OBJECTIVES: Diverse treatment strategies can be utilized for patients living with primary immune thrombocytopenia (ITP), a rare autoimmune platelet disorder. The objective of this study was to assess common treatment patterns in the chronic phase among adults with primary ITP using a United States (US) claims database.

METHODS: Using a comprehensive US-based administrative claims database (Komodo Health closed claims, January 2015-March 2023), adults aged ≥18 years with primary chronic ITP were identified as follows: (1) ≥2 outpatient claims separated by 30-365 days or ≥1 inpatient claim associated with primary ITP between Jan 2016 and Mar 2021, (2) ≥3 years of continuous enrollment with no ITP diagnoses 1 year prior to first primary ITP claim, (3) absence of diagnostic or treatment codes associated with secondary ITP, and (4) ≥1 primary ITP claim during the chronic phase (365-730 days following their first diagnosis). ITP treatments used during the chronic phase were assessed. Utilizing time sequence-based cluster analyses, patients were clustered based on their treatment patterns in the chronic phase.

RESULTS: Among 7576 patients identified, 3499 (46%) received ITP treatment during the chronic phase. The most common ITP treatments used in the chronic phase were steroids (oral: n=2262/3499, 65%; intravenous: n=1692/3499, 48%) and thrombopoietin receptor agonists (TPOs, n=564/3499, 16%). Among the 3499 patients receiving treatment, 4 chronic-phase treatment pattern-based clusters were identified: (1) intermittently treated with steroids (n=2907, 83%), (2) continuously treated with TPOs (n=259, 7%), (3) continuously treated with steroids (n=194, 6%), and (4) continuously treated with non-steroids (n=139, 4%).

CONCLUSIONS: This research characterized 4 distinct treatment clusters in primary chronic ITP among adult patients in the US. Future studies should be conducted to better understand the impact of different treatment strategies on patient burden in primary chronic ITP.