NCT05905770

Brief Summary

Rationale: Non-myeloablative allogeneic stem cell transplantation (SCT) has become a feasible curative treatment option for sickle cell disease (SCD) patients with an available matched sibling donor. Chemotherapy free conditioning with alemtuzumab and 3 Gy total body irradiation (TBI) is increasingly being used as preferred conditioning scheme for these patients. This regimen typically results in mixed donor chimerism and has only few toxic effects. However, the risk of graft failure (rejection) is still significant, with an occurrence of 13% in the latest series. Levels of T cell chimerism are crucial for the success of this kind of transplantation. A donor T cell level of at least 50% at 1-year post-transplantation seems to be sufficient to allow the discontinuation of immunosuppressive medication without risk of graft rejection. Low levels of alemtuzumab prior to or shortly after SCT are thought to facilitate rejection of the donor graft. Recently, a positive correlation between alemtuzumab levels on day+14 was found with levels of T cell chimerism +2 and +4 months post-transplantation in adult SCD patients receiving matched sibling donor SCT. However, in this study alemtuzumab levels prior to the infusion of hematopoietic stem cells and beyond day +28 post-transplantation were not measured. Furthermore, the alemtuzumab levels were measured in 2 patient groups undergoing two different conditioning regimens. Here, the investigators aim to thoroughly investigate the correlation of alemtuzumab levels and T cell chimerism. This will be the first study involving SCD patients receiving matched sibling donor SCT with alemtuzumab/TBI conditioning that includes alemtuzumab level measurements before the infusion of hematopoietic stem cells and beyond 1-month post-transplantation. Findings from this study will improve the insights into the etiology of graft failure in these patients and might ultimately lead to a more personalized approach in dosing alemtuzumab in order to achieve a more robust and stable engraftment of donor hematopoietic stem cells. Objectives: To investigate whether serum alemtuzumab concentrations are predictive of the robustness of engraftment in SCD patients undergoing a matched sibling donor transplantation with alemtuzumab/TBI conditioning resulting in mixed chimerism. Study design: Prospective observational laboratory study. Serum alemtuzumab concentration will be measured at various time points before and after stem cell infusion (days -3, 0, +7, +14, +28, +60). Study population: Adult SCD patients that are planned for a matched sibling donor transplantation with alemtuzumab/TBI conditioning at the Amsterdam UMC. Main study parameters/endpoints: The correlation between serum alemtuzumab concentration and levels of donor chimerism. Secondary endpoints: correlation between serum alemtuzumab levels and patients with and without successful engraftment. Correlation of serum alemtuzumab levels and the dosing of alemtuzumab in mg/kg, number of patient lymphocyte count and total number of infused enucleated donor-derived cells.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
20

participants targeted

Target at below P25 for all trials

Timeline
Completed

Started Jul 2022

Typical duration for all trials

Geographic Reach
1 country

1 active site

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

July 15, 2022

Completed
11 months until next milestone

First Submitted

Initial submission to the registry

June 7, 2023

Completed
8 days until next milestone

First Posted

Study publicly available on registry

June 15, 2023

Completed
1.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

November 1, 2024

Completed
1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

November 1, 2025

Completed
Last Updated

June 22, 2023

Status Verified

June 1, 2023

Enrollment Period

2.3 years

First QC Date

June 7, 2023

Last Update Submit

June 20, 2023

Conditions

Keywords

Sickle Cell DiseaseAllogeneic stem cell transplantationAlemtuzumab

Outcome Measures

Primary Outcomes (1)

  • The correlation between serum alemtuzumab concentration and donor T cell chimerism.

    +1 year post-transplantation

Secondary Outcomes (3)

  • o The differences in serum alemtuzumab concentration at the various time points (T1-T7) between patients with and without successful engraftment. Successful engraftment is defined as donor T cell chimerism >50% at 1-year post-transplantation.

    +1 year post-transplantation

  • o The correlation between the dosing of alemtuzumab in mg/kg, the number of patient lymphocytes and alemtuzumab levels at the various time points (T1-T7).

    +1 year post-transplantation

  • o The correlation between total number of infused enucleated donor-derived cells and the amount of decrease of alemtuzumab levels before and after stem cell infusion (T2 and T3).

    +1 year post-transplantation

Study Arms (1)

Sickle cell disease patients aged 16 years and older with an available matched sibling donor.

Alemtuzumab 1mg/kg/TBI 3Gy conditioning

Drug: Alemtuzumab Injection [Campath]

Interventions

Alemtuzumab 1mg/kg

Sickle cell disease patients aged 16 years and older with an available matched sibling donor.

Eligibility Criteria

Age16 Years+
Sexall
Healthy VolunteersNo
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Adult SCD patients that are planned for a matched sibling donor transplantation with alemtuzumab/TBI conditioning at the Amsterdam UMC.

You may qualify if:

  • Age 16 years and older
  • High performance liquid chromatography (HPLC) confirmed diagnoses of SCD (all genotypes)
  • Planned for a non-myeloablative matched sibling donor SCT with alemtuzumab/TBI at the Amsterdam UMC
  • Willing and able to provide written informed consent

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Amsterdam Medical Centre

Amsterdam, 1105AZ, Netherlands

RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

Peripheral blood (serum)

MeSH Terms

Conditions

Anemia, Sickle Cell

Interventions

Alemtuzumab

Condition Hierarchy (Ancestors)

Anemia, Hemolytic, CongenitalAnemia, HemolyticAnemiaHematologic DiseasesHemic and Lymphatic DiseasesHemoglobinopathiesGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and Abnormalities

Intervention Hierarchy (Ancestors)

Antibodies, Monoclonal, HumanizedAntibodies, MonoclonalAntibodiesImmunoglobulinsImmunoproteinsBlood ProteinsProteinsAmino Acids, Peptides, and ProteinsSerum GlobulinsGlobulins

Study Officials

  • Erfan Nur, MD, PhD

    Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Prinicpal investigator

Study Record Dates

First Submitted

June 7, 2023

First Posted

June 15, 2023

Study Start

July 15, 2022

Primary Completion

November 1, 2024

Study Completion

November 1, 2025

Last Updated

June 22, 2023

Record last verified: 2023-06

Locations