The use of recombinant factor VIIa in liver diseases

Clinical Outcomes of a Pharmacy-Led Blood Factor Stewardship Program

To report the results of a pharmacist-directed blood factor stewardship program targeting off-label utilization designed to limit use to established organizational guidelines in high-risk populations. Prospective evaluation of recombinant factor VIIa and prothrombin complex concentrate orders beginning June 2013 through May 2014 and a matched retrospective cohort from June 2012 to May 2013. Matched cohorts were evaluated for 28-day mortality, change in international normalized ratio (INR), adverse events, concurrent blood product use, and cost savings. Forty-two orders for blood factor were ordered between June 2013 and May 2014, 70 orders in the year before (N = 112). Twenty eight-day mortality was not different between the cohorts: 53.9% versus 50% (P = 0.77). Blood factor use with underlying liver failure and active bleeding was strongly associated with 28-day mortality: odds ratio (95% confidence interval), 2.9 (1.5-7.14) and 2.91 (0.01-2.91), respectively. Blood products dispensed increased over the year with plasma products the most significant (1 vs. 4 P = 0.004). All other clinical outcomes were nonsignificant. An annual cost savings of $375,539 was achieved, primarily through a significant reduction in recombinant factor VIIa and avoidance in high-risk patients. Use of off-label blood factors can be controlled through a pharmacist-led stewardship program. Twenty eight-day mortality was not different between the 2 cohorts; however, identification of risk factors for death associated with blood factor use allows for restriction in high-risk populations, creates a discussion of futile care, and yields cost savings.

Hemostasis, bleeding and thrombosis in liver disease

The presence of cirrhosis poses an increased risk of both thrombosis and bleeding in individuals with chronic liver disease. This duality is a result of a dynamic disequilibrium between procoagulant and anticoagulant states in individuals with cirrhosis. The mechanism of this imbalance in cirrhosis remains unclear. It is known that the progression of cirrhosis leads to decreased synthetic function and a concurrent lack of natural anticoagulants. Other proposed mechanisms contributing to this hemostatic imbalance include decreased platelet production, increased platelet destruction from hypersplenism, decreased synthesis of Vitamin K-dependent and independent clotting factors and anticoagulant factors, and alterations in purinergic signaling pathways.

Given the current state of flux in our understanding of bleeding and thrombophilia in cirrhosis, the recommendations for treatment of these conditions are still evolving.

We provide a current update on the proposed pathophysiology of altered hemostasis and thrombophilia in cirrhosis. We discuss recent studies in portal vein thrombosis (PVT) and venous thromboembolism (VTE), which are the common thrombotic consequences of cirrhosis, resulting in substantive morbidity and mortality. To address these, we discuss new prophylactic interventions and current treatment options to manage the heightened risk of thrombosis in cirrhosis, while limiting hemorrhagic complications.

Recombinant activated factor VII in patients with acute liver failure with UNOS Status 1A: a single tertiary academic centre experience

BACKGROUND AND OBJECTIVES

Recombinant activated factor VII (rFVIIa) is often used in off-label indications, including many situations in which the patients are at risk of thrombosis. In this study, we retrospectively reviewed the use of rFVIIa in patients with acute liver failure - UNOS Status 1A (ALF-1A) to determine its efficacy and safety profile.

MATERIALS AND METHODS

Using the transplantation records, all adult patients with ALF-1A were identified from 6/2001 to 3/2009. From patients' medical charts, rFVIIa dose, blood component usage, short-term outcomes [length of intensive care unit (ICU) and hospital stay, ability to undergo orthotopic liver transplant (OLT) and in-hospital survival rate] and adverse events were examined.

RESULTS

Forty-two patients with ALF-1A were identified. Fifteen patients received rFVIIa with doses ranging between 24·4 μg/kg and 126·8 μg/kg. Three patients received two doses of rFVIIa. The age, baseline activated partial thromboplastin time (aPTT) and platelet (PLT) count were not statistically different between the group receiving rFVIIa versus the group that did not. However, the prothrombin time (PT) was significantly higher in the rFVIIa group. Although the rFVIIa group stayed in the ICU longer and required significant more blood products during admission, there was no statistical difference between the two groups in terms of length of hospital stay, ability to undergo OLT and survival rate. There was no increase in complications, including thrombosis, after receiving rFVIIa.

