Significant improvement of child physical and emotional functioning after familial haploidentical stem cell transplant

Neurocognitive outcome in children with sickle cell disease after myeloimmunoablative conditioning and haploidentical hematopoietic stem cell transplantation: a non-randomized clinical trial

Background

Due to the risk of cerebral vascular injury, children and adolescents with high-risk sickle cell disease (SCD) experience neurocognitive decline over time. Haploidentical stem cell transplantation (HISCT) from human leukocyte antigen-matched sibling donors may slow or stop progression of neurocognitive changes.

Objectives

The study is to determine if HISCT can ameliorate SCD-associated neurocognitive changes and prevent neurocognitive progression, determine which specific areas of neurocognitive functioning are particularly vulnerable to SCD, and determine if there are age-related differences in neurocognitive functioning over time.

Methods

We performed neurocognitive and neuroimaging in SCD recipients following HISCT. Children and adolescents with high-risk SCD who received parental HISCT utilizing CD34+ enrichment and mononuclear cell (T-cell) addback following myeloimmunoablative conditioning received cognitive evaluations and neuroimaging at three time points: pre-transplant, 1 and 2 years post-transplant.

Results

Nineteen participants (13.1 ± 1.2 years [3.3-20.0]) received HISCT. At 2 years post-transplant, neuroimaging and cognitive function were stable. Regarding age-related differences pre-transplantation, older children (≥13 years) had already experienced significant decreases in language functioning (p < 0.023), verbal intelligence quotient (p < 0.05), non-verbal intelligence quotient (p < 0.006), and processing speed (p < 0.05), but normalized post-HISCT in all categories.

Conclusion

Thus, HISCT has the potential to ameliorate SCD-associated neurocognitive changes and prevent neurocognitive progression. Further studies are required to determine if neurocognitive performance remains stable beyond 2 years post-HISCT.Clinical trial registration: The study was conducted under an investigator IND (14359) (MSC) and registered at clinicaltrials.gov (NCT01461837).

Incidence and risk factors of pain crisis after hematopoietic cell transplantation for sickle cell disease

ABSTRACT

Vaso-occlusive episodes (VOC) or pain crises are the most common indications for hematopoietic cell transplantation (HCT) for sickle cell disease (SCD). Elimination of pain crisis after HCT is an important patient-centered outcome and may improve understanding of the natural history of pain syndromes in SCD. We examined deidentified records of 763 patients followed-up for a median of 36.7 months (range, 0.3-168.6 months), with 69.6% patient's age <18 years at HCT, 83.3% patient's Karnofsky-Lansky performance score (KPS) ≥90, overall survival 92.9%, event-free survival 72.4%, graft failure (GF) 22.4%, AGVHD 21.4%, CGVHD 27%, and pain crisis 8.65%. On unadjusted logistic regression, increased risk of pain crisis after HCT was observed in patient's aged >10 years at HCT (range, 11-17 years; OR, 9.43; 95% CI, 3.20-27.79; P < .0001), in age ≥18 years (OR, 16.62; 95% CI, 5.85-47.16; P < .0001), in those with history of pain crisis 2 years before HCT (OR, 13.16; 95% CI, 4.08-42.42; P < .0001), alternate donors (haploidentical [OR, 4.80; 95% CI, 2.48-9.31; P < .0001], unrelated matched [OR, 2.71; 95% CI, 1.23-5.97; P = .0132], and mismatched unrelated [OR, 3.19; 95% CI, 1.44-7.05; P = .0041], and those with GF (n = 41 [5.37%]; OR, 7.15; 95% CI, 4.20-12.18; P < .0001). Pain crisis was less frequent with KPS of ≥90 (OR, 0.31; 95% CI, 0.18-0.55; P < .0001). Multivariable logistic regression models confirmed age at HCT, KPS, graft type, donor type, history of VOC 2 years before HCT, and GF as independent predictors of pain crisis after HCT and generated predictive models and nomograms for pain crisis after HCT for SCD, which can support shared decision making.

Excellent outcome of stem cell transplantation for sickle cell disease

Many sickle cell disease (SCD) patients lack matched family donors (MFD) or matched unrelated donors (MUD), implying haploidentical donors (MMFD) as a logical donor choice. We used a reduced toxicity protocol for all donor types. We included 31 patients (2-22 years) with MFD (n = 15), MMFD (10), or MUD (6) HSCT and conditioning with alemtuzumab/ATG, thiotepa, fludarabine and treosulfan, and post-transplant cyclophosphamide for MMFD. After the initial six patients, treosulfan was replaced by targeted busulfan (AUC 65-75 ng*h/ml). After a median follow-up of 26 months (6-123), all patients are alive and off immunosuppression. Two MMFD patients experienced secondary graft failure with recurrence of SCD, both after treosulfan conditioning. Neither acute GVHD ≥ °III nor moderate/severe chronic GVHD was observed. The disease-free, severe GVHD-free survival was 100%, 100%, and 80% in the MFD, MUD, and MMFD groups, respectively (p = 0.106). There was a higher rate of virus reactivation in MMFD (100%) and MUD (83%) compared to MFD (40%; p = 0.005), but not of viral disease (20% vs 33% vs 13%; p = 0.576). Six patients had treosulfan-based conditioning, two of whom experienced graft failure (33%), compared to 0/25 (0%) after busulfan-based conditioning (p = 0.032). Donor chimerism was ≥ 80% in 28/31 patients (90%) at last follow-up. Reduced toxicity myeloablative conditioning resulted in excellent overall survival, negligible GVHD, and low toxicity among all donor groups in pediatric and young adult patients with SCD.