Long-term real-world outcomes of patients with acute promyelocytic leukaemia treated with arsenic trioxide and all-trans retinoic acid without chemotherapy-a retrospective, single-centre study.

Arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) form the backbone of the treatment of acute promyelocytic leukaemia (APL), with the addition of chemotherapy for high-risk patients. We describe our experience of treating patients with APL of all risk classes with ATO and ATRA without chemotherapeutic agents. Patients received induction with ATO and ATRA followed by three cycles of consolidation with ATO and ATRA (each 1 month apart) after achieving morphological remission. Patients with intermediate- and high-risk disease received a further 2 years of maintenance with ATRA, 6-mercaptopurine and methotrexate. A total of 206 patients were included in the study. The majority of the patients were intermediate risk (51.9%), followed by high risk (43.2%). Differentiation syndrome was seen in 41 patients (19.9%). Overall, 25 patients (12.1%) died within 7 days of initiating therapy. Seven patients relapsed during follow-up. The mean (SD) estimated 5-year event-free survival (EFS) and overall survival (OS) in the entire cohort was 79% [5.8%] and 80% [5.8%] respectively. After excluding patients who died within 7 days of therapy initiation, the mean (SD) estimated 5-year EFS and OS was 90% [5.8%] and 93% [3.9%] respectively. Our study shows that treatment of all risk classes of APL with ATO and ATRA without chemotherapy is associated with excellent long-term outcomes in the real-world setting.

Feasibility of treatment-free remission with generic imatinib: Results of generic imatinib-free trial-in-chronic myeloid leukaemia-chronic phase study.

Background & objectives: Both innovator and generic imatinib are approved for the treatment of Chronic Myeloid Leukaemia-Chronic phase (CML-CP). Currently, there are no studies on the feasibility of treatment-free remission (TFR) with generic imatinib. This study attempted to determine the feasibility and efficacy of TFR in patients on generic Imatinib. Methods: In this single-centre prospective Generic Imatinib-Free Trial-in-CML-CP study, twenty six patients on generic imatinib for ≥3 yr and in sustained deep molecular response (BCR ABLIS ≤0.01% for more than two years) were included. After treatment discontinuation, patients were monitored with complete blood count and BCR ABLIS by real-time quantitative PCR monthly for one year and three monthly thereafter. Generic imatinib was restarted at single documented loss of major molecular response (BCR ABLIS>0.1%). Results: At a median follow up of 33 months (interquartile range 18.7-35), 42.3 per cent patients (n=11) continued to be in TFR. Estimated TFR at one year was 44 per cent. All patients restarted on generic imatinib regained major molecular response. On multivariate analysis, attainment of molecularly undetectable leukaemia (>MR5) prior to TFR was predictive of TFR [P=0.022, HR 0.284 (0.096-0.837)]. Interpretation & conclusions: The study adds to the growing literature that generic imatinib is effective and can be safely discontinued in CML-CP patients who are in deep molecular remission.

Use of convalescent plasma for COVID-19 in India: A review & practical guidelines.

Convalescent plasma (CP) therapy is one of the promising therapies being tried for COVID-19 patients. This passive immunity mode involves separating preformed antibodies against SARS-CoV-2 from a recently recovered COVID-19 patient and infusing it into a patient with active disease or an exposed individual for prophylaxis. Its advantages include ease of production, rapid deployment, specificity against the target infectious agent, and scalability. In the current pandemic, it has been used on a large scale across the globe and also in India. However, unequivocal proof of efficacy and effectiveness in COVID-19 is still not available. Various CP therapy parameters such as donor selection, antibody quantification, timing of use, and dosing need to be considered before its use. The current review attempts to summarize the available evidence and provide recommendations for setting up CP protocols in clinical and research settings.

Randomized controlled trial of twice-daily versus alternate-day oral iron therapy in the treatment of iron-deficiency anemia.