CONCLUSION

Recombinant activated factor VII (rFVIIa) appears to be safe in patients with ALF-1A, but to elucidate its full role, a randomized controlled trial would be ideal.

Preliminary experience with use of recombinant activated factor VII to control postpartum hemorrhage in acute fatty liver of pregnancy and other pregnancy-related liver disorders

Control of postpartum hemorrhage is difficult in patients with coagulopathy due to acute liver failure. Recombinant activated factor VII (rFVIIa) can help in control of bleed; however, it has short duration of action (2-4 h). The study aimed to report the use of rFVIIa in this setting. We retrospectively analyzed all patients with acute liver failure secondary to pregnancy-related liver disorders who received rFVIIa for control of postpartum hemorrhage (six patients, all six met diagnostic criteria for acute fatty liver of pregnancy). One dose of rFVIIa achieved adequate control of bleeding in five patients, while one patient needed a second dose. rFVIIa administration corrected coagulopathy and significantly reduced requirement of packed red cells and other blood products. No patient had thrombotic complications. In conclusion, rFVIIa was a useful adjunct to standard management in postpartum hemorrhage secondary to acute liver failure of pregnancy-related liver disorders.

Approach to a child with bleeding in the emergency room

A bleeding child is a cause of great concern and often, panic, for parents and pediatricians alike. Causes of bleeding could be trivial or secondary to an underlying bleeding disorder or a potentially serious systemic illness. Based on etiology, they can be categorized into disorders affecting platelets or the coagulation cascade and can be inherited or acquired. A systematic approach with relevant clinical history and examination along with appropriate laboratory investigations aid in reaching the diagnosis promptly. Indication and administration of blood products including fresh frozen plasma, cryoprecipitate, random donor and single donor apheresis platelets is elaborated. Management of hemophilia, Von Willebrand disease, disseminated intravascular coagulation and bleeding in cyanotic congenital heart disease, among other causes is outlined. Role of antifibrinolytic therapy, desmopressin and recombinant factor VIIa is briefly described. The review outlines the approach to a bleeding child in the emergency room. Practical points in history, examination, investigations and management are discussed. Management in resource constraint setting of developing countries is addressed.

Surgery in a patient with liver disease

Surgery is often needed in patients with concurrent liver disease. The multiple physiological roles of the liver places these patients at an increased risk of morbidity and mortality. Diseases necessitating surgery like gallstones and hernia are more common in patients with cirrhosis. Assessment of severity of liver dysfunction before surgery is important and the risk benefit of the procedure needs to be carefully assessed. The disease severity may vary from mild transaminase rise to decompensated cirrhosis. Surgery should be avoided if possible in the emergency setting, in the setting of acute and alcoholic hepatitis, in a patient of cirrhosis who is child class C or has a MELD score more than 15 or any patient with significant extrahepatic organ dysfunction. In this subset of patients, all possible means to manage these patients conservatively should be attempted. Modified Child-Pugh scores and model for end-stage liver disease (MELD) scores can predict mortality after surgery fairly reliably including nonhepatic abdominal surgery. Pre-operative optimization would include control of ascites, correction of electrolyte imbalance, improving renal dysfunction, cardiorespiratory assessment, and correction of coagulation. Tests of global hemostasis like thromboelastography and thrombin generation time may be more predictive of the risk of bleeding compared with the conventional tests of coagulation in patients with cirrhosis. Correction of international normalized ratio with fresh frozen plasma does not necessarily mean reduction of bleeding risk and may increase the risk of volume overload and lung injury. International normalized ratio liver may better reflect the coagulation status. Recombinant factor VIIa in patients with cirrhosis needing surgery needs further study. Intra-operatively, safe anesthetic agents like isoflurane and propofol with avoidance of hypotension are advised. In general, nonsteroidal anti-inflammatory drug (NSAIDs) and benzodiazepines should not be used. Intra-abdominal surgery in a patient with cirrhosis becomes more challenging in the presence of ascites, portal hypertension, and hepatomegaly. Uncontrolled hemorrhage due to coagulopathy and portal hypertension, sepsis, renal dysfunction, and worsening of liver failure contribute to the morbidity and mortality in these patients. Steps to reduce ascitic leaks and infections need to be taken. Any patient with cirrhosis undergoing major surgery should be referred to a specialist center with experience in managing liver disease.

