Safety management in treatment with antimalarials in rheumatology. Interdisciplinary recommendations on the basis of a systematic literature review

Clinical features of ocular damage in systemic lupus erythematosus and risk factors of hydroxychloroquine related complications

Ocular damage in systemic lupus erythematosus (SLE) may cause insidious visual impairment, but its clinical features and the risk of hydroxychloroquine (HCQ)-related complications are still controversial. We performed a meta-analysis to evaluate ocular damage in SLE, the correlation between eye and systemic involvement, and the ocular side effects of treatment. The database PubMed, Embase, and Ovid were used for literature from reception to July, 2023, and the calculation was carried out with R. About 48,693 patients from 66 studies were included. The results indicated that ocular damage in SLE was insidious, appearing in 28% of patients with no complaints. The most common symptoms and manifestations were dry eye (30%) and keratoconjunctivitis sicca (26%). Retinopathy was detected in 10% of patients and was related to antiphospholipid antibodies (25% versus 8%). The proportion of retinopathy also significantly increased in patients with lupus nephropathy or neuropsychiatric systemic lupus erythematosus (risk ratio of 2.29 and 1.95, respectively). HCQ was used in 82% of patients, of which 4% suffered from ocular toxicity. HCQ-related retinopathy was dose-dependent. Dosage below 5mg/kg/d was relatively effective and safe for long-term use, while routine examination was recommended.

Chloroquine and Hydroxychloroquine in the Treatment of Dry Eye Disease

The role of chloroquine (CQ) and hydroxychloroquine (HCQ) in the management of dry eye disease is still unclear. This systematic review and meta-analysis investigates the efficacy and feasibility of CQ and HCQ in patients with dry eye disease. In February 2023, PubMed, Embase, Google Scholar, and Web of Science were accessed. Data from 462 patients (mean age 54.4 ± 2.8 years) were collected. Compared to baseline, the tear breakup time (p < 0.0001) and Schirmer I test (p < 0.0001) were significantly increased, and the Ocular Surface Disease Index (OSDI, p < 0.0001) and corneal staining (p < 0.0001) were significantly decreased at the last follow-up in the CQ/HCQ group. At the last follow-up, the OSDI was significantly lower in the CQ/HCQ group compared to the control group (p < 0.0001). Corneal staining was significantly greater in the control group compared to the CQ/HCQ group (p < 0.0001). The Schirmer I test showed no significant difference between the groups (p = 0.2). Altogether, CQ and HCQ improved the symptoms and signs of dry eye disease.

Hydroxychloroquine-Induced Myopathy Responding to Intravenous Immunoglobulin (IVIG)

Hydroxychloroquine (HCQ), a drug used to treat many diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), has limited reports documenting drug-induced myopathies as a side effect. This entity is underdiagnosed with unclear treatment interventions apart from discontinuing the offending drug. We report a case of a biopsy-proven hydroxychloroquine-induced myopathy in a 35-year-old female patient with SLE. The offending drug was stopped, but the patient did not improve. However, she showed marked improvement after the use of intravenous immunoglobulin (IVIG).

Association between cumulative dose of hydroxychloroquine and electrocardiographic abnormalities in patients with systemic lupus erythematosus

OBJECTIVE

Hydroxychloroquine (HCQ) is one of the most used drugs in patients with systemic lupus erythematosus (SLE). In these patients, where heart involvement is common, cardiac HCQ toxicity may lead to fatal outcomes. The aim of this work is to study the influence of cumulative HCQ (cHCQ) in a selected group of patients with SLE and its association with electrocardiographic (EKG) abnormalities.

METHODS

Single-center retrospective, observational study in which data were collected from the medical records of consecutive patients with a diagnosis of SLE who started treatment with HCQ and who had a 12-lead EKG before starting treatment and during follow-up. EKG abnormalities were grouped as conduction or structural abnormalities. The association of cHCQ with the occurrence of EKG disturbances was analyzed together with other demographic and clinical variables through univariate and multivariate logistic regression models.

RESULTS

105 patients were selected with median cHCQ of 913 g. The sample was classified into two groups, above or below 913 g. Significantly, more conduction disturbances were observed in the group above the median (OR: 2.89; 95%CI: 1.01-8.23). In the multivariate analysis, the OR per 100 g of cHCQ dose was 1.06 (95%CI: 0.99-1.14). Age was the only variable associated with conduction disturbances. There were no significant differences in the development of structural abnormalities and a tendency for more high-grade atrioventricular block was shown.

