Treatment of intracranial hemorrhage

Abstract

This disclosure relates to compositions and methods for improving hemostatic efficacy in patients with intracranial hemorrhage during anticoagulation therapy with factor Xa (FXa) inhibitors. In some embodiments, the patient is selected if they exhibit a high hematoma growth rate and / or high diastolic blood pressure.

Description

Cross-reference to related applications

[0001] This application claims the benefits of U.S. Provisional Application No. 63 / 589,271, filed October 10, 2023; U.S. Provisional Application No. 63 / 597,881, filed November 10, 2023; U.S. Provisional Application No. 63 / 650,850, filed May 22, 2024; and U.S. Provisional Application No. 63 / 688,784, filed August 29, 2024, all of which are incorporated herein by reference in their entirety. Background Technology

[0002] Factor Xa inhibitors, such as apixaban, rivaroxaban, edoxaban, betraxaban, and enoxaparin, have a positive benefit-risk profile for the treatment and prevention of thrombotic events, but may cause or exacerbate acute massive bleeding with significant morbidity and mortality. Due to the lack of specific reversal agents, factor Xa inhibitor-related acute massive bleeding events may be difficult to treat.

[0003] Andexanet alfa (recombinant inactivated factor Xa-zhzo) is a modified recombinant inactive form of factor Xa specifically designed to bind to and insulate factor Xa inhibitor molecules, thereby rapidly reducing anti-factor Xa activity (a measure of the anticoagulant effect of factor Xa inhibitors). In healthy subjects receiving apixaban or rivaroxaban, andexanet rapidly reduced the unbound portion of factor Xa inhibitors and anti-factor Xa activity with minimal adverse effects. Summary of the Invention

[0004] This disclosure relates to compositions and methods for improving hemostatic efficacy in patients with intracranial hemorrhage during anticoagulation therapy with factor Xa (FXa) inhibitors.

[0005] One embodiment of this disclosure provides a method for improving hemostatic efficacy in a patient with intracranial hemorrhage during anticoagulation therapy with a factor Xa (FXa) inhibitor, comprising administering an FXa derivative to the patient, the FXa derivative being missing at least 50% of amino acid residues 6-39 of its light chain and having its active site on the heavy chain modified, wherein the FXa derivative exhibits reduced catalytic activity compared to wild-type FXa protein and is capable of binding the factor Xa inhibitor.

[0006] In some implementations, the factor Xa inhibitor is a direct factor Xa inhibitor, such as apixaban and rivaroxaban.

[0007] In some implementations, the administration is performed within 6 hours of the onset of symptoms of intracranial hemorrhage, or preferably within 3 hours of the onset of symptoms of intracranial hemorrhage.

[0008] In some embodiments, the administration is performed within 15 hours after the patient takes the FXa inhibitor. In some embodiments, the administration comprises a bolus injection of the FXa derivative. In some embodiments, the bolus injection contains 300-500 mg of the FXa derivative, or preferably 350-450 mg of the FXa derivative.

[0009] In some embodiments, the administration further includes infusion of the FXa derivative following the bolus injection. In some embodiments, the infusion comprises 400-560 mg of the FXa derivative, or preferably 450-510 mg of the FXa derivative.

[0010] In some embodiments, the anticoagulation therapy comprises 10 mg or less rivaroxaban, 5 mg or less apixaban, 30 mg or less edoxaban, or 40 mg or less enoxaparin. In some embodiments, the anticoagulation therapy comprises 10 mg or less rivaroxaban, or 5 mg or less apixaban.

[0011] In some implementations, the patient is at least 75 years old. In some implementations, the patient's baseline NIHSS (NIH Stroke Scale / Score) is greater than 9.

[0012] In some embodiments, the FXa derivative is a double-chain protein comprising a light chain containing the amino acid sequence of SEQ ID NO:3 or having at least 85% sequence identity with a first peptide of SEQ ID NO:3, and a heavy chain containing the amino acid sequence of SEQ ID NO:4 or having at least 85% sequence identity with a second peptide of SEQ ID NO:4. In some embodiments, the FXa derivative is andexanet alfa. Attached Figure Description

[0013] The accompanying drawings provided as embodiments of this disclosure are illustrative by way of example only and not by way of limitation, wherein:

[0014] Figure 1The decrease in median antiFXa activity from baseline to the 2-hour nadir is shown. The median value, along with Q1 (low bars) and Q3 (high bars), is plotted in the figure. Non-missing values ​​at baseline, 1 hour, and 2 hours after randomization are summarized. Participants with missing baseline antiFXa activity values ​​were excluded from the analysis. P-values ​​were derived from SAP. ANCOVA based on the percentage change from the nadir in rank was used to compare andexanet and UC using multiple imputation schemes based on missing values ​​at 1 hour and 2 hours after randomization, adjusted for the time from symptom onset to baseline imaging (< 180 minutes vs. ≥ 180 minutes) and baseline antiFXa activity covariates. The imputation process was run 100 times, producing a set of 100 p-values, with the final p-value obtained using the median p-value rule.

[0015] Figure 2 Forest plots showing selected subgroups of hemostatic efficacy are presented. Abbreviations: AF = Atrial fibrillation, CI = Confidence interval, FXa = Factor Xa inhibitor, NIHSS = National Institutes of Health Stroke Scale, MI = Myocardial infarction, PCC = Prothrombin complex concentrate. For subgroup analysis, the increase in andexanet per 100 patients, with 95% CI, was derived from a Cochran-Mantel-Haenszel (CMH) test stratified by time from symptom onset to baseline imaging (<180 minutes vs. ≥180 minutes). p-values ​​for interactions were obtained via logistic regression, with covariates including treatment, grouping variable, treatment-group interaction, and time from symptom onset to baseline imaging (<180 minutes vs. ≥180 minutes). 3: * indicates exploratory subgroup. 4. **Excludes 139 patients randomized prior to Amendment 1.

[0016] Figure 3 A forest plot showing selected subgroups of thrombotic events is presented. Abbreviations: AF = Atrial fibrillation, CI = Confidence interval, FXa = Factor Xa inhibitor, NIHSS = National Institutes of Health Stroke Scale, MI = Myocardial infarction, PCC = Prothrombin complex concentrate. The increase in risk of thrombotic events per 100 patients in andexanet is estimated based on proportional differences, with 95% CI being Wald CI. If the total number of events in both groups is less than 5, the increased risk and 95% CI are not reported. 3. The p-value for the interaction was obtained by logistic regression, with covariates being treatment, grouping variables, and the treatment-grouping interaction. 4: * indicates an exploratory subgroup. 5. **Excludes the 139 patients randomized prior to Amendment 1.

[0017] Figure 4This is a line graph of anti-FXa activity in the overall patient population, grouped by treatment. The time progression of anti-FXa activity is shown as the mean and standard error at each time point. Patients who previously used enoxaparin as a factor Xa inhibitor were excluded because the units of anti-FXa activity could not be converted. FXa, Activated Factor X; ITT, Intention to Treatment; SE, Standard Error.

[0018] Figure 5A -C is a line graph of antiFXa activity by treatment group in patients taking apixaban (A), rivaroxaban (B), and edoxaban (C). The time progression of antiFXa activity is shown as the mean and standard error at each time point.

[0019] Figure 6A This model shows the likelihood of hematoma enlargement (≥12.5 mL or ≥35%) based on baseline hematoma volume (mL) and treatment group. Variables in the model: treatment, baseline hematoma volume.

[0020] Figure 6B This model shows the likelihood of hematoma enlargement (≥12.5 mL or ≥35%) based on the time from symptom onset to treatment (hours) and the treatment group. Variables in the model: treatment, time from symptom onset to treatment.

[0021] Figure 6C This model shows the likelihood of hematoma expansion (≥12.5 mL or ≥35%) based on baseline anti-FXa levels (ng / mL) and treatment group. Variables in the model: treatment, baseline anti-FXa level.

[0022] Figure 6D This model shows the likelihood of hematoma enlargement (≥12.5 mL or ≥35%) based on the pre-scan hematoma growth rate (mL / hour) and the treatment group. Variables in the model: treatment, pre-scan hematoma growth rate.

[0023] Figure 6E This model shows the likelihood of hematoma enlargement (≥12.5 mL or ≥35%) based on diastolic blood pressure (mm Hg) and treatment group. Variables in the model: treatment, baseline diastolic blood pressure.

