Impact of DMARD treatment and systemic inflammation on all-cause mortality in patients with rheumatoid arthritis and interstitial lung disease: a cohort study from the German RABBIT register.

OBJECTIVES: To investigate the impact of disease activity and treatment with disease-modifying antirheumatic drugs (DMARDs) on all-cause mortality in patients with rheumatoid arthritis and prevalent interstitial lung disease (RA-ILD). METHODS: Patients with RA-ILD were selected from the biologics register Rheumatoid Arthritis: Observation of Biologic Therapy (RABBIT). Using time-varying Cox regression, the association between clinical measures and mortality was investigated. The impact of DMARDs was analysed by (1) Cox regression considering cumulative exposure (ie, treatment months divided by total months) and (2) time-varying Cox regression as main approach (treatment exposures at monthly level). RESULTS: Out of 15 566 participants, 381 were identified as RA-ILD cases with 1258 person-years of observation and 2.6 years median length of follow-up. Ninety-seven patients (25.5%) died and 34 (35.1%) of these were not receiving DMARD therapy at the time of death. Higher inflammatory biomarkers but not swollen and tender joint count were significantly associated with mortality. Compared with tumour necrosis factor inhibitors (TNFi), non-TNFi biologic DMARDs (bDMARDs) exhibited adjusted HRs (aHRs) for mortality below 1, lacking statistical significance. This finding was stable in various sensitivity analyses. Joint aHR for non-TNFi biologics and JAKi versus TNFi was 0.56 (95% CI 0.33 to 0.97). Receiving no DMARD treatment was associated with a twofold higher mortality risk compared with receiving any DMARD treatment, aHR 2.03 (95% CI 1.23 to 3.35). CONCLUSIONS: Inflammatory biomarkers and absence of DMARD treatment were associated with increased risk of mortality in patients with RA-ILD. Non-TNFi bDMARDs may confer enhanced therapeutic benefits in patients with RA-ILD.

The protective effect of tumor necrosis factor-alpha inhibitors in COVID-19 in patients with inflammatory rheumatic diseases compared to the general population-A comparison of two German registries.

Objectives: To investigate, whether inflammatory rheumatic diseases (IRD) inpatients are at higher risk to develop a severe course of SARS-CoV-2 infections compared to the general population, data from the German COVID-19 registry for IRD patients and data from the Lean European Survey on SARS-CoV-2 (LEOSS) infected patients covering inpatients from the general population with SARS-CoV-2 infections were compared. Methods: 4310 (LEOSS registry) and 1139 cases (IRD registry) were collected in general. Data were matched for age and gender. From both registries, 732 matched inpatients (LEOSS registry: n = 366 and IRD registry: n = 366) were included for analyses in total. Results: Regarding the COVID-19 associated lethality, no significant difference between both registries was observed. Age > 65°years, chronic obstructive pulmonary disease, diabetes mellitus, rheumatoid arthritis, spondyloarthritis and the use of rituximab were associated with more severe courses of COVID-19. Female gender and the use of tumor necrosis factor-alpha inhibitors (TNF-I) were associated with a better outcome of COVID-19. Conclusion: Inflammatory rheumatic diseases (IRD) patients have the same risk factors for severe COVID-19 regarding comorbidities compared to the general population without any immune-mediated disease or immunomodulation. The use of rituximab was associated with an increased risk for severe COVID-19. On the other hand, the use of TNF-I was associated with less severe COVID-19 compared to the general population, which might indicate a protective effect of TNF-I against severe COVID-19 disease.

A Call for Gene Expression Analysis in Whole Blood of Patients With Rheumatoid Arthritis (RA) as a Biomarker for RA-Associated Interstitial Lung Disease.

