Recombinant factor VIIa: safety and efficacy:

Tranexamic acid versus placebo in individuals with intracerebral haemorrhage treated within 2 h of symptom onset (STOP-MSU): an international, double-blind, randomised, phase 2 trial

BACKGROUND

Tranexamic acid, an antifibrinolytic agent, might attenuate haematoma growth after an intracerebral haemorrhage. We aimed to determine whether treatment with intravenous tranexamic acid within 2 h of an intracerebral haemorrhage would reduce haematoma growth compared with placebo.

METHODS

STOP-MSU was an investigator-led, double-blind, randomised, phase 2 trial conducted at 24 hospitals and one mobile stroke unit in Australia, Finland, New Zealand, Taiwan, and Viet Nam. Eligible participants had acute spontaneous intracerebral haemorrhage confirmed on non-contrast CT, were aged 18 years or older, and could be treated with the investigational product within 2 h of stroke onset. Using randomly permuted blocks (block size of 4) and a concealed pre-randomised assignment procedure, participants were randomly assigned (1:1) to receive intravenous tranexamic acid (1 g over 10 min followed by 1 g over 8 h) or placebo (saline; matched dosing regimen) commencing within 2 h of symptom onset. Participants, investigators, and treating teams were masked to group assignment. The primary outcome was haematoma growth, defined as either at least 33% relative growth or at least 6 mL absolute growth on CT at 24 h (target range 18-30 h) from the baseline CT. The analysis was conducted within the estimand framework with primary analyses adhering to the intention-to-treat principle. The primary endpoint and secondary safety endpoints (mortality at days 7 and 90 and major thromboembolic events at day 90) were assessed in all participants randomly assigned to treatment groups who did not withdraw consent to use any data. This study was registered with ClinicalTrials.gov, NCT03385928, and the trial is now complete.

FINDINGS

Between March 19, 2018, and Feb 27, 2023, 202 participants were recruited, of whom one withdrew consent for any data use. The remaining 201 participants were randomly assigned to either placebo (n=98) or tranexamic acid (n=103; intention-to-treat population). Median age was 66 years (IQR 55-77), and 82 (41%) were female and 119 (59%) were male; no data on race or ethnicity were collected. CT scans at baseline or follow-up were missing or of inadequate quality in three participants (one in the placebo group and two in the tranexamic acid group), and were considered missing at random. Haematoma growth occurred in 37 (38%) of 97 assessable participants in the placebo group and 43 (43%) of 101 assessable participants in the tranexamic acid group (adjusted odds ratio [aOR] 1·31 [95% CI 0·72 to 2·40], p=0·37). Major thromboembolic events occurred in one (1%) of 98 participants in the placebo group and three (3%) of 103 in the tranexamic acid group (risk difference 0·02 [95% CI -0·02 to 0·06]). By 7 days, eight (8%) participants in the placebo group and eight (8%) in the tranexamic acid group had died (aOR 1·08 [95% CI 0·35 to 3·35]) and by 90 days, 15 (15%) participants in the placebo group and 19 (18%) in the tranexamic acid group had died (aOR 1·61 [95% CI 0·65 to 3·98]).

INTERPRETATION

Intravenous tranexamic acid did not reduce haematoma growth when administered within 2 h of intracerebral haemorrhage symptom onset. There were no observed effects on other imaging endpoints, functional outcome, or safety. Based on our results, tranexamic acid should not be used routinely in primary intracerebral haemorrhage, although results of ongoing phase 3 trials will add further context to these findings.

FUNDING

Australian Government Medical Research Future Fund.

Spontaneous hemorrhage after external ventricular drain placement in the setting of low factor VII secondary to liver cirrhosis

BACKGROUND

Alterations in normal coagulation and hemostasis are critical issues that require special attention in the neurosurgical patient. These disorders pose unique challenges in the management of these patients who often have concurrent acute ischemic and hemorrhagic injuries. Although neurosurgical intervention in such cases may be unavoidable and potentially life-saving, these patients should be closely observed after instrumentation.

