Comparison of anti-thymocyte globulin-based immunosuppressive therapy and allogeneic hematopoietic stem cell transplantation in patients with transfusion-dependent non-severe aplastic anaemia: a retrospective study from a single centre

Abstract

Objectives

The selection and timing of anti-thymocyte globulin (ATG)-based immunosuppressive therapy (IST) or allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with transfusion-dependent non-severe aplastic anemia (TD-NSAA) pose significant clinical challenges. This study aims to compare the efficacy and long-term outcomes of the two treatments in TD-NSAA.

Methods

Patients who underwent ATG-based IST or allo-HSCT between July 2011 and December 2019 were reviewed. We gathered their clinical information, treatment response, survival data, and subsequently analysed the associated risk factors.

Results

A total of 97 TD-NSAA patients were reviewed, and 55 patients who underwent either ATG-based IST (n = 27) or allo-HSCT (n = 28) were enrolled. We observed a significant disparity in the 12-month overall response rate (ORR) (48.1% in IST vs 78.6% in HSCT, p < 0.05), but not in five-year overall survival (OS) and event-free survival (EFS). Multivariate Cox regression analysis identified the transfusion of ≥78.75 units of red blood cells (RBCs) as the sole independent risk factor for OS (HR: 17.04, p = 0.039) in the IST group. For the HSCT group, disease duration (DD) ≥20 months and transfusion of ≥78.75 units of RBCs predicted an adverse EFS. Frontline IST exhibited superior 12-month ORR (68.8% vs 18.2%, p = 0.018) and five-year EFS when compared to non-frontline. Patients with a DD ranging from 6 to 20 months displayed a better EFS (p = 0.016) in HSCT group than those in the ATG-based IST group.

Conclusions

Prior treatment history, disease duration, and serum ferritin levels should be carefully weighed when making the choice between ATG-based IST and allo-HSCT for TD-NSAA.

KEY MESSAGES

1. The selection and timing of anti-thymocyte globulin (ATG)-based immunosuppressive therapy (IST) or allogeneic hematopoietic stem cell transplantation (allo-HSCT) present notable clinical challenges for individuals with transfusion-dependent non-severe aplastic anaemia (TD-NSAA).

2. In terms of treatment outcomes, allo-HSCT exhibited a higher 12-month overall response rate (ORR) in comparison to ATG-based IST among TD-NSAA patients. Nevertheless, comparable rates of 5-year overall survival (OS) and event-free survival (EFS) were observed between the two therapeutic approaches.

3. Several factors warrant consideration when deliberating between ATG-based IST and allo-HSCT for TD-NSAA. These factors include the patient’s prior treatment history, disease duration, number of packed red cell transfusions received, and serum ferritin levels.

Keywords:

• Hematopoietic stem cell transplantation
• immunosuppressive therapy
• transfusion-dependent
• non-severe aplastic anaemia

Acknowledgements

We thank all the patients who gave consent to disclose their medical records and answered our review calls.

Author contributions

D.W. and B.Y. conceived and designed the study. Y. L, Q. L., Y.S., Y.H., J.D., and Y.H. assisted in the acquisition of data. Y.L, Q. L., D.W., S.L., Y.C., and Y.S. analyzed and interpreted the data. Y.L., Y.S., Q.L., and D.W. wrote, reviewed, and revised the manuscript. W.L., Q.Y., H.H., S.D., H.Z., Z.H., S.L., Y.S., Y.Z. and J.S. took care and followed up the patients. All authors contributed toward data analysis, drafting, and critically revising the paper and agree to be accountable for all aspects of the work.

Ethics approval and consent to participate

This study was approved by the ethical committee of the First Affiliated Hospital of Zhejiang Chinese Medical University (NO.2022-KL-159-02). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability

The data used and/or analysed during the current study are available from the corresponding author upon a reasonable request.

Additional information

Funding

The present study was supported by National Natural Science Foundation of China under Grant No. 82174138 and No. 82304937; Zhejiang Scientific Research Fund of Traditional Chinese Medicine under Grant No. 2020ZB085; Health Technology Plan of Zhejiang Province under Grant No. 2022RC216 and No. 2021KY822; Project of Zhejiang Famous Traditional Chinese Medicine Expert Inheritance Studio Construction under Grant No. GZS2021022.