All patients treated with ATIR101 will be followed up until 12 months after the HSCT. Assessments will be performed at weekly visits from the day of the first ATIR101 infusion (Week 4) until 6 weeks after the second ATIR101 infusion (Week 16), at monthly visits from 4 until 6 months after the HSCT, and every 3 months from 6 until 12 months after the HSCT.