[0024] Figure 7 This describes the proposed "11-to-1 rule" for individualized andexanet treatment decisions in patients with acute FXa inhibitor-associated ICH. Abbreviations: HE, hematoma expansion; hr, hours; ICH, intracerebral hemorrhage; MI, myocardial infarction; NNH, number of patients requiring injury; NNT, number of patients requiring treatment; TE, thrombotic event. Detailed Implementation I. Definition

[0025] All numerical designations, such as pH, temperature, time, concentration, and molecular weight, including ranges, are approximate values ​​in increments of 0.1 (+) or (-). It should be understood that, although not always explicitly stated, all numerical designations are preceded by the term "approximately." It should also be understood that, although not always explicitly stated, the reagents described herein are exemplary only, and their equivalents are known in the art.

[0026] "Composition" is intended to mean a combination of an active agent with another compound or composition (inert (e.g., a detectable reagent or label) or active).

[0027] "Factor Xa," ​​or "FXa," or "FXa protein" is a serine protease in the blood clotting pathway, produced by inactive factor X (fX). The nucleotide sequence encoding human factor X ("fX") can be found in GenBank under accession number "NM_000504." Following catalytic cleavage of the first 52 residues of the heavy chain, fX is activated to FXa (SEQ ID NO. 1, Table 1). FXa comprises a light chain and a heavy chain (as shown in Table 1). The first 45 amino acid residues of the light chain (residues 1-45 of SEQ ID NO. 1) are called the Gla domain because it contains 11 post-translational modified γ-carboxyglutamic acid residues (Gla). It also contains a short (6 amino acid residues) aromatic stacked sequence (residues 40-45 of SEQ ID NO. 1). Chymotrypsin digestion selectively removes residues 1-44, producing FXa without the Gla domain. The serine protease catalytic domain of FXa is located on the C-terminal heavy chain. The heavy chain of FXa is highly homologous to other serine proteases such as thrombin, trypsin, and activator protein C.

[0028] "Natural FXa" or "wild-type FXa" refers to FXa that is naturally present in plasma or isolated in its original, unmodified form, possessing the biological activity of activating prothrombin and thus promoting blood clot formation. This term includes naturally occurring peptides isolated from tissue samples as well as recombinant FXa. "Active FXa" refers to FXa possessing the biological activity of activating prothrombin. "Active FXa" can be natural FXa or modified FXa that retains its procoagulant activity.

[0029] As used herein, “FXa derivative” refers to a modified FXa protein having a modified or substantially absent Gla domain (e.g., at least 50%, 60%, 70%, 80%, or 90% of amino acid residues 6–39 of the light chain) and a modified active site such that, compared to the wild-type protein, the FXa derivative has a reduced ability to assemble into the prothrombinase complex and reduced or no catalytic activity. Nevertheless, similar to the wild-type protein, the FXa derivative can bind to and / or substantially neutralize FXa inhibitors. Examples of FXa derivatives are provided in WO2009 / 042962 and WO2010 / 117729 and their bioequivalents.

[0030] The term "active site" refers to the portion of an enzyme or antibody where a chemical reaction occurs. A "modified active site" is an active site that has been structurally modified to provide an active site with increased or decreased chemical reactivity or specificity. Examples of active sites include, but are not limited to, the catalytic domain of human factor X containing amino acid residues 235-488, and the catalytic domain of human factor Xa containing amino acid residues 195-448. Examples of modified active sites include, but are not limited to, the catalytic domain of human factor Xa containing amino acid residues 195-448 of SEQ ID NO. 2 and having at least one amino acid substitution at Arg306, Glu310, Arg347, Lys351, Lys414, or Arg424.

[0031] An example of an FXa derivative is "Gla-free FXa" or "des-Gla FXa," which refers to FXa or FXa derivatives that do not have a Gla domain, and encompasses FXa derivatives with modifications other than the removal of the Gla domain. Examples of Gla-free FXa in this invention include, but are not limited to, FXa derivatives that lack all or part of the amino acid residues at positions 1-39 (or 6-39) of SEQ ID NO. 1.

[0032] Another example of Xa factor derivatives is "Gla-deficient FXa," which refers to FXa or FXa derivatives with a reduced number of free γ-carboxyl groups in their Gla domain. Like FXa without a Gla domain, Gla-deficient FXa can also have other modifications. Gla-deficient FXa includes uncarboxylated, undercarboxylated, and decarboxylated FXa. "Uncarboxylated FXa" or "decarboxylated FXa" refers to FXa derivatives that lack the γ-carboxyl glutamate residues in the Gla domain, such as FXa where all Gla domain γ-carboxyl glutamates are replaced by different amino acids, or FXa where all side-chain γ-carboxyl groups are removed or masked by means such as amination, esterification, etc. For recombinantly expressed proteins, uncarboxylated FXa is sometimes also called non-carboxylated FXa. "Insufficiently carboxylated FXa" refers to FXa derivatives that have a reduced number of γ-carboxyl groups in the Gla domain compared to wild-type FXa, such as FXa in which one or more, but not all, of the γ-carboxyglutamic acid groups in the Gla domain are replaced by one or more different amino acids, or FXa in which at least one, but not all, of the γ-carboxyl groups in the side chain are removed or masked by means such as amination and esterification.

[0033] In some embodiments, the FXa derivative is missing at least amino acid residues 6-39 of the wild-type FXa light chain (see the light chain in SEQ ID NO:1). In some embodiments, the Xa factor derivative is also missing the EGF1 domain (amino acids 46-84) and / or the EGF2 domain (amino acids 85-128 of the light chain). In some embodiments, the light chain of the Xa factor derivative contains at least amino acids 129-139 of the wild-type light chain (or amino acids 95-105 of SEQ ID NO:3).

[0034] SEQ ID NO: 2 (Table 2), also known as “andexanet alfa” or simply “andexanet”, contains two mutations relative to wild-type FXa. The first mutation is the deletion of amino acid residues 6-39 of the fX Gla domain. The second mutation is the replacement of the active site residue S379 with the Ala residue. This amino acid substitution corresponds to amino acid 296 of SEQ ID NOS: 1. Andexanet comprises two chains, designated SEQ ID NO: 3 (light chain) and SEQ ID NO: 4 (heavy chain).

[0035] FXa derivatives also encompass those that have undergone mutations, post-translational modifications, and / or protein alterations during production. For example, in another aspect, these FXa derivatives, whether or not they contain Ser379 modification, may contain modifications to His (changing to Ala) and / or Asp (changing to Ala / Asn) residues in the catalytic triad, as well as missing or modified Gla domains. These modifications provide FXa derivatives with reduced enzyme activity that do not compete with FXa for assembly into the prothrombinase complex.

[0036] In some embodiments, the heavy chain of the FXa derivative has one or two O-linked glycosylations. In some embodiments, the heavy chain may have a C-terminal truncation of one amino acid residue, or a C-terminal truncation of up to 13, 14, or 15 amino acid residues. In some embodiments, the light chain may have an N-terminal truncation.

[0037] This disclosure provides various bioequivalents of the disclosed FXa derivative sequences, or peptides having specific sequence identity with these FXa derivatives. In one aspect, such bioequivalents retain the structural features of these FXa derivatives, namely modified active sites or heavy chains and the absence or modification of Gla domains. In another aspect, such bioequivalents retain the functional features of these FXa derivatives, namely, they do not compete with FXa for assembly into the prothrombinase complex and possess reduced catalytic activity. Furthermore, such bioequivalents can bind to and / or substantially neutralize FXa inhibitors. Table 1. Peptide sequence of activated human factor X (FXa) (SEQ ID NO: 1) Table 2. Peptide sequence of Andexanet (SEQ ID NO: 2)

[0038] The term "factor Xa inhibitor" or "factor Xa inhibitor" refers to a compound that can directly or indirectly inhibit the activity of coagulation factor Xa in catalyzing the conversion of prothrombin to thrombin, in vitro and / or in vivo.

[0039] “Direct Factor Xa inhibitors” or “direct FXa inhibitors” bind directly to FXa. Non-limiting examples include apixaban, rivaroxaban, edoxaban, betrixaban, NAP 5, rNAPc2, tissue factor pathway inhibitors, DX-9065a (e.g., described in Herbert, JM, et al, J Pharmacol Exp Ther. 1996 276(3):1030-8), YM-60828 (e.g., described in Taniuchi, Y., et al, Thromb Haemost. 1998 79(3):543-8), YM-150 (e.g., described in Eriksson, BI et. al, Blood 2005;106(11), Abstract 1865), TAK 442, PD-348292 (e.g., described in Pipeline Insight: Antithrombotics - Reaching the Untreated Prophylaxis Market, 2007), omexaban, LY517717 (e.g., described in Agnelli, G., et al, J.Thromb. Haemost. 2007 5(4):746-53), GSK913893, razaxaban, or pharmaceutically acceptable salts thereof, and combinations thereof.

