A systematic review of trial registry entries for randomized clinical trials investigating COVID-19 medical prevention and treatment

Features and results availability of non-commercial Spanish COVID-19 trials: a systematic review of clinical trial registers and corresponding literature

OBJECTIVES

This study aimed to characterize non-commercial Spanish COVID-19 trials and to determine the availability of results. Differences in outcomes according to the interventions assessed (medicines, non-medicines) will also be determined.

METHODS

This systematic review was conducted in March 2024 by searching non-commercial Spanish COVID-19 trials on four registers (EUCTR, Clinical.

TRIALS

gov, ISRCTN, DRKS) and the WHO ICTRP. Phase-1 medicines trials were excluded. Several variables were retrieved from registers. Publication of main trial results were searched on PubMed, Cochrane COVID-19 Study Register, and Google Scholar. Journals' impact factor and articles' citations on Google Scholar were also registered. Results from medicines and non-medicines trials extracted from registers and articles were compared.

RESULTS

A total of 170 trials (57.1% medicines trials) were identified. These 170 trials were randomized (87.1%), masked (41.8%), or multicenter (39.4%); a total of 15,555 participants were enrolled, mostly in small trials (median, n = 88). Only 8.8% (15/170) of trials posted results on the registers; only 47.6% (81/170) of trials had either published results or posted them on registers. Publications accounted for 92.6% (75/81) of these. Articles were published in 56 different journals, had a median impact factor of 4.4 and a median of 10 citations. Most (58.7%, 44/75) described negative results. There were statistically significant differences (p < 0.001) between medicines and non-medicines trials on timely registration and on being multicenter. This was also the case among published trials with respect to negative results of the primary endpoint.

CONCLUSION

Although most trials were randomized, a minority were multicenter, large, or masked. Trial results should be posted on the registers to make them accessible to everyone.

Autoimmunity, a relevant exclusion criterion in the development of mRNA-based compounds: A systematic review of clinical trials registries

BACKGROUND

Messenger RNA (mRNA) -based compounds have been lately developed as one of the most promising treatment alternatives in a wide range of pathologies, especially cancers and infectious diseases.

AIM

To review the current research landscape on mRNA-based compounds, with a focus on the inclusion criteria used for participants with autoimmune diseases and/or under immunosuppressive treatments.

METHODS

We conducted a comprehensive search based on PICO framework specifically formulated, throughout the most important clinical trial registries: WHO International Clinical Trials Registry Platform (ICTRP) portal, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials (CENTRAL), as well as in the Pfizer-BioNTech and Moderna official websites. Data extraction followed the CONSORT checklist, focusing on identifying the specific exclusion criteria for individuals with autoimmune diseases and those undergoing various immunosuppressive treatments, including daily dosages, treatment length, and required cessation periods before enrollment. We performed descriptive and comparative analyses using statistical tests where applicable. This review followed PRISMA guidelines, and the protocol was registered on PROSPERO (CRD42024544811).

RESULTS

Out of 2818 study protocols identified, 608 met the eligibility criteria, the vast majority (96.9 %) focusing on non-replicating RNA. Most targeted were infectious diseases (66.6 %), primarily COVID-19 (51.3 %), followed by cancers (29.1 %), and other conditions (4.3 %). Having an autoimmune disease was used as an exclusion criterion in 60.8 % of trials; higher exclusion rates were observed in studies designed for cancers when compared to those assessing infections or other pathologies (79.1 % vs. 55.3 % vs. 23.1 %, p < 0.001), as well as in those using cell-based when compared to non-cell delivery systems (79.2 % vs. 57.2 %, p < 0.001). Further, participants under immunosuppressive treatments were excluded from 77.5 % of the trials, primarily due to corticosteroid use. There is considerable variability in exclusion criteria related to immunosuppressive treatment length and cessation time prior enrollment, as well as in the daily corticosteroid dosage.

CONCLUSION

To the best of our knowledge, this is the first review to document the ongoing research designed for mRNA-based compounds. This work highlights the underrepresentation of patients with autoimmune diseases and those on immunosuppressive treatments in clinical trials assessing mRNA-based compounds.

Challenges of consolidating evidence collected during a pandemic and lessons for the future

OBJECTIVE

To illustrate the challenges encountered when gathering rapidly synthesized evidence in response to the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

In this article, we describe the challenges encountered when we performed a systematic literature review (SLR) of randomized controlled trials (RCTs) on the efficacy and safety of treatments for severe COVID-19. The methods of the SLR are described in full, to show the context of our objectives. Then we use the results of the SLR to demonstrate the problems of producing synthesized evidence in this setting.

RESULTS

Various challenges were identified during this SLR. These were primarily a result of heterogeneity in the study methodology of eligible studies. Definitions of the patient populations and outcome measurements were highly variable and the majority of studies demonstrated a high risk of bias, preventing quantitative synthesis of the collated evidence.

CONCLUSION

Consolidating evidence from RCTs evaluating COVID-19 interventions was problematic. Guidance is needed for scenarios with high rapid output in primary research.

