Hypomethylating Agents and Venetoclax for Acute Myeloid Leukemia Relapsed After Hematopoietic Stem Cell Transplant.

BACKGROUND: Hypomethylating agent + venetoclax is an effective frontline combination for acute myeloid leukemia, but its efficacy and safety in post-allogeneic hematopoietic cell transplant (alloHCT) relapse remain underexplored. Outcomes have been poor for this population, with no standard treatment. PATIENTS AND METHODS: We retrospectively analyzed 72 Ven-naïve patients who received hypomethylating agents + venetoclax at relapse following alloHCT and aimed to evaluate the rates of complete remission with or without hematologic recovery (CR/CRi) and minimal residual disease (MRD) negativity, CR/CRi duration, and overall survival. We leveraged our larger sample to analyze the impact of cytogenetic/molecular features on the odds of CR/CRi. RESULTS: CR/CRi was achieved among 32 of 67 (48%) patients, and MRD negativity was recorded among 10 of 12. NPM1 and IDH 1 or 2 mutations increased the odds of CR/CRi, as did increasing time from alloHCT to relapse. Fourteen patients subsequently received donor lymphocyte infusions or a second alloHCT. Responses lasted a median of 17.8 months (95% CI, 7.2 months to not reached), and responders had a greater median overall survival of 19.7 months (95% CI, 7.6-51.5 months) compared to 2.9 months among nonresponders (95% CI, 1.8-4.4 months; log-rank P < .01). Treatment was well tolerated, but prolonged cytopenias were common and most patients required reduction in the number of venetoclax days per cycle. CONCLUSION: These data support the efficacy of this combination in the alloHCT relapse setting where we report responses among nearly half of patients, with possibly greater benefit for NPM1 and IDH 1/2-mutated cases. These responses can be durable and profound as evidenced by conversion to MRD negativity.

Association between CYP3A4, CYP3A5 and ABCB1 genotype and tacrolimus treatment outcomes among allogeneic HSCT patients.

Aim: Successful treatment with tacrolimus to prevent graft versus host disease (GVHD) and minimize tacrolimus-related toxicities among allogeneic hematopoietic cell transplantation (alloHCT) recipients is contingent upon quickly achieving and maintaining concentrations within a narrow therapeutic range. The primary objective was to investigate associations between CYP3A4, CYP3A5 or ABCB1 genotype and the proportion of patients that attained an initial tacrolimus goal concentration following initiation of intravenous (iv.) and conversion to oral administration. Materials & methods: We retrospectively evaluated 86 patients who underwent HLA-matched (8/8) related donor alloHCT and were prescribed a tacrolimus-based regimen for GVHD prophylaxis. Results & conclusion: The findings of the present study suggests that CYP3A5 genotype may impact attainment of initial therapeutic tacrolimus concentrations with oral administration in alloHCT recipients.

Sirolimus Is an Acceptable Alternative to Tacrolimus for Graft-versus-Host Disease Prophylaxis after Haploidentical Peripheral Blood Stem Cell Transplantation with Post-Transplantation Cyclophosphamide.

Graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (PTCy), tacrolimus (Tac), and mycophenolate mofetil (MMF) for allogeneic haploidentical donor (haplo) hematopoietic cell transplantation (HCT) results in comparable outcomes to matched unrelated donor HCT. A phase II study from the Moffitt Cancer Center substituting sirolimus (Siro) for Tac in this prophylactic regimen reported comparable rates of grade II-IV acute GVHD (aGVHD). Many centers have substituted Siro for Tac in this setting based on a preferable side effect profile, although comparative data are limited. In this study, we retrospectively compared outcomes in haplo-HCT with PTCy/Siro/MMF versus haplo-HCT with PTCy/Tac/MMF. The study cohort included all consecutive patients receiving haploidentical donor T cell-replete peripheral blood stem cell (PBSC) HCT for hematologic malignancies at Moffitt Cancer Center or the City of Hope National Medical Center between 2014 and 2019. A total of 423 patients were included, of whom 84 (20%) received PTCy/Siro/MMF and 339 (80%) received PTCy/Tac/MMF. The median age for the entire cohort was 54 years (range, 18 to 78 years), and the median follow-up was 30 months. The Siro group had a higher proportion of patients age ≥60 years (58% versus 34%; P < .01), and the groups also differed in diagnosis type, conditioning regimen, and cytomegalovirus serostatus. There were no significant differences in the rates of grade II-IV aGVHD (45% versus 47%; P = .6) at day +100 or chronic GVHD (cGVHD) (47% versus 54%; P = .79) at 2 years post-HCT. In multivariate analysis, neutrophil engraftment at day +30 was significantly better in the Tac group (odds ratio, .30; 95% confidence interval, .1 to .83; P = .02), with a median time to engraftment of 17 days versus 18 days in the Siro group, but platelet engraftment was similar in the 2 groups. Otherwise, in multivariate analysis, GVHD prophylaxis type had no significant influence on aGVHD or cGVHD, nonrelapse mortality, relapse, GVHD-free relapse-free survival, disease-free survival, or overall survival after PBSC haplo-HCT. These findings suggest that Siro is a comparable alternative to Tac in combination with PTCy/MMF for GVHD prophylaxis, with overall similar clinical outcomes despite delayed engraftment after peripheral blood stem cell haplo-HCT. Although Tac remains the standard of care, Siro may be substituted based on the side effect profile of these medications, with consideration of patient medical comorbidities at HCT.

