Excessive Biologic Response to IFNβ Is Associated with Poor Treatment Response in Patients with Multiple Sclerosis

Interferon-beta (IFNβ) is used to inhibit disease activity in multiple sclerosis (MS), but its mechanisms of action are incompletely understood, individual treatment response varies, and biological markers predicting response to treatment have yet to be identified.he relationship between the molecular response to IFNβ and treatment response was determined in 85 patients using a longitudinal design in which treatment effect was categorized by brain magnetic resonance imaging as good (n = 70) or poor response (n = 15). Molecular response was quantified using a customized cDNA macroarray assay for 166 IFN-regulated genes (IRGs).The molecular response to IFNβ differed significantly between patients in the pattern and number of regulated genes. The molecular response was strikingly stable for individuals for as long as 24 months, however, suggesting an individual ‘IFN response fingerprint’. Unexpectedly, patients with poor response showed an exaggerated molecular response. IRG induction ratios demonstrated an exaggerated molecular response at both the first and 6-month IFNβ injections.MS patients exhibit individually unique but temporally stable biological responses to IFNβ. Poor treatment response is not explained by the duration of biological effects or the specific genes induced. Rather, individuals with poor treatment response have a generally exaggerated biological response to type 1 IFN injections. We hypothesize that the molecular response to type I IFN identifies a pathogenetically distinct subset of MS patients whose disease is driven in part by innate immunity. The findings suggest a strategy for biologically based, rational use of IFNβ for individual MS patients

Multiple sclerosis -the impact of environmental- and lifestyle factors

Background: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS), likely caused by an interaction of genetic and environmental factors. Epstein-Barr virus infection, low serum vitamin D levels, smoking and obesity increase the risk of MS. However, knowledge of their effect on disease activity and progression have been limited. Objective: The main objective was to explore the role of different environmental and lifestyle factors for MS disease activity. In more detail, we sought to evaluate whether there is an association between tobacco use or body mass index (BMI) and MS disease activity. We also explored the potential of two adipokines, leptin and adiponectin as biomarkers for disease course or interferon-beta (IFNβ) treatment response in MS. Methods: All data in our studies were based on the OFAMS study, a randomized placebo-controlled multicenter study of 92 patients with relapsing-remitting MS (RRMS) that was conducted between 2004 -2008. The patients were followed for 24 months with repeated magnetic resonance imaging (MRI) of the brain, blood tests and clinical evaluations, 6 months prior to and 18 months during IFNβ-treatment. For the current thesis, we analyzed serum samples for cotinine, a biomarker for tobacco use, and the adipokines leptin and adiponectin. For the first study, the patients were categorized as tobacco-users and non-tobacco-users according to their serum cotinine level. For the second and third study, patients were categorized based on the World Health Organisation (WHO) classification of BMI into three groups; normal weight patients (BMI30 kg/m²). All analyses were adjusted for age, gender and BMI. Results: We did not find any association between tobacco use and MRI activity (paper I). Further, there was no difference between tobacco users and non-tobacco users regarding baseline Expanded Disability Status Scale (EDSS) score, EDSS-progression or relapse-rate. For tobacco users, there was no correlation between serum cotinine levels and disease activity. There was no difference in clinical and MRI activity between patients stratified by BMI prior to IFNβ-treatment. During IFNβ-treatment, 80 % of overweight or obese patients had MRI activity compared to 48 % in the group of normal weight patients (p=0.001). The number of patients obtaining NEDA (no evidence of disease activity)-status differed according to BMI; 26 % in the normal weight group compared to only 13 % in the group of overweight and obese patients (p=0.05) (paper II). There was no association between serum levels of leptin or adiponectin and MRI disease activity (paper III). The serum levels of leptin were lower and the levels of adiponectin higher during IFNβ-treatment compared to the treatment-naïve period, reflecting the anti-inflammatory effect of the drug. Conclusion: In our studies, we found no direct association between tobacco use or BMI and MS disease activity. During IFNβ-treatment fewer of the overweight and obese patients obtained NEDA-status compared to patients with normal weight, indicating that BMI could affect IFNβ-treatment response. Serum levels of leptin and adiponectin seem not to be suited as biomarkers for disease activity or IFNβ-treatment response in MS.Doktorgradsavhandlin

Monocyte NOTCH2 expression predicts interferon-beta immunogenicity in multiple sclerosis patients

