Extension Study (Extended Access) of Syk-inhibition Using Fostamatinib to Treat Posttransplant Immune-mediated Cytopenias

NCT05509582 | Withdrawn Phase 2 FDA Drug

• 2 other identifiers: 10000760000760-H
• Study Type: interventional
• Target: N/A
• Locations: 1 country
• Sites: 1

Brief Summary

Background: People who have a blood stem cell transplant can sometimes develop cytopenia. This means that their levels of one or more types of blood cell, such as the red cells or platelets, are lower than they should be. This can occur because a person s immune system might attack these cells after a stem cell transplant. Up to 20% of people who have blood stem cell transplants develop cytopenias, which can lead to anemia, severe bleeding, infections, and other problems. Treatments are needed to help keep blood cell levels stable after blood stem cell transplant. Objective: To evaluate the long-term effects of a study drug (fostamatinib) in people with cytopenia after a blood stem cell transplant. Eligibility: People who responded well to fostamatinib in an earlier study. Design: Participants will be screened. They will have a physical exam and blood tests. Fostamatinib is an oral tablet taken by mouth. Participants will take the pills at the same dose and frequency as they did during the previous study. They will take the pills for up to 21 months. The dosage of the drug may be reduced over time if their blood cell levels are stable. Participants will have a medical assessment every month. This can be with their local doctor or at the NIH clinic. Participants will have blood tests every 3 months. Participants will have a follow-up visit after they stop taking the drug. Their vital signs will be taken, and they will have blood drawn. They will answer questions about their health.

Conditions

Immune Mediated Anemia; Immune Mediated Thrombocytopenia; Chronic GVHD

Keywords

Allogeneic Hematopoietic Stem Cell Transplant; Graft Versus Host Disease; Spleen Tyrosine Kinase (Syk) Inhibitor

Outcome Measures

Primary Outcomes (1)

• Proportion of subjects who are able to maintain hematologic recovery

  Proportion of subjects who are able to maintain hematologic recovery (as defined below) by the end of 12 weeks on the extended access trial (total of 24 weeks fostamatinib treatment). Hematologic recovery is defined as: Hemoglobin \>=10 g/dL (or at least \>=2 g/dL above baseline) in subjects enrolled with post-transplant anemia. In subjects with symptomatic anemia, a hemoglobin increase of at least \>=2 g/dL above baseline is required OR Platelets \>= 50 x 109/L (or at least =20 x 10\^9/L above baseline) in subjects enrolled with post-transplant thrombocytopenia OR Both of the above criteria in subjects with post-transplant Evan s syndrome

  12 weeks

Secondary Outcomes (4)

• Proportion of subjects who are able to taper off fostamatinib by >33% while maintaining hematologic recovery

  106 weeks

• Change in the dose of other immunosuppressive agents

  12 weeks

• Proportion of subjects who are able to completely taper off fostamatinib while maintaining hematologic recovery

  106 weeks

• Change in corticosteroid dose

  12 weeks

Study Arms (1)

Fostamatinib Arm

EXPERIMENTAL

The subjects will receive oral fostamatinib daily for up to 2 years.

Drug: fostamatinib

Interventions

fostamatinib DRUG

Subjects will receive fostamatinib at the same dose as the dose they receive at the time of rollover. The dose could be reduced to 100mg daily, 150 mg daily, 100 mg twice a day if a dose-limiting adverse event occurred. After the initial 12 weeks on the extended access (total of 24 weeks of treatment), subjects will have the option to start tapering fostamatinib if they are maintaining hematologic recovery. Subjects with persistent (=2 readings, 2 weeks apart) loss of hematologic response, defined as Hb\<9g/dL and/or PLT\< 30 X 10\^9/L can increase their dose to next higher dose. Once count stabilization again occurs, a slow dose reduction to next lowest dose (100mg or 150mg) can be performed to identify the lowest dose necessary to keep counts over these thresholds.