Overcoming publication and dissemination bias in infectious diseases clinical trials

Non-timely reporting, selective reporting, or non-reporting of clinical trial results are prevalent and serious issues. WHO mandates that summary results be available in registries within 12 months of study completion and published in full text within 24 months. However, only a limited number of clinical trials in infectious diseases, including those done during the COVID-19 pandemic, have their results posted on ClinicalTrials.gov. An analysis of 50 trials of eight antiviral drugs tested against COVID-19 with a completion date of at least 2 years ago revealed that only 18% had their results published in the registry, with 40% not publishing any results. Non-timely and non-reporting practices undermine patient participation and are ethically unacceptable. Strategies should include obligatory reporting of summary results within 12 months in clinical trial registries, with progress towards peer-reviewed publication within 24 months indicated. Timely publication of research papers should be encouraged through an automated flagging mechanism in clinical trial registries that draws attention to the status of results reporting, such as a green tick for trials that have reported summary results within 12 months and a red tick in case of failure to do so. We propose the inclusion of mandatory clinical trial reporting standards in the International Conference on Harmonization Good Clinical Practice guidelines, which should prohibit sponsor contract clauses that restrict reporting (referred to as gag clauses) and require timely reporting of results as part of the ethics committees' clearance process for clinical trial protocols.

Dissemination of Registered COVID-19 Clinical Trials (DIRECCT): a cross-sectional study

BACKGROUND

The results of clinical trials should be completely and rapidly reported during public health emergencies such as COVID-19. This study aimed to examine when, and where, the results of COVID-19 clinical trials were disseminated throughout the first 18 months of the pandemic.

METHODS

Clinical trials for COVID-19 treatment or prevention were identified from the WHO ICTRP database. All interventional trials with a registered completion date ≤ 30 June 2021 were included. Trial results, published as preprints, journal articles, or registry results, were located using automated and manual techniques across PubMed, Google Scholar, Google, EuropePMC, CORD-19, the Cochrane COVID-19 Study Register, and clinical trial registries. Our main analysis reports the rate of dissemination overall and per route, and the time from registered completion to results using Kaplan-Meier methods, with additional subgroup and sensitivity analyses reported.

RESULTS

Overall, 1643 trials with completion dates ranging from 46 to 561 days prior to the start of results searches were included. The cumulative probability of reporting was 12.5% at 3 months from completion, 21.6% at 6 months, and 32.8% at 12 months. Trial results were most commonly disseminated in journals (n = 278 trials, 69.2%); preprints were available for 194 trials (48.3%), 86 (44.3%) of which converted to a full journal article. Trials completed earlier in the pandemic were reported more rapidly than those later in the pandemic, and those involving ivermectin were more rapidly reported than other common interventions. Results were robust to various sensitivity analyses except when considering only trials in a "completed" status on the registry, which substantially increased reporting rates. Poor trial registry data on completion status and dates limits the precision of estimates.

CONCLUSIONS

COVID-19 trials saw marginal increases in reporting rates compared to standard practice; most registered trials failed to meet even the 12-month non-pandemic standard. Preprints were common, complementing journal publication; however, registries were underutilized for rapid reporting. Maintaining registry data enables accurate representation of clinical research; failing to do so undermines these registries' use for public accountability and analysis. Addressing rapid reporting and registry data quality must be emphasized at global, national, and institutional levels.

COVID-19 vaccine registry for pregnant women: policy to control complications of vaccination in pregnant women in 2021-2022

BACKGROUND

Data management related to COVID-19 vaccination in pregnant women is vital to improve the treatment process and to establish preventive programs. Implementing a registry to manage data is an essential part of this process. This study aims to design a national model of the COVID-19 vaccination registry for pregnant women in Iran.

METHODS

The present study is an applied descriptive study conducted in 2021 and 2022 in two stages. In the first stage, the coordinates of the National Registry of COVID-19 vaccination of pregnant women from related references and articles, as well as the comparative study of the National Registry of COVID-19 vaccination of pregnant women in the United States, Canada, and the United Kingdom was done. In the second stage, the preliminary model was designed. The model was validated using the Delphi technique and questionnaire tools and analyzing the data.

RESULTS

The presented national COVID-19 vaccination registry model of pregnant women's main components consist of objectives, data sources, structure, minimum data set, standards, and registry processes, all of which received 100% expert consensus.

CONCLUSION

The vaccination registry of pregnant women has a major role in managing COVID-19 vaccination data of pregnant women and can be one of the Ministry of Health and Medical Education priorities.

The Effects of Demographic, Training, and Specialization Differences of Physicians in COVID-19 Treatment in Turkey

INTRODUCTION

The study aimed to determine how physicians' professional and institutional characteristics affect their treatment approaches for COVID-19 antiviral and supportive treatment, as well as their demographic characteristics and participation in COVID-19 trainings that may influence these orientations.

METHODS

After researching the literature and conducting interviews with the experts, a questionnaire was prepared. The convenience sampling method was used to distribute the questionnaire online to 408 physicians across the nation in January 2021. Exploratory factor analysis was used to verify the research scale, and the Cronbach's Alpha test was used to confirm its reliability. During the data analysis, descriptive and inferential statistical tests were used.

