Survival after stem-cell transplant in pediatric and young-adult patients with relapsed and refractory B-cell acute lymphoblastic leukemia

Abstract

Objective: Allogeneic stem-cell transplant (allo-SCT) is the standard of care for pediatric patients with acute lymphoblastic leukemia (ALL) who relapse after frontline chemotherapy; however, for patients who relapse after allo-SCT, outcomes are very poor. Few studies have examined overall survival in this patient population, particularly in patients who received a second allo-SCT.

Methods: This was a retrospective analysis using data from the Center for International Blood and Marrow Transplant Research (CIBMTR) registry. The study population included patients aged 3 to 21 years who were diagnosed with B-ALL and underwent their first allo-SCT between 2009 and 2013. The primary endpoint was the time from the date of posttransplant relapse to the date of death due to any reason.

Results: Outcomes in 1349 pediatric and young-adult patients were included in this analysis. The Kaplan–Meier estimated probability of survival at 3 years after first allo-SCT was 63.1% (95% CI, 60.2%–65.8%). Overall, 29.2% of patients relapsed after first allo-SCT and had a median survival of 7.4 months (95% CI, 6.0–9.6 months). Twenty-five patients in the analysis developed secondary malignancies, most of which were lymphoproliferative disorders.

Conclusions: Survival rates are low in pediatric and young-adult patients who relapse after first and second allo-SCT, and new therapies are needed to improve outcomes in this population. This data can be used as a historical comparison for single-arm trials of novel therapies for this patient population, including chimeric antigen receptor T-cell therapy.

Keywords:

• Acute lymphoblastic leukemia
• pediatric
• allogeneic stem-cell transplant
• survival

Transparency

Declaration of funding

This analysis was funded by Novartis Pharmaceuticals Corporation.

Author contributions: All authors contributed to study design and data collection and interpretation. All authors were involved in writing the manuscript and approved the final version.

Declaration of financial/other relationships

A.C. has disclosed that he was an employee of Novartis Farma (Italy) at the time of data analysis and manuscript preparation. J.Z. and C.K. have disclosed that they are employees and stock shareholders of Novartis Pharmaceuticals Corporation.

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

Acknowledgements

We thank John Togneri, PhD (ArticulateScience LLC, Hamilton, NJ), for medical editorial assistance. Financial support for medical editorial assistance was provided by Novartis Pharmaceuticals Corporation.