Results of the compassionate program of inotuzumab ozogamicin for adult patients with relapsed or refractory acute lymphoblastic leukemia in Spain

INTRODUCTION

The prognosis of relapsed B cell precursor acute lymphoblastic leukemia (B-ALL) is poor and few patients can be successfully rescued with conventional therapies. Inotuzumab ozogamicin (IO), an antibody against the CD22 antigen linked to calicheamicin, has been approved as a rescue treatment in relapsed/refractory (R/R) B-ALL.

PATIENTS AND METHODS

This was an observational, retrospective, multicenter study of adult patients included in the Spanish program of compassionate use of IO in centers from the PETHEMA group (Programa Español de Tratamientos en Hematología).

RESULTS

Thirty-four patients with a median age of 43 years (range, 19-73) were included. Twenty patients (59%) were refractory to the last treatment, IO treatment was given as ≥3rd salvage treatment in 25 patients (73%) and 20 patients (59%) received allogeneic hematopoietic stem cell transplantation before IO treatment. After a median of 2 cycles of IO, 64% of patients achieved complete response (CR)/complete response with incomplete recovery. The median response duration, progression-free survival and overall survival (OS) were 4.7 (95%CI, 2.4-7.0 months), 3.5 (95%CI, 1.0-5.0 months) and 4 months (95%CI, 1.9-6.1 months) respectively, with better OS for patients with relapsed B-ALL versus refractory disease (10.4 vs. 2.5 months, respectively) (p = .01). There was a trend for better OS for patients with first CR duration >12 months (7.2 months [95%CI, 3.2-11.2] vs. 3 months [95% CI, 1.8-4.2] respectively) (p = .054). There was no sinusoidal obstruction syndrome (SOS) event during IO treatment, but three patients (9%) developed grade 3-4 SOS during alloHSCT after IO treatment.

CONCLUSIONS

Our study showed slightly inferior outcomes of the pivotal trial probably due to poorer risk factors and late onset of IO therapy of recruited patients. Our results support early use of IO in relapsed/refractory ALL patients.

Factors associated with quality of care in inflammatory bowel diseases: a view from patient's side using the IQCARO quality of care decalogue

Background

Quality of care (QoC) is a highly important topic in inflammatory bowel disease (IBD). We recently elaborated a decalogue of QoC indicators (IQCARO-QoC) developed by IBD patients. The aim of the present study was to assess the factors associated with patients’ evaluation of QoC in Spain using the IQCARO-QoC Decalogue recently developed by IBD patients.

Methods

A survey including patients’ socio-demographic and clinical characteristics, and the IQCARO-QoC Decalogue, was completed by IBD patients. We described patients’ assessment of QoC across Spanish patients. A univariable and multivariable analysis was performed to explore the associations between patients’ characteristics and QoC.

Results

Questionnaires from 788 participant patients were analysed. Participants’ mean age was 43.4 years, 63% were females and 58% had Crohn’s disease. The mean QoC score was 8.1 (± 2.4 SD) points out of a maximum of 10. Items with the lowest score were related to the provision of information and the implication of the medical team throughout the entire patient care. Factors associated with better QoC scores included: being employed better disease control, fewer numbers of unscheduled visits, and being followed by a gastroenterologist specialized in IBD.

Conclusions

Spanish patients’ reported QoC seems to be globally good although there is room for improvement, especially in providing adequate information to patients. Care provided by specialized IBD gastroenterologists seems to be related with higher QoC scores.

CRISPR-Cas9 Technology as a Tool to Target Gene Drivers in Cancer: Proof of Concept and New Opportunities to Treat Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a hematopoietic malignancy produced by a unique oncogenic event involving the constitutively active tyrosine-kinase (TK) BCR/ABL1. TK inhibitors (TKI) changed its prognosis and natural history. Unfortunately, ABL1 remains unaffected by TKIs. Leukemic stem cells (LSCs) remain, and resistant mutations arise during treatment. To address this problem, we have designed a therapeutic CRISPR-Cas9 deletion system targeting BCR/ABL1. The system was efficiently electroporated to cell lines, LSCs from a CML murine model, and LSCs from CML patients at diagnosis, generating a specific ABL1 null mutation at high efficiency and allowing the edited leukemic cells to be detected and tracked. The CRISPR-Cas9 deletion system triggered cell proliferation arrest and apoptosis in murine and human CML cell lines. Patient and murine-derived xenografts with CRISPR-edited LSCs in NOD SCID gamma niches revealed that normal multipotency and repopulation ability of CRISPR edited LSCs were fully restored. Normal hematopoiesis was restored, avoiding myeloid bias. To the best of our knowledge, we show for the first time how a CRISPR-Cas9 deletion system efficiently interrupts BCR/ABL1 oncogene in primary LSCs to bestow a therapeutic benefit. This study is a proof of concept for genome editing in all those diseases, like CML, sustained by a single oncogenic event, opening up new therapeutic opportunities.