RESULTS

It was observed that the physicians were willing to give COVID-19 patients the antivirals but hesitant to provide and suggest supportive care. The training status for COVID-19 treatment was varied. Female physicians prescribed more antiviral drugs than male physicians, received more training, and scored higher across the scale than male physicians ( p = 0.001). The treatment approaches of physicians varied according to their specializations ( p = 0.002) all over the scale.

CONCLUSION

The publication of current Ministry of Health guidelines on a variety of themes related to COVID-19 treatment, as seen in Turkey, is both beneficial and important. However, because all physicians, regardless of specialty, are affected by current and will be in the future pandemics, it is necessary to design and maintain a continuous training program on pandemics and their management for all physicians.

Estimating the effect of COVID-19 on trial design characteristics: a registered report

There have been reports of poor-quality research during the COVID-19 pandemic. This registered report assessed design characteristics of registered clinical trials for COVID-19 compared to non-COVID-19 trials to empirically explore the design of clinical research during a pandemic and how it compares to research conducted in non-pandemic times. We did a retrospective cohort study with a 1 : 1 ratio of interventional COVID-19 registrations to non-COVID-19 registrations, with four trial design outcomes: use of control arm, randomization, blinding and prospective registration. Logistic regression was used to estimate the odds ratio of investigating COVID-19 versus not COVID-19 and estimate direct and total effects of investigating COVID-19 for each outcome. The primary analysis showed a positive direct and total effect of COVID-19 on the use of control arms and randomization. It showed a negative direct effect of COVID-19 on blinding but no evidence of a total effect. There was no evidence of an effect on prospective registration. Taken together with secondary and sensitivity analyses, our findings are inconclusive but point towards a higher prevalence of key design characteristics in COVID-19 trials versus controls. The findings do not support much existing COVID-19 research quality literature, which generally suggests that COVID-19 led to a reduction in quality. Limitations included some data quality issues, minor deviations from the pre-registered plan and the fact that trial registrations were analysed which may not accurately reflect study design and conduct. Following in-principle acceptance, the approved stage 1 version of this manuscript was pre-registered on the Open Science Framework at https://doi.org/10.17605/OSF.IO/5YAEB. This pre-registration was performed prior to data analysis.

Randomized controlled trials in patients with COVID-19: a systematic review and critical appraisal

OBJECTIVES

This study aimed to describe the prevalence of risks of bias in randomized trials of therapeutic interventions for COVID-19.

METHODS

Systematic review and risk of bias assessment performed by two independent reviewers of a random sample of 40 randomized trials of therapeutic interventions for moderate-severe COVID-19. We used the RoB 2.0 tool to assess the risk of bias, which evaluates bias under five domains as well as an overall assessment of each trial as high or low risk of bias.

RESULTS

Of the 40 included trials, 19 (47%) were at high risk of bias, and this was particularly frequent in trials from low-middle income countries (11/14, 79%). Potential deviations to intended interventions (i.e., control participants accessing experimental treatments) were considered a potential source of bias in some studies (14, 35%), as was the risk due to selective reporting of results (6, 15%). The randomization process was considered at low risk of bias in most studies (34, 95%), as were missing data (36, 90%) and measurement of the outcome (35, 87%).

CONCLUSION

Many randomized trials evaluating COVID-19 interventions are at risk of bias, particularly those conducted in low-middle income countries. Biases are mostly due to deviations from intended interventions and partly due to the selection of reported results. The use of placebo control and publicly available protocol can mitigate many of these risks.

Tranilast as an Adjunctive Therapy in Hospitalized Patients with Severe COVID- 19: A Randomized Controlled Trial

Background

Tranilast is a potential NLRP3 inflammasome inhibitor that may relieve progressive inflammation due to COVID-19.

Aim of the study

To evaluate the therapeutic effects of Tranilast in combination with antiviral drugs in non-ICU-admitted hospitalized patients with COVID-19.

Methods

This study was an open-label clinical trial that included 72 hospitals admitted patients with severe COVID-19 at Razi Hospital, Ahvaz, Iran, from July 2020–August 2020. These patients were randomly assigned in a 1:1 ratio to control (30) and intervention groups (30). Patients in the control group received antiviral therapy, while patients in the intervention group received Tranilast (300 mg daily) in addition to the antiviral drugs for Seven days. The collected data, including the expression of inflammatory cytokine, laboratory tests, and clinical findings, was used for intragroup comparisons.

Results

The intervention group showed significantly lower levels of NLR (p = 0.001), q-CRP (p = 0.002), IL-1 (p = 0.001), TNF (p = 0.001), and LDH (p = 0.046) in comparison with the control group. The effect of intervention was significant in increasing the o2 saturation (F = 7.72, p = 0.007). Long hospitalization (four days or above) was 36.6% in the Tranilast and 66.6% in the control group (RR = 0.58; 95% CI: 0.38–1.06, p = 0.045). In the Tranilst and control groups, one and four deaths or hospitalization in ICU were observed respectively (RR = 0.31; 95% CI: 0.03–2.88, p = 0.20).