CASE DESCRIPTION

A 57-year-old male with liver cirrhosis secondary to amyloid light-chain amyloidosis was admitted to the intensive care unit for the management of delayed hydrocephalus. An external ventricular drain (EVD) was placed for the treatment and monitoring of hydrocephalus. Five days after EVD placement, a head computed tomography scan revealed a tract hemorrhage. However, on repeated imaging, the size of the hemorrhage continued to increase despite aggressive blood pressure control and several doses of phytonadione. Extensive coagulopathy workup was remarkable for low factor VII levels. In that setting, recombinant activated factor VII was administered to normalize factor VII levels, and the tract hemorrhage stabilized.

CONCLUSION

To the best of our knowledge, this is the first case of spontaneous hemorrhage after EVD placement in the setting of liver cirrhosis-associated factor VII deficiency. Our case highlights the importance of identifying coagulation disorders in neurosurgical patients at high risk for coagulopathy and closely monitoring them postoperatively.

Successful Desensitization Protocol in an Infant Following Anaphylaxis Secondary to Recombinant Factor VIIa

Background: Recombinant factor VIIa (rFVIIa) is a highly purified recombinant protein. It is approved for the treatment and prevention of bleeding episodes associated with congenital factor VII deficiency, congenital hemophilia with inhibitors, and Glanzmann's thrombasthenia. The most commonly reported adverse events are thrombolytic in nature. In this report, we present a successful desensitization protocol administered to an infant with a history of anaphylaxis to rFVIIa. Case: A male infant with a history of gingival bleeding at the age of 6 months was diagnosed with factor VII deficiency with a factor VII level of 1%. His sister also had diagnosis of factor VII deficiency. Our patient was hospitalized at 10 months of age with generalized petechiae and bloody stools. Twenty minutes after administration of rFVIIa, he developed anaphylaxis that responded to epinephrine and supportive care. Subsequently he was evaluated at the allergy clinic, where a skin prick test with rFVIIa was negative. However, the intradermal skin test, applied with 1/1,000 (1 μg/1 mL, 0.1 mL) dilution of rFVIIa, showed induration of 8 mm (positive reaction). Because there is no alternative treatment for factor VII deficiency, we developed a successful 13-step desensitization protocol with rFVIIa (NovoSeven^®). Desensitization was performed an additional 2 times using the same protocol, one of which was for a head injury and the other for a swollen knee since the period between the doses was ∼3 months. Conclusion: Allergic reactions, such as anaphylaxis can occur without prior exposure. This can be due to the high molecular weight and structural property of the biological agent. In this report, we present an effective desensitization protocol for an infant with a history of anaphylaxis to rFVIIa. Desensitization protocols in this age group should be carried out in a medical facility and with specialized staff and equipment prepared to care for anaphylaxis.

Recombinant Factor VIIa to Manage Major Bleeding from Newer Parenteral Anticoagulants

Objective

To evaluate the use of recombinant factor VIIa (rFVIIa) to reverse major bleeding from newer parenteral anticoagulant therapy.

Data sources

MEDLINE/PubMed was searched from January 2000 through December 2009 using the terms recombinant factor VIIa, rFVIIa, NovoSeven, enoxaparin, argatroban, fondaparinux, lepirudin, bivalirudin, idraparinux, nadroparin, hirudin, and desirudin. References of identified articles were reviewed.

Data synthesis

Data evaluating the role of rFVIIa to reverse major bleeding from newer parenteral anticoagulant therapy is limited to case reports and small laboratory investigations. Laboratory investigations suggest that rFVIIa may be effective in reversing the hemostatic effects of newer parenteral anticoagulants. In most case reports analyzed, standard interventions for bleeding (eg, fresh frozen plasma, packed red blood cells) were attempted prior to using rFVIIa. Sixteen published cases describe the use of rFVIIa to reverse major bleeding from low-molecular-weight heparins, synthetic pentasaccharides, and direct thrombin inhibitors. Initial doses ranged from 20 to 120 μg/kg. rFVIIa was considered effective or partially effective based upon clinical response in 13 cases. Use was not effective in 3 cases because of a thrombotic event, no change in hemostasis, and death from bleeding complications. As thrombosis is the major safety concern, an individualized risk-benefit assessment is required prior to the use of rFVIIa therapy to restore hemostasis.

Conclusions

rFVIIa may be considered to manage major refractory bleeding from newer parenteral anticoagulant agents when the benefit is thought to outweigh the thrombotic risk.

