ObjectivesPatients with rheumatoid arthritis (RA) are at increased risk of lymphoma compared with the general population. There are concerns that tumour necrosis factor inhibitors (TNFi) may ...exacerbate this risk. However, since the excess risk of lymphoma in RA is related to the cumulative burden of inflammation, TNFi may conversely reduce the risk of lymphoma by decreasing the burden of inflammation. The aim of this study was to compare the risk of lymphoma in subjects with RA treated with TNFi with those treated with non-biological therapy.MethodsSubjects diagnosed by a rheumatologist with RA enrolled in the British Society for Rheumatology Rheumatoid Arthritis Register (BSRBR-RA), a prospective cohort study, were followed until first lymphoma, death or until 30 November 2013. Rates of lymphoma in the TNFi and non-biological-treated cohorts were compared using Cox regression.Results11 931 TNFi-treated patients were compared with 3367 biological-naive patients. 84 lymphomas (88 (95% CI 70 to 109) per 100 000 person-years) were reported in the TNFi cohort and 30 lymphomas (154 (95% CI 104 to 220)) in the biological-naive cohort. After adjusting for differences in baseline characteristics, there was no difference in the risk of lymphoma for the TNFi versus the biological-naive group: HR 1.00 (95% CI 0.56 to 1.80). No risk differences were observed for individual TNFi.ConclusionsIn medium-term follow-up, there is no evidence that tumour necrosis factor inhibition influences the risk of lymphoma over the background risk in subjects with RA.
ObjectivesPatients with rheumatoid arthritis (RA) are at increased risk of myocardial infarction (MI) compared with subjects without RA, with the increased risk driven potentially by inflammation. ...Tumour necrosis factor inhibitors (TNFi) may modulate the risk and severity of MI. We compared the risk and severity of MI in patients treated with TNFi with that in those receiving synthetic disease-modifying antirheumatic drugs (sDMARDs).MethodsThis analysis included patients with RA recruited from 2001 to 2009 to the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis starting TNFi (etanercept/infliximab/adalimumab) and a biologic-naïve comparator cohort receiving sDMARD. All patients were followed via physician and patient questionnaires and national death register linkage. Additionally, all patients were linked to the Myocardial Ischaemia National Audit Project, a national registry of hospitalisations for MI. Patients were censored at first verified MI, death, 90 days following TNFi discontinuation, last physician follow-up or 20 April 2010, whichever came first. The risk of first MI was compared between cohorts using COX regression, adjusted with propensity score deciles (PD). MI phenotype and severity were compared using descriptive statistics. 6-month mortality post MI was compared using logistic regression.Results252 verified first MIs were analysed: 58 in 3058 patients receiving sDMARD and 194 in 11 200 patients receiving TNFi (median follow-up per person 3.5 years and 5.3 years, respectively). The PD-adjusted HR of MI in TNFi referent to sDMARD was 0.61 (95% CI 0.41 to 0.89). No statistically significant differences in MI severity or mortality were observed between treatment groups.ConclusionsPatients with RA receiving TNFi had a decreased risk of MI compared with patients with RA receiving sDMARD therapy over the medium term. This might be attributed to a direct action of TNFi on the atherosclerotic process or better overall disease control.
Background Patients with rheumatoid arthritis (RA) have an increased risk of certain solid cancers, in particular lung cancer, compared to the general population. Treatment with tumour necrosis ...factor (TNF) inhibitors (TNFi) may further enhance this risk. Objectives To compare the risk of solid cancer in patients with RA treated with TNFi to that in patients treated with non-biologic (synthetic) disease modifying antirheumatic drugs (sDMARDs). Methods Patients with a physician diagnosis of RA enrolled in the British Society for Rheumatology Biologics Register, a national prospective cohort study established in 2001 to monitor the long-term safety of TNFi, were followed via record linkage with the national cancer registries until first solid cancer, death, for 5 years, or until 2011. Rates of solid cancers in 11 767 patients without prior cancer who received TNFi were compared to those in 3249 patients without prior cancer treated with sDMARDs. Results 427 solid cancers were reported in 52 549 patient-years follow-up for the TNFi group (81 (95% CI 74 to 89) per 10 000 patient-years) and 136 cancers were reported in 11 672 patient-years in the sDMARD cohort (117 (95% CI 98 to 138) per 10 000 patient-years). After adjusting for differences in baseline characteristics there was no difference in risk of solid cancer for TNFi compared to sDMARD treated patients: HR 0.83 (95% CI 0.64 to 1.07). There was no difference in the relative risk of cancer for any of the individual TNFi drugs. Conclusions The addition of TNFi to sDMARD does not alter the risk of cancer in RA patients selected for TNFi in the UK.