[0040] “Indirect factor Xa inhibitors” or “indirect FXa inhibitors” inhibit FXa activity through one or more other factors. Non-limiting examples of indirect factor Xa inhibitors include enoxaparin, fondaparinux, edraparinux, biotinylated edraparin, fragmin, tinzaparin, low molecular weight heparin (“LMWH”), and combinations thereof.

[0041] In one embodiment, the factor Xa inhibitor is selected from apixaban, rivaroxaban, edoxaban, betrixaban, enoxaparin, and combinations thereof. II. Improves hemostatic efficacy in patients with acute cerebral hemorrhage

[0042] Anticoagulants meet market demand for treating or preventing unwanted thrombosis in patients with a predisposition to thrombosis (e.g., those with coagulation disorders, those requiring prolonged bed rest, or those undergoing surgery). However, one of the major limitations of anticoagulation therapy is the risk of treatment-related bleeding and the limited ability to rapidly reverse anticoagulant activity in cases of overdose or the need for emergency surgery.

[0043] One embodiment of this disclosure provides a method for reducing anti-FXa activity and / or improving hemostatic efficiency in patients with acute intracranial hemorrhage (ICH).

[0044] Patients with acute ICH using factor Xa inhibitors (FXa) are at high risk of hematoma expansion and poor prognosis. Andexanet binds to FXa inhibitors and rapidly reverses anticoagulation. Patients with acute ICH using FXa inhibitors should be treated with andexanet or standard treatment as a control within 6 hours of symptom onset. Hemostatic efficacy requires hematoma expansion ≤35%, a change of <7 points on the National Institutes of Health Stroke Scale, and no rescue therapy used.

[0045] As shown in Example 1, a clinical trial enrolled 530 patients; 87% had atrial fibrillation. Most patients receiving standard treatment (86%) received prothrombin complex concentrate. Effective hemostasis was achieved in 63.9% of patients in the andexanet group and 52.4% of patients receiving standard treatment, an increase of 11.0 patients per 100 treated patients with andexanet (p=0.009). The median reduction in anti-FXa activity was 94.4% in the andexanet group and 23.5% in the standard treatment group (p<0.001). Thrombotic events occurred in 10.3% of patients receiving andexanet and 5.6% of patients receiving standard treatment, an increase of 4.6 patients per 100 treated patients with andexanet (p=0.048).

[0046] Therefore, clinical trial results indicate that andexanet can rapidly reduce anti-FXa activity in patients with acute ICH, reduce hematoma expansion, and improve hemostatic efficacy. In particular, when the anti-FXa inhibitor is a direct inhibitor such as apixaban and rivaroxaban, andexanet is significantly more effective in reducing its activity compared to conventional treatment (Example 2). Therefore, andexanet may be suitable for patients using FXa inhibitors who develop acute ICH.

[0047] It was also observed that higher hematoma enlargement (HE) was associated with a higher hematoma growth rate (a combined indicator of time from symptom onset to baseline scan and baseline hematoma volume) and higher diastolic blood pressure (Example 3). Patients predicted to have higher HE were more likely to benefit from andexanet treatment.

[0048] Therefore, according to one embodiment of this disclosure, a method is provided for evaluating hemostatic efficacy in a patient with intracranial hemorrhage during anticoagulation therapy with a factor Xa (FXa) inhibitor. In some embodiments, the method includes administering an FXa derivative of this disclosure to the patient, obtaining a blood sample from the patient after administration, and measuring the anti-FXa activity in the sample. The anti-FXa activity can be used to predict the hemostatic efficacy in the patient. In some embodiments, the FXa inhibitor is a direct FXa inhibitor. In some embodiments, the FXa inhibitor is apixaban. In some embodiments, the FXa inhibitor is rivaroxaban.

[0049] Intracranial hemorrhage (ICH) refers to bleeding within the skull or brain. It is a serious medical emergency because the accumulation of blood within the skull can increase intracranial pressure, potentially compressing vulnerable brain tissue or restricting its blood supply. A severe increase in intracranial pressure (ICP) can lead to brain herniation, where a portion of the brain is compressed through the skull structure. Intracranial hemorrhage occurs when a blood vessel within the skull ruptures or leaks. It can be caused by physical trauma or non-traumatic factors. Anticoagulation therapy and coagulation disorders can both increase the risk of intracranial hemorrhage.

[0050] In some embodiments, the patient has intracranial hemorrhage. In some embodiments, the patient has a subtype of intracranial hemorrhage, such as intraaxial hemorrhage (brain hemorrhage), extraaxial hemorrhage (including epidural hemorrhage, subdural hemorrhage, and subarachnoid hemorrhage), epidural hematoma, subdural hematoma, or subarachnoid hemorrhage.

[0051] Intraaxial hemorrhage is bleeding within the brain itself, also known as cerebral hemorrhage. This subtype includes intraparenchymal hemorrhage (bleeding within brain tissue) and intraventricular hemorrhage (bleeding within the ventricles, especially common in premature infants). Intraaxial hemorrhage is more dangerous and more difficult to treat than extraaxial hemorrhage.

[0052] "Extra-axial hemorrhage" refers to bleeding that occurs within the skull but outside the brain tissue. Examples of extra-axial hemorrhage include epidural hemorrhage, subdural hemorrhage, and subarachnoid hemorrhage.

[0053] Epidural hemorrhage (epidural hematoma) occurs between the dura mater (the outermost layer of meninges) and the skull, caused by trauma. It can be caused by a tear in an artery, most commonly the middle meningeal artery. This is a dangerous type of injury because the bleeding originates from a high-pressure system and can rapidly lead to a fatal increase in intracranial pressure. However, it is the least common type of meningeal hemorrhage, accounting for 1% to 3% of head injury cases.

[0054] Subdural hemorrhage is caused by a tear in a bridging vein in the subdural space (between the dura mater and the arachnoid mater).

[0055] Subarachnoid hemorrhage occurs between the arachnoid and pia mater layers. Like intraparenchymal hemorrhage, it can be caused by trauma, rupture of an aneurysm, or arteriovenous malformation. Blood can be seen flowing into the brain in layers along the sulci and fissures, or filling the subarachnoid cisterns (most commonly the optic chiasm cisternose, as the anterior cerebral artery and its branches of the Circle of Willis are located within this space). A typical presentation of subarachnoid hemorrhage is a sudden onset of severe headache (thunderbolt-like headache). This can be a dangerous condition requiring urgent neurosurgical evaluation and sometimes emergency intervention.

[0056] Epidural hematoma (EDH) is a rapidly accumulating hematoma between the dura mater and the skull. These patients have a history of head trauma with loss of consciousness, followed by a period of lucidity, and then loss of consciousness again. Clinically, it occurs within minutes to hours. Many of these injuries are associated with tears in the middle meningeal artery. On a head CT scan, the extracranial hematoma may appear as a "lenticular" or convex shape, not crossing the cranial sutures.

[0057] A subdural hematoma occurs when a bridging vein tears between the cerebral cortex and the draining venous sinuses. Sometimes it can be caused by a tear in an artery on the surface of the brain. Acute subdural hematomas are often associated with cortical injury and therefore have a less favorable prognosis than epidural hematomas. Clinical features depend on the location and severity of the injury. Patients may have a history of loss of consciousness, but this usually resolves and does not recur. Clinical presentation occurs within hours. A crescent-shaped hematoma compressing the brain and crossing cranial sutures will be visible on a head CT scan. If there is a significant pressure effect on the brain, craniotomy and surgical removal are necessary. Complications include focal neurological deficits depending on the location of the hematoma and brain injury, increased intracranial pressure leading to brain herniation, ischemia due to reduced blood supply, and seizures.

[0058] Subarachnoid hemorrhage (SAH) is bleeding that enters the subarachnoid space—the area between the arachnoid mater and the pia mater surrounding the brain. Aside from head injuries, it can occur spontaneously, usually caused by a ruptured cerebral aneurysm. Symptoms of SAH include rapid onset of severe headache (thunderbolt headache), vomiting, confusion or decreased level of consciousness, and sometimes seizures. Diagnosis is usually confirmed by a head CT scan or occasionally by a lumbar puncture. Treatment involves timely neurosurgical or radioguided intervention, using medications and other therapies to help prevent recurrence of the hemorrhage and complications.

[0059] The FXa derivative can be administered via intravenous bolus injection, a combination of bolus and infusion, or subcutaneous administration. In some embodiments, about 10% to about 20% of the formulation is administered as a bolus injection, with the remainder infused over the time before bleeding substantially stops. The infusion is expected to last for about 6 hours, or about 6 to about 12 hours, or about 12 to about 24 hours, or 48 hours.

