Subtherapeutic hydroxychloroquine concentration is associated with increased disease activity and greater organ damage in lupus.

OBJECTIVE: To investigate the effects of the serum HCQ concentration on clinical manifestations, disease activity and organ damage in a longitudinal cohort of SLE patients. METHODS: The 338 SLE patients were assessed with respect to their demographic data, clinical and laboratory findings, Physician's Global Assessment (PGA), adjusted mean SLEDAI-2000 (AMS) and SLICC Damage Index (SDI) annually for 5 consecutive years. Patients were divided into two groups according to their serum HCQ concentration at baseline: subtherapeutic (<500 ng/ml) and therapeutic (≥500 ng/ml) groups. The impact of the HCQ concentration on the clinical outcomes was evaluated in a longitudinal analysis using a generalized estimating equation (GEE). RESULTS: Of the 338 patients, 287 (84.9%) were in the subtherapeutic group at baseline. This group had a higher incidence of newly developed LN (P = 0.036) and had been prescribed higher mean and cumulative doses of prednisolone (P = 0.003 and P = 0.013, respectively) than the therapeutic group. In multivariable analyses based on GEE, the subtherapeutic group had a higher AMS score (ß = 1.398, 95% CI 0.607, 2.189; P < 0.001), higher PGA score (ß = 0.328, 95% CI 0.215, 0.441; P < 0.001) and higher SDI score (ß = 0.366, 95% CI 0.061, 0.671; P = 0.019) across all 5 years. CONCLUSION: The subtherapeutic HCQ concentration was associated with the development of new-onset LN, and had significant associations with disease activity and cumulative organ damage in SLE patients over time.

Hydroxychloroquine-induced pigmentation in rheumatic diseases: prevalence, clinical features and influencing factors.

OBJECTIVE: To describe the clinical features of Chinese patients with hydroxychloroquine (HCQ)-induced pigmentation and analyze the potential risk factors associated with HCQ-induced pigmentation. METHODS: A cross-sectional study was conducted over a duration of 7 months, during which patients who had received HCQ treatment for >6 months were included. Data was collected through a structured questionnaire that encompassed demographic and geographic characteristics, information on HCQ and concomitant medication usage, sun exposure characteristics, and hyperpigmentation-related characteristics. Univariate and multivariate analyses were employed to calculate the statistical association between HCQ-induced pigmentation and multiple variables. RESULTS: Out of 316 patients, 83 (26.3%) patients presented hyperpigmentation during HCQ treatment. Hyperpigmentation presented after a median duration of HCQ treatment of 12 months (interquartile range, 6.0 months-30.0 months) with a median cumulative dose of 108 g of HCQ (interquartile range, 36-288 g). The most frequently affected sites of pigmentation were the face (60.2%), lower limbs (36.1%), and hands (20.5%). There was a linear decrease in the incidence of pigmentation with increasing daily sun exposure time (p= 0.030). In the multivariate analysis, variables (cumulative HCQ dose and daily sun exposure time) were included in the final models. The results revealed an independent correlation between HCQ-induced pigmentation and daily sun exposure exceeding 1 h (OR: 0.431; 95%CI: 0.208-0.892; p= 0.023). CONCLUSIONS: The occurrence of HCQ-induced pigmentation is not uncommon, with an incidence rate of 26.3%. Daily sun exposure time exhibited a protective effect against HCQ-induced pigmentation.

Anticoagulant and non-anticoagulant therapy in thrombotic antiphospholipid syndrome: old drugs and new treatment targets.

