Avatrombopag in heavily pretreated chronic immune thrombocytopenia: a single center experience from Oman

Chronic immune thrombocytopenia (ITP) is characterized by persistent thrombocytopenia and bleeding risk, and a subset of patients remains refractory or relapses despite multiple lines of therapy. Avatrombopag is an oral thrombopoietin receptor agonist approved for adults with chronic ITP with insufficient response to prior treatment. We descrixbe a real-world single-center experience with avatrombopag in Oman.

We conducted a retrospective case series of consecutive adults with chronic primary ITP treated with avatrombopag at a tertiary care center in Muscat, Oman. Patients initiated avatrombopag between September 2023 and June 2025 and were followed through October 2025. Platelet counts, treatment patterns, transfusion requirements, corticosteroid use, rescue therapies, and adverse drug reactions (ADRs) were abstracted from electronic medical records.

Twelve heavily pretreated patients were included, with a median baseline platelet count of 14.5 × 10⁹/L (IQR 4.8-28.8). Eleven patients (91.7%) started avatrombopag at 20 mg once daily, and one patient (8.3%) started at 20 mg on alternate days; 66.7% required subsequent dose adjustment. Overall, 75.0% achieved platelet counts ≥ 50 × 10⁹/L at least once during follow-up, with a median platelet count of 160 × 10⁹/L at month 3 and 98 × 10⁹/L at the most recent assessment. Transfusion burden improved in 60% of patients with high baseline transfusion requirements. Steroid-sparing was observed in 83.3, and 66.7% were steroid-free during follow-up. ADRs occurred in 33.3% (primarily body pain and rash); no hepatotoxicity or treatment discontinuation due to ADRs was documented.

In chronic, heavily pretreated ITP, avatrombopag was associated with clinically meaningful platelet responses, substantial steroid-sparing, and an acceptable tolerability profile.