Hetrombopag for patients with persistent primary immune thrombocytopenia: a post hoc analysis of a multicenter,...

Hetrombopag has been approved for chronic ITP (duration >12 months). However, its efficacy and safety in persistent ITP (duration 3-12 months) remain unexplored.

This post-hoc analysis aimed to evaluate the efficacy and safety of hetrombopag in persistent ITP patients and compare outcomes with chronic ITP and overall ITP patients, based on existing clinical data.

Data were derived from a registration phase Ⅲ trial (NCT03222843), which included a 10-week randomized, double-blind, placebo-controlled treatment period (initial dose: hetrombopag 2.5 mg as HETROM-2.5 group, hetrombopag 5.0 mg as HETROM-5.0 group, or placebo once daily), a 14-week open-label treatment period, a dose tapering to withdrawal period and a 24-week single-arm extension period. The primary endpoint was the proportion of responders (a platelet count of ≥ 50 × 10⁹/L) after 8 weeks of treatments.

Of 395 who completed the double-blinded treatment, 80 patients had persistent ITP. The proportion of patients with persistent ITP who achieved primary endpoint was 68.8% in the HETROM-2.5 group and 74.3% in the HETROM-5.0 group, significantly higher than 7.7% in the placebo group. Hetrombopag also demonstrated other therapeutic benefits over placebo including reduced bleeding risk and rescue therapy need. Similar efficacy results were observed in both the chronic ITP and the overall ITP population. Furthermore, hetrombopag manifested favorable safety profile in patients with persistent ITP, and safety outcomes were comparable with those in chronic and overall ITP populations.

Hetrombopag showed favorable safe and efficacy profile in patients with persistent ITP, aligning with results observed in patients with chronic ITP and overall ITP.