Cyclophosphamide and horse anti-thymocyte globulin versus fludarabine, reduced cyclophosphamide and rabbit anti-thymocyte globulin conditioning regimen for allogeneic hematopoietic stem cell transplantation from matched sibling donors in patients with acquired aplastic anemia

ABSTRACT

Background

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment for acquired aplastic anemia (acquired AA) in young patients. The objective of the study was to compare patient outcomes after Cyclophosphamide and horse antithymocyte globulin (Cy-hATG) versus Fludarabine-cyclophosphamide and rabbit ATG (Flu-Cy-rATG) as part of conditioning regimen in allo-HSCT for acquired AA.

Research design and methods

Descriptive retrospective study conducted on patients with acquired AA who received allo-HSCT from HLA-matched sibling donors between January 2008 and August 2022 after conditioning regimen with Cy-hATG or Flu-Cy-rATG.

Results

A total of 121 patients were enrolled. Cumulative incidence of graft failure was 11.2% in Cy-hATG and 5.3% Flu-Cy-rATG group. There were no significant differences between the two groups in terms of acute GVHD, chronic GVHD, and transplant related mortality. Flu-Cy-rATG group was associated with significantly higher CMV and EBV reactivation(s) compared to Cy-hATG group (p = 0.008 and 0.035, respectively). After a median follow-up of 58 months, estimated overall survival, event-free survival, and graft rejection-free survival were not statistically different between the two groups.

Conclusions

In high-risk population, Flu-Cy-rATG is associated with comparable outcomes to Cy-hATG in allo-HSCT from MSD. However, it seems to be associated with significant risk of viral infections.

KEYWORDS:

• Aplastic anemia
• conditioning regimen
• allogeneic hematopoietic stem cell transplantation
• graft failure
• survival

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

NB Abdeljelil, IB Yaiche, R Ouerghi, L Torjemane, D Belloumi, I Turki, S Mekni, RY Kanoun, TB Othman, and S Ladeb have substantially contributed to the conception and design of the review article and interpreting the relevant literature and have been involved in writing the review article or revising it for intellectual content.

Ethics

This study was approved by the ethics committee of Centre National de Greffe de Moelle Osseuse, Université de Tunis El Manar Tunis, Tunisia (reference: CNGMOEC-0124). Informed consent for the allo-HSCT was obtained from all the patients or legal guardians, and all donors.

Previous presentations

This study had been previously presented as an ‘Oral presentation at the 49th Annual Meeting of the EBMT which held in Paris, France from the 23rd to the 26th of April 2023: Wednesday, April 26, 12:30–13:45 OS16 Oral Session 16 | Novel and old agents in HSCT.’

Additional information

Funding

This paper was not funded.