Staphylococcus aureus mutants resistant to the feed-additive monensin show increased virulence and altered purine metabolism

Ionophores are antibacterial compounds that affect bacterial growth by changing intracellular concentrations of the essential cations, sodium and potassium. They are extensively used in animal husbandry to increase productivity and reduce infectious diseases, but our understanding of the potential for and effects of resistance development to ionophores is poorly known. Thus, given their widespread global usage, it is important to determine the potential negative consequences of ionophore use on human and animal health. In this study, we demonstrate that exposure to the ionophore monensin can select for resistant mutants in the human and animal pathogen Staphylococcus aureus, with a majority of the resistant mutants showing increased growth rates in vitro and/or in mice. Whole-genome sequencing and proteomic analysis of the resistant mutants show that the resistance phenotype is associated with de-repression of de novo purine synthesis, which could be achieved through mutations in different transcriptional regulators including mutations in the gene purR, the repressor of the purine de novo synthesis pathway. This study shows that mutants with reduced susceptibility to the ionophore monensin can be readily selected and highlights an unexplored link between ionophore resistance, purine metabolism, and fitness in pathogenic bacteria.IMPORTANCEThis study demonstrates a novel link between ionophore resistance, purine metabolism, and virulence/fitness in the key human and animal pathogen Staphylococcus aureus. The results show that mutants with reduced susceptibility to the commonly used ionophore monensin can be readily selected and that the reduced susceptibility observed is associated with an increased expression of the de novo purine synthesis pathway. This study increases our understanding of the impact of the use of animal feed additives on both human and veterinary medicine.

Progress and harmonization of gene editing to treat human diseases: Proceeding of COST Action CA21113 GenE-HumDi

The European Cooperation in Science and Technology (COST) is an intergovernmental organization dedicated to funding and coordinating scientific and technological research in Europe, fostering collaboration among researchers and institutions across countries. Recently, COST Action funded the "Genome Editing to treat Human Diseases" (GenE-HumDi) network, uniting various stakeholders such as pharmaceutical companies, academic institutions, regulatory agencies, biotech firms, and patient advocacy groups. GenE-HumDi's primary objective is to expedite the application of genome editing for therapeutic purposes in treating human diseases. To achieve this goal, GenE-HumDi is organized in several working groups, each focusing on specific aspects. These groups aim to enhance genome editing technologies, assess delivery systems, address safety concerns, promote clinical translation, and develop regulatory guidelines. The network seeks to establish standard procedures and guidelines for these areas to standardize scientific practices and facilitate knowledge sharing. Furthermore, GenE-HumDi aims to communicate its findings to the public in accessible yet rigorous language, emphasizing genome editing's potential to revolutionize the treatment of many human diseases. The inaugural GenE-HumDi meeting, held in Granada, Spain, in March 2023, featured presentations from experts in the field, discussing recent breakthroughs in delivery methods, safety measures, clinical translation, and regulatory aspects related to gene editing.

Polyether Ionophore Antibiotics Target Drug-Resistant Clinical Isolates, Persister Cells, and Biofilms

Polyether ionophores are complex natural products known to transport various cations across biological membranes. While several members of this family are used in agriculture (e.g., as anti-coccidiostats) and have potent antibacterial activity, they are not currently being pursued as antibiotics for human use. Polyether ionophores are typically grouped as having similar functions, despite the fact that they significantly differ in structure; for this reason, how their structure and activity are related remains unclear. To determine whether certain members of the family constitute particularly interesting springboards for in-depth investigations and future synthetic optimization, we conducted a systematic comparative study of eight different polyether ionophores for their potential as antibiotics. This includes clinical isolates from bloodstream infections and studies of the compounds' effects on bacterial biofilms and persister cells. We uncover distinct differences within the compound class and identify the compounds lasalocid, calcimycin, and nanchangmycin as having particularly interesting activity profiles for further development. IMPORTANCE Polyether ionophores are complex natural products used in agriculture as anti-coccidiostats in poultry and as growth promoters in cattle, although their precise mechanism is not understood. They are widely regarded as antimicrobials against Gram-positive bacteria and protozoa, but fear of toxicity has so far prevented their use in humans. We show that ionophores generally have very different effects on Staphylococcus aureus, both in standard assays and in more complex systems such as bacterial biofilms and persister cell populations. This will allow us to focus on the most interesting compounds for future in-depth investigations and synthetic optimizations.

