At the Roche Diagnostics-sponsored satellite symposium ‘From Basic Research to Clinical Data: the Future of Patient Management’ hosted during the International Society for Haemostasis (ISTH) 2021 congress, Dr Jean M Connors MD gave an insightful presentation on thrombo-inflammation in the COVID-19 era.

The disease COVID-19 has been identified as a hypercoagulable state. The development of coagulopathy in patients with COVID-19 infection has been associated with disease severity and high incidence of thrombosis in such patients. Since the emergence of pandemic, several observational studies have obtained conflicting findings on the potential benefit of anticoagulation, which highlighted the urgent need for randomised controlled trials (RCTs).

Dr Connors presented findings from three recent RCTs including a combined analysis of three recent multiplatform RCTs (ATTACC, REMAP-CAP and ACTIV-4A) that aimed to assess the efficacy of standard prophylactic versus therapeutic doses of anticoagulant interventions for COVID-19. Following harmonisation of study criteria, combined data showed that, in comparison to standard prophylactic dose, therapeutic heparin dose may provide benefit in mortality and morbidity in moderately-ill hospitalised patients, regardless of D-dimer level. However, the ACTION trial found that therapeutic dose anticoagulation, primarily with rivaroxaban, plus an extended duration post-discharge conferred no clinical benefit in hospitalised patients over prophylactic anticoagulation. Additionally, increasing anticoagulation dose elicited no benefit in critically ill patients in either the multiplatform combined RCT analysis or the open-label RCT, INSPIRATION. More data related to antithrombotic strategies used in COVID-19 are set to emerge from a number of ongoing trials.

While the optimal anticoagulant intervention remains to be defined, a minimum of prophylactic anticoagulation is recommended for all hospitalised patients when not contraindicated. Findings from current RCTs could suggest anticoagulation alone may be insufficient to ameliorate COVID-19-associated thrombo-inflammation, therefore, a global effort is needed to identify effective thromboprophylactic strategies across the continuum of COVID-19 disease severity.