Pharmacogenetics of therapies in rheumatoid arthritis: An update.

Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory arthritis. Despite many treatment advances, achieving remission or low-disease activity in RA remains challenging, often requiring trial and error approaches with numerous medications. Precision medicine, particularly pharmacogenomics, explores how genetic factors influence drug response in individual patients, and incorporates such factors to develop personalized treatments for individual patients. Genetic variations in drug-metabolizing enzymes, transporters, and targets may contribute to inter-individual differences in drug efficacy and toxicity. Advancements in molecular sequencing have allowed rapid identification of such variants, including single nucleotide polymorphisms (SNPs). This review highlights recent major findings in the pharmacogenetics of therapies in RA, focusing on key genes and SNPs to provide insights into current trends and developments in this field.

Pharmacogenetics of Drug Therapies in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disorder that can lead to severe joint damage and is often associated with a high morbidity and disability. Disease-modifying anti-rheumatic drugs (DMARDs) are the mainstay of treatment in RA. DMARDs not only relieve the clinical signs and symptoms of RA but also inhibit the radiographic progression of disease and reduce the effects of chronic systemic inflammation. Since the introduction of biologic DMARDs in the late 1990s, the therapeutic range of options for the management of RA has significantly expanded. However, patients' response to these agents is not uniform with considerable variability in both efficacy and toxicity. There are no reliable means of predicting an individual patient's response to a given DMARD prior to initiation of therapy. In this chapter, the current published literature on the pharmacogenetics of traditional DMARDS and the newer biologic DMARDs in RA is highlighted. Pharmacogenetics may help individualize drug therapy in patients with RA by providing reliable biomarkers to predict medication toxicity and efficacy.

Development and validation of lupus nephritis case definitions using United States veterans affairs electronic health records.

OBJECTIVE: International Classification of Diseases (ICD) codes are commonly used to identify patients with rare diseases in electronic health records (EHRs). However, misclassification is common, impacting the validity of study results. In this study, we compared the accuracies of several ICD-based case definitions of lupus nephritis (LN) in identifying United States veterans with LN. METHODS: Using the Department of Veterans Affairs (VA) EHR, we identified all veterans with ≥1 ICD-9 or 10 diagnostic codes for systemic lupus erythematosus (SLE) between October 1, 1999 and September 30, 2017. A cohort was randomly selected for diagnostic validation and 9 ICD-based LN case definitions were applied to this cohort. The diagnostic accuracy of each definition was assessed against gold standard criterion of biopsy-proven LN. RESULTS: 18,420 veterans had ≥1 ICD-9 or 10 diagnostic codes for SLE; 981 were randomly selected for diagnostic validation. 95 veterans (9.7%) had biopsy-proven LN. The case definitions had high specificity and NPV but variable sensitivity and PPV. The definition containing ≥2 ICD -9 codes for SLE and ≥2 nephritis indicators had the highest combination of sensitivity and specificity (87.4% and 94.6% respectively). ICD-10 code for LN had high specificity (99.8%) and PPV (93.9%). CONCLUSION: ICD-based case definitions of LN in the VA population have high specificity and NPV but variable sensitivity and PPV. Our results may help guide the design of future LN studies in VA cohorts. The choice of specific case definitions depends on the relative importance of different accuracy measures to individual studies.

A Potential Role for Stress-Induced Microbial Alterations in IgA-Associated Irritable Bowel Syndrome with Diarrhea.

Stress is a known trigger for flares of inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS); however, this process is not well understood. Here, we find that restraint stress in mice leads to signs of diarrhea, fecal dysbiosis, and a barrier defect via the opening of goblet-cell associated passages. Notably, stress increases host immunity to gut bacteria as assessed by immunoglobulin A (IgA)-bound gut bacteria. Stress-induced microbial changes are necessary and sufficient to elicit these effects. Moreover, similar to mice, many diarrhea-predominant IBS (IBS-D) patients from two cohorts display increased antibacterial immunity as assessed by IgA-bound fecal bacteria. This antibacterial IgA response in IBS-D correlates with somatic symptom severity and was distinct from healthy controls or IBD patients. These findings suggest that stress may play an important role in patients with IgA-associated IBS-D by disrupting the intestinal microbial community that alters gastrointestinal function and host immunity to commensal bacteria.

Successful use of rituximab for hydralazine-induced anti-neutrophil cytoplasmic antibodies-associated vasculitis.

