RESUMO
Addressing inflammation, demyelination, and associated neurodegeneration in inflammatory demyelinating diseases like multiple sclerosis (MS) remains challenging. ACT-1004-1239, a first-in-class and potent ACKR3 antagonist, currently undergoing clinical development, showed promise in preclinical MS models, reducing neuroinflammation and demyelination. However, its effectiveness in treating established disease and impact on remyelination after the occurrence of demyelinated lesions remain unexplored. This study assessed the therapeutic effect of ACT-1004-1239 in two demyelinating disease models. In the proteolipid protein (PLP)-induced experimental autoimmune encephalomyelitis (EAE) model, ACT-1004-1239 administered upon the detection of the first signs of paralysis, resulted in a dose-dependent reduction in EAE disease severity, concomitant with diminished immune cell infiltrates in the CNS and reduced demyelination. Notably, efficacy correlated with elevated plasma concentrations of CXCL11 and CXCL12, two pharmacodynamic biomarkers of ACKR3 antagonism. Combining ACT-1004-1239 with siponimod, an approved immunomodulatory treatment for MS, synergistically reduced EAE severity. In the cuprizone-induced demyelination model, ACT-1004-1239 administered after 5 weeks of cuprizone exposure, significantly accelerated remyelination, already quantifiable one week after cuprizone withdrawal. Additionally, ACT-1004-1239 penetrated the CNS, elevating brain CXCL12 concentrations. These results demonstrate that ACKR3 antagonism significantly reduces the severity of experimental demyelinating diseases, even when treatment is initiated therapeutically, after the occurrence of lesions. It confirms the dual mode of action of ACT-1004-1239, exhibiting both immunomodulatory effects by reducing neuroinflammation and promyelinating effects by accelerating myelin repair. The results further strengthen the rationale for evaluating ACT-1004-1239 in clinical trials for patients with demyelinating diseases.
Assuntos
Encefalomielite Autoimune Experimental , Camundongos Endogâmicos C57BL , Remielinização , Animais , Encefalomielite Autoimune Experimental/tratamento farmacológico , Remielinização/efeitos dos fármacos , Camundongos , Feminino , Doenças Desmielinizantes/tratamento farmacológico , Doenças Desmielinizantes/induzido quimicamente , Cuprizona , Azetidinas/farmacologia , Azetidinas/uso terapêutico , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/uso terapêutico , Compostos de Benzil/uso terapêutico , Compostos de Benzil/farmacologia , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/metabolismoRESUMO
AIMS: The C-X-C chemokine receptor 3 (CXCR3) axis is highly upregulated in the tissue of patients with type 1 diabetes. Antagonizing CXCR3 may reduce the migration of CXCR3-expressing cells to the pancreas. The pharmacokinetics (PKs), target engagement (TE) (inhibition of CXCR3 internalization) and safety of single- and multiple-ascending doses (SADs and MADs) of ACT-777991, a novel orally available potent CXCR3 antagonist, were assessed in a double-blind, randomized, placebo-controlled phase 1 study. METHODS: Doses up to 100 mg (SAD part) and 40 mg twice daily (MAD part) were investigated in a total of 70 male and female healthy participants. Food effect was integrated as an SAD subpart. PK, TE, safety and tolerability data were collected up to 4 days after (last) dosing. RESULTS: In both SAD and MAD parts, ACT-777991 was rapidly absorbed with a time to reach maximum concentration between 0.5 and 1.5 h post dose, followed by a biphasic disposition with a terminal half-life between 9.7 and 10.3 h. Increase in exposure and maximum concentration of ACT-777991 were dose-proportional. Steady state was reached after 48 h with minimal accumulation. The rate but not the extent of absorption was modified by food intake. A dose-dependent TE was demonstrated in both SAD and MAD parts. ACT-777991 was well tolerated. Neither a treatment-related pattern nor a dose-response relationship was determined for adverse events or any safety variable. No QT prolongation liability of regulatory concern was detected. CONCLUSIONS: In this first-in-human study, ACT-777991 showed good tolerability for all doses tested and a PK and TE profile suitable for further clinical development.