In this review, we discuss the current evidence on classic and newer oral anticoagulant therapy, older drugs such as HCQ and statins, and new potential treatment targets in APS. Vitamin K antagonists (VKAs) remain the cornerstone treatment for thrombotic events in APS. In patients fulfilling criteria for definite APS presenting with a first venous thrombosis, treatment with VKAs with a target international normalized ratio (INR) 2.0-3.0 is recommended. In patients with arterial thrombosis, treatment with VKA with target INR 2.0-3.0 or 3.0-4.0 is recommended by recent guidelines, considering the individual's bleeding and thrombosis recurrence risk. A combination of VKAs and low-dose aspirin (75-100 mg/daily) may also be considered. According to available evidence direct oral anticoagulants should be avoided in patients with arterial thrombosis and/or those with triple aPL positivity. Adjunctive treatment with HCQ and/or statins can be considered, especially in anticoagulation treatment-refractory APS. Potential targeted treatments in APS include B-cell targeting, complement inhibition, mammalian target of rapamycin inhibition, IFN targeting, adenosine receptors agonists, CD38 targeting or chimeric antigen receptor T-cell therapy. The safety and efficacy of these treatment targets needs to be examined in well-designed randomized controlled trials.

Accelerated hydroxychloroquine toxic retinopathy.

PURPOSE: To report a case series of patients with retinal toxicity due to hydroxychloroquine (HCQ) within a short span of treatment. METHODS: A retrospective review of case records of patients with accelerated HCQ toxicity within 1 year of starting the treatment was done. Systemic co-morbidities, details of HCQ treatment, details of ocular examination, and results of multimodal investigations were noted. RESULTS: Nine patients (1 male, 8 females) with age ranging from 40 to 73 years (mean 54.2 ± 13.4 years) who showed accelerated HCQ toxicity were included. None had systemic conditions or drug history predisposing to early HCQ toxicity. The treatment duration ranged from 2 to 11 months and the cumulative HCQ dose ranged from 18 to 120 g (mean 45.0 ± 33.0 g). The visual acuity was normal in 8 (88.9%) patients and retinal evaluation was normal in 4 (44.4%). Optical coherence tomography was abnormal in 4 (44.4%). Six (66.6%) cases had reduced sensitivity in the parafoveal point on visual field testing. All 9 cases had multifocal electroretinographic changes diagnostic of HCQ toxicity. The HCQ treatment was stopped in 8 and continued with reduced dose in 1 patient. The mean duration of follow-up was 11.2 ± 9.6 months during which 5 patients showed improved mfERG and 1 patient had a stable mfERG. Visual fields improvement was noted in 2 cases. CONCLUSIONS: Patients on HCQ need to be kept on regular monitoring with more frequent follow-ups to detect signs of early onset toxicity and prevent permanent visual impairment. mfERG is an important diagnostic tool for HCQ toxicity.

Outcomes of children born to mothers with systemic lupus erythematosus exposed to hydroxychloroquine or azathioprine.

OBJECTIVES: HCQ and AZA are used to control disease activity and reduce risk of flare during pregnancy in patients with SLE. The aim of this study was to determine the outcomes of children born to mothers with SLE exposed to HCQ or AZA during pregnancy and breast-feeding. METHODS: Women attending UK specialist lupus clinics with children ≤17 years old, born after SLE diagnosis, were recruited to this retrospective study. Data were collected using questionnaires and from clinical record review. Factors associated with the outcomes of low birth weight and childhood infection were determined using multivariable mixed-effects logistic regression models. RESULTS: We analysed 284 live births of 199 mothers from 10 UK centres. The first pregnancies of 73.9% of mothers (147/199) were captured in the study; (60.4%) (150/248) and 31.1% (87/280) children were exposed to HCQ and AZA, respectively. There were no significant differences in the frequency of congenital malformations or intrauterine growth restriction between children exposed or not to HCQ or AZA. AZA use was increased in women with a history of hypertension or renal disease. Although AZA was associated with low birth weight in univariate models, there was no significant association in multivariable models. In adjusted models, exposure to AZA was associated with increased reports of childhood infection requiring hospital management [odds ratio 2.283 (1.003, 5.198), P = 0.049]. CONCLUSIONS: There were no significant negative outcomes in children exposed to HCQ in pregnancy. AZA use was associated with increased reporting of childhood infection, which warrants further study.

Serum neurofilament-light and glial fibrillary acidic protein levels in hydroxychloroquine-treated primary progressive multiple sclerosis.

