Pembrolizumab in relapsed or refractory primary mediastinal large B-cell lymphoma: final analysis of KEYNOTE-170.

Previous analyses of the phase 2 KEYNOTE-170 (NCT02576990) study demonstrated effective antitumor activity and acceptable safety of pembrolizumab 200 mg given every 3 weeks for up to 35 cycles (∼2 years) in patients with relapsed/refractory (R/R) primary mediastinal B-cell lymphoma (PMBCL) whose disease progressed after or who were ineligible for autologous stem cell transplantation. The end points included objective response rate (ORR), progression-free survival (PFS), and duration of response (DOR) according to the investigator per 2007 Response Criteria; overall survival (OS); and safety. In this final analysis, median duration of follow-up was 48.7 months (range, 41.2-56.2). The ORR was 41.5% (complete response, 20.8%; partial response, 20.8%). The median DOR was not reached; no patients who achieved a complete response progressed at the data cutoff. The median PFS was 4.3 months; the 4-year PFS rate was 33.0%. The median OS was 22.3 months; the 4-year OS rate was 45.3%. At the data cutoff, 30 patients (56.6%) had any-grade treatment-related adverse events (AEs); the most common were neutropenia, asthenia, and hypothyroidism. Grade 3/4 treatment-related AEs occurred in 22.6% of the patients; no grade 5 AEs occurred. After 4 years of follow-up, pembrolizumab continued to provide durable responses, with promising trends for long-term survival and acceptable safety in R/R PMBCL.

Glofitamab in relapsed/refractory diffuse large B-cell lymphoma: Real-world data.

Glofitamab is a CD3xCD20 bi-specific antibody with two fragments directed to the CD20 antigen and a single CD3-binding fragment. Encouraging response and survival rates were recently reported in a pivotal phase II expansion trial conducted in patients with relapsed/refractory (R/R) B-cell lymphoma. However, the real-world data of patients of all ages with no strict selection criteria are still lacking. Herein, this retrospective study aimed to evaluate the outcomes of diffuse large B-cell lymphoma (DLBCL) patients who received glofitamab via compassionate use in Turkey. Forty-three patients from 20 centers who received at least one dose of the treatment were included in this study. The median age was 54 years. The median number of previous therapies was 4, and 23 patients were refractory to first-line treatment. Twenty patients had previously undergone autologous stem cell transplantation. The median follow-up time was 5.7 months. In efficacy-evaluable patients, 21% and 16% of them achieved complete response and partial response, respectively. The median response duration was 6.3 months. The median progression-free survival (PFS) and overall survival (OS) was 3.3 and 8.8 months, respectively. None of the treatment-responsive patients progressed during the study period, and their estimated 1-year PFS and OS rate was 83%. The most frequently reported toxicity was hematological toxicity. Sixteen patients survived, while 27 died at the time of the analysis. The most common cause of death was disease progression. One patient died of cytokine release syndrome during the first cycle after receiving the first dose of glofitamab. Meanwhile, two patients died due to glofitamab-related febrile neutropenia. This is the largest real-world study on the effectiveness and toxicity of glofitamab treatment in R/R DLBCL patients. The median OS of 9 months seems promising in this heavily pretreated group. The toxicity related mortality rates were the primary concerns in this study.

Posttransplant cyclophosphamide-based anti-graft-vs-host disease prophylaxis in patients with acute lymphoblastic leukemia treated in complete remission with allogeneic hematopoietic cell transplantation from human leukocyte antigen-mismatched unrelated donors versus haploidentical donors: A study on behalf of the ALWP of the EBMT.