Multiple sclerosis (MS) is an autoimmune disease characterized by CNS inflammation leading to demyelination and axonal damage. IFN-β is an established treatment for MS; however, up to 30% of IFN-β–treated MS patients develop neutralizing antidrug antibodies (nADA), leading to reduced drug bioactivity and efficacy. Mechanisms driving antidrug immunogenicity remain uncertain, and reliable biomarkers to predict immunogenicity development are lacking. Using high-throughput flow cytometry, NOTCH2 expression on CD14+ monocytes and increased frequency of proinflammatory monocyte subsets were identified as baseline predictors of nADA development in MS patients treated with IFN-β. The association of this monocyte profile with nADA development was validated in 2 independent cross-sectional MS patient cohorts and a prospective cohort followed before and after IFN-β administration. Reduced monocyte NOTCH2 expression in nADA+ MS patients was associated with NOTCH2 activation measured by increased expression of Notch-responsive genes, polarization of monocytes toward a nonclassical phenotype, and increased proinflammatory IL-6 production. NOTCH2 activation was T cell dependent and was only triggered in the presence of serum from nADA+ patients. Thus, nADA development was driven by a proinflammatory environment that triggered activation of the NOTCH2 signaling pathway prior to first IFN-β administration

Unraveling treatment response in multiple sclerosis: A clinical and MRI challenge

Over the last few decades, the improved diagnostic criteria, the wide use of MRI, and the growing availability of effective pharmacologic treatments have led to substantial advances in the management of multiple sclerosis (MS). The importance of early diagnosis and treatment is now well-Established, but there is still no consensus on how to define and monitor response to MS treatments. In particular, the clinical relevance of the detection of minimal MRI activity is controversial and recommendations on how to define and monitor treatment response are warranted. An expert panel of the Magnetic Resonance Imaging in MS Study Group analyzed and discussed published studies on treatment response in MS. The evolving concept of no evidence of disease activity and its effect on predicting long-term prognosis was examined, including the option of defining a more realistic target for daily clinical practice: minimal evidence of disease activity. Advantages and disadvantages associated with the use of MRI activity alone and quantitative scoring systems combining on-treatment clinical relapses and MRI active lesions to detect treatment response in the real-world setting were also discussed. While most published studies on this topic involved patients treated with interferon-\u3b2, special attention was given to more recent studies providing evidence based on treatment with other and more efficacious oral and injectable drugs. Finally, the panel identified future directions to pursue in this research field

Vasculitis, Autoimmunity, and Cytokines: How the Immune System Can Harm the Brain

More and more findings suggest that neurological disorders could have an immunopathological cause. Thus, immune-targeted therapies are increasingly proposed in neurology (even if often controversial), as anakinra, inhibiting IL-1 for febrile inflammatory illnesses, and JAK inhibitors for anti-interferons treatment. Precision medicine in neurology could be fostered by a better understanding of the disease machinery, to develop a rational use of immuno-modulators in clinical trials. In this review, we focus on monogenic disorders with neurological hyper-inflammation/autoimmunity as simplified "models" to correlate immune pathology and targeted treatments. The study of monogenic models yields great advantages for the elucidation of the pathogenic mechanisms that can be reproduced in cellular/animal models, overcoming the limitations of biological samples to study. Moreover, monogenic disorders provide a unique tool to study the mechanisms of neuroinflammatory and autoimmune brain damage, in all their manifestations. The insight of clinical, pathological, and therapeutic aspects of the considered monogenic models can impact knowledge about brain inflammation and can provide useful hints to better understand and cure some neurologic multifactorial disorders