An Endogenous Staphylococcus aureus CRISPR-Cas System Limits Phage Proliferation and Is Efficiently Excised from the Genome as Part of the SCCmec Cassette

CRISPR-Cas is an adaptive immune system that allows bacteria to inactivate mobile genetic elements. Approximately 50% of bacteria harbor CRISPR-Cas; however, in the human pathogen Staphylococcus aureus, CRISPR-Cas loci are less common and often studied in heterologous systems. We analyzed the prevalence of CRISPR-Cas in genomes of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in Denmark. Only 2.9% of the strains carried CRISPR-Cas systems, but for strains of sequence type ST630, over half were positive. All CRISPR-Cas loci were type III-A and located within the staphylococcal cassette chromosome mec (SCCmec) type V(5C2&5), conferring β-lactam resistance. Curiously, only 23 different CRISPR spacers were identified in 69 CRISPR-Cas positive strains, and almost identical SCCmec cassettes, CRISPR arrays, and cas genes are present in staphylococcal species other than S. aureus, suggesting that these were transferred horizontally. For the ST630 strain 110900, we demonstrate that the SCCmec cassette containing CRISPR-Cas is excised from the chromosome at high frequency. However, the cassette was not transferable under the conditions investigated. One of the CRISPR spacers targets a late gene in the lytic bacteriophage phiIPLA-RODI, and we show that the system protects against phage infection by reducing phage burst size. However, CRISPR-Cas can be overloaded or circumvented by CRISPR escape mutants. Our results imply that the endogenous type III-A CRISPR-Cas system in S. aureus is active against targeted phages, albeit with low efficacy. This suggests that native S. aureus CRISPR-Cas offers only partial immunity and in nature may work in tandem with other defense systems. IMPORTANCE CRISPR-Cas is an adaptive immune system protecting bacteria and archaea against mobile genetic elements such as phages. In strains of Staphylococcus aureus, CRISPR-Cas is rare, but when present, it is located within the SCCmec element, which encodes resistance to methicillin and other β-lactam antibiotics. We show that the element is excisable, suggesting that the CRISPR-Cas locus is transferable. In support of this, we found almost identical CRISPR-Cas-carrying SCCmec elements in different species of non-S. aureus staphylococci, indicating that the system is mobile but only rarely acquires new spacers in S. aureus. Additionally, we show that in its endogenous form, the S. aureus CRISPR-Cas is active but inefficient against lytic phages that can overload the system or form escape mutants. Thus, we propose that CRISPR-Cas in S. aureus offers only partial immunity in native systems and so may work with other defense systems to prevent phage-mediated killing.

Risk assessment of the asthma-induction potential of substances in spray products for car cabin detailing - based on EU's Chemical Agents Directive, using harmonised classifications and quantitative structure-activity relationship (QSAR)

Exposure to spray-formulated products for car cabin detailing is a potential risk for asthma induction. With a focus on the asthma-related endpoints sensitisation and irritation of the lungs, we performed an occupational risk assessment based on requirements in the EU Chemical Agents Directive. We identified 71 such spray products available in Denmark. We identified ingredient substances in safety data sheets and screened for harmonised classifications of respiratory sensitisation and airway irritation. For respiratory sensitisation, we also applied quantitative structure-activity relationship (QSAR). We modelled the exposure during 15 min of work inside a car cabin, and determined the risk ratio of the products by further applying occupational exposure limits - mainly derived no-effect levels (DNELs) from the European Chemicals Agency (ECHA) set on respiratory irritation. Four substances had a harmonised classification for respiratory irritation (bronopol, 2-phenoxyethanol, 2-methoxypropanol, and butan-1-ol). Seven substances were positive in the QSAR model for respiratory sensitisation (monoethanolamine, bronopol, glycerol, methyl salicylate, benzoic acid, ammonium benzoate, and sodium benzoate). Two vinyl treatment products had a risk ratio > 1 based on the level of sodium benzoate and its DNEL set on respiratory irritation. Two products had risk ratios of 0.69 and 0.73, respectively, based on 2-methyl-2 H-isothiazol-3-one and its acute DNEL set on respiratory irritation. In conclusion, 10 substances that may pose a risk for asthma induction were identified in the products. Two of the 71 products had a risk ratio > 1, meaning they may pose an asthma-induction risk in the modelled exposure scenario and using respiratory irritation DNELs from ECHA.

