Avatrombopag in thrombopoietin receptor agonist-naïve patients with immune thrombocytopenia: real-world treatment patterns and clinical outcomes from the REAL-AVA 3.0 study.

BACKGROUND: Avatrombopag (AVA) is a thrombopoietin receptor agonist (TPO-RA) approved for patients with immune thrombocytopenia (ITP), but real-world data is limited in TPO-RA-naïve patients. OBJECTIVES: To describe treatment patterns and outcomes in TPO-RA-naïve adult patients with primary ITP treated with AVA. METHODS: This retrospective chart review study included TPO-RA-naïve adults with primary ITP who initiated AVA on or after July 1, 2019, with ≥ 6 months of follow-up. Patients were followed from AVA initiation until the earliest of either last contact, death, or study end (January 20, 2025). Response was defined as achieving a platelet count (PC) ≥ 30, ≥ 50, or ≥ 100 × 109/L at least once. Response durability was calculated as the percentage of time on AVA with PCs above a response threshold among responders. PCs during or directly after rescue therapy were excluded from response assessments. RESULTS: Among 200 patients, 84.0% initiated AVA with baseline PCs < 30 × 109/L. Of these, 98.8% achieved PCs ≥ 30 × 109/L, 94.0% achieved PCs ≥ 50 × 109/L, and 74.4% achieved PCs ≥ 100 × 109/L. Median response durability was 93.2% for ≥ 30 × 109/L, 88.3% for ≥ 50 × 109/L, and 70.2% for ≥ 100 × 109/L. Most patients (66.5%) remained on their initial AVA dose. Median follow-up and treatment duration were 8.5 months (IQR, 7.0-13.5) and 8.0 months (IQR, 6.4-10.9), respectively. At last follow-up, 74.5% of patients remained on AVA. Discontinuation reasons included target PC achievement (51.0%), death (7.8%), and adverse events (2.0%). Most living patients who discontinued AVA (59.6%) received no further ITP treatment. CONCLUSION: AVA is an effective treatment option for TPO-RA-naïve patients with ITP, demonstrating a high real-world rate of sustained PC response.