Drugs Targeting CD20 in Multiple Sclerosis: Pharmacology, Efficacy, Safety, and Tolerability.

Currently, there are four monoclonal antibodies (mAbs) that target the cluster of differentiation (CD) 20 receptor available to treat multiple sclerosis (MS): rituximab, ocrelizumab, ofatumumab, and ublituximab. B-cell depletion therapy has changed the therapeutic landscape of MS through robust efficacy on clinical manifestations and MRI lesion activity, and the currently available anti-CD20 mAb therapies for use in MS are a cornerstone of highly effective disease-modifying treatment. Ocrelizumab is currently the only therapy with regulatory approval for primary progressive MS. There are currently few data regarding the relative efficacy of these therapies, though several clinical trials are ongoing. Safety concerns applicable to this class of therapeutics relate primarily to immunogenicity and mechanism of action, and include infusion-related or injection-related reactions, development of hypogammaglobulinemia (leading to increased infection and malignancy risk), and decreased vaccine response. Exploration of alternative dose/dosing schedules might be an effective strategy for mitigating these risks. Future development of biosimilar medications might make these therapies more readily available. Although anti-CD20 mAb therapies have led to significant improvements in disease outcomes, CNS-penetrant therapies are still needed to more effectively address the compartmentalized inflammation thought to play an important role in disability progression.

Vaccine-derived yellow fever in an immunocompromised patient on anti-CD20-antibody therapy and its treatment with sofosbuvir.

Yellow fever (YF) is a potentially lethal viral hemorrhagic fever that can be prevented with the 17D live attenuated YF vaccine. However, this vaccination can cause severe adverse reactions including vaccine-associated YF. Here, we describe the case of a 32-year-old female who was permanently immunosuppressed with an anti-CD20 antibody due to multiple sclerosis. Following YF vaccination, the patient developed a variety of symptoms such as febrile temperatures, muscle and joint pain, headaches, and dysuria. A vaccine-associated YF with viremia was diagnosed. To avoid a potentially severe course of the disease, sofosbuvir was used as antiviral treatment followed by the resolution of symptoms and serological response. As travelers with chronic diseases and immunosuppression will increasingly engage in long distance travel, this case demonstrates the importance of assessing patient history prior to the administration of live vaccines and points towards a possible therapeutic approach in those suffering from vaccine-associated YF.

Measurement of Trogocytosis: Quantitative Analyses Validated with Rigorous Controls.

Trogocytosis is a process in which receptors on acceptor cells remove and internalize cognate ligands from donor cells. Trogocytosis has a profound and negative impact on mAb-based cancer immunotherapy, as seen in the treatment of chronic lymphocytic leukemia (CLL) with CD20 mAbs, such as rituximab (RTX) and ofatumumab (OFA). Our clinical observations of RTX/OFA-mediated loss of the CD20 target from circulating CLL cells have been replicated in our in vitro studies. Here we describe flow cytometry and fluorescence microscopy experiments, which demonstrate that acceptor cells, such as monocytes/macrophages that express FcγR, remove and internalize both antigen and donor cell-bound cognate IgG mAbs for several different mAb-donor cell pairs. Fluorescent mAbs and portions of the plasma cell membrane are transferred from donor cells to acceptor cells, which include the THP-1 monocytic cell line as well as freshly isolated monocytes. We describe rigorous controls to validate the reactions and eliminate dissociation or internalization as alternative mechanisms. Trogocytosis is likely to contribute to neutropenia, thrombocytopenia, and liver damage associated with use of antibody-drug conjugates. The methods we have described should allow for examination of strategies focused on blocking trogocytosis and its adverse effects. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Trogocytosis of mAb-opsonized donor cells mediated by adherent THP-1 cells Alternate Protocol: Application of fluorescence microscopy to examine THP-1 cell-mediated trogocytosis Support Protocol 1: Alexa labeling of mAbs and determination of F/P ratios Support Protocol 2: Standard washing procedure Support Protocol 3: Labeling and opsonization of cells Basic Protocol 2: Trogocytosis mediated by human monocytes as acceptor cells Support Protocol 4: Isolation of human monocytes Basic Protocol 3: Trogocytosis mediated by THP-1 cells in solution Support Protocol 5: Retinoic acid treatment of THP-1 cells Support Protocol 6: Culturing of SCC-25, BT-474, MOLT-4 and THP-1 cell lines.

