TMLI and Alemtuzumab for Treatment of Sickle Cell Disease

December 31, 2025 updated by: City of Hope Medical Center

A Pilot Study of Nonmyeloablative Regimen Using Total Marrow and Lymphoid Irradiation for Irradiation Sparing of Bystander Organs in Hematopoietic Cell Transplantation From Matched Related or Unrelated Donor in Patients With Sickle Cell Disease

This phase I trial tests the safety and effectiveness of total marrow and lymphoid irradiation (TMLI) and alemtuzumab as a conditioning regimen in patients with sickle cell disease. Conditioning regimens are treatments used to prepare a patient for stem cell transplantation. A stem cell transplant is a procedure in which a person receives blood stem cells, which make any type of blood cell. A conditioning regimen may include chemotherapy, monoclonal antibody therapy, and radiation to the entire body. It helps make room in the patient's bone marrow for new blood stem cells to grow, and helps prevent the patient's body from rejecting the transplanted cells. Alemtuzumab is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Graft-versus-host disease (GVHD) is a complication that may occur after hematopoietic cell transplantation (HCT) in which donated cells view the recipient's cells as foreign and attack them. Giving TMLI and alemtuzumab may help reduce organ damage that can be caused by radiation and decrease the risk of GVHD.

Study Overview

Detailed Description

PRIMARY OBJECTIVE:

I. Evaluate the safety and feasibility of a fixed TMLI dose of 600 cGy with alemtuzumab as non-myeloablative conditioning (NMC) regimen in patients with sickle cell disease to achieve stable engraftment by Day +100 post HCT.

SECONDARY OBJECTIVES:

I. Assess the hematopoietic recovery by determining donor neutrophil engraftment, platelet engraftment.

II. Assess irradiation doses to non-target organs (lungs, heart, liver, spleen, kidneys, and gonads).

III. Assess the incidence of acute GvHD (grade II - IV) during the first 100 days after transplantation and chronic GvHD at 1 year post-HCT.

IV. Assess overall, event-free, and disease free survival at 1 year post-HCT. V. Assess donor chimerism at day +100 and 1 and 2 years after HCT.

EXPLORATORY OBJECTIVES:

I. Assess immune reconstitution post HCT on baseline, then on days +15, +30, +60, and +180, and 1-year post-HCT. II. Assessment of quality of life at baseline, Day+100, Day +180 and at 1-year post-HCT.

III. Define the impact of sickle cell disease (SCD) including inflammation on the bone marrow microenvironment and hematopoietic cells function at baseline.

IV. Monitor treatment response noninvasively on the recovery of bone marrow microenvironment (hematopoietic and vascular).

V. Monitor treatment response noninvasively on cerebral blood flow (CBF).

OUTLINE:

Patients receive alemtuzumab intravenously (IV) over 4 hours once daily (QD) on days -7 to -3. Patients undergo TMLI twice daily (BID) on day -2. Patients also undergo HCT on day 0 and receive sirolimus on day -1 and day 0.

After study treatment, patients are followed up on day 30, and for up to 2 years.

Study Type

Interventional

Enrollment (Actual)

2

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • Duarte, California, United States, 91010
        • City of Hope Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

8 years to 36 years (Child, Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Documented informed consent of the participant and/or legally authorized representative

    • Assent, when appropriate, will be obtained per institutional guidelines
  • Registered into Risk Evaluation and Mitigation Strategies (REMS) program
  • Age: 12-40 years
  • Eastern Cooperative Oncology Group (ECOG) performance status =< 2
  • Have a diagnosis of sickle cell disease, be at a high risk for disease related morbidity or mortality, which must be defined by one of the following disease status criteria:

