Vitamin K Antagonist Reversal for Urgent Surgery Using 4-Factor Prothrombin Complex Concentrates: A Randomized Clinical Trial.

Importance: Millions of people take vitamin K antagonists (VKAs). Some people who need urgent surgical procedures require rapid VKA reversal to prevent excessive intraoperative bleeding. Objective: To evaluate the hemostatic noninferiority of an investigational 4-factor prothrombin complex concentrate (4F-PCC) to a control 4F-PCC for rapid VKA reversal before urgent surgery. Design, Setting, and Participants: This phase 3, double-blind, noninferiority randomized clinical trial (LEX-209) was conducted in 24 hospitals in the US, Russia, Georgia, Belarus, Ukraine, and Romania from June 7, 2017, through November 8, 2021; the study was stopped in February 2022. Participants were adult patients taking VKA who had an international normalized ratio (INR) of 2 or higher and needed urgent surgery with a substantial bleeding risk (≥50 mL). Patients were randomized 1:1 to a single infusion of either the investigational 4F-PCC or the control 4F-PCC. Data analysis followed intention-to-treat and per-protocol approaches. Interventions: Single intravenous infusion was dosed by body weight and baseline INR. A dose of 25, 35, or 50 IU/kg of investigational 4F-PCC or control 4F-PCC was administered for baseline INR of 2 to less than 4, 4 to 6, or over 6, respectively. Main Outcome and Measure: The primary end point was hemostatic efficacy at surgery end. An independent adjudication board, blinded to the 4F-PCC treatment allocation, assessed hemostatic efficacy using an objective 4-point scale. Results: A total of 208 patients (median [range] age, 67.5 [31-92] years; 118 males [56.7%]) received the investigational (n = 105) or the control (n = 103) 4F-PCC. The median (range) dose was 25 (16-50) IU/kg in the investigational group and 25 (15-50) IU/kg in the control group, with a median (range) infusion time of 12 (8-50) minutes and 13 (7-30) minutes and a median (range) time from infusion to surgery start of 1.42 (0.25-15.25) hours and 1.50 (0.42-18.50) hours, respectively. Baseline median (range) INR was 3.05 (1.97-21.10) in the investigational group and 3.00 (2.00-11.30) in the control group. In the intention-to-treat analysis, the investigational 4F-PCC was noninferior to the control 4F-PCC, resulting in effective hemostasis in 94.3% of patients vs 94.2% of patients (proportion difference, 0.001; 95% CI, -0.080 to 0.082; P < .001), meeting the prespecified noninferiority margin of 0.15. An INR of 1.5 or lower at 30 minutes after infusion occurred in 78.1% of patients in the investigational group vs 71.8% of patients in the control group (proportion difference, 0.063; 95% CI, -0.056 to 0.181). Thrombotic events (2.9% vs 0%, respectively) and mortality (4.8% vs 1.0%, respectively) were no different than expected for 4F-PCC use. One patient in each treatment group discontinued due to adverse events (cardiac disorders unrelated to 4F-PCC). Conclusions and Relevance: This randomized clinical trial found that the investigational 4F-PCC was hemostatically noninferior to the control 4F-PCC for rapid VKA reversal in patients needing urgent surgery with considerable bleeding risk; the safety profile of these two 4F-PCCs was similar. These results support the investigational 4F-PCC as a therapeutic option for surgical patients requiring rapid VKA reversal. Trial Registration: ClinicalTrials.gov Identifier: NCT02740335.

Prothrombin complex concentrate for emergency surgery in patients on oral Xa-inhibitors.

BACKGROUND: It is uncertain whether prothrombin complex concentrate (PCC) improves hemostasis in patients on treatment with oral factor Xa-inhibitors (XaI) who require emergency surgery. OBJECTIVES: To evaluate whether, in patients with therapeutic levels of oral XaI, preoperative PCC prevents excessive bleeding during and after emergency surgery and is not associated with thrombotic complications. METHODS: We conducted a prospective cohort study wherein a fixed 2000 IU dose of 4-factor PCC was given to patients taking oral XaI with plasma XaI levels of at least 75 ng/mL before the emergency surgery with an expected blood loss of at least 50 mL. Patients were followed for 30 days. The primary efficacy outcome was the incidence of normal or mildly abnormal surgical hemostasis, as assessed by the surgeon; primary safety outcome was the incidence of thromboembolic events within 7 days. RESULTS: We included 20 patients, of which 50% were female, on apixaban (75%) or rivaroxaban (25%) with median XaI level of 128 ng/mL (range, 77-497 ng/mL). The median duration of surgery was 2 hours 42 minutes (range, 15 minutes to 8 hours 17 minutes). Normal or mildly abnormal hemostasis was observed in 16 patients (80%); 2 patients had moderately abnormal and 2 had severely abnormal hemostasis, 1 each of those was considered due to local or technical factors. There were 4 deaths (20%) secondary to underlying disease and 1 incidental pulmonary embolism in a patient with cancer. CONCLUSION: A fixed dose of PCC appears to control hemostasis in patients with therapeutic plasma levels of apixaban or rivaroxaban requiring emergency surgery.

