SCIDPhase 1/2NCT02963064
JSP191 Antibody Targeting Conditioning in SCID Patients
A Phase 1/2 study testing Humanized anti-CD117 Monoclonal Antibody (JSP191) in people with SCID, run by Jasper Therapeutics, Inc. at 9 sites in United States.
Trial 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 Read more about this study
- Who is it for?
- Ages 3 months to 12 years
- Conditions the study is for
- SCID
- What is being tested?
- Humanized anti-CD117 Monoclonal Antibody (JSP191)
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 23 participants
- Where
- 9 sitesUnited States
- Study dates
- 20 Mar 2017to 7 Jul 2025
- Phase
- Phase 1/2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 3 months to 12 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Typical SCID as defined by Primary Immune Deficiency Treatment Consortia including but not limited to the following subtypes:
- T-, B+, NK-: IL-2Rcγ deficient, JAK3-deficient (no longer enrolling)
- T-, B-, NK+: RAG1/2 deficient, Artemis-deficient
- 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.
- Patients with human leukocyte antigen (HLA) matched related or unrelated donors
- Adequate end organ function as defined in study protocol
Show all 9Show fewer
- Age ≤ 12 years
- Prior donor of appropriate age (≥ 5 years old) available for re-collection of stem cells
- Previous allogeneic Hematopoietic Cell Transplantation HCT (≥ 6 months post initial transplant) with poor graft function
Who cannot join
- Patients with any acute or uncontrolled infections
- Patients receiving any other investigational agents, or concurrent biological, chemotherapy, or radiation therapy
- Patients with active malignancies
- Active GVHD within 6 months prior to enrollment, or on immunosuppressive therapy for GVHD
Trial locations and contacts
9 sites in 1 country.
9 sites in 1 country
United States9 sites
Children's Healthcare of Atlanta
Atlanta, Georgia, 30322
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892
Cincinnati Children's Hospital Medical Center
Cincinnati, Ohio, 45229
UCLA Mattel Children's Hospital
Los Angeles, California, 90095
University of Minnesota
Minneapolis, Minnesota, 55455
Memorial Sloan Kettering Cancer Center
New York, New York, 10065
Lucile Packard Children's Hospital
Palo Alto, California, 94304
UCSF Benioff's Children's Hospital
San Francisco, California, 94158
Children's National Medical Center
Washington D.C., District of Columbia, 20010
About this study
Official title: A Phase 1/2 Study to Evaluate the Safety, Tolerability, and Efficacy of JSP191 for Hematopoietic Cell Transplantation Conditioning to Achieve Engraftment and Immune Reconstitution in Subjects With SCID
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
Read the 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.
- Conditions
- SCID
- Being tested
- Humanized anti-CD117 Monoclonal Antibody (JSP191)
- Keywords
- Immunodeficiency, Pediatric, SCID, Bone Marrow Transplantation, GVHD, Stem Cells, Chimerism, Transplant, BMT
- Medical subject headings
- Immunologic Deficiency Syndromes
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Humanized anti-CD117 Monoclonal Antibody (JSP191)Biological
Procedure: single intravenous infusion of JSP191 antibody
| Study group | Role | What they receive |
|---|---|---|
| Blood Stem Cell Transplant w/ anti-CD117 conditioning | Experimental | 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. Receives: Biological: Humanized anti-CD117 Monoclonal Antibody (JSP191) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Phase 1: Safety and tolerability of JSP191 as conditioning therapy in SCID patients undergoing HCT: adverse events
The number of subjects experiencing dose limiting toxicities including adverse events and serious adverse events will be assessed.