Nanoparticles and the blood coagulation system. Part I: benefits of nanotechnology

Nanotechnology is proven to provide certain benefits in drug delivery by improving solubility, increasing uptake to target sites and changing pharmacokinetics profiles of traditional drugs. Since properties of many materials change tremendously at the nanoscale levels, nanotechnology is also being explored in various industrial applications. As such, nanoparticles are rapidly entering various areas of industry, biology and medicine. The benefits of using nanotechnology for industrial and biomedical applications are often tempered by concerns about the safety of these new materials. One such area of concern includes their effect on the immune system. While nanoparticle interactions with various constituents of the immune system have been reviewed before, little attention was given to nanoparticle effects on the blood coagulation system. Nanoparticle interface with the blood coagulation system may lead to either benefits to the host or adverse reactions. This article reviews recent advances in our understanding of nanoparticle interactions with plasma coagulation factors, platelets, endothelial cells and leukocytes. Part I is focused on desirable interactions between nanoparticles and the coagulation system, and discusses benefits of using nanotechnology to intervene in coagulation disorders. Undesirable interactions posing safety concerns are covered in part II, which will be published in the June issue of Nanomedicine.

Evaluation of recombinant factor VIIa treatment for massive hemorrhage in patients with multiple traumas

Background

Recent studies and case reports have shown that recombinant factor VIIa (rFVIIa) treatment is effective for reversing coagulopathy and reducing blood transfusion requirements in trauma patients with life-threatening hemorrhage. The purpose of this study is to evaluate the effect of rFVIIa treatment on clinical outcomes and cost effectiveness in trauma patients.

Methods

Between January 2007 and December 2010, we reviewed the medical records of patients who were treated with rFVIIa (N=18) or without rFVIIa (N=36) for life-threatening hemorrhage due to multiple traumas at the Emergency Department of Pusan National University Hospital in Busan, Korea. We reviewed patient demographics, baseline characteristics, initial vital signs, laboratory test results, and number of units transfused, and then analyzed clinical outcomes and 24-hr and 30-day mortality rates. Thromboembolic events were monitored in all patients. Transfusion costs and hospital stay costs were also calculated.

Results

In the rFVIIa-treated group, laboratory test results and clinical outcomes improved, and the 24-hr mortality rate decreased compared to that in the untreated group; however, 30-day mortality rate did not differ between the groups. Thromboembolic events did not occur in both groups. Transfusion and hospital stay costs in the rFVIIa-treated group were cost effective; however, total treatment costs, including the cost of rFVIIa, were not cost effective.

Conclusions

In our study, rFVIIa treatment was shown to be helpful as a supplementary drug to improve clinical outcomes and reduce the 24-hr mortality rate, transfusion and hospital stay costs, and transfusion requirements in trauma patients with life-threatening hemorrhage.

Cost-effectiveness of using recombinant activated factor VII as an off-label rescue treatment for critical bleeding requiring massive transfusion

BACKGROUND

Recombinant activated factor VII (rFVIIa) is widely used as an off-label rescue treatment for patients with nonhemophilic critical bleeding.

STUDY DESIGN AND METHODS

Using data from the intensive care unit, transfusion service, and death registry, the long-term survival after using rFVIIa and the associated cost per life-year gained in a consecutive cohort of patients with critical bleeding requiring massive transfusion (≥ 10 red blood cell [RBC] units in 24 hr) were assessed. rFVIIa was only used as a lifesaving treatment when conventional measures had failed.

RESULTS

Of the 353 patients with critical bleeding requiring massive transfusion, 81 (23%) required rFVIIa as a lifesaving rescue treatment. The patients requiring rFVIIa received a greater number of transfusions (number of units: RBCs, 18 vs. 12; fresh-frozen plasma, 16 vs. 10; platelets, 4 vs. 2; p < 0.001) and had a shorter survival time (24 months vs. 33 months; p = 0.002) than those who did not require rFVIIa. The total cost per life-year gained of massive transfusion and incremental cost of rFVIIa as a lifesaving treatment were US$1,148,000 (£711,760; 95% confidence interval [CI], US$825,000-US$1,471,000) and US$736,000 (£456,320; 95% CI, US$527,000-US$945,000), respectively. The incremental costs of rFVIIa increased with severity of illness and transfusion requirement and were greater than the usual acceptable cost-effective limit (<US$100,000 per life-year) for most patients with critical bleeding.