Functional Characterization of Type III-A CRISPR-Cas in a Clinical Human Methicillin-R Staphylococcus aureus Strain

CRISPR with its cas genes is an adaptive immune system that protects prokaryotes against foreign genetic elements. The type III-A CRISPR-Cas system is rarely found in Staphylococcus aureus, and little is known about its function in S. aureus. Here, we describe the genome characteristics of the clinical methicillin-resistant S. aureus (MRSA) strain TZ0912, carrying a type III-A CRISPR-Cas system. Phylogenetic analysis of 35 reported CRISPR-Cas-positive S. aureus strains revealed that the CRISPR-Cas system is prevalent in CC8 clones (10/35) and is located in the staphylococcal cassette chromosome mec (SCCmec) V, which confers methicillin resistance. Plasmid transformation and phage infection assays reveal that the type III-A CRISPR-Cas system protects TZ0912 against foreign DNA with sequence homology to the spacers located in the CRISPR array. We observed that the CRISPR-Cas immune system could effectively protect MRSA against phage attacks in both liquid culture and solid medium. In accordance with previous reports, using RNA-seq analysis and plasmid transformation assays, we find that the crRNAs close to the leading sequence of the CRISPR array are more highly expressed and are more effective at directing plasmid elimination compared to the distant spacers. This study established a model for evaluating the efficiency of naive CRISPR-Cas system in MRSA against phage, which could contribute to future research on the function of CRISPR-Cas in clinical MRSA isolates and improve phage therapy against MRSA infections.

The Novel Membrane-Associated Auxiliary Factors AuxA and AuxB Modulate β-lactam Resistance in MRSA by stabilizing Lipoteichoic Acids

A major determinant of β-lactam resistance in methicillin-resistant Staphylococcus aureus (MRSA) is the drug insensitive transpeptidase, PBP2a, encoded by mecA. Full expression of the resistance phenotype requires auxiliary factors. Two such factors, auxiliary factor A (auxA, SAUSA300_0980) and B (auxB, SAUSA300_1003), were identified in a screen against mutants with increased susceptibility to β-lactams in the MRSA strain, JE2. auxA and auxB encode transmembrane proteins, with AuxA predicted to be a transporter. Inactivation of auxA or auxB enhanced β-lactam susceptibility in community-, hospital- and livestock-associated MRSA strains without affecting PBP2a expression, peptidoglycan cross-linking or wall teichoic acid synthesis. Both mutants displayed increased susceptibility to inhibitors of lipoteichoic acid (LTA) synthesis and alanylation pathways and released LTA even in the absence of β-lactams. The β-lactam susceptibility of the aux mutants was suppressed by mutations inactivating gdpP, which was previously found to allow growth of mutants lacking the lipoteichoic synthase enzyme, LtaS. Using the Galleria mellonella infection model, enhanced survival of larvae inoculated with either auxA or auxB mutants was observed compared with the wild-type strain following treatment with amoxicillin. These results indicate that AuxA and AuxB are central for LTA stability and potential inhibitors can be tools to re-sensitize MRSA strains to β-lactams and combat MRSA infections.

Carcinoembryonic Antigen (CEA)-Specific 4-1BB-Costimulation Induced by CEA-Targeted 4-1BB-Agonistic Trimerbodies

4-1BB (CD137) is an inducible costimulatory receptor that promotes expansion and survival of activated T cells; and IgG-based 4-1BB-agonistic monoclonal antibodies exhibited potent antitumor activity in clinical trials. However, the clinical development of those antibodies is restricted by major off-tumor toxicities associated with FcγR interactions. We have recently generated an EGFR-targeted 4-1BB-agonistic trimerbody that demonstrated strong antitumor activity and did not induce systemic inflammatory cytokine secretion and hepatotoxicity associated with first-generation 4-1BB agonists. Here, we generate a bispecific 4-1BB-agonistic trimerbody targeting the carcinoembryonic antigen (CEA) that is highly expressed in cancers of diverse origins. The CEA-targeted anti-4-1BB-agonistic trimerbody consists of three 4-1BB-specific single-chain fragment variable antibodies and three anti-CEA single-domain antibodies positioned around a murine collagen XVIII-derived homotrimerization domain. The trimerbody was produced as a homogenous, non-aggregating, soluble protein purifiable by standard affinity chromatographic methods. The purified trimerbody was found to be trimeric in solution, very efficient at recognizing 4-1BB and CEA, and potently costimulating T cells in vitro in the presence of CEA. Therefore, trimerbody-based tumor-targeted 4-1BB costimulation is a broadly applicable and clinically feasible approach to enhance the costimulatory environment of disseminated tumor lesions.

