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

> **NCT05509582** · PHASE2 · WITHDRAWN · sponsor: **National Heart, Lung, and Blood Institute (NHLBI)**

## Conditions studied

- Immune Mediated Anemia
- Immune Mediated Thrombocytopenia
- Chronic GVHD

## Interventions

- **DRUG:** fostamatinib

## Key facts

- **NCT ID:** NCT05509582
- **Lead sponsor:** National Heart, Lung, and Blood Institute (NHLBI)
- **Sponsor class:** NIH
- **Phase:** PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** WITHDRAWN
- **Start date:** 2025-11-07
- **Primary completion:** 2025-11-07
- **Final completion:** 2025-11-07
- **Target enrollment:** 0 (ACTUAL)
- **Why stopped:** No responders in parent protocol 000758; this follow-on protocol not activated and PI leaving NIH
- **Last updated:** 2025-11-10


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05509582

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05509582, "Extension Study (Extended Access) of Syk-inhibition Using Fostamatinib to Treat Posttransplant Immune-mediated Cytopenias". Retrieved via AI Analytics 2026-07-16 from https://api.ai-analytics.org/clinical/NCT05509582. Licensed CC0.

---

*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*