Assuntos
Meia-Vida , Adulto , Humanos , Masculino , Feminino , Relação Dose-Resposta a Droga , Área Sob a Curva , Método Duplo-Cego , Voluntários Saudáveis , Administração OralRESUMO
Treatment of patients with recent-onset type 1 diabetes with an anti-CD3 antibody leads to the transient stabilization of C-peptide levels in responder patients. Partial efficacy may be explained by the entry of islet-reactive T-cells spared by and/or regenerated after the anti-CD3 therapy. The CXCR3/CXCL10 axis has been proposed as a key player in the infiltration of autoreactive T cells into the pancreatic islets followed by the destruction of ß cells. Combining the blockade of this axis using ACT-777991, a novel small-molecule CXCR3 antagonist, with anti-CD3 treatment may prevent further infiltration and ß-cell damage and thus, preserve insulin production. The effect of anti-CD3 treatment on circulating T-cell subsets, including CXCR3 expression, in mice was evaluated by flow cytometry. Anti-CD3/ACT-777991 combination treatment was assessed in the virally induced RIP-LCMV-GP and NOD diabetes mouse models. Treatments started at disease onset. The effects on remission rate, blood glucose concentrations, insulitis, and plasma C-peptide were evaluated for the combination treatment and the respective monotherapies. Anti-CD3 treatment induced transient lymphopenia but spared circulating CXCR3+ T cells. Combination therapy in both mouse models synergistically and persistently reduced blood glucose concentrations, resulting in increased disease remission rates compared to each monotherapy. At the study end, mice in disease remission demonstrated reduced insulitis and detectable plasma C-peptide levels. When treatments were initiated in non-severely hyperglycemic NOD mice at diabetes onset, the combination treatment led to persistent disease remission in all mice. These results provide preclinical validation and rationale to investigate the combination of ACT-777991 with anti-CD3 for the treatment of patients with recent-onset diabetes.
Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Camundongos , Animais , Camundongos Endogâmicos NOD , Glicemia , Peptídeo C , Anticorpos Monoclonais/uso terapêutico , Modelos Teóricos , Receptores CXCR3RESUMO
One of the most important advantages of mass spectrometry is the ability to quantify proteins and their modifications in parallel to obtain a holistic picture of the protein of interest. Here, we present a hybrid immunoaffinity targeted mass spectrometry (MS) method that combines efficient pan-antibody enrichment of a specific protein from plasma with the selectivity of high-resolution targeted MS analysis to quantitate specific proteoforms of interest. We used this approach to quantify plasma levels of the chemokine CXCL10 that has been associated with many immunological disorders such as systemic lupus erythematosus and primary Sjögren's Syndrome (pSS). The hybrid approach enabled sensitive, specific, and simultaneous quantification of total, full-length (active) CXCL101-77 and DPP4-truncated (inactive) CXCL103-77 in human plasma down to the low pg/mL level, reaching ELISA sensitivities. Samples from 30 control subjects and 34 pSS patients (n = 64) were analyzed. The ratio of CXCL101-77 to truncated CXCL103-77 was significantly increased in patients with pSS and provided the highest correlation with pSS disease activity. Therefore, this CXCL10 proteoform ratio represents an interesting exploratory disease activity biomarker to further investigate. As this strategy can be readily adapted to other plasma proteins and proteoforms of interest, we are convinced that it will lead to a more detailed understanding of proteoforms in physiology and pathology yielding more relevant biomarkers and drug targets.
Assuntos
Lúpus Eritematoso Sistêmico , Síndrome de Sjogren , Biomarcadores , Quimiocina CXCL10/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Espectrometria de Massas , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/genéticaRESUMO
BACKGROUND: Asthma patients present with distinct immunological profiles, with a predominance of type 2 endotype. The aim of this study was to investigate the impact of high-altitude treatment on the clinical and immunological response in asthma. METHODS: Twenty-six hospitalized asthma patients (nine eosinophilic allergic; EA, nine noneosinophilic allergic; NEA and eight noneosinophilic nonallergic; NN) and nine healthy controls in high altitude for 21 days were enrolled in the study. We assessed eosinophils, T cells, Tregs, and innate lymphoid cells (ILC) from peripheral blood using flow cytometry. RESULTS: The number of eosinophils (both resting and activated) and chemoattractant receptor homolog expressed on Th2 cells (CRTH2)-expressing CD4+ and CD8+ T cells decreased significantly in EA patients after altitude treatment. The frequency of CRTH2+ Tregs as decreased significantly in all the asthma phenotypes as well as the frequency of ILC2 was significantly reduced in EA after altitude treatment. After 21 days of altitude therapy, CRTH2-expressing ILC2, CD4+ and CD8+ T cells and Treg cells showed attenuated responses to exogenous PGD2. Furthermore, PGD2 signaling via CRTH2 was found to diminish the suppressive function of CRTH2+ Tregs which partially normalized during high-altitude treatment. Improved asthma control was particularly evident in allergic asthma patients and correlated with decreased frequencies of CRTH2+ Treg cells in EA patients. Serum IL-5 and IL-13 decreased during climate treatment in asthma patients with high baseline levels. CONCLUSIONS: Asthma treatment in high altitude reduced the type 2 immune response, corrected the increased CRTH2 expression and its dysregulated functions.