CONCLUSIONS

As a lifesaving treatment for critical bleeding, the incremental cost of rFVIIa was high. Careful patient selection is critical to balance the potential benefits of rFVIIa in an individual patient against the cost to the community.

Perioperative coagulation management--fresh frozen plasma

Clinical studies support the use of perioperative fresh frozen plasma (FFP) in patients who are actively bleeding with multiple coagulation factor deficiencies and for the prevention of dilutional coagulopathy in patients with major trauma and/or massive haemorrhage. In these settings, current FFP dosing recommendations may be inadequate. However, a substantial proportion of FFP is transfused in non-bleeding patients with mild elevations in coagulation screening tests. This practice is not supported by the literature, is unlikely to be of benefit and unnecessarily exposes patients to the risks of FFP. The role of FFP in reversing the effects of warfarin anticoagulation is dependent on the clinical context and availability of alternative agents. Although FFP is commonly transfused in patients with liver disease, this practice needs broad reconsideration. Adverse effects of FFP include febrile and allergic reactions, transfusion-associated circulatory overload and transfusion-related acute lung injury. The latter is the most serious complication, being less common with the preferential use of non-alloimmunised, male-donor predominant plasma. FP24 and thawed plasma are alternatives to FFP with similar indications for administration. Both provide an opportunity for increasing the safe plasma donor pool. Although prothrombin complex concentrates and factor VIIa may be used as alternatives to FFP in a variety of specific clinical contexts, additional study is needed.

Correction of coagulation in dilutional coagulopathy: use of kinetic and capacitive coagulation assays to improve hemostasis

The management of dilutional coagulopathy due to fluid infusion and massive blood loss is a topic that deserves a biochemical approach. In this review article, we provide an overview of current guidelines and recommendations on diagnosis and on management of transfusion in acquired coagulopathy. We discuss the biochemical differences between kinetic clotting assays (clotting times) and new capacitive coagulation measurements that provide time-dependent information on thrombin generation and fibrin clot formation. The available evidence suggests that a combination of assay types is required for evaluating new transfusion protocols aimed to optimize hemostasis and stop bleeding. Although there is current consensus on the application of fresh frozen plasma to revert coagulopathy, factor concentrates may appear to be useful in the future.

Insertion of Intracranial Pressure Monitors in Fulminant Hepatic Failure Patients

BACKGROUND

Cerebral edema contributes to the high morbidity and mortality of fulminant hepatic failure (FHF).

OBJECTIVE

We report the results of our early experience with insertion of intraparenchymal intracranial pressure (ICP) monitors in these highly coagulopathic patients.

METHODS

Eleven consecutive patients with FHF met the criteria for invasive ICP monitoring. Recombinant activated factor VII (rFVIIa) was administered at an average dose of 3 mg intravenous bolus (average, 36.7 μg/kg). We inserted the intraparenchymal ICP monitor within 15 minutes to 2 hours after rFVIIa administration, without waiting for the repeat coagulation results. Postprocedure computed tomographic scans of the brain were obtained in all patients.

RESULTS

No hemorrhagic complications were detected on the immediate postprocedure computed tomographic scans. There were no thrombotic complications in this group of patients.

CONCLUSION

In this group of patients with FHF, placement of an ICP monitor without hemorrhagic or thrombotic complications was feasible after administration of rFVIIa. This is a report of our early experience, and caution is advised. Further collaborative randomized studies are needed to prove the efficacy, optimal dosing, and cost effectiveness of rFVIIa for the placement of ICP monitors in this group of patients.

