Systematic review of registered trials of Hydroxychloroquine prophylaxis for COVID-19 health-care workers at the first third of 2020

Systematic review and meta-analysis of randomized trials of hydroxychloroquine for the prevention of COVID-19

Background

Recruitment into randomized trials of hydroxychloroquine (HCQ) for prevention of COVID-19 has been adversely affected by a widespread conviction that HCQ is not effective for prevention. In the absence of an updated systematic review, we conducted a meta-analysis of randomized trials that study the effectiveness of HCQ to prevent COVID-19.

Methods

A search of PubMed, medRxiv, and clinicaltrials.gov combined with expert consultation found 11 completed randomized trials: 7 pre-exposure prophylaxis trials and 4 post-exposure prophylaxis trials. We obtained or calculated the risk ratio of COVID-19 diagnosis for assignment to HCQ versus no HCQ (either placebo or usual care) for each trial, and then pooled the risk ratio estimates.

Results

The pooled risk ratio estimate of the pre-exposure prophylaxis trials was 0.72 (95% CI: 0.58–0.90) when using either a fixed effect or a standard random effects approach, and 0.72 (95% CI: 0.55–0.95) when using a conservative modification of the Hartung-Knapp random effects approach. The corresponding estimates for the post-exposure prophylaxis trials were 0.91 (95% CI: 0.72–1.16) and 0.91 (95% CI: 0.62–1.35). All trials found a similar rate of serious adverse effects in the HCQ and no HCQ groups.

Discussion

A benefit of HCQ as prophylaxis for COVID-19 cannot be ruled out based on the available evidence from randomized trials. However, the “not statistically significant” findings from early prophylaxis trials were widely interpreted as definite evidence of lack of effectiveness of HCQ. This interpretation disrupted the timely completion of the remaining trials and thus the generation of precise estimates for pandemic management before the development of vaccines.

Current status and strategic possibilities on potential use of combinational drug therapy against COVID-19 caused by SARS-CoV-2

The spread of new coronavirus infection starting December 2019 as novel SARS-CoV-2, identified as the causing agent of COVID-19, has affected all over the world and been declared as pandemic. Approximately, more than 8,807,398 confirmed cases of COVID-19 infection and 464,483 deaths have been reported globally till the end of 21 June 2020. Until now, there is no specific drug therapy or vaccine available for the treatment of COVID-19. However, some potential antimalarial drugs like hydroxychloroquine and azithromycin, antifilarial drug ivermectin and antiviral drugs have been tested by many research groups worldwide for their possible effect against the COVID-19. Hydroxychloroquine and ivermectin have been identified to act by creating the acidic condition in cells and inhibiting the importin (IMPα/β1) mediated viral import. There is a possibility that some other antimalarial drugs/antibiotics in combination with immunomodulators may help in combatting this pandemic disease. Therefore, this review focuses on the current use of various drugs as single agents (hydroxychloroquine, ivermectin, azithromycin, favipiravir, remdesivir, umifenovir, teicoplanin, nitazoxanide, doxycycline, and dexamethasone) or in combinations with immunomodulators additionally. Furthermore, possible mode of action, efficacy and current stage of clinical trials of various drug combinations against COVID-19 disease has also been discussed in detail.Communicated by Ramaswamy H. Sarma.

Serosurvey for Health-Care Workers Provides Supportive Evidence for the Effectiveness of Hydroxychloroquine Prophylaxis against SARS-CoV-2 Infection

Background: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic has resulted in occupational exposure among Healthcare Workers (HCWs) and a high risk of nosocomial transmission. Asymptomatic infection and transmission of infection before the development of symptoms are well-recognized factors contributing to the spread of infection. We conducted a cross-sectional observational study to understand the seroprevalence of SARS-CoV-2 infection among HCWs and to verify the appropriateness of infection control measures, particularly Hydroxychloroquine (HCQ) prophylaxis.

Methods: A cross-sectional sero-surveillance study was conducted among 500 HCWs in Dombivli and surrounding Mumbai Metropolitan area (Maharashtra, India) between 21st July and 3rd August 2020. The vulnerability of the study participants to SARS-CoV-2 infection was ascertained through a history of (i) involvement in direct care, (ii) exposure to aerosol-generating procedures, (iii) co-morbidities, (iv) Personal Protective Equipment (PPE) use, and (v) HCQ prophylaxis. SARS-CoV-2 IgG antibodies were tested using COVID KAVACH anti-SARS-CoV-2 IgG antibody detection enzyme-linked immunosorbent assay (ELISA) from Zydus Cadila. A systematic analysis of the correlation between the development of antibodies and factors affecting vulnerability to infection was performed.

Results: The overall SARS-CoV-2 seroprevalence in the study population was 11%. Providing direct care to COVID-19 patients (Adjusted OR 16.4, 95% CI 3.3–126.9, p = 0.002) for long hours and irregular use of PPE (Adjusted OR 3.78, 95% CI 1.1–11.9, p = 0.02) were associated with an increased incidence of seropositivity. Prophylaxis with HCQ may have a role in reducing the vulnerability to infection as depicted by univariate and multivariate analysis (Adjusted OR 0.55, 95% CI 0.3–0.9, p = 0.047). It was also noted that those not on HCQ prophylaxis were threefold more prone to infection and developed severe disease as compared to those on HCQ prophylaxis.

Conclusion: Prophylaxis with HCQ may have a role in mitigating the incidence and severity of SARS-CoV-2 infection. Although vaccination is the most robust strategy to safeguard against COVID-19, it will be months before vaccination percolates to the masses. In the face of the second wave of COVID-19, the use of HCQ prophylaxis in combination with use of face-masks regularly may be considered as a cost-effective measure for population dense areas like urban slums where social distancing is not possible.

