Data from the PINES trial indicate that eltrombopag could achieve better outcomes than standard first-line therapies for children with newly diagnosed immune thrombocytopenia (ITP). The trial's findings, presented at the 66th American Society of Hematology (ASH) Annual Meeting and Exposition, suggest that eltrombopag was associated with a significantly greater rate of a durable response in the absence of rescue treatments relative to standard first-line therapies, such as prednisone, intravenous immunoglobulin (IVIG), or anti-D globulin.
Kristin A. Shimano, MD, professor of pediatrics at the University of California, San Francisco Benioff Children’s Hospital, noted, “This is the first time in 30 years that a new drug is being tested for newly diagnosed pediatric ITP. Patients who received eltrombopag during the first three months of their ITP diagnosis had a more sustained platelet response than patients who were treated with standard therapies. That means during this time period, kids taking eltrombopag were also likely to have a lower risk of having bleeding events.”
Trial Design and Patient Population
The PINES trial, launched four years after the FDA approval of eltrombopag in adults and children with chronic ITP in 2015, was conducted by the ITP Consortium of North America to assess the safety and efficacy of eltrombopag as a first-line therapy in pediatric ITP. This prospective, open-label, randomized trial took place at 23 medical centers and enrolled 118 patients diagnosed with ITP less than 3 months prior to enrollment who required pharmacologic treatment, according to their treating hematologist.
The study participants were randomized in a 2:1 ratio, stratified by age and prior treatment status, to receive either eltrombopag or standard of care. The primary outcome was a sustained platelet response at 12 weeks, defined as having 3 or 4 platelet counts higher than 50 x 109/L during weeks 6 to 12 without additional treatment.
Key Findings
The primary endpoint analysis revealed that 65% of patients in the eltrombopag arm achieved a platelet response, compared to 33% in the standard of care arm (P = .0007). Further analysis indicated that 19% of the eltrombopag arm required rescue therapy, while 46% of the standard of care arm needed it (P = .002).
Impact on Quality of Life
When assessing changes in quality of life, the mean absolute change from baseline in parent-proxy reported KIDS ITP Tool scores appeared to favor eltrombopag relative to standard of care at 1 week (P = .45), 4 weeks (P = .24), and 12 weeks (P = .14). Investigators noted that these differences were consistent with a clinically meaningful improvement in quality of life at all time points in both arms.
Clinical Implications
According to Shimano, “Eltrombopag could certainly be added to the medication choices hematologists consider as they are making treatment decisions with families, and it is an option that could potentially raise platelets for a more sustained period in children with ITP in the newly diagnosed period, which is one of the most difficult times for patients with regard to the impact of the disease on bleeding symptoms and quality of life.”
While eltrombopag has been approved for children with chronic ITP, this study aimed to evaluate its efficacy in newly diagnosed pediatric ITP compared with standard therapy (intravenous immunoglobulin, prednisone, or anti-D immunoglobulin).