BACKGROUND: In a recent trial, hydroxychloroquine (HCQ) treatment reduced the expected rate of disability worsening at 18 months in primary progressive multiple sclerosis (PPMS). Neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) are emerging biomarkers in multiple sclerosis. METHODS: We measured NfL and GFAP levels in serum samples from 39 patients with inactive PPMS included in a phase II clinical trial of HCQ treatment in PPMS at multiple time points over 18 months, and investigated the association of these biomarkers with clinical disability at screening and during follow-up. Screening and 12-month retinal nerve fiber layer (RNFL) thickness was also recorded and analyzed. RESULTS: NfL and GFAP levels increased over time, but only significantly from screening to month 6. NfL and GFAP levels did not significantly increase from month 6 up to month 18. At screening, NfL and GFAP levels did not correlate with the Expanded Disability Status Scale (EDSS), and GFAP but not NfL modestly correlated with Timed 25-Foot Walk test (T25FW). Screening NfL and GFAP levels did not predict disability worsening (≥20% worsening on the T25FW) at month 18. RNFL thickness decreased significantly from screening to month 12 and independently predicted disability worsening. CONCLUSIONS: In this cohort of people with inactive PPMS, HCQ treatment attenuated the increase of NfL and GFAP after 6 months of treatment and up to 18 months of follow-up, suggesting a treatment effect of HCQ over these biomarkers. RNFL thickness, a marker of neuroaxonal atrophy, was associated with disability worsening, and should be explored further as a prognostic marker in this population.

Retinal microvascular density analysis in patients with rheumatoid arthritis treated with hydroxychloroquine.

PURPOSE: Rheumatoid arthritis (RA) is the most common inflammatory joint disease, and hydroxychloroquine (HCQ) is an established treatment. The extent to which HCQ impacts ocular microvascular vessel density (VD) in patients with RA without evidence of HCQ retinopathy has not yet been conclusively clarified. The main aim of this study was to evaluate VD measured by optical coherence tomography angiography (OCTA) in patients with RA treated with HCQ. METHODS: The VD data of the 3 × 3 mm OCT angiogram (RTVue XR Avanti, Optovue Inc., Fremont, California, USA) as well as the retinal thickness (RT) data of patients with RA (n = 30) and healthy controls (n = 30) were extracted and analyzed. The study group was further divided into patients undergoing HCQ treatment for > 5 years (high-risk-group) and < 5 years (low-risk group). RESULTS: Patients with RA showed no evidence of VD reduction compared to the control group in all obtained regions (p > 0.05). Correlation analysis revealed no dependency between VD, RT, and HCQ therapy duration or cumulative HCQ dose (p > 0.05). High-risk patients showed a decreased VD in the superficial quadrant of the superficial capillary plexus compared to low-risk-patients (p = 0.022). Whole-en-face RT was reduced in the high-risk group compared to the control group (p = 0.019). CONCLUSION: Our study showed no evidence that HCQ diminishes VD in patients with RA without HCQ retinopathy measured by OCTA. However, RA patients with a long duration of therapy showed a significantly reduced RT. Our results suggest that quantitative VD analysis by OCTA may not be suitable for early detection of HCQ retinopathy and that the focus on detecting early HCQ retinopathy should be on intensive and sequential OCT diagnostics.

The Impact of Hydroxychloroquine on Primary Feto-Placental Endothelial Cells from Healthy and Early-Onset Preeclamptic Placentas.