Haploidentical donor hematopoietic cell transplantation for myelodysplastic/myeloproliferative overlap neoplasms: results from a North American collaboration.

Haploidentical donors offer a potentially readily available donor, especially for non-White patients, for hematopoietic cell transplantation (HCT). In this North American collaboration, we retrospectively analyzed outcomes of first HCT using haploidentical donor and post-transplantation cyclophosphamide (PTCy) in myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) overlap neoplasms (MDS/MPN). We included 120 consecutive patients who underwent HCT using a haploidentical donor for MDS/MPN across 15 centers. Median age was 62.5 years and 38% were of non-White/Caucasian ethnicity. The median follow-up was 2.4 years. Graft failure was reported in seven of 120 (6%) patients. At 3 years, nonrelapse mortality (NRM) was 25% (95% confidence interval [CI]: 17-34), relapse 27% (95% CI: 18-36), grade 3-4 acute graftversus- host disease 12% (95% CI: 6-18), chronic graft-versus-host disease requiring systemic immunosuppression 14% (95% CI: 7-20), progression-free survival (PFS) 48% (95% CI: 39-59), and overall survival (OS) 56% (95% CI: 47-67). On multivariable analysis, NRM was statistically significantly associated with advancing age at HCT (per decade increment, subdistribution hazard ratio [sdHR] =3.28; 95% CI: 1.30-8.25); relapse with the presence of mutation in EZH2/RUNX1/SETBP1 (sdHR=2.61; 95% CI: 1.06-6.44); PFS with advancing age at HCT (per decade increment, HR=1.98, 95% CI: 1.13-3.45); and OS with advancing age at HCT (per decade increment, HR=2.01; 95% CI: 1.11-3.63) and splenomegaly at HCT/prior splenectomy (HR=2.20; 95% CI: 1.04-4.65). Haploidentical donors are a viable option for HCT in MDS/MPN, especially for those disproportionately represented in the unrelated donor registry. Hence, donor mismatch should not preclude HCT for patients with MDS/MPN, an otherwise incurable malignancy. In addition to patient age, disease-related factors including splenomegaly and high-risk mutations dominate outcomes following HCT.

Cardiac events after standard of care idecabtagene vicleucel for relapsed and refractory multiple myeloma.

Idecabtagene vicleucel (ide-cel) is a type of B-cell maturation antigen (BCMA)-targeting chimeric antigen receptor T-cell (CAR-T) approved for the treatment of relapsed and refractory multiple myeloma (RRMM). Currently, the incidence of cardiac events associated with ide-cel remains unclear. This was a retrospective single-center observational study of patients treated with ide-cel for RRMM. We included all consecutive patients who received standard-of-care ide-cel treatment at least 1-month follow-up. Baseline clinical risk factors, safety profile, and responses were examined based on the development of a cardiac event. A total of 78 patients were treated with ide-cel, and 11 patients (14.1%) developed cardiac events: heart failure (5.1%), atrial fibrillation (10.3%), nonsustained ventricular tachycardia (3.8%), and cardiovascular death (1.3%). Only 11 of the 78 patients had repeat echocardiogram. Baseline risk factors associated with the development of cardiac events included being female sex and having poor performance status, λ light-chain disease, and advanced Revised International Staging System stage. Baseline cardiac characteristics were not associated with cardiac events. During index hospitalization after CAR-T, higher-grade (≥grade 2) cytokine release syndrome (CRS) and immune cell-associated neurologic syndrome were associated with cardiac events. In multivariable analyses, the hazard ratio for the association of the presence of cardiac events with overall survival (OS) was 2.66 and progression-free survival (PFS) was 1.98. Ide-cel CAR-T for RRMM was associated with similar cardiac events as other types of CAR-T. Worse baseline performance status and higher-grade CRS and neurotoxicity were associated with cardiac events after BCMA-directed CAR-T-cell therapy. Our results suggest that the presence of cardiac events may confer worse PFS or OS; although because of the small sample size, the power to detect an association was limited.

