Evaluating fostamatinib disodium as a treatment option for immune thrombocytopenia in adult patients

ABSTRACT

Introduction

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by increased platelet destruction and decreased platelet production, leading to thrombocytopenia with or without bleeding manifestations. The majority of patients experiencing treatment need will eventually need secondary treatment following first-line therapy with steroids. In 2018, the oral spleen tyrosine kinase inhibitor fostamatinib received US Food and Drug Administration approval for ITP patients with an insufficient response to a previous treatment.

Areas covered

This review outlines pharmacological characteristics of fostamatinib and provides an overview of its efficacy and safety results in phase II and III trials, followed by the expert opinion of the authors.

Expert opinion

Increasing knowledge on the role of different players and mechanisms in the pathophysiology of autoimmune disorders, in general, and of ITP, in particular, has led to the development of several new treatment options, as illustrated by the introduction of fostamatinib in the treatment of ITP. However, lacking direct comparison with other recent treatment options (in particular, thrombopoietin receptor agonists), its use should be evaluated critically taking into account the unique toxicity and potential drug-drug interaction profile.

KEYWORDS:

• Fostamatinib
• spleen tyrosine kinase inhibitor
• ITP
• immune thrombocytopenia

Declaration of interest

D Dierickx has received consultancy fees from Swedish Orphan Biovitrum (Sobi), Amgen Inc, Roche and Novartis. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

One referee declares that they serve on advisory boards for Oncopeptides, AstraZeneca, Janssen Pharmaceuticals, and Pfizer Inc. Peer reviewers of this manuscript have no other relevant financial relationships or otherwise to disclose.