Pharmacogenomics of Multiple Sclerosis: A Systematic Review

Background: Over the past two decades, various novel disease-modifying drugs for multiple sclerosis (MS) have been approved. However, there is high variability in the patient response to the available medications, which is hypothesized to be partly attributed to genetics. Objectives: To conduct a systematic review of the current literature on the pharmacogenomics of MS therapy. Methods: A systematic literature search was conducted using PubMed/MEDLINE database searching for articles investigating a role of genetic variation in response to disease-modifying MS treatments, published in the English language up to October 9th, 2018. PRISMA guidelines for systematic reviews were applied. Studies were included if they investigated response or nonresponse to MS treatment defined as relapse rate, by expanded disability status scale score or based on magnetic resonance imaging. The following data were extracted: first author's last name, year of publication, PMID number, sample size, ethnicity of patients, method, genes, and polymorphisms tested, outcome, significant associations with corresponding P-values and confidence intervals, response criteria, and duration of the follow-up period. Results: Overall, 48 articles published up to October 2018, evaluating response to interferon-beta, glatiramer acetate, mitoxantrone, and natalizumab, met our inclusion criteria and were included in this review. Among those, we identified 42 (87.5%) candidate gene studies and 6 (12.5%) genome-wide association studies. Existing pharmacogenomic evidence is mainly based on the results of individual studies, or on results of multiple studies, which often lack consistency. In recent years, hypothesis-free approaches identified novel candidate genes that remain to be validated. Various study designs, including the definition of clinical response, duration of the follow-up period, and methodology as well as moderate sample sizes, likely contributed to discordances between studies. However, some of the significant associations were identified in the same genes, or in the genes involved in the same biological pathways. Conclusions: At the moment, there is no available clinically actionable pharmacogenomic biomarker that would enable more personalized treatment of MS. More large-scale studies with uniform design are needed to identify novel and validate existing pharmacogenomics findings. Furthermore, studies investigating associations between rare variants and treatment response in MS patients, using next-generation sequencing technologies are warranted

Differences in innate immune response between man and mouse

Mouse strains are frequently used to model human disease states, to test the efficiency of drugs and therapeutic principles. However, the direct translation of murine experimental data to human pathological events often fails due to sufficient differences in the organization of the immune system of both species. Here we give a short overview of the principle differences between mice and humans in defense strategies against pathogens and mechanisms involved in response to pathogenic microorganisms and other activators of the immune system. While in human blood mechanisms of immune resistance are highly prevailed, tolerance mechanisms dominate for the defense against pathogenic microorganisms in mouse blood. Further on, species-related differences of immune cells mainly involved in innate immune response as well as differences to maintain oxidative homeostasis are also considered. A number of disease scenarios in mice are critically reflected for their suitability to serve as a model for human pathologies. Due to setbacks in these studies, novel mouse models were created to bridge the immune system of both species: humanized mice. Accordingly, a special section of this review is devoted to new results applying humanized mouse models taking limitations and prospects into account

The neonatal anti-viral response fails to control measles virus spread in neurons despite interferon-gamma expression and a Th1-like cytokine profile

