Multicenter, real-world observational study of AVA therapy following ELT/HET switching in Chinese children with persistent/chronic primary ITP

Abstract

Avatrombopag (AVA), a second-generation thrombopoietin receptor agonist (TPO-RA), has demonstrated efficacy in pediatric persistent/chronic immune thrombocytopenia (ITP). However, critical evidence gaps persist regarding treatment-switching strategies between TPO-RAs, particularly when transitioning from eltrombopag (ELT) or hetrombopag (HET) to AVA. This multicenter cohort study evaluated 55 pediatric ITP patients unresponsive to or relapsing after ELT (n = 46) or HET (n = 9) who underwent AVA switch therapy. Outcomes included platelet response (≥ 30 × 10⁹/L without rescue therapy), bleeding events, concomitant medication reduction, and safety. Sustained response rates reached 48.4% (ELT-to-AVA) and 33.3% (HET-to-AVA), with median response durations of 10 and 7 days respectively. Platelet elevation during AVA treatment was resolved with dosage changes or discontinuation. AVA significantly reduced bleeding, ITP medications, and rescue therapy, with side effects such as gastrointestinal symptoms, headaches, and fatigue (grades 1–2). AVA demonstrates potential as a safe and effective bridging therapy for TPO-RA refractory pediatric ITP, offering hematological stabilization while reducing treatment burden. These findings address current evidence deficiencies in TPO-RA switching protocols.