Anti-CD20 therapies in pregnancy and breast feeding: a review and ABN guidelines.

Neurologists increasingly use anti-CD20 therapies, including for women of childbearing age, despite these medications being unlicensed for use in pregnancy. Current evidence suggests that women can safely conceive while taking anti-CD20 therapy. Women should not be denied treatment during pregnancy when it is clinically indicated, although they should be counselled regarding live vaccinations for their infant. Women receiving regular ocrelizumab for multiple sclerosis should preferably wait 3 months before trying to conceive. There are few data around ofatumumab in pregnancy, and while there is probably a class effect across all anti-CD20 therapies, ofatumumab may need to be continued during pregnancy to maintain efficacy. We recommend that anti-CD20 therapies can be safely given while breast feeding. It is important to make time to discuss treatments with women of childbearing age to help them choose their most suitable treatment. Outcomes should be monitored in pregnancy registries.

CD20+ T cells: an emerging T cell subset in human pathology.

INTRODUCTION: Although CD20 is classically a B cell marker, in the last three decades, dim expression has been noted on a subset of T cells as well that has been independently verified by a number of groups. Our understanding of these cells and their function is not well established. METHODS: A thorough review of original articles on CD20+ T cells was undertaken of Pubmed by using combination of phrases including "CD20+", "CD20-positive" and "T cells". Articles in English were considered, and there was no time restriction. RESULTS: CD20+ T cells express the standard T cell markers and, in comparison to CD20¯ T cells, appear to express greater inflammatory cytokines and markers of effector function. Although the ontogeny of these cells is still being established, the current theory is that CD20 may be acquired by trogocytosis from B cells. CD20+ T cells may be found in healthy controls and in a wide range of pathologies including autoimmune diseases, haematological and non-haematological malignancies and human immunodeficiency virus (HIV) infections. One of the best studied diseases where these cells are found is multiple sclerosis (MS) where a number of therapeutic interventions, including anti-CD20 depletion, have been shown to effectively deplete these cells. CONCLUSION: This review summarises the latest understanding of CD20+ T cells, their presence in various diseases, their putative function and how they may be an ongoing target of CD20-depleting agents. Unfortunately, our understanding of these cells is still at its infancy and ongoing study in a wider range of pathologies is required.

[Hypogammaglobulinemia and Multiple Sclerosis - An Overlooked Correlation?] / Hypogammaglobulinämie und Multiple Sklerose.

Hypogammaglobulinemia and Multiple Sclerosis - An Overlooked Correlation? Abstract. Hypogammaglobulinemias occur in people with multiple sclerosis (MS) without immunotherapy in 8.1% of patients and with immunotherapy (not drug-specific) in up to 26.4% of affected individuals. This is thus significantly higher than the expected incidence in the general population. In MS patients it is also relevant to differentiate between primary and secondary hypogammaglobulinemia. In particular, anti-CD20 therapies are mainly underlying for the secondary forms in MS patients. With this article, we aim to provide a "spotlight" on hypogammaglobulinemia with a focus on the clinical consequence of these phenomena in people with MS.

An overview of pivotal trials and real-world evidence for CD20-depleting therapy in multiple sclerosis : Immunotherapy with rituximab, ocrelizumab, and ofatumumab.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system leading to demyelination and neurodegeneration of brain tissue. For a long time, research focused on T cells as the primary mechanism of disease. Driven by reports on the clinical results of B cell-depleting therapies, this therapeutic approach has come into focus in the last decade, and new highly effective treatments have been developed and are now complementing the therapeutic landscape. This review provides an overview of the development of B cell-depleting therapies and shows the advantages and disadvantages of current developments. In addition, we discuss basic considerations for CD20-depleted MS patients in the face of the COVID-19 pandemic.