BACKGROUND: Both mismatched unrelated donor (MMUD) and haploidentical (haplo) transplantation are valid options in patients with high-risk acute lymphoblastic leukemia (ALL) lacking a matched donor. METHODS: The study compared the outcomes of adult patients with ALL in complete remission (CR) who underwent 9/10 MMUD versus haplo transplantation with posttransplant cyclophosphamide (PTCy) as graft-vs-host disease (GVHD) prophylaxis in 2010-2020. RESULTS: The study included 781 patients (MMUD, 103; haplo, 678). The median age was 40 (19-73) and 38 (18-75) years, respectively (p = .51). The most frequent immunosuppression agents added to PTCy were mycophenolate mofetil (MMF)/cyclosporine A and MMF/tacrolimus. In vivo T-cell depletion (anti-thymocyte globulin) was administered to 21% and 8% of the transplants, respectively (p < .0001). Neutrophil (absolute neutrophil count >0.5 × 109 /L) recovery was achieved in 97.1% versus 96.7% versus (p = 1) in MMUD and haplo, respectively. Nonrelapse mortality and relapse incidence were not significantly different between MMUD and haplo, hazard ratio (HR) = 1.45 (95% confidence interval [CI], 0.81-2.62; p = .21) and HR = 0.81 (95% CI, 0.52-1.28, p = .38), respectively. HRs for leukemia-free survival, overall survival, and GVHD-free, relapse-free survival were respectively, HR = 1.05 (95% CI, 0.73-1.50, p = .8), HR = 1.17 (95% CI, 0.77-1.76, p = .46), and HR = 1.07 (95% CI, 0.78-1.46, p = .7) for haplo compared to MMUD. Acute (a)GVHD grade 2-4 was significantly higher with haplo, HR = 1.73 (95% CI, 1.08-2.76, p = .023), whereas aGVHD grade 3-4 and chronic GVHD did not differ significantly between the two transplant groups. CONCLUSION: Outcomes of MMUD and haplo transplants with PTCy-based GVHD prophylaxis for ALL patients in CR are similar, apart from a higher incidence of aGVHD with haplo transplants.

An Anomaly with Potential as a New Prognostic Marker in CLL with del(13q): Gain of 16p13.3.

Deletion 13q [del(13q)] is a favorable prognostic marker if it is detected as a sole abnormality in chronic lymphocytic leukemia (CLL). However the clinical courses of cases with isolated del(13q) are quite heterogeneous. In our study, we investigated copy number variations (CNVs), loss of heterozygosity (LOH), and the size of del(13q) in 30 CLL patients with isolated del(13q). We used CGH+SNP microarrays in order to understand the cause of this clinical heterogeneity. We detected del(13q) in 28/30 CLL cases. The size of the deletion varied from 0.34 to 28.81 Mb, and there was no clinical effect of the deletion size. We found new prognostic markers, especially the gain of 16p13.3. These markers have statistically significant associations with short time to first treatment and advanced disease stage. Detecting both CNVs and LOH at the same time is an advantageous feature of aCGH+SNP. However, it is very challenging for the array analysis to detect mosaic anomalies. Therefore, it is very important to confirm the results by FISH. In our study, we detected approximately 9% mosaic del(13q) by microarray. In addition, the gain of 16p13.3 may affect the disease prognosis in CLL. However, additional studies with more patients are needed to confirm these results.

Post-transplant cyclophosphamide versus anti-thymocyte globulin for graft-versus-host disease prevention in haploidentical transplantation for adult acute lymphoblastic leukemia.

Graft-versus-host disease (GVHD) prophylaxis for unmanipulated haploidentical hematopoietic cell transplantation (haplo-HCT) include post-transplant cyclophosphamide (PTCy) and anti-thymocyte globulin (ATG). Utilizing EBMT registry, we compared ATG versus PTCy based GVHD prophylaxis in adult acute lymphoblastic leukemia (ALL) patients undergoing haplo-HCT. Included were 434 patients; ATG (n=98) and PTCy (n=336). Median follow-up was ~2 years. Baseline characteristics were similar between the groups except that the ATG-group was more likely to have relapsed/refractory ALL (P=0.008), non-TBI conditioning (P<0.001), peripheral blood graft source (P=<0.001) and transplanted at an earlier time-period (median year of HCT 2011 vs. 2015). The 100-day grade II-IV and III-IV acute-GVHD was similar between ATG and PTCy, as was 2-year chronic-GVHD. On multivariate analysis (MVA), leukemia-free survival (LFS) and overall survival (OS) was better with PTCy compared to ATG prophylaxis. Relapse incidence (RI) was lower in the PTCy group (P=0.03), while non-relapse mortality (NRM) was not different. Advanced disease and lower performance score were associated with poorer LFS and OS and advanced disease with inferior GVHD-free/relapse-free survival (GRFS). Peripheral grafts were associated with higher GVHD compared to bone marrow grafts. In ALL patients undergoing unmanipulated haplo-HCT, PTCy for GVHD prevention resulted in lower RI and improved LFS and OS compared to ATG.