The molecular mechanisms of toxicity of chemically modified phosphorothioate antisense oligonucleotides (PS-ASOs) are not fully understood. Here, we report that toxic gapmer PS-ASOs containing ...modifications such as constrained ethyl (cEt), locked nucleic acid (LNA) and 2'-O-methoxyethyl (2'-MOE) bind many cellular proteins with high avidity, altering their function, localization and stability. We show that RNase H1-dependent delocalization of paraspeckle proteins to nucleoli is an early event in PS-ASO toxicity, followed by nucleolar stress, p53 activation and apoptotic cell death. Introduction of a single 2'-O-methyl (2'-OMe) modification at gap position 2 reduced protein-binding, substantially decreasing hepatotoxicity and improving the therapeutic index with minimal impairment of antisense activity. We validated the ability of this modification to generally mitigate PS-ASO toxicity with more than 300 sequences. Our findings will guide the design of PS-ASOs with optimal therapeutic profiles.
Triantennary N-acetyl galactosamine (GalNAc, GN3: ), a high-affinity ligand for the hepatocyte-specific asialoglycoprotein receptor (ASGPR), enhances the potency of second-generation gapmer antisense ...oligonucleotides (ASOs) 6-10-fold in mouse liver. When combined with next-generation ASO designs comprised of short S-cEt (S-2'-O-Et-2',4'-bridged nucleic acid) gapmer ASOs, ∼ 60-fold enhancement in potency relative to the parent MOE (2'-O-methoxyethyl RNA) ASO was observed. GN3: -conjugated ASOs showed high affinity for mouse ASGPR, which results in enhanced ASO delivery to hepatocytes versus non-parenchymal cells. After internalization into cells, the GN3: -ASO conjugate is metabolized to liberate the parent ASO in the liver. No metabolism of the GN3: -ASO conjugate was detected in plasma suggesting that GN3: acts as a hepatocyte targeting prodrug that is detached from the ASO by metabolism after internalization into the liver. GalNAc conjugation also enhanced potency and duration of the effect of two ASOs targeting human apolipoprotein C-III and human transthyretin (TTR) in transgenic mice. The unconjugated ASOs are currently in late stage clinical trials for the treatment of familial chylomicronemia and TTR-mediated polyneuropathy. The ability to translate these observations in humans offers the potential to improve therapeutic index, reduce cost of therapy and support a monthly dosing schedule for therapeutic suppression of gene expression in the liver using ASOs.
Abstract
Enhancing the functional uptake of antisense oligonucleotide (ASO) in the muscle will be beneficial for developing ASO therapeutics targeting genes expressed in the muscle. We hypothesized ...that improving albumin binding will facilitate traversal of ASO from the blood compartment to the interstitium of the muscle tissues to enhance ASO functional uptake. We synthesized structurally diverse saturated and unsaturated fatty acid conjugated ASOs with a range of hydrophobicity. The binding affinity of ASO fatty acid conjugates to plasma proteins improved with fatty acid chain length and highest binding affinity was observed with ASO conjugates containing fatty acid chain length from 16 to 22 carbons. The degree of unsaturation or conformation of double bond appears to have no influence on protein binding or activity of ASO fatty acid conjugates. Activity of fatty acid ASO conjugates correlated with the affinity to albumin and the tightest albumin binder exhibited the highest activity improvement in muscle. Palmitic acid conjugation increases ASO plasma Cmax and improved delivery of ASO to interstitial space of mouse muscle. Conjugation of palmitic acid improved potency of DMPK, Cav3, CD36 and Malat-1 ASOs (3- to 7-fold) in mouse muscle. Our approach provides a foundation for developing more effective therapeutic ASOs for muscle disorders.
Objective
Patients with rheumatoid arthritis (RA) are at an increased risk of ischemic stroke. Tumor necrosis factor inhibitors (TNFi) may influence risk and mortality after ischemic stroke by ...reducing inflammation. This study was undertaken to examine the association of TNFi with the risk of incident ischemic stroke and with 30‐day and 1‐year mortality after ischemic stroke.
Methods
Patients with RA starting therapy with TNFi and a biologics‐naive comparator group treated with synthetic disease‐modifying antirheumatic drugs (DMARDs) only were recruited to the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis from 2001 to 2009. Patients were followed up via clinical and patient questionnaires as well as the national death register. Incident strokes were classified as ischemic if brain imaging reports suggested ischemia or if ischemic stroke was reported as the underlying cause of death on a death certificate. Patients with a previous stroke were excluded. Risk of ischemic stroke was compared between patients receiving synthetic DMARDs only and those ever‐exposed to TNFi using a Cox proportional hazards regression model adjusted for potential confounders. Mortality after ischemic stroke was compared between synthetic DMARD–treated patients and TNFi‐treated patients using logistic regression, adjusted for age and sex.
Results
To April 2010, 127 verified incident ischemic strokes (21 in 3,271 synthetic DMARD–treated patients and 106 in 11,642 TNFi‐treated patients) occurred during 11,973 and 61,226 person‐years of observation, respectively (incidence rate 175 versus 173 per 100,000 person‐years). After adjustment for confounders, there was no association between ever‐exposure to TNFi and ischemic stroke (hazard ratio 0.99 95% confidence interval (95% CI) 0.54–1.81). Mortality 30 days or 1 year after ischemic stroke was not associated with concurrent TNFi exposure (odds ratio 0.18 95% CI 0.03–1.21 and 0.60 95% CI 0.16–2.28, respectively).