Linfomas no Hodgkin indolentes y terapia anti-CD20: una revisión de la literatura / Indolent non-Hodgkin's lymphomas and anti-CD20 therapy: a literature review

Introducción: Los linfomas no Hodgkin indolentes se destacan por el reto que suponen desde el punto de vista terapéutico. La introducción de la terapia con rituximab, un anticuerpo monoclonal que se une al antígeno CD20 de la membrana de los linfocitos B, revolucionó los tratamientos hasta ese momento y abrió el camino para el desarrollo de otros anticuerpos monoclonales anti-CD20. Objetivo: Describir las características generales de los linfomas no Hodgkin indolentes y de los anticuerpos monoclonales anti-CD20, así como el rol de la terapia anti-CD20 en dichas enfermedades. Métodos: Se realizó una revisión de la literatura publicada en los últimos 20 años, disponible en los repositorios: Scielo, Scopus, Pubmed/Medline, ScienceDirect y Mediagraphic. Se emplearon para elaborar este manuscrito 35 documentos, de ellos 80 por ciento correspondieron a los últimos 5 años. Conclusiones: La sólida evidencia científica, acumulada durante las últimas dos décadas, respalda el uso clínico de los anticuerpos monoclonales anti-CD20 en el tratamiento de los linfomas no Hodgkin indolentes. El uso efectivo de estos fármacos como agentes únicos o combinados con quimioterapia demuestran su versatilidad terapéutica(AU)

Introduction: Indolent non-Hodgkin's lymphomas are notable for the challenge they pose from a therapeutic point of view. The introduction of rituximab, a monoclonal antibody that binds to the CD20 antigen of the B-lymphocyte membrane, revolutionized treatments up to that time and opened the way for the development of other anti-CD20 monoclonal antibodies. Objective: To describe the general characteristics of indolent non-Hodgkin's lymphomas and anti-CD20 monoclonal antibodies, as well as the role of anti-CD20 therapy in these diseases. Methods: A review of the literature published in the last 20 years, available in the repositories: Scielo, Scopus, Pubmed/Medline, Science Direct and Mediagraphic, was performed. Thirty-five papers were used to prepare this manuscript, 80 percent of which corresponded to the last 5 years. Conclusions: Strong scientific evidence, accumulated over the last two decades, supports the clinical use of anti-CD20 monoclonal antibodies in the treatment of indolent non-Hodgkin's lymphomas. The effective use of these drugs as single agents or in combination with chemotherapy demonstrates their therapeutic versatility(AU)

Bispecific targeting of CD20 and CD19 increases polyfunctionality of chimeric antigen receptor T-cell products in B-cell malignancies.

BACKGROUND AIMS: Selective immune pressure contributes to relapse due to target antigen downregulation in patients treated with anti-CD19 chimeric antigen receptor (CAR) T cells. Bispecific lentiviral anti-CD20/anti-CD19 (LV20.19) CAR T cells may prevent progression/relapse due to antigen escape. Highly polyfunctional T cells within a CAR T-cell product have been associated with response in single-antigen-targeted anti-CD19 CAR T cells. METHODS: The authors performed a single-cell proteomic analysis to assess polyfunctional cells in our LV20.19 CAR T-cell product. Analysis was limited to those treated at a fixed dose of 2.5 × 106 cells/kg (n = 16). Unused pre-infusion CAR T cells were thawed, sorted into CD4/CD8 subsets and stimulated with K562 cells transduced to express CD19 or CD20. Single-cell production of 32 individual analytes was measured and polyfunctionality and polyfunctional strength index (PSI) were calculated. RESULTS: Fifteen patients had adequate leftover cells for analysis upon stimulation with CD19, and nine patients had adequate leftover cells for analysis upon stimulation with CD20. For LV20.19 CAR T cells, PSI was 866-1109 and polyfunctionality was 40-45%, which were higher than previously reported values for other CAR T-cell products. CONCLUSIONS: Stimulation with either CD19 or CD20 antigens resulted in similar levels of analyte activation, suggesting that this product may have efficacy in CD19- patient populations.