Role of Therapeutic Plasma Exchange in Guillain-Barre Syndrome after Allogeneic Hematopoietic Stem Cell Transplant: Report of Two Cases.

BACKGROUND: Guillain-Barre Syndrome (GBS) is an acute inflammatory polyneuropathy characterized with rapid, progressive, ascending, and symmetrical weakness and areflexia. It is supposed to be an autoimmune disease related with production of antibodies by T lymphocytes activated against antigenic proteins of the peripheral nerves. Guillain-Barre Syndrome occurring after hematopoietic stem cell transplant (HSCT) has been associated with viral infections or toxic effects of chemotherapy. METHODS: We report two GBS cases after HSCT treated successfully by means of therapeutic plasma exchange. RESULTS: In a total of 257 patients, 2 cases (0.8%) were diagnosed with GBS following HSCT. Allogeneic HSCT was performed and complete remission was achieved. Diagnosis of GBS was established on the 45th and 69th days with respect to clinical, cerebrospinal fluid, and electromyography findings. Patients did not respond to treatment consisting of intravenous immunoglobulins (IVIG) (1 g/kg/day) for 2 days and methylprednisolone (1 g/kg/day). Mechanical ventilation was indicated in one patient due to the involvement of respiratory muscles. Therapeutic plasma exchange resulted in complete recovery in both cases. CONCLUSIONS: Guillain-Barre Syndrome is a rare but serious complication, which may occur after HSCT. Increased awareness and early diagnosis are crucial in the management of GBS. First line treatment consists of IVIG and steroids and therapeutic plasma exchange must be considered without delay in refractory cases.

Haploidentical Transplantation with Post-Transplantation Cyclophosphamide for T Cell Acute Lymphoblastic Leukemia: A Report from the European Society for Blood and Marrow Transplantation Acute Leukemia Working Party.

Allogeneic hematopoietic cell transplantation (HCT) is recommended in high-risk patients with T cell acute lymphoblastic leukemia (T-ALL). For patients without an HLA-identical donor, haploidentical (haplo-) HCT is becoming the leading source of stem cell donation. However, data are scarce on predictive factors for outcome in that setting. We identified 122 adults (20% female; median age, 31 years; range, 18 to 68 years) with T-ALL who underwent haplo-HCT with post-transplantation cyclophosphamide (ptCy) between 2010 and 2017. The median duration of follow-up of living patients was 23 months. The 2-year incidences of relapse and nonrelapse mortality were 45% and 21%, respectively. The 2-year leukemia-free survival (LFS), overall survival (OS), and graft-versus-host disease, relapse-free survival (GRFS) were 34%, 42%, and 27%, respectively. The 2-year LFS and OS were highly influenced by disease status at transplantation, being 49% and 55%, respectively, for patients in first complete remission (CR1); 34% and 50%, respectively, for those in second CR (CR2); and 8% and 12%, respectively, for patients with active disease. On multivariate analysis, only disease status was found to affect LFS and OS. Transplantation in CR2 negatively affected LFS, whereas active disease at the time of haplo-HCT negatively affected LFS and OS. In conclusion, haplo-HCT with ptCy produced encouraging results in this challenging disease, particularly when performed in patients in CR. Despite the limitation of the small sample size, our results were not affected by the type of conditioning, calling into question the need for total body irradiation-based myeloablative conditioning in that setting.

Influence of donor type, stem cell source and conditioning on outcomes after haploidentical transplant for lymphoma - a LWP-EBMT study.

Haploidentical stem cell transplantation (haploSCT) is becoming a major transplant modality for lymphoma. To assess the effects of donor characteristics, stem cell source and conditioning on outcomes, we identified 474 adults with Hodgkin (HL; 240), peripheral T-cell (PTCL; 88), diffuse large B-cell (77), mantle cell (40) or follicular lymphoma (FL; 29), who received haploSCT with post-transplant cyclophosphamide. Median follow-up of alive patients was 32 months. On multivariate analysis, acute graft-versus-host disease (GVHD) grade 2-4 was lower with offspring donors or bone marrow cells, whereas extensive chronic GVHD was higher in partial response at haploSCT or when using sisters, haploidentical donors beyond first degree, or female donors in male patients. Progression-free survival (PFS) was better for FL, HL and PTCL, whereas overall survival (OS) was better for HL and PTCL. Complete remission at haploSCT improved PFS and OS whereas these were negatively affected by cytomegalovirus donor positive/recipient positive status. No other donor characteristics (age, gender, human leucocyte antigen mismatch, ABO incompatibility) affected PFS or OS except use of haploidentical donors beyond first degree, which negatively affected OS. PFS and OS are mostly influenced by disease status and lymphoma subtype, supporting the use of any first degree haploidentical family member as a donor.