OBJECTIVE: Rheumatoid arthritis (RA)-associated interstitial lung disease (ILD) is one of the most common and prognostic organ manifestations of RA. Therefore, to allow effective treatment, it is of crucial importance to diagnose RA-ILD at the earliest possible stage. So far, the gold standard of early detection has been high-resolution computed tomography (HRCT) of the lungs. This procedure involves considerable radiation exposure for the patient and is therefore unsuitable as a routine screening measure for ethical reasons. Here, we propose the analysis of characteristic gene expression patterns as a biomarker to aid in the early detection and initiation of appropriate, possibly antifibrotic, therapy. METHODS: To investigate unique molecular patterns of RA-ILD, whole blood samples were taken from 12 female patients with RA-ILD (n = 7) or RA (n = 5). The RNA was extracted, sequenced by RNA-Seq, and analyzed for characteristic differences in the gene expression patterns between patients with RA-ILD and those with RA without ILD. RESULTS: The differential gene expression analysis revealed 9 significantly upregulated genes in RA-ILD compared to RA without ILD: arginase 1 (ARG1), thymidylate synthetase (TYMS), sortilin 1 (SORT1), marker of proliferation Ki-67 (MKI67), olfactomedin 4 (OLFM4), baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5), membrane spanning 4-domains A4A (MS4A4A), C-type lectin domain family 12 member A (CLEC12A), and the long intergenic nonprotein coding RNA (LINC02967). CONCLUSION: All gene products of these genes (except for LINC02967) are known from the literature to be involved in the pathogenesis of fibrosis. Further, for some, a contribution to the development of pulmonary fibrosis has even been demonstrated in experimental studies. Therefore, the results presented here provide an encouraging perspective for using specific gene expression patterns as biomarkers for the early detection and differential diagnosis of RA-ILD as a routine screening test.

Learning single-cell perturbation responses using neural optimal transport.

Understanding and predicting molecular responses in single cells upon chemical, genetic or mechanical perturbations is a core question in biology. Obtaining single-cell measurements typically requires the cells to be destroyed. This makes learning heterogeneous perturbation responses challenging as we only observe unpaired distributions of perturbed or non-perturbed cells. Here we leverage the theory of optimal transport and the recent advent of input convex neural architectures to present CellOT, a framework for learning the response of individual cells to a given perturbation by mapping these unpaired distributions. CellOT outperforms current methods at predicting single-cell drug responses, as profiled by scRNA-seq and a multiplexed protein-imaging technology. Further, we illustrate that CellOT generalizes well on unseen settings by (1) predicting the scRNA-seq responses of holdout patients with lupus exposed to interferon-ß and patients with glioblastoma to panobinostat; (2) inferring lipopolysaccharide responses across different species; and (3) modeling the hematopoietic developmental trajectories of different subpopulations.

Eosinophilic fasciitis (Shulman syndrome)-recognition of the histological spectrum allows for new insights into possible pathomechanisms.

OBJECTIVES: EF is a rare disease characterized by fibrosis and inflammation of the fascia, scleroderma-like skin indurations and optional blood eosinophilia. We aimed to expand the knowledge about its aetiology and pathogenesis. METHODS: Biopsy specimens from 16 EF patients were assessed by histology, immunohistochemistry and quantitative reverse transcription PCR in comparison with anti-Mi-2+ DM patients and non-disease controls. RESULTS: Histologically, EF shows mild to severe inflammation at the muscle-fascia interface, with frequent involvement of the underlying muscle tissue, though varying in degree. CD206+ macrophages predominate and eosinophils are detected within the fascia in the majority of cases, however in quite small numbers, and seen infrequently within the muscle. Activators of the so-called Th2-M2 pathway like STAT6 and IL-4 are upregulated leading to high expression levels of CD206. Activators of the so-called Th1-M1 pathway like STAT1 and IFN-γ (IFNG) are also upregulated, though not translating into a significant upregulation of the effector molecule COX2. Interestingly, activators or chemoattractants of eosinophils show no significant upregulation in EF compared with DM. EF shows features of perifascicular pathology comparable to DM, with upregulation of MHC class I and II; however, this is not accompanied by perifascicular atrophy or any signs of a type I IFN response or hypoxia-mediated processes. CONCLUSIONS: Our findings highlight a specific immune phenotype of leucocyte infiltrates in EF along features of perifascicular pathology similar to DM, while there is no evidence of hypoxia-mediated or type I IFN-associated processes with perifascicular fibre atrophy, indicating different pathomechanisms of muscle involvement.

Influence of hepatic impairment on the pharmacokinetics and pharmacodynamics of the P2Y12 receptor antagonist selatogrel.