[0060] In some embodiments, the FXa derivative is administered via intravenous (IV) bolus at a target rate of approximately 30 mg / min, followed by continuous infusion over 120 minutes. In some embodiments, the initial IV bolus contains approximately 300-500 mg of the FXa derivative. In some embodiments, the initial IV bolus contains approximately 350-450 mg of the FXa derivative. In some embodiments, the initial IV bolus contains approximately 380-420 mg of the FXa derivative. In some embodiments, the initial IV bolus contains approximately 400 mg of the FXa derivative.

[0061] In some embodiments, the initial IV bolus contains about 700-900 mg of the FXa derivative. In some embodiments, the initial IV bolus contains about 750-850 mg of the FXa derivative. In some embodiments, the initial IV bolus contains about 800 mg of the FXa derivative.

[0062] In some implementations, subsequent IV infusions are administered at approximately 4 mg / min over 120 minutes. In some implementations, subsequent IV infusions are administered at approximately 8 mg / min over 120 minutes.

[0063] One embodiment provides a method for improving hemostatic efficacy in a patient with intracranial hemorrhage during anticoagulation therapy with a factor Xa (FXa) inhibitor, comprising administering an FXa derivative to the patient, the FXa derivative being missing at least 50% of amino acid residues 6-39 of the light chain and having an active site on the heavy chain modified, wherein the FXa derivative has reduced catalytic activity compared to wild-type FXa protein and is capable of binding the factor Xa inhibitor.

[0064] In some implementations, the administration is performed within 6 hours of the onset of symptoms of intracranial hemorrhage, or preferably within 3 hours of the onset of symptoms of intracranial hemorrhage.

[0065] In some implementations, the administration is performed within 15 hours after the patient takes the FXa inhibitor.

[0066] In some embodiments, the administration includes a bolus injection of the FXa derivative.

[0067] In some embodiments, the bolus injection contains 300-500 mg of the FXa derivative, or preferably 350-450 mg of the FXa derivative.

[0068] In some embodiments, the administration further includes infusion of the FXa derivative following a bolus injection.

[0069] In some embodiments, the infusion comprises 400-560 mg of the FXa derivative, or preferably 450-510 mg of the FXa derivative.

[0070] In some embodiments, the dosage of the FXa derivative is determined according to the selection criteria in Table 1. A higher dosing regimen (e.g., an 800 mg bolus over 30 minutes, total infusion dose of 960 mg) may be used when the last FXa inhibitor dose was high (e.g., rivaroxaban >10 mg, apixaban >5 mg, edoxaban >30 mg, or enoxaparin >40 mg) and the FXa derivative was administered within 8 hours of the FXa inhibitor administration. A higher dosing regimen (e.g., an 800 mg bolus over 30 minutes, total infusion dose of 960 mg) may also be used if the FXa derivative was administered more than 15 hours after the FXa inhibitor administration, or if the timing of the FXa inhibitor administration is unknown.

[0071] In contrast, a lower dosing regimen can be used when the last FXa inhibitor dose is low (e.g., rivaroxaban ≤10 mg, apixaban ≤5 mg, edoxaban ≤30 mg, or enoxaparin ≤40 mg) and the FXa derivative is administered within 8 hours of the FXa inhibitor dose (e.g., a 400 mg bolus over 15 minutes, for a total infusion of 480 mg). This lower dosing regimen can also be used, for example, when the last FXa inhibitor dose is between 8 and 15 hours prior to the administration of the FXa derivative.

[0072] In some implementations, the patient is at least 75 years old.

[0073] In some implementations, the patient's baseline NIHSS (NIH Stroke Scale / Score) is greater than 9.

[0074] In one implementation, a method for selecting patients to receive treatment with factor Xa (FXa) derivatives is also provided. As shown in Example 3, a higher pre-scan hematoma growth rate (a combined indicator of the time from symptom onset to baseline scan and baseline hematoma volume) and higher diastolic blood pressure can predict hematoma expansion in FXa-related ICH patients, but not thrombotic events. Figure 7 In summary, patients with a pre-scan hematoma growth rate ≥11 mL / hour had the highest risk of hematoma expansion; patients with a pre-scan hematoma growth rate of 1 to <11 mL / hour had the moderate risk of hematoma expansion; and patients with a pre-scan hematoma growth rate <1 mL / hour had the lowest risk of hematoma expansion. Regarding diastolic blood pressure, data showed that higher diastolic blood pressure (e.g., >95 mm Hg) was associated with a higher risk of hematoma expansion.

[0075] Therefore, in one embodiment, this disclosure provides a method for selecting a patient to receive treatment with a factor Xa (FXa) derivative, comprising (a) measuring a baseline hematoma volume after the onset of intracranial hemorrhage symptoms in a patient receiving anticoagulation therapy with a factor Xa inhibitor, thereby obtaining a hematoma growth rate, which is the baseline hematoma volume divided by the time period from the onset of symptoms to the measurement; and (b) selecting the patient to receive FXa derivative treatment when the hematoma growth rate is greater than 1 mL / hour.

[0076] As used herein, “hematoma growth rate” refers to the initial hematoma growth rate from the onset of ICH symptoms to the time of baseline imaging (and therefore “pre-scan” hematoma growth rate) or administration of an FXa derivative. It can be calculated by dividing the measured baseline hematoma volume by the time. In some embodiments, the baseline imaging or administration of the FXa derivative is performed within 24 hours of the onset of ICH symptoms. In some embodiments, the baseline imaging or administration of the FXa derivative is performed within 20, 18, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 hour of the onset of ICH symptoms. In some embodiments, the baseline imaging or administration of the FXa derivative is performed within 6 hours of the onset of ICH symptoms. In some embodiments, the baseline imaging or administration of the FXa derivative is performed between 2 and 4 hours of the onset of ICH symptoms.

[0077] In some embodiments, patients selected to receive FXa derivative treatment have a hematoma growth rate greater than or equal to 11 mL / hour. In some embodiments, patients selected to receive FXa derivative treatment have a hematoma growth rate greater than or equal to 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 mL / hour.

[0078] In some embodiments, patients selected to receive FXa derivative therapy have a diastolic blood pressure greater than 95 mm Hg. In some embodiments, patients selected to receive FXa derivative therapy have a diastolic blood pressure greater than 80, 85, 90, 95, 100, 105, 110, 115, or 120 mm Hg.

[0079] Another embodiment provides a method for improving hemostatic efficacy in a patient with intracranial hemorrhage during anticoagulation therapy with a factor Xa (FXa) inhibitor, comprising administering an FXa derivative to the patient, the FXa derivative being lacking at least 50% of amino acid residues 6-39 of its light chain and having its active site on the heavy chain modified, wherein the FXa derivative exhibits reduced catalytic activity compared to wild-type FXa protein and is capable of binding the factor Xa inhibitor. In some embodiments, the patient has a hematoma growth rate greater than 1 mL / hour after the onset of symptoms of intracranial hemorrhage. In some embodiments, the patient has a hematoma growth rate greater than or equal to 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 mL / hour. In some embodiments, the patient has a diastolic blood pressure greater than 80, 85, 90, 95, 100, 105, 110, 115, or 120 mm Hg.

[0080] In some embodiments, the FXa derivative is a double-chain protein comprising a light chain containing the amino acid sequence of SEQ ID NO:3 or a first peptide having at least 85% sequence identity with SEQ ID NO:3, and a heavy chain containing the amino acid sequence of SEQ ID NO:4 or a second peptide having at least 85% sequence identity with SEQ ID NO:4. In some embodiments, the Xa factor derivative is andexanet alfa. III. Xa factor derivative compositions

[0081] In various embodiments, the factor Xa derivative is administered to the patient. Therefore, compositions comprising the factor Xa derivative are also provided. In some embodiments, the composition further comprises a pharmaceutically acceptable carrier. In some embodiments, the factor Xa derivative is conjugated with a portion capable of prolonging the circulating half-life of the derivative.

[0082] "Pharmaceutically acceptable carrier" means any diluent, excipient, or carrier that can be used in the compositions disclosed herein. Pharmaceutically acceptable carriers include saline, ion exchangers, alumina, aluminum stearate, lecithin, serum proteins such as human serum albumin, buffering substances such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, salts or electrolytes such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinylpyrrolidone, cellulose, polyethylene glycol, sodium carboxymethyl cellulose, polyacrylates, waxes, polyethylene polyoxypropylene block polymers, polyethylene glycol, and lanolin. Suitable pharmaceutical carriers are described in Remington's Pharmaceutical Sciences, Mack Publishing Company, which is the standard reference textbook in the field. They are preferably selected based on the intended form of administration (i.e., oral tablets, capsules, elixirs, syrups, etc.) and in accordance with standard pharmaceutical practice.