Assuntos
Altitude , Asma/imunologia , Linfócitos/imunologia , Receptores Imunológicos/imunologia , Receptores de Prostaglandina/imunologia , Células Th2/imunologia , Adulto , Feminino , Humanos , Masculino , Subpopulações de Linfócitos T/imunologiaRESUMO
The endothelin (ET) system has emerged as a novel target for hypertension treatment where a medical need persists despite availability of several pharmacological classes, including renin angiotensin system (RAS) blockers. ET receptor antagonism has demonstrated efficacy in preclinical models of hypertension, especially under low-renin conditions and in hypertensive patients. We investigated the pharmacology of aprocitentan (N-[5-(4-bromophenyl)-6-[2-[(5-bromo-2-pyrimidinyl)oxy]ethoxy]-4-pyrimidinyl]-sulfamide), a potent dual ETA/ETB receptor antagonist, on blood pressure (BP) in two models of experimental hypertension: deoxycorticosterone acetate (DOCA)-salt rats (low-renin model) and spontaneously hypertensive rats [(SHR), normal renin model]. We also compared the effect of its combination with RAS blockers (valsartan and enalapril) with that of the combination of the mineraloreceptor antagonist spironolactone with the same RAS blockers on BP and renal function in hypertensive rats. Aprocitentan was more potent and efficacious in lowering BP in conscious DOCA-salt rats than in SHRs. In DOCA-salt rats, single oral doses of aprocitentan induced a dose-dependent and long-lasting BP decrease and 4-week administration of aprocitentan dose dependently decreased BP (statistically significant) and renal vascular resistance, and reduced left ventricle hypertrophy (nonsignificant). Aprocitentan was synergistic with valsartan and enalapril in decreasing BP in DOCA-salt rats and SHRs while spironolactone demonstrated additive effects with these RAS blockers. In hypertensive rats under sodium restriction and enalapril, addition of aprocitentan further decreased BP without causing renal impairment, in contrast to spironolactone. In conclusion, ETA/ETB receptor antagonism represents a promising therapeutic approach to hypertension, especially with low-renin characteristics, and could be used in combination with RAS blockers, without increasing the risk of renal impairment.
Assuntos
Anti-Hipertensivos/administração & dosagem , Antagonistas dos Receptores de Endotelina/administração & dosagem , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Pirimidinas/administração & dosagem , Sistema Renina-Angiotensina/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Animais , Anti-Hipertensivos/farmacologia , Acetato de Desoxicorticosterona/toxicidade , Quimioterapia Combinada , Antagonistas dos Receptores de Endotelina/farmacologia , Hipertensão/induzido quimicamente , Masculino , Pirimidinas/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Sistema Renina-Angiotensina/fisiologia , Sulfonamidas/farmacologiaRESUMO
AIMS: Eosinophilic oesophagitis (EoE) is a chronic inflammatory disease characterised clinically by symptoms of oesophageal dysfunction and histopathologically by a prominent eosinophilic inflammation. Despite eosinophils having a histologically predominant position, their role in the immunopathogenesis of the disease is still questionable. Several other inflammatory cells are involved and may also play a critical role. The purpose of this study was to characterise the mast cell infiltration, and to correlate it with the clinical state of EoE. METHODS AND RESULTS: Using immunohistochemistry and quantitative morphometry, we investigated eosinophils and mast cells extensively in oesophageal biopsies from patients with active EoE and from patients with EoE in remission, and compared the findings with healthy individuals. In EoE, epithelium and lamina propria were similarly infiltrated with eosinophils. In contrast, mast cells infiltration was limited to the epithelium, displaying a localised immune response. Interestingly, whereas epithelial mast cells and eosinophils were high in active EoE, some patients in remission, e.g. normalised epithelial eosinophils, showed remaining high numbers of mast cells. Patient clustering supported two groups of patients in clinical remission, differentiating based on presence or absence of epithelial mast cells. CONCLUSIONS: Active EoE is characterised in addition to the well-known tissue eosinophilia by a marked epithelium-restricted mast cell infiltration. Of interest, in a subgroup of patients, mast cell infiltration persisted despite clinical remission. To elucidate the clinical consequence of persistent epithelial mast cells infiltration further studies are required following patients in clinical remission longitudinally.