Selatogrel is a potent and selective reversible P2Y12 receptor antagonist in development for early treatment of acute myocardial infarction via subcutaneous (s.c.) self-injection. Selatogrel is almost exclusively eliminated via the hepatobiliary route. Hepatic impairment is associated with reduced drug clearance and primary hemostasis. This single-center, open-label study investigated the effect of mild and moderate hepatic impairment on pharmacokinetics (PK) and pharmacodynamics (PD) of a single s.c. dose of selatogrel (16 mg). The study included groups of eight subjects with mild and moderate hepatic impairment, and matched healthy control subjects. Compared to healthy subjects, exposure to selatogrel in subjects with mild and moderate hepatic impairment was 30% and 108% (maximum plasma concentration [Cmax ]) and 47% and 212% (area under the concentration-time curve from zero to infinity [AUC0-∞ ]) higher, respectively. Hepatic impairment was associated with lower clearance and volume of distribution, whereas plasma protein binding was not affected. Marked inhibition of platelet aggregation (IPA > 80%) was attained within 30 min in all subjects and hepatic impairment prolonged IPA duration. Area under the effect curve was 60% and 160% higher in subjects with mild and moderate hepatic impairment, respectively. PK/PD modeling identified a change in the relationship between exposure and IPA, with a steeper concentration-effect relationship in healthy subjects compared to subjects with hepatic impairment. The combination of higher exposure and lower half-maximum inhibitory concentration resulted in longer lasting effect. In conclusion, hepatic impairment alters the PK/PD relationship leading to prolonged effects. Therefore, dose adjustments may be warranted in subjects with moderate hepatic impairment.

Long-term treatment with streptozocin/5-fluorouracil chemotherapy in patients with metastatic pancreatic neuroendocrine tumors: Case series.

RATIONALE: Pancreatic neuroendocrine tumors (pNETs) are rare entities representing 1% to 3% of all malignant pancreatic neoplasms. Current guidelines recommend a combination of streptozocin (STZ) and 5-fluorouracil (5-FU) for patients with metastatic well-differentiated pNETs requiring systemic therapy. The highest median progression-free survival rate reported in previous studies for this combination was 23 months (95% confidence interval 14.5-31.5). However, it remains unclear for how long this regimen can be safely administered. PATIENT CONCERNS: We report about 3 therapy-naïve patients with metastatic G2 (Ki67 10%-15%) pNETs treated with STZ/5-FU, that achieved sustained disease control for longer than 36 months. DIAGNOSIS: Metastatic, well-differentiated G2 pNETs. INTERVENTIONS: Systemic chemotherapy with STZ/5-FU was administered until the disease progressed. In 1 case showing a mixed response, selected metastases of increasing size were additionally treated with surgery and brachytherapy. OUTCOMES: In our 3 patients with metastatic G2 pNETs, STZ/5-FU induced long-term disease control over 44, 42, and 95 months, respectively. No side effects that led to treatment discontinuation were observed. LESSONS: In patients with metastatic G2 pNETs achieving disease control, STZ/5-FU can be safely administered.

[Modern drug therapy for systemic sclerosis associated interstitial lung disease]. / Moderne medikamentöse Therapie der interstitiellen Lungenerkrankung bei systemischer Sklerose.

Systemic Sclerosis with Interstitial Lung Disease (SSc-ILD) is associated with an increased risk of morbidity and mortality. Because of a lack of approved medications that can effectively influence SSc-ILD disease course, there is a need for new therapeutic options. Treatment with immunomodulatory therapies as well as with autologous stem cell transplant is being further investigated in current clinical studies. Recently, a phase III study demonstrated the positive effect of the antifibrotic agent nintedanib on the loss of lung volume and thus disease progression in patients with SSc-ILD. Due to its synergistic mechanism of action, combination therapy with nintedanib and mycophenolate could be a complementary treatment approach for SSc-ILD in the future.

[Arthritis and pulmonary cavities]. / Arthritiden und Lungenkavernen.

This case report describes the very rare simultaneous occurrence of rheumatoid arthritis and granulomatosis with polyangiitis with the only organ manifestation of life-threatening bilateral pulmonary cavities. Due to the acuteness of the vasculitis, treatment was primarily with cyclophosphamide infusions and high-dose glucocorticoids, and in the further course with high-dose methotrexate. Routine thoracic imaging also seems to be useful when conventional basic rheumatologic treatment is newly initiated, as treatment-decisive changes are seen with a relevant frequency. The occurrence of both autoimmune diseases might be due to common genetic predispositions.