[0083] The formulations disclosed herein can be manufactured by methods well known in the art, such as conventional granulation, mixing, dissolving, encapsulation, lyophilization, or emulsification. The compositions can be produced in various forms, including granules, precipitates or microparticles, powders (including lyophilized, rotary-dried, or spray-dried powders), amorphous powders, injections, emulsions, elixirs, suspensions, or solutions. The formulations may optionally contain stabilizers, pH adjusters, surfactants, bioavailability modifiers, and combinations thereof.

[0084] In one embodiment, the FXa derivative is lyophilized. Methods for lyophilizing peptides are well known in the art. In some embodiments, the FXa derivative is provided in single-use vials containing 100, 200, or 400 mg of lyophilized FXa derivative, formulated with the inactive ingredient tromethamine (Tris), L-arginine hydrochloride, sucrose (2% w / v), mannitol (5% w / v), and polysorbate 80 (0.01% w / v) at pH 7.8. It can be reconstituted with sterile water for injection for intravenous (IV) administration.

[0085] Pharmaceutical formulations can also be prepared as liquid suspensions or solutions using sterile liquids (e.g., oils, water, alcohols, and combinations thereof). Pharmaceutically suitable surfactants, suspending agents, or emulsifiers may be added for oral or parenteral administration. Suspensions may include oils such as peanut oil, sesame oil, cottonseed oil, corn oil, and olive oil. Suspension preparations may also contain fatty acid esters such as ethyl oleate, isopropyl myristate, fatty acid glycerides, and acetylated fatty acid glycerides. Suspension formulations may include alcohols such as ethanol, isopropanol, cetyl alcohol, glycerol, and propylene glycol. Ethers such as polyethylene glycol, petroleum hydrocarbons such as mineral oil and petrolatum, and water may also be used in suspension formulations.

[0086] The formulations are intended for administration to mammals, preferably humans. These formulations of the present disclosure can be administered in various ways, preferably parenterally.

[0087] As used herein, the term "parenteral" includes subcutaneous, intravenous, intramuscular, intra-articular, intrasynovial, intrasternal, intrathecal, intrahepatic, intralesional, and intracranial injection or infusion techniques. However, in cases where the neutralized FXa inhibitor has a long plasma half-life, continuous infusion or sustained-release formulations may be required to bind the FXa inhibitor, thereby releasing active FXa before the FXa inhibitor is cleared from the body. Therefore, in one aspect, the formulation is administered to the subject via bolus injection. In another aspect, the formulation is administered via infusion. In yet another aspect, the formulation is administered via a combination of bolus and infusion.

[0088] The sterile injectable forms of the compositions disclosed herein may be aqueous or oily suspensions. These suspensions can be formulated using suitable dispersants or wetting agents and suspending agents according to techniques known in the art. Sterile injectable formulations may also be sterile injectable solutions or suspensions in non-toxic, parenteral-acceptable diluents or solvents, such as solutions in 1,3-butanediol. Acceptable carriers and solvents that can be used include water, Ringer's solution, and isotonic sodium chloride solution. Furthermore, sterile, non-volatile oils are commonly used as solvents or suspension media. For this purpose, any mild, non-volatile oil can be used, including synthetic monoglycerides or diglycerides. Fatty acids such as oleic acid and its glyceride derivatives can be used to prepare injectable formulations, as can natural pharmaceutically acceptable oils such as olive oil or castor oil, especially their polyoxyethylated versions. These oil solutions or suspensions may also contain long-chain alcohol diluents or dispersants, such as carboxymethyl cellulose or similar dispersants commonly used in the preparation of pharmaceutically acceptable dosage forms, including emulsions and suspensions. Other commonly used surfactants, such as Tween, Span, and other emulsifiers or bioavailability enhancers commonly used in the preparation of pharmaceutically acceptable solid, liquid, or other dosage forms, may also be used for formulation purposes. The composition can be formulated for parenteral administration by injection, such as bolus injection or continuous infusion. Injectable unit dosage forms may be in ampoules or multi-dose containers.

[0089] In addition to the dosage forms described above, pharmaceutically acceptable excipients and carriers, as well as dosage forms, are generally known to those skilled in the art and are included in this disclosure. It should be understood that the specific dosage and treatment regimen for any particular patient will depend on a variety of factors, including the activity of the specific FXa derivative used, the patient's age, weight, general health condition, sex and diet, liver and kidney function, as well as the timing of administration, excretion rate, drug combination, the judgment of the attending physician or veterinarian, and the severity of the specific disease being treated. Example

[0090] This disclosure is further understood through the following examples, which are intended purely as examples of this disclosure. The scope of this disclosure is not limited to the exemplary embodiments, which are intended to illustrate only one aspect of this disclosure. Any functionally equivalent methods are within the scope of this disclosure. Various modifications to this disclosure, in addition to those described herein, will become apparent to those skilled in the art from the foregoing description and drawings. These modifications fall within the scope of the appended claims. Example 1. Andexanet for acute intracerebral hemorrhage associated with factor Xa inhibitors

[0091] This embodiment tested the ability of andexanet alfa (or andexanet for short) to reduce anti-factor Xa (FXa) activity and restore hemostatic efficacy in patients with acute massive bleeding associated with anticoagulation therapy based on factor Xa inhibitors.

[0092] “Standard treatment” was used as a control. Standard treatment included any treatment other than andexanet administered within 3 hours of randomization (including no treatment), which the investigators considered appropriate. method Experimental Design and Supervision

[0093] The protocol was approved by an independent ethics committee at each research center. Consent was obtained directly, through an agent, or delayed upon approval. The trial was conducted in accordance with ethical principles derived from the Declaration of Helsinki and the International Ethical Guidelines of the Council of Medical Sciences. An independent Data Safety Monitoring Board (DSMB) oversaw the trial.

[0094] This study was designed and coordinated by the Population Health Research Institute (PHRI) (a joint institute of McMaster University and Hamilton Health Sciences) and funded by AstraZeneca Rare Diseases Alexon. The study protocol was modified during the study. Although treatment at the study site was not blinded, the steering committee members consistently blinded the aggregated statistics and trial results. patient

[0095] Initially, any patient with acute FXa-related intracranial hemorrhage was eligible for inclusion. However, after protocol revision, only patients with acute ICH as the primary bleeding event and an estimated hematoma volume ≥0.5 to ≤60 mL were eligible; and the time from the onset of bleeding symptoms to baseline imaging scans must be ≤6 hours. Intracranial hemorrhage must be radiographically observable within ≤2 hours prior to randomization. Patients receiving FXa inhibitor therapy were eligible for inclusion, with the last dose ≤15 hours prior to randomization. Patients with any of the following conditions were excluded: Glasgow Coma Scale score <7 at consent, National Institutes of Health Stroke Scale (NIHSS) >35, planned surgery within 12 hours, or a recent history of thrombotic events. Randomization and treatment

[0096] Patients were randomly assigned 1:1 to the andexanet group or the standard treatment group. Stratification factors (after Amendment 1) included: intention to use prothrombin complex concentrate (PCC) if randomized to the standard treatment group, and the time from symptom onset to baseline imaging scan (<180 minutes vs. ≥180 minutes). The randomization protocol was generated by PHRI. Before the database was locked and unblinded, 20 patients were found to have not given proper consent; their data have been removed from the database.

[0097] Patients assigned to the andexanet group received either a high-dose or low-dose bolus over 15–30 minutes, followed by continuous infusion over 2 hours. The high-dose regimen consisted of an 800 mg bolus over 30 minutes, for a total infusion of 960 mg. The low-dose regimen consisted of a 400 mg bolus over 15 minutes, for a total infusion of 480 mg.