Conclusions

Tranilast might be used as an effective and safe adjuvant therapy and enhance the antiviral therapy's efficacy for managing patients with COVID-19.

Hydroxychloroquine for prophylaxis of COVID-19 in health workers: A randomized clinical trial

INTRODUCTION

Health care workers are at high risk of being infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our aim is to evaluate the efficacy and safety of hydroxychloroquine (HCQ) for prophylaxis of coronavirus disease 19 (COVID-19) in health personnel exposed to patients infected by SARS-CoV-2.

METHODS

Double-blind randomized, placebo-controlled single center clinical trial. Included subjects were health care workers caring for severe COVID-19 patients. Main outcome was time to symptomatic SARS-CoV-2 infection.

RESULTS

127 subjects with a confirmed baseline negative RT-PCR SARS-CoV2 test were included in the trial. 62 assigned to HCQ and 65 to placebo. One subject (1.6%) in the HCQ group and 6 (9.2%) subjects in the placebo group developed COVID-19 (Log-Rank test p = 0.07). No severe COVID-19 cases were observed. The study was suspended because of a refusal to participate and losses to follow up after several trials reported lack of effectiveness of hydroxychloroquine in hospitalized patients with COVID-19.

CONCLUSION

The effect size of hydroxychloroquine was higher than placebo for COVID-19 symptomatic infection in health personnel, although this was not statistically significant. The trial is underpowered due to the failure to complete the estimated sample size.

Results availability and timeliness of registered COVID-19 clinical trials: interim cross-sectional results from the DIRECCT study

OBJECTIVE

To examine how and when the results of COVID-19 clinical trials are disseminated.

DESIGN

Cross-sectional study.

SETTING

The COVID-19 clinical trial landscape.

PARTICIPANTS

285 registered interventional clinical trials for the treatment and prevention of COVID-19 completed by 30 June 2020.

MAIN OUTCOME MEASURES

Overall reporting and reporting by dissemination route (ie, by journal article, preprint or results on a registry); time to reporting by dissemination route.

RESULTS

Following automated and manual searches of the COVID-19 literature, we located 41 trials (14%) with results spread across 47 individual results publications published by 15 August 2020. The most common dissemination route was preprints (n=25) followed by journal articles (n=18), and results on a registry (n=2). Of these, four trials were available as both a preprint and journal publication. The cumulative incidence of any reporting surpassed 20% at 119 days from completion. Sensitivity analyses using alternate dates and definitions of results did not appreciably change the reporting percentage. Expanding minimum follow-up time to 3 months increased the overall reporting percentage to 19%.

CONCLUSION

COVID-19 trials completed during the first 6 months of the pandemic did not consistently yield rapid results in the literature or on clinical trial registries. Our findings suggest that the COVID-19 response may be seeing quicker results disclosure compared with non-emergency conditions. Issues with the reliability and timeliness of trial registration data may impact our estimates. Ensuring registry data are accurate should be a priority for the research community during a pandemic. Data collection is underway for the next phase of the DIssemination of REgistered COVID-19 Clinical Trials study expanding both our trial population and follow-up time.

A Review on the Role of Stem Cells against SARS-CoV-2 in Children and Pregnant Women

Since the COVID-19 outbreak was acknowledged by the WHO on 30 January 2020, much research has been conducted to unveil various features of the responsible SARS-CoV-2 virus. Different rates of contagion in adults, children, and pregnant women may guide us to understand the underlying infection conditions of COVID-19. In this study, we first provide a review of recent reports of COVID-19 clinical outcomes in children and pregnant women. We then suggest a mechanism that explains the curious case of COVID-19 in children/pregnant women. The unique stem cell molecular signature, as well as the very low expression of angiotensin-converting enzyme 2 and the lower ACE/ACE2 ratio in stem cells of children/pregnant women compared to adults might be the cause of milder symptoms of COVID-19 in them. This study provides the main molecular keys on how stem cells can function properly and exert their immunomodulatory and regenerative effects in COVID-19-infected children/pregnant women, while failing to replicate their role in adults. This can lay the groundwork for both predicting the pattern of spread and severity of the symptoms in a population and designing novel stem cell-based treatment and prevention strategies for COVID-19.

Challenges and Lessons Learned From COVID-19 Trials: Should We Be Doing Clinical Trials Differently?

