Background
Phase III, randomized clinical trial (PINES). 118 pediatric patients aged 1–<18 years with newly diagnosed primary ITP (platelet count <30×10⁹/L) requiring pharmacological treatment. Excluded: severe bleeding requiring rapid platelet increase. 23 centers in the Pediatric ITP Consortium of North America (ICON). Eltrombopag is a TPO-RA approved for chronic pediatric ITP but not studied in the newly diagnosed phase. Trial stopped early after prespecified interim analysis met efficacy boundary.
Interventions and follow up
Arm A: Eltrombopag (weight/age-based oral dosing) (n=78; 71 evaluable)
Arm B: Standard therapy (investigator choice: glucocorticoids, IVIG, or anti-D immunoglobulin) (n=40; 37 evaluable)
Primary endpoint: Sustained platelet response (≥3 of 4 platelet counts >50×10⁹/L at weeks 6–12 without rescue treatment)
mFollow up: Through week 12
Arm B: Standard therapy (investigator choice: glucocorticoids, IVIG, or anti-D immunoglobulin) (n=40; 37 evaluable)
Primary endpoint: Sustained platelet response (≥3 of 4 platelet counts >50×10⁹/L at weeks 6–12 without rescue treatment)
mFollow up: Through week 12
Results
Sustained platelet response: 65% (46/71) vs 35% (13/37), difference 30%, 95% CI 11–49%, P=.002
Baseline treatment failure rate: 63% had prior observation/medical therapy failure before enrollment
Baseline treatment failure rate: 63% had prior observation/medical therapy failure before enrollment
Adverse events
Main adverse events: No between-group difference in number or type of adverse events. Eltrombopag well tolerated in newly diagnosed children. No thromboembolic events or hepatotoxicity reported at this early stage.
Conclusions
Eltrombopag achieved significantly higher sustained platelet responses compared to standard first-line therapies in newly diagnosed pediatric ITP requiring treatment, supporting its use as an effective alternative in this setting.
Key Limitations
Key Limitations: Open-label in clinical practice (though randomized). Short follow-up (12 weeks) does not address long-term outcomes, spontaneous remission rates, or chronic disease development. Standard therapy arm was heterogeneous (glucocorticoids, IVIG, or anti-D) at investigator choice. Many enrolled patients (63%) had already failed initial observation/treatment — a self-selected persistent group. Sample size was modest (118 patients).
Clinical Context
Pediatric ITP management is shifting from the traditional "treat only if bleeding" approach toward biomarker-guided and patient-centered treatment decisions. Eltrombopag is already FDA-approved for chronic pediatric ITP (≥1 year age). PINES supports earlier use in newly diagnosed disease, particularly in patients who do not rapidly respond to initial therapy. This may reduce steroid exposure and hospitalization in children.
References
References: Shimano KA et al, JAMA 2025 (PINES)