Coagulation in hepatobiliary disease

OBJECTIVE

To review the pathogenesis and clinical consequences of coagulation abnormalities accompanying hepatobiliary disorders and to highlight the need for further studies to characterize these derangements and their treatment options in small animal patients.

DATA SOURCES

Veterinary and human medical literature: original research articles, scientific reviews, consensus statements, and recent texts.

SUMMARY

The liver plays an important role in the production and clearance of many components of coagulation. A wide range of hemostatic derangements can occur in patients with hepatobiliary disease including alterations in platelet number and function, coagulation factor levels, anticoagulants, vascular endothelial function, and fibrinolysis. As these hemostatic alterations include both pro- and anticoagulation pathways, the net result is often a rebalanced hemostatic system that can be easily disrupted by concurrent conditions resulting in either clinical bleeding or thrombosis. Conventional coagulation tests are inadequate at identifying the spectrum of coagulation alterations occurring in patients with hepatobiliary disease, but their evaluation is necessary to assess bleeding risk and provide prognostic information. A paucity of information exists regarding the treatment of the coagulation derangements in small animals with hepatobiliary disease. Extrapolation from human studies provides some information about potential treatment options, but further studies are warranted in this area to elucidate the best management for coagulation abnormalities in dogs and cats with hepatobiliary disease.

CONCLUSION

Hepatobiliary disease can have profound effects on coagulation function leading to hypercoagulable or hypocoagulable states. Overall coagulation status with hepatobiliary disease depends on both the type and severity of disease and the presence of associated complications.

Human recombinant activated factor VII for upper gastrointestinal bleeding in patients with liver diseases

BACKGROUND

Mortality from upper gastrointestinal bleeding in patients with liver disease is high. Recombinant human activated factor VII (rHuFVIIa) has been suggested for patients with liver disease and upper gastrointestinal bleeding.

OBJECTIVES

To assess the beneficial and harmful effects of rHuFVIIa in patients with liver disease and upper gastrointestinal bleeding.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register (December 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 4, 2011), MEDLINE (1948 to December 2011), EMBASE (1980 to December 2011), Science Citation Index Expanded (1900 to December 2011), and LILACS (December 2011). We sought additional randomised trials from the reference lists of the trials and reviews identified through the electronic searches.

SELECTION CRITERIA

Randomised clinical trials.

DATA COLLECTION AND ANALYSIS

Outcome data from randomised clinical trials were extracted and were presented using random-effects model meta-analyses. Data on the risk of bias in the included trials were also extracted.

MAIN RESULTS

We included two trials with 493 randomised participants with various Child-Pugh scores. The trials had a low risk of bias. The rHuFVIIa administration did not reduce the risk of mortality within five days (21/288 (7.3%) versus 15/205 (7.3%); risk ratio (RR) 0.88, 95% confidence interval (CI) 0.48 to 1.64, I(2) = 49%) and within 42 days (5/286 (1.7%) versus 36/205 (17.6%); RR 1.01, 95% CI 0.55 to 1.87, I(2) = 55%) when compared with placebo. Trial sequential analysis demonstrated that there is sufficient evidence to exclude that rHuFVIIa decreases mortality by 80%, but there is insufficient evidence to exclude smaller effects. The rHuFVIIa did not increase the risk of adverse events by number of patients (218/297 (74%) and 164/210 (78%); RR 0.94, 95% CI 0.84 to 1.04, I(2) = 1%), serious adverse events by adverse events reported (164/590 (28%) versus 123/443 (28%); RR 0.91, 95% CI 0.75 to 1.11, I(2) = 0%), and thromboembolic adverse events (16/297 (5.4%) versus 14/210 (6.7%); RR 0.80, 95% CI 0.40 to 1.60, I(2) = 0%) when compared with placebo.