Bispecific light T-cell engagers for gene-based immunotherapy of epidermal growth factor receptor (EGFR)-positive malignancies

The recruitment of T-cells by bispecific antibodies secreted from adoptively transferred, gene-modified autologous cells has shown satisfactory results in preclinical cancer models. Even so, the approach's translation into the clinic will require incremental improvements to its efficacy and reduction of its toxicity. Here, we characterized a tandem T-cell recruiting bispecific antibody intended to benefit gene-based immunotherapy approaches, which we call the light T-cell engager (LiTE), consisting of an EGFR-specific single-domain VHH antibody fused to a CD3-specific scFv. We generated two LiTEs with the anti-EGFR VHH and the anti-CD3 scFv arranged in both possible orders. Both constructs were well expressed in mammalian cells as highly homogenous monomers in solution with molecular weights of 43 and 41 kDa, respectively. In situ secreted LiTEs bound the cognate antigens of both parental antibodies and triggered the specific cytolysis of EGFR-expressing cancer cells without inducing T-cell activation and cytotoxicity spontaneously or against EGFR-negative cells. Light T-cell engagers are, therefore, suitable for future applications in gene-based immunotherapy approaches.

ATTACK, a novel bispecific T cell-recruiting antibody with trivalent EGFR binding and monovalent CD3 binding for cancer immunotherapy

The redirection of T cell activity using bispecific antibodies is one of the most promising cancer immunotherapy approaches currently in development, but it is limited by cytokine storm-related toxicities, as well as the pharmacokinetics and tumor-penetrating capabilities of current bispecific antibody formats. Here, we have engineered the ATTACK (Asymmetric Tandem Trimerbody for T cell Activation and Cancer Killing), a novel T cell-recruiting bispecific antibody which combines three EGFR-binding single-domain antibodies (V_HH; clone EgA1) with a single CD3-binding single-chain variable fragment (scFv; clone OKT3) in an intermediate molecular weight package. The two specificities are oriented in opposite directions in order to simultaneously engage cancer cells and T cell effectors, and thereby promote immunological synapse formation. EgA1 ATTACK was expressed as a homogenous, non-aggregating, soluble protein by mammalian cells and demonstrated an enhanced binding to EGFR, but not CD3, when compared to the previously characterized tandem bispecific antibody which has one EgA1 V_HH and one OKT3 scFv per molecule. EgA1 ATTACK induced synapse formation and early signaling pathways downstream of TCR engagement at lower concentrations than the tandem V_HH-scFv bispecific antibody. Furthermore, it demonstrated extremely potent, dose-dependent cytotoxicity when retargeting human T cells towards EGFR-expressing cells, with an efficacy over 15-fold higher than that of the tandem V_HH-scFv bispecific antibody. These results suggest that the ATTACK is an ideal format for the development of the next-generation of T cell-redirecting bispecific antibodies.

Anti-CCP and RF IgM: predictors of impaired endothelial function in rheumatoid arthritis patients

OBJECTIVE

To determine whether the presence of anti-cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor immunoglobulin M (RF IgM) is associated with endothelial dysfunction in patients with rheumatoid arthritis (RA).

METHODS

We studied the presence of anti-CCP antibodies and RF IgM and endothelial function in terms of the reactive hyperaemic index (RHI) in 53 consecutive RA patients. Endothelial function was measured by using a finger plethysmograph.

RESULTS

RHI was significantly lower in anti-CCP-positive RA patients (n = 33, RHI = 1.78, SD = 0.30) than in anti-CCP-negative RA patients (n = 20, RHI = 2.19, SD = 0.59; p = 0.008). A similar result was found in RF IgM-positive patients (n  =  34, RHI = 1.77, SD = 0.30) vs. RF IgM-negative patients (n = 19, RHI = 2.23, SD = 0.58; p = 0.003). There were no significant differences between the groups regarding age, gender, traditional cardiovascular risk markers, Disease Activity Score using 28 joint counts (DAS28), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), extra-articular manifestations (EAMs), use of glucocorticosteroids, statins, angiotensin-converting enzyme (ACE) inhibitors, and non-steroidal anti-inflammatory drugs (NSAIDs).

CONCLUSION

The presence of anti-CCP antibodies and RF IgM was related to impaired endothelial function independent of other cardiovascular risk factors in RA patients. Thus, these autoantibodies might reflect an early reversible stage of the atherosclerotic process, and may indicate increased risk of cardiovascular disease (CVD). Further studies are needed to explore whether anti-CCP antibodies and RF IgM may act directly or indirectly to cause endothelial dysfunction, or merely reflect endothelial dysfunction in RA patients.

Treatment of fibromyalgia at the Maharishi Ayurveda Health Centre in Norway. A six-month follow-up study

BACKGROUND

Treatments offered at the Maharishi Ayurveda Health Centre in Norway are based on Maharishi Vedic medicine, which is also known as Maharishi Ayurveda. It is a consciousness based revival of the ancient Ayurvedic medicine tradition in India and is established by Maharishi Mahesh Yogi, the founder of the Transcendental Meditation (TM) technique.

OBJECTIVE

To conduct a pilot study of the effect of the treatment program at the Health Centre on fibromyalgia patients.

