ADAMTS13 recovery in acute thrombotic thrombocytopenic purpura after caplacizumab therapy.

ABSTRACT: Caplacizumab prevents the interaction between von Willebrand factor and platelets and is used to treat immune thrombotic thrombocytopenic purpura (iTTP). Its administration has been associated with a delay in ADAMTS13 activity restoration after plasma exchange (PEX) suspension. We analyzed the outcomes of 113 iTTP episodes, 75 of which were treated with caplacizumab, in 108 patients from the Spanish Registry of Thrombotic Thrombocytopenic Purpura. Caplacizumab shortened the time to platelet count normalization and reduced PEX requirement, exacerbations, and relapses. There was no difference in the time to achieve ADAMTS13 activity ≥20% after PEX end between caplacizumab-treated and nontreated episodes (median [interquartile range], 14.5 [7.7-27.2] vs 13.0 [8.0-29.0] days, P = .653). However, considering the 36 episodes in which caplacizumab was started ≤3 days after iTTP diagnosis, the time for ADAMTS13 restoration from PEX end was higher than in those episodes in which caplacizumab was started >3 days after iTTP diagnosis (20.0 [12.0-43.0] vs 11.0 [3.5-20.0] days, P = .003) or than in non-caplacizumab-treated episodes (P = .033). This finding could be related to a significantly shorter duration of PEX in early caplacizumab-treated episodes than in late caplacizumab-treated episodes (5.5 [4.0-9.0] vs 15.0 [11.0-21.5] days, P < .001) or non-caplacizumab-treated episodes (11.0 [6.0-26.0] days, P < .001). There were no differences in time to ADAMTS-13 restoration from PEX start (28.0 [17.2-47.5], 27.0 [19.0-37.5] and 29.5 [15.2-45.0] days in early caplacizumab-treated, late caplacizumab-treated and non-caplacizumab-treated episodes). Early administered caplacizumab does not prevent the requirement for immunosuppression but has beneficial effects by shortening PEX requirement without major safety concerns.

[Immunotherapy in multiple myeloma]. / Inmunoterapia en el mieloma múltiple.

Patients with multiple myeloma who present with refractory disease or relapse after receiving the main classes of available drugs -immunomodulators, proteasome inhibitors and antibodies against CD38- do not have satisfactory therapeutic alternatives. New treatments based on the redirection of T lymphocytes to act directly against tumor cells, such as bispecific antibodies and T cells with chimeric antigen receptors, are changing this scenario. The published information confirms unprecedented antitumor activity of these agents in patients with refractory myeloma and they will certainly represent the backbone of the treatment of these patients in the immediate future. However, these therapies also present specific characteristics and medium or long-term toxicities that pose new healthcare challenges. In this review, we address the current results and future challenges of the administration of these treatments in patients with relapsed or refractory multiple myeloma.

Real-World Experience in Extracorporeal Photopheresis for Adults with Graft-versus-Host Disease.

Extracorporeal photopheresis (ECP) has shown efficacy in treating graft-versus-host disease (GVHD). We aim to summarize eight years of real-world experience with off-line ECP in our institution, in order to validate this treatment schedule and analyze predictive factors. All consecutive adult patients with steroid-dependent or steroid-refractory GVHD undergoing off-line ECP were included in this single-center retrospective study. ECP was performed with a Spectra Optia device, processing 1 total blood volume, at a twice-weekly frequency for acute GVHD (aGVHD) and once weekly for chronic GVHD (cGVHD), and tapered individually according to clinical response. The cumulative incidence of response, including complete response (CR) and partial response (PR), were compared among patients grouped by different baseline, apheresis, and disease characteristics. Between January 2015 and May 2022, a total of 1382 ECP procedures were proposed for 82 patients. No incidents were reported in 97% of the ECP sessions. GVHD responded in 78% of patients (aGVHD: 57% CR and 4% PR; cGVHD, 39% CR and 48% PR). Overall survival was statistically greater for aGVHD patients who responded to ECP compared to those who did not respond (67.5% versus 26% at 1 year; P = 0.037). Severity was an independent predictor of response in aGVHD, whereas the absence of mouth involvement and lower lymphocyte counts in the apheresis product correlated with a higher response in cGVHD. Our findings support the effectiveness of this treatment schedule for GVHD. Further investigation is required to identify ECP-specific predictive factors, given that findings are not homogeneous across studies.