Proinflammatory CD20+ T cells contribute to CNS-directed autoimmunity.

The origin and function of CD20+ T cells are poorly understood. Here, we characterized CD20+ T cells in mice and humans and investigated how they are affected by anti-CD20 antibody treatment. We report that murine CD20+ T cells are unable to endogenously express the B cell lineage marker CD20; the development of CD20+ T cells in rodents requires the presence of CD20-expressing B cells. Our results demonstrated that both murine and human T cells acquire CD20 from B cells via trogocytosis while being activated by an antigen-presenting B cell. In patients with multiple sclerosis (MS) and mice with experimental autoimmune encephalomyelitis (EAE), expression of CD20 on T cells is associated with an up-regulation of activation markers, proinflammatory cytokines, and adhesion molecules, suggesting high pathogenic potential. Supporting this hypothesis, CD20+ T cells expand during active EAE in rodents; furthermore, adoptive transfer of CD20+ T cells into EAE-diseased mice worsened histological and clinical severity. Of direct therapeutic relevance, we demonstrate that the exclusive therapeutic elimination of CD20+ T cells effectively ameliorates EAE, independent of B cells. The results support the hypothesis that CD20+ T cells arise upon B cell-T cell interaction and that depletion of CD20+ T cells might contribute to the success of anti-CD20 antibody therapies in MS and other inflammatory disorders.

Dosimetric Approaches for Radioimmunotherapy of Non-Hodgkin Lymphoma in Myeloablative Setting.

Radioimmunotherapy (RIT) is a safe and active treatment available for non-Hodgkin lymphomas (NHLs). In particular, two monoclonal antibodies raised against CD20, that is Zevalin (90Y-ibritumomab-tiuxetan) and Bexxar (131I-tositumomab) received FDA approval for the treatment of relapsing/refractory indolent or transformed NHLs. RIT is likely the most effective and least toxic anticancer agent in NHLs. However, its use in the clinical setting is still debated and, in case of relapse after optimized rituximab-containing regimens, the efficacy of RIT at standard dosage is suboptimal. Thus, clinical trials were based on the hypothesis that the inclusion of RIT in myeloablative conditioning would allow to obtain improved efficacy and toxicity profiles when compared to myeloablative total-body irradiation and/or high-dose chemotherapy regimens. Standard-activity RIT has a safe toxicity profile, and the utility of pretherapeutic dosimetry in this setting can be disputed. In contrast, dose-escalation clinical protocols require the assessment of radiopharmaceutical biodistribution and dosimetry before the therapeutic injection, as dose constrains for critical organs may be exceeded when RIT is administered at high activities. The aim of the present study was to review and discuss the internal dosimetry protocols that were adopted for non-standard RIT administration in the myeloablative setting before hematopoietic stem cell transplantation in patients with NHLs.

Pharmacodynamics and molecular correlates of response to glofitamab in relapsed/refractory non-Hodgkin lymphoma.