Measured: Up to 5 years post Donor Cell Transplant (28 days dose limiting toxicity period)
Phase 2: Efficacy of JSP191 as conditioning therapy in SCID patients
To enable engraftment of allogeneic CD34+ hematopoietic cells, as determined by CD15+ donor myeloid chimerism
Measured: Up to 24 weeks post Donor Cell Transplant
Phase 2: Efficacy of JSP191 as conditioning therapy in SCID patients
To enable immune reconstitution, as determined by the production of naive T cells
Measured: Weeks 36-104 post Donor Cell Transplant
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Nov 2016 (estimated)
- Study start20 Mar 2017
- Primary completion7 Jul 2025
- Study completion7 Jul 2025
Why it stopped: Sponsor Decision - terminated due to changes in company priorities and not related to safety concerns.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SCIDStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1/2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 23 participants (actual)
Sponsor and investigators
- Lead sponsor
- Jasper Therapeutics, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Rajni A. Agarwal-Hashmi, M.D., Principal investigator, Lucile Packard Children's HospitalChristopher C. Dvorak, M.D., Principal investigator, UCSF Benioff's Children's HospitalJoseph H. Oved, M.D., Principal investigator, Memorial Sloan Kettering Cancer CenterTheodore B. Moore, M.D., Principal investigator, University of California, Los AngelesSharat Chandra, M.D., Principal investigator, Children's Hospital Medical Center, CincinnatiChristen L Ebens, M.D., MPH, Principal investigator, University of MinnesotaHarry L Malech, M.D., Principal investigator, National Institutes of Health Clinical Center (CC)Shanmuganathan Chandrakasan, M.D., Principal investigator, Children's Healthcare of Atlanta
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02963064
- Sponsor's protocol ID
- JAS-BMT-CP-001
- Status last verified
- Jul 2025
- First submitted
- 2 Nov 2016
- Last updated
- 28 Jul 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: Data collected is for future publication
Study at a glance
From the registry record, last updated by the sponsor on 28 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1/2 Study to Evaluate the Safety, Tolerability, and Efficacy of JSP191 for Hematopoietic Cell Transplantation Conditioning to Achieve Engraftment and Immune Reconstitution in Subjects With SCID
- ClinicalTrials.gov ID
- NCT02963064
- Acronym / sponsor ID
- JAS-BMT-CP-001
- Conditions
- SCID
- Keywords
- Immunodeficiency, Pediatric, SCID, Bone Marrow Transplantation, GVHD, Stem Cells, Chimerism, Transplant
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Sponsor Decision - terminated due to changes in company priorities and not related to safety concerns.
- Enrolment
- 23 participants (actual)
- Lead sponsor
- Jasper Therapeutics, Inc.Industry (pharma, biotech, devices)
- Study start
- 20 Mar 2017 (actual)
- Primary completion
- 7 Jul 2025 (actual)
- Study completion
- 7 Jul 2025 (actual)
- First posted
- 15 Nov 2016 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Blood Stem Cell Transplant w/ anti-CD117 conditioning | Experimental | Biological: Humanized 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. |
Who may qualify
- Ages
- 3 months to 12 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (9 listed)
- Typical SCID as defined by Primary Immune Deficiency Treatment Consortia including but not limited to the following subtypes:
- Patients with human leukocyte antigen (HLA) matched related or unrelated donors
- Adequate end organ function as defined in study protocol
- Age ≤ 12 years
- Prior donor of appropriate age (≥ 5 years old) available for re-collection of stem cells
Key exclusion criteria (4 listed)
- Patients with any acute or uncontrolled infections
- Patients receiving any other investigational agents, or concurrent biological, chemotherapy, or radiation therapy
- Patients with active malignancies
- Active GVHD within 6 months prior to enrollment, or on immunosuppressive therapy for GVHD
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Humanized anti-CD117 Monoclonal Antibody (JSP191)Procedure: single intravenous infusion of JSP191 antibody | Biological | Blood Stem Cell Transplant w/ anti-CD117 conditioning |
Primary outcome
Phase 1: Safety and tolerability of JSP191 as conditioning therapy in SCID patients undergoing HCT: adverse events
Time frame: Up 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 patients
Time frame: Up to 24 weeks post Donor Cell Transplant
To enable engraftment of allogeneic CD34+ hematopoietic cells, as determined by CD15+ donor myeloid chimerism
Phase 2: Efficacy of JSP191 as conditioning therapy in SCID patients
Time frame: Weeks 36-104 post Donor Cell Transplant
To enable immune reconstitution, as determined by the production of naive T cells
Results and safety
The study was stopped early (reason given: Sponsor Decision - terminated due to changes in company priorities and not related to safety concerns.). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jul 2025.
- Individual participant dataSharing planned: No. Data collected is for future publication
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Rajni A. Agarwal-Hashmi, M.D. principal investigator
Lucile Packard Children's Hospital
Christopher C. Dvorak, M.D. principal investigator
UCSF Benioff's Children's Hospital
Joseph H. Oved, M.D. principal investigator
Memorial Sloan Kettering Cancer Center
9 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing Humanized anti-CD117 Monoclonal Antibody (JSP191) in people with SCID, run by Jasper Therapeutics, Inc. at 9 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 28 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 9 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study was stopped early (reason given: Sponsor Decision - terminated due to changes in company priorities and not related to safety concerns.). Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Phase 1: Safety and tolerability of JSP191 as conditioning therapy in SCID patients undergoing HCT: adverse events (time frame: Up to 5 years post Donor Cell Transplant (28 days dose limiting toxicity period)). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jul 2025.