Assuntos
Esofagite Eosinofílica/imunologia , Esofagite Eosinofílica/patologia , Mastócitos/imunologia , Mastócitos/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Nanoparticles are increasingly suspected as a strong etiologic factor of granuloma formation. AIM OF THE STUDY: The aim of our study was to compare lung inflammatory response and histology changes following exposure of mice to two widely used nanoparticles: carbon nanotubes (MWCNT) and cadmium-based nanoparticles (QDOT705) in an attempt to better our understanding of granulomatous inflammation. MATERIALS AND METHODS: Various groups of mice were included: control mice and mice that were intranasally instilled with QDOT or MWCNT. At defined time points post-challenge, bronchoalveolar lavages (BALs) and lung tissues were collected to study inflammatory and histologic changes. RESULTS: Analyses of lung BAL fluids and tissues of nanoparticles-challenged mice in comparison to controls found: (1) increased cellularity in BALs, (2) increase of total protein concentration, LDH activity and proteolytic activity in BALs; (3) patchy granulomas, (4) macrophages, CD3 ± T, Treg and B cell infiltration in granulomatous areas; and (5) altered regulation of key inflammatory mediators and receptors. Importantly, these changes were nanoparticle type-dependent. CONCLUSION: Our work enhances understanding of nanoparticles-induced lung inflammatory and histological changes that result in granuloma formation. We provide compelling evidence that not only exposure to nanoparticles leads to granulomatous lung inflammation, but the severity of this latter is nanostructure type-dependent. Of importance, while nanotechnology has the potential to revolutionize various fields including medicine, nanoparticles form the potential for an entirely new lung health risk that it is necessary to take seriously into consideration by setting up and/or reinforcing adequate safety measures.
Assuntos
Granuloma/patologia , Nanopartículas/efeitos adversos , Pneumonia/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Cádmio/efeitos adversos , Granuloma/etiologia , Camundongos , Nanopartículas/química , Nanotubos de Carbono/efeitos adversos , Pneumonia/etiologiaRESUMO
Endothelin (ET) receptor antagonists have been associated with fluid retention. It has been suggested that, of the two endothelin receptor subtypes, ETB receptors should not be blocked, because of their involvement in natriuresis and diuresis. Surprisingly, clinical data suggest that ETA-selective antagonists pose a greater risk of fluid overload than dual antagonists. The purpose of this study was to evaluate the contribution of each endothelin receptor to fluid retention and vascular permeability in rats. Sitaxentan and ambrisentan as ETA-selective antagonists and bosentan and macitentan as dual antagonists were used as representatives of each class, respectively. ETA-selective antagonism caused a dose-dependent hematocrit/hemoglobin decrease that was prevented by ETB-selective receptor antagonism. ETA-selective antagonism led to a significant blood pressure reduction, plasma volume expansion, and a greater increase in vascular permeability than dual antagonism. Isolated vessel experiments showed that ETA-selective antagonism increased vascular permeability via ETB receptor overstimulation. Acutely, ETA-selective but not dual antagonism activated sympathetic activity and increased plasma arginine vasopressin and aldosterone concentrations. The hematocrit/hemoglobin decrease induced by ETA-selective antagonism was reduced in Brattleboro rats and in Wistar rats treated with an arginine vasopressin receptor antagonist. Finally, the decrease in hematocrit/hemoglobin was larger in the venous than in the arterial side, suggesting fluid redistribution. In conclusion, by activating ETB receptors, endothelin receptor antagonists (particularly ETA-selective antagonists) favor edema formation by causing: 1) fluid retention resulting from arginine vasopressin and aldosterone activation secondary to vasodilation, and 2) increased vascular permeability. Plasma volume redistribution may explain the clinical observation of a hematocrit/hemoglobin decrease even in the absence of signs of fluid retention.
Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Antagonistas dos Receptores de Endotelina/farmacologia , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Aldosterona/metabolismo , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Arginina Vasopressina/metabolismo , Bosentana , Endotelinas/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Hematócrito/métodos , Hemoglobinas/metabolismo , Masculino , Fenilpropionatos/farmacologia , Piridazinas/farmacologia , Pirimidinas/farmacologia , Ratos , Ratos Brattleboro , Ratos Wistar , Receptores de Vasopressinas/metabolismo , Sulfonamidas/farmacologia , Vasodilatação/efeitos dos fármacosRESUMO
AIMS: The main objectives of these two phase I studies were to investigate safety and tolerability as well as the pharmacokinetic/pharmacodynamic profile of the novel potent and selective formyl peptide receptor type 2 (FPR2)/Lipoxin A4 receptor (ALX) agonist ACT-389949. A challenge model was used to assess the drug's anti-inflammatory potential, with the aim of selecting a dosing regimen for future patient studies. METHODS: Two double-blind, randomized phase I studies investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of ACT-389949 at different doses and dosing regimens. Drug exposure was correlated with target engagement markers such as receptor internalization and cytokine measurements. The effect of FPR2/ALX agonism on neutrophil migration was studied in a lipopolysaccharide (LPS) inhalation model. RESULTS: ACT-389949 was well tolerated. Maximum concentrations were reached around 2 h after dosing, with a mean terminal half-life of 29.3 h [95% confidence interval (CI) 25.5, 33.7]. After multiple-dose administration, exposure increased by 111% (95% CI 89, 136), indicating drug accumulation. Administration of ACT-389949 resulted in a dose-dependent, long-lasting internalization of FPR2/ALX into leukocytes. Pro- and anti-inflammatory cytokines were dose-dependently but transiently upregulated only after the first dose. No pharmacological effect on neutrophil count was observed in the LPS challenge test performed at steady state. CONCLUSIONS: FPR2/ALX agonism with ACT-389949 was shown to be safe and well tolerated in healthy subjects. Receptor internalization and downstream mediators pointed towards a desensitization of the system, which may explain the lack of effect on neutrophil recruitment in the LPS challenge model.
Assuntos
Oxazóis/efeitos adversos , Oxazóis/farmacologia , Oxazóis/farmacocinética , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Triazóis/efeitos adversos , Triazóis/farmacologia , Triazóis/farmacocinética , Adolescente , Adulto , Animais , Biomarcadores , Ensaios de Migração Celular , Citocinas/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Inflamação/induzido quimicamente , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Adulto JovemRESUMO
PURPOSE: This analysis aimed at describing the effect of the selective sphingosine-1-phosphate receptor 1 modulator ponesimod on lymphocyte subsets in peripheral blood. As the involvement of different lymphocyte subsets varies among different autoimmune diseases, characterizing the effect of ponesimod on these may be beneficial in better understanding treatment effects. METHODS: Three phase 1 clinical studies in healthy human subjects were pooled. Non-linear mixed-effects modeling techniques were used to study the effect of ponesimod on lymphocyte subsets such as B cells, T helper cells, T cytotoxic cells, and natural killer cells in a qualitative and quantitative manner. RESULTS: Indirect-response Imax models including circadian variation best described the effect of ponesimod on lymphocyte subsets. B cells and T helper cells were shown to be more affected compared to T cytotoxic cells with respect to the maximum possible reduction (100% for B and T helper cells, 95% for T cytotoxic cells) and the concentration required to reach half the maximum effect. Inter-individual variability was found to be larger for T cytotoxic compared to T helper, and B cells. CONCLUSION: These first models for ponesimod on the level of lymphocyte subsets offer a valuable tool for the analysis and interpretation of results from ponesimod trials in autoimmune diseases.