    • Significant neurologic event (stroke) or any neurological deficit lasting > 24 hours; or increased transcranial Doppler velocity (> 200 m/s).
    • History of one or more episodes of acute chest syndrome (ACS) in the 2-year period preceding enrollment despite the institution of supportive care measures (i.e. asthma therapy and/or hydroxyurea).
    • History of one or more severe vaso-occlusive pain crises per year in the 2-year period preceding enrollment despite the institution of supportive care measures (i.e. a pain management plan and/or treatment with hydroxyurea).
    • Recurrent priapism requiring medical therapy.
    • Osteonecrosis of two or more joints despite the institution of supportive care measures.
    • Prior treatment with regular red blood cell (RBC) transfusion therapy, defined as receiving 8 or more transfusions per year for > 1 year to prevent vaso-occlusive clinical complications (i.e. pain, stroke, and acute chest syndrome)
    • Echocardiograph finding of tricuspid valve regurgitation jet (TRJ) velocity >= 2.5 m/sec.
  • Have a related donor who is matched on at least 8/10 human leukocyte antigen (HLA)-A, B, C, and DRB1 Loci
  • Total bilirubin =< 2.5 x upper limit normal (ULN( (unless has Gilbert's disease) (performed within 30 days prior to day 1 of protocol)
  • Aspartate aminotransferase (AST) =< 1.5 x ULN (performed within 30 days prior to day 1 of protocol)
  • Alanine aminotransferase (ALT) =< 1.5 x ULN (performed within 30 days prior to day 1 of protocol)
  • Creatinine clearance (CrCl) of >= 60 mL/min per 24 hour urine test or the Cockcroft-Gault formula (performed within 30 days prior to day 1 of protocol)
  • If not receiving anticoagulants: International Normalized Ratio (INR) OR Prothrombin (PT) =< 1.5 x ULN (performed within 30 days prior to day 1 of protocol)

    • If on anticoagulant therapy: PT must be within therapeutic range of intended use of anticoagulants
  • If not receiving anticoagulants: Activated Partial Thromboplastin Time (aPTT) =<1.5 x ULN (performed within 30 days prior to day 1 of protocol)

    • If on anticoagulant therapy: aPTT must be within therapeutic range of intended use of anticoagulants
  • Left ventricular ejection fraction (LVEF) >= 50% (performed within 30 days prior to day 1 of protocol)

    • Note: To be performed within 28 days prior to Day 1 of protocol therapy.
  • If able to perform pulmonary function tests: Forced expiratory volume in 1 second (FEV1), force vital capacity (FVC), and diffused lung capacity of carbon monoxide (DLCO) (diffusion capacity) >= 50% of predicted (corrected for hemoglobin)

    • If unable to perform pulmonary function tests: Oxygen (O 2) saturation > 92% on room air
    • Note: To be performed within 28 days prior to Day 1 of protocol therapy.
  • Seronegative for human immunodeficiency virus (HIV) antigen (Ag)/antibody (Ab) combo, hepatitis C virus (HCV), active hepatitis B virus (HBV) (surface antigen negative), and syphilis (rapid plasma regain [RPR])

    • If positive, hepatitis C ribonucleic acid (RNA) quantitation must be performed
  • Meets other institutional and federal requirements for infectious disease titer requirements

    • Note Infectious disease testing to be performed within 28 days prior to day 1 of protocol therapy
  • Women of childbearing potential (WOCBP): negative urine or serum pregnancy test

    • If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be require.
  • Agreement by females and males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least Six months after the last dose of protocol therapy.

    • Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for > 1 year (women only)
  • DONOR: Age =< 60 years
  • DONOR: Medical history and physical examination confirm good health status as defined by institutional standards
  • DONOR: Serologies for: Hepatitis B (HBV) Core Antibody, HIV I/II Antibody, human T-lymphotropic virus (HTLV) - I/II antibody, HCV antibody, Hepatitis B surface antigen, Serologic Test for Syphilis, HIV-1/HCV/HBV nucleic acid, West Nile virus nucleic acid, Trypanosoma cruzi antibody, Cytomegalovirus (CMV) antibody, (AKA: Donor Room Serologies)
  • DONOR: Female donors of childbearing potential must have a negative serum or urine beta human chorionic gonadotropin (b-HCG) test within 30 days of initiation of conditioning, 30 days of patients admission for conditioning and 7 days of mobilization or bone marrow harvest.
  • DONOR: The donor must be informed of the investigational nature of this study and have signed a consent form in accordance with Federal Guidelines and the guidelines of the participating institution