[0098] Dosage is based on the FXa inhibitor used and the amount and time of the last administration (Table 1). Routine treatment is determined at the discretion of the local physician, but excluding andexanet, PCC may be included. Table 1: Andexanet Dosage Selection Endpoint and Assessment

[0099] The primary efficacy endpoint was effective hemostasis assessed 12 hours after randomization. Excellent or good hemostasis was defined as a change in hematoma volume ≤20% (excellent) or ≤35% (good) between baseline and 12 hours, an increase in NIHSS score <7 between baseline and 12 hours, and no rescue treatment (e.g., andexanet, PCC, or decompression hematoma surgery) received within 3 to 12 hours after randomization. The 12-hour NIHSS assessment was performed by trained, blinded healthcare professionals. Secondary efficacy endpoints were the percentage change in anti-FXa activity from baseline to its lowest point within the first 2 hours after randomization. The modified Rankin Scale (mRS) at 30 days post-randomization was an exploratory outcome. Safety endpoints were assessed at 30 days, including thromboembolic events and death. A blinded endpoint determination committee reviewed all potential thrombotic events and assessments of hemostatic efficacy. In cases where brain scans or NIHSS assessments were unavailable, the committee assessed whether the lack was due to clinical reasons (e.g., patient death) or administrative reasons. A blinded core laboratory reviews brain images to determine changes in hematoma volume. Statistical analysis

[0100] Based on the assumption that the hemostatic efficacy rates for patients treated with standard therapy and andexanet were 70% and 80%, respectively, a total sample size of 900 patients was estimated to be needed to detect an absolute difference in effective hemostasis rate with 90% power at a two-sided Type I error rate of 5%. The primary efficacy analysis used the Cochran-Mantel-Haenszel test, stratified by time from symptom onset to baseline imaging (<180 minutes vs. ≥180 minutes), to compare the proportion of patients with effective hemostasis between the andexanet and standard therapy groups. Secondary endpoints, such as the percentage change in anti-FXa activity, were assessed using ordinal data-based analysis of covariance (ANCOVA), with intention to receive standard therapy, time from symptom onset to baseline imaging, and baseline anti-FXa activity as covariates. Both efficacy and safety analyses were based on intention-to-treat analyses.

[0101] Two effective hemostasis analyses are planned, at 50% and 100% of planned patients having completed the assessment. A stratified test procedure controls for a population type I error rate of 5%, with a significance level of 0.0310 at the first analysis. Interim analyses are performed by unblinded statisticians at PHRI and reviewed by the DSMB, which recommends whether to discontinue the trial. result

[0102] The study enrolled 530 patients at 131 centers in 23 countries. The interim analysis of efficacy met the pre-specified early trial cessation criteria, and the DSMB recommended cessation of the trial. Between the database lockout point of the interim analysis and the DSMB cessation recommendation point, an additional 78 patients were enrolled, bringing the total to 530. Of the patients randomized to standard treatment, 230 (86.1%) received PCC within the first 3 hours after randomization (median dose 3000 IU (Q1, Q3 2000, 3500 IU)). The type of PCC used in 137 patients is known (128 (93%) used factor 4 PCC, 4 patients (3%) used factor 3 PCC, and 5 patients (4%) used activated PCC or factor 8 bypass activator (FEIBA)). For andexanet patients, 199 (75.7%) received the low-dose regimen, and the remainder received the high-dose regimen. Eighteen patients could not be assessed for hemostatic efficacy due to a lack of necessary data (e.g., follow-up brain scans or NIHSS). Ten of these were determined to be due to management reasons (no clinical cause for the lack of data was found) (7 in the andexanet group); eight were due to clinical deterioration (e.g., death) (5 in the andexanet group). Five patients randomized to andexanet did not receive andexanet (two received PCC); four patients randomized to standard care received andexanet.

[0103] The enrolled patients were older and had a heavy vascular disease burden, including 21.3% with a history of stroke, 12.3% with a history of myocardial infarction, 8.5% with a history of pulmonary embolism, and 8.9% with a history of venous thrombosis (Table 2). Most patients (87.4%) had a history of atrial fibrillation. Apixaban was the most commonly used FXa inhibitor (60.4%). The bleeding site was intracerebral in 91.9% of patients. 12.3% of patients had a history of trauma prior to bleeding. The median hematoma volume at presentation was 9.8 ml (Q1, Q3 3.7, 24.2), and the median baseline NIHSS was 9.0 (Q1, Q3 5.0, 16.0). The median time from symptom onset to baseline scan was 2.3 hours (Q1, Q3 1.4, 3.8), the median time from scan to randomization was 1.1 hours (Q1, Q3 0.7, 1.6), and the median time from randomization to andexanet treatment was 0.3 hours (Q1, Q3 0.2, 0.5). Table 2. Baseline Characteristics therapeutic effect

[0104] In the andexanet group, 168 patients (63.9%) were rated as having excellent or good hemostasis, compared to 140 patients (52.4%) in the standard treatment group, representing an increase of 11.0 patients per 100 treated patients in the andexanet group (95% CI 2.8, 19.3) (p=0.009) (Table 3). The additional patients with excellent / good hemostasis in the andexanet group almost entirely fell into the excellent category (hematoma expansion ≤20%). After excluding 10 patients whose hemostasis could not be assessed for management reasons, the number of patients with excellent / good hemostasis per 100 treated patients in the andexanet group increased by 12.3 (95% CI 4.0, 20.5). Based on a hematoma volume change of ≤35%, the number of patients with excellent / good hemostasis per 100 treated patients in the andexanet group increased by 13.1 (95% CI 5.2, 21.0). Very large hematoma expansion (≥12.5 ml) or death within 12 hours occurred in 29 patients (11.6%) in the andexanet group and 48 patients (19.0%) in the standard treatment group, a reduction of 7.4 patients per 100 treated patients (95% CI 1.2, 13.6). The proportion of patients with a modified Rankin score ≤3 at 30 days was similar in both groups (69 / 246 (28.0%) in the andexanet group and 79 / 255 (31.0%) in the standard treatment group). The median change in FXa activity from baseline to the lowest point at 1 or 2 hours was 94.4% in the andexanet group and 23.5% in the standard treatment group (p<0.001). Figure 1 ). Table 3: Therapeutic Outcomes Thrombotic events and death within 30 days

[0105] In the intention-to-treat analysis, thrombotic events occurred in 27 patients (10.3%) in the andexanet group and 15 patients (5.6%) in the standard treatment group, an increase of 4.6 events per 100 patients treated with andexanet (95% CI 0.1, 9.2; p=0.048) (Table 4). Thrombotic events in the safety population (patients were assigned to treatment groups based on the actual treatment received) are listed in Table 5. Ischemic stroke occurred in 17 patients (6.5%) in the andexanet group and 4 patients (1.5%) in the standard treatment group, an increase of 5.0 events per 100 patients treated with andexanet (95% CI 1.5, 8.8). There was no difference in mortality, occurring in 73 patients (27.8%) receiving andexanet and 68 patients (25.5%) receiving standard treatment. Table 4. Thrombotic events and deaths within 30 days Table 5: Thrombotic events and deaths within 30 days (safety set*) Subgroup analysis

[0106] Figure 2 Forest plots showing selected subgroups of hemostatic efficacy outcomes. No significant treatment interactions were observed, indicating that improvements in hemostatic efficacy were consistent across subgroups. Baseline hemostatic efficacy in the standard treatment group varied depending on clinical presentation. Patients with a symptom onset to randomization time <2 hours and NIHSS ≥9 had a better or better hemostatic efficacy rate of less than 50% with standard treatment, while the increase in better or better hemostatic efficacy with andexanet was above average. Figure 3 Forest plots of selected subgroups of thrombotic event outcomes are shown. Interaction p-values ​​were not calculated due to the small number of events. Patients with a history of stroke or myocardial infarction (known as a high-risk group for stroke with atrial fibrillation) may have a higher than average risk of thrombotic events when using andexanet.

[0107] This embodiment demonstrates that andexanet increased the number of patients with hemostatic efficacy in patients who developed acute ICH while receiving FXa inhibitor therapy compared to standard treatment. This measure combined radiographic assessment of hematoma expansion, clinical assessment using the NIHSS, and the absence of rescue therapy. Hematoma expansion is the most important modifiable risk factor for patients with acute ICH and is known to have a significant impact on morbidity and mortality. For example, in the INTERACT1 trial data (8), each 1 mL of hematoma growth was associated with a 5% (95% CI 2%–9%) increase in the chance of death or dependence at 90 days. Hematoma expansion ≥12.5 ml was also highly associated with poor clinical outcomes in ICH patients, with a positive predictive value of 80% for severe disability or death (8). Therefore, andexanet increased the number of patients with hematoma enlargement ≤35% by 13.1 per 100 patients (95% CI 5.2, 21.0) and improved overall hemostatic efficacy by 11.0% (95% CI 2.8, 19.3), which were significant and clinically relevant. Absolute hematoma enlargement (≥12.5 mL) was also significantly reduced.

[0108] Andexanet significantly and rapidly reduces anti-FXa activity, while conventional treatment only provides a slight reduction. The efficacy of andexanet demonstrated in this study is consistent with its mechanism of action: rapidly isolating FXa inhibitor molecules to normalize natural hemostasis.