Assuntos
Subpopulações de Linfócitos/efeitos dos fármacos , Receptores de Lisoesfingolipídeo/metabolismo , Tiazóis/farmacologia , Adolescente , Adulto , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Ritmo Circadiano , Simulação por Computador , Relação Dose-Resposta a Droga , Feminino , Humanos , Contagem de Linfócitos , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Tiazóis/química , Adulto JovemRESUMO
Niemann-Pick disease type C (NP-C) is a rare, autosomal-recessive, progressive neurological disease caused by mutations in either the NPC1 gene (in 95% of cases) or the NPC2 gene. This observational, multicentre genetic screening study evaluated the frequency and phenotypes of NP-C in consecutive adult patients with neurological and psychiatric symptoms. Diagnostic testing for NP-C involved NPC1 and NPC2 exonic gene sequencing and gene dosage analysis. When available, results of filipin staining, plasma cholestane-3ß,5α,6ß-triol assays and measurements of relevant sphingolipids were also collected. NPC1 and NPC2 gene sequencing was completed in 250/256 patients from 30 psychiatric and neurological reference centres across the EU and USA [median (range) age 38 (18-90) years]. Three patients had a confirmed diagnosis of NP-C; two based on gene sequencing alone (two known causal disease alleles) and one based on gene sequencing and positive filipin staining. A further 12 patients displayed either single mutant NP-C alleles (8 with NPC1 mutations and 3 with NPC2 mutations) or a known causal disease mutation and an unclassified NPC1 allele variant (1 patient). Notably, high plasma cholestane-3ß,5α,6ß-triol levels were observed for all NP-C cases (n = 3). Overall, the frequency of NP-C patients in this study [1.2% (95% CI; 0.3%, 3.5%)] suggests that there may be an underdiagnosed pool of NP-C patients among adults who share common neurological and psychiatric symptoms.
Assuntos
Proteínas de Transporte/genética , Testes Genéticos , Glicoproteínas/genética , Glicoproteínas de Membrana/genética , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Niemann-Pick Tipo C/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Alelos , Feminino , Variação Genética , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Mutação , Proteína C1 de Niemann-Pick , Doença de Niemann-Pick Tipo C/fisiopatologia , Doença de Niemann-Pick Tipo C/psicologia , Fenótipo , Análise de Sequência de DNA , Proteínas de Transporte Vesicular , Adulto JovemRESUMO
The CXCR3 chemokine receptor is a G protein-coupled receptor mainly expressed on immune cells from the lymphoid lineage, including activated T cells. Binding of its inducible chemokine ligands CXCL9, CXCL10, and CXCL11 leads to downstream signaling events and the migration of activated T cells to sites of inflammation. Herein, we report the third part of our CXCR3 antagonist program in the field of autoimmunity, culminating in the discovery of the clinical compound ACT-777991 (8a). A previously disclosed advanced molecule was exclusively metabolized by the CYP2D6 enzyme, and options to address the issue are described. ACT-777991 is a highly potent, insurmountable, and selective CXCR3 antagonist that showed dose-dependent efficacy and target engagement in a mouse model of acute lung inflammation. The excellent properties and safety profile warranted progress in the clinics.
Assuntos
Quimiocina CXCL10 , Receptores de Quimiocinas , Animais , Camundongos , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9 , Receptores de Quimiocinas/metabolismo , Ligantes , Transdução de Sinais , Receptores CXCR3/metabolismoRESUMO
GM2 and GM1 gangliosidoses are genetic, neurodegenerative lysosomal sphingolipid storage disorders. The earlier the age of onset, the more severe the clinical presentation and progression, with infantile, juvenile and late-onset presentations broadly delineated into separate phenotypic subtypes. Gene and substrate reduction therapies, both of which act directly on sphingolipidosis are entering clinical trials for treatment of these disorders. Simple to use biomarkers for disease monitoring are urgently required to support and expedite these clinical trials. Here, lysosphingolipid and protein biomarkers of sphingolipidosis and neuropathology respectively, were assessed in plasma samples from 33 GM2 gangliosidosis patients, 13 GM1 gangliosidosis patients, and compared to 66 controls. LysoGM2 and lysoGM1 were detectable in 31/33 GM2 gangliosidosis and 12/13 GM1 gangliosidosis patient samples respectively, but not in any controls. Levels of the axonal damage marker Neurofilament light (NF-L) were highly elevated in both GM2 and GM1 gangliosidosis patient plasma samples, with no overlap with controls. Levels of the astrocytosis biomarker Glial fibrillary acidic protein (GFAP) were also elevated in samples from both patient populations, albeit with some overlap with controls. In GM2 gangliosidosis patient plasma NF-L, Tau, GFAP and lysoGM2 were all most highly elevated in infantile onset patients, indicating a relationship to severity and phenotype. Plasma NF-L and liver lysoGM2 were also elevated in a GM2 gangliosidosis mouse model, and were lowered by treatment with a drug that slowed disease progression. These results indicate that lysosphingolipids and NF-L/GFAP have potential to monitor pharmacodynamics and pathogenic processes respectively in GM2 and GM1 gangliosidoses patients.