METHODS

Thirty-one women with diagnosed fibromyalgia received an individually designed Maharishi Vedic physiological purification therapy. All subjects received personal advice on diet based on Ayurvedic principles, including a novel approach to food into-lerance, and daily routines. In addition they were offered instruction in TM (for stress and pain management and personal development) (four subjects started), and recommended Ayurvedic herbal food products for home treatment.

MAIN OUTCOME MEASURES

A modified Fibromyalgia Impact Questionnaire included a visual analogue scale for each of the seven outcomes: working ability, generalised pain, tiredness, stiffness, tiredness on arising, anxiety and depression. Pre-treatment scores were compared with scores at six-month follow-up for levels of statistical significance.

RESULTS

Twenty-eight subjects (90%) completed the follow-up. The outcome measures were reduced by 25 to 46% by the study's endpoint: working ability (p<0.002), pain (p<0.001), tiredness (p<0.001), morning tiredness (p<0.001), stiffness (p<0.005), anxiety (p<0.136), and depression (p<0.001). A group of five excellent responders including all four participants who started to practise TM, had almost no symptoms by the endpoint. Compared to the non-meditating control group the TM-subgroup showed statistically significant improvements for all outcome measures except depression.

CONCLUSIONS

In this pilot study fibromyalgia patients undergoing treatment at Maharishi Ayurveda Health Centre in Norway showed significant improvements six months post treatment. Because fibromyalgia is considered a treatment-resistant condition, these encouraging results warrant further research.

Postpartum onset of rheumatoid arthritis and other chronic arthritides: results from a patient register linked to a medical birth registry

Background:

It is known that onset of rheumatoid arthritis (RA) is increased post partum.

Objective:

To compare incidence rates between RA and other chronic arthritides (OCA) 0–24 months after delivery, and to compare the incidence rates within each group 0–24 versus 25–48 months post partum.

Methods:

Premenopausal women from a Norwegian patient register were linked with the Medical Birth Registry of Norway to study the interval between delivery and time of diagnosis. Cox regression analysis with adjustments for age at delivery and birth order was applied to compare proportions of incident cases of RA and OCA with onset 0–24 months post partum. Poisson regression analysis with adjustment for the population at risk was applied to estimate the incidence rate ratio (IRR) 0–24 versus 25–48 months post partum.

Results:

Of 183 RA and 110 patients with OCA diagnosed after delivery, 69 (37.7%) had RA and 31 (28.2%) OCA during the first 24 months post partum (p = 0.09). The IRR (95% CI) for diagnosis during 0–24 months versus 25–48 months was 1.73 (1.11 to 2.70) (p = 0.01) for RA, 1.05 (0.59 to 1.84) (p = 0.86) for OCA. The IRR was 2.23 (1.06 to 4.70) and 1.87 (0.67 to 5.21), respectively, when only considering diagnoses after the first pregnancy. Clinical characteristics were similar within each diagnostic group.

Conclusion:

The proportions of incident cases with onset 0–24 months after delivery were not different between RA and OCA. A peak in incidence during 0–24 months was seen in the RA group, both when considering all pregnancies and only the first pregnancy.

Comparison of work disability and health-related quality of life between males and females with rheumatoid arthritis below the age of 45 years

OBJECTIVES

To compare work disability (WD) and health status between males and females with rheumatoid arthritis (RA) in the age group 18-45 years, and to compare health status between patients with and without WD within each gender, and finally to identify factors independently associated with WD in this age group.

METHODS

A cross-sectional study of RA patients at the time starting with disease-modifying antirheumatic drug (DMARD) therapy and/or biological treatment. Patients receiving a permanent, national WD pension corresponding to >or= 50% were defined as work disabled. We examined gender differences with regard to disease characteristics, health status and WD. The Mann-Whitney U-test and Pearson's chi(2)-test were applied for group comparisons. Multiple logistic regression analyses with adjustments for duration of education, disease duration, age, erosive disease, disability score [using the Modified Health Assessment Questionnaire (MHAQ)], Disease Activity Score-28 (DAS-28), the Short Form Health Survey (SF-36) mental health score and gender were used to identify variables associated with WD.

RESULTS

Out of 474 (372 females) patients, the number (%) of work-disabled females/males was 91 (24.7)/8 (8.1) (p<0.001). WD was associated with worse health status in both genders. The odds ratio (95% confidence interval) [OR (95% CI)] for WD in females vs. males was 4.84 (1.85-12.65) in the multivariate analyses. Other factors independently associated with WD were worse mental health, disease duration and low level of education.

CONCLUSION

Females with RA had a fourfold increased risk of WD compared to men. Low level of education, disease duration and worse mental health were also independently associated with WD.

