Sigrid Machherndl-Spandl

Summary: B‐cell maturation antigen‐directed chimeric antigen receptor (CAR) T cells have revolutionized the treatment of relapsed/refractory multiple myeloma. However, no randomized head‐to‐head comparison of idecabtagene vicleucel (ide‐cel) and ciltacabtagene autoleucel (cilta‐cel) is available, and real‐world data suggest differences in efficacy and toxicity. We performed a nationwide retrospective real‐world analysis (RWA) of Austrian patients treated with ide‐cel or cilta‐cel between January 2024 and July 2025. Ninety patients were included, with largely balanced baseline characteristics and frequent high‐risk features. Bridging therapy was administered to 94.4% of patients, resulting in high response rates prior to lymphodepletion. After a median follow‐up of 17.6 months, no early separation of the progression‐free survival (PFS) curves was observed between CAR‐T products. Multivariable analyses showed a trend towards improved PFS with cilta‐cel, whereas true extra‐medullary disease (EMD) and prior bispecific antibody treatment before T‐cell apheresis were associated with inferior PFS. Although previous RWA have demonstrated an early divergence in PFS between cilta‐cel and ide‐cel, this pattern was not observed in our cohort. The high effectiveness of bridging therapy may have contributed to these findings. Our results support further investigation of optimal bridging strategies and treatment sequencing while highlighting the persistent unmet need of patients with true EMD.

Background: Pre-fibrotic myelofibrosis (pre-PMF) is a rare subentity of myeloproliferative neoplasm (MPN) with limited overall survival and the potential for progression toward overt, symptomatic myelofibrosis or blastic transformation. To date, a consensus on the treatment of pre-PMF, especially in asymptomatic cases, has yet to be reached. Interferon therapy has been employed as an effective treatment for MPN for many decades, due to its immunomodulatory properties and disease-modifying effects. Methods: The objective of this monocentric study was to evaluate hematological, molecular, and clinical responses, as well as the overall outcome, to pegylated interferon (peginterferon) in pre-PMF cases harboring a JAK2 or CALR mutation. Results: In a cohort of 55 consecutive patients with a median follow-up period of 3.89 (1.63; 6.10) years, a high rate of complete hematological response (81%) was documented after 24 months. Deep molecular responses with a >50% reduction in allele burden were documented in 54.6% of the JAK2-mutated and 7.7% of CALR-mutated patients, respectively (p = 0.023). Concerning fibrosis, at least the stabilization of disease was achieved in 73% of evaluable patients. Furthermore, only one case of blastic transformation was observed, along with three cases of thromboembolic events in the JAK2-mutated cohort. Conclusions: The study confirms the substantial efficacy of interferon in pre-PMF patients with rapid hematological normalization in most patients. Molecular responses were striking, but largely confined to JAK2-mutated patients. To our knowledge, this is the largest retrospective cohort of strictly WHO-defined pre-PMF patients treated with interferon and observed for a reasonable duration of time.

Background: T-prolymphocytic leukemia (T-PLL) is a rare lymphoid neoplasm with particularly poor prognosis. Although it is no longer recognized as a distinct entity by the World Health Organization (WHO), B-prolymphocytic leukemia (B-PLL) comprises conditions with unfavorable outcomes. Both diseases most frequently affect patients in the seventh decade of their lives. Allogeneic hematopoietic stem cell transplantation (alloHSCT) significantly improves outcomes for selected PLL cases, as shown by several, mostly retrospective, analyses. Methods: In this article, we provide a review of existing PLL analyses, followed by a summary of cases treated at our center. We describe outcomes of six T-PLL and three B-PLL cases receiving alloHSCT at our institution between 2015 and 2022. Results: Despite a post-transplant 4-year cumulative relapse incidence of 61% in our T-PLL series, the median OS was 78 months, because relapse therapy was remarkably successful. All B-PLL patients are alive and relapse-free, with a median follow-up of 54 (range of 11–74) months. A poor pre-transplant Karnofsky performance status (KPS) (≤ 80%) and an HCT comorbidity index (HCT-CI) of ≥3 were significantly associated with post-transplant mortality. Conclusions: The comparatively favorable outcomes in our case series underline the increasing value of alloHSCT in PLL in the current era, as it offers a prospect of cure in selected patients with otherwise very poor prognosis.

T-prolymphocytic leukemia (T-PLL) is a rare lymphoid neoplasm with particularly poor prognosis. B-prolymphocytic leukemia (B-PLL), although no longer recognized as a distinct entity by the World Health Organization (WHO), comprises conditions with unfavorable outcome as well. Both diseases most frequently affect patients in the 7th decade of their lives. Allogeneic hematopoietic stem cell transplantation (alloHSCT) significantly improves outcomes for selected PLL cases as shown by several, mostly retrospective, analyses. In this article, we provide a review of existing PLL analyses, followed by a summary of cases treated at our center. We describe outcomes of six T-PLL and three B-PLL cases receiving alloHSCT at our institution between 2015 and 2022. Despite a post-transplant 4-year cumulative relapse incidence of 61% in our T-PLL series, median OS was 78 months, because relapse therapy was remarkably successful. All B-PLL patients are alive and relapse-free with a median follow-up of 54 (range, 11 – 74) months. A poor pre-transplant Karnofsky performance score (<= 80) and an HCT Comorbidity Index (HCT-CI) of >= 3 were significantly associated with post-transplant mortality. The comparatively favorable outcomes in our case series underline the increasing value of alloHSCT in PLL in the current era, as it offers a prospect of cure in selected patients with otherwise very poor prognosis.