AUTHORS' CONCLUSIONS

We found no evidence to support or reject the administration of rHuFVIIa for patients with liver disease and upper gastrointestinal bleeding. Further adequately powered randomised clinical trials are needed in order to evaluate the proper role of rHuFVIIa for treating upper gastrointestinal bleeding in patients with liver disease. Although the results are based on trials with low risk of bias, the heterogeneity and the small sample size result in rather large confidence intervals that cannot exclude the possibility that the intervention has some beneficial or harmful effect. Further trials with alow risk of bias are required to make more confident conclusions about the effects of the intervention.

Clinical Usefulness of Recombinant Activated Factor VII in Patients with Liver Failure Undergoing Invasive Procedures

Objective:

To evaluate the use of recombinant activated factor VII (rFVIIa) in patients with liver failure undergoing invasive procedures.

Methods:

An OVID/MEDUNE and PubMed search (1997-June 2011) was performed to identify literature on the use of rFVIIa to reduce bleeding risk in patients with liver failure undergoing invasive procedures.

Study Selection and Data Extraction:

English-language data evaluating the efficacy of rFVIIa to reverse coagulopathies prior to invasive procedures in patients with liver disease were included.

Data Synthesis:

Following administration of rFVIIa, prothrombin time (PT) and international normalized ratio (INR) response is within 30 minutes. Doses ranging from 20 to 120 μg/kg have been studied, with a reduction in PT seen in a dose-dependent manner. One study in patients with no bleeding administered 5, 20, and 80 μg/kg sequentially during a 24-day period. All doses provided reversal of prolonged PT within 10 minutes, and the duration was dose-dependent. In a study of 15 patients with fulminant liver failure, requiring intracranial pressure monitor placement, a rFVIIa dose of 40 μg/kg was compared to fresh frozen plasma. In patients who received rFVIIa, the PT and INR normalized, compared to none of the patients in the fresh frozen plasma group.

Conclusions:

Retrospective and prospective data demonstrate that rFVIIa effectively reverses elevated PT and INR, reducing the risk of bleeding and safely facilitating invasive procedures. Based on available data, a dose of 20-40 μg/kg 30 minutes prior to an invasive procedure should be considered in patients with acute or chronic liver failure at risk for bleeding complications. A major limitation of rFVIIa use is the high cost of therapy. A prospective, randomized trial could help determine the appropriate dose of rFVIIa, timing of dose in relationship to procedure, and usefulness of subsequent doses.

Proteases as therapeutics

Proteases are an expanding class of drugs that hold great promise. The U.S. FDA (Food and Drug Administration) has approved 12 protease therapies, and a number of next generation or completely new proteases are in clinical development. Although they are a well-recognized class of targets for inhibitors, proteases themselves have not typically been considered as a drug class despite their application in the clinic over the last several decades; initially as plasma fractions and later as purified products. Although the predominant use of proteases has been in treating cardiovascular disease, they are also emerging as useful agents in the treatment of sepsis, digestive disorders, inflammation, cystic fibrosis, retinal disorders, psoriasis and other diseases. In the present review, we outline the history of proteases as therapeutics, provide an overview of their current clinical application, and describe several approaches to improve and expand their clinical application. Undoubtedly, our ability to harness proteolysis for disease treatment will increase with our understanding of protease biology and the molecular mechanisms responsible. New technologies for rationally engineering proteases, as well as improved delivery options, will expand greatly the potential applications of these enzymes. The recognition that proteases are, in fact, an established class of safe and efficacious drugs will stimulate investigation of additional therapeutic applications for these enzymes. Proteases therefore have a bright future as a distinct therapeutic class with diverse clinical applications.

