Abstract

BACKGROUND

Clinical data on hetrombopag, a novel thrombopoietin receptor agonist (TPO-RA) developed in China, remain limited for the treatment of immune thrombocytopenia (ITP). This retrospective study aimed to investigate the efficacy and safety of hetrombopag for ITP patients in the real-world setting.

METHODS

Patients with ITP received hetrombopag monotherapy at an initial dose of 2.5 mg or 5.0 mg once daily. The primary endpoint was the proportion of responders whose platelet count ≥ 50 × 10 9 /L, which were assessed at week 4, 8 and 12 after treatment. The secondary endpoint was the safety profile of hetrombopag.

RESULTS

A total of 50 ITP patients were enrolled. The median time to response was 7 days; the mean platelet count increased from 16 × 10⁹/L at baseline to 104 × 10⁹/L at week 12; the response rate was 71% at week 12. The 5 mg/d group showed significantly better efficacy as early as week 2 compared with the 2.5 mg/d group (P < 0.05). Among 15 nonresponders in the 2.5 mg group, 11 patients were switched to the 5 mg group, and 6 of them then achieved response. The clinical response was reached in 7 of 8 ITP patients switching from eltrombopag to hetrombopag. There was no difference in the overall response rate between patients receiving hetrombopag as a second-line therapy and later-line therapies (P = 0.951). No serious adverse events were observed. In addition, the total number of megakaryocytes in the bone marrow was positively associated with treatment efficacy at week 4 (P = 0.001).

CONCLUSIONS

Hetrombopag was effective and safe in the real-world treatment of ITP. An initial dosage of hetrombopag 5 mg/d and a higher megakaryocyte count in bone marrow may predict better therapeutic efficacy.

MeSH

Megakaryocytes, Platelet Count, Bone Marrow, Safety, Cohort Studies, Clinical Medicine, Therapeutics, Blood Platelets, Thrombocytopenia, Purpura, Thrombocytopenic, Idiopathic