Work disability and health-related quality of life in males and females with psoriatic arthritis

OBJECTIVES

To compare health status, demographic variables and work disability (WD) between males and females with psoriatic arthritis (PsA) in the 18-45 age group, and further to compare health status between those with and without WD for each gender and to identify variables associated with WD.

METHODS

A cross-sectional study was carried out of patients with PsA with peripheral arthritis at the time at which they started disease-modifying antirheumatic drug therapy (DMARD) and/or biological treatment. Patients receiving a permanent national WD pension corresponding to >or=50% were defined as work disabled. Gender differences were examined with regard to health status, demographic variables and WD. Mann-Whitney U test and Pearson chi(2) were applied for group comparisons between males and females and work disabled versus not work disabled for each gender. Multiple logistic regression analyses with adjustments for duration of education, disease duration, age, erosive disease, disability score (Modified Health Assessment Questionnaire; MHAQ), the short form-36 (SF-36) mental health score, and gender were used to identify variables associated with WD.

RESULTS

Out of 271 (102 females) patients, the number (%) of work-disabled females/males was 33 (32.7%)/29 (17.4%) (p = 0.004). Work-disabled patients had generally worse health status than non-work-disabled patients, and these differences were generally more pronounced in males than in females. In the multiple logistic regression model, low educational level, increasing disability score (MHAQ), presence of erosive disease, female gender and disease duration were independently associated with WD.

CONCLUSIONS

WD in patients with PsA below 45 years of age was independently associated with educational level, disability score, erosive disease, female gender and disease duration.

Efficacy and safety of a novel synergistic drug candidate, CRx-102, in hand osteoarthritis

OBJECTIVE

The novel synergistic drug candidate CRx-102 comprises dipyridamole and low dose prednisolone and is in clinical development for the treatment of immunoinflammatory diseases. The purpose of this clinical study was to examine the efficacy and safety of CRx-102 in patients with hand osteoarthritis (HOA).

METHODS

The study was conducted as a blinded, randomised, placebo-controlled trial at four centres in Norway. Eligibility criteria included being of age 30-70 years, at least one swollen and tender joint, a Kellgren-Lawrence (K-L) score of 2 or higher on radiographs, and a score of at least 30 mm pain on the Australian/Canadian Osteoarthritis Hand Index (AUSCAN) visual analogue pain scale (VAS). The primary endpoint was a reduction in pain from baseline to day 42 on the AUSCAN pain subscale. Two-sided p values for the differences in least squares (LS) means adjusted for baseline are presented.

RESULTS

The mean age of the 83 patients with HOA was 60 years and 93% were females. CRx-102 was statistically superior to placebo at 42 days for changes in AUSCAN pain (LS mean -14.2 vs -4.0) and for clinically relevant secondary endpoints (joint pain VAS (-18.6 vs -6.3), patient global VAS (-15.9 vs -4.2)) in the intention to treat population. The most frequently reported adverse event during the study was headache (52% in CRx-102 vs 15% in the placebo group).

CONCLUSIONS

The novel synergistic drug candidate CRx-102 demonstrated efficacy by statistically reducing pain compared to placebo in HOA and was generally well tolerated.

The comparative effectiveness of anti-TNF therapy and methotrexate in patients with psoriatic arthritis: 6 month results from a longitudinal, observational, multicentre study

OBJECTIVES

To compare the response to treatment with tumour necrosis factor (TNF) inhibitors and methotrexate (MTX) monotherapy in patients with psoriatic arthritis (PsA) within a real-life clinical setting.

METHODS

We analysed data from an ongoing longitudinal, observational multicentre study in Norway. Our data comprised 526 cases of patients with PsA who received either anti-TNF treatment (n = 146) or MTX monotherapy (n = 380) and were followed for at least 6 months with measures of disease activity, health status and utility scores. A propensity score was computed to adjust for channelling bias. The changes in measures of disease activity and health-related quality of life from baseline to 3- and 6-month follow-up were compared between the groups with adjustments for the baseline value of the dependent variable and the propensity score (analyses of covariance (ANCOVA)).

RESULTS

The groups were significantly different at baseline with respect to demographic and disease activity measures. The variables included in the propensity score were age, sex, number of previous disease modifying anti-rheumatic drugs (DMARDs), presence of erosive disease, treatment centre and investigator's global assessment. The adjusted changes at 6 months were significantly larger in the anti-TNF group for ESR, DAS-28, M-HAQ, patient's assessments of pain, fatigue and global disease activity on a visual analogue scale (VAS) and 4 out of 8 SF-36 dimensions.

CONCLUSIONS

Clinical improvement was superior with TNF inhibitors compared to MTX monotherapy in patients with PsA, when assessed in this setting of daily clinical practice.

