Impact of treosulfan exposure on clinical outcome after allogeneic stem cell transplantation in children: A substudy of 2 phase 2 trials.

Aims Methods Results Conclusion Allogeneic haematopoietic stem cell transplantation (allo‐HSCT) is a vital treatment for various paediatric malignant and nonmalignant diseases. The conditioning treatment before allo‐HSCT is crucial for successful engraftment. Treosulfan, a cytotoxic prodrug, has gained popularity due to its lower toxicity compared to traditional alkylating agents used for conditioning treatment.We investigated the relationship between pharmacokinetics and pharmacodynamics of treosulfan in paediatric patients, in a substudy pooling from 2 multicentre phase 2 clinical trials. A total of 83 children with malignant and nonmalignant diseases received treosulfan‐based conditioning. Treosulfan exposure and its relationship with clinical outcomes, including survival, graft failure and graft‐<italic>vs</italic>.‐host disease, were investigated.Our findings reveal no significant association between treosulfan exposure and the key clinical outcomes or toxicity (<italic>P</italic>‐values between .22 and .99), if the dosing is based on the approved product information.These findings suggest that treosulfan exposure after standardized body surface area‐based dosing is appropriate in paediatric allo‐HSCT. [ABSTRACT FROM AUTHOR]