JSP191 Antibody Conditioning Regimen in MDS/AML Subjects Undergoing Allogenic Hematopoietic Stem Cell Transplantation
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ClinicalTrials.gov Identifier: NCT04429191 |
Recruitment Status :
Recruiting
First Posted : June 12, 2020
Last Update Posted : June 11, 2021
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
MYELODYSPLASTIC SYNDROME; MDS ACUTE MYELOID LEUKEMIA; AML | Biological: Humanized anti-CD117 Monoclonal Antibody (JSP191) | Phase 1 |
This is a Phase 1a/b study to evaluate the safety and tolerability of an antibody conditioning regimen known as JSP191, in combination with low dose radiation and fludarabine in subjects with Myelodysplastic Syndrome (MDS) or Acute Myeloid Leukemia (AML) undergoing allogenic blood stem cell transplantation.
Blood Stem Cell transplantation offers the only potentially curative therapy for many forms of Acute Myeloid Leukemia (AML) and for Myelodysplastic Syndrome (MDS). While standard of care conditioning regimens given prior to blood Stem Cell transplantation, such as standard TBI/Flu conditioning are well tolerated, they are associated with increased rates of relapse due to persistence of disease causing Hematopoietic Stem Cells and insufficient graft versus leukemia effect.
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 MDS/AML patients are depleted.
This study will investigate the safety and tolerability of adding JSP191 (an anti-CD117 monoclonal antibody therapy) to standard TBI/Flu conditioning regimen in adults with AML and MDS undergoing hematopoietic stem cell transplant.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 40 participants |
Allocation: | N/A |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1a/b Study to Evaluate the Safety & Tolerability of JSP191 in Combination With a Regimen of Low Dose Radiation & Fludarabine in Subjects With MDS or AML Undergoing Hematopoietic Cell Transplantation (HCT) |
Actual Study Start Date : | July 8, 2020 |
Estimated Primary Completion Date : | October 15, 2023 |
Estimated Study Completion Date : | December 8, 2023 |

Arm | Intervention/treatment |
---|---|
Experimental: Blood Stem Cell Transplant w/ anti-CD117 conditioning
The phase 1a portion of the study plans to assess approximately 3 planned dose cohorts of JSP191: 0.3 mg/kg, 0.6 mg/kg, and 1.0 mg/kg to determine the maximum tolerated dose for expansion. Subjects 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. The phase 1b portion of the study will enroll additional subjects at the expansion dose in order to further explore the safety, feasibility, and PK of that dose. |
Biological: Humanized anti-CD117 Monoclonal Antibody (JSP191)
Procedure: single intravenous infusion of JSP191 antibody
Other Name: JSP191 |
- The number of subjects experiencing adverse events and serious adverse events will be assessed. [ Time Frame: Up to 1 year post Donor Cell Transplant (28 days dose limiting toxicity period) ]The number of subjects experiencing adverse events and serious adverse events will be assessed.
- The number of dose limiting toxicities will be assessed. [ Time Frame: Up to 1 year post Donor Cell Transplant (28 days dose limiting toxicity period) ]The number of dose limiting toxicities will be assessed.
- The type of dose limiting toxicities will be assessed. [ Time Frame: Up to 1 year post Donor Cell Transplant (28 days dose limiting toxicity period) ]The type of dose limiting toxicities will be assessed.

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Key Inclusion Criteria:
-
AML/MDS as defined by specific criteria, including but not limited to the following subtypes:
- AML in CR
- MDS < 5% BM blasts
- MDS 5 - 10% BM blasts
- AML not in CR or MDS > 10% BM blasts
- Patients with human leukocyte antigen (HLA) matched related or unrelated donors
- Adequate end organ function as defined in study protocol
Key Exclusion Criteria:
- Patients with any acute or uncontrolled infections
- Patients receiving any other investigational agents
- Patients with active non-hematologic malignancy
- Prior allogeneic hematologic cell transplantation

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): NCT04429191
Contact: Clinical Trials, Jasper Therapeutics, Inc. | 650-549-1417 | ClinicalTrials@JasperTherapeutics.com |
United States, California | |
City of Hope Comprehensive Cancer Center | Recruiting |
Duarte, California, United States, 91010 | |
Contact: Nicole Lim, MD, MS nlim@coh.org | |
Stanford University | Recruiting |
Stanford, California, United States, 94305 | |
Contact: Lori Muffly, MD,MS lmuffly@stanford.edu | |
United States, Illinois | |
Rush University Medical Center | Recruiting |
Chicago, Illinois, United States, 60612 | |
Contact: Ankur Varma, MD, MPH ankur_varma@rush.edu | |
United States, Oregon | |
Oregon Health & Science University | Recruiting |
Portland, Oregon, United States, 97239 | |
Contact: Clinical Trials Information Line 503-494-1080 trials@ohsu.edu | |
United States, Utah | |
Huntsman Cancer Institute - University of Utah | Recruiting |
Salt Lake City, Utah, United States, 84112 | |
Contact: Catherine Lee, MD cancerinfo@hci.utah.edu | |
United States, Washington | |
Fred Hutchinson Cancer Research Center | Recruiting |
Seattle, Washington, United States, 98109 | |
Contact: Bart Scott, MD bscott@fredhutch.org |
Principal Investigator: | Lori Muffly, MD,MS | Stanford University | |
Principal Investigator: | Andrew Artz, MD,MS | City of Hope Medical Center | |
Principal Investigator: | Bart Scott, MD | Fred Hutchinson Cancer Center | |
Principal Investigator: | Catherine Lee, MD | Huntsman Cancer Institute/ University of Utah | |
Principal Investigator: | Arpita Gandhi, MD | Oregon Health and Science University | |
Principal Investigator: | Ankur Varma, MD,PhD | Rush University Medical Center |
Responsible Party: | Jasper Therapeutics, Inc. |
ClinicalTrials.gov Identifier: | NCT04429191 |
Other Study ID Numbers: |
JSP-CP-003 |
First Posted: | June 12, 2020 Key Record Dates |
Last Update Posted: | June 11, 2021 |
Last Verified: | June 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
ACUTE MYELOID LEUKEMIA AML MDS MYELODYSPLASTIC SYNDROME |
Leukemia, Myeloid Leukemia, Myeloid, Acute Preleukemia Myelodysplastic Syndromes Leukemia Neoplasms by Histologic Type Neoplasms |
Bone Marrow Diseases Hematologic Diseases Precancerous Conditions Antibodies Antibodies, Monoclonal Immunologic Factors Physiological Effects of Drugs |