Recent studies in iron-depleted women have challenged the current approach of treating iron-deficiency anemia (IDA) with oral iron in divided daily doses. Alternate day dosing leads to more fractional absorption of iron. In this randomized controlled trial, we looked at the efficacy and safety of alternate-day (AD) versus twice-daily (BD) oral iron in all severity of IDA. Total of 62 patients were randomized, 31 patients in BD arm received 60 mg elemental iron twice daily while 31 patients in AD arm received 120 mg iron on alternate days. The primary endpoint of 2 g/dl rise in hemoglobin was met in significantly more patients in the BD arm at 3 weeks (32.3% vs. 6.5%, p < 0.0001) and 6 weeks (58% vs. 35.5%, p = 0.001). There was a significant rise in the median hemoglobin at 3 (1.6 vs. 1.1, p = 0.02) and 6 weeks (2.9 vs. 2.0 g/dl, p = 0.03) in the BD arm. However, the median hemoglobin rise in the AD arm at 6 weeks was not significantly different than the BD arm at 3 weeks. Alternate-day dosing for 6 weeks and twice-daily dosing for 3 weeks resulted in the provision of the same total amount of iron. There were more reports of nausea in the BD arm (p = 0.03). In conclusion, the choice of twice-daily or alternate-day oral iron therapy should depend on the severity of anemia, the rapidity of response desired, and patient preference to either regimen due to adverse events. Trial Registration: CTRI reg. no. CTRI/2018/07/015106 http://ctri.nic.in/Clinicaltrials/login.php.

Quality of life in patients of chronic lymphocytic leukemia using the EORTC QLQ-C30 and QLQ-CLL17 questionnaire.

INTRODUCTION: The quality of life (QoL) analysis is likely to differ by region, ethnicity, and questionnaires in comparison with age-matched healthy controls. METHODS: The EORTC QLQ-C30 and QLQ-CLL17 questionnaire validated in regional languages were administered to 127 consecutive CLL and 100 age-matched, healthy controls at a single center from 2018 to 2019. RESULTS: All groups of CLL patients either on wait and watch (W&W) or on treatment had significantly impaired QoL in all functional domains including global health compared to controls (P < .0001). CLL patients had significantly higher symptom scores than controls in most domains (P < .0001, 0.03 for diarrhea). There was no difference in the QoL by age or gender. Lower socioeconomic status patients had higher financial difficulty (P = .02). Patients on CIT had the worst global health (OR 12.21 compared to patients on W&W) (P = .03). Patients on ibrutinib had less worries/fears about health and functioning than patients who were on CIT (P = .04). CONCLUSIONS: Quality of life is severely affected in CLL patients on W&W. Global health status and worries about future health and functioning were major concerns. Socioeconomic status but not age or gender impacted QoL. Patients on ibrutinib had better QoL than on CIT.

Fludarabine melphalan versus fludarabine treosulfan for reduced intensity conditioning regimen in allogeneic hematopoietic stem cell transplantation: a retrospective analysis.

Various reduced-intensity conditioning (RIC) regimens are used to decrease toxicity while providing comparable outcomes to myeloablative regimens. We compared toxicity and outcomes between two RIC regimens, fludarabine with melphalan (Flu-Mel) and fludarabine with treosulfan (Flu-Treo), retrospectively over a 10-year period in two donor groups, matched related donor (MRD)/matched unrelated donor (MUD) and haploidentical (Haplo) transplants. The study included 138 patients, of which 105 received MRD/MUD (Flu-Mel: 94, Flu-Treo: 11) and 33 Haplo (Flu-Mel: 17, Flu-Treo: 16) transplants. In the MRD/MUD group, 44 (47%) of patients who received Flu-Mel had grade 3/4 oral mucositis compared to 1 (9%) who received Flu-Treo (P = 0.02). Corresponding numbers in the Haplo group were 7 (41%) and 1 (6%). Grade 3/4 diarrhoea was more frequent with Flu-Mel than Flu-Treo in the Haplo group (41% vs 6%; P = 0.039), but not the MRD/MUD group. Median follow-up time for all patients was 4.8 years. Five-year OS in the MRD/MUD group was 62% with Flu-Mel versus 53% with Flu-Treo (P = 0.0694). Similarly, 5-year OS was 41% with Flu-Mel and 28% with Flu-Treo (P = 0.770) in the Haplo group. Severe mucositis and diarrhoea were significantly less frequent with Flu-Treo than Flu-Mel. Flu-Treo provided comparable outcomes to Flu-Mel in all donor transplants.