Hydralazine is a commonly used anti-hypertensive medication. It can, however, contribute to the development of autoimmunity, in the form of drug-induced lupus and anti-neutrophil cytoplasmic antibodies-associated vasculitis. We report a 45-year-old patient with hypertension managed with hydralazine for four years who presented with rapidly progressive glomerulonephritis (RPGN), requiring hemodialysis, and diffuse alveolar hemorrhage (DAH), requiring mechanical ventilation, and extracorporeal membrane oxygenation. The patient's autoantibody profile was consistent with a drug-induced autoimmune process and renal histology revealed focal necrotizing crescentic GN. She was treated with high-dose steroids, plasma exchange and rituximab. DAH resolved and her renal function improved, allowing discontinuation of hemodialysis. This case reveals that rituximab can be successfully used in the setting of hydralazine-induced vasculitis, including critically ill patients with severe DAH and acute kidney injury from RPGN.

Tumor Necrosis Factor Inhibition and Head and Neck Cancer Recurrence and Death in Rheumatoid Arthritis.

The objective of this retrospective cohort study was to determine the effect of tumor necrosis factor inhibitor (TNFi) therapy on the risk of head and neck cancer (HNC) recurrence or HNC-attributable death in patients with rheumatoid arthritis (RA). RA patients with HNC were assembled from the US national Veterans' Affairs (VA) administrative databases, and diagnoses confirmed and data collected by electronic medical record review. The cohort was divided into those treated with non-biologic disease-modifying anti-rheumatic drugs (nbDMARDs) versus TNF inhibitors (TNFi) after a diagnosis of HNC. Likelihood of a composite endpoint of recurrence or HNC-attributable death was determined by Cox proportional hazards regression. Of 180 patients with RA and HNC, 31 were treated with TNFi and 149 with nbDMARDs after the diagnosis of HNC. Recurrence or HNC-attributable death occurred in 5/31 (16.1%) patients in the TNFi group and 44/149 (29.5%) patients in the nbDMARD group (p = 0.17); it occurred in 2/16 (13%) patients who received TNFi in the year prior to HNC diagnosis but not after. Overall stage at diagnosis (p = 0.03) and stage 4 HNC (HR 2.49 [CI 1.06-5.89]; p = 0.04) were risk factors for recurrence or HNC-attributable death; treatment with radiation or surgery was associated with a lower risk (HR 0.35 [CI 0.17-0.74]; p = 0.01 and HR 0.39 [CI 0.20-0.76]; p = 0.01 respectively). Treatment with TNFi was not a risk factor for recurrence or HNC-attributable death (HR 0.75; CI 0.31-1.85; p = 0.54). We conclude that treatment with TNFi may be safe in patients with RA and HNC, especially as the time interval between HNC treatment and non-recurrence increases. In this study, TNF inhibition was not associated with an increase in recurrence or HNC-attributable death.

Staphylococcus aureus sepsis in rheumatoid arthritis.

Patients with rheumatoid arthritis (RA) are at increased risk of infection. In this study, we determined the risk of and risk factors for Staphyococcus aureus (S. aureus) sepsis in RA. We assembled a retrospective nested case-control subset of RA patients with S. aureus sepsis from the Barnes-Jewish Hospital Medical Informatics database, confirmed the diagnoses, and collected data electronically and by chart review. We used multivariate logistic regression to identify independent risk factors for S. aureus sepsis, with risk expressed as odds ratios (ORs). We extracted data on the length of hospitalization and 30-day and 1-year mortality from the Medical Informatics database for all cases and controls. There were 48 confirmed S. aureus sepsis cases and 232 confirmed controls in the RA cohort. In multivariate analysis, indwelling central venous catheter (OR 15.97; 95 % CI 5.09-50.10; p < 0.01) and congestive heart failure (OR 2.89; 95 % CI 1.26-6.63; p = 0.01) were independently associated with risk of S. aureus sepsis, while treatment with disease-modifying anti-rheumatic drugs (DMARDs), both biologic and non-biologic, was not. S. aureus sepsis was associated with increased 30-day and 1-year mortality (OR 7.37; 95 % CI 2.86-19.0; p < 0.01 for 30-day and OR 5.24; 95 % CI 2.51-10.94; p < 0.01 for 1-year mortality) and longer hospitalization (p < 0.01). Treatment with biologic DMARDs was not associated with longer hospitalization (p = 0.89). Indwelling central venous catheters and congestive heart failure increased the risk of S. aureus sepsis in this observational cohort of patients with RA. Treatment with biologic and non-biologic DMARDs did not increase this risk.

Pharmacogenetics in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic inflammatory arthritis leading to severe joint damage and associated with high morbidity and mortality. Disease-modifying antirheumatic drugs (DMARDs) are the mainstay of treatment in RA. DMARDs not only relieve the clinical signs and symptoms of RA but also inhibit the radiographic progression of disease. In the last decade, a new class of disease-modifying medications, the biologic agents, has been added to the existing spectrum of DMARDs in RA. However, patients' response to these agents is not uniform with considerable variability in both efficacy and toxicity. There are no reliable means of predicting an individual patient's response to a given DMARD prior to initiation of therapy. In this chapter, the current published literature on the pharmacogenetics of traditional DMARDS and the newer biologic DMARDs in RA is highlighted. Pharmacogenetics may help individualize drug therapy in patients with RA in the near future.

