Blood concentrations of hydroxychloroquine and its desethyl derivative correlate negatively with the percentage of CD45RO+ cells among CD4+ lymphocytes in hydroxychloroquine-treated lupus patients

Current treatment of systemic lupus erythematosus: a clinician's perspective

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease. Its variable course makes it difficult to standardize patient treatment. This article aims at a literature review on available drugs for treating SLE and on drugs that have shown therapeutic effects in this disease. The PubMed/MEDLINE electronic search engine was used to identify relevant studies. This review presents the current therapeutic options, new biological therapies, and combination therapies of biologics with standard immunosuppressive and immunomodulating drugs. We have also underlined the importance to implement the treat-to-target strategy aimed at reducing or discontinuing therapy with glucocorticosteroids (GCs). The awareness of the benefits and risks of using GCs helps in refining their dosage and thereby obtaining a better safety profile. The advent of biological targeted therapies, and more recently, low-molecular-weight compounds such as kinase inhibitors, initiated numerous clinical trials in SLE patients and led to the approval of two biological drugs, belimumab, and anifrolumab, for SLE treatment. Progress in the treatment of SLE was reflected in the 2019 and 2021 recommendations of the European Alliance of Associations for Rheumatology (EULAR). However, a mass of recent clinical research data requires continuous consolidation to optimize patient outcomes.

Hydroxychloroquine in systemic lupus erythematosus: overview of current knowledge

The antimalarial hydroxychloroquine (HCQ) has demonstrated several crucial properties for the treatment of systemic lupus erythematosus (SLE). Herein, we reviewed the main HCQ pharmacologic features, detailed its mechanism of action, and summarized the existing guidelines and recommendations for HCQ use in rheumatology with a systematic literature search for the randomized controlled trials focused on lupus. HCQ has been shown to decrease SLE activity, especially in mild and moderate disease, to prevent disease flare and to lower the long-term glucocorticoid need. The numerous benefits of HCQ are extended to pregnancy and breastfeeding period. Based on cohort studies, antithrombotic and metabolic HCQ’s effects were shown, including lipid-lowering properties, which might contribute to an improved cardiovascular risk. Moreover, early HCQ use in antinuclear antibodies positive individuals might delay the progression to SLE. Finally, HCQ has a significant favorable impact on long-term outcomes such as damage accrual and mortality in SLE. Based on these multiple benefits, HCQ is now the mainstay long-term treatment in SLE, recommended by current guidelines in all patients unless contraindications or side effects. The daily dose associated with the best compromise between efficacy and safety is matter of debate. The concern regarding retinal toxicity rather than proper efficacy data is the one that dictated the daily dosage of ⩽5 mg/kg/day actual body weight currently agreed upon.

A Prospective International Study on Adherence to Treatment in 305 Patients With Flaring SLE: Assessment by Drug Levels and Self-Administered Questionnaires

Nonadherence to treatment is a major cause of lupus flares. Hydroxychloroquine (HCQ), a major medication in systemic lupus erythematosus, has a long half-life and can be quantified by high-performance liquid chromatography. This international study evaluated nonadherence in 305 lupus patients with flares using drug levels (HCQ <200 ng/ml or undetectable desethylchloroquine), and self-administered questionnaires (MASRI <80% or MMAS-8 <6). Drug levels defined 18.4% of the patients as severely nonadherent. In multivariate analyses, younger age, nonuse of steroids, higher body mass index, and unemployment were associated with nonadherence by drug level. Questionnaires classified 39.9% of patients as nonadherent. Correlations between adherence measured by questionnaires, drug level, and physician assessment were moderate. Both methods probably measured two different patterns of nonadherence: self-administered questionnaires mostly captured relatively infrequently missed tablets, while drug levels identified severe nonadherence (i.e., interruption or erratic tablet intake). The frequency with which physicians miss nonadherence, together with underreporting by patients, suggests that therapeutic drug monitoring is useful in this setting. (Trial registration: ClinicalTrials.gov: NCT01509989.).