CONCLUSION

Our study suggests an association between the cHCQ and the development of EKG conduction disturbances that disappears after multivariate adjustment. No increased number of structural abnormalities was observed.

[Lupus nephritis]

Lupus nephritis (LN) is one of the most frequent organ manifestations of systemic lupus erythematosus. Urine analysis is suitable for screening and proteinuria or an active sediment with acanthocytes can be indicative for LN. The gold standard for confirming the diagnosis is a kidney biopsy. The type and extent of the histological alterations are decisive for treatment. The LN is histologically classified into six classes, whereby classes III, IV and V in particular require immunosuppressive treatment. The treatment of LN consists of the administration of hydroxychloroquine, angiotensin-converting enzyme (ACE) inhibitors for nephroprotection and further antihypertensive drugs in cases of arterial hypertension. For prognostically unfavorable forms of LN an immunosuppressive treatment is necessary and a variety of substances are available for this. The immunosuppressive treatment is spread over several years, whereby intensive treatment can mostly be de-escalated after 3-6 months. Despite good treatment options the risk of recurrence and also for chronic renal damage with terminal renal failure is elevated and continuous monitoring is absolutely necessary.

Hydroxychloroquine Ameliorates Hematuria in Children with X-Linked Alport Syndrome: Retrospective Case Series Study

Purpose

As a rare collagen type IV hereditary kidney disease, X-linked Alport syndrome (XLAS) is the most common form of Alport syndrome, the prevalence of which is estimated at 1:10,000 of the population, four times higher than the prevalence rate of autosomal recessive Alport syndrome. To describe a series of eight XLAS children with persistent hematuria and proteinuria and the clinical outcomes after hydroxychloroquine (HCQ) treatment to assess its efficacy as early intervention.

Patients and Methods

The study retrospectively analysed 8 patients with persistent hematuria and proteinuria at different onset ages who were diagnosed with XLAS and been treated with HCQ. The urinary erythrocyte count, urinary albuminn were measured. Descriptive statistics were used to estimate the patients' responses to HCQ treatment after one month, three months, and six months.

Results

After the first month, the three months, and the six months of HCQ treatment, the urinary erythrocyte counts of four, seven, and eight children were significantly reduced; the decreasing proteinuria was found in two, four, and five children. Only one child with increasing proteinuria was found after 1-month HCQ treatment. This proteinuria was maintained after 3-month HCQ treatment but decreased to minor after 6-month HCQ treatment.

Conclusion

We present the first potential efficacy of HCQ treatment in XLAS with hematuria and persistent proteinuria. It suggested that HCQ could be an effective treatment to ameliorate hematuria and proteinuria.

Consensus document of the Spanish Group for the Study of the Glomerular Diseases (GLOSEN) for the diagnosis and treatment of lupus nephritis

A significant number of patients with systemic lupus erythematosus (between 20% and 60% according to different reported series) develop lupus nephritis in the course of its evolution, which directly influences their quality of life and vital prognosis. In recent years, the greater knowledge about the pathogenesis of systemic lupus and lupus nephritis has allowed relevant advances in the diagnostic approach and treatment of these patients, achieving the development of drugs specifically aimed at blocking key pathogenic pathways of the disease. Encouragingly, these immunomodulatory agents have shown in well-powered, randomized clinical trials good clinical efficacy in the medium-term, defined as proteinuria remission and preservation of kidney function, with an acceptable safety profile and good patient tolerability. All this has made it possible to reduce the use of corticosteroids and other potentially more toxic therapies, as well as to increase the use of combined therapies. The present consensus document carried out by the Glomerular Diseases Working Group of the Spanish Society of Nephrology (GLOSEN), collects in a practical and summarized, but rigorous way, the best currently available evidence about the diagnosis, treatment, and follow-up of lupus nephritis patients, including cases of special situations, with the main objective of providing updated information and well-founded clinical recommendations to treating physicians, to improve the diagnostic and therapeutic approach to our patients.

Hydroxychloroquine safety in Covid-19 vs non-Covid-19 patients: analysis of differences and potential interactions

BACKGROUND

The use of hydroxychloroquine (HCQ) in the first COVID-19 epidemic wave raised safety concerns.

RESEARCH DESIGN AND METHODS

Adverse reactions (ADR) suspected to be induced by HCQ and submitted to the Spanish Pharmacovigilance Database were studied. A disproportionality analysis was performed to determine adverse effects reported in non-Covid and Covid patients. To explore potential drug-drug interactions, Omega (Ω) statistics was calculated.