Hydroxychloroquine (HCQ), an anti-malarial drug, is suggested as a promising candidate for the treatment of pregnancy-related disorders associated with endothelial activation, among which there is preeclampsia (PE). Arterial feto-placental endothelial cells (fpECAs) were isolated from control (CTR) and early-onset preeclamptic (EO-PE) placentas. The aim of this study was to test potential protective effects of HCQ in an in vitro model of endothelial activation as well as in cells isolated from EO-PE placentas. To mimic PE conditions, CTR fpECAs were exposed to a pro-inflammatory environment consisting of tumor necrosis factor α (TNF-α), interleukin (IL)-6 and IL-1ß (furtherly referred as MIX) with or without varying concentrations of HCQ (1 µg/mL and 10 µg/mL). Their effect on wound healing and endothelial barrier integrity was analyzed. Variations in the expression of IL-8 and leukocyte adhesion molecules (LAM) on both mRNA and protein levels were determined between CTR and PE fpECAs in the presence or absence of HCQ. MIX decreased wound healing and stability of the endothelial barrier, but HCQ did not affect it. Significant differences between CTR and EO-PE fpECAs were observed in IL-8 mRNA, protein secretion, and vascular cell adhesion protein 1 (VCAM-1) mRNA expression levels. After challenging CTR fpECAs with MIX, upregulation of both mRNA and protein levels was observed in all molecules. Combined treatment of HCQ and MIX slightly lowered VCAM-1 total protein amount. In CTR fpECAs, treatment with low concentrations of HCQ alone (1 µg/mL) reduced basal levels of IL-8 and VCAM-1 mRNA and secretion of IL-8, while in EO-PE fpECAs, a higher (10µg/mL) HCQ concentration slightly reduced the gene expression of IL-8. Conclusion: These results provide additional support for the safety of HCQ, as it did not adversely affect endothelial functionality in control fpECAs at the tested concentration. Furthermore, the observed limited effects on IL-8 secretion in EO-PE fpECAs warrant further investigation, highlighting the need for clinical trials to assess the potential therapeutic effects of HCQ in preeclampsia. Conducting clinical trials would offer a more comprehensive understanding of HCQ's efficacy and safety, allowing us to explore its potential benefits and limitations in a real-world clinical setting.

ABCA3 Deficiency-Variant-Specific Response to Hydroxychloroquine.

Biallelic variants in ABCA3, the gene encoding the lipid transporter ATP-binding cassette subfamily A member 3 (ABCA3) that is predominantly expressed in alveolar type II cells, may cause interstitial lung diseases in children (chILD) and adults. Currently, there is no proven therapy, but, frequently, hydroxychloroquine (HCQ) is used empirically. We hypothesized that the in vitro responsiveness to HCQ might correlate to patients' clinical outcomes from receiving HCQ therapy. The clinical data of the subjects with chILD due to ABCA3 deficiency and treated with HCQ were retrieved from the literature and the Kids Lung Register data base. The in vitro experiments were conducted on wild type (WT) and 16 mutant ABCA3-HA-transfected A549 cells. The responses of the functional read out were assessed as the extent of deviation from the untreated WT. With HCQ treatment, 19 patients had improved or unchanged respiratory conditions, and 20 had respiratory deteriorations, 5 of whom transiently improved then deteriorated. The in vitro ABCA3 functional assays identified two variants with complete response, five with partial response, and nine with no response to HCQ. The variant-specific HCQ effects in vivo closely correlated to the in vitro data. An ABCA3+ vesicle volume above 60% of the WT volume was linked to responsiveness to HCQ; the HCQ treatment response was concentration dependent and differed for variants in vitro. We generated evidence for an ABCA3 variant-dependent impact of the HCQ in vitro. This may also apply for HCQ treatment in vivo, as supported by the retrospective and uncontrolled data from the treatment of chILD due to ABCA3 deficiency.

Hydroxychloroquine alleviates renal interstitial fibrosis by inhibiting the PI3K/Akt signaling pathway.

Renal fibrosis is the ultimate presentation of chronic kidney disease, which progresses to end-stage renal disease. Hydroxychloroquine (HCQ) has been adapted for the treatment of autoimmune diseases; however, the potential mechanism underlying the role of HCQ in renal fibrosis remains unclear. C57BL/6 J mice were randomly divided into three groups (sham group, UUO group, and UUO + HCQ group (20 mg/kg)). HE and Masson staining were performed to assess kidney tissue damage and fibrosis, and western blotting was performed to assess the expression of epithelial-mesenchymal transition (EMT), extracellular matrix (ECM), PI3K/AKT, and NF-κB-related proteins. PCR and TUNEL were adopted to detect inflammatory factors and cell apoptosis. HK-2 cells treated with TGF-ß1 were used for the in vitro experiments. HCQ may potentially have therapeutic effects on renal fibrosis mediated through 122 target genes, and the Kyoto Encyclopedia of Genes and Genomes pathways of these genes were enriched for PI3K/AKT signaling based on network pharmacology. UUO mice that received HCQ demonstrated significantly less tubular damage than the UUO mice. HCQ treatment additionally blunted EMT in UUO kidneys and TGF-ß1-treated renal tubular epithelial cells, and alleviated ECM deposition in kidney tissue. Furthermore, HCQ treatment reduced UUO-induced inflammation and apoptosis. Mechanistically, HCQ treatment suppressed the activation of the PI3K/Akt and NF-kB pathways. This study demonstrated that HCQ ameliorated renal fibrosis by inhibiting the PI3K/AKT and NF-κB signaling pathways to attenuate inflammatory factors and the apoptotic function of renal tubular epithelial cells, thus providing renewed theoretical evidence for HCQ treatment of renal fibrosis.