Assessment of the association between cytomegalovirus DNAemia and subsequent acute graft-versus-host disease in allogeneic peripheral blood stem cell transplantation: A multicenter study from the Spanish hematopoietic transplantation and cell therapy group

The potential role of active CMV infection in promoting acute Graft-versus-Host Disease (aGvHD) in allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. We further addressed this issue conducting a retrospective, observational, multicenter study of 632 patients subjected to allogeneic peripheral blood HSCT at 20 Spanish centers. Monitoring of CMV DNA load in plasma or whole blood was performed by real-time PCR assays. Cumulative incidence of CMV DNAemia was 48.9% (95% CI, 45%-52.9%), of any grade aGvHD, 45.6; 95% (CI, 41.3%-50.1%), and of grade II-IV aGvHD, 30.7 (95% CI, 24.9%-36.4%). Overall, development of CMV DNAemia at any level resulted in an increased risk of subsequent all grade (HR, 1.38; 95% CI, 1.08 - 1.76; P = .009) or grade II-IV (HR, 1.58; 95% CI, 1.22 - 2.06; P = .001) aGvHD. The increased risk of aGvHD linked to prior occurrence of CMV DNAemia was similar to the above when only clinically significant episodes were considered for the analyses (HR for all grade aGvHD, 1.48; 95% CI, 1.13 - 1.91; P = .041, and HR for grade II-IV aGvHD, 1.53; 95% CI. 1.13-1.81; P = .04). The CMV DNA doubling time in blood was comparable overall in episodes of CMV DNAemia whether followed by aGvHD or not. Whether CMV replication is a surrogate risk marker of aGvHD or it is causally involved is an important question to be addressed in future experimental research.

Cytomegalovirus DNAemia and risk of mortality in allogeneic hematopoietic stem cell transplantation: Analysis from the Spanish Hematopoietic Transplantation and Cell Therapy Group

The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.

Risk factors and outcome of COVID-19 in patients with hematological malignancies

Background

Prognostic factors of poor outcome in patients with hematological malignancies and COVID-19 are poorly defined.

Patients and methods

This was a Spanish transplant group and cell therapy (GETH) multicenter retrospective observational study, which included a large cohort of blood cancer patients with laboratory-confirmed SARS-CoV-2 infection through PCR assays from March 1st 2020 to May 15th 2020.

Results

We included 367 pediatric and adult patients with hematological malignancies, including recipients of autologous (ASCT) (n = 58) or allogeneic stem cell transplantation (allo-SCT) (n = 65) from 41 hospitals in Spain. Median age of patients was 64 years (range 1–93.8). Recipients of ASCT and allo-SCT showed lower mortality rates (17% and 18%, respectively) compared to non-SCT patients (31%) (p = 0.02). Prognostic factors identified for day 45 overall mortality (OM) by logistic regression multivariate analysis included age > 70 years [odds ratio (OR) 2.1, 95% confidence interval (CI) 1.2–3.8, p = 0.011]; uncontrolled hematological malignancy (OR 2.9, 95% CI 1.6–5.2, p < 0.0001); ECOG 3–4 (OR, 2.56, 95% CI 1.4–4.7, p = 0.003); neutropenia (< 0.5 × 10⁹/L) (OR 2.8, 95% CI 1.3–6.1, p = 0.01); and a C-reactive protein (CRP) > 20 mg/dL (OR 3.3, 95% CI 1.7–6.4, p < 0.0001). In multivariate analysis of 216 patients with very severe COVID-19, treatment with azithromycin or low dose corticosteroids was associated with lower OM (OR 0.42, 95% CI 0.2–0.89 and OR 0.31, 95% CI 0.11–0.87, respectively, p = 0.02) whereas the use of hidroxycloroquine did not show significant improvement in OM (OR 0.64, 95% CI 0.37–1.1, P = 0.1).

Conclusions

In most patients with hematological malignancies COVID-19 mortality was directly driven by older age, disease status, performance status, as well as by immune (neutropenia) parameters and level of inflammation (high CRP). Use of azithromycin and low dose corticosteroids may be of value in very severe COVID-19.

Splice donor site sgRNAs enhance CRISPR/Cas9-mediated knockout efficiency

CRISPR/Cas9 allows the generation of knockout cell lines and null zygotes by inducing site-specific double-stranded breaks. In most cases the DSB is repaired by non-homologous end joining, resulting in small nucleotide insertions or deletions that can be used to construct knockout alleles. However, these mutations do not produce the desired null result in all cases, but instead generate a similar, functionally active protein. This effect could limit the therapeutic efficiency of gene therapy strategies based on abrogating oncogene expression, and therefore needs to be considered carefully. If there is an acceptable degree of efficiency of CRISPR/Cas9 delivery to cells, the key step for success lies in the effectiveness of a specific sgRNA at knocking out the oncogene, when only one sgRNA can be used. This study shows that the null effect could be increased with an sgRNA targeting the splice donor site (SDS) of the chosen exon. Following this strategy, the generation of null alleles would be facilitated in two independent ways: the probability of producing a frameshift mutation and the probability of interrupting the canonical mechanism of pre-mRNA splicing. In these contexts, we propose to improve the loss-of-function yield driving the CRISPR system at the SDS of critical exons.