RESULTS

More severe cases were reported when used in COVID-19. Main differences in frequency were observed in hepatobiliary, skin, gastrointestinal, eye, nervous system and heart ADRs. During the COVID-19 pandemic, high disproportionality in reports was found for Torsade de Pointes/QT prolongation with a ROR (-ROR) of 132.8 (76.7); severe hepatotoxicity, 18.7 (14.7); dyslipidaemias, 12.1 (6.1); shock, 9.5 (6.9) and ischemic colitis, 8.9 (2.6). Myopathies, hemolytic disorders and suicidal behavior increased their disproportionality during the pandemic. Disproportionality was observed for neoplasms, hematopoietic cytopaenias and interstitial lung disease in the pre-COVID-19 period. Potential interactions were showed between HCQ and azithromycin, ceftriaxone, lopinavir and tocilizumab.

CONCLUSIONS

The use of HCQ during the Covid-19 pandemic changed its ADRs reporting profile. Of particular concern during the pandemic were arrhythmias, hepatotoxicity, severe skin reactions and suicide, but not ocular disorders. Some signals identified would require more detailed analyses.

Synthetic Pharmacotherapy for Systemic Lupus Erythematosus: Potential Mechanisms of Action, Efficacy, and Safety

The pharmacological treatment of systemic lupus erythematosus (SLE) aims to decrease disease activity, progression, systemic compromise, and mortality. Among the pharmacological alternatives, there are chemically synthesized drugs whose efficacy has been evaluated, but which have the potential to generate adverse events that may compromise adherence and response to treatment. Therapy selection and monitoring will depend on patient characteristics and the safety profile of each drug. The aim of this review is to provide a comprehensive understanding of the most important synthetic drugs used in the treatment of SLE, including the current treatment options (mycophenolate mofetil, azathioprine, and cyclophosphamide), review their mechanism of action, efficacy, safety, and, most importantly, provide monitoring parameters that should be considered while the patient is receiving the pharmacotherapy.

Drug safety of frequently used drugs and substances for self-medication in COVID-19

During the COVID-19 pandemic, the behavior of self-medication has increased. The dissemination of misleading information regarding the efficacy of certain drugs or substances for the prevention and treatment of COVID-19 has been the major contributing factor for this phenomenon. Alongside with the increase in self-medication behavior, the inherent risks to this act such as drug-drug interactions, adverse events, drug toxicity, and masking of symptoms have also increased. Self-medication in the context of COVID-19 has led to drug misuse leading in some cases to the development of fatal adverse drug reactions. It is important that during this ongoing pandemic drugs with potential clinical efficacy against COVID-19 are adequately analyzed regarding their efficacy, safety, and monitoring. The aim of this review is to describe the available evidence regarding the efficacy, safety, and monitoring of the drugs and substances that have been shown to be frequently used for self-medication in patients with COVID-19 (hydroxychloroquine, non-steroidal anti-inflammatory drugs, ivermectin, azithromycin, vitamins, aspirin, and chlorine dioxide) to adequately characterize their risks, safe use, monitoring strategies, and to reinforce the concept that these substances should not be used for self-medication and require a medical prescription.

Plain Language Summary

Drug safety of frequently used drugs and substances for self-medication in COVID-19 Dissemination of information about potential COVID-19 treatments has led individuals to self-medicate and expose themselves to risks such as drug-drug interactions, side effects, antibiotic resistance, and misdiagnosis. There is a need to review the medical literature to evaluate the safety and efficacy of the drugs and substances commonly used by the population for the treatment and prevention of SARS CoV-2 infection. In this review, we included drugs that are frequently used for self-medication and commonly advertised such as ivermectin, hydroxychloroquine, chlorine dioxide, azithromycin, and non-steroidal anti-inflammatory drugs, among others. A brief introduction of the drug and its mechanism of action, followed by a summary of the efficacy in COVID-19 and safety, will be described for each drug in order to promote their responsible use.

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.