[0109] In summary, andexanet rapidly reduces anti-FXa activity in patients with acute ICH, decreases hematoma expansion, and improves hemostasis. Andexanet increases the risk of thrombotic events, including ischemic stroke. Andexanet should be considered for patients using FXa inhibitors who develop acute ICH. Example 2. Secondary endpoints of therapeutic effect

[0110] This embodiment describes the results of a clinical study extended from the trial reported in Example 1. The primary endpoint (i.e., effective hemostasis) of the extended study was similar to that of Example 1. In this embodiment, results of secondary endpoints are provided.

[0111] Overall, in patients receiving direct oral FXa inhibitors for acute ICH, andexanet was superior to conventional treatment in reducing anti-FXa activity at its lowest point from baseline to within 2 hours after randomization (Table 6, median reduction of -94.4% in the andexanet group and -27.5% in the conventional treatment group, p < 0.0001). Table 6. Summary of anti-FXa activity (ng / mL) by visit and treatment and prior FXa inhibitor group (ITT set, primary efficacy population)

[0112] The overall decrease in anti-FXa activity of FXa inhibitors was shown in Figure 4 The study showed a decrease in anti-FXa activity of each directly orally administered FXa inhibitor after treatment. Figure 5A -C

[0113] The correlation between anti-FXa activity and hemostatic efficacy was also determined. As shown in Table 7, there was a correlation between hemostatic efficacy and the percentage change in anti-FXa activity (odds ratio 0.9988, 95% CI [0.9952, 1.0024], AUC 0.56, 95% CI [0.51, 0.62]). Table 7. Correlation analysis between effective hemostasis and anti-FXa activity (ITT set, primary treatment population)

[0114] As shown in Examples 1 and 2, the primary efficacy target of the clinical study has been achieved. In patients receiving direct oral FXa inhibitors, andexanet was superior to conventional treatment in achieving effective hemostasis 12 hours after randomization for acute ICH (67.0% of patients in the andexanet group vs. 53.1% in the conventional treatment group, a difference of 13.4%, 95% CI [4.6%, 22.2%], p = 0.0032).

[0115] The primary endpoint results were consistent across predefined subgroups based on demographic and key baseline characteristics.

[0116] Secondary efficacy targets were also achieved. In patients receiving direct oral FXa inhibitors, andexanet was superior to conventional treatment in reducing antiFXa activity at its lowest point from baseline to within 2 hours after randomization for acute ICH.

[0117] A relationship was found between hemostatic efficacy and changes in the percentage of anti-FXa activity. The results of sensitivity analyses (including analyses of expanded populations) were consistent with those of the primary efficacy analysis. Example 3. Predictors of hematoma expansion in patients with cerebral hemorrhage and their response to Andexanet Alfa

[0118] This embodiment describes secondary analyses derived from the clinical trials reported in Examples 1 and 2. These secondary analyses support treatment approaches designed to identify FXa inhibitor-associated intracerebral hemorrhage (ICH) patients with a higher risk of hematoma expansion (HE) and who are more likely to benefit from andexanet treatment.

[0119] Treatment with factor Xa (FXa) inhibitors is associated with a high risk of hematoma expansion in patients with ICH. Final hematoma volume is a major determinant of the severity of primary and secondary injury following ICH. Therefore, hematoma expansion is considered a significant predictor of poor prognosis in patients with acute ICH. It is estimated that for every 1 mL and 10% increase in baseline hematoma volume, the likelihood of a patient moving one point towards more severe disability or death on the modified Rankin Scale (mRS) at 90 days increases by 6% and 16%, respectively. Therefore, reducing hematoma growth is an important mechanistic goal for improving clinical outcomes in treatment trials for patients with acute ICH.

[0120] Andexanet rapidly reverses the anticoagulant effects of FXa inhibitors and improves hemostatic efficacy. However, this benefit may be partially offset by an increase in thrombotic events in patients receiving andexanet, highlighting the importance of patient selection for optimal treatment outcomes. method: Research participants

[0121] Eligible ICH patients (excluding those with subdural, epidural, or subarachnoid hemorrhage) who were included in the trial and had interpretable baseline and subsequent 12-hour brain imaging were eligible for these secondary analyses. This study followed the Uniform Standard Reporting Guidelines for Trials. Baseline characteristics

[0122] Baseline demographics, medical history, medication use, stroke severity, and hematoma characteristics were collected at study enrollment. Pre-scan hematoma growth rate (mL / hour) was calculated as baseline hematoma volume divided by the time from symptom onset to baseline scan. ending

[0123] For this analysis, hematoma enlargement was defined as an increase in hematoma volume of ≥12.5 mL or ≥35% between baseline and brain imaging obtained 12 hours after randomization. These thresholds were chosen because they were strongly correlated with adverse outcomes in patients with acute ICH at 90 days of modified Rankin Scale (mRS) scores. The safety outcome was thrombotic events within 30 days. A blinded endpoint determination committee reviewed all potential thrombotic events. Hematoma volume analysis was performed in a dedicated imaging core laboratory by trained, blinded physicians using Quantomo software (Cybertrials, Inc., Calgary, Canada) to determine changes in hematoma volume. Statistical analysis

[0124] Baseline characteristics were summarized and compared between two groups defined by participants with and without hematoma expansion. Continuous variables were summarized as mean ± SD or median (interquartile range [IQR]) and compared between groups using the mean t-test or the median Wilcoxon rank-sum test. Categorical variables were reported as counts (percentages) and compared between groups using the Pearson chi-square test. Missing values ​​for time from symptom onset to treatment were imputed using the median of that variable in the corresponding treatment group.

[0125] Multivariate logistic regression was performed using dilated hematoma expansion as the outcome, and risk factors identified from baseline univariate analysis (p < 0.10) and the treatment group as independent variables. Odds ratios (OR) and 95% confidence intervals (CI) obtained from logistic regression were used to assess the association between risk factors and hematoma expansion. Because the indication for high-dose andexanet was highly correlated with baseline anti-FXa levels, only baseline anti-FXa levels, rather than the indication for high-dose andexanet, were included in the model to avoid collinearity. Furthermore, anti-FXa levels had a stronger biologically plausible causal relationship with hematoma expansion. Additionally, to avoid collinearity between pre-scan hematoma growth rate (mL / hour) and baseline ICH volume (mL) or time from symptom onset to treatment (hours), these variables were considered in two separate regression models. The final model was then applied to the safety outcome of thrombotic events within 30 days.

[0126] For the continuous variables identified in the above regression model that are significantly associated with hematoma expansion, the Wald confidence limit method was used to estimate the difference in the proportion of participants whose hematoma expansion occurred within the quartiles of these variables between the andexanet group and the conventional treatment group, and their 95% confidence intervals.

[0127] By fitting each corresponding logistic regression model (which contains two independent variables: a treatment variable and a study variable), the predicted probability of hematoma enlargement by treatment group is estimated at different levels for each independent variable.

[0128] The p-values ​​are two-tailed. Statistical significance is accepted at the 0.05 level. Statistical analysis was performed using SAS software (version 9.4). result:

[0129] Of the 530 patients enrolled between 2019 and 2023, 459 had baseline ICH or IVH and had adequate baseline and follow-up imaging, and were included in these analyses. The mean (± standard deviation, SD) age was 79.1 (±8.3) years, and 46.2% (n=212) were female. Most patients (99.1%) had intraparenchymal hemorrhage, with only 4 having primary intraventricular hemorrhage (0.9%), and 30 (6.5%) had a history of trauma prior to ICH. The median baseline hematoma volume (interquartile range, IQR) was 9.2 (3.5, 22.4) mL, and the NIHSS score was 9.0 (IQR 5.0, 16.0). The median time from symptom onset to baseline scan (IQR) was 2.3 hours (IQR 1.4, 3.8), and the median time from symptom onset to treatment was 4.0 hours (IQR 3.2, 5.5). The majority of patients assigned to the standard treatment group (86.4%) received PCC.

[0130] In univariate analysis, higher baseline NIHSS score, anti-FXa level, hematoma volume, and pre-scan hematoma growth rate were associated with hematoma enlargement (Table 8). Patients with hematoma enlargement also had higher baseline diastolic blood pressure, shorter time from symptom onset to treatment, and were more likely to be eligible for high-dose andexanet. Table 8. Baseline characteristics of stratification based on the presence or absence of hematoma expansion (≥12.5 ml or ≥35%) at 12 hours.