Andexanet alfa versus PCC products for factor Xa inhibitor bleeding: A systematic review with meta-analysis.

Previous meta-analyses assessed andexanet alfa (AA) or prothrombin complex concentrate (PCC) products for the treatment of Factor Xa inhibitor (FXaI)-associated major bleeding. However, they did not include recent studies or assess the impact of the risk of bias. We conducted a systematic review with meta-analysis on the effectiveness of AA versus PCC products for FXaI-associated major bleeding, inclusive of the studies' risk of bias. PubMed and Embase were searched for comparative studies assessing major bleeding in patients using FXaI who received AA or PCC. We used the Methodological Index for NOn-Randomized Studies (MINORS) checklist and one question from the Joanna Briggs Institute (JBI) Critical Appraisal of Case Series tool to assess the risk of bias. Random-effects meta-analyses were performed to provide a pooled estimate for the effect of AA versus PCC products on hemostatic efficacy, in-hospital mortality, 30-day mortality, and thrombotic events. Low-moderate risk of bias studies were meta-analyzed separately, as well as combined with high risk of bias studies. Eighteen comparative evaluations of AA versus PCC were identified. Twenty-eight percent of the studies (n = 5) had low-moderate risk and 72% (n = 13) had a high risk of bias. Studies with low-moderate risk of bias suggested improvements in hemostatic efficacy [Odds Ratio (OR) 2.72 (95% Confidence Interval (CI): 1.15-6.44); one study], lower in-hospital mortality [OR 0.48 (95% CI: 0.38-0.61); three studies], and reduced 30-day mortality [OR 0.49 (95% CI: 0.30-0.80); two studies] when AA was used versus PCC products. When studies were included regardless of the risk of bias, pooled effects showed improvements in hemostatic efficacy [OR 1.36 (95% CI: 1.01-1.84); 12 studies] and reductions in 30-day mortality [OR 0.53 (95% CI: 0.37-0.76); six studies] for AA versus PCC. The difference in thrombotic events with AA versus PCC was not statistically significant in the low-moderate, high, or combined risk of bias groups. The evidence from low-moderate quality real-world studies suggests that AA is superior to PCC in enhancing hemostatic efficacy and reducing in-hospital and 30-day mortality. When studies are assessed regardless of the risk of bias, the pooled hemostatic efficacy and 30-day mortality risk remain significantly better with AA versus PCC.

Comparison of Fixed Versus Weight-Based Prothrombin Complex Concentrate Dosing Strategies for Factor Xa Inhibitor Reversal.

Background: Our institution introduced fixed-dose prothrombin complex concentrate (PCC) to streamline order verification and medication administration. Previous studies using fixed-dose PCC for vitamin K antagonist reversal showed comparable efficacy to weight-based dosing. Objective: To compare fixed versus weight-based PCC dosing for reversal of Factor Xa Inhibitor (FXaI) effects. Methods: Retrospective cohort study conducted at a tertiary care academic medical center. Patients who received PCC to reverse the effects of apixaban or rivaroxaban were eligible. Subjects in the fixed-dose group (5000 units or 2000 units) were compared to weight-based PCC (50 units/kg). The primary outcome was time between order entry and medication administration. Secondary outcomes included: average PCC dose, postadministration procedures, achieved hemostasis, 30-day mortality, hospital length of stay, and adverse drug events. Results: 72 patients received fixed-dose PCC and 101 received weight-based PCC. Median time between order entry and administration was 4.5 min shorter in the fixed-dose group compared to weight-based (34.5 vs 39 min, P = .10). In patients who received fixed-dose, 79.2% achieved hemostasis versus 71.3% in the weight-based group (RR = 1.11, 95% CI = 0.94-1.32). There was no difference in the number of subsequent hemorrhage-related surgeries (29.2% vs 36.7%, RR = 0.80, 95% CI = 0.51-1.24) or mortality rate (26.4% vs 35.6%, RR = 0.73, 95% CI = 0.46-1.17). There were zero adverse drug events reported. Rates of thrombosis were 2.8% and < 1% (P = .57) in the fixed and weight-based groups, respectively. Conclusion and Relevance: The fixed-dosing strategy did not reduce time to PCC administration nor impact hemostasis or mortality. These data support that the fixed-dosing method is a viable option.

Efficacy of human prothrombin complex concentrate in the treatment of warfarin overdose in patients receiving warfarin for mechanical heart valve replacement.

