Rapid early hematological response in a newly diagnosed patient with very severe aplastic anemia: a case report of high-dose romiplostim, hetrombopag and IST combination therapy.

BACKGROUND

Very severe aplastic anemia (VSAA) is a life-threatening bone marrow failure syndrome. For patients ineligible for allogeneic hematopoietic stem cell transplantation (HSCT), effective treatments that induce rapid responses remain limited. This case report describes a young VSAA patient who achieved an exceptionally rapid trilineage response to first-line therapy with high-dose romiplostim (ROMI), hetrombopag, and standard immunosuppressive therapy (IST).

CASE PRESENTATION: A 16-years-old male with newly diagnosed VSAA (neutrophils 0.13 × 109/L, platelets 11 × 109/L) declined HSCT due to fertility concerns. He received ROMI (10 μg/kg weekly, titrated to 20 μg/kg), hetrombopag (7.5 mg daily), and IST (rabbit ATG 3 mg/kg/day for 5 days; cyclosporine 3 mg/kg/day). A partial trilineage response was achieved by week 9, with transfusion independence for red cells and platelets by week 12. By week 22, he achieved complete remission. After 7 months of follow-up, he remained in complete remission (neutrophils 2.2 × 109/L, hemoglobin 127 g/L, platelets 160 × 109/L). ROMI has been gradually tapered and is currently administered at 10 μg/kg per month. Throughout the treatment period, the patient experienced only grade 1-2 nausea and muscle spasms.

CONCLUSION

The combination of high-dose ROMI, hetrombopag, and IST induced a rapid response in this young VSAA patient who refused HSCT. This dual TPO-RA regimen warrants further investigation as a potential first-line option for HSCT-ineligible VSAA patients.