Risk of hydroxychloroquine retinopathy in the community.

OBJECTIVES: We aimed to estimate the risk of HCQ retinopathy and its risk factors among incident users in the community. METHODS: Using the Rochester Epidemiology Project, a record-linkage system, a cohort of incident users of HCQ was identified from 27 counties in the American upper Midwest. HCQ retinopathy was defined based on characteristic paracentral automated 10-2 visual field (10-2 AVF) defects and parafoveal retinal photoreceptor layer changes on spectral domain optical coherence tomography. Cumulative incidence rates were estimated adjusting for competing risk of death. Risk factors for HCQ retinopathy were examined using Cox models. RESULTS: The study included 634 incident HCQ users (mean age at initial HCQ use was 53.7 years, 79% females, 91% white). Most common indications for HCQ were RA (57%) and SLE (19%). The average follow-up length was 7.6 years. Eleven patients developed HCQ retinopathy (91% females, 91% white). The majority used HCQ for RA (91%). The cumulative incidence rate at year 5 was 0%, which increased to 3.9% (95% CI 2.0, 7.4) by 10 years. Taking an HCQ dose ≥5 mg/kg was associated with a hazard ratio (HR) of 3.59 (95% CI 1.09, 11.84) compared with lower doses. There was a 48% increase [HR 1.48 (95% CI 1.03, 2.14)] in the risk of HCQ retinopathy for each 100 g of HCQ cumulative dose. CONCLUSION: The risk of HCQ retinopathy at 10 years of use is lower compared with previous prevalence-based estimations. A dose ≥5 mg/kg was associated with higher HCQ retinopathy risk.

The synergistic efficacy of hydroxychloroquine with methotrexate is accompanied by increased erythrocyte mean corpuscular volume.

OBJECTIVES: To determine whether concomitant HCQ modulates the increase in erythrocyte mean corpuscular volume (MCV) caused by MTX therapy, and whether this is associated with improved clinical response in RA. METHODS: A retrospective observational analysis was conducted on two independent hospital datasets of biologic-naïve, early-RA patients who started oral MTX. Baseline characteristics, DAS28-ESR and monthly MCV after starting MTX were obtained. Conventional and machine-learning statistical approaches were applied to the discovery cohort (Cohort 1, 655 patients) and results validated using Cohort 2 (225 patients). RESULTS: HCQ therapy with MTX was associated with a 2-fold increase in the likelihood of response defined in this study as clinical remission or low disease activity at 6 months (P <0.001). The improved clinical outcome of combination HCQ and MTX therapy was associated with an accelerated rise in MCV from 2 months after commencing therapy. The increase in MCV at 3 months was equivalent to the contemporaneous reduction in the DAS (DAS28-ESR) in predicting clinical response at 6 months. Using latent class mixed modelling, five trajectories of MCV change over 6 months from baseline were identified. The odds ratio of response to treatment was 16.2 (95% CI 5.7, 46.4, P <0.001) in those receiving combination therapy classified within the MCV elevation >5 fl class, which contained the most patients, compared with MTX alone. CONCLUSION: Our data provide mechanistic insight into the synergistic clinical benefit of concomitant HCQ with MTX, boosting the rise in MCV, which could serve as a companion biomarker of treatment response.