Neonates are highly susceptible to infections in the central nervous system (CNS) and have a greater risk of viral infections and encephalopathies. Neurotropic viral infections can lead to blindness, hearing loss and neurological deficiencies such as cognitive impairment, epilepsy, and even death in the neonatal and pediatric populations. Viral infections also are hypothesized to indirectly contribute to neurodegenerative and neuropsychiatric diseases such as Schizophrenia and Parkinson’s disease later in life due to early neuronal damage or stress. Many diverse viruses are capable of invading the neonatal CNS including Borna Disease Virus, Coxsackievirus (CV), Herpes simplex viruses (HSV), and measles virus. Although, we understand that many viruses can cause CNS disease, the mechanisms of viral pathogenesis in the brain and the character of the neonatal anti-viral immune response are not well understood. However, it is hypothesized that neurological damage results from the combined effect of the virus and the immune response. Therefore, it is critical to develop immune-mediated strategies to promote viral clearance from the CNS while preventing neuronal damage or loss. This remains a challenge during neonatal CNS infections because of the uniquely immature nature of the neonatal immune system and the sensitivity of developing neurons to inflammation. In order to better understand how the neonatal immune response behaves in the brain, we use neurotropic measles virus (MV) as a model to understand the deficits in the neonatal immunity. Measles is a single-stranded, negative-sense RNA virus that is highly contagious in humans. Typical infection involves inhalation of infected respiratory droplets, infection of dendritic cells and macrophages in the respiratory tract resulting in transient immunosuppression, and a characteristic fever and rash. However, in some cases, MV also causes severe neurological diseases such as Post-infectious encephalomyelitis (PIE), Subacute sclerosing panencephalitis (SSPE), and Measles inclusion body encephalitis (MIBE). Currently, there is no cure for these MV-related neurological conditions, which occur overwhelmingly in newborns and children. Thus, the goal of this project is to define how neonatal immunity responds to MV infection in the unique microenvironment of the brain. The role of interferon-gamma (IFNg), a key anti-viral cytokine in controlling adult CNS infections, was explored during a neuronally-restricted MV infection in the neonatal brain. We hypothesized that neonatal mice would be deficient in either IFNg production or in the infiltration of IFNg-producing immune cells in the brain. In order to address this question, we utilized the CD46+ mouse model, in which the human CD46+ receptor for MV is expressed only in mature neurons of the CNS. We explored the differences in the neonatal immune response, where the mice succumb to MV infection, and compared that to the CD46+ adults, which successfully control MV and survive. Our findings suggest that IFNg, which is critical for viral control and survival in adults, only delays mortality in CD46+ neonates. The neonatal brains also show the infiltration of natural killer cells, neutrophils, infiltrating monocytes and T cells in an IFNg-independent manner, all of which are capable of contributing to the IFNg pool. However, neonates and adults differentially express pathogen recognition receptors (e.g. Toll-like receptors) and Type I interferons during infection in the CNS, which suggests that the initial recognition of the virus by the immune system may differ in an age-dependent manner. Both neonates and adults expressed IFNg, CXCL10, IL-1, and IL-1RA, among other cytokines/chemokines. Regardless, CD46+ neonates succumb to infection despite mounting a Th1-like, but apparently defective, inflammatory response. We further explored whether there are age-dependent differences in IFNg signalling given that both ages of mice expressed this critical cytokine. Both neonatal and adult CD46+ mice express similar levels of IFNg but only adults show robust induction of the IFNg-responsive genes CIITA and CXCL9. This suggests that IFNg signaling may be defective in the induction of IFNg-responsive genes in neonates compared to adults. To dissect the role of individual components of the immune system, we utilized CD46+ mice crossed to specific immune knockouts: CD46+/IFNg-KO mice, which lack IFNg, and CD46+/RAG2-KO mice, which lack mature B and T cells. We found that neonates lacking IFNg succumbed more rapidly than wildtype CD46+ mice, while neonates lacking mature B and T cells showed delayed morbidity and mortality. Neonates without IFNg show high infiltration of neutrophils and inflammatory monocytes but similar numbers of NK cell infiltration compared to CD46+ neonates. CD46+/IFNg-KO neonatal brains also show high infiltration of CD4 and CD8 T cells at the later stages of MV infection. Additionally, IFNα is significantly upregulated in the absence of IFNg in the brain post-MV infection. Thus, compensatory cytokines and high immune cell infiltration may contribute to uncontrolled inflammation and earlier death in CD46+/IFNg-KO neonates. CD46+ mice deficient in T-cells and B-cells (CD46+/RAG2-KO) show prolonged survival and mount a robust IFNβ response post-MV infection. This suggests that the adaptive immune response may be detrimental during the neonatal period, potentially leading to greater tissue damage. Additionally, CD46+/RAG2-KO neonates alone upregulate unique genes such as bone morphogenetic proteins (BMPs), which may mediate neuroprotection. Thus, these results suggest age-dependent expression of cytokine profiles in the brain and distinct dynamic interplays between lymphocyte populations and cytokines/chemokines in MV-infected neonates

Gelatinases, Neurofilaments and N-Acetyl aspartic Acid as Biomarkers in Different Pathologies