Withania Somnifera Extract Mitigates Experimental Acute Graft versus Host Disease Without Abrogating Graft Versus Leukemia Effect.

Acute graft versus host disease (aGvHD) is the major contributor of nonrelapse mortality in alloHSCT. It is associated with an inflammatory immune response manifesting as cytokine storm with ensuing damage to target organs such as liver, gut, and skin. Prevention of aGvHD while retaining the beneficial graft versus leukemia (GvL) effect remains a major challenge. Withania somnifera extract (WSE) is known for its anti-inflammatory, immune-modulatory, and anticancer properties, which are appealing in the context of aGvHD. Herein, we demonstrated that prophylactic and therapeutic use of WSE in experimental model of alloHSCT mitigates aGvHD-associated morbidity and mortality. In the prophylaxis study, a dose of 75 mg/kg of WSE offered greatest protection against death due to aGvHD (hazard ratio [HR] = 0.15 [0.03-0.68], P ≤ .01), whereas 250 mg/kg was most effective for the treatment of aGvHD (HR = 0.16 [0.05-0.5], P ≤ .01). WSE treatment protected liver, gut, and skin from damage by inhibiting cytokine storm and lymphocytic infiltration to aGvHD target organs. In addition, WSE did not compromise the GvL effect, as alloHSCT with or without WSE did not allow the leukemic A20 cells to grow. In fact, WSE showed marginal antileukemic effect in vivo. WSE is currently under clinical investigation for the prevention and treatment of aGvHD.

Circulating tumor plasma cells and peripheral blood measurable residual disease assessment in multiple myeloma patients not planned for upfront transplant.

Circulating tumor plasma cells (CTPCs) provide a noninvasive alternative for measuring tumor burden in newly diagnosed multiple myeloma (NDMM). Moreover, measurable residual disease (MRD) assessment in peripheral blood (PBMRD) can provide an ideal alternative to bone marrow MRD, which is limited by its painful nature and technical challenges. However, the clinical significance of PBMRD in NDMM still remains uncertain. Additionally, data on CTPC in NDMM patients not treated with transplant are scarce. We prospectively studied CTPC and PBMRD in 141 NDMM patients using highly sensitive multicolor flow cytometry (HS-MFC). PBMRD was monitored at the end of three cycles (PBMRD1) and six cycles (PBMRD2) of chemotherapy in patients with detectable baseline CTPC. Patients received bortezomib-based triplet therapy and were not planned for an upfront transplant. Among baseline risk factors, CTPC ≥ 0.01% was independently associated with poor progression-free survival (PFS) (hazard ratio [HR] = 2.77; p = 0.0047) and overall survival (OS) (HR = 2.9; p = 0.023) on multivariate analysis. In patients with detectable baseline CTPC, undetectable PBMRD at both subsequent time points was associated with longer PFS (HR = 0.46; p = 0.0037), whereas detectable PBMRD at any time point was associated with short OS (HR = 3.25; p = 0.004). Undetectable combined PBMRD (PBMRD1 and PBMRD2) outperformed the serum-immunofixation-based response. On multivariate analysis, detectable PBMRD at any time point was independently associated with poor PFS (HR = 2.0; p = 0.025) and OS (HR = 3.97; p = 0.013). Thus, our findings showed that CTPC and PBMRD assessment using HS-MFC provides a robust, noninvasive biomarker for NDMM patients not planned for an upfront transplant. Sequential PBMRD monitoring has great potential to improve the impact of the existing risk stratification and response assessment models.

Carfilzomib-induced Thrombotic Microangiopathy: A Case Based Review.

Carfilzomib is an irreversible proteasome inhibitor currently approved for the treatment of relapsed multiple myeloma. It has been implicated as a cause of thrombotic microangiopathy (TMA) in several case reports. The incidence, risk factors, and treatment of carfilzomib-related TMA remain unclear. Here we describe the clinical presentation and outcome of a 58-year-old man with biopsy-proven TMA that occurred following treatment with carfilzomib-based therapy. We also reviewed the published literature with regard to the incidence, risk factors, treatment options, and outcome of carfilzomib-related TMA.

Monocyte Distribution Width (MDW) in Patients with COVID-19: An Indicator of Disease Severity.