Post-Transplantation Cyclophosphamide-Based Graft-versus-Host Disease Prophylaxis.

BACKGROUND: In patients undergoing allogeneic hematopoietic stem-cell transplantation (HSCT), a calcineurin inhibitor plus methotrexate has been a standard prophylaxis against graft-versus-host disease (GVHD). A phase 2 study indicated the potential superiority of a post-transplantation regimen of cyclophosphamide, tacrolimus, and mycophenolate mofetil. METHODS: In a phase 3 trial, we randomly assigned adults with hematologic cancers in a 1:1 ratio to receive cyclophosphamide-tacrolimus-mycophenolate mofetil (experimental prophylaxis) or tacrolimus-methotrexate (standard prophylaxis). The patients underwent HSCT from an HLA-matched related donor or a matched or 7/8 mismatched (i.e., mismatched at only one of the HLA-A, HLA-B, HLA-C, and HLA-DRB1 loci) unrelated donor, after reduced-intensity conditioning. The primary end point was GVHD-free, relapse-free survival at 1 year, assessed in a time-to-event analysis, with events defined as grade III or IV acute GVHD, chronic GVHD warranting systemic immunosuppression, disease relapse or progression, and death from any cause. RESULTS: In a multivariate Cox regression analysis, GVHD-free, relapse-free survival was significantly more common among the 214 patients in the experimental-prophylaxis group than among the 217 patients in the standard-prophylaxis group (hazard ratio for grade III or IV acute GVHD, chronic GVHD, disease relapse or progression, or death, 0.64; 95% confidence interval [CI], 0.49 to 0.83; P = 0.001). At 1 year, the adjusted GVHD-free, relapse-free survival was 52.7% (95% CI, 45.8 to 59.2) with experimental prophylaxis and 34.9% (95% CI, 28.6 to 41.3) with standard prophylaxis. Patients in the experimental-prophylaxis group appeared to have less severe acute or chronic GVHD and a higher incidence of immunosuppression-free survival at 1 year. Overall and disease-free survival, relapse, transplantation-related death, and engraftment did not differ substantially between the groups. CONCLUSIONS: Among patients undergoing allogeneic HLA-matched HSCT with reduced-intensity conditioning, GVHD-free, relapse-free survival at 1 year was significantly more common among those who received cyclophosphamide-tacrolimus-mycophenolate mofetil than among those who received tacrolimus-methotrexate. (Funded by the National Heart, Lung, and Blood Institute and others; BMT CTN 1703 ClinicalTrials.gov number, NCT03959241.).

Haploidentical Donor Blood or Marrow Transplantation for Myelodysplastic/Myeloproliferative Overlap Neoplasms: Results from a North American Collaboration.

Haploidentical donors offer a potentially readily available donor, especially for non-White patients, for blood or marrow transplantation (BMT). In this collaboration across North America, we retrospectively analyzed outcomes of first BMT using haploidentical donor and posttransplantation cyclophosphamide (PTCy) in MDS/MPN-overlap neoplasms (MDS/MPN), an otherwise incurable hematological neoplasm. We included 120 patients, 38% of non-White/Caucasian ethnicity, across 15 centers with median age at BMT 62.5 years. The median follow-up is 2.4 years. Graft failure was reported in 6% patients. At 3-years, nonrelapse mortality (NRM) was 25%, relapse 27%, grade 3-4 acute graft versus host disease (GVHD) 12%, chronic GVHD requiring systemic immunosuppression 14%, progression-free survival (PFS) 48% and overall survival (OS) 56%. On multivariable analysis, statistically significant associations included older age at BMT (per decade increment) with NRM (sdHR 3.28, 95%CI 1.30-8.25), PFS (HR 1.98, 95% 1.13-3.45) and OS (HR 2.01, 95% CI 1.11-3.63), presence of mutation in EZH2/RUNX1/SETBP1 with relapse (sdHR 2.61, 95%CI 1.06-6.44), and splenomegaly at BMT/prior splenectomy with OS (HR 2.20, 95%CI 1.04-4.65). Haploidentical donors are a viable option for BMT in MDS/MPN, especially for those disproportionately represented in the unrelated donor registry. Disease-related factors including splenomegaly and high-risk mutations dominate outcomes following BMT.

Trends and in-hospital cardiac complications in patients with atrial fibrillation undergoing allogeneic stem cell transplant: A National Inpatient Sample analysis (2002-2019).