Safety of hydroxychloroquine in healthcare workers for COVID-19 prophylaxis

BACKGROUND & OBJECTIVES

Hydroxychloroquine (HCQ), reported to inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in in vitro studies, has been recommended for prophylaxis of COVID-19 in healthcare workers (HCWs). The objective of this study was to assess short-term adverse events (AEs) of HCQ in HCWs.

METHODS

This cross-sectional study among consenting HCWs taking prophylaxis and working in hospitals with COVID-19 patients used online forms to collect details of HCWs, comorbidities, prophylactic drugs used and AEs after the first dose of HCQ. Verification of dose and AEs was done by personal contact. Multivariate logistic regression analysis was done to determine the effect of age, gender and dose of HCQ on AE.

RESULTS

Of the 1303 HCWs included, 98.4 per cent (n=1282) took HCQ and 66 per cent (n=861) took 800 mg as first day's dose. Among the 19.9 per cent (n=259) reporting AEs, 1.5 per cent (n=20) took treatment for AE, none were hospitalized and three discontinued HCQ. Gastrointestinal AEs were the most common (172, 13.2%), with less in older [odds ratio (OR) 0.56, 95% confidence interval (CI) 0.35-0.89], with more in females (OR 2.46, 95% CI 1.78-3.38) and in those taking a total dose of 800 mg on day one compared to a lower dose. Hypoglycaemia (1.1%, n=14), cardiovascular events (0.7%, n=9) and other AEs were minimal.

INTERPRETATION & CONCLUSIONS

HCQ prophylaxis first dose was well tolerated among HCWs as evidenced by a low discontinuation. For adverse effects, a small number required treatment, and none required hospitalization. The study had limitations of convenience sampling and lack of laboratory and electrocardiography confirmation of AEs.

Chloroquine and hydroxychloroquine for COVID-19: Perspectives on their failure in repurposing

WHAT IS KNOWN AND OBJECTIVE

Non-clinical studies suggest that chloroquine (CQ) and hydroxychloroquine (HCQ) have antiviral activities. Early clinical reports of successful HCQ-associated reduction in viral load from small studies in COVID-19 patients spurred a large number of national and international clinical trials to test their therapeutic potential. The objective of this review is to summarize the current evidence on the safety and efficacy of these two agents and to provide a perspective on why their repurposing has hitherto failed.

METHODS

Published studies and rapidly emerging data were reviewed to gather evidence on safety and efficacy of CQ and HCQ in patients with COVID-19 infection or as prophylaxis. The focus is on clinically relevant efficacy endpoints and their adverse effects on QT interval.

RESULTS AND DISCUSSION

At the doses used, the two agents, given alone or with azithromycin (AZM), are not effective in COVID-19 infection. The choice of (typically subtherapeutic) dosing regimens, influenced partly by "QT-phobia," varied widely and seems anecdotal without any pharmacologically reliable supporting clinical evidence. A substantial proportion of patients receiving CQ/HCQ/AZM regimen developed QTc interval prolongation, many with absolute QTc interval exceeding the potential proarrhythmic threshold, but very few developed proarrhythmia.

WHAT IS NEW AND CONCLUSION

The strategy to repurpose CQ/HCQ to combat COVID-19 infection is overshadowed by concerns about their QT liability, resulting in choice of potentially subtherapeutic doses. Although the risk of QT-related proarrhythmia is real, it is low and manageable by careful monitoring. Recent discontinuation of HCQ from at least four large studies effectively marks the end of efforts at repurposing of CQ or HCQ for COVID-19 infection. This episode leaves behind important questions on dose selection and risk/benefit balance in repurposing drugs generally.

Hydroxychloroquine as Prophylaxis for COVID-19: A Review

The impact of the COVID-19 pandemic worldwide has led to a desperate search for effective drugs and vaccines. There are still no approved agents for disease prophylaxis. We thus decided to use a drug repositioning strategy to perform a state-of-the-art review of a promising but controversial drug, hydroxychloroquine (HCQ), in an effort to provide an objective, scientific and methodologically correct overview of its potential prophylactic role. The advantage of using known drugs is that their toxicity profile is well known and there are fewer commercial interests (e.g., expired patents), thus allowing the scientific community to be freer of constraints. The main disadvantage is that the economic resources are almost always insufficient to promote large multinational clinical trials. In the present study, we reviewed the literature and available data on the prophylactic use of HCQ. We also took an in-depth look at all the published clinical data on the drug and examined ongoing clinical trials (CTs) from the most important CT repositories to identify a supporting rationale for HCQ prophylactic use. Our search revealed a substantial amount of preclinical data but a lack of clinical data, highlighting the need to further assess the translational impact of in vitro data in a clinical setting. We identified 77 CTs using a multiplicity of HCQ schedules, which clearly indicates that we are still far from reaching a standard of care. The majority of the CTs (92%) are randomized and 53% are being conducted in a phase 3 or 2/3 setting. The comparator is placebo or control in 55 (77%) of the randomized studies. Forty-eight (62%) CTs expect to enroll up to 1,000 subjects and 50 (71%) plan to recruit healthcare workers (HCW). With regard to drug schedules, 45 (58.5%) CTs have planned a loading dose, while 18 (23.4%) have not; the loading dose is 800 mg in 19 trials (42.2%), 400 mg in 19 (42.2%), 600 mg in 4 (8.9%) and 1,200 mg in 1 (2.2%). Forty trials include at least one daily schedule, while 19 have at least one weekly schedule. Forty-one (53.2%) will have a treatment duration of more than 30 days. Awaiting further developments that can only derive from the results of these prospective randomized CTs, the take-home message of our review is that a correct methodological approach is the key to understanding whether prophylactic HCQ can really represent an effective strategy in preventing COVID-19.