Extracorporeal Photopheresis in Graft-versus-Host Disease.

Graft-versus-host disease (GVHD) is a major cause of mortality and morbidity following allogeneic hematopoietic stem cell transplantation. Extracorporeal photopheresis (ECP), which exposes mononuclear cells to ultraviolet A irradiation in the presence of a photosensitizing agent, has shown efficacy in the treatment of GVHD. Recent observations in molecular and cell biology have revealed the mechanisms by which ECP can reverse GVHD, including lymphocyte apoptosis, differentiation of dendritic cells from circulating monocytes, and modification of the cytokine profile and T cell subpopulations. Technical innovations have made ECP accessible to a broader range of patients; however, logistical constraints may limit its use. In this review, we scrutinize the development of ECP from its origins to recent insights into the biology underlying ECP efficacy. We also review practical aspects that may complicate successful ECP treatment. Finally, we analyze how these theoretical concepts translate into clinical practice, summarizing the published experiences of leading research groups worldwide.

Immune thrombotic thrombocytopenic purpura: clinical suspicion and basic management in emergency departments - an expert review and consensus statement from the Spanish societies of hematology and hemotherapy (SEHH) and emergency medicine (SEMES). / Púrpura trombocitopénica trombótica inmune: sospecha y manejo básico en los servicios de urgencias. Revisión y consenso de un grupo de expertos de las sociedades científicas SEHH y SEMES.

TEXT: Acquired or immune thrombotic thrombocytopenic purpura (TTP) are thrombotic microangiopathies associated with high mortality if treatment is not started early. Onset is usually sudden, meaning that the condition is often diagnosed in hospital emergency departments, where TTP must be suspected as early as possible. These guidelines were drafted by specialists in emergency medicine and hematology to cover the diagnosis, referral, and treatment of patients suspected of immune-mediated TTP who require emergency care. Immune TTP should be suspected whenever a patient presents with hemolytic microangiopathy and has a negative Coombs test, and thrombocytopenia, possibly in conjunction with fever and neurologic and cardiac alterations. If one of the existing diagnostic algorithms indicates there is a high probability that the patient has immune TTP, plasma exchange therapy should be started along with immunosuppressants. Treatment with caplacizumab should also be considered. The patient should be referred immediately to the hematology department within the same hospital or a referral hospital.

TEXTO: La púrpura trombótica trombocitopénica adquirida o inmune (PTTi) es una microangiopatía trombótica (MAT) con una elevada mortalidad si no se instaura un tratamiento precoz. El inicio habitualmente brusco de la enfermedad hace que, en la mayoría de los pacientes, el diagnóstico inicial se haga en los servicios de urgencias hospitalarios (SUH), donde se debe sospechar esta entidad con la mayor inmediatez posible. Esta guía, elaborada por profesionales de Medicina de Urgencias y de Hematología, establece unas recomendaciones en cuanto al diagnóstico, derivación y tratamiento de los pacientes con sospecha de PTTi en los SUH. Se debe sospechar PTTi en todo paciente que presente una anemia hemolítica microangiopática, prueba de Coombs directo negativa y trombocitopenia pudiendo asociar, además, fiebre, alteraciones neurológicas y cardiacas. Si tras la aplicación de alguno de los algoritmos diagnósticos existentes, hay una alta probabilidad de que el paciente presente una PTTi, debería iniciarse tratamiento con recambio plasmático, inmunosupresores y valorar el inicio de caplacizumab. Además, debe gestionarse el traslado inmediato de los pacientes al Servicio de Hematología, bien del mismo centro o a uno de referencia.

An update on the pathogenesis and diagnosis of thrombotic thrombocytopenic purpura.

