Efficacy and safety of therapeutic vs. prophylactic bemiparin in noncritically ill patients with COVID-19 pneumonia

American Society of Hematology living guidelines on use of anticoagulation for thromboprophylaxis for patients with COVID-19: executive summary

BACKGROUND

COVID-19-related critical and acute illness is associated with an increased risk of venous thromboembolism (VTE). These evidence-based recommendations of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about using anticoagulation for thromboprophylaxis for patients with COVID-19-related critical illness; patients with COVID-19-related acute illness; and those being discharged from the hospital, who do not have suspected or confirmed VTE.

METHODS

ASH formed a multidisciplinary panel, including patient representatives. The Michael G. DeGroote Cochrane Canada and MacGRADE Centres at McMaster University supported guideline development, including performing systematic reviews (up to June 2023). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to assess certainty in the evidence and make recommendations.

RESULTS

This is an executive summary of 3 updated recommendations that have been published, which concludes the living phase of the guidelines. For patients with COVID-19-related critical illness, the panel issued conditional recommendations suggesting (a) prophylactic-intensity over therapeutic-intensity anticoagulation and (b) prophylactic-intensity over intermediate-intensity anticoagulation. For patients with COVID-19-related acute illness, conditional recommendations were suggested (a) prophylactic-intensity over intermediate-intensity anticoagulation, and (b) therapeutic-intensity over prophylactic-intensity anticoagulation. The panel issued a conditional recommendation suggesting against the use of postdischarge anticoagulant thromboprophylaxis.

CONCLUSIONS

These conditional recommendations were made based on low or very low certainty in the evidence, underscoring the need for additional, high-quality, randomized controlled trials for patients with COVID-19.

Therapeutic Versus Non-Therapeutic Dose Anticoagulation in COVID-19 Infection: A Systematic Review and Meta-analysis of Randomised Controlled Trials

Background

Abnormal coagulation and thrombotic complications prompted many guidelines to recommend thromboprophylaxis for patients hospitalised with COVID-19, but the dose required for prophylaxis remains unclear. This systematic review (SR) analyses the safety and efficacy of therapeutic dose anticoagulation (TDA) versus non-therapeutic dose anticoagulation (NDA) in COVID-19 patients.

Methods

According to the Cochrane Handbook of Systematic Review of Interventions, we performed an SR. The protocol is registered in Prospero (CRD42021269197, date 12 August 2021).

Results

In this SR of 18 studies, TDA was shown to reduce all-cause mortality (risk ratio [RR] 0.83; 95% confidence interval [95% CI] 0.70, 0.99) in COVID-19 infection. TDA also reduced thrombosis (RR 0.55; 95% CI 0.48, 0.72) but increased major bleeding (RR 1.87; 95% CI 1.29, 2.69). A stratified analysis according to severity revealed that, in non-critical patients, TDA resulted in mortality benefit (RR 0.79; 95% CI 0.67, 0.94). In critical patients, TDA did not affect all-cause mortality (RR 1.03; 95% CI 0.89, 1.18) but reduced thrombosis (RR 0.65; 95% CI 0.48, 0.86) and increased major bleeding (RR 1.85; 95% CI 1.06, 3.23).

Conclusion

TDA significantly reduced all-cause mortality and thrombosis in non-critical COVID-19 patients at the expense of increased major bleeding. In critical COVID-19, this mortality benefit was not observed.

Real-world evidence with a retrospective cohort of 15,968 COVID-19 hospitalized patients suggests 21 new effective treatments

PURPOSE

Despite the extensive vaccination campaigns in many countries, COVID-19 is still a major worldwide health problem because of its associated morbidity and mortality. Therefore, finding efficient treatments as fast as possible is a pressing need. Drug repurposing constitutes a convenient alternative when the need for new drugs in an unexpected medical scenario is urgent, as is the case with COVID-19.

METHODS

Using data from a central registry of electronic health records (the Andalusian Population Health Database), the effect of prior consumption of drugs for other indications previous to the hospitalization with respect to patient outcomes, including survival and lymphocyte progression, was studied on a retrospective cohort of 15,968 individuals, comprising all COVID-19 patients hospitalized in Andalusia between January and November 2020.

RESULTS

Covariate-adjusted hazard ratios and analysis of lymphocyte progression curves support a significant association between consumption of 21 different drugs and better patient survival. Contrarily, one drug, furosemide, displayed a significant increase in patient mortality.

CONCLUSIONS

In this study we have taken advantage of the availability of a regional clinical database to study the effect of drugs, which patients were taking for other indications, on their survival. The large size of the database allowed us to control covariates effectively.

The optimal anticoagulation strategy for COVID-19, prophylactic or therapeutic?: a meta-analysis, trial sequential analysis, and meta-regression of more than 27,000 participants

Background

Anticoagulants are promising regimens for treating coronavirus disease 2019 (COVID-19). However, whether prophylactic or intermediate-to-therapeutic dosage is optimal remains under active discussion.

Methods

We comprehensively searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, ClinicalTrials, and MedRxiv databases on April 26, 2022. Two independent researchers conducted literature selection and data extraction separately according to predetermined criteria. Notably, this is the first meta-analysis on COVID-19, taking serious consideration regarding the dosage overlap between the 2 comparison groups of prophylactic anticoagulation (PA) and intermediate-to-therapeutic anticoagulation (I-TA).

Results

We included 11 randomized controlled trials (RCTs) and 36 cohort studies with 27,051 COVID-19 patients. By analyzing all the RCTs, there was no significant difference in mortality between the PA and I-TA groups, which was further confirmed by trial sequential analysis (TSA) (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.71–1.22; P = 0.61; TSA adjusted CI: 0.71–1.26). The rate of major bleeding was remarkably higher in the I-TA group than in the PA group, despite adjusting for TSA (OR: 1.73; 95% CI: 1.15–2.60; P = 0.009; TSA adjusted CI: 1.09–2.58). RCTs have supported the beneficial effect of I-TA in reducing thrombotic events. After including all studies, mortality in the I-TA group was significantly higher than in the PA group (OR: 1.38; 95% CI: 1.15–1.66; P = 0.0005). The rate of major bleeding was similar to the analysis from RCTs (OR: 2.24; 95% CI: 1.86–2.69; P < 0.00001). There was no distinct difference in the rate of thrombotic events between the 2 regimen groups. In addition, in both critical and noncritical subgroups, I-TA failed to reduce mortality but increased major bleeding rate compared with PA, as shown in meta-analysis of all studies, as well as RCTs only. Meta-regression of all studies suggested that there was no relationship between the treatment effect and the overall risk of mortality or major bleeding (P = 0.14, P = 0.09, respectively).

Conclusion

I-TA is not superior to PA for treating COVID-19 because it fails to lower the mortality rate but increases the major bleeding rate in both critical and noncritical patients.