Adalimumab and methotrexate is more effective than adalimumab alone in patients with established rheumatoid arthritis: results from a 6-month longitudinal, observational, multicentre study

OBJECTIVES

To compare the effectiveness of adalimumab monotherapy and adalimumab and methotrexate (MTX) combination therapy in patients with established rheumatoid arthritis.

METHODS

Data from an ongoing longitudinal observational study in Norway were used to compare response to treatment with two different adalimumab regimens (monotherapy, n = 84; combination with MTX, n = 99). Patients were assessed with measures of disease activity, health status and utility scores. Within-group changes were analysed from baseline to follow-up at 3 and 6 months and the changes were compared between groups after adjustment for the propensity score. The groups were also compared for the proportions of patients achieving European League Against Rheumatism (EULAR) good response, Disease Activity Score (DAS)28 remission and treatment terminations.

RESULTS

The improvement from baseline was significant for all measures in the adalimumab and MTX group, but only for DAS28, joint counts, two Short-form Health Survey with 36 questions (SF-36) dimensions and patient's and investigator's global assessment in the monotherapy group. All between-group differences were numerically in favour of combination therapy and significant for C reactive protein, joint counts, DAS28, Modified Health Assessment Questionnaire, investigator's global assessment, four SF-36 dimensions and Short Form 6D at 6 months. More patients in the combination therapy group reached EULAR good response (p<0.001) and remission (p = 0.07). At 6 months, 80.8% of the patients in the combination therapy group and 59.5% in the monotherapy group remained on treatment (p = 0.002). More withdrawals in the monotherapy group were due to adverse events.

CONCLUSIONS

Our results were consistent across several categories of end points and suggest that adalimumab combined with MTX is effective in patients with rheumatoid arthritis treated in daily clinical practice and is superior to adalimumab monotherapy.

A Norwegian DMARD register: prescriptions of DMARDs and biological agents to patients with inflammatory rheumatic diseases

Information concerning the effectiveness of drug therapy cannot be obtained only from randomized controlled clinical trials, due to limitations such as a short time frame and narrow inclusion and exclusion criteria. Therefore, complementary longitudinal observational studies performed in a real life setting are required. NOR-DMARD, a Norwegian 5-center register, was established in December 2000. All DMARD prescriptions to patients with inflammatory arthropathies are included, and patients are followed longitudinally with a variety of assessments. As of 2005, 4683 DMARD regimens have been included. Methotrexate is the most commonly used DMARD in rheumatoid arthritis and psoriatic arthritis. The proportions of patients who have received anti-TNF drugs in rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, juvenile arthritis and other diseases have been 22.5, 21.6, 53.8, 36.9 and 9.7%, respectively. The proportion of patients receiving anti-TNF drugs is considerably higher in 2004 than earlier, and criteria for prescribing anti-TNF drugs appear to be trending toward patients with less severe and active disease. Confounding by indication or channeling bias represents a challenge for the group comparisons of longitudinal effectiveness data, but can be addressed by modern statistical techniques. The NOR-DMARD register may in the future provide comparative real life effectiveness data that may also be used in cost-effectiveness analyses.

[Myalgia and high sedimentation rate in adults]

The polymyalgic syndrome may be the presenting clinical feature for several diseases such as polymyalgia rheumatica, temporal arteritis, malignancy, rheumatoid arthritis, virus infections, connective tissue diseases, and myositis. In this review we present the various diagnostic options seen from a rheumatological point of view, with emphasis on polymyalgia rheumatica, temporal arteritis and the paraneoplastic syndrome. We are of the opinion that polymyalgia rheumatica is overdiagnosed in general practice, and steroid treatment may delay diagnosis and treatment of other differential diagnosis presenting as the polymyalgic syndrome. Several recently published Norwegian epidemiological studies offer new information on various aspects of the polymyalgic syndrome, which will be discussed.

Hypovitaminosis D myopathy without biochemical signs of osteomalacic bone involvement