Glofitamab, a novel CD20xCD3, T-cell-engaging bispecific antibody, exhibited single-agent activity in Study NP30179, a first-in-human, phase 1 trial in relapsed/refractory B-cell non-Hodgkin lymphoma. Preclinical studies showed that glofitamab leads to T-cell activation, proliferation, and tumor cell killing upon binding to CD20 on malignant cells. Here, we provide evidence of glofitamab's clinical activity, including pharmacodynamic profile, mode of action, and factors associated with clinical response, by evaluating biomarkers in patient samples from the dose-escalation part of this trial. Patients enrolled in Study NP30179 received single-dose obinutuzumab pretreatment (1000 mg) 7 days before IV glofitamab (5 µg-25 mg). Glofitamab treatment lasted ≤12 cycles once every 2 or 3 weeks. Blood samples were collected at predefined time points per the clinical protocol; T-cell populations were evaluated centrally by flow cytometry, and cytokine profiles were analyzed. Immunohistochemical and genomic biomarker analyses were performed on tumor biopsy samples. Pharmacodynamic modulation was observed with glofitamab treatment, including dose-dependent induction of cytokines, and T-cell margination, proliferation, and activation in peripheral blood. Gene expression analysis of pretreatment tumor biopsy samples indicated that tumor cell intrinsic factors such as TP53 signaling are associated with resistance to glofitamab, but they may also be interlinked with a diminished effector T-cell profile in resistant tumors and thus represent a poor prognostic factor per se. This integrative biomarker data analysis provides clinical evidence regarding glofitamab's mode of action, supports optimal biological dose selection, and will further guide clinical development. This trial was registered at www.clinicaltrials.gov as #NCT03075696.

A Method for the Elution of Anti-CD20 With an EDTA/Glycine Acid Solution for Accurate Immunophenotyping of B Lymphocytes Sensitized With Rituximab.

OBJECTIVES: To assess the efficacy of a method to circumvent CD20-positive antigen masking by rituximab for flow cytometry analysis of B-cell malignancies in hematology patients. METHODS: Mononuclear cells (MNCs) from 10 healthy individuals and 5 untreated patients with B-cell malignancies were sensitized with rituximab. Patients' diagnoses included chronic lymphocytic leukemia, hairy cell leukemia, and follicular lymphoma. MNCs were isolated by gradient density centrifugation. An EDTA/glycine acid (EGA) elution method was used to dissociate CD20-rituximab complexes; afterwards, CD20-positive immunoreactivity was assessed by flow cytometry. A saturation curve was built based on serial dilutions of rituximab. Median fluorescent intensities of CD20-positive signals were obtained before sensitization with rituximab and after its elution with EGA. RESULTS: CD20-positive signals were not detectable by flow cytometry after rituximab sensitization of B cells. CD20-sensitized vs CD20-unsensitized, CD20-sensitized vs CD20-eluted, and CD20-eluted vs CD20-negative control (NC) MNC populations exhibited statistical differences (P = .001), while CD20-sensitized vs CD20-NC populations did not (P = .499), confirming CD20 antigen masking by rituximab. CONCLUSIONS: Rituximab interfered with the flow cytometry protocol for CD20 determination on normal and neoplastic B cells. The EGA method efficiently eluted rituximab, allowing for accurate identification of CD20-positive B cells.

[Subendocardial injury with no evidence of atherosclerosis associated with obinutuzumab infusion]. / Injuria subendocárdica sin evidencia de aterosclerosis relacionada con infusión de obinutuzumab.

Obinutuzumab is a fully humanized monoclonal antibody against CD20 used in the treatment of chronic lymphocytic leukemia. Fatal cardiovascular events have been described, but only in patients with known cardiovascular records. We report the case of an adult male with a high-risk chronic lymphocytic leukemia who developed subendocardial injury, with no evidence of coronary atherosclerosis, during the first administration of obinutuzumab.

El obinutuzumab es un anticuerpo monoclonal completamente humanizado contra CD20, empleado en el tratamiento de leucemia linfocítica crónica. Los eventos cardiovasculares fatales han sido descritos, pero solo en pacientes con antecedentes cardiovasculares conocidos. Presentamos el caso de un hombre adulto con diagnóstico de leucemia linfocítica crónica de alto riesgo que desarrolló injuria subendocárdica, sin evidencia de aterosclerosis coronaria, durante la primera infusión de obinutuzumab.

The future of antibody therapy in chronic lymphocytic leukemia.