Background: Gelatinases (MMP-2 and MMP-9) are zinc and calcium dependent endopeptidases that degrade several components of the extracellular matrix.The role of gelatinases in inflammation seems to be opposite. MMP-9, which can be produced also by neutrophils, has been associated to inflammation in several pathologies; also, the environmental conditions (i.e.pH) might influence the release of MMP-9 from neutrophils. On the contrary, MMP-2 has been associated to both tissue repair and damage, although its role is not yet clear. Furthermore, the possible presence in body fluids of a 66 kDa active form of MMP-9, which might not be modulated by its inhibitor TIMP-1, could open new insights on MMP-9 as marker of inflammation. Neurofilaments (Nf) are normally contained into the axoplasm and are released in the extracellular fluid following axonal injury. N-Acetyl aspartic Acid (NAA) is one of the most abundant molecules in the CNS. Recently, the combination of neurofilaments and NAA was identified as promising marker of axonal damage in Multiple Sclerosis (MS) patients. Aims: In the present study, I aimed to evaluate the role of active MMP-9 and MMP-2 as biomakers in inflammatory conditions (Multiple Sclerosis (MS) and in Spontaneous Intra Cerebral Hemorrhage (SICH)), and the role of Nf light and heavy subunits and NAA as biomarkers of axonal damage in a relatively large cohort of PPMS. I also investigated the presence in serum of the 66 kDa MMP-9, and pH effect on the neutrophils response. Methods: The 66 kDa active MMP-9 form was identified by employing immunoprecipitation and affinity chromatography. Human neutrophils were isolated from buffy-coats and placed in medium at different pH in absence or presence of stimulus (LPS or IL-8). The MMP-9 released was assayed by ELISA. The levels of MMP-9, MMP-2, TIMP-1 and TIMP-2 were measured by activity assay systems and ELISA in serum of 28 SICH patients, whereas only MMP-2 and TIMP-2 were measured in Cerebrospinal fluid (CSF) and serum of 67 patients with RRMS and in 129 controls. NAA, Nf light and Nf heavy were assayed by GC-MS, Luminex and ELISA, respectively, in CSF of 28 Primary Progressive (PP) and 10 Transitional Progressive MS patients and 15 controls. Main Results: The separation of MMP-9 from MMP-2 by affinity chromatography and immunoprecipitation showed that the 66 kDa form of MMP-9 is present in serum of healthy donors. MMP-9 release increased when neutrophils were placed in medium at acid pH, whereas it was uneffected by alkaline conditions. CSF and serum values of active MMP-2/TIMP-2 ratios as well as intrathecal synthesis of active MMP-2 were higher in MS patients than in non-inflammatory conditions and in Magnetic Resonance Imaging (MRI) inactive than in MRI active patients. Serum levels of active MMP-9 and MMP-2 as well as Perihematomal Edema (PE) volume were significantly different over time in SICH patients: MMP-9 and PE volume increase, whereas MMP- 2 decreases. Nf heavy levels were two fold higher in progressive MS patients. NAA levels were negatively correlated with black hole volume. Combined biomarkers classified an higher number of patients with abnormal biomarker levels than single markers. Conclusions: The presence of the 66 kDa active MMP-9 in the serum of healthy donors opens the possibility to investigate the role of this form also in pathological conditions. The different neutrophil response to environmental pH changes strengthen the hypothesis of MMP- 9 as marker of inflammation. The results obtained in this study about MMP-9 and MMP-2 in patients affected by SICH and MS, suggest that the two gelatinases may have opposite roles in inflammation. While MMP-9 enhance the inflammation, MMP-2 seems associated to its resolution. CSF Nf isoforms and NAA may reflect various aspects of axonal damage in Multiple Sclerosis. In particular, Nf heavy can be considered as a specific marker of axonal damage accumulation in patients with essentially progressive MS course