The aims of this study were to investigate myopathy in relation to vitamin D status, and to study the muscular effects of vitamin D treatment on vitamin D-deficient individuals. Further, hypovitaminosis D myopathy was investigated in relation to alkaline phosphatase (ALP), the most commonly used marker for hypovitaminosis D osteopathy. Eight patients with osteomalacia had an isokinetic dynamometer test of all major muscle groups before and after 3 months of vitamin D treatment. The most pronounced improvements in muscle power were seen in the weight-bearing antigravity muscles of the lower limbs. A cross-sectional study was performed among 55 vitamin D-deficient veiled Arab women living in Denmark and 22 Danish controls. An isometric dynamometer model was used for determination of quadriceps muscle power. Both maximal voluntary contraction (MVC) and electrically stimulated values (single twitch, maximal production rate (MPR), and maximal relaxation rate (MRR)) were determined. The women underwent high-dose vitamin D treatment and were retested after 3 and 6 months. Prior to vitamin D treatment all parameters of muscle function in the group of vitamin D-deficient Arab women were significantly reduced compared with Danish controls. MVC: 259.4 +/- 11.0 N (Newton) versus 392.6 +/- 11. 4 N (P < 10(-6)), single twitch: 47.0 +/- 1.8 N versus 74.6 +/- 2.2 N (P < 10(-5)), MPR 8.9 +/- 0.3 N/10 ms versus 14.3 +/- 0.4 N/10 ms (P < 10(-6)), MRR 4.5 +/- 0.2 N/10 ms versus 6.2 +/- 0.2 N/10 ms (P < 10(-6)). Muscle function was affected to a similar degree in women with and without bone involvement (as indicated by elevated ALP). After 3 months of vitamin D treatment all muscle-related parameters improved significantly. After 6 months only MVC was reduced compared with Danish controls (320.7 +/- 14.3 N (P < 0.02)), whereas all other measurements were normalized. Hypovitaminosis D myopathy is a prominent symptom of vitamin D deficiency, and severely impaired muscle function may be present even before biochemical signs of bone disease develop. Full normalization of hypovitaminosis D myopathy demands high-dose vitamin D treatment for 6 months or more. Our findings indicate that serum levels of ALP cannot be used in the screening for hypovitaminosis D myopathy. Assessment of s-25OHD is the only reliable test.

Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited

OBJECTIVES

Sunlight exposure of the skin is known to be the most important source of vitamin D. The aims of this study were: (i) to estimate vitamin D status amongst sunlight-deprived individuals (veiled Arab women, veiled ethnic Danish Moslem women and Danish controls); and (ii) through food intake analysis to estimate the oral intake of vitamin D necessary to keep a normal vitamin D status in sunlight-deprived individuals.

DESIGN

Cross-sectional study amongst randomly selected Moslem women of Arab origin living in Denmark. Age-matched Danish women were included as controls. To control for racial differences, a group of veiled ethnic Danish Moslem women (all Caucasians) was included.

SETTING

Primary Health Care Centre, City Vest and Department of Endocrinology and Metabolism C, University Hospital of Aarhus, Aarhus Amtssygehus, Aarhus, Denmark.

SUBJECTS

Sixty-nine Arab women (60 veiled, nine non-veiled) and 44 age-matched Danish controls were randomly selected amongst patients contacting the primary health care centre for reasons other than vitamin D deficiency. Ten ethnic Danish Moslem women were included through a direct contact with their community.

MAIN OUTCOME MEASURES

Serum levels of 25-hydroxyvitamin D were used as estimates of vitamin D status. Intact parathyroid hormone (PTH) was used to control for secondary hyperparathyroidism. Alkaline phosphatase and bone-specific alkaline phosphatase were used as markers for osteomalacic bone involvement. Oral intake of vitamin D and calcium were estimated through a historical food intake interview performed by a trained clinical dietician.

RESULTS

Veiled Arab women displayed extremely low values of 25-hydroxyvitamin D: 7.1 +/- 1.1 nmol L-1, compared with 17.5 +/- 2. 3 (P < 0.002) in ethnic Danish Moslems and 47.1 +/- 4.6 (P < 10-17) in Danish controls. PTH was increased amongst veiled Arab women: 15. 6 +/- 1.8 pmol L-1, compared with 5.7 +/- 1.4 in ethnic Danish Moslems and 2.7 +/- 0.3 (P < 10-6) in Danish controls. The vitamin D intake (including food supplementation) was very low amongst Arab women: 1.04 microg day-1, compared with 13.53 amongst ethnic Danish Moslems and 7.49 amongst Danish controls (P < 0.0005).

CONCLUSIONS

Severe vitamin D deficiency is prevalent amongst sunlight-deprived individuals living in Denmark. In veiled Arab women, vitamin D deficiency is the result of a combination of limitations in sunlight exposure and a low oral intake of vitamin D. The oral intake of vitamin D amongst veiled ethnic Danish Moslems was, however, very high, at 13.53 microgram (approximately 600 IU), but they were still vitamin D-deficient. Our results suggest that the daily oral intake of vitamin D in sunlight-deprived individuals should exceed 600 IU; most probably it should be 1000 IU day-1 to secure a normal level of 25-hydroxyvitamin D. This finding is in contrast with the commonly used RDA (recommended daily allowance) for adults in Europe: 200 IU day-1.