INTRODUCTION: Outcomes in chronic lymphocytic leukemia (CLL) have been dramatically improved with the addition of anti-CD20 antibodies to chemotherapy, defining a new standard of care for many years. More recently, therapies targeting fundamental signaling and anti-apoptotic pathways within the CLL cell have demonstrated dramatic clinical responses, including in patients with high-risk prognostic markers, thus emerging as preferred therapy for many patients. While the addition of anti-CD20 antibodies to traditional chemotherapy resulted in significant improvements in outcomes, the role of monoclonal antibodies in the era of targeted agents remains an active area of investigation. Furthermore, since the advent of next-generation anti-CD20 antibodies, the role of specific anti-CD20 antibodies remains an open question. AREAS COVERED: In this review, we highlight the important role that anti-CD20 antibody therapy has had in the field of CLL, both when used with chemotherapy and in combination with targeted therapy, as well as the current studies that are further exploring this treatment paradigm in the modern era. EXPERT OPINION: While anti-CD20 antibodies have played a pivotal role in the treatment of CLL, additional studies will be required to determine the optimal application of these therapies in combination with targeted therapy.

Reassessment of Anti-CD20 Therapy in Lymphoid Malignancies: Impact, Limitations, and New Directions.

The addition of anti-CD20 monoclonal antibodies to the treatment of B-cell malignancies has dramatically affected the field as well as the lives of patients. Rituximab in particular has been combined safely with conventional chemotherapy and has resulted in improved overall survival in major histologic subtypes of B-cell lymphoma and chronic lymphocytic leukemia. It is incorporated into the standard initial treatment of nearly all of these diseases. Novel anti-CD20 antibodies are currently under development. Two of these agents, ofatumumab and obinutuzumab, have been approved for use in certain clinical settings. Research comparing these newer antibodies with rituximab is ongoing. As these newer antibodies are further studied and developed, improvements in response and progression-free survival need to be considered in the context of clinical benefit as well as toxicity, especially in indolent diseases. Research involving rituximab biosimilars is ongoing as well, and recent preliminary data demonstrate similar efficacy and tolerability when compared with rituximab. An additional focus of ongoing research is the use of extended schedules of anti-CD20 monoclonal antibodies, as the optimal duration of therapy remains ill-defined in many histologic subtypes. To maximize the use of these agents, well-validated clinical trial endpoints will need to be carefully considered.

Converting Lymphoma Cells into Potent Antigen-Presenting Cells for Interferon-Induced Tumor Regression.

Anti-hCD20 is a therapeutic mAb that is clinically used to treat B-cell lymphoma. Some lymphomas are resistant to anti-hCD20; others relapse after treatment with anti-hCD20. Using a syngeneic immunocompetent mouse model, we observed that targeting lymphoma with interferon-α (IFNα) abolished resistance of B-cell lymphoma to anti-CD20 while limiting interferon (IFN)-associated systemic toxicity in the host. Control of tumors by a fusion of anti-CD20 and IFNα (anti-CD20-IFNα) depended on existing tumor-infiltrating CD8+ T cells. Although lymphomas were resistant to IFN-directed killing, IFN-exposed tumor cells became the dominant antigen-presenting cells (APC) for the reactivation of tumor-infiltrating CD8+ T cells that then controlled those lymphomas. Anti-CD20-IFNα also abolished checkpoint blockade resistance in advanced B-cell lymphoma. Our findings indicate that anti-CD20-IFNα eradicates B-cell lymphoma by employing tumor cells as APCs to reactivate tumor-infiltrating CD8+ T cells and synergizing with anti-PD-L1 treatment. Cancer Immunol Res; 5(7); 560-70. ©2017 AACR.

