Recruiting
Phase 1
Phase 2

Base-Edited Stem Cells

Sponsor:

National Institute of Allergy and Infectious Diseases (NIAID)

Code:

NCT06325709

Conditions

Chronic Granulomatous Disease (CGD)

X-Linked Chronic Granulomatous Disease

Eligibility Criteria

Sex: Male

Age: 18 - 70+

Healthy Volunteers: Not accepted

Interventions

Campath

Sirolimus

Base-edited hematopoietic stem and progenitor cells

Busulfan

Palifermin

Study Details

Brief summary:

Background:

Chronic granulomatous disease (CGD) is a rare immune disorder caused by a mutation in the CYBB gene. People with CGD have white blood cells that do not work properly and are at greater risk of getting infections. Researchers want to know if gene therapy using the patient's own base-edited stem cells can improve the white cells' functioning and result in fewer CGD-related infections.

Objective:

To learn if base-edited stem cells will correct the white blood cells in people with CGD.

Eligibility:

Males aged 18 years and older with X-linked CGD.

Design:

This is a non-randomized study. Participants with the specific mutation under study will be screened during the initial phase.

During the development phase, participants will undergo apheresis to collect stem cells for base-editing correction of the mutation.

During the treatment phase, participants will first receive Campath (alemtuzumab) to reduce the risk of an immune response to the new protein expressed by the base-edited cells. This will be followed by conditioning chemotherapy with busulfan and subsequent infusion of the base-edited stem cells. Participants will be maintained on sirolimus to further reduce the risk of an immune response to the new protein expressed by the base-edited cells.

Follow-up visits will continue for 15 years.

Conditions

Chronic Granulomatous Disease (CGD)

X-Linked Chronic Granulomatous Disease

Study ID

NCT06325709

Start date

Apr 17, 2024

Status verified date

Jul 29, 2026

Completion date

Dec 31, 2032

Anticipated

Primary completion date

Dec 31, 2032

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Male

Age: 18 - 70+

Healthy Volunteers: Not accepted

  • INCLUSION CRITERIA:

->= 18 years of age.
  • Confirmed CYBB c.676 C>T mutation.
  • Male patients.
  • Clinically stable and eligible to undergo apheresis and conditioning chemotherapy.

->=5 x 10\^6 cryopreserved cells/kg body weight available for study product manufacturing.
  • History of at least one prior serious infection or inflammatory complication requiring hospitalization despite conventional therapy.
  • In the experience of a qualified clinical investigator, the patient has a poor prognosis.
  • Able and willing to use a highly effective method of contraception, AND partner has communicated her willingness through subject to do same, if engaging in potentially reproductive sex from the signing of the informed consent and for 6 months after IMP infusion. Acceptable methods of contraception include the following:

  • Hormonal contraception in continuously effective use by female partner.
  • Male or female condom with spermicide as indicated.
  • Diaphragm or cervical cap in consistent and effective pattern of use with a spermicide by female partner.
  • Intrauterine device in-situ throughout above period by female partner.

EXCLUSION CRITERIA:

Individuals meeting any of the following criteria will be excluded from study participation:

  • Untreated, acute infection.
  • Elevated anti-gp91 specific autoantibodies >2 x ULN
  • Elevated anti-gp91 specific T cells (>10 fold)
  • Anti-platelet antibody screening with >1 anti-platelet antibody positive in the presence of an ongoing brain infection; OR >1 anti-platelet antibody positive and considered unsafe for study participation after consultation with hematology specialist.
  • Known hypersensitivity to busulfan or any component of the product.
  • Contraindications for administration of busulfan.
  • Any current or pre-existing hematologic malignancy.
  • Chronic infections that are considered unsafe for participation in the study by Infectious Disease Consultant.
  • Cardiac abnormalities and neurological abnormalities that are deemed unsafe to participate in the study.
  • Childhood malignancy (occurring before 18 years of age) in the patient or a first degree relative, or previously diagnosed known genotype of the participant conferring a predisposition to cancer (no DNA or other testing for cancer predisposition genes will be performed as part of the screen for this protocol).
  • Hematological parameters unsafe for apheresis or above Grade 2 Common Terminology Criteria for Adverse Events (CTCAE) criteria until improved.
  • Hepatic dysfunction- alanine aminotransferase (ALT >3.0 - 5.0 x upper limit of normal \[ULN\]), aspartate aminotransferase (AST >3.0 - 5.0 x ULN), bilirubin (>1.5 - 3.0 x ULN).
  • Renal dysfunction-serum creatinine >1.5 - 3.0 x ULN or creatinine clearance 59-30 mL/min/1.73 m\^2.
  • Coagulation dysfunction- Prothrombin INR or Partial thromboplastin time >2 x ULN (patients on controlled anticoagulation agents will not be excluded for therapeutic levels).
  • Uncontrolled hypertension- Systolic BP 140-159 mm Hg or diastolic BP 90-99 mm Hg.
  • Abnormal blood chemistries- Hyperkalemia (K >5.5 - 6.0 mmol/L), Hypokalemia (<LLN - 3.0 mmol/L and requiring intervention); OR Hypercalcemia (corrected serum calcium >11.5 - 12.5 mg/dL), Hypocalcemia (corrected serum calcium <8.0 -7.0 mg/dL)