Management of Pediatric Chronic Spontaneous Urticaria: A Review of Current Evidence and Guidelines

Chronic urticaria (CU) is associated with debilitating symptoms such as pruritic wheals and/or angioedema, which can significantly affect patients’ sleep, productivity and quality of life. Chronic spontaneous urticaria (CSU) is defined in cases in which no triggering factor is identified. Various guidelines directing the optimal management of CU in the adult population were published and updated over the recent years with the most accepted and widely used being the EAACI/GA²LEN/EDF/WAO 2017 guidelines. Meanwhile, guidelines specific to the pediatric population are scarce, mainly due to the fact that high quality evidence is lacking for many treatment options in this age group. The objective of this article is to review and synthesize the existing literature regarding the management of pediatric CSU. Our review highlights evidence supporting the EAACI/GA²LEN/EDF/WAO 2017 treatment guidelines with non-sedating second-generation antihistamines (sgAHs) as the mainstay of treatment for pediatric CSU, considering their demonstrated efficacy and reassuring safety profile. Additionally, the use of omalizumab in adolescents is well supported by the current literature. There is limited data available regarding the updosing of sgAHs, omalizumab in children with CSU under 12 years of age and the treatment with cyclosporine and leukotriene receptor antagonists (LTRAs) in pediatric patients of all ages. However, the results from currently available case series and case reports are promising for omalizumab and cyclosporine use in children with CSU, although large and well-designed randomized control trials (RCTs) assessing these treatment options are needed in order to formulate strong recommendations for their use. First-generation antihistamines (fgAHs) remain commonly used in pediatric CSU treatment despite a lack of studies assessing their efficacy and safety in the pediatric population and their widely known inferior safety profile compared to sgAHs.

Chloroquine or hydroxychloroquine for prevention and treatment of COVID-19

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has resulted in substantial mortality. Some specialists proposed chloroquine (CQ) and hydroxychloroquine (HCQ) for treating or preventing the disease. The efficacy and safety of these drugs have been assessed in randomized controlled trials.

OBJECTIVES

To evaluate the effects of chloroquine (CQ) or hydroxychloroquine (HCQ) for 1) treating people with COVID-19 on death and time to clearance of the virus; 2) preventing infection in people at risk of SARS-CoV-2 exposure; 3) preventing infection in people exposed to SARS-CoV-2.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Current Controlled Trials (www.controlled-trials.com), and the COVID-19-specific resources www.covid-nma.com and covid-19.cochrane.org, for studies of any publication status and in any language. We performed all searches up to 15 September 2020. We contacted researchers to identify unpublished and ongoing studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) testing chloroquine or hydroxychloroquine in people with COVID-19, people at risk of COVID-19 exposure, and people exposed to COVID-19. Adverse events (any, serious, and QT-interval prolongation on electrocardiogram) were also extracted.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility of search results, extracted data from the included studies, and assessed risk of bias using the Cochrane 'Risk of bias' tool. We contacted study authors for clarification and additional data for some studies. We used risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous outcomes, with 95% confidence intervals (CIs). We performed meta-analysis using a random-effects model for outcomes where pooling of effect estimates was appropriate.