Recombinant factor VIIa for the prevention and treatment of bleeding in patients without haemophilia

BACKGROUND

Recombinant factor VIIa (rFVIIa) is licensed for use in patients with haemophilia and inhibitory allo-antibodies. It is also increasingly being used for off-license indications to prevent bleeding in operations where blood loss is likely to be high, and/or to stop bleeding that is proving difficult to control by other means.

OBJECTIVES

To assess the effectiveness of rFVIIa when used therapeutically to control active bleeding, or prophylactically to prevent (excessive) bleeding in patients without haemophilia.

SEARCH STRATEGY

We searched the Cochrane Injuries Group Specialised Register, CENTRAL, MEDLINE, EMBASE and other specialised databases up to 25 February 2009.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing rFVIIa with placebo, or one dose of rFVIIa with another, in any patient population (except haemophilia). Outcomes were mortality, blood loss or control of bleeding, red cell transfusion requirements, number of patients transfused and thromboembolic adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed potentially relevant studies for inclusion, extracted data and examined risk of bias. We considered prophylactic and therapeutic rFVIIa studies separately.

MAIN RESULTS

Twenty-five RCTs were included: 24 were placebo-controlled double-blind RCTs and one compared different doses of rFVIIa.Fourteen trials involving 1137 participants examined the prophylactic use of rFVIIa; 713 received rFVIIa. There was no evidence of mortality benefit (RR 1.06; 95% CI 0.50 to 2.24). There was decreased blood loss (WMD -272 mL; 95% CI -399 to -146) and decreased red cell transfusion requirements (WMD -243 mL; 95% CI -393 to -92) with rFVIIa treatment; however these values were likely overestimated due to the inability to incorporate data from trials showing no difference of rFVIIa treatment compared to placebo. There was a trend in favour of rFVIIa in the number of participants transfused (RR 0.91; 95% CI 0.82 to 1.02). But there was a trend against rFVIIa with respect to thromboembolic adverse events (RR 1.32; 95% CI 0.84 to 2.06).Eleven trials involving 2366 participants examined the therapeutic use of rFVIIa; 1507 received rFVIIa. There were no outcomes where any observed advantage, or disadvantage, of rFVIIa over placebo could not have been observed by chance alone. There was a trend in favour of rFVIIa for reducing mortality (RR 0.89; 95% CI 0.77 to 1.03). However, there was a trend against rFVIIa for increased thromboembolic adverse events (RR 1.21; 95% CI 0.93 to 1.58).

AUTHORS' CONCLUSIONS

The effectiveness of rFVIIa as a more general haemostatic drug, either prophylactically or therapeutically, remains unproven. The use of rFVIIa outside its current licensed indications should be restricted to clinical trials.

Recombinant activated factor VII in liver patients: a retrospective cohort study from Australia and New Zealand

Recombinant factor VIIa (rFVIIa) is used in the treatment of life-threatening haemorrhage that is refractory to conventional treatment. The evidence supporting this practice in patients with liver disease is very limited. It has been used as a salvage therapy in end-stage liver disease (ESLD), in orthotopic liver transplant (OLT), other surgery, and upper gastrointestinal bleeding (UGIB) subpopulations. It has also been used prior to procedures in patients with ESLD. Data were collected by the Australia and New Zealand Haemostasis Registry (ANZHR) to perform a retrospective cohort study on the different subgroups of liver patients. This included 115 cases of use of rFVIIa in liver patients from 20 hospitals. A retrospective cohort study on the different subgroups of liver patients was performed. Main outcome measures were reduction or cessation of bleeding and 28-day mortality. Variables previously shown to predict response to bleeding after administration of rFVIIa were examined to determine whether correlations exist. Salvage therapy with rFVIIa was associated with reduction or cessation in bleeding in 24 of 36 OLT patients, 24 of 36 UGIB patients and 15 of 26 of other surgery patients. Clinical response to rFVIIa in OLT patients and other surgery patients was associated with a significantly lower mortality compared to nonresponders (P = 0.003 and 0.022, respectively). There was no relationship between mortality and bleeding response in patients with UGIB. Variables including acidosis, hypothermia, hypofibrinogenaemia, thrombocytopenia and Model of End-Stage Liver Disease (MELD) score were not associated with clinical response to rFVIIa. Five cases of use prior to procedures are described. Recombinant FVIIa is used as rescue therapy in surgical patients with ESLD and refractory haemorrhage in Australia and New Zealand. Traditional haemostasis variables were not associated with clinical response to rFVIIa in this cohort. Response to rFVIIa is associated with decreased mortality in ESLD patients undergoing OLT and other surgery, but not in UGIB.