BACKGROUND: Cardiovascular comorbidities increase the risk of transplant-associated complications. However, the impact of atrial fibrillation (AF) as an independent risk factor remains limited. METHODS: The National Inpatient Sample (NIS) database was queried using the International Classification of Diseases codes to identify patients admitted for allogeneic stem cell transplant (ASCT). The patients were then subclassified into with and without AF. Subsequently, a multivariate logistic regression model was constructed to account for patient demographics, comorbidities, and hospital characteristics to evaluate the impact of AF on the primary outcome of interest: all-cause mortality, and secondary outcomes of interest that included common hospitalization complications. RESULTS: The data for 77 157 cases of ASCT were collected between 2002 and 2019. Among these 5086 (6.6%) cases had concurrent AF. Multivariate logistic regression revealed patients undergoing ASCT with AF had almost a three times higher risk of all-cause mortality (odds ratio = 2.99 [95% confidence interval: 2.73-3.28]; p < .01). AF patients also had a higher risk for cardiac arrest, cardiogenic shock, acute kidney injury, and need for hemodialysis (all p < .01). CONCLUSION: AF causes a higher risk of death and cardiovascular complications among patients undergoing ASCT. This signifies the importance of pretransplant consultation and optimization for cardiovascular comorbidities to improve hospitalization outcomes.

NCCN Guidelines® Insights: Hematopoietic Cell Transplantation, Version 3.2022.

The NCCN Guidelines for Hematopoietic Cell Transplantation (HCT) provide an evidence- and consensus-based approach for the use of autologous and allogeneic HCT in the management of malignant diseases in adult patients. HCT is a potentially curative treatment option for patients with certain types of malignancies; however, recurrent malignancy and transplant-related complications often limit the long-term survival of HCT recipients. The purpose of these guidelines is to provide guidance regarding aspects of HCT, including pretransplant recipient evaluation, hematopoietic cell mobilization, and treatment of graft-versus-host disease-a major complication of allogeneic HCT-to enable the patient and clinician to assess management options in the context of an individual patient's condition. These NCCN Guidelines Insights provide a summary of the important recent updates to the NCCN Guidelines for HCT, including the incorporation of a newly developed section on the Principles of Conditioning for HCT.

Allogeneic hematopoietic stem cell transplant outcomes in adults with inherited myeloid malignancies.

There is increasing recognition that pathogenic germ line variants drive the development of hematopoietic cancers in many individuals. Currently, patients with hereditary hematologic malignancies (HHMs) receive similar standard therapies and hematopoietic stem cell transplant (HSCT) approaches as those with sporadic disease. We hypothesize that patients with myeloid malignancies and deleterious germ line predisposition variants have different posttransplant outcomes than those without such alleles. We studied 472 patients with myeloid neoplasms, of whom 26% had deleterious germ line variants and 34% underwent HSCT. Deleterious germ line variants in CHEK2 and DDX41 were most commonly seen in American and Australian cohorts, respectively. Patients with deleterious germ line DDX41 variants had a higher incidence of severe (stage 3-4) acute graft-versus-host disease (GVHD) (38%) than recipients with deleterious CHEK2 variants (0%), other HHM variants (12%), or patients without such germ line variants (9%) (P = .002). Importantly, the use of posttransplant cyclophosphamide reduced the risk of severe acute GVHD in patients receiving HSCT for deleterious germ line DDX41-associated myeloid neoplasms (0% vs 53%, P = .03). Based on these results, we advocate the use of posttransplant cyclophosphamide when individuals with deleterious germ line DDX41 variants undergo allogeneic HSCT for myeloid malignancies, even when transplantation has been performed using wild-type donors.

Outcomes of CD19-Targeted Chimeric Antigen Receptor T Cell Therapy for Patients with Reduced Renal Function Including Dialysis.

