Latest advances in the reversal strategies for direct oral anticoagulants.

BACKGROUND: Since the late 2000s, Europe has granted approval for various thrombotic risk-related uses of direct oral anticoagulants (DOACs). Unlike traditional anticoagulants, DOACs do not necessitate routine coagulation monitoring. Nevertheless, clinical practice often encounters bleeding events associated with these medications, making the need for effective reversal strategies evident. OBJECTIVES: The study aims to take stock of current reversal strategies for DOACs, with a particular emphasis on the latest compounds that have been developed or are currently under development. METHODS: For obtaining information regarding the ongoing reversal strategies and the compounds under development, we referred to ClinicalTrials website, PubMed, and Google Scholar. RESULTS: In 2024, two specific antidotes to DOACs have already received approval when reversal of anticoagulation is needed owing to life-threatening or uncontrolled bleeding: idarucizumab that reverses the effects of dabigatran, and andexanet alfa, designed to counteract activated factor X inhibitors such as apixaban and rivaroxaban. Furthermore, ciraparantag, a potential universal reversal agent, is currently in advanced stages of clinical development. Concerns remain regarding the safety of specific reversal agents, especially concerning the risk of thrombosis. Additionally, the cost of these antidotes remains high. Consequently, nonspecific strategies to counteract anticoagulant medications, including activated charcoal, hemodialysis, and concentrates of coagulation factors, still have utility. CONCLUSION: With the validation of specific and nonspecific antidotes, DOACs could supplant traditional oral anticoagulants. This progress represents a significant advancement in anticoagulation therapy. However, ongoing research is crucial to address remaining safety concerns of the specific reversion agents of DOACs in clinical practice.

Data Monitoring Committees and clinical trials: From scientific justification to organisation.

Clinical trials often last several months or even several years. As the trial progresses, it can be tempting to find out whether the data obtained already answers the question posed at the start of the trial in order to stop inclusions or monitoring earlier. However, knowing and taking into account interim results can sometimes compromise the integrity of the results, which is counterproductive. To minimise this risk and ensure that the treatments are assessed reliably, safety and/or efficacy criteria are monitored during the study by a Data Monitoring Committee. After receiving the results confidentially, the Data Monitoring Committee assesses the benefit/risk ratio of the study treatment and recommends that the trial be continued, modified or terminated. Data Monitoring Committee members issuing these recommendations have an important responsibility: a hasty decision to end the trial may lead to inconclusive results unable to answer the initial question and, inversely, delaying the decision to end the trial may expose the subjects to potentially ineffective or even harmful interventions. The Data Monitoring Committee's task is therefore particularly complex. With this in mind, the round table discussion at the Giens workshops was a chance to review the scientific justification for creating Data Monitoring Committees and to recall the need for their members to receive comprehensive training on the complexities of multiple analyses, confidentiality requirements applying to the results and the need for them to be aware that recommendations to end a trial must be based on data that is robust enough to assess the benefit/risk ratio of the treatment studied.

Enoxaparin versus Placebo to Prevent Symptomatic Venous Thromboembolism in Hospitalized Older Adult Medical Patients.

BACKGROUND: Admission to the hospital is a major risk factor for the development of venous thromboembolism (VTE). Whether thromboprophylaxis with low-molecular-weight heparin prevents symptomatic VTE in medically ill, hospitalized older adults remains debated. METHODS: In a prospective, randomized, placebo-controlled, double-blind, multicenter trial, older adults (>70 years of age) hospitalized for acute medical conditions were randomly assigned to receive 40 mg a day of low-molecular-weight heparin (enoxaparin) or placebo for 6 to 14 days. The primary efficacy outcome was the cumulative incidence of symptomatic VTE (distal or proximal deep vein thrombosis, fatal or nonfatal pulmonary embolism) at 30 days. The primary safety outcome was major bleeding. Secondary outcomes included efficacy and safety outcomes at 90 days. RESULTS: The trial was prematurely discontinued in September 2020, 5 years after enrollment began, because of drug supply issues. By the time of trial discontinuation, 2559 patients had been randomly assigned at 47 centers. Median age was 82 years and 60% of patients were female. In the intention-to-treat population, the primary efficacy outcome occurred in 22 out of 1278 (cumulative incidence, 1.8%) patients in the enoxaparin group and in 27 out of 1263 (cumulative incidence, 2.2%) patients in the placebo group (cumulative incidence difference, −0.4 percentage points; 95% confidence interval, −1.5 to 0.7), with no significant difference in time to VTE (P=0.46). The incidence of major bleeding was 0.9% in the enoxaparin group and 1.0% in the placebo group. At 90 days there were 14 symptomatic pulmonary emboli in the enoxaparin group and 25 in the placebo group; all 39 pulmonary embolism events resulted in hospital readmission and/or death, with 5 deaths from pulmonary embolism in the enoxaparin group and 11 deaths in the placebo group. CONCLUSIONS: This trial of thromboprophylaxis in medically ill, hospitalized older adults did not demonstrate that enoxaparin reduced the risk of symptomatic VTE after 1 month. Because the trial was prematurely discontinued, larger trials are needed to definitively address this question. (Funded by the French Ministry of Health Programme Hospitalier de Recherche Clinique, grant number PHRC-N-13-0283; ClinicalTrials.gov number, NCT02379806.)