The clinical relevance of drug immunogenicity

Tese de doutoramento, Medicina (Reumatologia), Universidade de Lisboa, Faculdade de Medicina, 2015The introduction of biologic therapies into clinical practice has greatly improved the treatment of chronic disabling inflammatory diseases, such as Rheumatoid Arthritis, Spondylarthritis or Inflammatory Bowel Diseases, among others. However, a sizeable fraction of patients never achieve therapeutic response or, more often, cannot maintain therapeutic response over time. Among the pitfalls of biologicals is their potential immunogenicity and the associated anti-drug antibodies (ADAb) produced by the patients, which promote faster clearance/neutralization of the drug in circulation and thus interfere with drug efficacy. Moreover, ADAb have also been associated with adverse events. In this work we aimed at formally document the impact of ADAb in clinical outcomes, and use this analysis to construct and test an algorithm for therapeutic decisions based on explicit biomarkers of immunogenicity. To evaluate the clinical relevance of biological drug’s immunogenicity, we first performed a systematic review of the literature coupled with a meta-analysis. We evidenced that in the presence of detectable ADAb therapeutic response may be reduced by as much as 80%. Such impact is attenuated, although not abrogated, by concomitant immunosuppression, particularly with methotrexate that associates with reduced ADAb production. Differences in the immunogenic profile of specific biologics were also verified, with monoclonal antibodies exhibiting higher immunogenicity than fusion proteins. We next assessed the impact of immunogenicity on drug’s safety profile by following a cohort of patients receiving intravenous infliximab, a TNF-inhibitor. Infusion-related adverse events occurred exclusively in ADAb-positive patients and nearly half of the ADAb-positive patients developed an acute reaction during or immediately after the infusion, requiring medical intervention. To evaluate the relevance of drug immunogenicity assessment for therapeutic decisions, we first defined a convenient method to assess immunogenicity on a routine basis. We verified that a newly developed Bridging ELISA performed as well as antigen-binding radio-immuno assay, currently considered by many as the “gold-standard” to assess ADAb. Next, we designed an algorithm for the management of patients receiving biologic therapies, which combines the usual clinical evaluation with immunogenicity assessment at every three months. This algorithm was tested in a cohort of RA patients treated with one of the three most commonly used biologics. We evidenced that patients who followed therapeutic strategies concordant with the proposed algorithm had close to 10-times higher probability of achieving low disease activity, when compared to those who followed other strategies commonly adopted in current clinical practice. Our work demonstrates that a personalized, evidence-based approach for the management of patients receiving biologic therapies will lead to safer and most cost-effective strategies. These findings have important clinical, societal and economic consequences.As terapêuticas biológicas revolucionaram o prognóstico de doenças inflamatórias crónicas e incapacitantes como a Artrite Reumatóide, as Espondilartrites, as Doenças Inflamatórias do Intestino, entre outras. Ainda assim, um número significativo de doentes não responde a esses fármacos ou, mais frequentemente, perde a resposta inicial ao longo do tempo de tratamento. Uma das principais limitações destas terapêuticas é o seu potencial imunogénico e a consequente formação de anticorpos anti-fármaco (AAF) por parte dos doentes a quem são administrados. Os AAF promovem uma rápida eliminação/neutralização do fármaco em circulação e podem também interferir com o seu perfil de segurança, associando-se a um maior risco de efeitos adversos. Este trabalho pretende documentar formalmente o impacto clínico dos AAF, utilizando essa informação na construção e validação de um novo algoritmo de apoio à decisão terapêutica baseado em biomarcadores de imunogenicidade. Para avaliar a relevância clínica da imunogenicidade foi inicialmente realizada uma revisão sistemática da literatura e uma meta-análise. Evidenciámos que na presença de AAF detetáveis há uma redução de até 80% da resposta à terapêutica. Este impacto é atenuado, mas não eliminado, pelo tratamento concomitante com imunossupressores, particularmente com metotrexato, que se associa a uma redução da produção de AAF. Foram também verificadas diferenças importantes no perfil imunogénico entre os fármacos, com os anticorpos monoclonais a exibirem maior imunogenicidade que as proteinas de fusão. Seguidamente foi avaliado o impacto da imunogenicidade no perfil de segurança destes fármacos, avaliando no tempo uma cohort de doentes tratados com infliximab, um inibidor do TNF-alfa. Reações adversas agudas associadas à infusão do fármaco ocorreram exclusivamente em doentes com AAF detetáveis, sendo que cerca de metade dos doentes com AAF tiveram uma reação aguda durante ou imediatamente após a infusão do biológico, requerendo intervenção médica imediata. No sentido de avaliar a relevância da avaliação da imunogenicidade para a melhoria das decisões terapêuticas, começámos por definir o método laboratorial mais conveniente para monitorização da imunogenicidade na prática clínica de rotina. Constatámos uma boa concordância entre um novo método de ELISA desenvolvido (“Bridging ELISA”) e o método de radioimmunoensaio (“RIA-ABT”), considerado por muitos como “gold standard” na deteção dos indivíduos AAF-positivos. Seguidamente, desenhámos um algoritmo de apoio à decisão terapêutica para doentes medicados com terapêuticas biológicas, que combina a atual avaliação clínica com a monitorização da imunogenicidade a cada três meses. Este algoritmo foi testado numa cohort de doentes com Artrite Reumatóide inicialmente medicados com um dos três agentes biológicos mais utilizados no tratamento desta doença. Evidenciámos que os doentes que tinham seguido estratégias terapêuticas concordantes com o algoritmo proposto tiveram cerca de 10 vezes maior probabilidade de alcançarem uma baixa atividade de doença, quando comparados com os doentes que seguiram outras estratégias, frequentemente adotadas na atual prática clínica. O nosso trabalho demonstra que uma abordagem personalizada e cientificamente orientada aos doentes medicados com terapêuticas biológicas permite desenhar estratégias mais seguras e custo-efetivas. Os nossos resultados têm não só uma elevada relevância clínica, como também económica e social