Patients with renal impairment (RI) are typically excluded from trials evaluating chimeric antigen receptor (CAR) T cell therapies. We evaluated the outcomes of patients with RI receiving standard of care (SOC) CAR T cell therapy for relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). In this retrospective, single-center cohort study of patients with R/R DLBCL treated with SOC axicabtagene ciloleucel (axi-cel) or tisagenlecleucel (tisa-cel) after 2 or more prior lines of therapy, renal and survival outcomes were compared based on RI and fludarabine dose reduction (DR) status. RI was defined by an estimated glomerular filtration rate <60 mL/min/1.73 m2 as determined by the Modification of Diet in Renal Disease equation using day -5 creatinine (Cr) values. Acute kidney injury (AKI) was identified and graded using standard Kidney Disease: Improving Global Outcomes criteria. Renal recovery was considered to occur if Cr was within .2 mg/mL of baseline by day +30. Fludarabine was considered DR if given at <90% of the recommended Food and Drug Administration label dose. Among 166 patients treated with CAR T cell therapy were 17 patients (10.2%) with baseline RI and 149 (89.8%) without RI. After CAR T cell infusion, the incidence of any grade AKI was not significantly different between patients with baseline RI and those without RI (42% versus 21%; P = .08). Similarly, severe grade 2/3 AKI was seen in 1 of 17 patients (5.8%) with baseline RI and in 11 of 149 patients (7.3%) without RI (P = 1). Decreased renal perfusion (28 of 39; 72%) was the most common cause of AKI, with cytokine release syndrome (CRS) contributing to 17 of 39 AKIs (44%). Progression-free survival (PFS) and overall survival (OS) did not differ between patients with RI and those without RI or between those who received standard-dose fludarabine and those who received reduced-dose fludarabine. In contrast, patients with AKI had worse clinical outcomes than those without AKI (multivariable PFS: hazard ratio [HR], 2.1; 95% confidence interval [CI], 1.2 to 3.7; OS: HR, 3.9; 95% CI, 2.1 to 7.4). Notably, peak inflammatory cytokine levels were higher in patients who experienced AKI. Finally, we describe 2 patients with end-stage renal disease (ESRD) on dialysis who received lymphodepletion and CAR T cell therapy. Baseline renal function did not affect renal or efficacy outcomes after CAR T cell therapy in DLBCL. On the other hand, patients with AKI went on to experience worse clinical outcomes. AKI was commonly related to CRS and high peak inflammatory cytokine levels. CAR T cell therapy is feasible in patients with ESRD and requires careful planning of lymphodepletion.

Early cytopenias and infections after standard of care idecabtagene vicleucel in relapsed or refractory multiple myeloma.

Idecabtagene vicleucel (ide-cel) was FDA-approved in March 2021 for the treatment of relapsed/refractory multiple myeloma after 4 lines of therapy. On the KarMMa trial, grade ≥ 3 cytopenias and infections were common. We sought to characterize cytopenias and infections within 100 days after ide-cel in the standard-of-care (SOC) setting. This multi-center retrospective study included 52 patients who received SOC ide-cel; 47 reached day-90 follow-up. Data were censored at day 100. Grade ≥ 3 cytopenia was present among 65% of patients at day 30 and 40% of patients at day 90. Granulocyte colony stimulating factor (G-CSF) was administered to 88%, packed red blood cell transfusions to 63%, platelet transfusions to 42%, thrombopoietin (TPO) agonists to 21%, intravenous immunoglobulin to 13%, and CD34+ stem cell boosts to 8%. At day 100, 19% and 13% of patients had ongoing use of TPO agonists and G-CSF, respectively. Infections occurred in 54% of patients and were grade ≥ 3 in 23%. Earlier infections in the first 30 days were typically bacterial (68%) and severe (50%). Later infections between days 31 and 100 were 50% bacterial and 42% viral; only 13% were grade ≥ 3. On univariate analysis, high pre-CAR-T marrow myeloma burden (≥ 50%), circulating plasma cells at pre-lymphodepletion (LD), and grade ≥ 3 anemia at pre-LD were associated with grade ≥ 3 cytopenia at both days 30 and 90. Longer time from last bridging treatment to LD was the only significant risk factor for infection.

Post-Transplantation Cyclophosphamide-Based Graft- versus-Host Disease Prophylaxis with Nonmyeloablative Conditioning for Blood or Marrow Transplantation for Myelofibrosis.

We describe outcomes after post-transplantation cyclophosphamide and nonmyeloablative conditioning-based allogeneic blood or marrow transplantation for myelofibrosis using matched or mismatched related or unrelated donors. The conditioning regimen consisted of fludarabine, cyclophosphamide, and total body irradiation. Forty-two patients were included, with a median age of 63 years, of whom 19% had Dynamic International Prognostic Scoring System (DIPSS)-plus intermediate-1 risk, 60% had intermediate-2 risk, and 21% had high-risk disease, and 60% had at least 1 high-risk somatic mutation. More than 90% of patients engrafted neutrophils, at a median of 19.5 days, and 7% experienced graft failure. At 1 year and 3 years, respectively, overall survival was 65% and 60%, relapse-free survival was 65% and 31%, relapse was 5% and 40%, and nonrelapse mortality was 30% and 30%. Acute graft-versus-host disease grade 3-4 was seen in 17% of patients at 1 year, and chronic graft-versus-host disease requiring systemic therapy in occurred in 12% patients. Spleen size ≥17 cm or prior splenectomy was associated with inferior relapse-free survival (hazard ratio [HR], 3.50; 95% confidence interval [CI], 1.18 to 10.37; P = .02) and higher relapse rate (subdistribution HR [SDHR] not calculable; P = .01). Age >60 years (SDHR, 0.26; 95% CI, 0.08 to 0.80, P = .02) and receipt of peripheral blood grafts (SDHR, 0.34; 95% CI, 0.11 to 0.99; P = .05) were associated with a lower risk of relapse. In our limited sample, the presence of a high-risk mutation was not statistically significantly associated with an inferior outcome, although ASXL1 was suggestive of inferior survival (SDHR, 2.36; 95% CI, 0.85 to 6.6; P = .09). Overall, this approach shows outcomes comparable those of to previously reported approaches and underscores the importance of spleen size in the evaluation of transplantation candidates.