Warfarin, a widely utilized anticoagulant, is paramount for preventing thromboembolic events in patients with mechanical heart valve replacements. However, its narrow therapeutic index can lead to over-anticoagulation and overdose, resulting in serious health risks. This study examines the efficacy of human prothrombin complex concentrate (PCC) in managing warfarin overdose, in comparison with traditional treatments. A retrospective analysis was conducted on 162 adults who presented with warfarin overdose (INR > 5.0) at a tertiary care hospital between 2016 and 2020. Participants were divided into 2 groups-those treated with PCC (n = 57) and those treated with conventional methods (n = 105), including vitamin K and fresh frozen plasma. The primary outcome was the rate of reaching the target (International Normalized Ratio) INR within 24 hours. Secondary outcomes included transfusion requirements, thromboembolic events, adverse reactions, 30-day mortality, and length of hospital stay. PCC demonstrated significant efficacy, with 89.5% of patients achieving the target INR within 24 hours, compared to 64.8% in the control group (P < .05). The PCC group also had reduced transfusion requirements and a shorter average hospital stay. There was no significant difference in thromboembolic events or adverse reactions between the 2 groups, and the reduced 30-day mortality in the PCC group was not statistically significant. Human prothrombin complex concentrate is associated with rapid reaching the target INR, decreased transfusion needs, and shortened hospitalization, making it a promising option for warfarin overdose management. While the results are encouraging, larger, multicenter, randomized controlled trials are necessary to further validate these findings and optimize PCC administration protocols.

Four-factor prothrombin complex concentrate is not inferior to andexanet alfa for the reversal or oral factor Xa inhibitors: An Eastern Association for the Surgery of Trauma multicenter study.

BACKGROUND: Andexanet alfa (AA) is the only FDA-approved reversal agent for apixaban and rivaroxaban (DOAC). There are no studies comparing its efficacy with four-factor prothrombin complex concentrate (PCC). This study aimed to compare PCC to AA for DOAC reversal, hypothesizing noninferiority of PCC. METHODS: We performed a retrospective, noninferiority multicenter study of adult patients admitted from July 1, 2018, to December 31, 2019, who had taken a DOAC within 12 hours of injury, were transfused red blood cells (RBCs) or had traumatic brain injury, and received AA or PCC. Primary outcome was PRBC unit transfusion. Secondary outcome with intensive care unit length of stay. MICE imputation was used to account for missing data and zero-inflated Poisson regression was used to account for an excess of zero units of RBC transfused. Two units difference in RBC transfusion was selected as noninferior. RESULTS: Results: From 263 patients at 10 centers, 77 (29%) received PCC and 186 (71%) AA. Patients had similar transfusion rates across reversal treatment groups (23.7% AA vs. 19.5% PCC) with median transfusion in both groups of 0 RBC. According to the Poisson component, PCC increases the amount of RBC transfusion by 1.02 times (95% confidence interval, 0.79-1.33) compared with AA after adjusting for other covariates. The average amount of RBC transfusion (nonzero group) is 6.13. Multiplying this number by the estimated rate ratio, PCC is estimated to have an increase RBC transfusion by 0.123 (95% confidence interval, 0.53-2.02) units compared with AA. CONCLUSION: PCC appears noninferior to AA for reversal of DOACs for RBC transfusion in traumatically injured patients. Additional prospective, randomized trials are necessary to compare PCC and AA for the treatment of hemorrhage in injured patients on DOACs. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Evaluation of modified fixed dose four-factor prothrombin complex concentrate for warfarin reversal.

Non-activated four-factor prothrombin complex concentrate (4 F-PCC) has emerged as the preferred reversal strategy for patients on warfarin with life-threatening bleeding. Current dosing recommendations for 4 F-PCC require pre-treatment international normalized ratio (INR) and bodyweight values, resulting in ordering and administration delays. Studies have shown that alternative dosing regimens are safe and efficacious. This retrospective, single-center, pre- and post-protocol analysis was conducted to assess the efficacy of a pharmacist driven modified fixed-dose 4 F-PCC regimen versus package insert weight- and INR-based dosing regimen for warfarin reversal. The primary outcome was achievement of INR less than two. Secondary outcomes included dose and cost of 4 F-PCC, a time analysis, incidence of concomitant vitamin K administration, and incidence of thrombosis within seven days of 4 F-PCC. There were 195 patients included in the analysis, with 74 in the pre-cohort and 121 in the post-cohort. Baseline characteristics were similar between cohorts with the most common indication for warfarin use being atrial fibrillation (48.6% versus 47.1%) and reversal being intracerebral hemorrhage (68.9% versus 43.0%). Achievement of the primary endpoint occurred in 92% versus 95% (p = 0.097) of patients. A statistically significant difference was seen between cohorts regarding median dose and cost of 4 F-PCC administered (p < 0.001). Eleven thromboembolic events occurred with three events in the pre-cohort and eight events in the post-cohort (p = 0.453). A fixed-dose of 1500IU of 4 F-PCC was effective in reversing INR to less than two in most patients regardless of reversal indication with minimal thrombotic risks.

Effect of low- versus high-dose 4-factor prothrombin complex concentrate in factor Xa inhibitor-associated bleeding: A qualitative systematic review.