Synthesis and characterization of recombinant factor VIIa-conjugated magnetic iron oxide nanoparticles for hemophilia treatment

Maghemite (gamma-Fe(2)O(3)) nanoparticles of 15.0 +/- 2.1 nm in diameter were prepared by nucleation, followed by controlled growth of magnetic iron oxide thin films onto gelatin nuclei. Functionalization of these magnetic nanoparticles with activated double bonds was accomplished by interacting divinyl sulfone with the gelatin coating of the gamma-Fe(2)O(3) nanoparticles. The activated double bonds were then used for covalent binding, via Michael addition reaction, of recombinant factor VIIa and human serum albumin to the surface of these nanoparticles. Recombinant factor VIIa was also physically bound to the magnetic nanoparticles by interacting this factor with the human serum albumin conjugated gamma-Fe(2)O(3) nanoparticles. The influence of factor VIIa concentration on the immobilization yield has been elucidated. Leakage of the bound factor VIIa into PBS containing 4% albumin was insignificant. The coagulant activity of the physically adsorbed recombinant factor VIIa was similar to that of the free one and was significantly better than that of the covalently bound. The blood half-life of free factor VIIa is short, about 2-3 h, because of digestion by proteolytic enzymes and inhibitory effects. Stabilization of factor VIIa against trypsin (a model proteolytic enzyme) and chloromethyl ketone-type inhibitor was accomplished by conjugation of the factor to the gamma-Fe(2)O(3) nanoparticles. This stabilization may extend the blood half-life of factor VIIa. Therefore, IV injection of factor VIIa conjugated gamma-Fe(2)O(3) nanoparticles instead of free factor may avoid the frequent dosing and reduce the cost of hemophilia treatment.

Recombinant activated factor VII for massive hemoptysis in patients with cystic fibrosis

Massive hemoptysis is a common complication in patients with cystic fibrosis (CF) and is associated with significant morbidity and mortality. Conventional treatment with antibiotic therapy and early bronchial artery embolization (BAE) is usually successful in achieving hemostasis in the majority of patients. Recombinant activated factor VII (rFVIIa), originally developed for use in patients with hemophilia, has emerged as a general hemostatic agent that is potentially useful in the management of many life-threatening bleeding conditions. In this article, we present four patients with CF lung disease and massive hemoptysis who were treated successfully with rFVIIa. We suggest that in patients with CF who present with massive hemoptysis, the use of rFVIIa can be considered in patients with refractory hemoptysis despite conventional therapy or as a temporizing therapy when BAE is not immediately available.

Blood conservation strategies in pediatric anesthesia

Management of bleeding in the neonate, infant, or child presents its own set of dilemmas and challenges. One of the primary problems is the lack of good scientific evidence regarding the best management strategies for children rather than for adults. The key to success in the predicament is firstly to ensure that the physician has a clear understanding of the underlying normal physiology of the young child's hematologic status. Then by adding knowledge of the abnormal pathology that is being presented, the physician can at least understand what anomalies he or she is facing. Once all the available information concerning the patient's clinical condition and the options available has been well digested, a multidisciplinary approach allows the optimal use of all available resources. Good teamwork, understanding, and communication between all vested parties allows for a synergistic relationship to enhance patient care and give the best available end result.

Bench-to-bedside review: latest results in hemorrhagic shock

Hemorrhagic shock is a leading cause of death in trauma patients worldwide. Bleeding control, maintenance of tissue oxygenation with fluid resuscitation, coagulation support, and maintenance of normothermia remain mainstays of therapy for patients with hemorrhagic shock. Although now widely practised as standard in the USA and Europe, shock resuscitation strategies involving blood replacement and fluid volume loading to regain tissue perfusion and oxygenation vary between trauma centers; the primary cause of this is the scarcity of published evidence and lack of randomized controlled clinical trials. Despite enormous efforts to improve outcomes after severe hemorrhage, novel strategies based on experimental data have not resulted in profound changes in treatment philosophy. Recent clinical and experimental studies indicated the important influences of sex and genetics on pathophysiological mechanisms after hemorrhage. Those findings might provide one explanation why several promising experimental approaches have failed in the clinical arena. In this respect, more clinically relevant animal models should be used to investigate pathophysiology and novel treatment approaches. This review points out new therapeutic strategies, namely immunomodulation, cardiovascular maintenance, small volume resuscitation, and so on, that have been introduced in clinics or are in the process of being transferred from bench to bedside. Control of hemorrhage in the earliest phases of care, recognition and monitoring of individual risk factors, and therapeutic modulation of the inflammatory immune response will probably constitute the next generation of therapy in hemorrhagic shock. Further randomized controlled multicenter clinical trials are needed that utilize standardized criteria for enrolling patients, but existing ethical requirements must be maintained.