massachusetts
Boston Children's Hospital
Boston, Massachusetts, United States, 02115
United States, Ohio
Cincinnati Children's Hospital Medical Center
Cincinnati, Ohio, United States, 45229
United States, Pennsylvania
Children Hospital of Philadelphia
Philadelphia, Pennsylvania, United States, 19104
United States, Texas
Texas Children's Hospital _ Baylor College of Medicine
Houston, Texas, United States, 77030
Canada, Ontario
The Hospital for Sick Children
Toronto, Ontario, Canada, ON M5G 1X8
Canada, Providence
CHU Sainte-Justine
Montréal, Providence, Canada, QC H3T 1C5
Universitätsklinikum Freiburg, Centrum für Chronische Immundefizienz (CCI) - Paediatric Unit
Freiburg, Baden-Württemberg, Germany, 79106
Sponsors and Collaborators
AB2 Bio Ltd.
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Principal Investigator: Ed M Behrens, MD Children Hospital of Philadelphia
Additional Information:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: AB2 Bio Ltd.
ClinicalTrials.gov Identifier: NCT03113760    
Other Study ID Numbers: NLRC4/XIAP.2016.001
First Posted: April 14, 2017    Key Record Dates
Last Update Posted: March 10, 2023
Last Verified: July 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided
Plan Description: This information will be provided soon

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
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Lymphoproliferative Disorders
Genetic Diseases, X-Linked
Lymphatic Diseases
Immunoproliferative Disorders
Immune System Diseases
Genetic Diseases, Inborn