Recombinant factor VIIa for the prevention and treatment of bleeding in patients without haemophilia

BACKGROUND

Recombinant factor VIIa (rFVIIa) is licensed for use in patients with haemophilia and inhibitory allo-antibodies. It is also increasingly being used for off-license indications to prevent bleeding in operations where blood loss is likely to be high, and/or to stop bleeding that is proving difficult to control by other means.

OBJECTIVES

To assess the effectiveness of rFVIIa when used therapeutically to control active bleeding, or prophylactically to prevent (excessive) bleeding in patients without haemophilia.

SEARCH STRATEGY

We searched the Cochrane Injuries Group's Specialised Register, CENTRAL, MEDLINE, EMBASE and other specialised databases up to March 2006. We also searched reference lists of articles and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing rFVIIa with placebo, or one dose of rFVIIa with another, in any patient population with the exception of those with haemophilia. There was no restriction by outcomes examined, but this review focuses on mortality, blood loss or control of bleeding, red cell transfusion requirements, number of patients transfused and thromboembolic adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed potentially relevant studies for inclusion. Data were extracted and methodological quality was examined. Studies using rFVIIa prophylactically and those using rFVIIa therapeutically have been considered separately. Data were pooled using fixed and random effects models, but random effects models were preferred because of the variability in clinical features of the included studies.

MAIN RESULTS

Thirteen trials met the inclusion criteria; all were placebo-controlled double-blind RCTs. Six trials involving 724 participants examined the prophylactic use of rFVIIa; 379 received rFVIIa. There were no outcomes by which any observed advantage, or disadvantage, of rFVIIa over placebo could not have been observed by chance alone. There were trends in favour of rFVIIa for a number of outcomes, particularly the number of participants transfused, pooled RR 0.85 (95% CI 0.72 to 1.01) but this was balanced by a trend against rFVIIa with respect to thromboembolic adverse events, pooled RR 1.25 (95% CI 0.76 to 2.07). Seven trials involving 1214 participants examined the therapeutic use of rFVIIa; 687 received rFVIIa. There were no outcomes where any observed advantage, or disadvantage, of rFVIIa over placebo could not have been observed by chance alone. There was a trend in favour of rFVIIa for reducing mortality, RR 0.82 (95% CI 0.64 to 1.04), although no other clear trends in favour of rFVIIa were noted for other desired outcomes. Interpretation of these results must take into account one study which could not be included in the quantitative summary but which showed results strongly in favour of rFVIIa for the treatment of intra-cerebral haemorrhage. There was a trend against rFVIIa with respect to thromboembolic adverse events; the RR 1.50 (95% CI 0.86 to 2.62).

AUTHORS' CONCLUSIONS

Although rFVIIa has a role in the management of patients with haemophilia, its effectiveness as a more general haemostatic drug, either prophylactically or therapeutically, remains uncertain. Its effectiveness as a therapeutic agent, particularly for intra-cerebral haemorrhage, looks more encouraging than prophylactic use. The use of rFVIIa outside its current licensed indications should be very limited and its wider use await the results of ongoing and possibly newly commissioned RCTs. In the interim, rFVIIa use should be restricted to clinical trials.