Identifying patients with Coronavirus disease-2019 (COVID-19) who may have a severe illness is essential for timely intervention and decreasing the fatality rate. In the present study, we evaluated the performance of Monocyte Distribution Width (MDW) as a prognostic marker for identifying disease severity in COVID-19 patients. We included 145 patients with PCR-confirmed COVID-19 infection in the study. The performance of MDW was evaluated by calculating the area under the receiver operating characteristic curve (AUC), specificity, sensitivity, negative predictive value, and positive predictive value. Further analysis was conducted for the disease outcome, comparing COVID-19 patients discharged (n = 135) to deceased COVID-19 patients (n = 10). As a marker of disease severity, MDW demonstrated an AUC of 0.702 (95% CI 0.620-0.775) in ROC analysis. If MDW is considered a marker of patient outcome, AUC was 0.916 (95% CI 0.862-0.953), comparing deceased COVID-19 patients vs. those who survived. At a cut-off of > 25.4 on admission, MDW correlates well with poor disease outcomes in COVID-19 patients. MDW can be considered a helpful parameter in predicting the severity of COVID-19 disease and patient outcomes. Its role and incorporation in the standard diagnostic algorithm and management of COVID-19 patients need further validation. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-023-01665-y.

Lenalidomide with or without dexamethasone for relapsed or refractory Hodgkin lymphoma post autologous stem cell transplant.

Background: The prognosis of Hodgkin lymphoma (HL) relapsing post autologous transplant (AuSCT) is poor. Even with novel therapies, only approximately 20%-25% of patients attain complete remissions, with a median progression-free survival (PFS) of approximately 5-15 months. Lenalidomide has been shown to have activity in relapsed HL. We retrospectively analyzed the outcomes of patients with relapsed HL post AuSCT treated with lenalidomide alone or in combination with dexamethasone at our center. Patients and methods: Records of 143 patients transplanted from November 2007 to October 2021 were reviewed. Of these patients, 41 (28%) relapsed, and 16 (39%) received lenalidomide alone or in combination with dexamethasone. Data collected included demographic, pathological, staging, and prior therapy details. Lenalidomide was administered at 10-25 mg/day on an intermittent or continuous schedule alone or in combination with dexamethasone (20-40 mg weekly). Response was assessed using PET-CT scan in accordance with Lugano criteria. Standard definitions were used for response, PFS, and overall survival (OS). Toxicities were graded using Common Terminology Criteria for Adverse Events version 5.0. Statistical analysis was done using SPSS Version 21. Results: The median age of the patients was 25.5 years, and 10 were males. Eleven (69%) had advanced disease, and 7 (44%) were refractory to last systemic therapy. Nine patients received lenalidomide alone and 7 with dexamethasone. Four (25%) had complete response, and another four (25%) had partial response, with an overall response rate of 50%. The 3-year PFS and OS were 31% and 38%, respectively. Grade III/IV toxicities were only hematological, neutropenia and thrombocytopenia in four and three patients, respectively. No therapy-related deaths were recorded. Conclusions: Lenalidomide alone or in combination with dexamethasone is a safe and effective therapy for relapsed HL post AuSCT and results in durable response and long-term survival in approximately one-third of the patients. However, these results needs verification in larger prospective studies.

Relevance of vitamin D in patients undergoing HLA matched allogeneic stem cell transplant for acute leukemia.