Whole blood drug levels do not correlate with QTc intervals in hydroxychloroquine-treated systemic lupus erythematosus patients.

OBJECTIVES: HCQ is recommended for all patients with SLE, but reports of cardiac toxicity in severe acute respiratory syndrome coronavirus 2 patients raised concerns. We aimed to study the relationship between HCQ blood levels and QTc intervals. METHODS: A retrospective review of 90 SLE patients (cohort 1) was conducted with data collected regarding demographics, QTc interval and chronic kidney disease (CKD). A prospective study of 84 SLE patients (cohort 2) was conducted with data collected regarding demographics, dose of HCQ, duration of HCQ treatment, presence of echocardiographic abnormalities and CKD simultaneous with whole blood HCQ levels measured by HPLC. Statistical analysis utilized one-way analysis of variance, Pearson's correlation coefficient and t tests. RESULTS: In cohort 1 there was no significant difference in mean QTc based on 75 HCQ-treated [437.91 msec (s.d. 20.02)] as compared with 15 untreated patients [434.6 msec (s.d. 27.49)]. In patients with CKD, the mean QTc in HCQ users [448 (s.d. 23.37)] as compared with non-users [444.5 msec (s.d. 24.61)] also had no significant difference. In cohort 2, HCQ levels did not correlate with QTc interval (r = 0.017) and this applied regardless of the dose prescribed (r = 0.113 for 400 mg and r = 0.06 for 200 mg), duration of exposure (P = 0.36 for 0-5, >5-10 or >10 years), CKD (r = 0.482) or underlying cardiac abnormalities (r = 0.430). CONCLUSIONS: This is the first study relying on measured blood levels demonstrating the absence of a clinically consequential increase in QTc levels in HCQ-treated SLE patients.

Early onset monocular hydroxychloroquine maculopathy in a systemic lupus erythematosus patient with history of central retinal artery occlusion: a case report.

BACKGROUND: Hydroxychloroquine is a widely used medication for various clinical conditions mainly rheumatological and dermatological autoimmune diseases e.g. systemic lupus erythematosus, rheumatoid arthritis and psoriasis. While it is considered a safe medication, it is well-established that it can cause retinal toxicity i.e. HCQ maculopathy. Guidelines for HCQ retinal toxicity screening include factors like body weight, daily dose, duration, systemic diseases and retinal diseases. In this case study, we report a specific association between CRAO as a retinal disease and early onset HCQ maculopathy in a SLE patient. CASE PRESENTATION: A 42-year-old Caucasian female SLE patient presented with a complaint of gradual progressive painless diminution of vision in the left eye that started 16 months earlier. Clinical evaluation of the patient revealed a history of sudden profound painless diminution of vision in the same eye 18 months earlier after which the patient experienced only partial improvement of vision. That episode of sudden diminution of vision was attributed to left CRAO, complicating SLE-related thrombophilia, confirmed by fundus fluorescein angiography. Based on that diagnosis, the patient had been prescribed HCQ. At the time of presentation, fundus examination revealed left bull's eye maculopathy and right normal fundus. Therefore, a diagnosis of HCQ maculopathy in the left eye was made after exclusion of other causes of unilateral bull's eye maculopathy. CONCLUSION: Our case study is the first to report an association between CRAO as a specific retinal disease and early onset of HCQ maculopathy in a SLE patient. The unilateral bull's eye presentation which occurred in the eye with CRAO after only 16 months of HCQ treatment highly suggests that CRAO is probably the cause of such unusually early maculopathy. This case report highlights the importance of retinal diseases as risk factors for HCQ maculopathy. It also points out the lack of specific evidence concerning the association between specific retinal diseases and HCQ maculopathy.

Effect of hydroxychloroquine sulfate on the gelation behavior, water mobility and structure of gelatin.