Conclusion
Exposure to TNFi does not appear to influence the occurrence of ischemic stroke in the medium term in patients with RA. The impact on mortality after ischemic stroke remains inconclusive.
IntroductionAssociations between cerebral small vessel disease (SVD) and inflammation have been largely examined using peripheral blood markers of inflammation, with few studies measuring ...inflammation within the brain. We investigated the cross-sectional relationship between SVD and in vivo neuroinflammation using 11CPK11195 positron emission tomography (PET) imaging.MethodsForty-two participants were recruited (according to NIA-AA guidelines, 14 healthy controls, 14 mild Alzheimer’s disease, 14 amyloid-positive mild cognitive impairment). Neuroinflammation was assessed using 11CPK11195 PET imaging, a marker of microglial activation. To quantify SVD, we assessed white matter hyperintensities (WMH), enlarged perivascular spaces, cerebral microbleeds and lacunes. Composite scores were calculated for global SVD burden, and SVD subtypes of hypertensive arteriopathy and cerebral amyloid angiopathy (CAA). General linear models examined associations between SVD and 11CPK11195, adjusting for sex, age, education, cognition, scan interval, and corrected for multiple comparisons via false discovery rate (FDR). Dominance analysis directly compared the relative importance of hypertensive arteriopathy and CAA scores as predictors of 11CPK11195.ResultsGlobal 11CPK11195 binding was associated with SVD markers, particularly in regions typical of hypertensive arteriopathy: deep microbleeds (β=0.63, F(1,35)=35.24, p<0.001), deep WMH (β=0.59, t=4.91, p<0.001). In dominance analysis, hypertensive arteriopathy score outperformed CAA in predicting 11CPK11195 binding globally and in 28 out of 37 regions of interest, especially the medial temporal lobe (β=0.66–0.76, t=3.90–5.58, FDR-corrected p (pFDR)=<0.001–0.002) and orbitofrontal cortex (β=0.51–0.57, t=3.53–4.30, pFDR=0.001–0.004).ConclusionMicroglial activation is associated with SVD, particularly with the hypertensive arteriopathy subtype of SVD. Although further research is needed to determine causality, our study suggests that targeting neuroinflammation might represent a novel therapeutic strategy for SVD.
Therapeutic oligonucleotides are often modified using the phosphorothioate (PS) backbone modification which enhances stability from nuclease mediated degradation. However, substituting oxygen in the ...phosphodiester backbone with sulfur introduce chirality into the backbone such that a full PS 16-mer oligonucleotide is comprised of 215 distinct stereoisomers. As a result, the role of PS chirality on the performance of antisense oligonucleotides (ASOs) has been a subject of debate for over two decades. We carried out a systematic analysis to determine if controlling PS chirality in the DNA gap region can enhance the potency and safety of gapmer ASOs modified with high-affinity constrained Ethyl (cEt) nucleotides in the flanks. As part of this effort, we examined the effect of systematically controlling PS chirality on RNase H1 cleavage patterns, protein mislocalization phenotypes, activity and toxicity in cells and in mice. We found that while controlling PS chirality can dramatically modulate interactions with RNase H1 as evidenced by changes in RNA cleavage patterns, these were insufficient to improve the overall therapeutic profile. We also found that controlling PS chirality of only two PS linkages in the DNA gap was sufficient to modulate RNase H1 cleavage patterns and combining these designs with simple modifications such as 2'-OMe to the DNA gap resulted in dramatic improvements in therapeutic index. However, we were unable to demonstrate improved potency relative to the stereorandom parent ASO or improved safety over the 2'-OMe gap-modified stereorandom parent ASO. Overall, our work shows that while controlling PS chirality can modulate RNase H1 cleavage patterns, ASO sequence and design are the primary drivers which determine the pharmacological and toxicological properties of gapmer ASOs.
Abstract
The PS modification enhances the nuclease stability and protein binding properties of gapmer antisense oligonucleotides (ASOs) and is one of very few modifications that support RNaseH1 ...activity. We evaluated the effect of introducing stereorandom and chiral mesyl-phosphoramidate (MsPA) linkages in the DNA gap and flanks of gapmer PS ASOs and characterized the effect of these linkages on RNA-binding, nuclease stability, protein binding, pro-inflammatory profile, antisense activity and toxicity in cells and in mice. We show that all PS linkages in a gapmer ASO can be replaced with MsPA without compromising chemical stability and RNA binding affinity but these designs reduced activity. However, replacing up to 5 PS in the gap with MsPA was well tolerated and replacing specific PS linkages at appropriate locations was able to greatly reduce both immune stimulation and cytotoxicity. The improved nuclease stability of MsPA over PS translated to significant improvement in the duration of ASO action in mice which was comparable to that of enhanced stabilized siRNA designs. Our work highlights the combination of PS and MsPA linkages as a next generation chemical platform for identifying ASO drugs with improved potency and therapeutic index, reduced pro-inflammatory effects and extended duration of effect.
Graphical Abstract
Graphical Abstract
Towards next generation antisense oligonucleotides: mesylphosphoramidate modification improves therapeutic index and duration of effect of gapmer antisense oligonucleotides.
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