INTRODUCTION: Severe ADAMTS13 deficiency defines thrombotic thrombocytopenic purpura (TTP). ADAMTS13 is responsible for VWF cleavage. In the absence of this enzyme, widespread thrombi formation occurs, causing microangiopathic anemia and thrombocytopenia and leading to ischemic organ injury. Understanding ADAMTS13 function is crucial to diagnose and manage TTP, both in the immune and hereditary forms. AREAS COVERED: The role of ADAMTS13 in coagulation homeostasis and the consequences of its deficiency are detailed. Other factors that modulate the consequences of ADAMTS13 deficiency are explained, such as complement system activation, genetic predisposition, or the presence of an inflammatory status. Clinical suspicion of TTP is crucial to start prompt treatment and avoid mortality and sequelae. Available techniques to diagnose this deficiency and detect autoantibodies or gene mutations are presented, as they have become faster and more available in recent years. EXPERT OPINION: A better knowledge of TTP pathophysiology is leading to an improvement in diagnosis and follow-up, as well as a customized treatment in patients with TTP. This scenario is necessary to define the role of new targeted therapies already available or coming soon and the need to better diagnose and monitor at the molecular level the evolution of the disease.

Role of extracorporeal photopheresis in the management of children with graft-vs-host disease.

INTRODUCTION: Graft-vs-host disease (GVHD) is a frequent cause of morbidity and mortality in allogeneic stem cell transplants. Extracorporeal photopheresis (ECP) is one of the most accepted second-line treatments, but technical issues of ECP in children might be prohibitive. MATERIALS AND METHODS: Patients under 18 y of age with corticodependant or corticorefractory GVHD receiving ECP at our hospital were included in this retrospective study. ECP was performed with an in-line system (CellExTherakos) in 2013-2014 and with an off-line system (Spectra Optia) from 2015 onwards. Cumulative incidence curves were obtained to compare ECP efficacy among patients grouped by different baseline, apheresis, and disease characteristics. Significant variables on univariate analysis (Gray's test) were pooled into a multivariate analysis (Fine-Gray proportional hazard regression for competing events). RESULTS: A total of 701 ECP sessions were performed on 33 patients between October 2013 and December 2021. In total, 97% of the sessions could be executed. In 8% of the sessions an incident was detected, most of them mild and related to catheter dysfunction. With a median follow-up for alive patients of 33.6 mo (range, 8-95), the composite partial and complete response cumulative incidence was 70% (95% confidence interval, 51%-82%) and the median time to maximal response was 2.8 mo (range, 0.25-9.8). Significantly lower response ratios were found in patients with hepatic, gastrointestinal, acute, or severe GVHD. The only variable that influenced response on multivariate analysis was GVHD severity. DISCUSSION: ECP is feasible, safe, and effective for pediatric patients with corticorefractory or corticodependant GVHD, offering a less toxic and nonimmunosuppressive treatment option.

How to Manage Patients with Lenalidomide-Refractory Multiple Myeloma.

Although lenalidomide-based combinations, such as lenalidomide plus a proteasome inhibitor or an anti-CD38 monoclonal antibody, improve the overall response rate, progression-free survival, and overall survival of patients with relapsed/refractory multiple myeloma (RRMM), there is a tendency to use these regimens as a frontline treatment. This strategy has led to the development of refractoriness early in the disease course, usually after the patient's first treatment. Since lenalidomide-free regimens have so far shown limited efficacy in lenalidomide-refractory patients, there is an unmet need for other treatment options. In this review, we discuss the therapeutic options available to treat the general population of lenalidomide-refractory patients (mono, double and triple refractory) and the subpopulation of patients with other high-risk features such as renal failure, extramedullary disease, and high-risk cytogenetics. Moreover, new promising individual therapies and the possible impact of immunotherapy in RRMM patients are debated.

Best practices and recommendations for drug regimens and plasma exchange for immune thrombotic thrombocytopenic purpura.

INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ injury. TTP pathophysiology is based on a severe ADAMTS13 deficiency, and is a medical emergency with fatal outcome if appropriate treatment is not initiated promptly. AREAS COVERED: Authors will review the best options currently available to minimize mortality, prevent relapses, and obtain the best clinical response in patients with immune TTP (iTTP). Available bibliography about iTTP treatment has been searched in Library's MEDLINE/PubMed database from January 1990 until April 2021. EXPERT OPINION: The generalized use of plasma exchange marked a paradigm in the management of iTTP. In recent years, strenuous efforts have been done for a better understanding of the pathophysiology of this disease, improve diagnosis, optimize treatment, reduce mortality, and prevent recurrences. The administration of front-line rituximab and, more recently, the availability of caplacizumab, the first targeted therapy for iTTP, have been steps toward a further reduction in early mortality and for the prevention of relapses.