MAIN RESULTS

1. Treatment of COVID-19 disease We included 12 trials involving 8569 participants, all of whom were adults. Studies were from China (4); Brazil, Egypt, Iran, Spain, Taiwan, the UK, and North America (each 1 study); and a global study in 30 countries (1 study). Nine were in hospitalized patients, and three from ambulatory care. Disease severity, prevalence of comorbidities, and use of co-interventions varied substantially between trials. We found potential risks of bias across all domains for several trials. Nine trials compared HCQ with standard care (7779 participants), and one compared HCQ with placebo (491 participants); dosing schedules varied. HCQ makes little or no difference to death due to any cause (RR 1.09, 95% CI 0.99 to 1.19; 8208 participants; 9 trials; high-certainty evidence). A sensitivity analysis using modified intention-to-treat results from three trials did not influence the pooled effect estimate.  HCQ may make little or no difference to the proportion of people having negative PCR for SARS-CoV-2 on respiratory samples at day 14 from enrolment (RR 1.00, 95% CI 0.91 to 1.10; 213 participants; 3 trials; low-certainty evidence). HCQ probably results in little to no difference in progression to mechanical ventilation (RR 1.11, 95% CI 0.91 to 1.37; 4521 participants; 3 trials; moderate-certainty evidence). HCQ probably results in an almost three-fold increased risk of adverse events (RR 2.90, 95% CI 1.49 to 5.64; 1394 participants; 6 trials; moderate-certainty evidence), but may make little or no difference to the risk of serious adverse events (RR 0.82, 95% CI 0.37 to 1.79; 1004 participants; 6 trials; low-certainty evidence). We are very uncertain about the effect of HCQ on time to clinical improvement or risk of prolongation of QT-interval on electrocardiogram (very low-certainty evidence). One trial (22 participants) randomized patients to CQ versus lopinavir/ritonavir, a drug with unknown efficacy against SARS-CoV-2, and did not report any difference for clinical recovery or adverse events. One trial compared HCQ combined with azithromycin against standard care (444 participants). This trial did not detect a difference in death, requirement for mechanical ventilation, length of hospital admission, or serious adverse events. A higher risk of adverse events was reported in the HCQ-and-azithromycin arm; this included QT-interval prolongation, when measured. One trial compared HCQ with febuxostat, another drug with unknown efficacy against SARS-CoV-2 (60 participants). There was no difference detected in risk of hospitalization or change in computed tomography (CT) scan appearance of the lungs; no deaths were reported. 2. Preventing COVID-19 disease in people at risk of exposure to SARS-CoV-2 Ongoing trials are yet to report results for this objective. 3. Preventing COVID-19 disease in people who have been exposed to SARS-CoV-2 One trial (821 participants) compared HCQ with placebo as a prophylactic agent in the USA (around 90% of participants) and Canada. Asymptomatic adults (66% healthcare workers; mean age 40 years; 73% without comorbidity) with a history of exposure to people with confirmed COVID-19 were recruited. We are very uncertain about the effect of HCQ on the primary outcomes, for which few events were reported: 20/821 (2.4%) developed confirmed COVID-19 at 14 days from enrolment, and 2/821 (0.2%) were hospitalized due to COVID-19 (very low-certainty evidence). HCQ probably increases the risk of adverse events compared with placebo (RR 2.39, 95% CI 1.83 to 3.11; 700 participants; 1 trial; moderate-certainty evidence). HCQ may result in little or no difference in serious adverse events (no RR: no participants experienced serious adverse events; low-certainty evidence). One cluster-randomized trial (2525 participants) compared HCQ with standard care for the prevention of COVID-19 in people with a history of exposure to SARS-CoV-2 in Spain. Most participants were working or residing in nursing homes; mean age was 49 years. There was no difference in the risk of symptomatic confirmed COVID-19 or production of antibodies to SARS-CoV-2 between the two study arms.

AUTHORS' CONCLUSIONS

HCQ for people infected with COVID-19 has little or no effect on the risk of death and probably no effect on progression to mechanical ventilation. Adverse events are tripled compared to placebo, but very few serious adverse events were found. No further trials of hydroxychloroquine or chloroquine for treatment should be carried out. These results make it less likely that the drug is effective in protecting people from infection, although this is not excluded entirely. It is probably sensible to complete trials examining prevention of infection, and ensure these are carried out to a high standard to provide unambiguous results.

Hydroxychloroquine in the post-COVID-19 era: will this pandemic upset decades of clinical practice?

In the early stage of the COVID-19 pandemic, Belgian health authorities endorsed the interim guidelines for the treatment of COVID-19 pneumonia: hydroxychloroquine (HCQ) recommended for treatment of hospitalized patients with moderate to severe disease. As a growing number of patients were admitted, inevitably, our internal medicine team questioned the efficacy and safety of HCQ, especially with regard to cardiac side effects. In parallel with our concerns, data regarding the safety and efficacy of HCQ were published, with discordant results and debate in the medical community. Media coverage of the possible risks and benefits of HCQ use in COVID-19 also caused confusion amongst the public. In this Perspectives in Rheumatology article, we review the use and safety of HCQ in autoimmune disease and its putative efficacy and toxicity in COVID-19. Finally, we share our concern about the future of this widely used and inexpensive drug after the COVID-19 pandemic has passed.

Hydroxychloroquine and SARS-CoV-2 (COVID-19): An Old Problem and New Considerations in Ophthalmology

The antimalarial hydroxychloroquine (HCQ) has been suggested as a potential drug for treatment and prevention against severe acute respiratory syndrome–coronavirus 2 (SARS–CoV-2). Currently, there is insufficient scientific evidence available on HCQ retinal toxicity associated with the current treatment regimen and dosing for COVID-19 patients. In the sight of the current public health crisis, our recommendations aim to reduce the probability of unfavorable HCQ treatment outcomes and emphasize the importance of monitoring and early detection for HCQ retinopathy by simple means and the need for correlating clinical observations with multimodal imaging. We, therefore, recommend the use of Threshold Amsler grid (TAG) as a screening tool for high risk COVID-19 patients as well as treated patients with visual symptoms. Clinical decisions should be made on an individual basis, taking into consideration any pre-existing liver and kidney disease as well as macular pathology.