(1) Background: Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) is the only treatment with the potential for cure in patients with myelofibrosis (MF). However, the risk of graft rejection, which is particularly high in MF, and the risk of significant non-relapse mortality must be considered. (2) Methods: In this retrospective, single-center study, we compared allo-HSCT outcomes in 36 adult patients with MF transplanted at two-time intervals (2001–2015 versus 2016–2021). (3) Results: The estimated median overall survival was 48.9 months (95%CI 0.00–98.2) in the cohort transplanted before 2016 and not reached in the more recent years (p = 0.04) due to markedly lower non-relapse mortality (p = 0.02). The 3-year relapse incidence was low in both cohorts (11.1% and 12.5%, p > 0.99). When comparing only subgroups within the more recent cohort based on the presence or absence of total body irradiation (TBI) or the use of sequential regimens, OS and PFS were comparable. (4) Conclusion: Pretreatment with ruxolitinib, intensified conditioning, and the preferential use of haploidentical related instead of mismatched unrelated donors for patients lacking an HLA-identical donor are most likely responsible for the improved outcome after allo-HCT in MF in recent years.

Background: Despite major treatment advances, multiple myeloma remains incurable. The outcome of patients who are refractory to immunomodulatory agents, proteasome inhibitors, and anti-CD38 monoclonal antibodies is poor, and improved treatment strategies for this difficult-to-treat patient population are an unmet medical need. Methods: This retrospective, unicentric analysis included 38 patients with relapsed/refractory multiple myeloma or plasma cell leukemia who underwent allogeneic stem cell transplantation (allo-HSCT) between 2013 and 2022. Survival outcomes, relapse incidence, and non-relapse mortality were calculated according to remission status, date of allo-HSCT, cytogenetic risk status, timing, and number of previous autologous HSCTs. Results: The median PFS was 13.6 months (95% CI, 7.7–30.4) and the median OS was 51.4 months (95% CI, 23.5–NA) in the overall cohort. The cumulative incidence of relapse at 3 years was 57%, and non-relapse mortality was 16%. The median PFS and OS were significantly longer in patients with very good partial remission (VGPR) or better compared to patients with less than VGPR at the time of allo-HSCT (mPFS 29.7 months (95% CI, 13.7–NA) vs. 6.5 months (95% CI, 2.6–17.0); p = 0.009 and mOS not reached vs. 18.6 months (95% CI, 7.0–NA); p = 0.006). Conclusion: For selected patients, allo-HSCT may result in favorable overall survival, in part by providing an appropriate hemato-immunological basis for subsequent therapies.

(1) Background: mRNA COVID-19 vaccines are effective but show varied efficacy in immunocompromised patients, including allogeneic hematopoietic stem cell transplant (HSCT) recipients. (2) Methods: A retrospective study on 167 HSCT recipients assessed humoral response to two mRNA vaccine doses, using the manufacturer cut-off of ≥7.1 BAU/mL, and examined factors affecting non-response. (3) Results: Twenty-two percent of HSCT recipients failed humoral response. Non-responders received the first vaccine a median of 10.2 (2.5–88.9) months post-HSCT versus 35.3 (3.0–215.0) months for responders (p < 0.001). Higher CD19 (B cell) counts favored vaccination response (adjusted odds ratio (aOR) 3.3 per 100 B-cells/microliters, p < 0.001), while ongoing mycophenolate mofetil (MMF) immunosuppression hindered it (aOR 0.04, p < 0.001). By multivariable analysis, the time from transplant to first vaccine did not remain a significant risk factor. A total of 92% of non-responders received a third mRNA dose, achieving additional 77% seroconversion. Non-converters mostly received a fourth dose, with an additional 50% success. Overall, a cumulative seroconversion rate of 93% was achieved after up to four doses. (4) Conclusion: mRNA vaccines are promising for HSCT recipients as early as 3 months post-HSCT. A majority seroconverted after four doses. MMF usage and low B cell counts are risk factors for non-response.

Background: In allogeneic hematopoietic stem cell transplantation (HSCT), Anti-T-Lymphocyte Globulin (ATLG) may be used for the prevention of severe graft-versus-host disease (GVHD). ATLG targets both the recipient’s lymphocytes and those transferred with the graft. Assuming an inverse relation between the recipient’s absolute lymphocyte count (ALC) and exposure of remaining ATLG to the graft, we aim to evaluate the impact of the recipient’s ALC before the first ATLG administration on the benefits (prevention of GVHD and GVHD-associated mortality) and potential risks (increased relapse incidence) associated with ATLG. Methods: In recipients of HLA-matched, ATLG-based HSCT (n = 311), we assessed the incidence of acute GVHD, GVHD-related mortality and relapse, as well as other transplant-related outcomes, in relation to the respective ALC (divided into tertiles) before ATLG. Results: The top-tertile ALC group had a significantly increased risk of aGVHD (subhazard ratio (sHR) 1.81; [CI 95%; 1.14–2.88]; p = 0.01) and aGVHD-associated mortality (sHR 1.81; [CI 95%; 1.03–3.19]; p = 0.04). At the highest ATLG dose level (≥45 mg/kg), recipients with lowest-tertile ALC had a trend towards increased relapse incidence (sHR 4.19; [CI 95%; 0.99–17.7]; p = 0.05, n = 32). Conclusions: ATLG dosing based on the recipient’s ALC may be required for an optimal balance between GVHD suppression and relapse prevention.