PURPOSE: The purpose of this review is to evaluate current literature on the treatment of factor Xa inhibitor-associated bleeds with 4-factor prothrombin complex concentrate (4F-PCC), with a focus on the effect of low versus high dosing of 4F-PCC on hemostatic efficacy and safety outcomes. SUMMARY: A search of PubMed and EBSCOhost was performed to identify studies evaluating patients with a factor Xa inhibitor-bleed treated with 4F-PCC at either low or high doses. Studies of patients receiving alternative reversal agents such as fresh frozen plasma and andexanet alfa or where no comparator group was evaluated were excluded from the analysis. To assess the effect of these 4F-PCC dosing strategies, the primary outcome of interest was hemostatic efficacy. Four studies meeting inclusion criteria were included in this review. In each of the included studies, similar rates of hemostatic efficacy, hospital mortality, and venous thromboembolism were observed in the low- and high-dose cohorts. CONCLUSION: These results suggest low- and high-dose 4F-PCC may confer similar clinical effectiveness and safety; however, these findings should be evaluated and confirmed with future prospective studies.

Fitusiran prophylaxis in people with hemophilia A or B who switched from prior BPA/CFC prophylaxis: the ATLAS-PPX trial.

ABSTRACT: Fitusiran, a subcutaneous investigational small interfering RNA therapeutic, targets antithrombin to rebalance hemostasis in people with hemophilia A or B (PwHA/B), irrespective of inhibitor status. This phase 3, open-label study evaluated the efficacy and safety of fitusiran prophylaxis in males aged ≥12 years with hemophilia A or B, with or without inhibitors, who received prior bypassing agent (BPA)/clotting factor concentrate (CFC) prophylaxis. Participants continued their prior BPA/CFC prophylaxis for 6 months before switching to once-monthly 80 mg fitusiran prophylaxis for 7 months (onset and efficacy periods). Primary end point was annualized bleeding rate (ABR) in the BPA/CFC prophylaxis and fitusiran efficacy period. Secondary end points included spontaneous ABR (AsBR) and joint ABR (AjBR). Safety and tolerability were assessed. Of 80 enrolled participants, 65 (inhibitor, n = 19; noninhibitor, n = 46) were eligible for ABR analyses. Observed median ABRs were 6.5 (interquartile range [IQR], 2.2-19.6)/4.4 (IQR, 2.2-8.7) with BPA/CFC prophylaxis vs 0.0 (IQR, 0.0-0.0)/0.0 (IQR, 0.0-2.7) in the corresponding fitusiran efficacy period. Estimated mean ABRs were substantially reduced with fitusiran by 79.7% (P = .0021) and 46.4% (P = .0598) vs BPA/CFC prophylaxis, respectively. Forty-one participants (63.1%) experienced 0 treated bleeds with fitusiran vs 11 (16.9%) with BPAs/CFCs. Median AsBR and AjBR were both 2.2 with BPA/CFC prophylaxis and 0.0 in the fitusiran efficacy period. Two participants (3.0%) experienced suspected or confirmed thromboembolic events with fitusiran. Once-monthly fitusiran prophylaxis significantly reduced bleeding events vs BPA/CFC prophylaxis in PwHA/B, with or without inhibitors, and reported adverse events were generally consistent with previously identified risks of fitusiran. This trial was registered at www.ClinicalTrials.gov as #NCT03549871.

Assessment of Temporary Warfarin Reversal in Patients With Left Ventricular Assist Devices: the KVAD Study.

BACKGROUND: Patients with left ventricular assist devices (LVADs) require interruption of warfarin for invasive procedures, but parenteral bridging is associated with many complications. Four-factor prothrombin complex concentrate (4F-PCC) can temporarily restore hemostasis in patients undergoing anticoagulation with warfarin. OBJECTIVES: This pilot study evaluated the strategy of using variable-dose 4F-PCC to immediately and temporarily reverse warfarin before invasive procedures without holding warfarin in patients with LVADs. The duration of effect of 4F-PCC on factor levels and time to reestablish therapeutic anticoagulation post procedure were assessed. METHODS: Adult patients with LVADs and planned invasive procedures were enrolled from a single center. Warfarin was continued uninterrupted. The 4F-PCC dose administered immediately pre-procedure was based on study protocol. International normalized ratio (INR)- and vitamin K-dependent factor levels were collected before and during the 48 hours after 4F-PCC administration. The use of parenteral bridging, International Society for Thrombosis and Haemostasis major and clinically relevant nonmajor bleeding (CRNMB) and thromboembolic events at 7 and 30 days were collected. RESULTS: In 21 episodes of 4F-PCC reversal, median baseline INR was 2.7 (IQR 2.2-3.2). The median dosage of 4F-PCC administered was 1794 units (IQR 1536-2130). At 24 and 48 hours post 4F-PCC administration, median INRs were 1.8 (IQR 1.7-2.0) and 2.0 (IQR 1.9-2.4). Two patients required postoperative bridging. One patient experienced major bleeding within 72 hours, and 2 experienced CRNMB within 30 days. There were no thromboembolic events. Baseline and post 4F-PCC vitamin K-dependent factor levels corresponded with changes in INR values. The median time to achieve therapeutic INR post-procedure was 2.5 days (IQR, 1-4). CONCLUSION: Administration of 4F-PCC for temporary reversal of warfarin for invasive procedures in patients with LVADs allowed for continued warfarin dosing with minimal use of post-intervention bridging, limited bleeding and no thromboembolic events.

Comparison of Low Dose Recombinant Factor VIIa and 4-Factor Prothrombin Complex Concentrate for Treatment of Bleeding Related to Cardiac Surgery.