The COVID-19 crisis led to a flurry of clinical trials activity. The COVID-evidence database shows 2814 COVID-19 randomized trials registered as of February 16, 2021. Most were small (only 18% have a planned sample size > 500) and the rare completed ones have not provided published results promptly (only 283 trial publications as of February 2021). Small randomized trials and observational, nonrandomized analyses have not had a successful track record and have generated misleading expectations. Different large trials on the same intervention have generally been far more efficient in producing timely and consistent evidence. The rapid generation of evidence and accelerated dissemination of results have led to new challenges for systematic reviews and meta-analyses (eg, rapid, living, and scoping reviews). Pressure to regulatory agencies has also mounted with massive emergency authorizations, but some of them have had to be revoked. Pandemic circumstances have disrupted the way trials are conducted; therefore, new methods have been developed and adopted more widely to facilitate recruitment, consent, and overall trial conduct. On the basis of the COVID-19 experience and its challenges, planning of several large, efficient trials, and wider use of adaptive designs might change the future of clinical research. Pragmatism, integration in clinical care, efficient administration, promotion of collaborative structures, and enhanced integration of existing data and facilities might be several of the legacies of COVID-19 on future randomized trials.

Management of COVID-19 in patients with seizures: Mechanisms of action of potential COVID-19 drug treatments and consideration for potential drug-drug interactions with anti-seizure medications

In regard to the global pandemic of COVID-19, it seems that persons with epilepsy (PWE) are not more vulnerable to get infected by SARS-CoV-2, nor are they more susceptible to a critical course of the disease. However, management of acute seizures in patients with COVID-19 as well as management of PWE and COVID-19 needs to consider potential drug-drug interactions between antiseizure drugs and candidate drugs currently assessed as therapeutic options for COVID-19. Repurposing of several licensed and investigational drugs is discussed for therapeutic management of COVID-19. While for none of these approaches, efficacy and tolerability has been confirmed yet in sufficiently powered and controlled clinical studies, testing is ongoing with multiple clinical trials worldwide. Here, we have summarized the possible mechanisms of action of drugs currently considered as potential therapeutic options for COVID-19 management along with possible and confirmed drug-drug interactions that should be considered for a combination of antiseizure drugs and COVID-19 candidate drugs. Our review suggests that potential drug-drug interactions should be taken into account with drugs such as chloroquine/hydroxychloroquine and lopinavir/ritonavir while remdesivir and tocilizumab may be less prone to clinically relevant interactions with ASMs.

The efficacy and safety of Favipiravir in treatment of COVID-19: a systematic review and meta-analysis of clinical trials

The novel coronavirus outbreak began in late December 2019 and rapidly spread worldwide, critically impacting public health systems. A number of already approved and marketed drugs are being tested for repurposing, including Favipiravir. We aim to investigate the efficacy and safety of Favipiravir in treatment of COVID-19 patients through a systematic review and meta-analysis. This systematic review and meta-analysis were reported in accordance with the PRISMA statement. We registered the protocol in the PROSPERO (CRD42020180032). All clinical trials which addressed the safety and efficacy of Favipiravir in comparison to other control groups for treatment of patients with confirmed infection with SARS-CoV2 were included. We searched electronic databases including LitCovid/PubMed, Scopus, Web of Sciences, Cochrane, and Scientific Information Database up to 31 December 2020. We assessed the risk of bias of the included studies using Cochrane Collaboration criteria. All analyses were performed using the Comprehensive Meta-Analysis software version 2, and the risk ratio index was calculated. Egger and Begg test was used for assessing publication bias. Nine studies were included in our meta-analysis. The results of the meta-analysis revealed a significant clinical improvement in the Favipiravir group versus the control group during seven days after hospitalization (RR = 1.24, 95% CI: 1.09-1.41; P = 0.001). Viral clearance was more in 14 days after hospitalization in Favipiravir group than control group, but this finding marginally not significant (RR = 1.11, 95% CI: 0.98-1.25; P = 0.094). Requiring supplemental oxygen therapy in the Favipiravir group was 7% less than the control group, (RR = 0.93, 95% CI: 0.67-1.28; P = 0.664). Transferred to ICU and adverse events were not statistically different between two groups. The mortality rate in the Favipiravir group was approximately 30% less than the control group, but this finding not statistically significant. Favipiravir possibly exerted no significant beneficial effect in the term of mortality in the general group of patients with mild to moderate COVID-19. We should consider that perhaps the use of antiviral once the patient has symptoms is too late and this would explain their low efficacy in the clinical setting.

Predicting COVID-19-Comorbidity Pathway Crosstalk-Based Targets and Drugs: Towards Personalized COVID-19 Management

It is well established that pre-existing comorbid conditions such as hypertension, diabetes, obesity, cardiovascular diseases (CVDs), chronic kidney diseases (CKDs), cancers, and chronic obstructive pulmonary disease (COPD) are associated with increased severity and fatality of COVID-19. The increased death from COVID-19 is due to the unavailability of a gold standard therapeutic and, more importantly, the lack of understanding of how the comorbid conditions and COVID-19 interact at the molecular level, so that personalized management strategies can be adopted. Here, using multi-omics data sets and bioinformatics strategy, we identified the pathway crosstalk between COVID-19 and diabetes, hypertension, CVDs, CKDs, and cancers. Further, shared pathways and hub gene-based targets for COVID-19 and its associated specific and combination of comorbid conditions are also predicted towards developing personalized management strategies. The approved drugs for most of these identified targets are also provided towards drug repurposing. Literature supports the involvement of our identified shared pathways in pathogenesis of COVID-19 and development of the specific comorbid condition of interest. Similarly, shared pathways- and hub gene-based targets are also found to have potential implementations in managing COVID-19 patients. However, the identified targets and drugs need further careful evaluation for their repurposing towards personalized treatment of COVID-19 cases having pre-existing specific comorbid conditions we have considered in this analysis. The method applied here may also be helpful in identifying common pathway components and targets in other disease-disease interactions too.

