Haploidentical transplants for patients with relapse after the first allograft

Relapse after allogeneic hematopoietic stem‐cell transplantation (AHSCT) is associated with very poor outcomes. A second transplant offers the possibility of long‐term disease control. We analyzed outcomes with haploidentical donors for second allograft at our institution. All consecutive patients with hematological malignancies (N = 29) who relapsed after AHSCT and underwent a haploidentical transplant (haploSCT) as second transplant between February 2009 and October 2018 were included. Median age was 36 years (interquartile range (IQR) 24‐60); 83% of patients had high/very high disease risk index; 61% of AML/MDS patients had high‐risk cytogenetics; and only 24% were in complete remission at transplant. With a median follow‐up of 46.9 months, the 3‐year relapse, non‐relapse mortality (NRM), progression‐free survival (PFS) and overall survival (OS) were 30%, 39%, 31% and 40%, respectively. In multivariable analysis (MVA), comorbidity index (HCT‐CI) and detectable donor‐specific anti‐HLA antibodies (DSA) prior to second transplant were significantly associated with worse outcomes. Patients with HCT‐CI