Fostamatinib Arm

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Subjects who were enrolled on phase II trial of fostamatinib and deemed responders at the time of rollover to the extended access trial which is defined as:
• Hemoglobin \>= 9 g/dL (or at least \>= 1 g/dL above baseline) in subjects enrolled with posttransplant anemia without transfusion support, at least once during the 12-week phase II trial.
• Platelets \>= 30 X 10\^9/L (or at least \>= 10 X 10\^9/L above baseline) without transfusion support, at least once during the 12-week phase II trial, in subjects enrolled with posttransplant thrombocytopenia
• Either of the above criteria in subjects with posttransplant Evans syndrome
• Completed the end of study visit (week 12) on the initial protocol (A Phase II Study of Syk-inhibition using Fostamatinib to treat Post-Transplant Immune-mediated Cytopenias).
• Female patients of reproductive potential agree to avoid pregnancy through abstinence or the use two forms of highly effective birth control during and for 1 month after the last study treatment and agree not to donate eggs during this time.
• Male patients of reproductive potential agree to avoid pregnancy of a partner through abstinence or the use two forms of highly effective birth control during and for 1 month after the last study treatment and agree not to donate sperm during this time.

You may not qualify if:

• Severe psychiatric illness or mental deficiency sufficient to make making informed consent impossible
• Positive pregnancy test for women of childbearing age within 1 week or being actively lactating
• Uncontrolled hypertension (systolic blood pressure \>140mmHg or diastolic blood pressure \>90mmHg)
• ALT or AST \>3 times the upper limit of normal
• Patients who have a history of medical disorders, that in the investigator's opinion, could affect the conduct of the study or the absorption, metabolism or excretion of the study drug are excluded.
• Patients with evidence of graft rejection (based on clinical suspicion supported by BM biopsy data and/or chimerism studies and/or MLR)
• Neutropenia, defined as absolute neutrophil count \<= 1.0 X 10\^9/L
• Non-immune mediated cytopenias. Etiologies including, but not limited to, cytopenias due to HIV infection, lymphoproliferative disorders, myelodysplasia/acute leukemia, drug-induced thrombocytopenia, thrombotic microangiopathies, acute bleeding, consumptive coagulopathy, fever, infections leading to cytopenia, medications induced cytopenias, thrombotic microangiopathies (disseminated intravascular coagulation), splenomegaly or hemophagocytic lymphohistiophagocytosis, relapse of primary disease.

Sponsors & Collaborators

• National Heart, Lung, and Blood Institute (NHLBI): lead

Study Sites (1)

National Institutes of Health Clinical Center

Bethesda, Maryland, 20892, United States

Location

Related Links

• NIH Clinical Center Detailed Web Page

MeSH Terms

Conditions

Purpura, Thrombocytopenic, Idiopathic; Bronchiolitis Obliterans Syndrome; Graft vs Host Disease

Interventions

fostamatinib

Condition Hierarchy (Ancestors)

Purpura, Thrombocytopenic; Purpura; Blood Coagulation Disorders; Hematologic Diseases; Hemic and Lymphatic Diseases; Thrombotic Microangiopathies; Thrombocytopenia; Blood Platelet Disorders; Cytopenia; Hemorrhagic Disorders; Autoimmune Diseases; Immune System Diseases; Hemorrhage; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Skin Manifestations; Signs and Symptoms; Organizing Pneumonia; Bronchiolitis Obliterans; Bronchiolitis; Bronchitis; Bronchial Diseases; Respiratory Tract Diseases; Lung Diseases, Obstructive; Lung Diseases

Study Officials

• Jamie Y Hur, D.O.

  National Heart, Lung, and Blood Institute (NHLBI)

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: NIH
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 19, 2022
• First Posted: August 22, 2022
• Study Start: November 7, 2025
• Primary Completion: November 7, 2025
• Study Completion: November 7, 2025
• Last Updated: November 10, 2025

Record last verified: 2025-11

Locations

US (1)