Background: Recombinant factor VIIa (rFVIIa) and prothrombin concentrate complex (PCC) are used for uncontrolled bleeding in cardiac surgery (CS), however, there are limited direct comparisons of these agents. Objective: To evaluate the efficacy and safety of rFVIIa and PCC in CS related bleeding. Methods: This retrospective study included adult CS patients who received either low dose rFVIIa (<30 mcg/kg) or 4-factor PCC. The primary outcome was transfusion requirements of packed red blood cells (pRBC) within 6 hours of factor administration. Secondary efficacy outcomes included transfusion requirements 0-18 hours, doses of additional factor product, thrombotic events, and acute kidney injury (AKI). Results: A total of 179 patients were included (n = 78 rFVIIa; n = 101 PCC). Of patients who received blood products, there was no difference in the requirement of pRBCs within 6 hours (73.8 vs 68.9%, P = .5359) or in the median amount of pRBC transfused (500 mL vs 640 mL, P = .0723) in the rFVIIa and PCC groups respectively. Patients in the PCC group were more likely to require additional factor products (24.4% vs 47.5%, P = .0015), develop AKI (12.8% vs 25.7%, P = .0325), have longer ICU lengths of stay [2 (IQR 1-5) vs 4 (IQR 2-6), P = .0487] and greater in-hospital mortality (2.6% vs 10.9%, P = .033). There was no difference in thrombotic events. Conclusion: Although, there was no difference in pRBC transfusion requirements between PCC and rFVIIa, more patients in the PCC group required additional factor products and had increased adverse effects. Further comparisons of PCC and rFVIIa are warranted.

Hemostatic Efficacy and Safety of Weight-Based Versus Fixed-Dose 4F-PCC for Vitamin K Antagonist Reversal.

Background: Four-factor prothrombin complex concentrate (4F-PCC) is indicated for vitamin K antagonist (VKA) reversal but is associated with thrombotic events (TE). In 2018, the institution revised 4F-PCC dosing for VKA reversal from INR and weight-based dosing to a fixed-dose of 1500 units. Objective: The purpose of this study was to compare hemostatic efficacy and TE rate of fixed-dose 4PCC to weight-based dosing. Methods: This was a retrospective, single-center, quasi-experimental study of adult patients who received 4F-PCC for VKA reversal from January 2014 through May 2016 (INR and weight-based dosing) or April through October 2018 (fixed-dosing). The primary endpoint was hemostatic efficacy, defined by achieving an INR of ≤1.4, or an INR of ≤1.7 with evidence of hemostasis. The key secondary endpoint was TE within 14 days of 4F-PCC administration. Data were analyzed using descriptive statistics, chi-squared for nominal data and Mann-Whitney U for ordinal and continuous data. Results: The study included 163 patients who received weight-based dosing and 45 who received fixed-dose 4F-PCC. Hemostatic efficacy was 76.9% of patients in the weight-based group and 77.4% of patients in the fixed-dose group (P = .229). TE occurred in 13.5% of the weight-based vs 6.7% of the fixed-dose group (P = .181). Conclusion: This study found no difference in hemostatic efficacy with fixed-dose 4F-PCC for VKA reversal compared to INR and weight-based dosing. The occurrence of TE was reduced by 50% with the 4F-PCC fixed-dose strategy; however, this difference was not statistically significant. Further randomized studies are needed to confirm these results.

Efficacy and Safety of Early Administration of 4-Factor Prothrombin Complex Concentrate in Patients With Trauma at Risk of Massive Transfusion: The PROCOAG Randomized Clinical Trial.

Importance: Optimal transfusion strategies in traumatic hemorrhage are unknown. Reports suggest a beneficial effect of 4-factor prothrombin complex concentrate (4F-PCC) on blood product consumption. Objective: To investigate the efficacy and safety of 4F-PCC administration in patients at risk of massive transfusion. Design, Setting, and Participants: Double-blind, randomized, placebo-controlled superiority trial in 12 French designated level I trauma centers from December 29, 2017, to August 31, 2021, involving consecutive patients with trauma at risk of massive transfusion. Follow-up was completed on August 31, 2021. Interventions: Intravenous administration of 1 mL/kg of 4F-PCC (25 IU of factor IX/kg) vs 1 mL/kg of saline solution (placebo). Patients, investigators, and data analysts were blinded to treatment assignment. All patients received early ratio-based transfusion (packed red blood cells:fresh frozen plasma ratio of 1:1 to 2:1) and were treated according to European traumatic hemorrhage guidelines. Main Outcomes and Measures: The primary outcome was 24-hour all blood product consumption (efficacy); arterial or venous thromboembolic events were a secondary outcome (safety). Results: Of 4313 patients with the highest trauma level activation, 350 were eligible for emergency inclusion, 327 were randomized, and 324 were analyzed (164 in the 4F-PCC group and 160 in the placebo group). The median (IQR) age of participants was 39 (27-56) years, Injury Severity Score was 36 (26-50 [major trauma]), and admission blood lactate level was 4.6 (2.8-7.4) mmol/L; prehospital arterial systolic blood pressure was less than 90 mm Hg in 179 of 324 patients (59%), 233 patients (73%) were men, and 226 (69%) required expedient hemorrhage control. There was no statistically or clinically significant between-group difference in median (IQR) total 24-hour blood product consumption (12 [5-19] U in the 4F-PCC group vs 11 [6-19] U in the placebo group; absolute difference, 0.2 U [95% CI, -2.99 to 3.33]; P = .72). In the 4F-PCC group, 56 patients (35%) presented with at least 1 thromboembolic event vs 37 patients (24%) in the placebo group (absolute difference, 11% [95% CI, 1%-21%]; relative risk, 1.48 [95% CI, 1.04-2.10]; P = .03). Conclusions and Relevance: Among patients with trauma at risk of massive transfusion, there was no significant reduction of 24-hour blood product consumption after administration of 4F-PCC, but thromboembolic events were more common. These findings do not support systematic use of 4F-PCC in patients at risk of massive transfusion. Trial Registration: ClinicalTrials.gov Identifier: NCT03218722.