Outcomes Following Intolerance to Tacrolimus/Sirolimus Graft-versus-Host Disease Prophylaxis for Allogeneic Hematopoietic Cell Transplantation.

Although tacrolimus and sirolimus (TAC/SIR) is an accepted graft-versus-host disease (GVHD) prophylaxis regimen following allogeneic hematopoietic cell transplantation (HCT), toxicity from this regimen can lead to premature discontinuation of immunosuppression. There are limited studies reporting outcomes and subsequent treatment of patients with TAC/SIR intolerance. This study was conducted to assess the outcomes of patients with TAC/SIR intolerance and guide their subsequent management. We retrospectively analyzed transplantation outcomes of consecutive adult patients at Moffitt Cancer Center who underwent allogeneic HCT with TAC/SIR as GVHD prophylaxis between 2009 and 2018. TAC/SIR intolerance was defined as discontinuation of either TAC or SIR due to toxicity before post-transplantation day +100. A total of 777 patients met the inclusion criteria. The median duration of follow-up was 22 months (range, 0.2 to 125 months). Intolerance occurred in 13% (n = 104) of the patients at a median of 30 days (range, 5 to 90 days). The most common causes of intolerance were acute kidney injury (n = 53; 51%), thrombotic microangiopathy (n = 31; 28%), and veno-occlusive disease (n = 23; 22%). The cumulative incidence of grade II-IV acute GVHD at 100 days was 50% (95% CI, 39% to 64%) in the TAC/SIR-intolerant patients and 25% (95% CI, 22% to 29%) in patients tolerant to this regimen (P < .0001). In multivariate analyses, the incidence of grade II-IV 4 acute GVHD was significantly higher in the TAC/SIR-intolerant patients (hazard ratio [HR], 2.40; 95% CI, 1.59 to 3.61; P < .0001). Similarly, in multivariate analyses, the TAC/SIR-intolerant patients had a higher incidence of chronic GVHD (HR, 1.48; 95% CI, 1.03 to 2.12; P = .03). The nonrelapse mortality (NRM) at 1 year was 47% (95% CI, 38% to 59%) in the TAC/SIR-intolerant patients and 12% (95% CI, 10% to 15%) in those tolerant to the regimen (P < .0001). The 2-year relapse-free survival was 35% (95% CI, 25% to 44%) in the TAC/SIR-intolerant patients and 60% (95% CI, 57% to 65%) in the TAC/SIR-tolerant patients (HR, 2.30; 95% CI, 1.61 to 3.28; P < .0001). Intolerance stratified by early (≤30 days) versus late (31 to 100 days) significantly affected the cumulative incidence of acute GVHD at 75% (early; 95% CI, 59% to 94%) versus 33% (late; 95% CI, 21% to 50%) (P = .001), as well as the cumulative incidence of NRM at 61% (early; 95% CI, 48% to 77%) versus 35% (late; 95% CI, 24% to 51%) (P = .006). Most patients who developed TAC/SIR intolerance were switched to an alternative 2-drug regimen (71 of 104; 68%), most commonly mycophenolate mofetil in addition to continuing TAC or SIR (68 of 71; 96%). Overall, TAC/SIR intolerance was associated with poorer outcomes. Early intolerance contributed to a higher risk of acute GVHD, increased NRM, and inferior survival. Patients with early intolerance were often switched to an alternative agent, and patients with late intolerance tended to be continued on single-drug therapy without substitution. The use of single-drug versus 2-drug regimens after intolerance did not appear to affect outcomes. Management strategies to mitigate the risks of intolerance are warranted.

Umbilical Cord Blood or HLA-Haploidentical Transplantation: Real-World Outcomes versus Randomized Trial Outcomes.

