Comparative analysis of andexanet alfa and prothrombin complex concentrate in reversing anticoagulation by rivaroxaban ex vivo

Spontaneous hemorrhage arising from a proximal descending branch of the suprascapular artery

Suprascapular arterial hemorrhage is exceedingly uncommon. This case presents a 71-year-old male with a spontaneous suprascapular artery hemorrhage without a clear cause. He initially presented to the emergency department (ED) with an expanding soft tissue mass overlying his left neck, shoulder, and back. Computed tomography angiography (CTA) revealed active contrast extravasation from a branch of the left suprascapular artery, controlled by embolization. There are no prior case reports of spontaneous suprascapular artery hemorrhage, though rupture secondary to an inciting traumatic event has been described. This case highlights the importance of maintaining a high index of suspicion for vascular injury in patients with an enlarging soft tissue mass, as early diagnosis and intervention are crucial for achieving a favorable outcome.

Restoring hemostasis with prothrombin complex concentrate: benefits and risks in trauma-induced coagulopathy

PURPOSE OF THIS REVIEW

To provide evidence for the use of prothrombin complex concentrate (PCC) as a potential hemostatic treatment for trauma-induced coagulopathy with and without anticoagulants.

RECENT FINDINGS

PCC is effective in enhancing thrombin generation and achieving hemostasis in traumatized patients under anticoagulants. For vitamin K antagonist (VKA) reversal, it shows superior efficacy over fresh frozen plasma, achieving rapid normalization of the international normalized ratio normalization and reduced transfusion needs. In direct oral anticoagulant (DOAC)-associated bleeding, PCC offers an alternative when specific antidotes are unavailable. However, evidence from randomized trials in the field of trauma and coagulopathy is limited, and the results have shown conflicting outcomes in terms of mortality reduction. Further, following PCC application, thromboembolic risks remain a particular concern. Monitoring tools such as thrombin generation assays and point-of-care tests show promise but are not universally available.

SUMMARY

PCC is a valuable option for managing coagulopathy in specific settings, especially VKA and DOAC reversal. Based on current evidence, we caution against the use of PCC as a versatile hemostatic agent suitable for indications involving multiple clotting factor deficiencies for uncontrolled coagulopathic bleeding in trauma or other clinical settings outside anticoagulation reversal. The risk vs. benefit profile should be carefully examined, similar to any other agent.

Four-factor Prothrombin Complex Concentrate Use for Bleeding Management in Adult Trauma

The clinical use of four-factor prothrombin complex concentrate in adult trauma patients at risk of bleeding is supported by evidence for urgent reversal of oral anticoagulants but is controversial in acquired traumatic coagulopathy.

Urgent Reversal of Direct Oral Anticoagulants in Critical and Life-Threatening Bleeding: A Multidisciplinary Expert Consensus

Direct oral anticoagulants (DOACs) are increasingly being used due to their improved efficacy/safety ratio and lower clinical and economic burden when compared to vitamin K antagonists. However, bleeding is still the most frequent complication associated with DOACs, and although rare, bleeding episodes can be life-threatening or critical. The impact of DOAC anticoagulation activity during a bleeding event must be evaluated according to patient clinical assessment, dosage and time from last intake, the presence of comorbidities (especially kidney and liver dysfunction), and, whenever possible, coagulation tests. Unfortunately, DOACs' anticoagulation activity is not easily or usually detectable in routine common coagulation testing. Specific DOAC tests allow for specific drug monitoring, but they are too time consuming, and are usually unavailable in routine emergency practice. If a clinically relevant DOAC plasma concentration is assumed or proven in a severe bleeding scenario, DOAC reversal is needed to restore hemostasis. This experts' consensus provides a narrative review about DOAC reversal and practical life-threatening bleeding management in several scenarios (trauma, intracranial hemorrhage and gastrointestinal bleeding), focusing on the selection of patients to whom specific reversal agents should be given.