Tuberculosis vaccine BCG: the magical effect of the old vaccine in the fight against the COVID-19 pandemic

Bacillus Calmette-Guérin (BCG) is a live attenuated M. bovis vaccine that was developed about 100 years ago by Albert Calmette and Camille Guérin. Many countries have been using the vaccine for decades against tuberculosis (TB). The World Health Organization (WHO) recommends a single dose of BCG for infants in TB endemic as well as leprosy high risk countries, and globally almost 130 million infants are vaccinated yearly. The role of BCG is well known in reducing neonatal and childhood death rates. Epidemiological and retrospective cross-sectional studies demonstrated that the BCG vaccination protects the children against respiratory tract infections and lowers the risk of malaria in children. In addition, BCG enhances IFN-γ and IL-10 levels, thus providing immunity against respiratory tract infection even in elderly people. The BCG is also known to provide nonspecific innate immunity against viruses and parasites, through an innate immune mechanism termed ‘trained immunity’ and is defined as the immunological recall of the innate immune system by epigenetic reprogramming. Based on these studies it is suggested that the BCG has the potential to act as a protective agent against COVID-19. Further proven safety records of BCG in humans, its adjuvant activity and low-cost manufacturing make it an attractive option to stop the pandemic and reduce the COVID-19 related mortality. In this review we discuss the heterologous effects of BCG, induction of trained immunity and its implication in development of a potential vaccine against COVID-19 pandemic.

Mesenchymal Stem Cells and COVID-19: Cure, Prevention, and Vaccination

COVID-19 disease has been a global health problem since late 2019. There are many concerns about the rapid spread of this disease, and yet, there is no approved treatment for COVID-19. Several biological interventions have been under study recently to investigate efficient treatment for this viral disease. Besides, many efforts have been made to find a safe way to prevent and vaccinate people against COVID-19 disease. In severe cases, patients suffer from acute respiratory distress syndrome usually associated with an increased level of inflammatory cytokines, called a cytokine storm. It seems that reequilibrating the hyperinflammatory response of the host immune system and regeneration of damaged cells could be the main way to manage the disease. Mesenchymal stem cells (MSCs) have been recently under investigation in this regard, and the achieved clinical outcomes show promising evidence for stem cell-based therapy of COVID-19. MSCs are known for their potential for immunomodulation, defense against virus infection, and tissue regeneration. MSCs are a newly emerged platform for designing vaccines and show promising evidence in this area. In the present study, we provided a thorough research study on the most recent clinical studies based on stem cells in the treatment of COVID-19 while introducing stem cell exclusivities for use as an immune disorder or lung cell therapy and its potential application for protection and vaccination against COVID-19.

Prophylaxis for COVID-19: a systematic review

BACKGROUND

While the landscape of vaccine and treatment candidates against the novel coronavirus disease 2019 (COVID-19) has been reviewed systematically, prophylactic candidates remain unexplored.

OBJECTIVES

To map pre- and postexposure prophylactic (PrEP and PEP) candidate for COVID-19.

DATA SOURCES

PubMed/Medline, Embase, International Committee of Medical Journal Editors and International Clinical Trials Registry Platform clinical trial registries and medRxiv.

STUDY ELIGIBILITY CRITERIA AND PARTICIPANTS

All studies in humans or animals and randomized controlled trials (RCTs) in humans reporting primary data on prophylactic candidates against COVID-19, excluding studies focused on key populations.

INTERVENTIONS

PrEP and PEP candidate for COVID-19.

METHODS

Systematic review and qualitative synthesis of COVID-19 PrEP and PEP studies and RCTs complemented by search of medRxiv and PubMed and Embase for studies reporting RCT outcomes since systematic review search completion.

RESULTS

We identified 13 studies (from 2119 database records) and 117 RCTs (from 5565 RCTs listed in the registries) that met the inclusion criteria. Non-RCT studies reported on cross-sectional studies using hydroxychloroquine (HCQ) in humans (n = 2) or reported on animal studies (n = 7), most of which used antibodies. All five completed RCTs focused on the use of HCQ as either PrEP or PEP, and these and the cross-sectional studies reported no prophylactic effect. The majority of ongoing RCTs evaluated HCQ or other existing candidates including non-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines, anti(retro)virals or use of vitamins and supplements.

CONCLUSIONS

The key message from completed studies and RCTs seems to be that HCQ does not work. There is little evidence regarding other compounds, with all RCTs using candidates other than HCQ still ongoing. It remains to be seen if the portfolio of existing molecules being evaluated in RCTs will identify successful prophylaxis against COVID-19 or if there is a need for the development of new candidates.