Avaliação do perfil clínico-terapêutico e da resposta à profilaxia dos portadores de hemofilia A e B em um centro de referência no Ceará / Evaluation of the clinical-therapeutic profile and the response to prophylaxis of patients with hemophilia A and B in a reference center in Ceará

Objetivo: Avaliar o perfil clínico-terapêutico e a resposta à profilaxia em pacientes hemofílicos A e B em um centro de referência no Ceará. Métodos: Estudo de coorte retrospectivo, com dados de 133 hemofílicos A e B, em profilaxia entre 2016 e 2021, por meio de prontuários médicos e sistema Web Coagulopatias. Resultados: Os pacientes todos do sexo masculino em sua maioria foram hemofílicos A (93,2%), na forma grave, residentes em Fortaleza, com maior prevalência do município de Guaiúba. A maioria fazia uso de Fator VIII recombinante e em profilaxia secundária, em relação ao comprometimento articular a maioria não apresentou relato de hemartroses (66,9%), articulação-alvo (87,9%) ou artropatia (54,9%), porém os hemofílicos em profilaxia terciária apresentaram um maior comprometimento articular em relação a profilaxia primária e secundária. Verificou-se uma correlação negativa entre o tempo de profilaxia e a dose de fator utilizada, demonstrando que quanto maior o tempo de profilaxia menor a dose do fator utilizada. Um total de 13 hemofílicos A grave desenvolveram inibidor de fator VIII realizando imunotolerância (ITI) com sucesso total em 84,6%. Por meio da curva ROC, foi verificado uma associação entre a necessidade de ITI e a dose de fator de coagulação, com acurácia de 67,7% de que o uso de doses maiores de fator predispõe ao desenvolvimento de inibidores. Conclusão: Os dados do estudo permitem inferir que quanto mais precoce o tratamento de profilaxia menor é comprometimento articular, dose do fator utilizada e menor predisposição de desenvolver inibidores dos fatores da coagulação.

Objective: to evaluate the clinical-therapeutic profile and response to prophylaxis in hemophiliac A and B patients at a referral center in Ceará. Methods: Retrospective cohort study, with data from 133 hemophiliacs A and B, undergoing prophylaxis between 2016 and 2021, using medical records and the Web Coagulopathies system. Results: Most of the patients were male patients with severe hemophilia A (93.2%), residing in Fortaleza, with a higher prevalence in the city of Guaiúba. Most made use of recombinant Factor VIII and in secondary prophylaxis, in relation to joint involvement, the majority did not report hemarthroses (66.9%), target joint (87.9%) or arthropathy (54.9%). however, hemophiliacs on tertiary prophylaxis showed greater joint impairment in relation to primary and secondary prophylaxis. There was a negative correlation between the prophylaxis time and the factor dose used, demonstrating that the longer the prophylaxis time, the lower the factor dose used. A total of 13 severe A hemophiliacs developed factor VIII inhibitor performing immunotolerance (ITI) with total success in 84.6%. Using the ROC curve, an association was verified between the need for ITI and the dose of coagulation factor, with an accuracy of 67.7% that the use of higher doses of factor predisposes to the development of inhibitors. Conclusion: The study data allow us to infer that the earlier the prophylaxis treatment, the less joint impairment, the dose of the factor used and the less predisposition to develop coagulation factor inhibitors.

Indirect antiplatelet effects of rivaroxaban in a patient with intracranial hemorrhage: An underappreciated coagulopathy of factor Xa inhibitors?