TNFi is associated with positive outcome, but JAKi and rituximab are associated with negative outcome of SARS-CoV-2 infection in patients with RMD.

INTRODUCTION: Several risk factors for severe COVID-19 specific for patients with inflammatory rheumatic and musculoskeletal diseases (RMDs) have been identified so far. Evidence regarding the influence of different RMD treatments on outcomes of SARS-CoV-2 infection is still poor. METHODS: Data from the German COVID-19-RMD registry collected between 30 March 2020 and 9 April 2021 were analysed. Ordinal outcome of COVID-19 severity was defined: (1) not hospitalised, (2) hospitalised/not invasively ventilated and (3) invasively ventilated/deceased. Independent associations between demographic and disease features and outcome of COVID-19 were estimated by multivariable ordinal logistic regression using proportional odds model. RESULTS: 2274 patients were included. 83 (3.6%) patients died. Age, male sex, cardiovascular disease, hypertension, chronic lung diseases and chronic kidney disease were independently associated with worse outcome of SARS-CoV-2 infection. Compared with rheumatoid arthritis, patients with psoriatic arthritis showed a better outcome. Disease activity and glucocorticoids were associated with worse outcome. Compared with methotrexate (MTX), TNF inhibitors (TNFi) showed a significant association with better outcome of SARS-CoV-2 infection (OR 0.6, 95% CI0.4 to 0.9). Immunosuppressants (mycophenolate mofetil, azathioprine, cyclophosphamide and ciclosporin) (OR 2.2, 95% CI 1.3 to 3.9), Janus kinase inhibitor (JAKi) (OR 1.8, 95% CI 1.1 to 2.7) and rituximab (OR 5.4, 95% CI 3.3 to 8.8) were independently associated with worse outcome. CONCLUSION: General risk factors for severity of COVID-19 play a similar role in patients with RMDs as in the normal population. Influence of disease activity on COVID-19 outcome is of great importance as patients with high disease activity-even without glucocorticoids-have a worse outcome. Patients on TNFi show a better outcome of SARS-CoV-2 infection than patients on MTX. Immunosuppressants, rituximab and JAKi are associated with more severe course.

Pharmacokinetic/pharmacodynamic modeling of drug interactions at the P2Y12 receptor between selatogrel and oral P2Y12 antagonists.

Selatogrel is a potent and reversible P2Y12 receptor antagonist developed for subcutaneous self-administration by patients with suspected acute myocardial infarction. After single-dose emergency treatment with selatogrel, patients are switched to long-term treatment with oral P2Y12 receptor antagonists. Selatogrel shows rapid onset and offset of inhibition of platelet aggregation (IPA) to overcome the critical initial time after acute myocardial infarction. Long-term benefit is provided by oral P2Y12 receptor antagonists such as clopidogrel, prasugrel, and ticagrelor. A population pharmacokinetic (PK)/pharmacodynamic (PD) model based on data from 545 subjects in 4 phase I and 2 phase II studies well described the effect of selatogrel on IPA alone and in combination with clopidogrel, prasugrel, and ticagrelor. The PK of selatogrel were described by a three-compartment model. The PD model included a receptor-pool compartment to which all drugs can bind concurrently, reversibly or irreversibly, depending on their mode of action. Furthermore, ticagrelor and its active metabolite can bind to the selatogrel-receptor complex allosterically, releasing selatogrel from the binding site. The model provided a framework for predicting the effect on IPA of selatogrel followed by reversibly and irreversibly binding oral P2Y12 receptor antagonists for sustained effects. Determining the timepoint for switching from emergency to maintenance treatment is critical to achieve sufficient IPA at all times. Simulations based on the interaction model showed that loading doses of clopidogrel and prasugrel administered 15 h and 4.5 h after selatogrel, respectively, provide sustained IPA with clinically negligible drug interaction. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? Selatogrel is a potent reversible P2Y12 receptor antagonist developed for subcutaneous self-administration by patients in case of suspected acute myocardial infarction. Transition to oral P2Y12 receptor antagonists without drug interaction and sufficient inhibition of platelet aggregation must be assured at all times. WHAT QUESTION DID THIS STUDY ADDRESS? The pharmacokinetic/pharmacodynamic model semimechanistically describes the effect of selatogrel on platelet inhibition alone and in combination with the oral P2Y12 receptor antagonists clopidogrel, prasugrel, and ticagrelor. WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? Model-based simulations showed that loading doses of clopidogrel and prasugrel can be administered from 15 h and 4.5 h after selatogrel, respectively. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? These results support guiding the clinical transition from selatogrel emergency treatment to oral maintenance therapy in a safe and efficacious way.