Hydroxychloroquine sulfate (HCQ) is a well-established antimalarial drug that has received considerable attention during the COVID-19 associated pneumonia epidemic. Gelatin is a multifunctional biomacromolecule with pharmaceutical applications and can be used to deliver HCQ. The effect of HCQ on the gelation behaviors, water mobility, and structure of gelatin was investigated to understand the interaction between the drug and its delivery carrier. The gel strength, hardness, gelling (Tg) and melting (Tm) temperatures, gelation rate (kgel), and water mobility of gelatin decreased with increasing amounts of HCQ. The addition of HCQ led to hydrogen bonding that interfered with triple helix formation in gelatin. Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD) analysis further confirmed that the interaction between HCQ and gelatin is primarily through hydrogen bonding. Atomic force microscopy (AFM) revealed that higher content of HCQ resulted in more and larger aggregates in gelatin. These results provide not only an important understanding of gelatin for drug delivery design but also a basis for the studying interactions between a drug and its delivery carrier.

Hydroxychloroquine Mitigates Dilated Cardiomyopathy Phenotype in Transgenic D94A Mice.

In this study, we aimed to investigate whether short-term and low-dose treatment with hydroxychloroquine (HCQ), an antimalarial drug, can modulate heart function in a preclinical model of dilated cardiomyopathy (DCM) expressing the D94A mutation in cardiac myosin regulatory light chain (RLC) compared with healthy non-transgenic (NTg) littermates. Increased interest in HCQ came with the COVID-19 pandemic, but the risk of cardiotoxic side effects of HCQ raised concerns, especially in patients with an underlying heart condition, e.g., cardiomyopathy. Effects of HCQ treatment vs. placebo (H2O), administered in Tg-D94A vs. NTg mice over one month, were studied by echocardiography and muscle contractile mechanics. Global longitudinal strain analysis showed the HCQ-mediated improvement in heart performance in DCM mice. At the molecular level, HCQ promoted the switch from myosin's super-relaxed (SRX) to disordered relaxed (DRX) state in DCM-D94A hearts. This result indicated more myosin cross-bridges exiting a hypocontractile SRX-OFF state and assuming the DRX-ON state, thus potentially enhancing myosin motor function in DCM mice. This bottom-up investigation of the pharmacological use of HCQ at the level of myosin molecules, muscle fibers, and whole hearts provides novel insights into mechanisms by which HCQ therapy mitigates some abnormal phenotypes in DCM-D94A mice and causes no harm in healthy NTg hearts.

Systematic review and meta-analysis of effectiveness of treatment options against SARS-CoV-2 infection.

Treatment options for severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) are limited with no clarity on efficacy and safety profiles. We performed a systematic review and meta-analysis of studies on patients ≥18 years reporting data on therapeutic interventions in SARS-CoV-2. Primary outcome was all-cause mortality and secondary outcomes were rates of mechanical ventilation, viral clearance, adverse events, discharge, and progression to severe disease. Pooled rates and odds ratios (OR) were calculated. Twenty-nine studies with 5207 patients were included. Pooled all-cause mortality in intervention arm was 12.8% (95% confidence interval [CI]: 8.1%-17.4%). Mortality was significantly higher for studies using hydroxychloroquine (HCQ) for intervention (OR: 1.36; 95% CI: 0.97-1.89). Adverse events were also higher in HCQ subgroup (OR: 3.88; 95% CI: 1.60-9.45). There was no difference in other secondary outcomes. There is a need for well-designed randomized clinical trials for further investigation of every therapeutic intervention for further insight into different therapeutic options.

Association of antimalarial drugs with decreased overall and cause specific mortality in systemic lupus erythematosus.

OBJECTIVE: To evaluate the association and dose-response pattern between antimalarial drugs and overall and cause specific mortality in SLE patients. METHODS: Medical records including information on HCQ/chloroquine (CQ) prescription were extracted from Jiangsu Lupus database. The database was designed to collect data from SLE patients that first-hospitalized during 1999-2009 in Jiangsu province, China, and a follow-up for survival status was performed in 2010 and 2015. Cox and restricted cubic spline models were used to estimate the hazard ratio and 95% CI. RESULTS: We identified 221 deaths among 2446 SLE patients in total. Compared with non-users, decreased overall mortality was associated with either HCQ or CQ users, with adjusted hazard ratio (95% CI) of 0.49 (0.35, 0.67) and 0.49 (0.27, 0.87), respectively. The association between HCQ/CQ and overall mortality was similar across subgroups, such as patients with comorbidities and organ involvements. Interestingly, both the time and the daily dosage of HCQ/CQ use were related to decreased mortality of SLE in a linear dose-response relationship. In cause specific analyses, HCQ/CQ was inversely associated with death from renal insufficiency and other organ (cardiopulmonary, gastrointestinal and haematological) involvements, with adjusted hazard ratio (95% CI) of 0.23 (0.09, 0.55) and 0.25 (0.10, 0.62), respectively, yet it was not significantly associated with mortality from infection and neuropsychiatric involvements. CONCLUSION: Antimalarial drugs were associated with lower risk of SLE mortality, especially renal insufficiency- and other organ involvement-related death. The protective effects for survival might be augmented by adherence and full dosage of these drugs.