Rivaroxaban is a direct oral anticoagulant (DOAC) used for prophylaxis and treatment of many prothrombotic states. The anticoagulation effects of rivaroxaban are produced by selectively binding and inhibiting factor Xa, causing delayed thrombin generation. Additionally, the delay in thrombin generation produces an indirect, dose dependent antiplatelet effect via reduction in tissue factor platelet aggregation. As with any anticoagulant, rivaroxaban use increases a patient's risk for major and minor hemorrhagic events. With mortality rates reported as high as 25% for those who experience an intracranial hemorrhage (ICH), immediate mitigation of hematoma and hemorrhage volume expansion is imperative. Management strategies include utilizing prothrombin complex concentrates (PCC) and factor Xa inhibitor specific antidotes, such as coagulation factor Xa recombinant, inactivated-zhzo. Routine monitoring or management of DOAC induced antiplatelet effects is ill-defined and not a part of routine standard of care. We report the first case, to our knowledge, of rivaroxaban's indirect antiplatelet effects identified by platelet function assays and managed with four-factor PCC and desmopressin in a patient experiencing an ICH. Further exploration is needed to determine the true clinical impact attributed to rivaroxaban's antiplatelet effects.

In silico evaluation of limited sampling strategies for individualized dosing of extended half-life factor IX concentrates in hemophilia B patients.

PURPOSE: Hemophilia B is a bleeding disorder, caused by a factor IX (FIX) deficiency. Recently, FIX concentrates with extended half-life (EHL) have become available. Prophylactic dosing of EHL-FIX concentrates can be optimized by assessment of individual pharmacokinetic (PK) parameters. To determine these parameters, limited sampling strategies (LSSs) may be applied. The study aims to establish adequate LSSs for estimating individual PK parameters of EHL-FIX concentrates using in silico evaluation. METHODS: Monte Carlo simulations were performed to obtain FIX activity versus time profiles using published population PK models for N9-GP (Refixia), rFIXFc (Alprolix), and rIX-FP (Idelvion). Fourteen LSSs, containing three or four samples taken within 8 days after administration, were formulated. Bayesian analysis was applied to obtain estimates for clearance (CL), half-life (t1/2), time to 1% (Time1%), and calculated weekly dose (Dose1%). Bias and precision of these estimates were assessed to determine which LSS was adequate. RESULTS: For all PK parameters of N9-GP, rFIXFc and rIX-FP bias was generally acceptable (range: -5% to 5%). For N9-GP, precision of all parameters for all LSSs was acceptable (< 25%). For rFIXFc, precision was acceptable for CL and Time1%, except for t1/2 (range: 27.1% to 44.7%) and Dose1% (range: 12% to 29.4%). For rIX-FP, all LSSs showed acceptable bias and precision, except for Dose1% using LSS with the last sample taken on day 3 (LSS 6 and 10). CONCLUSION: Best performing LSSs were LSS with samples taken at days 1, 5, 7, and 8 (N9-GP and rFIXFc) and at days 1, 4, 6, and 8 (rIX-FP), respectively.

Fixed Versus Variable Dosing of Prothrombin Complex Concentrate for Bleeding Complications of Vitamin K Antagonists-The PROPER3 Randomized Clinical Trial.

STUDY OBJECTIVE: To determine if a fixed dose of 1000 IU of 4-factor prothrombin complex concentrate (4F-PCC) is as effective as traditional variable dosing based on body weight and international normalized ratio (INR) for reversal of vitamin K antagonist (VKA) anticoagulation. METHODS: In this open-label, multicenter, randomized clinical trial, patients with nonintracranial bleeds requiring VKA reversal with 4F-PCC were allocated to either a 1,000-IU fixed dose of 4F-PCC or the variable dose. The primary outcome was the proportion of patients with effective hemostasis according to the International Society of Thrombosis and Haemostasis definition. The design was noninferiority with a lower 95% confidence interval of no more than -6%. When estimating sample size, we assumed that fixed dosing would be 4% superior. RESULTS: From October 2015 until January 2020, 199 of 310 intended patients were included before study termination due to decreasing enrollment rates. Of the 199 patients, 159 were allowed in the per-protocol analysis. Effective hemostasis was achieved in 87.3% (n=69 of 79) in fixed compared to 89.9% (n=71 of 79) in the variable dosing cohort (risk difference 2.5%, 95% confidence interval -13.3 to 7.9%, P=.27). Median door-to-needle times were 109 minutes (range 16 to 796) in fixed and 142 (17 to 1076) for the variable dose (P=.027). INR less than 2.0 at 60 minutes after 4F-PCC infusion was reached in 91.2% versus 91.7% (P=1.0). CONCLUSION: The large majority of patients had good clinical outcome after 4F-PCC use; however, noninferiority of the fixed dose could not be demonstrated because the design assumed the fixed dose would be 4% superior. Door-to-needle time was shortened with the fixed dose, and INR reduction was similar in both dosing regimens.

Fixed-dose prothrombin complex concentrate for emergent warfarin reversal among patients with intracranial hemorrhage.

