Shifting from the treat-to-target to the early highly effective treatment approach in patients with multiple sclerosis - real-world evidence from Germany.

Background: While evidence highlights the effectiveness of initiating disease-modifying therapy with a high-efficacy medication for multiple sclerosis (MS) patients with poor prognostic factors, it remains unclear whether this approach has been adopted by a broad range of MS providers in Germany yet. Objective: To assess the adoption of the early highly effective treatment (EHT) compared to the treat-to-target treatment approach with the option of escalating treatment efficacy over time in Germany based on real-world evidence data. Design: Patient-level pharmacy dispensing data from the Permea platform were analysed from 2020 to 2022. Methods: In total, 29,529 therapy beginners (>18 years) were included to analyse shifts in treatment approaches over time and switching behaviour. Medication classification adhered to the German Society of Neurology guidelines and designated fumarates, glatiramer acetate, teriflunomide and interferons as low-efficacy category 1 medications; cladribine and S1P-modulators as medium-efficacy category 2 medications; and alemtuzumab, natalizumab, ocrelizumab, ofatumumab and rituximab (off-label) as high-efficacy category 3 medications. Results: Our results show that 70.0% of patients redeemed their first prescription for category 1 medication, 16.3% for category 2 and 13.7% for category 3 medications. The proportion of prescriptions filled shifted from 2020 to 2022 with a decrease of 14.7% for category 1 drugs and an increase of 12.5% for category 3 drugs. 93.2% of patients stayed on their initially prescribed medication category. 3.2% of category 1 and 3.7% of category 2 therapy beginners escalated to category 3 medication. 3.4% of category 3 medication users de-escalated their treatment to category 1 or category 2. Conclusion: While most individuals started their treatment according to the treat-to-target approach and remained on their initially prescribed medication category, there has been a steadily increasing shift towards the EHT approach since 2020. These insights demonstrate that, while not officially recommended by German guidelines, MS providers increasingly adopt the EHT approach.

Pathogen Resistance Depending on Jacalin-Dirigent Chimeric Proteins Is Common among Poaceae but Absent in the Dicot Arabidopsis as Evidenced by Analysis of Homologous Single-Domain Proteins.

MonocotJRLs are Poaceae-specific two-domain proteins that consist of a jacalin-related lectin (JRL) and a dirigent (DIR) domain which participate in multiple developmental processes, including disease resistance. For OsJAC1, a monocotJRL from rice, it has been confirmed that constitutive expression in transgenic rice or barley plants facilitates broad-spectrum disease resistance. In this process, both domains of OsJAC1 act cooperatively, as evidenced from experiments with artificially separated JRL- or DIR-domain-containing proteins. Interestingly, these chimeric proteins did not evolve in dicotyledonous plants. Instead, proteins with a single JRL domain, multiple JRL domains or JRL domains fused to domains other than DIR domains are present. In this study, we wanted to test if the cooperative function of JRL and DIR proteins leading to pathogen resistance was conserved in the dicotyledonous plant Arabidopsis thaliana. In Arabidopsis, we identified 50 JRL and 24 DIR proteins, respectively, from which seven single-domain JRL and two single-domain DIR candidates were selected. A single-cell transient gene expression assay in barley revealed that specific combinations of the Arabidopsis JRL and DIR candidates reduced the penetration success of barley powdery mildew. Strikingly, one of these pairs, AtJAX1 and AtDIR19, is encoded by genes located next to each other on chromosome one. However, when using natural variation and analyzing Arabidopsis ecotypes that express full-length or truncated versions of AtJAX1, the presence/absence of the full-length AtJAX1 protein could not be correlated with resistance to the powdery mildew fungus Golovinomyces orontii. Furthermore, an analysis of the additional JRL and DIR candidates in a bi-fluorescence complementation assay in Nicotiana benthamiana revealed no direct interaction of these JRL/DIR pairs. Since transgenic Arabidopsis plants expressing OsJAC1-GFP also did not show increased resistance to G. orontii, it was concluded that the resistance mediated by the synergistic activities of DIR and JRL proteins is specific for members of the Poaceae, at least regarding the resistance against powdery mildew. Arabidopsis lacks the essential components of the DIR-JRL-dependent resistance pathway.