Eficacia y seguridad del uso de tofacitibini en el tratamiento de artritis reumatoide refractaria a Anti-TNF y Anti-CD20 / Efficacy and safety of the use of tofacitibini in the treatment of rheumatoid arthritis refractory to Anti-TNF and Anti-CD20

INTRODUCCIÓN: Antecedentes: El presente dictamen expone la evaluación de tecnología de la eficacia y seguridad tofacitinib en pacientes con artritis reumatoide con falla a tratamiento con anti-TNF y anti-CD20. Aspcetos Generales: La artritis reumatoide (AR) es un tipo de poliatritis periférica de naturaleza inflamatória y simétrica. Esta condición suele llevar a una deformación de las articulaciones a través de la erosión de cartilagos y hesos. La ausencia de un tratamiento eficaz, la inflamación y la destrucción de las articulaciones lleva la pérdida de las funciones motoras, y por tanto a la incapacidad de llevar a cabotareas cotidians, e incluso a dificuldades en el ámbito laboral. Tecnología Sanitaria de Interés: El tratamiento de AR incluye como prímera linea el uso de glucocorticoides y fármacos modificadores de la enfermedad (FARMEs) sintético. Si no se obtiene una respuesta adecuada con estos FARMEs sintéticos, es recomendable pasar al uso de agentes biológico, siendo los anti-TNF considerados como la primera opición por la alta tasa de respuesta asoiada a su uso. METODOLOGÍA: Estrategia de Búsqueda: Se realizó una búsqueda de literatura publicada sobre tofacitinib en el tratamiento de Artritis Reumatoide en las bases de datos: medline y Tripdabase. Adicionalmente, se realizaron búsquedas en los portales web de entidades que realizan revisiones sistemáticas, evaluaciones de tecnologías sanitarias y guías de práctica clínica: The Cochrane Library, National Institute for Helath and Care Excellence (NICE) del Reino Unido, American College of Rheumatology, European League Against Rheumatism, Revista Brasileira de Reumatologia, Canadian Agency for Drugs and Technologies in Health. RESUlTADOS: Sinopsis de la Evidencia: Guías de práctica Clínica: Se identificó una GPC de NICE del 2015 la cual redirecciona al lector hacia las evaluaciones de tecnología sanitaria publicadas por NICE sobre los diferentes agentes en el tratamiento de AR, las cuales fueron revisadas e incluidas en los resultados cuando fue pertinente. Evaluaciones de tecnología santiaria: Se incluyó en los resultados una revisión rápida de Canadian Agency for Drugs and Technologies in Health del 2015. Una ETS de NICE sobre tofacitinib se encuentra en desarrollo y se espera que esta sea publicada en el 2018. Revisiones sistemáticas con o sin meta-análisis: Se incluyó una revisión sistemática con meta-análisis de ensayos clínicos controlados, aleatorizados y doble ciego del 2013, y un análisis de data agregada del 2015. Adicionalmente, se incluyeron tres estudios que evaluaron únicamente seguridad: un análisis de dataagregada del 2014, un meta-análisis del 2015, y un análisis del 2017. Ensayos clínicos aleatorizados de fase III. Se incluyó en ECA de fase III del 2013. Adicionalmente, como sugerencia del especialista, se agregó un ECA de fase III del 2012. Resumen de congreso: A sugerencia del especialista se incluyó en los resultados un resumen del congreso del 2016. CONCLUSIONES: A la fecha no se han publicado ensayos clínicos aleatorizados del uso de tofacitinib en una población de pacientes con falla a tratamiento (primaria, secundaria o intolerancia) tanto a anti-TNFs como a anti-CD20. Las GPC identificadas presentan recomendaciones heterogéneas sobre el uso de tofacitinib. A pesar de ello, se puede concluir que, de acuerdo con las GPC, tofacitinib es considerado una alternativa tanto en pacientes que han fallado a tres o más tratamientos biológicos, como en aquellos que han fallado a uno; sin embargo, la mayoria de las GPC concuerdan en que el uso de tofacitinib se debe limitar a aquella población que ha agotado las opciones disponibles de tratamiento biológico, debido principalmente a la escasa información sobre el perfil de seguridad de tofacitinib y su efectos a largo plazo. Debido a que no es clara la relación riesgo/benefício y que existen otras alternativas que han probado ser eficaces para la misma condición (pacientes con AR con respuesta inadecuada a FARMEs biológicos) disponibles en el mercado peruano; a la fecha no se cuenta con evidencia que sustente que el uso de tofacitinib en la población de pacientes con respuesta inadecuada a mas de dos tratamientos biológicos suponga un benefício adicional al tratamiento utilizado actualmente, ni que se trate de un medicamento seguro para los pacientes. Asimismo, vale resaltar que las GPC internacionales identificadas mencionan otras posibles alternativas para la condición mencionada, e incluso algunas de ellas recomiendan otras alternativas por encima de tofacitinib, en línea con la preocupación ralacionada a su perfil de seguridad, y recomiendan reservar su uso únicamente para la población que ha agotado las opciones de tratamiento biológico disponibles en el mercado. El Instituto de Evaluación de Tecnologías en Salud e Investigación-IETSI, no aprueba el uso de tofacitinib en pacientes con AR que han fallado a tratamiento con anti-TNF y con anti-CD20.