RESUMO
Loss of control in the trafficking of immune cells to the inflamed lung tissue contributes to the pathogenesis of life-threatening acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS). Targeting CXCR7 has been proposed as a potential therapeutic approach to reduce pulmonary inflammation; however, its role and its crosstalk with the two chemokine receptors CXCR3 and CXCR4 via their shared ligands CXCL11 and CXCL12 is not yet completely understood. The present paper aimed to characterize the pathological role of the CXCR3/CXCR4/CXCR7 axis in a murine model of ALI. Lipopolysaccharide (LPS) inhalation in mice resulted in the development of key pathologic features of ALI/ARDS, including breathing dysfunctions, alteration in the alveolar capillary barrier, and lung inflammation. LPS inhalation induced immune cell infiltration into the bronchoalveolar space, including CXCR3+ and CXCR4+ cells, and enhanced the expression of the ligands of these two chemokine receptors. The first-in-class CXCR7 antagonist, ACT-1004-1239, increased levels of CXCL11 and CXCL12 in the plasma without affecting their levels in inflamed lung tissue, and consequently reduced CXCR3+ and CXCR4+ immune cell infiltrates into the bronchoalveolar space. In the early phase of lung inflammation, characterized by a massive influx of neutrophils, treatment with ACT-1004-1239 significantly reduced the LPS-induced breathing pattern alteration. Both preventive and therapeutic treatment with ACT-1004-1239 reduced lung vascular permeability and decreased inflammatory cell infiltrates. In conclusion, these results demonstrate a key pathological role of CXCR7 in ALI/ARDS and highlight the clinical potential of ACT-1004-1239 in ALI/ARDS pathogenesis.
RESUMO
The C-X-C chemokine receptor 7 (CXCR7) has evolved as a promising, druggable target mainly in the immunology and oncology fields modulating plasma concentrations of its ligands CXCL11 and CXCL12 through receptor-mediated internalization. This "scavenging" activity creates concentration gradients of these ligands between blood vessels and tissues that drive directional cell migration. This randomized, double-blind, placebo-controlled first-in-human study assessed the safety, tolerability, pharmacokinetics, and pharmacodynamics of ACT-1004-1239, a first-in-class drug candidate small-molecule CXCR7 antagonist. Food effect and absolute bioavailability assessments were also integrated in this multipurpose study. Healthy male subjects received single ascending oral doses of ACT-1004-1239 (n = 36) or placebo (n = 12). At each of six dose levels (1-200 mg), repeated blood sampling was done over 144 hours for pharmacokinetic/pharmacodynamic assessments using CXCL11 and CXCL12 as biomarkers of target engagement. ACT-1004-1239 was safe and well tolerated up to the highest tested dose of 200 mg. CXCL12 plasma concentrations dose-dependently increased and more than doubled compared with baseline, indicating target engagement, whereas CXCL11 concentrations remained unchanged. An indirect-response pharmacokinetic/pharmacodynamic model well described the relationship between ACT-1004-1239 and CXCL12 concentrations across the full dose range, supporting once-daily dosing for future clinical studies. At doses ≥ 10 mg, time to reach maximum plasma concentration ranged from 1.3 to 3.0 hours and terminal elimination half-life from 17.8 to 23.6 hours. The exposure increase across the dose range was essentially dose-proportional and no relevant food effect on pharmacokinetics was determined. The absolute bioavailability was 53.0% based on radioactivity data after oral vs. intravenous 14 C-radiolabeled microtracer administration of ACT-1004-1239. Overall, these comprehensive data support further clinical development of ACT-1004-1239.