INTRODUCTION: Four-factor prothrombin complex concentrate (4PCC) is the preferred reversal agent for warfarin reversal, although the ideal dose is unknown. Fixed-dose 4PCC offers simplified dosing compared to standard-dosing algorithms with potentially lower risks of thromboembolic complications given lower doses are typically utilized. METHODS: Retrospective, observational, multicentered, pre- post- study of patients who received 4PCC for warfarin reversal among four hospitals within the same regional health system. Standard-dose patients received variable doses ranging from 25 to 50 units/kg based on total body weight and initial INR and fixed-dose patients received 2000 units. The primary outcome was achievement of a target INR ≤ 1.4 on the first post-4PCC INR result. RESULTS: After exclusions, 48 and 42 patients were analyzed in the standard-dose and fixed-dose groups, respectively. There was no difference in the ability to achieve a target INR of ≤1.4 (82.6% vs 81.5%, p = 0.14). Both groups received the same median dose of 2000 units, although fixed-dose patients actually received a higher weight-based dose than standard-dose patients (27 units/kg vs 24.5 units/kg). CONCLUSION: A fixed-dose 4PCC regimen of 2000 units among patients with ICH was as effective as standard-dose 4PCC for INR reversal among patients with ICH. However, fixed-doses of 2000 units at times exceeded standard 4PCC doses which may be contradictory to the goals of fixed-dose 4PCC for warfarin reversal.

Safety and efficacy of a strategy of vitamin K antagonist reversal with prothrombin complex concentrates compared to vitamin K in patients with hip fracture.

Background: Increased preoperative delay in patients with hip fractures may be responsible for increased morbidity and mortality. We hypothesized that a strategy of reversal of vitamin K antagonist (VKA) by prothrombin complexes concentrates (PCCs), as compared to vitamin K, is safe and reduces preoperative delay and hospital length of stay (LOS). Methods: In this pilot study, we reviewed the records of patients admitted to a university-affiliated hospital for hip fracture between Jan. 1, 2012, and Dec. 31, 2016, who were taking VKA. Patients were stratified according to reversal strategy (vitamin K v. PCC). Adverse effects, time to surgery, LOS and mortality were collected from the electronic medical record and were compared between the 2 study groups and a control group not treated with VKA. Results: A total of 141 patients were included in the study: 65 in the vitamin K group, 26 in the PCC group and 50 in the control group. The median preoperative delay in the PCC group (20 h [interquartile range (IQR)] 13-25 h]) and the control group (20 h [IQR 15-33 h]) was lower than that in the vitamin K group (45 h [IQR 31-52 h]) (p < 0.001). Patients in the PCC group had a shorter median hospital LOS than those in the vitamin K group (6 d [IQR 4-9 d] v. 8 d [IQR 6-11 d], p < 0.05). No difference was observed in the proportion of patients who received a red blood cell transfusion, or had thrombotic or hemorrhagic complications. No difference in mortality at 12 months was observed between the groups. Conclusion: In patients with hip fracture, the use of PCCs as compared to vitamin K to reverse the effect of VKA significantly reduced preoperative delay and hospital LOS, and was not associated with an increase in the rates of thrombotic or hemorrhagic complications. Prospective studies involving a greater number of patients are required to confirm these promising results.

Contexte: L'allongement du délai préopératoire chez les patients atteints d'une fracture de la hanche pourrait expliquer l'augmentation de la morbidité et de la mortalité. Selon notre hypothèse, une stratégie d'inversion des antagonistes de la vitamine K (AVK) au moyen de concentrés de complexes prothrombiques (CCP), plutôt que de vitamine K, est sécuritaire et réduit le délai préopératoire et la durée du séjour hospitalier. Méthodes: Pendant cette étude pilote, nous avons passé en revue les dossiers de patients sous AVK admis dans un centre universitaire pour fracture de la hanche entre le 1er janvier 2012 et le 31 décembre 2016. Les patients ont été stratifiés selon la stratégie d'inversion choisie (vitamine K c. CCP). Les effets indésirables, le délai préopératoire, la durée du séjour hospitalier et la mortalité ont été recueillis à partir des dossiers médicaux électroniques et ont été comparés entre les 2 groupes de l'étude et un groupe témoin non sous AVK. Résultats: En tout, 141 patients ont été inclus dans l'étude, 65 dans le groupe sous vitamine K, 26 dans le groupe sous CCP et 50 dans le groupe témoin. Le délai préopératoire médian pour le groupe sous CCP (20 h [éventail interquartile (ÉIQ)] 13­25 h]) et le groupe témoin (20 h [ÉIQ 15­33 h]) a été plus bref que pour le groupe sous vitamine K (45 h [ÉIQ 31­52 h]) (p < 0,001). Les patients du groupe sous CCP ont eu un séjour hospitalier médian plus bref que les patients du groupe sous vitamine K (6 j [ÉIQ 4­9 j] c. 8 j [ÉIQ 6­11 j]) (p < 0,05). Aucune différence n'a été observée quant à la proportion de patients ayant reçu une transfusion de culot globulaire ou ayant manifesté des complications thrombotiques ou hémorragiques. Aucune différence quant à la mortalité à 12 mois n'a été observée entre les groupes. Conclusion: Chez les patients atteints d'une fracture de la hanche, l'utilisation des CCP plutôt que de la vitamine K pour inverser l'effet des AVK a significativement abrégé le délai préopératoire et la durée du séjour hospitalier, et n'a pas été associée à une augmentation des taux de complications thrombotiques ou hémorragiques. Des études prospectives sur un plus grand nombre de patients sont nécessaires pour confirmer ces résultats prometteurs.