We studied the impact of HLA mismatching on the outcome of 318 consecutive patients who received an unmanipulated haploidentical bone marrow transplant, followed by post-transplant cyclophosphamide (PTCy). The number of HLA-mismatched antigens was tested for its impact on overall survival (OS) and nonrelapse mortality (NRM), whereas HLA mismatches in the graft-versus-host (GVH) direction were tested for prediction of graft-versus-host disease (GVHD and relapse. Finally, we studied whether graft rejection correlated with the number of HLA mismatched antigens in host-versus-graft (HVG) direction. Two hundred thirty-one donor-recipient pairs (72%) had 4/8 mismatches at the -A, -B, -C, -DRB1 HLA loci. HLA mismatches did not predict the 2-year OS (hazard ratio, .83; P = .58) and NRM (subhazard ratio, 1.08; P = .93). The cumulative incidence of acute GVHD (P = .13), 1-year chronic GVHD (P = .84), and relapse rate (P = .26) did not correlate with univectorial GVH mismatches. Similarly, no correlation was observed between the amount of HLA mismatch in the HVG direction and graft rejection. In multivariate analysis advanced disease at transplant was the strongest predictor of survival, NRM, relapse, and graft rejection. In conclusion, the degree of HLA mismatching should not be used as a criterion to select family haploidentical donors when using bone marrow as stem cell source and PTCy for GVHD prophylaxis.

Disease relapse remains an unmet medical need for patients with Hodgkin lymphoma (HL) receiving an allogeneic hematopoietic cell transplantation (HCT). With the aim of identifying patients at high risk for post-transplant relapse, we retrospectively reviewed 41 HL patients who had received haploidentical (haplo) nonmyeloablative (NMA) HCT with high dose post-transplant cyclophosphamide (PT-Cy) for graft-versus-host (GVHD) prophylaxis. Primary refractory disease, relapse within 6 months from autologous stem cell transplantation, age, pretransplant chemotherapy, HCT comorbidity index (HCT-CI), sex mismatch, tumor burden and pretransplant fluorodeoxyglucose positron emission tomography (FDG-PET) status, assessed by Deauville score, were analyzed as variables influencing outcomes. All but 1 patient engrafted: median time to neutrophil and platelet recovery was 15 (interquartile range, 13 to 23) days and 19 (interquartile range, 12 to 28) days, respectively. Cumulative incidence of severe (grade III to IV) acute graft-versus-host disease (GVHD) and 3-year moderate-severe chronic GVHD was 2.4% and 11.8%, respectively. The 3-year overall (OS), progression free (PFS), and graft relapse-free survival (GRFS) were 75.6%, 43.9%, and 39%, respectively. On multivariate analysis, 3-year OS was significantly worse in patients with HCT-CI ≥3 (hazard ratio [HR], 5.0; 95% confidence interval [CI], 1.1 to 21.8; P = .03). Three-year relapse rate, 3-year PFS, and 3-year GRFS were significantly worse in patients with HCT-CI ≥3 (HR, 3.5; 95% CI, 1.3 to 9.3; P = .01; HR, 3.3; 95% CI, 1.2 to 9.0; P = .02; and HR, 4.2; 95% CI, 1.7 to 9.9; P = .001, respectively) and in patients with a Deauville score ≥4 on pretransplant FDG-PET (HR, 4.4; 95% CI, 1.6-12.4; P = .005, HR, 3.8; 95% CI, 1.5 to 9.7; P = .005; and 3.2; 95% CI, 1.3 to 7.9; P = .01, respectively). On univariate analysis, 3-year NRM was significantly worse only in patients with a HCT-CI ≥3 (HR, 17.6; 95% CI, 1.4 to 221.0). Among relapsed or refractory HL patients undergoing haplo NMA HCT with PT-Cy, pretransplant FDG-PET with a Deauville score ≥4 and HCT-CI ≥3 identified patients at high risk of relapse. Moreover, an HCT-CI ≥3 was associated with higher NRM and lower OS.

Asciminib is a potent and selective inhibitor of BCR::ABL1, with potential to avoid toxicity resulting from off-target kinase inhibition. Forty-nine patients treated with asciminib under a managed access program in the UK were evaluated for toxicity and response. Intolerance, rather than resistance (65% vs. 35%), was the most common reason for cessation of the last-line of treatment but asciminib was well tolerated, with most patients (29, 59%) remaining on treatment at a median of 14 months follow-up, and only 6 (12%) stopping for intolerance. Of 44 patients assessable for response, 29 (66%) achieved a complete cytogenetic response (CCyR) or better, with poorer responses seen in those stopping their last-line of therapy for resistance. Fewer patients with a prior history of a non-T315I-BCR::ABL1 single nucleotide variant (BSNV), or a non-T315I-BSNV detectable at baseline achieved CCyR. Serial tracking of BSNV by next generation sequencing demonstrated clonal expansion of BSNV-harbouring populations, which in some settings was associated with resistance (E459K, F317L, F359I), while in others was seen in the context of ongoing response, often with intensified dosing (T315I, I502F). These data suggest that asciminib exerts selective pressure on some BSNV-harbouring populations in vivo, some of which may respond to intensified dosing.

Ruxolitinib has become the new standard of care for steroid-refractory and steroid-dependent chronic GVHD (SR-cGVHD). Our aim was to collect comparative data between ruxolitinib and extracorporeal photophoresis (ECP). We asked EBMT centers if they were willing to provide detailed information on GVHD grading, -therapy, -dosing, -response and complications for each included patient. 31 centers responded positively and we included all patients between 1/2017-7/2019 treated with ECP or ruxolitinib for moderate or severe SR-cGVHD. We identified 84 and 57 patients with ECP and ruxolitinib, respectively. We performed multivariate analyses adjusted on grading and type of SR-cGVHD (steroid dependent vs. refractory vs. intolerant to steroids). At day+180 after initiation of treatment for SR-cGVHD the odds ratio in the ruxolitinib group to achieve overall response vs. the ECP group was 1.35 (95% CI = [0.64; 2.91], p = 0.43). In line, we detected no statistically significant differences in overall survival, progression-free survival, non-relapse mortality and relapse incidence. The clinical significance is limited by the retrospective study design and the current data can’t replace prospective studies on ECP in SR-cGVHD. However, the present results contribute to the accumulating evidence on ECP as an effective treatment option in SR-cGVHD.