BACKGROUND: In hematopoietic stem cell transplant (HSCT), vitamin D deficiency has been variably associated with increased complications, primarily graft versus host disease (GvHD), with a potential impact on survival. Results from various studies however, have not been consistent. This analysis was conducted to study the impact of peri-transplant vitamin D levels on transplant outcomes in patients with acute leukemia (AL) who underwent HLA matched (related/unrelated) HSCT. METHODS: This was a single center retrospective study. Patients of AL including Acute Lymphoblastic Leukemia (ALL), Acute Myeloid Leukemia (AML) or Mixed Phenotypic Acute Leukemia (MPAL) who underwent fully matched or 9/10 transplants (related/unrelated) between 2008 and 2019 were included. Vitamin D deficiency was defined as serum 25-hydroxy vitamin D3 levels ≤20 ng/ml. Those with deficiency received replacement with oral vitamin D at a dose of 60,000 IU weekly for 8 weeks followed by maintenance with daily vitamin D (800 IU/day). Vitamin D levels were repeated at 4 months from start of replacement. For patients who received correction, repeat levels >20 ng/ml were considered replete. Based on vitamin D levels in the peri-transplant period (within 120 days of transplant), patients were categorised as either vitamin D replete (> 20 ng/ml) or deplete (≤ 20 ng/ml). Peri-transplant vitamin D status was correlated with transplant outcomes. RESULTS: Of the 133 patients included, 31 were deplete (median vitamin D 15.0 ng/ml) and 102 were replete (median vitamin D 34 ng/ml) at time of transplant. Both groups were matched for age, diagnosis, EBMT score and disease risk index (DRI). There were no differences in time to neutrophil or platelet engraftment, CMV reactivation, acute GvHD (aGvHD) or chronic GvHD (cGvHD) between the two groups. Relapse rate, Progression Free Survival (PFS) and Overall Survival (OS) were also comparable between the 2 groups. CONCLUSION: The incidence of vitamin D deficiency was high in our patient cohort. Patients who were vitamin D deficient at the time of transplant did not have inferior outcomes, suggesting a limited role of vitamin D in influencing transplant outcomes.

Comparison of Outcomes of Donor Lymphocyte Infusions With or Without Lenalidomide in Patients with Hematological Malignancies Post Allogeneic HSCT.

Outcomes with DLI alone for post-transplant relapsed hematological malignancies are poor especially in acute leukemias. Addition of immunomodulatory drugs to DLI may augment GVL effect. Use of lenalidomide with DLI to augment GVL has not been previously reported. This retrospective analysis was to compare the outcomes of DLI with or without lenalidomide. All consecutive patients who received DLI from 01/2010 through 01/2020 were included. DLIs were given without any immunosuppression. Lenalidomide, when used, was given continuously, starting with 1st or subsequent DLI. Patients who received lenalidomide were compared with those who did not. Event (hematological relapse or death) free survival (EFS) and overall survival (OS) were calculated from 1st DLI. Primary objective was to compare OS. Secondary objectives were EFS, CR rates, acute GVHD, lenalidomide toxicities and DLI related mortality (TRM). Total 61 patients received DLI-43 without and 18 with lenalidomide; all outcomes in the 2 groups were similar. There were 26 patients with HLA-A*24 and/or HLA-B*40. Among these, trend towards improvement in OS (median OS not reached vs. 8 months, 4 year OS was 62% vs. 32%, p = 0.1) and EFS (median 9 vs. 1 month, 4 year EFS 50% vs. 22%, p = 0.1) was seen with lenalidomide. Overall, there was no improvement in outcomes by adding lenalidomide to DLI. However, among patients with HLA*24 or B*40, there was a trend to improved survival with lenalidomide. Use of lenalidomide to augment the GVL effect of DLI warrants further exploration.

Factors associated with thrombo-hemorrhagic deaths in patients with Acute Promyelocytic leukemia treated with Arsenic Trioxide and all-trans retinoic acid.

Acute Promyelocytic Leukemia (APL) is associated with excellent long-term outcomes. However, early mortality due to coagulopathy remains a challenge. In this study we examined the bleeding and thrombotic manifestations, as well as incidence of Early Death secondary to thrombosis/hemorrhage (ED-TH) in patients with APL. Early death (ED) was defined as death occurring within 30 days of induction therapy. Two-hundred forty-eight patients were included in the study. Overall, 57 patients had evidence of a major bleed/thrombosis at presentation or during induction therapy, including 44 patients with a major bleed, 8 patients with thrombosis and 5 patients with both evidence of thrombosis and a major bleed. Forty patients (16.1%) had ED, of which 21 had ED-TH. The cumulative incidence of death due to thrombo-hemorrhagic complications at 30 days was 8.4%. On univariate analysis, increasing Prothrombin time (PT)(p-<0.001), white blood cell count (p < 0.001) and activated Partial thromboplastin time (aPTT) (p < 0.001) were statistically significantly associated with increased risk of ED-TH. However, on multivariate analysis, only increasing PT (p-0.025) and aPTT (p-0.041) were significantly associated with increased risk of ED-TH.

