PARACHUTE is an acronym for Prospective Analysis of an Individualized Dosing Regimen of ATG (Thymoglobulin) in Children Undergoing HCT: redUcing Toxicity and Improving Efficacy). Rick Admiraal, pediatrician in training as a pediatric oncologist and researcher at the Máxima Center, says: ‘It is a clinical trial in which we treated children who received a stem cell transplant with a personalized dosage of anti-thymocyte globulin (ATG). With a new dose of this existing drug, we hoped to promote immune system recovery after transplantation. This is the first study worldwide in which fully personalized dosing of medication has been investigated. Using mathematical models, we calculated exactly how much ATG was needed for each patient for maximum effectiveness and the fewest possible side effects.'
Extraordinary result
Rick Admiraal: 'We show that children with personalized dosing of ATG have much better immune recovery, with 75% of the children in the study versus 51% with standard dosing. The personalized dosage is often lower than a child had received standard. However, we did not find a reduced effect of ATG, in fact, graft-versus-host-disease and rejection occurred at the same rate. Survival for children in the study is 81% after three years of follow-up. At standard doses, it is 66%. This, partly due to short follow-up, is not statistically significant, but it is hopeful and special! In such a complex and long-term treatment as a stem cell transplant, the dosage of a particular drug like this is so important.' All children at the Máxima Center receive the personalized dose since the study.
Follow-up research
Rick: 'In the coming years, I want to focus on CAR T-therapy, in which we want to use modeling to better understand why this therapy works well in some patients and less well in others. The results of the PARACHUTE study inspire me for future research in pharmacology and in pediatric oncology.'