A Simple Bayesian Method for Evaluating Whether Data From Patients With Rheumatic Diseases Who Have Been Under Chronic Hydroxychloroquine Medication Since Before the COVID-19 Outbreak Can Speak to Hydroxychloroquine's Prophylactic Effect Against Infection With SARS-CoV-2

No vaccine against infection by SARS-CoV-2 yet exists. Treatment by hydroxychloroquine (HCQ) medication, among others, has been proposed. However, prophylactic HCQ medication has been little evaluated. We propose to use data from patients with rheumatic diseases (RA, SLR) who have been chronically taking HCQ medication since before the COVID-19 outbreak (hereafter: HCQpa), in order to evaluate the potential of HCQ for preventing infection with SARS-CoV-2. This can be achieved with relative ease by considering whether COVID-19 prevalence is significantly lower in HCQpa than in the general population (i.e., all people that are not HCQpa). Even if COVID-19 prevalence is truly significantly lower in HCQpa, some HCQpa may still present with COVID-19 (lower prevalence does not mean a prevalence of zero). However, given a value for COVID-19 prevalence in the general population and a number of available HCQpa, one may compute the maximum number of HCQpa for that total number of HCQpa considered that can have COVID-19 in order to still be able to conclude a lower COVID-19 prevalence in HCQpa (i.e., if there is one more case of COVID-19 than that maximum number, the COVID-19 prevalence in the HCQpa cannot be said to be lower than in the general population). Because the COVID-19 prevalence in the general population is not known with precision, we will consider different general population prevalence values. Among these contemplated prevalence values, one is derived from the official total number of confirmed cases, others by computing the total number of cases from the number of fatal COVID-19 cases so far and considering different case fatality rates per total cases. Our analyses show that systematic testing for COVID-19 in as few as 5,000 HCQpa is all that is needed for a test of whether HCQ has a prophylactic action against COVID-19, even for a COVID-19 prevalence value as low as 250 per 100,000, provided that test sensitivity is at least equal to its specificity. For higher COVID-19 prevalence values, the number of HCQpa needed is even lower.

Benefits and adverse effects of hydroxychloroquine, methotrexate and colchicine: searching for repurposable drug candidates

Repurposing of antirheumatic drugs has garnered global attention. The aim of this article is to overview available evidence on the use of widely used antirheumatic drugs hydroxychloroquine, methotrexate and colchicine for additional indications. Hydroxychloroquine has endothelial stabilizing and anti-thrombotic effects. Its use has been explored as an adjunctive therapy in refractory thrombosis in antiphospholipid syndrome. It may also prevent recurrent pregnancy losses in the absence of antiphospholipid antibodies. Hydroxychloroquine favourably modulates atherogenic lipid and glycaemic profiles. Methotrexate has been tried for modulation of cardiovascular events in non-rheumatic clinical conditions, although a large clinical trial failed to demonstrate a benefit. Colchicine has been shown to successfully reduce the risk of recurrent cardiovascular events in a large multicentric trial. Potential antifibrotic effects of colchicine require further exploration. Hydroxychloroquine, methotrexate and colchicine are also being tried at different stages of the ongoing Coronavirus Disease 19 (COVID-19) pandemic for prophylaxis and treatment. While the use of these agents is being diversified, their adverse effects should be timely diagnosed and prevented. Hydroxychloroquine can cause retinopathy and rarely cardiac and auditory toxicity, retinopathy being dose and time dependent. Methotrexate can cause transaminitis, cytopenias and renal failure, particularly in acute overdoses. Colchicine can rarely cause myopathies, cardiomyopathy, cytopenias and transaminitis. Strong evidence is warranted to keep balance between benefits of repurposing these old antirheumatic drugs and risk of their adverse effects.

Revisiting hydroxychloroquine and chloroquine for patients with chronic immunity-mediated inflammatory rheumatic diseases

Hydroxychloroquine and chloroquine, also known as antimalarial drugs, are widely used in the treatment of rheumatic diseases and have recently become the focus of attention because of the ongoing COVID-19 pandemic. Rheumatologists have been using antimalarials to manage patients with chronic immune-mediated inflammatory rheumatic diseases for decades. It is an appropriate time to review their immunomodulatory and anti-inflammatory mechanisms impact on disease activity and survival of systemic lupus erythematosus patient, including antiplatelet effect, metabolic and lipid benefits. We also discuss possible adverse effects, adding a practical and comprehensive approach to monitoring rheumatic patients during treatment with these drugs.