Pulmonary Manifestations of Rheumatoid Arthritis, Psoriatic Arthritis and Peripheral Spondyloarthritis: Prevalence, Diagnostic Approach and Treatment Options.

Interstitial lung disease (ILD) is the most common form of pulmonary impairment in patients with rheumatoid arthritis (RA). However, patients with RA or other arthritic diseases such as psoriatic arthritis (PsA) or peripheral spondyloarthritis (pSpA) are at a higher risk of developing several other pulmonary diseases, such as chronic obstructive lung disease (COPD), compared to patients without arthritis. This review aims at summarizing the current knowledge on the prevalence of pulmonary diseases in the above-mentioned forms of arthritis, the challenges faced by prevalence studies in detecting pulmonary diseases in patients with arthritis, as well as possible treatment options. Dyspnea, cough or other pulmonary symptoms in arthritis patients should prompt gradual diagnostic procedures considering pulmonary manifestations as a major cluster of differential diagnosis. However, treatment options often lack solid evidence-based guidelines and referrals to specialized centers are often necessary.

National registry for patients with inflammatory rheumatic diseases (IRD) infected with SARS-CoV-2 in Germany (ReCoVery): a valuable mean to gain rapid and reliable knowledge of the clinical course of SARS-CoV-2 infections in patients with IRD.

OBJECTIVES: Patients with inflammatory rheumatic diseases (IRD) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be at risk to develop a severe course of COVID-19. The influence of immunomodulating drugs on the course of COVID-19 is unknown. To gather knowledge about SARS-CoV-2 infections in patients with IRD, we established a registry shortly after the beginning of the pandemic in Germany. METHODS: Using an online questionnaire (www.COVID19-rheuma.de), a nationwide database was launched on 30 March 2020, with appropriate ethical and data protection approval to collect data of patients with IRD infected with SARS-CoV-2. In this registry, key clinical and epidemiological parameters-for example, diagnosis of IRD, antirheumatic therapies, comorbidities and course of the infection-are documented. RESULTS: Until 25 April 2020, data from 104 patients with IRD infected with SARS-CoV-2 were reported (40 males; 63 females; 1 diverse). Most of them (45%) were diagnosed with rheumatoid arthritis, 59% had one or more comorbidities and 42% were treated with biological disease-modifying antirheumatic drugs. Hospitalisation was reported in 32% of the patients. Two-thirds of the patients already recovered. Unfortunately, 6 patients had a fatal course. CONCLUSIONS: In a short time, a national registry for SARS-CoV2-infected patients with IRD was established. Within 4 weeks, 104 cases were documented. The registry enables to generate data rapidly in this emerging situation and to gain a better understanding of the course of SARS-CoV2-infection in patients with IRD, with a distinct focus on their immunomodulatory therapies. This knowledge is valuable for timely information of physicians and patients with IRD, and shall also serve for the development of guidance for the management of patients with IRD during this pandemic.

Strategies for the treatment of HBV/HDV.

An estimated 240 million people worldwide are chronically infected with the hepatitis B virus (HBV). Despite readily available vaccination, HBV infections remain highly prevalent. As established HBV infections constitute a strong risk factor for developing hepatocellular carcinoma their treatment is a major task for the health system. Unfortunately, HBV is not curable with today's medicine. Approximately 15 million HBV patients have developed a hepatitis delta (HDV) infection on top of their HBV infection. The patients superinfected with this satellite virus suffer from a more severe disease development. The knowledge of the viruses, their classifications, clinical implications, treatment options and efforts to increase the drug variety are compiled in this review. The current standard therapies include nucleosidic reverse transcriptase inhibitors and interferon. As the known treatments fail to cure HBV and HDV, targeted treatment is highly warranted. The focus of this review is set on the drugs currently under clinical investigation. Furthermore, strategies for the development of targeted treatment, and compounds with novel mode of action are described.

Trends in treatment and outcomes of ankylosing spondylitis in outpatient rheumatological care in Germany between 2000 and 2012.