SARS-CoV-2 infection: molecular mechanisms of severe outcomes to suggest therapeutics

Introduction:The year 2020 was defined by the 29,903 base pairs of RNA that codes for the SARS-CoV-2 genome. SARS-CoV-2 infects humans to cause COVID-19, spreading from patient-to-patient yet impacts patients very divergently.Areas covered: Within this review, we address the known molecular mechanisms and supporting data for COVID-19 clinical course and pathology, clinical risk factors and molecular signatures, therapeutics of severe COVID-19, and reinfection/vaccination. Literature and published datasets were reviewed using PubMed, Google Scholar, and NCBI SRA tools. The combination of exaggerated cytokine signaling, pneumonia, NETosis, pyroptosis, thrombocytopathy, endotheliopathy, multiple organ dysfunction syndrome (MODS), and acute respiratory distress syndrome (ARDS) create a positive feedback loop of severe damage in patients with COVID-19 that impacts the entire body and may persist for months following infection. Understanding the molecular pathways of severe COVID-19 opens the door for novel therapeutic design. We summarize the current insights into pathology, risk factors, secondary infections, genetics, omics, and drugs being tested to treat severe COVID-19.Expert opinion: A growing level of support suggests the need for stronger integration of biomarkers and precision medicine to guide treatment strategies of severe COVID-19, where each patient has unique outcomes and thus require guided treatment.

Systemic Inflammatory Index Is a Novel Predictor of Intubation Requirement and Mortality after SARS-CoV-2 Infection

Coronavirus disease 2019 (COVID-19), with an increasing number of deaths worldwide, has created a tragic global health and economic emergency. The disease, caused by severe acute respiratory syndrome coronavirus 2019 (SARS-CoV-19), is a multi-system inflammatory disease with many of COVID-19-positive patients requiring intensive medical care due to multi-organ failures. Biomarkers to reliably predict the patient's clinical cause of the virus infection, ideally, to be applied in point of care testing or through routine diagnostic approaches, are highly needed. We aimed to probe if routinely assessed clinical lab values can predict the severity of the COVID-19 course. Therefore, we have retrospectively analyzed on admission laboratory findings in 224 consecutive patients from four hospitals and show that systemic immune inflammation index (SII) is a potent marker for predicting the requirement for invasive ventilator support and for worse clinical outcome of the infected patient. Patients' survival and severity of SARS-CoV-2 infection could reliably be predicted at admission by calculating the systemic inflammatory index of individual blood values. We advocate this approach to be a feasible and easy-to-implement assay that may be particularly useful to improve patient management during high influx crisis. We believe with this work to contribute to improving infrastructure availability and case management associated with COVID-19 pandemic hurdles.

Epidemiology, clinical characteristics and treatment of critically ill patients with COVID-19): a protocol for a living systematic review

INTRODUCTION

In December 2019, the first cases of COVID-19 associated with SARS-CoV-2 viral infection were described in Wuhan, Hubei Province, China. Since then, it has spread rapidly affecting 188 countries and was declared a pandemic by the WHO on 11 March 2020. Preliminary reports suggest up to 30% of patients require intensive care unit (ICU) admission and case fatality rate estimate is 2.3%-7.2%. The primary reason for ICU admission is hypoxaemic respiratory failure, while factors associated with ICU admission include increased age, presence of comorbidities and cytokine storm. Case series and retrospective trials initially assessed proposed treatments with randomised controlled trials now reporting early outcomes. We conduct a systematic review and meta-analysis to identify epidemiological factors, treatments and complications that predict mortality among critically ill patients with COVID-19.

METHODS AND ANALYSIS

Our comprehensive search strategy was developed in consultation with a research librarian. We will search electronic databases: Ovid Medline, Ovid Embase, Ovid Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Wiley Cochrane Library. The search strategy combines concepts from COVID-19, validated COVID-19 search filters and geographical locations of large outbreaks. Citation screening, selection, quality assessment and data abstraction will be performed in duplicate. Clinically homogenous epidemiological characteristics, interventions and complications will be pooled in statistical meta-analysis. Within the framework of a living systematic review, the search and data analysis will be updated every 6 months.

ETHICS AND DISSEMINATION

Our systematic review will synthesise literature on risk factors and interventions associated with mortality in critically ill patients with COVID-19. Results will be presented at national and international conferences and submitted for peer-reviewed publication. The pooled analysis can provide guidance to inform clinical guidelines for care of critically ill patients with COVID-19. Iterative updates will be made public through open access. Research ethics approval is not required.

PROSPERO REGISTRATION NUMBER

CRD42020176672.