Real-world use and acceptance of rituximab biosimilars in non-Hodgkin lymphoma in an oncologist network in Germany.

Aim: Present real-world data for rituximab (biosimilar and reference)-containing regimens in extrapolated indications in non-Hodgkin lymphoma (NHL)/chronic lymphocytic leukemia (CLL). Patients & methods: Data collected from office-based oncologic practices in Germany (July 2017-June 2019). Results: Of 1741 patients, 1241 had NHL; 500 had CLL. Of 7595 therapy cycles, 28.3% used reference rituximab; 55.2% used rituximab biosimilars; 2.0% used subcutaneous rituximab; 14.5% used rituximab, not otherwise specified. Rituximab biosimilars were used across all indications; 57.3% of cycles were administered in extrapolated indications. Over 24 months, the proportion of rituximab prescriptions that were for biosimilars increased from 12.0 to 83.0%. Conclusion: Our real-world data in NHL and CLL depicts increasing use of rituximab biosimilars across multiple treatment protocols, including extrapolated indications.

Leukemia surfaceome analysis reveals new disease-associated features.

A better description of the leukemia cell surface proteome (surfaceome) is a prerequisite for the development of diagnostic and therapeutic tools. Insights into the complexity of the surfaceome have been limited by the lack of suitable methodologies. We combined a leukemia xenograft model with the discovery-driven chemoproteomic Cell Surface Capture technology to explore the B-cell precursor acute lymphoblastic leukemia (BCP-ALL) surfaceome; 713 cell surface proteins, including 181 CD proteins, were detected through combined analysis of 19 BCP-ALL cases. Diagnostic immunophenotypes were recapitulated in each case, and subtype specific markers were detected. To identify new leukemia-associated markers, we filtered the surfaceome data set against gene expression information from sorted, normal hematopoietic cells. Nine candidate markers (CD18, CD63, CD31, CD97, CD102, CD157, CD217, CD305, and CD317) were validated by flow cytometry in patient samples at diagnosis and during chemotherapy. CD97, CD157, CD63, and CD305 accounted for the most informative differences between normal and malignant cells. The ALL surfaceome constitutes a valuable resource to assist the functional exploration of surface markers in normal and malignant lymphopoiesis. This unbiased approach will also contribute to the development of strategies that rely on complex information for multidimensional flow cytometry data analysis to improve its diagnostic applications.

Xenografts of highly resistant leukemia recapitulate the clonal composition of the leukemogenic compartment.

Clonal evolution of the leukemogenic compartment may contribute to alter the therapeutic response in acute lymphoblastic leukemia (ALL). Using xenotransplantation of primary leukemia cells, we evaluated the phenotypic and genetic composition of de novo resistant very high risk precursor B-cell ALL, a subgroup defined by the persistence of minimal residual disease despite intensive chemotherapy. Analysis of copy number alterations (CNAs) showed that the xenografted leukemia, even when reconstituted from 100 cells, remained highly related to the diagnostic sample, with minor changes in CNAs, mostly deletions, emerging in most cases in the first passage into mice. At the single-cell level, the pattern of monoallelic and biallelic deletions of the CDKN2A locus revealed distinct leukemia subpopulations, which were reproducibly tracked in xenografts. In most very high risk ALL cases, the predominant diagnostic clones were reconstituted in xenografts, as shown by multiplex polymerase chain reaction analysis of immunoglobulin and T-cell receptor loci. In other cases, the pattern in CNAs and immunoglobulin and T-cell receptor rearrangement was less concordant in xenografts, suggesting the outgrowth of subclones. These results unequivocally demonstrate the existence of clonally closely related but distinct subsets of leukemia initiating cells in ALL, which has important implications for drug development and preclinical disease modeling.

Ex vivo supplementation with nicotinic acid enhances cellular poly(ADP-ribosyl)ation and improves cell viability in human peripheral blood mononuclear cells.

