Target population
The target population for this prospective study comprised children and
adolescents referred to our institution with relapsed/refractory (r/r)
AL (ALL or AML including sAML), who were aged > 1 and ≤ 21
years at the time of enrollment. For both ALL and AML, refractoriness
was defined as chemoresistant isolated or combined bone marrow relapse,
relapse > 6 months after allogeneic HSCT, or primary
induction failure. Patients relapsing after allogeneic HSCT could be
recruited directly. Patients relapsing after conventional treatment were
to have at least one failed remission induction attempt before
enrollment. Disease status was mandatory for inclusion and was assessed
by both morphological examination and immunophenotyping prior
enrollment. The following additional eligibility criteria were necessary
for enrollment: cardiac output SF ≥ 25%; adequate renal function
indicated by calculated creatinine clearance ≥ 90 ml/min/1.73
m2 (calculated by the Schwartz formula for estimated
glomerular filtration rate [GFR]); adequate liver function indicated
by serum bilirubin ≤ 1.5 × upper limit of normal (ULN); aspartate
transaminase/alanine transaminase; alkaline phosphatase ≤ 2.5× ULN;
Lansky or Karnofsky performance status of ≥ 70%; a suitable adult
haploidentical family member available for stem cell donation and
fulfilling institutional criteria for blood and marrow donation.
Informed consent and assent (adjusted to different age categories) from
patients/parents were required for enrollment. The study was approved by
the Swedish Ethical Review Authority (File no. 2009/83) and registered
at clinicval.trials.gov (NCT01025778) and the European Union Drug
Regulating Authorities Clinical Trials Database (EudraCT number
2009-012437-30), and it was conducted in accordance with the principles
of the Helsinki Declaration.