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JSP191 Antibody Targeting Conditioning in SCID Patients

Phase 1
Active, not recruiting
Conditions
SCID
Interventions
Biological: Humanized anti-CD117 Monoclonal Antibody (JSP191)
Registration Number
NCT02963064
Lead Sponsor
Jasper Therapeutics, Inc.
Brief Summary

A Phase 1/2 study to evaluate the safety, tolerability, and efficacy of an antibody conditioning regimen, known as JSP191, in patients with Severe Combined Immune Deficiency undergoing blood stem cell transplantation

Detailed Description

A Phase 1/2 study to evaluate the safety, tolerability, and efficacy of an antibody conditioning regimen, known as JSP191, in patients with SCID undergoing blood stem cell transplantation. Blood Stem Cell transplantation offers the only potentially curative therapy for SCID.

The biological conditioning regimen, JSP191, is an antibody that binds to CD117. CD117 is the receptor for Stem Cell Factor on blood forming cells. CD117 binding to Stem Cell Factor is critical for survival and maintenance of blood forming stem cells. The binding of JSP191 to CD117 blocks CD117 from binding to Stem Cell Factor on blood forming stem cells. In the absence of CD117/Stem Cell Factor binding, hematopoietic stem cells that are currently occupying the bone marrow niches in SCID patients exit from the bone marrow.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
40
Inclusion Criteria
  1. Typical SCID as defined by Primary Immune Deficiency Treatment Consortia including but not limited to the following subtypes:

    1. T-, B+, NK-: IL-2Rcγ deficient, JAK3-deficient (no longer enrolling)
    2. T-, B-, NK+: RAG1/2 deficient, Artemis-deficient
    3. T-, B+, NK+: IL7Rα deficient, CD3 subunit deficient, CD45 deficient (no longer enrolling) OR Variant SCID with absent or low T cell function, Omenn syndrome, Leaky SCID, Reticular dysgenesis, Adenosine deaminase deficiency, and Purine nucleoside phosphorylase deficiency may be included after consultation with the medical monitor.
  2. Patients with human leukocyte antigen (HLA) matched related or unrelated donors

  3. Adequate end organ function as defined in study protocol

  4. Age ≤ 12 years

  5. Prior donor of appropriate age (≥ 5 years old) available for re-collection of stem cells

  6. Previous allogeneic Hematopoietic Cell Transplantation HCT (≥ 6 months post initial transplant) with poor graft function

Key

Exclusion Criteria
  1. Patients with any acute or uncontrolled infections
  2. Patients receiving any other investigational agents, or concurrent biological, chemotherapy, or radiation therapy
  3. Patients with active malignancies
  4. Active GVHD within 6 months prior to enrollment, or on immunosuppressive therapy for GVHD

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Blood Stem Cell Transplant w/ anti-CD117 conditioningHumanized anti-CD117 Monoclonal Antibody (JSP191)The study will enroll two groups: Group A: previously transplanted SCID patients; Group B: newly diagnosed SCID. The study plans to assess JSP191 in different dose cohorts. Patients will receive a single dose of intravenous JSP191 antibody followed by monitoring for antibody clearance. Once the antibody has cleared below a certain level, patients will receive stem cell transplant and be monitored for hematopoietic recovery.
Primary Outcome Measures
NameTimeMethod
Phase 1: Safety and tolerability of JSP191 as conditioning therapy in SCID patients undergoing HCT: adverse eventsUp to 5 years post Donor Cell Transplant (28 days dose limiting toxicity period)

The number of subjects experiencing dose limiting toxicities including adverse events and serious adverse events will be assessed.

Phase 2: Efficacy of JSP191 as conditioning therapy in SCID patientsWeeks 36-104 post Donor Cell Transplant

To enable immune reconstitution, as determined by the production of naive T cells

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (11)

Children's Hospital of Los Angeles

🇺🇸

Los Angeles, California, United States

UCLA Mattel Children's Hospital

🇺🇸

Los Angeles, California, United States

Lucile Packard Children's Hospital

🇺🇸

Palo Alto, California, United States

UCSF Benioff's Children's Hospital

🇺🇸

San Francisco, California, United States

Children's National Medical Center

🇺🇸

Washington, District of Columbia, United States

Children's Healthcare of Atlanta

🇺🇸

Atlanta, Georgia, United States

National Institutes of Health Clinical Center

🇺🇸

Bethesda, Maryland, United States

Boston Children's Hospital

🇺🇸

Boston, Massachusetts, United States

University of Minnesota

🇺🇸

Minneapolis, Minnesota, United States

Memorial Sloan Kettering Cancer Center

🇺🇸

New York, New York, United States

Cincinnati Children's Hospital Medical Center

🇺🇸

Cincinnati, Ohio, United States

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