PB0721 - Case Report: Clinical manifestations and therapeutic options following rhTPO-induced neutralizing antibody production in a child with immune thrombocytopenia

Monday, June 24, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

NW

Nan Wang, Master student

Department of Pharmacy
Beijing Children’s Hospital, Capital Medical University,
Beijing, Beijing, China (People's Republic)

Co-Author(s)

Zhifa Wang, PhD

Resident physician
Department II of Hematology Center, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, 100045, China
Beijing, Beijing, China (People's Republic)
SD

Shuyue Dong

Resident physician
Department II of Hematology Center, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, 100045, China
Beijing, Beijing, China (People's Republic)
Jingyao Ma, MD

attending physician
Hematology Department, National Center for Children’s Health, Beijing Children’s Hospital, Capital Medical University, Beijing 101300, China.
Beijing, Beijing, China (People's Republic)
XC

Xiaoling Cheng

Department of Pharmacy
Beijing Children’s Hospital, Capital Medical University,
Beijing, Beijing, China (People's Republic)
Runhui Wu, PhD, MD

Professor
Department of Hematology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, 100045, China
Beijing, Beijing, China (People's Republic)

Background: Recombinant human thrombopoietin (rhTPO) is commonly used to improve low platelet status in immune thrombocytopenia (ITP), as one protein product, even with a very low rate, there is still the possibility to produce neutralizing antibodies of thrombopoietin (TPO).

Aims: This article aims to describe the clinical symptoms and the treatment of rhtpo after it has produced antibodies.

Methods: We present a case report of a previous consultation with a pediatric patient.

Results: We described a 7-year-old boy with ITP and normal TPO levels who had previously received rhTPO for 2 weeks but showed persistent thrombocytopenia and was misdiagnosed as acquired amegakaryocytic thrombocytopenia (AATP) and ineffectively treated with cyclosporine A (CsA) in combination with avatrombopag (AVA). As suspicious the TPO neutralizing antibody development as re-test of TPO level is 0, the CD20+ deletion antibody drug rituximab (RTX) was prescribed and received efficacy.

Conclusion(s): rhTPO serves as one bio-protein drug and should be cautious with the development of neutralizing antibodies if the drug effect is lost. The antibody and/or TPO level tests should be done for the diagnosis, and the antibody eradication medication as an anti-CD20 antibody, RTX should be prescribed to delete these neutralizing antibodies to recover the TPO level to reattain the response of ITP treatment.