Ten principles for generating accessible and useable COVID-19 environmental science and a fit-for-purpose evidence base

1. The 'anthropause', a period of unusually reduced human activity and mobility due to COVID-19 restrictions, has serendipitously opened up unique opportunities for research on how human activities impact the environment. 2. In the field of health, COVID-19 research has led to concerns about the quality of research papers and the underlying research and publication processes due to accelerated peer review and publication schedules, increases in pre-prints and retractions. 3. In the field of environmental science, framing the pandemic and associated global lockdowns as an unplanned global human confinement experiment with urgency should raise the same concerns about the rigorousness and integrity of the scientific process. Furthermore, the recognition of an 'infodemic', an unprecedented explosion of research, risks research waste and duplication of effort, although how information is used is as important as the quality of evidence. This highlights the need for an evidence base that is easy to find and use - that is discoverable, curated, synthesizable, synthesized. 4. We put forward a list of 10 key principles to support the establishment of a reproducible, replicable, robust, rigorous, timely and synthesizable COVID-19 environmental evidence base that avoids research waste and is resilient to the pressures to publish urgently. These principles focus on engaging relevant actors (e.g. local communities, rightsholders) in research design and production, statistical power, collaborations, evidence synthesis, research registries and protocols, open science and transparency, data hygiene (cleanliness) and integrity, peer review transparency, standardized keywords and controlled vocabularies.

COVID-19 Clinical Trials Registered Worldwide for Drug Intervention: An Overview and Characteristic Analysis

OBJECTIVE

This study aims to comprehensively evaluate the characteristics of clinical drug trials to facilitate the collection of evidence for COVID-19 drug treatments.

METHODS

A retrospective analysis of 910 trials retrieved on August 7, 2020.

RESULTS

A total of 910 registered clinical trials with at least one drug intervention were evaluated. The number of registrations (32.4%, 295) from the United States accounted for nearly one-third of the total and far exceeded that of other countries individually. Furthermore, the peak number of trials were registered in April (34.3%, 312). Over half of the trials (51.2%, 466) are in the recruitment phase, and only 4.2% (38) of the trials have been completed. The median (interquartile range) estimated enrollment is 127 (59, 365). In 39% (355) of trials, the estimated enrollment is less than 100 participants. A total of 94.5% (790) of the trials use randomization in the allocation, 82.7% (753) use a parallel intervention mode, and 52.2% (475) use masking. A total of 287 drug names have been standardized and mapped. "Hydroxychloroquine" is the leading drug among the registered trials (7.47%, 68). Among the main countries contributing to investigations on "hydroxychloroquine", the United States ranks first with 36.76% (25) of the trials.

CONCLUSION

The designs of COVID-19 clinical drug trials have greatly improved in terms of the implementation of randomization and, particularly, blinding methods. In terms of drug reuse, the number of drug types has greatly increased, and hundreds of drugs have been used for efficacy screening. The emergence of large-sample registration trials is expected to address the uncertainty regarding the current clinical efficacy of some drugs.

Predictors of in-hospital COVID-19 mortality: A comprehensive systematic review and meta-analysis exploring differences by age, sex and health conditions

OBJECTIVE

Risk factors for in-hospital mortality in confirmed COVID-19 patients have been summarized in numerous meta-analyses, but it is still unclear whether they vary according to the age, sex and health conditions of the studied populations. This study explored these variables as potential mortality predictors.

METHODS

A systematic review was conducted by searching the MEDLINE, Scopus, and Web of Science databases of studies available through July 27, 2020. The pooled risk was estimated with the odds ratio (p-OR) or effect size (p-ES) obtained through random-effects meta-analyses. Subgroup analyses and meta-regression were applied to explore differences by age, sex and health conditions. The MOOSE guidelines were strictly followed.

RESULTS

The meta-analysis included 60 studies, with a total of 51,225 patients (12,458 [24.3%] deaths) from hospitals in 13 countries. A higher in-hospital mortality risk was found for dyspnoea (p-OR = 2.5), smoking (p-OR = 1.6) and several comorbidities (p-OR range: 1.8 to 4.7) and laboratory parameters (p-ES range: 0.3 to -2.6). Age was the main source of heterogeneity, followed by sex and health condition. The following predictors were more markedly associated with mortality in studies with patients with a mean age ≤60 years: dyspnoea (p-OR = 4.3), smoking (p-OR = 2.8), kidney disease (p-OR = 3.8), hypertension (p-OR = 3.7), malignancy (p-OR = 3.7), diabetes (p-OR = 3.2), pulmonary disease (p-OR = 3.1), decreased platelet count (p-ES = -1.7), decreased haemoglobin concentration (p-ES = -0.6), increased creatinine (p-ES = 2.4), increased interleukin-6 (p-ES = 2.4) and increased cardiac troponin I (p-ES = 0.7). On the other hand, in addition to comorbidities, the most important mortality predictors in studies with older patients were albumin (p-ES = -3.1), total bilirubin (p-ES = 0.7), AST (p-ES = 1.8), ALT (p-ES = 0.4), urea nitrogen (p-ES), C-reactive protein (p-ES = 2.7), LDH (p-ES = 2.4) and ferritin (p-ES = 1.7). Obesity was associated with increased mortality only in studies with fewer chronic or critical patients (p-OR = 1.8).

CONCLUSION

The prognostic effect of clinical conditions on COVID-19 mortality vary substantially according to the mean age of patients.

PROSPERO REGISTRATION NUMBER

CRD42020176595.