Nivolumab for relapsed or refractory Hodgkin lymphoma: real-life experience.

Classical Hodgkin lymphoma (cHL) is considered a curable disease; however, in approximately one-third of the responding patients, the disease relapses following completion of therapy. One of the drugs that have been approved for the treatment of relapsed/refractory cHL is nivolumab, an immune check point inhibitor that shows its effects by blocking the programmed death 1 (PD-1) receptor. In this study, we present a retrospective "real-life" analysis of the usage of nivolumab in patients with relapsed/refractory cHL that have joined the named patient program (NPP) for nivolumab, reflecting 4 years of experience in the treatment of relapsed/refractory cHL. We present a retrospective analysis of 87 patients (median age, 30) that participated in the NPP in 24 different centers, who had relapsed/refractory cHL and were consequently treated with nivolumab. The median follow-up was 29 months, and the median number of previous treatments was 5 (2-11). In this study, the best overall response rate was 70% (CR, 36%; PR, 34%). Twenty-eight of the responding patients underwent subsequent stem cell transplantation (SCT). Among 15 patients receiving allogeneic stem cell transplantation, 9 patients underwent transplantation with objective response, of which 8 of them are currently alive with ongoing response. At the time of analysis, 23 patients remained on nivolumab treatment and the rest discontinued therapy. The main reason for discontinuing nivolumab was disease progression (n = 23). The safety profile was acceptable, with only nine patients requiring cessation of nivolumab due to serious adverse events. The 24-month progression-free and overall survival rates were 58.5% (95% CI, 0.47-0.68) and 78.7% (95% CI, 0.68-0.86), respectively. Eighteen patients died during the follow-up and only one of these was regarded to be treatment-related. With its efficacy and its safety profile, PD-1 blockers became an important treatment option in the heavily pretreated cHL patients.

CD34+ cell dose effects on clinical outcomes after T-cell replete haploidentical allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia using peripheral blood stem cells. A study from the acute leukemia working Party of the European Society for blood and marrow transplantation (EBMT).

Previous observations have reported controversial conclusions regarding cell dose and survival endpoints after allogeneic hematopoietic stem cell transplantation (HSCT). We conducted a retrospective analysis on 414 adult patients (median age 54 years, range, 18-74 years) with acute myeloid leukemia (AML) in first and second complete remission. They received a T-cell replete allogeneic HSCT from haploidentical donors, using peripheral blood stem cells, between 2006-2018. Median number of infused CD34+ was 6.58 × 106 /kg (range, 2.2-31.2 × 106 /kg). Graft-vs-host disease (GVHD) prophylaxis was post-transplant cyclophosphamide in 293 patients and anti-lymphocyte serum in 121 patients. Conditioning was myeloablative in 179 patients and reduced-intensity in 235 patients. After a median follow-up of 23.3 months (range, 12.1-41.8 months), 2-year overall survival (OS) was 64.5% (95% CI 59.3%-69.7%) with leukemia-free survival (LFS) of 57.3% (95% CI 51.8%-62.7%) and non-relapse mortality (NRM) of 23.3% (95% CI 19%-27.7%). Grades III-IV acute GVHD day+100 incidence was 14.6% while extensive chronic GVHD was 14.4% at 2-years. Thirteen (3.2%) patients experienced graft failure. We found the optimal CD34+/kg threshold defining high (n = 334) vs low cell dose (n = 80) at 4.96 × 106 . Recipients of >4.96 × 106 /kg CD34+ cells experienced less NRM (Hazard ratio [HR] 0.48; 95% CI 0.30-0.76) and prolonged LFS (HR 0.63; 95% CI 0.43-0.91) and OS (HR 0.60; 95% CI 0.40-0.88) compared to those in the lower cell dose cohort. Larger cohort studies are needed to confirm these findings.