These values exclude false abnormalities secondary to hemolysis.

  • Cytogenetic abnormalities evidenced on bone marrow aspirate.
  • Pulmonary dysfunction FEV1<25% predicted.
  • Previous treatment with gene therapy or gene editing products.
  • Previous receipt of non-HLA matched donor granulocyte transfusions.
  • Any other condition that, in the opinion of the investigator, may unduly compromise the safety or compliance of the patient, or would make successful study completion highly unlikely.
  • Unwilling to submit their information as part of the alemtuzumab (Campath(R)) Distribution Program application or the Distribution Program committee has determined the participant is not qualified to receive alemtuzumab.

NOTE: Alemtuzumab (campath) is no longer distributed commercially. To receive product, the physician must contact the program for the participant. If the participant is not willing to consent to submit their info (demographics, contact information, and rationale for use) to the program such that we can obtain the drug, then we cannot proceed with conditioning; therefore, no gene therapy will occur on this protocol.

Study Design

Enrollment

15 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Single Arm Study

Interventions

Campath

Immunomodulating agent: Daily subcutaneous administration beginning Day -9 for 5 days to reduce the risk of an immune response to the protein expressed by the BE HSPCs.

Sirolimus

Immunomodulating agent: Daily oral dosing beginning Day -1 for approximately 3 to 6 months to reduce the risk of an immune response to the protein expressed by the BE HSPCs.

Base-edited hematopoietic stem and progenitor cells

Investigational/Study Agent: Base-edited autologous CD34 plus hematopoietic stem and progenitor cell product. The product is administered intravenously as a single infusion. This product is under an IND.

Busulfan

Transplant Conditioning Agent: An alkylating chemotherapy drug to enhance engraftment of the study agent (base-edited stem cells). Conditioning will be given intravenously over 3 days with an approximate total dose of 12mg/kg. Drug levels obtained will be obtained to achieve the targeted total busulfan AUC of 65,000 ng/mL x hr.

Palifermin

Mucositis Prophylaxis Agent: Intravenous infusion of keratinocyte growth factor (Palifermin) at 60 mcg/kg/day before (Days -7 to Day -5 administration of busulfan and (Days 1 to 3) post-busulfan administration to prevent oral mucositis.

Filgrastim

Stem Cell Mobilizing Agent: Subcutaneous administration for 6 consecutive days. It is necessary to mobilize stem cells for collection.

Plerixafor

Stem Cell Mobilizing Agent: Subcutaneous administration for 2 consecutive days to improve stem cell collection.

Primary outcome measure

  • To evaluate the safety of base-edited autologous CD34+ cells [ Time Frame: Initiated from the time of the infusion of base-edited cells through 2 years post-infusion ]
  • To evaluate the efficacy of base-edited autologous CD34+ cells [ Time Frame: Assessed 12 months post-infusion of base-edited cells ]

Central Contacts and Locations

Central contacts

Locations

National Institutes of Health Clinical Center

Recruiting

Bethesda, Maryland, United States, 20892

Contacts

NIH Clinical Center Office of Patient Recruitment (OPR)

800-411-1222ccopr@nih.gov

More Information

Sponsor

National Institute of Allergy and Infectious Diseases (NIAID)

Last update posted

Aug 13, 2026

Last verified

Jul 29, 2026

Keywords

  • base editing
  • Gene Editing

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by National Institute of Allergy and Infectious Diseases (NIAID) on 2026-08-13.