Low levels of CD26 on certain cellular subtypes of donor harvest is associated with better clinical outcomes post allogeneic stem cell transplantation through regulation of NF-κB pathway and pro-inflammatory cytokines.

BACKGROUND: We had previously reported significant association of immunoectoenzyme CD26 expression on donor harvest with acute Graft-versus-Host-Disease (aGVHD) in allogeneic stem cell transplantation (ASCT) patients. The current study was aimed at analysing CD26 signaling pathway molecules and understanding their impact on immune reconstitution and clinical outcomes post-ASCT. SUBJECTS AND METHODOLOGY: The study cohort included 26 transplant donors/patients who underwent reduced intensity (n = 21), myeloablative (n = 4) and non-myeloablative (n = 1) ASCT for hematological malignancies. Donors were matched related donors (n = 19) and haploidentical donors (n = 7). Surface expression of CD26, CD73 and ADA, and various immune cell subtypes were assessed by multicolour-flow cytometry. Soluble CD26 (sCD26) and cytokine levels were measured in plasma samples by ELISA and Multiplex Luminex assay, respectively. Immune cells from healthy individuals were stimulated with phytohemagglutinin (PHA) in the presence or absence of CD26 inhibitor. Effect of CD26 inhibition on NF-κB localization in PHA stimulated cells was analysed by immunofluorescence and confocal microscopy. Pro-inflammatory cytokines from the culture supernatants were detected with Cytometric bead array flow cytometry. Association of all measured markers with clinical outcomes was evaluated using appropriate statistical tests. RESULTS: CD26 surface expression on PBSC donor harvest cells showed increased risk of chronic GVHD (cGVHD, p = 0.055). Amongst the various immune cell subtypes, decreased B cells in harvest showed significant association with aGVHD (p = 0.022) whereas increased myeloid dendritic cells and CD3+T cells at Day100 in peripheral blood of transplant recipients correlated with cGVHD (p = 0.046) and aGVHD (p = 0.035), respectively. Further, high sCD26 in transplant recipients at Day100 exhibited association with reduced event-free survival (EFS) (p = 0.011). Higher CD26 expression on more & less mature NK cells, naïve & post-switched memory B cells and Treg cells in the donor harvest (p < 0.05) led to lower EFS in transplant recipients. Mechanistically, CD26 inhibitor caused dose-dependent reduction in CD26 enzyme activity and in pro-inflammatory cytokine production in post mitogen-stimulated T cell cultures. CONCLUSION: Our study has implicated that lower CD26 expression on immune cell subtypes of the donor stem cell harvest is associated with reduced risk of GVHD and better survival. The underlying mechanism was found to be through NF-κB pathway and pro-inflammatory cytokines. Based on these observations, chemically designed or natural resources-based CD26 inhibitors can be explored further in clinical trials for improving ASCT outcomes.

Withaferin-A alleviates acute graft versus host disease without compromising graft versus leukemia effect.

Acute graft versus host disease (aGvHD) contributes to a significant proportion of non-relapse mortality and morbidity in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT). Withaferin-A (WA), a phytomolecule obtained from Withania somnifera (Ashwagandha), is known to have anti-inflammatory, anti-proliferative and immunomodulatory properties. The efficacy of WA for the prevention and treatment of aGvHD was evaluated using a murine model of alloHSCT. Prophylactic administration of WA to mice mitigated the clinical symptoms of aGvHD and improved survival significantly compared to the GvHD control [HR = 0.07 (0.01-0.35); P < 0.001]. Furthermore, WA group had better overall survival compared to standard prophylactic regimen of CSA + MTX [HR = 0.19 (0.03-1.1), P < 0.05]. At the same time, WA did not compromise the beneficial GvL effect. In addition, WA administered to animals after the onset of aGvHD could reverse the clinical severity and improved survival, thus establishing its therapeutic potential. Our findings suggest that WA reduced the systemic levels of Th1, Th2 and Th17 inflammatory cytokine and increased the anti-inflammatory cytokine IL-10 levels significantly (P < 0.05). WA also inhibited lymphocytes migration to gut, liver, skin and lung and protected these organs from damage. Ex-vivo, WA inhibited proliferation of human peripheral blood mononuclear cells (hPBMCs), modulated immune cell phenotype and decreased cytokine release. In addition, WA inhibited pJAK2 and pSTAT3 protein levels in mouse splenocytes and hPBMCs. In conclusion, our study demonstrates the utility of WA for the prevention and treatment of aGvHD, which should be further evaluated in a clinical setting.