Randomized clinical trials offer the highest-quality data for modifying clinical practice. Results of a phase III randomized trial of nonmyeloablative transplantation for adults with high-risk hematologic malignancies with 2 umbilical cord blood (UCB) units (n = 183) or HLA-haploidentical relative bone marrow (Haplo-BM; n = 154) revealed a 2-year progression-free survival (PFS) of 41% after Haplo-BM transplantation and 35% after 2-unit UCB transplantation (P = .41), with overall survival (OS) of 57% and 46%, respectively (P = .04). We sought to examine the generalizability of BMT CTN 1101 to a contemporaneous cohort beyond the trial's prespecified 2-year outcomes. All transplantations were performed between June 2012 and June 2018 in the United States. We hypothesized that the results of a rigorous phase III randomized trial would be generalizable. Changes in graft selection for HLA-haploidentical relative transplantation during the trial period allowed comparison of outcomes after transplantation with Haplo-BM with those after haploidentical peripheral blood (Haplo-PB). The trial's broad eligibility criteria were applied to the data source of the Center for International Blood and Marrow Transplant Research to select nontrial subjects. Extended follow-up of trial subjects was obtained from this data source. Three separate analyses were performed: (1) trial subjects beyond the trial's 2-year endpoint; (2) comparison of trial subjects with a contemporaneous cohort of nontrial subjects (195 2-unit UCB, 358 Haplo-BM, and 403 Haplo-PB); and (3) comparison of nontrial subjects by donor and graft type. Multivariate analyses were performed using Cox proportional hazards models for comparison of outcomes by treatment groups. With longer follow-up of the trial cohorts, 5-year PFS (37% versus 29%; P = .08) and OS (42% versus 36%; P = .06) were not significantly different between the treatment groups. We then compared the trial results with outcomes of comparable real-world transplantations. Five-year OS did not differ between trial and nontrial 2-unit UCB transplantations (36% versus 41%; P = .48) or between trial and nontrial Haplo-BM transplantations (42% versus 47%; P = .80), confirming generalizability. The randomized trial did not accrue as planned and therefore lacked the statistical power to detect a 15% difference in PFS. With substantially larger numbers of nontrial Haplo-BM transplantations, 5-year survival was higher after nontrial Haplo-BM compared with trial 2-unit UCB (47% versus 36%; P = .012). Nontrial patients who underwent Haplo-PB transplantation had higher 5-year survival (54%) compared with trial Haplo-BM (hazard ratio [HR], 0.76; P = .044) and nontrial Haplo-BM (HR, 0.78; P = .026). Similarly, survival was better after Haplo-PB compared with trial UCB (HR, 0.57; P < .0001) and nontrial UCB (HR, 0.63; P = .0002). When considering alternative donor low-intensity conditioning regimen transplantation, a haploidentical relative is preferred, and PB is the preferred graft source.

Cytokine Release Syndrome Following Peripheral Blood Stem Cell Haploidentical Hematopoietic Cell Transplantation with Post-Transplantation Cyclophosphamide.

Post-transplantation cyclophosphamide (PTCy) is a safe and efficacious graft-versus-host-disease (GVHD) prophylaxis following hematopoietic cell transplantation (HCT) from a haploidentical (haplo) donor. Cytokine release syndrome (CRS) is a common complication of this platform. Early fever post-haplo-HCT using bone marrow grafts is associated with higher CD3+ cell dose and CRS. However, the impact of CD3+ and CD34+ cell dose on CRS post-haplo-HCT using peripheral blood stem cell (PBSC) grafts is unknown. Our goals were to evaluate the incidence of CRS following PBSC transplantation (PBSCT) and to identify factors that can be modified to prevent the development of severe CRS in this setting. In 271 patients, we investigated factors associated with the development of CRS following haplo-PBSCT and examined the impact of CRS on clinical outcomes. Ninety-three percent of the patients developed CRS of any grade post-haplo-PBSCT. In multivariate analysis, severe CRS (grade 3-4 versus grade 0-1) was associated with higher nonrelapse mortality (hazard ratio [HR], 6.42; 95% confidence interval [CI], 2.68 to 15.39; P < .001), worse 1-year overall survival (HR, 3.40; 95% CI, 1.63 to 7.08; P = .005), and worse disease-free survival (HR, 4.02; 95% CI, 1.99 to 8.08; P < .001). Moderate to severe CRS (grade 2-4) did not impact 1-year relapse or acute GVHD (grade II-IV and III-IV) at 100 days (P = .71 and .19, respectively). Importantly, higher CD3+ cell dose, but not CD34+ cell dose, predicted a higher incidence of grade 2-4 CRS (HR, 1.20; 95% CI,1.07 to 1.36; P = .003) and grade 3-4 CRS (HR, 1.40; 95% CI, 1.05 to 1.86; P = .022). Both older age (HR, 8.57; 95% CI, 1.73 to 42.36; P < .001) and non-total body irradiation-based reduced-intensity conditioning with fludarabine/melphalan (HR, 15.38; 955 CI, 2.06 to 114.67; P < .001) were predictive of grade 3-4 CRS. Overall, we observed that severe CRS (grade 3-4) negatively affected transplantation outcome, and that higher CD3 cell dose was associated with the development of any grade CRS and severe CRS.