Exclusion Criteria:

  • Prior allogeneic or autologous stem cell transplant
  • Patients who are receiving any other investigational agents, or concurrent biological, chemotherapy, or radiation therapy.
  • History of allergic reactions attributable to compounds of similar chemical or biologic composition to study agent
  • Patients with any active malignancy are ineligible for this study, other than non-melanoma skin cancers
  • Medical problem or neurologic/psychiatric dysfunction which would impair patient ability to be compliant with the medical regimen and to tolerate transplantation or would prolong hematologic recovery which in the opinion of the principal investigator would place the recipient at unacceptable risk.
  • Active infection requiring antibiotics
  • Females only: Pregnant or breastfeeding
  • Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns with clinical study procedures
  • Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)
  • DONOR: Evidence of active infection
  • DONOR: Medical or physical reason which makes the donor unlikely to tolerate or cooperate with growth factor therapy and leukapheresis if donating peripheral stem cells or unlikely to tolerate general anesthesia and bone marrow collection if donating a bone marrow
  • DONOR: Factors which place the donor at increased risk for complications from leukapheresis or granulocyte colony-stimulating Factor (G-CSF) therapy if donating peripheral stem cells or general anesthesia and bone marrow collection if donating a bone marrow
  • DONOR: Lactating female or, if of child-bearing potential, is unwilling to implement adequate birth control
  • DONOR: HIV positive
  • DONOR: Prior radiation therapy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Treatment (TMLI, alemtuzumab)
Patients receive alemtuzumab IV over 4 hours QD on days -7 to -3. Patients undergo TMLI BID on day -2. Patients also undergo HCT on day 0 and receive sirolimus on day -1 and day 0.
Undergo HCT
Other Names:
  • HSCT
  • HCT
  • Hematopoietic Stem Cell Transplantation
  • stem cell transplantation
  • Hematopoietic Stem Cell Infusion
  • Stem Cell Transplant
Given IV
Other Names:
  • Campath
  • Campath-1H
  • Lemtrada
  • Monoclonal Antibody Campath-1H
  • MabCampath
  • Anti-CD52 Monoclonal Antibody
  • LDP-03
Undergo TMLI
Other Names:
  • IMRT
  • Intensity Modulated RT
  • Intensity-Modulated Radiotherapy
  • Radiation, Intensity-Modulated Radiotherapy
Medication to prevent the development of graft-versus-host disease (GVHD)
Other Names:
  • Rapamycin
  • Rapamune
  • AY 22989
  • RAPA
  • SILA 9268A
  • WY-090217

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of adverse events
Time Frame: Up to day 100 post-transplant
Will be scored on the Bearman Scale National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version (v) 5.0. The proportion of patients with the unacceptable adverse events will be calculated along with the appropriate Clopper-Pearson 90% confidence intervals.
Up to day 100 post-transplant
Feasibility
Time Frame: Up to 2 years
Feasibility will be defined as engraftment that would be sufficient to reduce sickle cell disease (SCD) burden (Any donor chimerism with Hgb S =< 30%).
Up to 2 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Platelet engraftment
Time Frame: Up to 2 years
Platelet engraftment will be defined as independence from platelet transfusion for at least 7 days with a platelet count of more than >20 × 10^9/L
Up to 2 years
Time to acute graft-versus-host disease (grades 2-4 and 3-4) until day +100 after transplant
Time Frame: Up to 2 years
Acute Graft versus Host Disease (aGVHD) of grades 2-4 and 3-4: Documented/biopsy proven acute graft versus host disease is graded according to the Consensus Grading. Time to event is measured from date of stem cell infusion to document/biopsy proven acute GVHD onset date (within the first 100 days post-transplant) and will be used to estimate the cumulative incidence.
Up to 2 years
Time to chronic graft-versus-host disease for up to one year after transplant
Time Frame: Up to 2 years

Chronic Graft versus Host Disease (cGVHD): chronic Graft versus Host Disease (aGVHD) of grades 2-4 and 3-4:

Documented/biopsy proven chronic graft versus host disease is scored according to NIH Consensus Staging. Time to event is measured from date of stem cell infusion to the documented/biopsy proven chronic GVHD onset date and will be used to estimate the cumulative incidence.