Poly(ADP-ribosyl)ation is a posttranslational modification of proteins, which is mainly catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1) by using NAD(+) as substrate and is directly triggered by DNA strand breaks. Under mild genotoxic stress poly(ADP-ribose) (PAR) formation plays an important role in DNA repair whereas severe genotoxic stress and the ensuing overactivation of PARP-1 induce cellular NAD(+) depletion, energy failure and ultimately cell death. We are interested in studying the consequences of moderately enhanced enzymatic activity under conditions of DNA damage. Here we chose supplementation of cells with the NAD(+) precursor nicotinic acid (NA) as a strategy. In order to reliably assess PAR accumulation in living cells we first developed a novel, sensitive flow-cytometric method for the rapid analysis of poly(ADP-ribose) accumulation (RAPARA). Our data showed that ex vivo supplementation of human peripheral blood mononuclear cells (PBMC) with low concentrations of NA significantly raised cellular NAD(+) levels by 2.1-fold. Upon X-irradiation or exposure to hydrogen peroxide or N-methyl-N'-nitro-N-nitrosoguanidine, PAR accumulation was significantly increased and sustained in NA-supplemented cells. Furthermore, NA-supplemented PBMC displayed significantly higher cell viability due to a lower rate of necrotic cell death. In summary, ex vivo supplementation of human PBMC with NA increases cellular NAD(+) levels, boosts the cellular poly(ADP-ribosyl)ation response to genotoxic treatment, and protects from DNA-damage-induced cell death.

Induction of autophagy-dependent necroptosis is required for childhood acute lymphoblastic leukemia cells to overcome glucocorticoid resistance.

In vivo resistance to first-line chemotherapy, including to glucocorticoids, is a strong predictor of poor outcome in children with acute lymphoblastic leukemia (ALL). Modulation of cell death regulators represents an attractive strategy for subverting such drug resistance. Here we report complete resensitization of multidrug-resistant childhood ALL cells to glucocorticoids and other cytotoxic agents with subcytotoxic concentrations of obatoclax, a putative antagonist of BCL-2 family members. The reversal of glucocorticoid resistance occurred through rapid activation of autophagy-dependent necroptosis, which bypassed the block in mitochondrial apoptosis. This effect was associated with dissociation of the autophagy inducer beclin-1 from the antiapoptotic BCL-2 family member myeloid cell leukemia sequence 1 (MCL-1) and with a marked decrease in mammalian target of rapamycin (mTOR) activity. Consistent with a protective role for mTOR in glucocorticoid resistance in childhood ALL, combination of rapamycin with the glucocorticoid dexamethasone triggered autophagy-dependent cell death, with characteristic features of necroptosis. Execution of cell death, but not induction of autophagy, was strictly dependent on expression of receptor-interacting protein (RIP-1) kinase and cylindromatosis (turban tumor syndrome) (CYLD), two key regulators of necroptosis. Accordingly, both inhibition of RIP-1 and interference with CYLD restored glucocorticoid resistance completely. Together with evidence for a chemosensitizing activity of obatoclax in vivo, our data provide a compelling rationale for clinical translation of this pharmacological approach into treatments for patients with refractory ALL.

Down syndrome acute lymphoblastic leukemia, a highly heterogeneous disease in which aberrant expression of CRLF2 is associated with mutated JAK2: a report from the International BFM Study Group.

We report gene expression and other analyses to elucidate the molecular characteristics of acute lymphoblastic leukemia (ALL) in children with Down syndrome (DS). We find that by gene expression DS-ALL is a highly heterogeneous disease not definable as a unique entity. Nevertheless, 62% (33/53) of the DS-ALL samples analyzed were characterized by high expression of the type I cytokine receptor CRLF2 caused by either immunoglobulin heavy locus (IgH@) translocations or by interstitial deletions creating chimeric transcripts P2RY8-CRLF2. In 3 of these 33 patients, a novel activating somatic mutation, F232C in CRLF2, was identified. Consistent with our previous research, mutations in R683 of JAK2 were identified in 10 specimens (19% of the patients) and, interestingly, all 10 had high CRLF2 expression. Cytokine receptor-like factor 2 (CRLF2) and mutated Janus kinase 2 (Jak2) cooperated in conferring cytokine-independent growth to BaF3 pro-B cells. Intriguingly, the gene expression signature of DS-ALL is enriched with DNA damage and BCL6 responsive genes, suggesting the possibility of B-cell lymphocytic genomic instability. Thus, DS confers increased risk for genetically highly diverse ALLs with frequent overexpression of CRLF2, associated with activating mutations in the receptor itself or in JAK2. Our data also suggest that the majority of DS children with ALL may benefit from therapy blocking the CRLF2/JAK2 pathways.