Overcoming rituximab drug-resistance by the genetically engineered anti-CD20-hIFN-α fusion protein: Direct cytotoxicity and synergy with chemotherapy.

Treatment of patients with B-NHL with rituximab and CHOP has resulted in significant clinical responses. However, a subset of patients develops resistance to further treatments. The mechanism of unresponsiveness in vivo is not known. We have reported the development of rituximab-resistant clones derived from B-NHL cell lines as models to investigate the mechanism of resistance. The resistant clones exhibit hyper-activated survival/anti-apoptotic pathways and no longer respond to a combination of rituximab and drugs. Recent studies reported the therapeutic efficacy in mice bearing B-cell lymphoma xenografts following treatment with the anti-CD20-hIFNα fusion protein. We hypothesized that the fusion protein may bypass rituximab resistance and inhibit survival signaling pathways. Treatment of the rituximab-resistant clones with anti-CD20-hIFNα, but not with rituximab, IFNα, or rituximab+IFNα resulted in significant inhibition of cell proliferation and induction of cell death. Treatment with anti-CD20-hIFNα sensitized the cells to apoptosis by CDDP, doxorubicin and Treanda. Treatment with anti-CD20-hIFNα inhibited the NF-κB and p38 MAPK activities and induced the activation of PKC-δ and Stat-1. These effects were corroborated by the use of the inhibitors SB203580 (p38 MAPK) and Rottlerin (PKC-δ). Treatment with SB203580 enhanced the sensitization of the resistant clone by anti-CD20-hIFNα to CDDP apoptosis. In contrast, treatment with Rotterin inhibited significantly the sensitization induced by anti-CD20-hIFNα. Overall, the findings demonstrate that treatment with anti-CD20-hIFNα reverses resistance of B-NHL. These findings suggest the potential application of anti-CD20-hIFNα in combination with drugs in patients unresponsive to rituximab-containing regimens.

Primary central nervous system lymphoma: current state of anti-CD20 therapy and appraisal of reported response criteria.

Primary central nervous system lymphoma (PCNSL) is an aggressive non-Hodgkin's lymphoma which is confined to the central nervous system and may also affect intraocular structures. Despite high initial rates of response to methotrexate-based chemotherapy, more than 50% of patients will experience relapse and about 10% have disease that is refractory to chemotherapy. Outcome in patients who fail treatment is very poor, and therefore new therapeutic approaches that may increase the rate of complete response and the proportion of durable remission are sought. Based on the pivotal role that anti-CD20 therapy now plays in the treatment outcome of aggressive systemic B-cell lymphomas, a similar approach is commonly being adapted for PCNSL despite the lack of evidence for its effectiveness. This review examines the current status and level of evidence for the use of monoclonal antibodies against the CD20 surface antigen, which is present on normal and malignant B-cells in PCNSL. The review covers both systemic and local (intracerebrospinal fluid or intravitreal) administration of CD20 monoclonal antibodies in PCNSL. In addition, it scrutinizes the response criteria commonly reported for evaluation of treatment outcome. The importance of differentiating unconfirmed complete response from partial response is outlined and the lack of consensus on response criteria for atypical imaging presentations of PCNSL is delineated.