Long-Term Cryopreservation of Peripheral Blood Stem Cell Harvest Using Low Concentration (4.35%) Dimethyl Sulfoxide with Methyl Cellulose and Uncontrolled Rate Freezing at -80 °C: An Effective Option in Resource-Limited Settings.

Long-term cryopreservation of peripheral blood stem cells (PBSCs) is highly useful in the setting of tandem/multiple transplantations or treatment of relapse in the autologous hematopoietic stem cell transplantation (HSCT) setting. Even in allogeneic HSCT, donor lymphocyte infusions may be stored for months to years if excess stem cells are collected from donors. Cryopreservation is a delicate, complex, and costly procedure, and higher concentrations of dimethyl sulfoxide (DMSO), a commonly used cryoprotectant, can be toxic to cells and cause adverse effects in the recipient during infusions. In this study, we examined the effect of long-term cryopreservation using 4.35% DMSO (as final concentration) with methyl cellulose and uncontrolled rate freezing in a mechanical freezer (-80 °C) on the viability and colony-forming ability of CD34+ human PBSCs. For patients undergoing autologous HSCT, PBSCs were cryopreserved using DMSO (final concentration of 4.35%) with methyl cellulose. The post-thaw viability of PBSCs was determined using Trypan blue exclusion and flow cytometry-based 7-amino-actinomycin-D (FC-7AAD) methods. Concentrations of CD34+ stem cells and immune cell subsets in post-thaw PBSC harvest samples were assessed using multicolor flow cytometry, and the clonogenic potential of post-thaw stem cells was studied using a colony-forming unit (CFU) assay. CD34+ stem cell levels were correlated with the prestorage CD34 levels using the Pearson correlation test. The viability results in the Trypan blue dye exclusion method and the flow cytometry-based method were compared using Bland-Altman plots. We studied 26 PBSC harvest samples with a median cryopreservation duration of 6.6 years (range, 3.8 to 11.5 years). The median viability of post-thaw PBSCs was >80% using both methods, with a weak agreement between them (r = .03; P = .5). The median CD34+ stem cell count in the post-thaw samples was 9.13 × 106/kg (range, .44 to 26.27 × 106/kg). The CFU assay yielded a good proliferation and differentiation potential in post-thaw PBSCs, with a weak correlation between granulocyte macrophage CFU and CD34+ stem cell levels (r = .4; P = .05). Two samples that had been cryopreserved for >8 years showed low viability. Cryopreservation of PBSCs using 4.35% DMSO with methyl cellulose and uncontrolled freezing in a mechanical freezer at -80 °C allows the maintenance of long-term viability of PBSC for up to 8 years.

Randomized controlled trial of individualized, low dose, fixed duration lenalidomide maintenance versus observation after frontline chemo-immunotherapy in CLL.

Lenalidomide maintenance after frontline chemo-immunotherapy (CIT) in chronic lymphocytic leukemia (CLL) has not been standard due to the availability of novel therapies, though these remain out of reach for most in low-middle income countries. This single-center, open-label study randomized CLL patients (non-deletion 17p) after frontline therapy to lenalidomide maintenance (dose-escalated 2.5-10mg, 20/28 days per cycle for six months) or observation (2:1 allocation). Forty patients were included over 2018-2020. At a median follow-up of 22 months, median progression-free survival (PFS) with lenalidomide was not significantly different than observation (26 vs. 18 months, p = 0.4). Patients with minimal residual disease >10-2 had a trend toward better PFS with lenalidomide (19 vs. 7 months, p = 0.07). Grade 3 neutropenia was seen in 16.7% of patients on lenalidomide. Quality of life was comparable between the two arms. Low dose, fixed duration lenalidomide maintenance is not an effective strategy after frontline CIT in CLL.