Andexanet alpha versus four-factor prothrombin complex concentrate in DOACs anticoagulation reversal: an updated systematic review and meta-analysis

BACKGROUND

There is currently a lack of evidence for the comparative effectiveness of Andexanet alpha and four-factor prothrombin complex concentrate (4F-PCC) in anticoagulation reversal of direct oral anticoagulants (DOACs). The primary aim of our systematic review was to verify which drug is more effective in reducing short-term all-cause mortality. The secondary aim was to determine which of the two reverting strategies is less affected by thromboembolic events.

METHODS

A systematic review and meta-analysis was performed.

RESULTS

Twenty-two studies were analysed in the systematic review and quantitative synthesis. In all-cause short-term mortality, Andexanet alpha showed a risk ratio (RR) of 0.71(95% CI 0.37-1.34) in RCTs and PSMs, compared to 4F-PCC (I2 = 81%). Considering the retrospective studies, the pooled RR resulted in 0.84 (95% CI 0.69-1.01) for the common effects model and 0.82 (95% CI 0.63-1.07) for the random effects model (I2 = 34.2%). Regarding the incidence of thromboembolic events, for RCTs and PSMs, the common and the random effects model exhibited a RR of 1.74 (95% CI 1.09-2.77), and 1.71 (95% CI 1.01-2.89), respectively, for Andexanet alpha compared to 4F-PCC (I2 = 0%). Considering the retrospective studies, the pooled RR resulted in 1.21 (95% CI 0.87-1.69) for the common effects model and 1.18 (95% CI 0.86-1.62) for the random effects model (I2 = 0%).

CONCLUSION

Considering a large group of both retrospective and controlled studies, Andexanet alpha did not show a statistically significant advantage over 4F-PCC in terms of mortality. In the analysis of the controlled studies alone, Andexanet alpha is associated with an increased risk of thromboembolic events.

CLINICAL TRIAL REGISTRATION

PROSPERO: International prospective register of systematic reviews, 2024, CRD42024548768.

Antidote vs. unspecific hemostatic agents for the management of direct oral anticoagulant-related bleeding in trauma

PURPOSE OF REVIEW

The advent of direct oral anticoagulants (DOACs) marks a significant milestone in anticoagulant treatment. However, DOACs can exacerbate bleeding, which is challenging for the treating clinician, especially when combined with traumatic injury.

RECENT FINDINGS

In major bleeding associated with DOACs, rapid reversal of the anticoagulant effects is crucial. Recent observational and nonrandomized interventional trials have demonstrated the effectiveness of the specific antidotes andexanet alfa and idarucizumab as well as the unspecific prothrombin complex concentrates (PCCs) to counteract the anticoagulant effects of DOACs. The European Society of Anaesthesiology and Intensive Care guideline for severe perioperative bleeding and the European trauma guideline propose divergent recommendations for the use of andexanet alfa and PCC to obtain hemostasis in Factor Xa inhibitor-related bleeding. The conflicting recommendations are due to limited evidence from clinical studies and the potential increased risk of thromboembolic complications after the administration of andexanet. Regarding dabigatran-associated major bleeding, both guidelines recommend the specific reversal agent idarucizumab as first-line therapy.

SUMMARY

Current guidelines recommend specific antidots and PCCs in DOAC-related major bleeding. Prospective randomized trials comparing specific vs. nonspecific hemostatic agents in the perioperative setting are needed to evaluate the effectiveness and safety of the hemostatic agents.

Andexanet alfa or prothrombin complex concentrate for acute reversal of oral factor Xa inhibitors: monitoring of antidote effects

This study in vitro comprehensively assessed reversal of the anticoagulant effects of rivaroxaban, an oral factor Xa inhibitor, using andexanet alfa and various prothrombin complex concentrate (PCC) products in a battery of tests. In static coagulation assays, andexanet alpha outperformed PCCs except for activated PCC being more effective in standard coagulation times. However, in a flow chamber model mimicking arterial shear, both andexanet alpha and high-concentration PCC restored fibrin formation, but not platelet adhesion. In the Russell's viper venom test and anti-Xa assay, only andexanet alpha could be tested for efficacy. The antidote effects of andexanet alpha and PCCs in restoring coagulation can be qualitatively or selectively demonstrated using in vitro coagulation tests.