Clinical trials in systemic lupus erythematosus: a status report on ongoing trials.

To describe the characteristics of trials in systemic lupus erythematous (SLE) listed in ClinicalTrials.gov such as study design, funding sources and aspects of the disease and drugs under investigation. We conducted a survey of ongoing clinical trials that were registered in the ClinicalTrials.gov website. We used the advanced search option and applied the following inclusion criteria, "SLE," "open studies," "interventional," and "adults 18 years or older." Of 97 eligible studies, 34.0 % were phase 3 or 4, 49.5 % were phase 1, 2 or 2/3 and in 16.5 %, we could not determine the study phase. Most trials were randomized (69.0 %) and 48.4 % were double blinded; 34 % of the trials were placebo controlled, 19.6 % had an active agent comparator and 46.4 % had no comparator. Universities and pharmaceutical industries were the primary sponsors for 45.3 and 39.1 % of the trials, respectively, and government agencies for 10.3 %. Multi-center trials based in the USA (US) accounted for 40.2 % of the trials, 46.4 % were outside of the US and 13.4 % were in the US as well as other countries. The most frequently used endpoint was drug efficacy (30.9 %) followed by disease severity indices (25.7 %), drug safety (14.4 %), remission rates and times to remission (7.2 %), and inflammatory markers and antibody titers (7.2 %). The majority of ongoing clinical trials in SLE are university or industry-funded, randomized phase 1, 2, or 2/3 trials, focused on drug efficacy. Federal funding for trials in SLE within and outside the US remains low.

Squamous cell carcinoma of the lip associated with adalimumab therapy for ankylosing spondylitis: a case report and review of TNF-α inhibitors and cutaneous carcinoma risk.

Adalimumab is an anti-tumor necrosis factor α (TNF-α) agent approved for the treatment of ankylosing spondylitis (AS); psoriatic arthritis; and moderate to severe cases of rheumatoid arthritis (RA), plaque psoriasis, Crohn disease, ulcerative colitis, and polyarticular juvenile idiopathic arthritis. Evidence suggests that anti-TNF-α agents may increase a patient's risk for some types of cancers, including cutaneous squamous cell carcinoma (SCC). Cutaneous nonmelanoma skin cancers (NMSCs) have occurred during treatment with etanercept, infliximab, and adalimumab in the setting of RA and psoriasis, but data related to AS are less clear. We report the case of a 29-year-old woman with AS treated with adalimumab for 2 years who developed invasive SCC of the lower lip. We advocate increased NMSC surveillance in patients undergoing treatment with anti-TNF-α agents.

Vitamin D deficiency, interleukin 17, and vascular function in rheumatoid arthritis.

OBJECTIVE: Vitamin D deficiency is associated with increased cardiovascular (CV) disease risk in the general population. We examined the association between vitamin D deficiency and CV risk in rheumatoid arthritis (RA). METHODS: We measured large artery compliance by pulse wave velocity and microvascular function by the reactive hyperemia index in patients with stable RA (n = 87). We quantified CV risk factors, serum 25-hydroxyvitamin D [25(OH)D], and interleukin 17 (IL-17), and RA disease activity by Disease Activity Score of 28 joints. We used linear regression to test associations between serum 25(OH)D and CV risk factors. RESULTS: The mean serum 25(OH)D level in the cohort was 27.1 ± SD 13.6 ng/ml. Fifty-nine patients (68%) were vitamin D-insufficient (25(OH)D < 30 ng/ml; mean 20.2 ± 5.9 ng/ml) and of these, 25 (29%) were vitamin D-deficient (25(OH)D < 20 ng/ml; mean 14.4 ± 3.4 ng/ml). In the whole cohort and the vitamin D-insufficient group, serum 25(OH)D was inversely associated with IL-17 (log IL-17; ß = -0.83, p = 0.04; ß = -0.63, p = 0.004, respectively) by univariate analysis, which persisted after adjustment for season, and in multivariate analysis after adjustment for confounders (log IL-17; ß = -0.74, p = 0.04; ß = -0.53, p = 0.02). In vitamin D-deficient patients, serum 25(OH)D was positively associated with microvascular function by univariate and multivariate analysis after adjustment for confounders (ß = 2.1, p = 0.04; ß = 2.7, p = 0.04). CONCLUSION: Vitamin D deficiency in RA may affect Th17 responses and microvascular function. Maintaining normal serum vitamin D levels may protect against IL-17-mediated inflammation and vascular dysfunction in RA.