Hydroxychloroquine inhibits CD154 expression in CD4+ T lymphocytes of systemic lupus erythematosus through NFAT, but not STAT5, signaling

Background

Overexpression of membranous CD154 in T lymphocytes has been found previously in systemic lupus erythematosus (SLE). Because hydroxychloroquine (HCQ) has been used frequently in the treatment of lupus, we sought to identify the effects of HCQ on CD154 and a possibly regulatory mechanism.

Methods

CD4⁺ T cells were isolated from the blood of lupus patients. After stimulation with ionomycin or IL-15 and various concentrations of HCQ, expression of membranous CD154 and NFAT and STAT5 signaling were assessed.

Results

HCQ treatment had significant dose-dependent suppressive effects on membranous CD154 expression in ionomycin-activated T cells from lupus patients. Furthermore, HCQ inhibited intracellular sustained calcium storage release, and attenuated the nuclear translocation of NFATc2 and the expression of NFATc1. However, CD154 expressed through IL-15-mediated STAT5 signaling was not inhibited by HCQ treatment.

Conclusions

HCQ inhibited NFAT signaling in activated T cells and blocked the expression of membranous CD154, but not STAT5 signaling. These findings provide a mechanistic insight into SLE in HCQ treatment.

Factors Related to Blood Hydroxychloroquine Concentration in Patients With Systemic Lupus Erythematosus

OBJECTIVE

To identify factors associated with blood concentrations of hydroxychloroquine (HCQ) and its major metabolite, N-desethylhydroxychloroquine (DHCQ), in patients with systemic lupus erythematosus (SLE; lupus) receiving long-term oral HCQ treatment.

METHODS

SLE patients who had been taking HCQ for more than 3 months were recruited. Various clinical characteristics, laboratory values, and SLE Disease Activity Index (SLEDAI) scores were examined. The concentrations of HCQ and DHCQ ([HCQ] and [DHCQ]) were measured by liquid chromatography mass spectrometry, and the relationship between [HCQ], [DHCQ], and [HCQ]:[DHCQ] ratio to various factors was investigated.

RESULTS

In total, 189 SLE patients receiving long-term HCQ treatment were included in the analysis. The median (interquartile range [IQR]) [HCQ] was 515 (IQR 353-720) ng/ml, the median [DHCQ] was 417 (IQR 266-591) ng/ml, and the median [HCQ]:[DHCQ] ratio was 1.3 (range 1.0-1.7). [HCQ] was closely associated with [DHCQ] (r = 0.81, P < 0.0001). The weight-adjusted oral HCQ dose was strongly associated with both [HCQ] (P < 0.001) and [DHCQ] (P < 0.001). Time since last dose was associated with [HCQ] (P < 0.001). No statistically significant association was found between renal function or smoking and [HCQ] or [DHCQ]. Use of additional immunosuppressants increased both [HCQ] and [DHCQ] after adjusting for possible confounders (P = 0.04 and P = 0.03, respectively). The lower SLEDAI score was significantly related to higher [HCQ], after adjusting for age, sex, weight-adjusted HCQ dose, time since last dose, number of other immunosuppressants, and smoking status (P = 0.007).

CONCLUSION

Various factors affected blood levels of [HCQ], [DHCQ], or the [HCQ]:[DHCQ] ratio of SLE patients receiving long-term oral HCQ treatment. Notably, higher [HCQ] was associated with a lower SLEDAI score in our typical outpatient clinic population with lupus.

Association of Polymorphisms of Cytochrome P450 2D6 With Blood Hydroxychloroquine Levels in Patients With Systemic Lupus Erythematosus

OBJECTIVE

To evaluate associations of genetic polymorphisms in cytochrome P450 (CYP) isoforms 2D6, 3A5, and 3A4 with blood concentrations of hydroxychloroquine (HCQ) and its metabolite, N-desethyl HCQ (DHCQ), in patients with systemic lupus erythematosus (SLE).

METHODS

SLE patients taking HCQ for >3 months were recruited and were genotyped for 4 single-nucleotide polymorphisms in CYP2D6*10, CYP3A5*3, and CYP3A4*18B. Blood HCQ and DHCQ concentrations ([HCQ] and [DHCQ]) were measured and their association with corresponding genotypes was investigated.