Allogeneic blood or marrow transplantation with haploidentical donor and post-transplantation cyclophosphamide in patients with myelofibrosis: a multicenter study.

We report the results from a multicenter retrospective study of 69 adult patients who underwent haploidentical blood or marrow transplantation (haplo-BMT) with post-transplantation cyclophosphamide (PTCy) for chronic phase myelofibrosis. The median age at BMT was 63 years (range, 41-74). Conditioning regimens were reduced intensity in 54% and nonmyeloablative in 39%. Peripheral blood grafts were used in 86%. The median follow-up was 23.1 months (range, 1.6-75.7). At 3 years, the overall survival, relapse-free survival (RFS), and graft-versus-host-disease (GVHD)-free-RFS were 72% (95% CI 59-81), 44% (95% CI 29-59), and 30% (95% CI 17-43). Cumulative incidences of non-relapse mortality and relapse were 23% (95% CI 14-34) and 31% (95% CI 17-47) at 3 years. Spleen size ≥22 cm or prior splenectomy (HR 6.37, 95% CI 2.02-20.1, P = 0.002), and bone marrow grafts (HR 4.92, 95% CI 1.68-14.4, P = 0.004) were associated with increased incidence of relapse. Cumulative incidence of acute GVHD grade 3-4 was 10% at 3 months and extensive chronic GVHD was 8%. Neutrophil engraftment was reported in 94% patients, at a median of 20 days (range, 14-70). In conclusion, haplo-BMT with PTCy is feasible in patients with myelofibrosis. Splenomegaly ≥22 cm and bone marrow grafts were associated with a higher incidence of relapse in this study.

Increased Infections and Delayed CD4+ T Cell but Faster B Cell Immune Reconstitution after Post-Transplantation Cyclophosphamide Compared to Conventional GVHD Prophylaxis in Allogeneic Transplantation.

Post-transplantation cyclophosphamide (PTCy) is being increasingly used for graft-versus-host disease (GVHD) prophylaxis after allogeneic hematopoietic cell transplantation (allo-HCT) across various donor types. However, immune reconstitution and infection incidence after PTCy-based versus conventional GVHD prophylaxis has not been well studied. We evaluated the infection density and immune reconstitution (ie, absolute CD4+ T cell, CD8+ T cell, natural killer cell, and B cell counts) at 3 months, 6 months, and 1 year post-HCT in 583 consecutive adult patients undergoing allo-HCT with myeloablative (n = 223) or reduced-intensity (n = 360) conditioning between 2012 and 2018. Haploidentical (haplo; n = 75) and 8/8 HLA-matched unrelated (MUD; n = 08) donor types were included. GVHD prophylaxis was PTCy-based in all haplo (n = 75) and in 38 MUD allo-HCT recipients, whereas tacrolimus/methotrexate (Tac/MTX) was used in 89 and Tac/Sirolimus (Tac/Sir) was used in 381 MUD allo-HCT recipients. Clinical outcomes, including infections, nonrelapse mortality (NRM), relapse, and overall survival (OS), were compared across the 4 treatment groups. The recovery of absolute total CD4+ T-cell count was significantly lower in the haplo-PTCy and MUD-PTCy groups compared with the Tac/MTX and Tac/Sir groups throughout 1 year post-allo-HCT (P = .025). In contrast, CD19+ B-cell counts at 6 months and thereafter were higher in the haplo-PTCy and MUD-PTCy groups compared with the Tac/MTX and Tac/Sir groups (P < .001). Total CD8+ T cell and NK cell recovery was not significantly different among the groups. Infection density analysis showed a significantly higher frequency of total infections in the haplo-PTCy and MUD-PTCy groups compared with the Tac/MTX and Tac/Sir groups (5.0 and 5.0 vs 1.8 and 2.6 per 1000-person days; P < .01) within 1 year of allo-HCT. The cumulative incidence of cytomegalovirus reactivation/infection at 1 year post-allo-HCT was higher in the haplo-PTCy group (51%) compared with the MUD-PTCy (26%), Tac/MTX (26%), or Tac/Sir (13%) groups (P < .001). The incidence of BK, human herpesvirus 6, and other viruses were also higher in the PTCy-based groups. Overall, the treatment groups had similar 2 year NRM (P = .27) and OS (P = .78) outcomes. Our data show that PTCy-based GVHD prophylaxis is associated with delayed CD4+ T cell but faster B cell immune reconstitution and a higher frequency of infections compared with conventional GVHD prophylaxis but has no impact on nonrelapse mortality or overall survival.