Up to 2 years
Overall survival (OS)
Time Frame: From start of protocol therapy to death, or last follow-up, whichever comes first, assessed up to 2 years
Patients are considered a failure for this endpoint if they die, regardless of cause.
From start of protocol therapy to death, or last follow-up, whichever comes first, assessed up to 2 years
Event-free survival (EFS)
Time Frame: From start of protocol therapy to death, graft failure, or last follow-up, whichever comes first, assessed up to 2 years
Patients are considered a failure for this endpoint if they graft failure, or die, regardless of cause. Time to this event is the time from start of protocol therapy to death, graft failure, or last follow-up, whichever comes first.
From start of protocol therapy to death, graft failure, or last follow-up, whichever comes first, assessed up to 2 years
Disease-free Survival (DFS)
Time Frame: From date of stem cell infusion to death, disease relapse/progression, or last follow-up, whichever comes first, assessed up to 2 years
Patients are considered a failure for this endpoint if they die (regardless of cause) or experience disease progression or relapse.
From date of stem cell infusion to death, disease relapse/progression, or last follow-up, whichever comes first, assessed up to 2 years

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Immune cell reconstitution
Time Frame: Up to 2 years
Immune cell reconstitution will be assessed by flow cytometry analysis
Up to 2 years
Quality of life - PedsQL
Time Frame: Up to 2 years

Items on the PedsQL Generic Core Scales are reverse scored and transformed to a 0-100 scale.

Higher scores indicate better health related quality of life:

0 ("Never") = 100

  1. ("Almost Never") = 75
  2. ("Sometimes") = 50
  3. ("Often") = 25
  4. ("Almost Always") = 0

For adults 16-item QOLS patients will be given a copy of the 7-point response scale ["delighted" (7), "pleased" (6), "mostly satisfied" (5), "mixed" (4), "mostly dissatisfied" (3), "unhappy" (2), "terrible" (1).] The QOLS scores will be summed so that a higher score indicates higher quality of life. Average total score for healthy populations is about 90. However, like many QOL instruments, the means tend to be quite negatively skewed with most patients reporting some degree of satisfaction with most domains of their lives.

Up to 2 years
Bone marrow environment inflation - levels of inflammatory cytokines
Time Frame: Baseline only (pre-conditioning)
The long-term impact of Sickle Cell Disease on patients bone marrow will be measured by evaluation of the levels of inflammatory cytokines in the bone marrow before treatment with TMLI and alemtuzumab.
Baseline only (pre-conditioning)
Bone marrow environment inflation - stem cell function
Time Frame: Baseline only (pre-conditioning)
The long-term impact of Sickle Cell Disease on patients bone marrow will be measured by evaluation of the stem cell function in the bone marrow before treatment with TMLI and alemtuzumab.
Baseline only (pre-conditioning)
Treatment response on bone marrow environment and CBF
Time Frame: Up to 1 year
Treatment response on bone marrow environment and CBF will be assessed by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). All imaging will be performed before the start of the treatment and post-transplant at days 30, 100, 180, and at one year, coinciding with time points when clinical standard biopsy samples are obtained.
Up to 1 year

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Anna Pawlowska, City of Hope Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 13, 2022

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 1, 2026

Study Registration Dates

First Submitted

May 3, 2022

First Submitted That Met QC Criteria

May 18, 2022

First Posted (Actual)

May 20, 2022

Study Record Updates

Last Update Posted (Actual)

January 5, 2026

Last Update Submitted That Met QC Criteria

December 31, 2025

Last Verified

December 1, 2025

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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