Recruiting

Phase 1

MotixafortideSCD Stem Cell Mobilization and Apheresis Using Motixafortide

Sponsor:

St. Jude Children's Research Hospital

Code:

NCT06442761

Conditions

Sickle Cell Disease

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Motixafortide

Study Details

Brief summary:

This study is being done to see if the study drug, motixafortide, is safe in participants with sickle cell disease (SCD). Investigators also want to see if the drug will help the body increase the number of stem cells that can be collected for possible future transplant use.

PRIMARY OBJECTIVE

To characterize the safety and tolerability of motixafortide in participants with SCD as determined by the incidence of adverse events (AEs).

SECONDARY OBJECTIVES

To characterize the efficacy of a single dose (Part A) or two doses (Part B) of motixafortide for hematopoietic stem cell (HSC) mobilization and apheresis collection in participants with SCD as determined by the yield of CD34+ cells (CD34+ cells/kg).
To measure the mobilization effects of single-day (Part A) or daily dosing (Part B) dosing with motixafortide in the peripheral blood in participants with SCD as determined by peak peripheral blood CD34+ counts
To recommend a phase 2 dosing strategy based on safety, efficacy, and mobilization effects

Conditions

Sickle Cell Disease

Study ID

NCT06442761

Start date

Nov 14, 2024

Status verified date

Sep, 2026

Completion date

Jul, 2028

Anticipated

Primary completion date

Jan, 2028

Anticipated

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

Participants with severe sickle cell disease (SCD) who are ≥18 years of age and willing to donate autologous hematopoietic stem cells (HSCs) for advancing future gene therapy for SCD after collection of back-up product. Severe SCD, for the purpose of this study, will be defined as participants who are receiving chronic transfusion therapy due to SCD related complications or are eligible for or currently enrolled on an allogeneic transplant protocol.
Participant must have a documented diagnosis of SCD with documentation of SCD genotype by medical history
Participants should either have a central line in place, be able to undergo apheresis without the necessity of the insertion of a central venous catheter, or agree to have a central line placed if IV access is inadequate.
ECOG performance status/Karnofsky score/Lansky score ≥ 80
White blood cell (WBC) count >3.0 x 10\^9/L, absolute neutrophil count (ANC) >1.0 x 10\^9/L, and platelet count >150 x 10\^9/L, and hemoglobin >7.0 gm/dL
Adequate renal function defined as serum/plasma creatinine < 1.5 mg/dL and an estimated glomerular filtration rate (eGFR) of at least 60 mL/min/1.73 m\^2 based on the CKD-Epi equation or the St. Jude equation.
Adequate liver function defined as direct bilirubin < 2.5 times the upper limit of normal range; aspartate aminotransferase (AST) and alanine aminotransferase (ALT) < 5 times the upper limit of normal range.
Participant's cardiac function (i.e., ejection fraction >40%) and pulmonary status (i.e., no evidence of pulmonary hypertension) within the last 6 months must be sufficient to undergo apheresis, as assessed by the Principal Investigator or an independent physician evaluating the participant. If an assessment has not been done within the last 6 months, an echocardiogram will be performed.
Negative serologic tests for syphilis, hepatitis B and C, HIV, and HTLV-1/II
Feasible manual or automated exchange transfusion plan to achieve hemoglobin S (HbS) near 30% within one week of mobilization
Female participants of childbearing age should have a negative pregnancy test.
Participants of childbearing potential should agree to use of a highly effective form of contraception during treatment and for at least 1 month after the last dose of motixafortide. Women of childbearing potential must agree to use 2 methods of effective contraception: One barrier method (e.g. diaphragm, or condom or sponge, each of which are to be combined with a spermicide) and one hormonal method, unless she uses a highly effective method. Highly effective methods of contraception include:

Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation: oral, intravaginal, transdermal
Progestogen-only hormonal contraception associated with inhibition of ovulation: oral, injectable, implantable
Intrauterine device (IUD)
Intrauterine hormone-releasing system (IUS)
Bilateral tubal occlusion
Vasectomised partner
Sexual abstinence.

Exclusion Criteria:

Active and painful splenomegaly or splenomegaly (size greater than upper limit of normal on examination).
Participant who, by medical history, requires rare donor registry RBC units for transfusion, or is unable to receive routine transfusion. Eligible study participants must have undergone prior work-up for the presence of red cell alloantibodies and confirmation of available compatible blood product support
Known allergy to or contraindication for motixafortide administration, or medications routinely administered during apheresis
Participant who has had a prior autologous or allogeneic transplantation, inclusive of gene therapy
Active viral, bacterial, fungal, or parasitic infection.
History of cancer, excluding squamous carcinoma of the skin and cervical carcinoma in situ.
Participant who has received experimental therapy within 4 weeks prior to providing informed consent
Poorly controlled diabetes mellitus, as assessed by the Investigator
Concomitant treatment with alternative investigational agent unable to be held for 30 days
Unwillingness to use a highly effective method of contraception for 1 month after motixafortide
Pregnancy
Inability or unwillingness of research participant or legal guardian/ representative to give written informed consent.
Inability or unwillingness of research participant to hold hydroxyurea for 30 days prior to first dose of study drug

Study Design

Enrollment

20 participants

Anticipated

Allocation

Non randomized

Intervention Model

Sequential

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: Treatment-Arm A-Single Dose

Part A: Participants who enroll early will be assigned to Part A. Part A participants will get one dose of the study drug and one stem cell collection process.

experimental: Treatment-Arm B-Two Daily Doses

Part B: Participants who enroll later in the study will be assigned to Part B. Part B participants will get two doses of the study drug and two stem cell collection processes over two days (one on each day).

Interventions

Motixafortide

Given Subcutaneously (under the skin).

Primary outcome measure

To assess the safety and tolerability of motixafortide in participants with sickle cell disease (SCD) as determined by the incidence of adverse events. [ Time Frame: 0 - 30 days ]

Central Contacts and Locations

Central contacts

Alexis Leonard, MD

888-226-4343 referralinfo@stjude.org

Locations

University of Alabama at Birmingham

Recruiting

Birmingham, Alabama, United States, 35294

Contacts

Julie Kanter, MD

205-975-2837 jkanter@uabmc.edu

Principal Investigator:

Julie Kanter, MD

National Heart, Blood and Lung Institute-Cellular and Molecular Therapy Branch

Recruiting

Bethesda, Maryland, United States, 20814

Contacts

Matthew Hsieh, MD

301-273-5102 Matthewhs@nhlbi.nih.gov

Principal Investigator:

Matthew Hsieh, MD

St. Jude Children's Research Hospital

Recruiting

Memphis, Tennessee, United States, 38105

Contacts

Alexis Leonard, MD

888-226-4343 referralinfo@stjude.org

Principal Investigator:

Alexis Leonard, MD

More Information

Sponsor

St. Jude Children's Research Hospital

Last update posted

Sep 8, 2026

Last verified

Sep, 2026

Keywords

Stem Cell Mobilization
Apheresis
Motixafortide

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by St. Jude Children's Research Hospital on 2026-09-08.