Risk of depression, suicide and psychosis with hydroxychloroquine treatment for rheumatoid arthritis: a multinational network cohort study.

OBJECTIVES: Concern has been raised in the rheumatology community regarding recent regulatory warnings that HCQ used in the coronavirus disease 2019 pandemic could cause acute psychiatric events. We aimed to study whether there is risk of incident depression, suicidal ideation or psychosis associated with HCQ as used for RA. METHODS: We performed a new-user cohort study using claims and electronic medical records from 10 sources and 3 countries (Germany, UK and USA). RA patients ≥18 years of age and initiating HCQ were compared with those initiating SSZ (active comparator) and followed up in the short (30 days) and long term (on treatment). Study outcomes included depression, suicide/suicidal ideation and hospitalization for psychosis. Propensity score stratification and calibration using negative control outcomes were used to address confounding. Cox models were fitted to estimate database-specific calibrated hazard ratios (HRs), with estimates pooled where I2 <40%. RESULTS: A total of 918 144 and 290 383 users of HCQ and SSZ, respectively, were included. No consistent risk of psychiatric events was observed with short-term HCQ (compared with SSZ) use, with meta-analytic HRs of 0.96 (95% CI 0.79, 1.16) for depression, 0.94 (95% CI 0.49, 1.77) for suicide/suicidal ideation and 1.03 (95% CI 0.66, 1.60) for psychosis. No consistent long-term risk was seen, with meta-analytic HRs of 0.94 (95% CI 0.71, 1.26) for depression, 0.77 (95% CI 0.56, 1.07) for suicide/suicidal ideation and 0.99 (95% CI 0.72, 1.35) for psychosis. CONCLUSION: HCQ as used to treat RA does not appear to increase the risk of depression, suicide/suicidal ideation or psychosis compared with SSZ. No effects were seen in the short or long term. Use at a higher dose or for different indications needs further investigation. TRIAL REGISTRATION: Registered with EU PAS (reference no. EUPAS34497; http://www.encepp.eu/encepp/viewResource.htm? id=34498). The full study protocol and analysis source code can be found at https://github.com/ohdsi-studies/Covid19EstimationHydroxychloroquine2.

Development of a SARS-CoV-2-derived receptor-binding domain-based ACE2 biosensor.

The global outbreak of coronavirus disease and rapid spread of the causative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represent a significant threat to human health. A key mechanism of human SARS-CoV-2 infection is initiated by the combination of human angiotensin-converting enzyme 2 (hACE2) and the receptor-binding domain (RBD) of the SARS-CoV-2-derived spike glycoprotein. Despite the importance of these protein interactions, there are still insufficient detection methods to observe their activity at the cellular level. Herein, we developed a novel fluorescence resonance energy transfer (FRET)-based hACE2 biosensor to monitor the interaction between hACE2 and SARS-CoV-2 RBD. This biosensor facilitated the visualization of hACE2-RBD activity with high spatiotemporal resolutions at the single-cell level. Further studies revealed that the FRET-based hACE2 biosensors were sensitive to both exogenous and endogenous hACE2 expression, suggesting that they might be safely applied to the early stage of SARS-CoV-2 infection without direct virus use. Therefore, our novel biosensor could potentially help develop drugs that target SARS-CoV-2 by inhibiting hACE2-RBD interaction.