OBJECTIVES: To describe changes in drug treatment and clinical outcomes of ankylosing spondylitis (AS) during the past decade. METHODS: The national database of the German collaborative arthritis centres collects clinical and patient-derived data from unselected outpatients with inflammatory rheumatic diseases. Cross-sectional data from 2000 to 2012 of around 1000 patients with AS per year were compared with regard to clinical presentation and quality of life indicators. RESULTS: Non-steroidal anti-inflammatory drugs (NSAIDs) have been the predominant treatment choice in AS over the years with a prescription rate of 67% of patients in 2012. Currently, almost half of the patients with AS in German rheumatology centres are treated with tumour necrosis factor inhibitors (TNFi). Often, both treatments are used in combination (33%), followed by combinations of NSAIDs and synthetic disease modifying antirheumatic drugs (sDMARDs) with 23% or TNFi alone (21%). In 2012, 10% of patients each received NSAID or sDMARD monotherapy. Methotrexate, sulfasalazine, glucocorticoids and analgaesics alone or in combination with other treatments were given to 10% of patients, respectively. Over the years, we have seen remarkable improvements in disease control and patient reported outcomes. These developments are consistent with enhanced functional status, increasing employment rates and decreasing sick leave, hospitalisation and work disability. CONCLUSIONS: In the German rheumatology secondary/tertiary care setting, routine care of patients with AS has changed tremendously during the past decade. Increasingly, more efficacious treatment options are reflected in improved clinical outcomes, quality of life and participation in the labour force.

Comparison of tocilizumab as monotherapy or with add-on disease-modifying antirheumatic drugs in patients with rheumatoid arthritis and inadequate responses to previous treatments: an open-label study close to clinical practice.

This was an exploratory analysis comparing the safety and efficacy of tocilizumab monotherapy with those of tocilizumab in combination with disease-modifying anti-rheumatic drugs (DMARDs). Data were from a single-arm, nonrandomized, open-label, 24-week study in patients with rheumatoid arthritis in which patients with inadequate responses to DMARDs or tumor necrosis factor-α inhibitors received tocilizumab 8 mg/kg intravenously every 4 weeks plus methotrexate/other DMARD(s) combination therapy. If they were intolerant of methotrexate/other DMARD, patients received tocilizumab monotherapy. Effectiveness endpoints included American College of Rheumatology (ACR) responses (ACR20/50/70/90) and disease activity score using 28 joints (DAS28). Of 1,681 patients, 239 received tocilizumab monotherapy, and 1,442 received combination therapy. Methotrexate was the most common DMARD (79%) used in combination therapy. The frequency of adverse events (AEs), serious AEs, and AEs leading to withdrawal were similar between tocilizumab monotherapy (82.4, 7.9, and 5.4%, respectively) and combination therapy (76.6, 7.8, and 5.1%, respectively). No differences in ACR20/50/70/90 responses were observed between treatment groups (66.9%/43.5%/23.8%/10.0% vs 66.9%/47.2%/26.8%/8.5%, respectively; p > 0.12 for all individual comparisons, including ACR50 propensity score analyses). The decrease in DAS28 was also similar between treatment groups (mean ± standard deviation: -3.41 ± 1.49 for tocilizumab monotherapy vs -3.43 ± 1.43 for combination therapy; p > 0.33 all analyses, including propensity score analyses). Tocilizumab had a comparable safety profile, and was similarly effective, when used as monotherapy or in combination with DMARDs in a broad population of patients with rheumatoid arthritis.

A new reversible and potent P2Y12 receptor antagonist (ACT-246475): tolerability, pharmacokinetics, and pharmacodynamics in a first-in-man trial.