RESULTS

A total of 194 patients were included in the analysis. CYP2D6*10 polymorphisms (rs1065852 and rs1135840) were significantly associated with the [DHCQ]:[HCQ] ratio after adjustment for age, sex, dose per weight per day, and SLE Disease Activity Index score (P = 0.03 and P < 0.01, respectively). In adjusted models, the [DHCQ]:[HCQ] ratio was highest in patients with the G/G genotype of the CYP2D6*10 (rs1065852) polymorphism and lowest in those with the A/A genotype (P = 0.03). Similarly, the [DHCQ]:[HCQ] ratio was highest in patients with the C/C genotype of the CYP2D6*10 (rs1135840) polymorphism and lowest in those with the G/G genotype (P < 0.01). The CYP2D6*10 (rs1065852) polymorphism was significantly related to the [DHCQ] (P = 0.01). However, the polymorphisms of CYP3A5*3 and CYP3A4*18B did not show any significant association with the [HCQ], [DHCQ], or [DHCQ]:[HCQ] ratio.

CONCLUSION

Our study showed that the [DHCQ]:[HCQ] ratio was related to CYP2D6 polymorphisms in Korean lupus patients taking oral HCQ. CYP polymorphisms may explain why there is wide variation in blood HCQ concentrations. The role of an individual's CYP polymorphisms should be considered when prescribing oral HCQ.

Memory Stem T Cells in Autoimmune Disease: High Frequency of Circulating CD8+ Memory Stem Cells in Acquired Aplastic Anemia

Memory stem T cells (TSCMs) constitute a long-lived, self-renewing lymphocyte population essential for the maintenance of functional immunity. Hallmarks of autoimmune disease pathogenesis are abnormal CD4(+) and CD8(+) T cell activation. We investigated the TSCM subset in 55, 34, 43, and 5 patients with acquired aplastic anemia (AA), autoimmune uveitis, systemic lupus erythematosus, and sickle cell disease, respectively, as well as in 41 age-matched healthy controls. CD8(+) TSCM frequency was significantly increased in AA compared with healthy controls. An increased CD8(+) TSCM frequency at diagnosis was associated with responsiveness to immunosuppressive therapy, and an elevated CD8(+) TSCM population after immunosuppressive therapy correlated with treatment failure or relapse in AA patients. IFN-γ and IL-2 production was significantly increased in various CD8(+) and CD4(+) T cell subsets in AA patients, including CD8(+) and CD4(+) TSCMs. CD8(+) TSCM frequency was also increased in patients with autoimmune uveitis or sickle cell disease. A positive correlation between CD4(+) and CD8(+) TSCM frequencies was found in AA, autoimmune uveitis, and systemic lupus erythematosus. Evaluation of PD-1, CD160, and CD244 expression revealed that TSCMs were less exhausted compared with other types of memory T cells. Our results suggest that the CD8(+) TSCM subset is a novel biomarker and a potential therapeutic target for AA.

Determinants of medication non-adherence in Egyptian patients with systemic lupus erythematosus: Sharkia Governorate

The aim of the study was to identify the determinants of adherence to medication among Egyptian patients with SLE. A single-center cross-sectional study was conducted among Egyptian patients with SLE. Adherence to medication was measured via The Compliance Questionnaire for Rheumatology-19, and the patients were classified as non-adherers if they were taking <80% of their medication correctly. Predictors of adherence to SLE medication were determined by multiple logistic regressions. The mean age of participants was 30.9 ± 11.7 years. Females constituted 95% of all participants. Thirty-eight (%) were taking <80% of their medication correctly. On logistic regression analysis, the significant independent predictors of medication non-adherence were lower educational level (OR 5.6, 95% CI 2.1-7.3, P < 0.001), very low and low socioeconomic status (OR 2.6, 95% CI 1.6-4.3, P < 0.04), rural residency (OR 3.4, 95% CI 1.4-5, P < 0.01), more number of medications (OR 3.2, 95% CI 2.3-6.9, P < 0.01), and higher depressive symptoms (OR 3.7, 95% CI 1.4-10.2, P < 0.001). The adherence rate reported in this study was quite low. Appropriate adherence enhancing intervention strategies targeted at reducing pill load, minimizing depressive symptoms, and ensuring an uninterrupted access to free services regimen for patients with low socioeconomic status is strongly recommended. More attention should be given to SLE patients who live in rural regions.