Assuntos
Quimiocina CXCL12/sangue , Receptores CXCR/antagonistas & inibidores , Adulto , Disponibilidade Biológica , Biomarcadores/sangue , Quimiocina CXCL11/sangue , Relação Dose-Resposta a Droga , Interações Alimento-Droga , Meia-Vida , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Sphingosine-1-phosphate (S1P), a lipid mediator, regulates lymphocyte migration between lymphoid tissue and blood. Furthermore, S1P participates in several physiological phenomena including angiogenesis, inflammation, immune regulation, and neurotransmitter release. Moreover, S1P/S1P receptor signaling involves in systemic sclerosis (SSc) pathogenesis. This study aimed to investigate whether the selective S1P1 receptor modulator cenerimod attenuates murine sclerodermatous models. Cenerimod was orally administered to murine sclerodermatous chronic graft versus host disease (Scl-cGVHD) mice, either from day 0 to 42 or day 22 to 42 after bone marrow transplantation. Bleomycin-induced SSc model mice were administered cenerimod from day 0 to 28. Early cenerimod administration inhibited, and delayed cenerimod administration attenuated skin and lung fibrosis in Scl-cGVHD mice. Cenerimod suppressed the infiltration of CD4+ T cells, CD8+ T cells, and CD11b+ cells into the inflamed skin of Scl-cGVHD mice as opposed to control mice. In contrast, cenerimod increased the frequency of regulatory T cells in the spleen and skin of Scl-cGVHD mice. Additionally, cenerimod attenuated the mRNA expression of extracellular matrix and fibrogenic cytokines in the skin. Furthermore, cenerimod attenuated bleomycin-induced fibrosis in the skin and lung. Hence, the selective S1P1 receptor modulator cenerimod is a promising candidate for treating patients with SSc and Scl-cGVHD.
Assuntos
Oxidiazóis/metabolismo , Propilenoglicóis/metabolismo , Escleroderma Sistêmico/tratamento farmacológico , Receptores de Esfingosina-1-Fosfato/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Contagem de Células , Colágeno/biossíntese , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose , Doença Enxerto-Hospedeiro/tratamento farmacológico , Masculino , Camundongos , Oxidiazóis/farmacologia , Propilenoglicóis/farmacologia , RNA Mensageiro/genética , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismoRESUMO
BACKGROUND AND OBJECTIVE: The chemoattractant receptor-homologous molecule expressed on T helper-2 cells (CRTH2) is a G-protein-coupled receptor for prostaglandin D2 (PGD2), a key mediator in inflammatory disorders. Two selective and potent CRTH2 antagonists currently in clinical development, ACT-453859 and setipiprant, were compared with respect to their (predicted) clinical efficacy. METHODS: Population pharmacokinetic (PK) and pharmacodynamic (PD) models were developed to characterize how plasma concentrations (PK) of ACT-453859, its active metabolite ACT-463036 and setipiprant related to their effect on blocking PGD2-induced internalization of CRTH2 on eosinophils (PD). Simulations were used to identify doses and dosing regimens leading to 90 % of maximum blockade of CRTH2 internalization at trough. RESULTS: A combined concentration of ACT-453859 and its metabolite ACT-463036, with weights proportional to potency (based on an eosinophil shape change assay), enabled good characterization of the PD effect. The modelling and simulation results facilitated decision making by suggesting an ACT-453859 dose of 400 mg once daily (or 100 mg twice daily) for clinically relevant CRTH2 antagonism. CONCLUSION: Pharmacometric quantification demonstrated that CRTH2 internalization is a useful new biomarker to study CRTH2 antagonism. Ninety percent of maximum blockade of CRTH2 internalization at trough is suggested as a quantitative PD target in clinical studies.
Assuntos
Acetatos/farmacologia , Carbazóis/farmacologia , Eosinófilos/metabolismo , Indóis/farmacologia , Naftalenos/farmacologia , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Acetatos/farmacocinética , Carbazóis/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Meia-Vida , Humanos , Indóis/farmacocinética , Taxa de Depuração Metabólica , Naftalenos/farmacocinéticaRESUMO
The monoclonal antibody GSLA-2 recognizes the sialyl Lewis(a) (sLe(a)) epitope, which has an increased occurrence on mucin type glycoproteins of patients with colorectal carcinoma. GSLA-2 is therefore used in tumor diagnosis. To advance the understanding of this highly specific molecular recognition reaction, we have analyzed the binding epitope of sLe(a) at atomic resolution using saturation transfer difference NMR. To compare, the binding epitopes of sialyl Lewis(x) (sLe(x)) and of four synthetic derivatives of sLe(a) were explored. Surface plasmon resonance experiments furnished thermodynamic and kinetic data. It is observed that all pyranose rings of sLe(a) are in contact with the protein surface, with the neuramic acid residue receiving the largest fraction of saturation transfer. In contrast, sLe(x) binds very weakly, though specifically to GSLA-2, with a different binding epitope. This study provides a comprehensive picture of the recognition sLe(a) and explains the exquisite specificity of the antibody.