BACKGROUND AND OBJECTIVES: ACT-246475 is a new reversible, selective, and potent antagonist of the platelet P2Y12 receptor. This study was a first-in-man trial investigating the tolerability, pharmacokinetics, and pharmacodynamics of single oral doses of ACT-246475 and its di-ester prodrug (ACT-281959) in healthy males. METHODS: The study had a double-blind, randomized, ascending single-dose design with an oral formulation F1 (i.e., ACT-281959 or placebo) (Part I) and an open-label, randomized, 3-period, crossover design comparing exploratory formulations of ACT-281959 (F2) 70 mg and ACT-246475 (dF) 50 mg to F1 70 mg (Part II). In Part I, doses up to 1,000 mg were tested in 40 healthy subjects. Nine healthy subjects were enrolled in Part II. Standard safety parameters, inhibition of platelet aggregation, and ACT-246475 plasma concentrations were measured. Non-compartmental pharmacokinetic analysis was performed. RESULTS: All doses and formulations were well tolerated. The most frequent adverse event was headache, whereas no events of bleeding or dyspnea were reported. In Part I, ACT-246475 area under the plasma concentration-time curve (AUC) increased dose-proportionally whereas maximum plasma concentration (C max) was less than dose-proportional. The highest C max [geometric mean (95 % CI)] at 1,000 mg was 13.8 (9.7, 19.5) pmol/mL at 4.5 h post-dose, terminal half-life (t ½) was ~10 h. ACT-246475 C max and AUC0-∞ ratios of geometric means (90 % CI) using F1 as reference, for F2 were 8.5 (5.42, 13.35) and 3.4 (2.40, 4.82), respectively, and for dF 2.2 (1.42, 3.49) and 1.5 (1.07, 2.16), respectively. Mean peak platelet inhibition was 31.0 % after F1 (1,000 mg) and 47.8 % after F2. CONCLUSIONS: Oral doses of ACT-281959 and ACT-246475 were well tolerated. Platelet inhibition correlated with ACT-246475 exposure. Exploratory formulations enhanced the bioavailability and antiplatelet effect of ACT-246475.

Low-field MRI versus ultrasound: which is more sensitive in detecting inflammation and bone damage in MCP and MTP joints in mild or moderate rheumatoid arthritis?

OBJECTIVES: The aim of the present paper is to determine if the ultrasound of hands and feet is comparable to the MRI of the dominant hand to detect erosive disease and inflammation in mild or moderate rheumatoid arthritis (RA). METHODS: Twenty-six patients (14 females; mean age, 48 years) with active mild or moderate RA (mean DAS28, 3.9; mean disease duration, 19 months) were examined clinically, by ultrasound and by gadolinium-enhanced low-field MRI at baseline, after 6 and 12 months (78 examinations). Radiographs from hands and forefeet were taken at baseline and after 12 months. MRI was performed at the clinically most active (dominant) hand or forefoot evaluating the MCP 1-5 or MTP 1-5 joints. Ultrasound examination additionally included all other 2nd, 5th MCP and 5th MTP joints. RESULTS: MRI and ultrasound detected erosive disease in 67 and 56 of 78 examinations, respectively (p<0.01); radiography only in 8 of 52 examinations (p<0.001). MRI and ultrasound were equally sensitive to detect synovitis (in 64 and 66 examinations). Synovial power Doppler signals were present in 38 ultrasound examinations. Bone marrow oedema was present in 37 MRI examinations. Ultrasound was more sensitive than MRI to detect tenosynovitis (in 30 vs. 15 examinations; p=0.001). CONCLUSIONS: MRI of the dominant hand and bilateral ultrasound of MCP and MTP joints are superior to x-ray to detect erosive disease in mild and moderate RA. MRI is slightly, but significantly more sensitive than ultrasound for erosive disease, while ultrasound is more sensitive to detect tenosynovitis. Ultrasound and MRI are comparably sensitive to detect synovitis.

SCHEMA-designed variants of human Arginase I and II reveal sequence elements important to stability and catalysis.

Arginases catalyze the divalent cation-dependent hydrolysis of L-arginine to urea and L-ornithine. There is significant interest in using arginase as a therapeutic antineogenic agent against L-arginine auxotrophic tumors and in enzyme replacement therapy for treating hyperargininemia. Both therapeutic applications require enzymes with sufficient stability under physiological conditions. To explore sequence elements that contribute to arginase stability we used SCHEMA-guided recombination to design a library of chimeric enzymes composed of sequence fragments from the two human isozymes Arginase I and II. We then developed a novel active learning algorithm that selects sequences from this library that are both highly informative and functional. Using high-throughput gene synthesis and our two-step active learning algorithm, we were able to rapidly create a small but highly informative set of seven enzymatically active chimeras that had an average variant distance of 40 mutations from the closest parent arginase. Within this set of sequences, linear regression was used to identify the sequence elements that contribute to the long-term stability of human arginase under physiological conditions. This approach revealed a striking correlation between the isoelectric point and the long-term stability of the enzyme to deactivation under physiological conditions.