Measuring therapeutic adherence in systemic lupus erythematosus with electronic monitoring

Objective: We used an electronic monitoring system to quantify adherence to prescribed oral therapies by patients with systemic lupus erythematosus (SLE). Methods: Participants were included from a larger longitudinal study cohort of 110 patients recruited from publicly-funded rheumatology clinics, 78 of whom agreed to have their SLE drug therapy electronically monitored for two years with the Medication Events Monitoring System (MEMS®, AARDEX Group). Adherence was determined as the percentage of days (weeks for methotrexate) the patient took the medication as prescribed by the physician. Collected data included SLEDAI; SLICC damage index for SLE (SDI); medical outcome study social support survey (MOS-SSS); Center for Epidemiologic Studies depression scale (CESD); and quality of life (SF-12). Results: Ninety percent of the cohort was female, 45% were Hispanic, and 49% were African-American. Mean age was 36.3 years, disease duration was 5.9 years, SLEDAI score was 3.2, and SDI score was 0.9. Adherence was 62% for all drugs combined and did not differ significantly for individual medications. Patients with more depression ( p < 0.02), and higher number of pills taken daily ( p < 0.02) were more likely to be non-adherent. Only one-fourth of the patients had an average adherence of ≥80%; these patients had a better mental component score (SF-12) at 24 months than non-adherent patients ( p < 0.01). Conclusions: Electronic monitoring demonstrated that only one-fourth of the patients had an adherence rate ≥80%. Polypharmacy and depression were associated with non-adherence.

Treatment adherence to disease-modifying antirheumatic drugs in patients with rheumatoid arthritis and systemic lupus erythematosus

Treatment adherence is critical in the management of rheumatic diseases. Recent advances in therapy for rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) are promising, although the impact on quality of life may be limited due to nonadherence. Databases including Ovid Medline, Scopus and the Epub-ahead-of-print subset of PubMed were searched for the period of the last 10 years using combined keywords patient compliance, medication adherence, disease modifying antirheumatic drug (DMARD), rheumatoid arthritis and systemic lupus erythematosus. Additional references from retrieved papers were considered. Inclusion criteria were the following: identification of a quantitative measure of adherence to medications including DMARDs and biologics; inclusion of well-defined measures of adherence; and patients with RA or SLE. Studies in RA and SLE patients demonstrated overall inadequate treatment adherence. Adherence was measured using multiple methods including pharmacy records, electronic monitoring, self-report and physician report. The evidence for interventions to improve treatment adherence was limited and demonstrated various results. Future research should further explore determinants of nonadherence and continue to examine the efficacy of implementing various strategies to improve medication management in this patient population.

Quantification and molecular characterization of regulatory T cells in connective tissue diseases

The aim of our study was to investigate and characterize regulatory T cells (Treg) in peripheral blood of patients with connective tissue diseases (Systemic lupus erythematosus, systemic sclerosis, Sjögren's syndrome, poly- and dermatomyositis) as compared with blood from healthy controls. Treg cells were quantified and phenotypically characterized by flow cytometry while the expression level of Foxp3 mRNA was evaluated by real time PCR. A reduced percentage of peripheral blood Treg cells was found in patients than in controls, irrespective of the type of connective tissue disease. Treg cells, especially those expressing one of the phenotypical markers, seemed to differ not only between patients and healthy controls but also among types of diseases. Additionally, the presence of autoantibodies as well as disease activity appeared to be correlated with particular Treg cell populations, especially those expressing one of the examined phenotypical markers. Correlations with therapy suggested that glucocorticoids plus antimalarial or other immunosuppressor drugs diminished the percentage of Treg cells, especially of those with memory phenotype. These findings indicated dysregulations at the level of Treg cells and suggested an involvement of these cells in the pathology of connective tissue diseases. Moreover, our data are in agreement with the suggestion that Treg cells could be therapeutic targets for some autoimmune diseases.