The efficacy and safety of fostamatinib in adult patients with persistent/chronic immune thrombocytopenia (p/c ITP) were demonstrated in the FIT-1/FIT-2 trials. This retrospective, multicentre observational study evaluated real-world outcomes in consecutive p/c ITP patients treated with fostamatinib in Italy. The primary end-point, serving as a surrogate for both efficacy and safety, was the proportion of patients receiving fostamatinib for at least 6 months. Ninety-five patients were enrolled across 20 Italian centres, 59% female, median age 64 years (range 21–86). The median time from ITP diagnosis to fostamatinib initiation was 7.7 years; the median number of prior therapies was 4, including 54% of patients who received more than one thrombopoietin receptor agonist (TPO-RA) and 23% who underwent splenectomy. The overall response rate was 73%, with 32% complete responses. Most patients (74%) achieved a response within the first month. Concerning the primary end-point, 45% of patients received fostamatinib for 6 months; the median treatment duration was 7.3 months. The main cause of discontinuation was treatment failure (43%). Fifty-nine adverse events were reported in 38 patients, mostly grade 1–2, leading to fostamatinib discontinuation in 8% of patients. This real-world data confirm fostamatinib as an effective and safe option in relapsed/refractory ITP.
