Search

Graphical abstract:

Graft versus tumor relies on tumor-associated antigens (TAAs) that are presented to donor T cells via human leukocyte antigens (HLAs). The HLA evolutionary divergence (HED) between alleles of a single individual can dictate the ability to present TAAs. The impact of HED in haploidentical donor transplantation (HIDT) has not been studied. We studied the effect of HED on transplant outcomes following HIDT. We analyzed 322 consecutive recipient/donor pairs with a median follow-up of 57.2 months. Pairwise divergence of HLA class I and II showed that HLA-B, -DRB1, and -DQB1 contributing most to mean HED. The mean HED was class I 6.85 (HLA-A 7.08, -B 8.24, and -C 5.07), class II 8.58 (HLA-DRB1 10.97, -DQB1 10.06 and -DPB1 4.06). A high HED in class I mismatched recipient/donor haplotype (RD MM) was significant for worse DFS (HR 1.11, p= 0.020), and relapse (HR 1.11, p= 0.02). Also, a high HED in RD MM HLA-B haplotype had worse OS (HR 1.07, p= 0.02), DFS (HR 1.09, p= 0.002), higher relapse (HR 1.10, p= 0.003), and similar NRM to low HED. The multivariate analysis showed that high HED in RD MM HLA-B (≥7.8 vs <7.8) had worse DFS (HR 1.53, p= 0.01), higher relapse (HR 1.61, p= 0.024), and similar NRM and OS.

Steroid refractory acute graft-versus-host disease (SR aGvHD) is a major limitation of successful allogeneic hematopoietic stem cell transplantation (HSCT). Extracorporeal photopheresis (ECP) has been used to treat SR aGvHD effectively and with low treatment related toxicity. In this study, we retrospectively analyzed the outcomes of 103 Steroid Refractory aGvHD (SR aGvHD) patients to identify factors associated with improved outcomes including the use of ECP. A total of 79 patients received ECP as part of their SR aGVHD treatment compared to 24 patients who did not. Both groups had similar aGVHD grade and maximum organ stage at onset of aGVHD and treatment initiation. Patients in the group that received ECP had better OS (p= 0.01), DFS (p= 0.008), lower relapse (p= 0.05) and similar NRM compared to the group that did not receive ECP. Patients that received ECP treatment also had shorter hospital stays in the first 180 days after onset of SR aGvHD (20 vs. 38 days, p= 0.03). Multivariable analysis for OS indicated patient CMV status (CMV+ versus CMV–, HR 2.34, CI 1.16–4.69), regimen intensity (Myelo vs. non-Myeloablative, HR 0.39, CI 0.20–0.75), and the use of ECP (ECP vs. no ECP, HR 0.39, CI 0.20–0.75) were associated with OS. In summary, the use of ECP in the treatment of SR aGvHD results in improved overall survival secondary to lower relapse rates compared to other therapeutic modalities that do not incorporate ECP.

Due to perceived intolerance, many elderly AML patients do not receive therapy, and few are considered for hematopoietic cell transplantation (HCT). To better understand “real-world” outcomes, 323 consecutive AML patients ≥ 60 years referred from 2009 to 2017 were evaluated (median age 70 [60–88] years); favorable (fav) in 48 (15%), intermediate (int) in 112 (35%) and poor risk in 161 (50%). Remission induction therapy, either intensive chemotherapy (IC, n= 205) or hypomethylating agents (HMA, n= 57), was given to all but 61 (19%) patients. With median f/u of 34 months, 2-year overall survival (OS) for the whole cohort was 31%; 40 and 33% for IC- and HMA-treated vs. 0% for untreated patients. Early mortality was 14%. Remission (CR/CRi) was achieved in 60% of patients, with approximately half of these surviving 2 years. In transplant-eligible patients (60–75-year-old, int/poor risk, achieving remission), 54 (46%) of 118 received HCT. Transplanted patients had improved 2- and 3-year post-remission survival of 59% and 40% compared to 26% and 18% in similar patients not receiving HCT (HR = 0.59, 95% CI 0.37–0.93, p= 0.023). These results suggest that survival of elderly AML patients may be improved through a coordinated approach of remission induction therapy for most patients followed by HCT when feasible.

The number of HLA-haploidentical hematopoietic cell transplants continues to increase worldwide due to recent improvements in outcomes, allowing more patients with hematological malignancies and non-malignant disorders to benefit from this procedure and have a chance to cure their disease. Despite these encouraging results, questions remain as multiple donors are usually available for transplantation, and choosing the best HLA-haploidentical donor for transplantation remains a challenge. Several approaches to haploidentical transplantation have been developed over time and, based on the graft received, can be grouped as follows: T-cell depleted haploidentical transplants, either complete or partial, or with T-cell replete grafts, performed with post-transplant cyclophosphamide-based graft-versus-host disease (GVHD) prophylaxis, or G-CSF-primed bone marrow graft and enhanced GVHD prophylaxis. Carefully selecting the donor can help optimize transplant outcomes for recipients of haploidentical donor transplants. Variables usually considered in the donor selection include presence of donor-specific antibodies in the recipient, donor age, donor/recipient gender and ABO combinations, and immunogenic variables, such as natural killer cell alloreactivity or KIR haplotype. Here we provide a comprehensive review of available evidence for selecting haploidentical donors for transplantation, and summarize the recommendations from the European Society for Blood and Marrow Transplantation (EBMT) on donor selection for different transplant platforms.

Initial therapy of chronic GVHD (cGvHD) has not changed for over three decades, despite limited efficacy and long-term toxicity. We have previously shown in a small pilot study the feasibility of rituximab-based first-line therapy of cGVHD. To better assess safety and efficacy, we now evaluate 69 patients that received rituximab as part of their initial treatment. Median follow-up for surviving patients was 47 (11–81) months. Resolution of cGVHD occurred in 49 patients with median time to IST discontinuation of 349 (138–920) days. The cumulative incidence (CI) of cGHVD resolution was 41%, 69 and 77% at 1-, 2- and 3-years, respectively. No systemic corticosteroids were used in 27 patients, and 67% received ≤ 10 mg/kg cumulative exposure. Overall survival (OS) at 1-, 2- and 3-years following cGVHD diagnosis was 87, 79 and 77% respectively; corresponding rates of non-relapse mortality (NRM) were 10%, 16 and 19%. The probability of being alive and free of cGVHD at 1-, 2-, and 3-years was 36, 55, and 57% respectively. This study demonstrates the feasibility and efficacy of rituximab-based first-line cGVHD treatment. This approach demonstrates significant activity and avoids long courses of corticosteroids in most patients.

The original version of this Article contained a typographical error in the spelling of the author Marcelo Fernandez-Vina, which was incorrectly given as Marcelo Fernadez-Vina. This has now been corrected in the PDF and HTML versions of the Article.