To freeze or not to freeze peripheral blood stem cells prior to allogeneic transplantation from matched related donors

BACKGROUND

The standard practice in allogeneic stem cell transplant (alloSCT) is to infuse peripheral blood stem cells (PBSC) the same day or the day after collection once the patient has received conditioning regimen. To obtain and freeze PBSC prior to SCT would be desirable to get a better logistic and to confirm the quality of the product. Unfortunately, studies comparing both approaches are lacking.

AIM

In this retrospective study, we analyze the impact of using fresh (N: 107) or previously frozen PBSC (N: 224) on overall outcomes among patients consecutively undergoing alloPBSCT from a matched related donor.

RESULTS

Granulocyte engraftment (>500/mcl × 3 days) was faster in the frozen group (14 vs. 16 days, respectively; P = 0.001), while no significant differences on platelet recovery were observed. Patients receiving frozen PBSC had a higher incidence of global acute graft-versus-host disease (aGVHD) (63 vs. 44%, P < 0.001) mostly involving skin and had an earlier onset (13 vs. 30 days, P < 0.001). Response to first-line treatment with corticoids was similar in both groups. No statistically significant differences were found regarding overall chronic GVHD (58 vs. 66%) nor global survival (44 vs 48%), disease-free survival (39 vs. 33%), non-relapse mortality (24 vs. 16% at 1 year), and relapse rates in the frozen vs. fresh group, respectively.

CONCLUSIONS

Infusion of previously frozen stem cells may achieve similar overall outcomes compared to fresh infusion, allowing to program donor apheresis and transplantation. However, cryopreservation might influence on the different pattern of aGVHD, issue that deserves further studies.

First Report of Rust Caused by Phakopsora pachyrhizi on Soybean and Kudzu in Texas

The Asian soybean rust fungus, Phakopsora pachyrhizi H. Sydow & Sydow, was found on a 0.4-ha patch of kudzu (Pueraria lobata) near Dayton (Liberty County) in East Texas on November 2, 2005. Nearly 100% of the 300 leaflets examined were diseased with severity ranging from 5 to >100 lesions per leaflet. Eleven soybean fields as much as 20 km away were scouted and no infected plants were found. Asian soybean rust was also found on a 0.4-ha field of soybean (Glycine max cv. Vernal) on February 14, 2006 at the Texas A&M Agricultural Experiment Station in Weslaco (Hidalgo County) in the Lower Rio Grande Valley (LRGV) of Texas. Disease incidence was 100% (severity ranging from 5 to >100 lesions per leaflet) on 50 younger plants with green leaves along the edges of the field, whereas most of the plants in this field had senesced. These plants were not symptomatic and were at the R6 stage (full seed) when this field was previously scouted on December 19, 2005. Lesions on leaflets of kudzu and soybean were small and angular with erumpent uredinia typical of P. pachyrhizi. Urediniospores were ovoid or globose, hyaline, and measured 25 to 30 × 14 to 21 μm. Leaf samples with pustules were positive for P. pachyrhizi using enzyme-linked immunosorbent assay (ELISA) (Envirologix, Portland, ME). Morphological and polymerase chain reaction (PCR) identification of P. pachyrhizi from kudzu and soybean samples were confirmed by the USDA-APHIS-PPQ NIS and CPHST laboratories in Beltsville, MD as previously described (2). The kudzu in East Texas is not likely to support overwintering of the pathogen because it usually dies back during the winter. Leaves at this site were dead by January 17, 2006. This is the southernmost infestation of kudzu in Texas known to us. In contrast, the LRGV has a subtropical climate that would favor year-round survival of the fungus (3). This area, where 120 to 160 ha of soybeans are grown, may be a source of inoculum for soybean rust epidemics in the Midwest. Spore movement would follow the same pattern as seen with cereal rusts (1). However, soybeans are typically absent from the LRGV between late December and early March, so survival of the fungus during this interval would require other hosts. Regardless of whether the fungus overwinters here, or moves in from elsewhere, the LRGV spring crop could serve as an early indicator of a potential rust epidemic. References: (1) M. G. Eversmeyer and C. L. Kramer. Annu. Rev. Phytopathol. 38:491, 2000. (2) J. M. Mullen et al. Plant Dis. 90:112, 2006. (3) S. Pivonia et al. Plant Dis. 89:678, 2005.