[0131] In the first multivariate regression model (Table 9, Model 1), shorter time from symptom onset to treatment (OR 0.73 per 1-hour increase, 95% CI 0.63–0.85, p<0.001), larger baseline hematoma volume (OR 1.11 per 10 mL, 95% CI 1.01–1.23, p=0.04), and higher diastolic blood pressure (OR 1.15 per 10 mm Hg (1.02–1.29, p=0.02)) were independently associated with hematoma expansion. In the second model, pre-scan hematoma growth rate (OR 1.03 per mL / hour, 95% CI 1.01–1.04, p<0.001) and diastolic blood pressure (OR 1.18 per 10 mm Hg, 95% CI 1.05–1.33, p<0.01) were associated with hematoma expansion. Table 9. Multivariate model of risk of hematoma expansion (≥12.5 ml or ≥35%) at 12 hours

[0132] Andexanet alfa showed consistent efficacy against hematoma expansion compared to conventional treatment across hematoma volume, treatment duration, and hematoma growth rate. Figure 6A -E).

[0133] The hematoma expansion rate in the standard treatment group increased from 27.9% of participants in the first quartile (≤3.5 mL) of baseline ICH volume to 53.6% of those in the fourth quartile (>22.4 mL). The corresponding hematoma expansion rates between the lowest and highest quartiles of time from symptom onset to treatment were 48.8% (≤3.3 hours) and 24.6% (>5.4 hours), respectively; the pre-scan hematoma growth rates were 20.0% (≤1.2 mL / hour) and 59.3% (>11.4 mL / hour), respectively; and the baseline diastolic blood pressure were 29.5% (≤73.0 mm Hg) and 51.8% (>95.0 mm Hg), respectively (Table 10). In this total participant sample, the number of participants requiring treatment (NNT) to prevent hematoma expansion using andexanet was 7. In patients at the highest risk quartile for baseline hematoma volume (>22.4 mL), time from symptom onset to treatment (≤3.3 hours), pre-scan hematoma growth rate (>11.4 mL / hour), and diastolic blood pressure (>95 mmHg), the NNTs were 4, 7, 4, and 6, respectively (Table 10). Baseline hematoma volume, time from symptom onset to treatment, diastolic blood pressure, or pre-scan hematoma growth rate did not predict thrombotic events (Table 11). In this ICH patient sample, the number of people requiring injury (NNH) resulting from additional thrombotic events was approximately 26 compared to standard treatment (an increase of 3.9 per 100 treated patients with andexanet [95% confidence interval -1.2, 8.9]). Table 10. Rate of hematoma expansion (≥12.5 ml or ≥35%) at 12 hours based on independent predictors of hematoma expansion and treatment group stratification. Table 11. Multivariate model of thrombotic event risk within 30 days

[0134] This embodiment demonstrates that three main factors independently predict the risk of hematoma expansion. These factors are: higher baseline hematoma volume, shorter duration from symptom onset to treatment (or scan), and higher baseline diastolic blood pressure. Two of these factors (volume and time) can be combined to form the pre-scan hematoma growth rate. Studies have also shown that andexanet has a highly consistent therapeutic effect in preventing hematoma expansion, with similar relative treatment effects observed in patients predicted to have a low or high risk of hematoma expansion. Since the restoration of normal coagulation function is urgently needed in patients with FXa inhibitor-associated acute ICH, these variables can be used to rapidly assess the benefit-risk ratio. Figure 7 ).

[0135] exist Figure 7In the table, the second and third quartiles of pre-scan hematoma growth rate from Table 10 were combined into the middle category. Compared with standard treatment, the absolute risk of thrombotic events with andexanet treatment was higher in patients with a history of ischemic stroke or myocardial infarction (10.1% in the andexanet group vs. 8.1% in the standard treatment group; adjusted difference per 100 treated patients [2.0, 95% confidence interval -4.3, 8.3; NNH: 50]), compared to 10.8% in patients without such a history (2.7% vs. 10.8%; adjusted difference per 100 treated patients 8.1, 95% confidence interval -0.3, 16.5; NNH: 12). The total number of thrombotic events was small, making further stratification of NNH by pre-scan hematoma growth rate impossible, but no association was observed between pre-scan hematoma growth rate and the risk of thrombotic events. Elevated blood pressure also increases the risk of hematoma enlargement, which should be considered in individualized treatment decisions.

[0136] The absolute risk reduction (ARR) and the corresponding NNT were robust across all quartiles of these variables (NNT mainly <10), with the largest ARR observed in patients at the highest quartiles of baseline hematoma volume (>22.4 mL) and pre-scan hematoma growth rate (>11.4 mL / h), where the NNT for preventing hematoma expansion was 4.

[0137] These data suggest that patient selection can optimize the benefit-risk ratio of andexanet treatment. In patients with baseline hematoma volume and diastolic blood pressure in the highest quartile and time from symptom onset to treatment in the lowest quartile, the hematoma expansion rate with conventional treatment was approximately 50%. The highest hematoma expansion rate, approaching 60% (59.3%), was observed in patients with pre-scan hematoma growth rate in the highest quartile. Notably, even in patients with these variables in the lowest risk quartile, the hematoma expansion rate with conventional treatment remained clinically significant (ranging from 20-30%), and the NNT for reducing hematoma expansion was robust (less than 10), and none of these variables were associated with thrombotic events. Therefore, by selecting patients at higher risk of hematoma expansion using these variables (particularly hematoma growth rate), the therapeutic effect of andexanet on hematoma expansion can be maximized while maintaining the same level of thrombotic event risk.

[0138] Based on these analyses, a simple model using hematoma growth rate, diastolic blood pressure, and a history of arterial thrombotic events can be used for individualized treatment decisions to select patients with the best risk-benefit ratio. Figure 7In balancing NNT (reducing hematoma expansion) and NNH (reducing thrombotic events), the estimated values ​​support that andexanet is superior to conventional treatment for FXa inhibitor-associated ICH patients who meet the trial inclusion criteria but have a history of arterial thrombotic events and exhibit low to moderate hematoma growth rates (<11 mL / h). Figure 7 Except for patients with )

[0139] These findings highlight the importance of blood pressure as a predictor of hematoma expansion in FXa inhibitor-associated ICH and further support the importance of adopting bundled care strategies in patients with acute ICH that prioritize timely restoration of normal coagulation and reduction of blood pressure, as well as other acute interventions.

[0140] In summary, a higher hematoma growth rate (a combined measure of time from symptom onset to baseline scan and baseline hematoma volume) and higher diastolic blood pressure predict hematoma expansion in patients with FXa-related ICH, but not thrombotic events. The benefits of Andexanet are robust across these variables and can be further amplified by using these indicators for patient selection. * * *

[0141] The contents of articles, patents and patent applications, and all other documents and electronically available information mentioned or cited in this article are incorporated herein by reference in their entirety, to the extent that each individual publication is specifically and individually indicated to be incorporated by reference.

[0142] The applicant reserves the right to physically incorporate any material and information in any such articles, patents, patent applications or other physical and electronic documents into this application.

[0143] This disclosure is described broadly and generally herein. Each narrower group of species and subgenus falling within the general disclosure also constitutes part of this disclosure. This includes general descriptions of this disclosure with accompanying conditions or negative limitations that remove any subject matter from the genus, regardless of whether the removed material is specifically described herein. Other embodiments are within the scope of the following claims. Furthermore, in describing features or aspects of this disclosure according to the Markush Group, those skilled in the art will recognize that this disclosure is therefore also described in terms of any single member or subgroup of the Markush Group.

Claims

1. A method for improving hemostatic efficacy in a patient with intracranial hemorrhage during anticoagulation therapy with a factor Xa (FXa) inhibitor, comprising administering an FXa derivative to the patient, the FXa derivative being deficient in at least 50% of amino acid residues 6-39 of its light chain and having its active site on the heavy chain modified, wherein the FXa derivative exhibits reduced catalytic activity compared to wild-type FXa protein and is capable of binding the factor Xa inhibitor.

2. The method according to claim 1, wherein the administration is performed within 6 hours after the onset of symptoms of intracranial hemorrhage, or preferably within 3 hours after the onset of symptoms of intracranial hemorrhage.

3. The method according to claim 1 or 2, wherein the administration is performed within 15 hours after the patient takes the FXa inhibitor.

4. The method according to any one of the preceding claims, wherein the administration comprises a bolus injection of the FXa derivative.

5. The method according to claim 4, wherein the bolus injection comprises 300-500 mg of the FXa derivative, or preferably 350-450 mg of the FXa derivative.

6. The method of claim 4 or 5, wherein the administration further comprises infusing the FXa derivative after the bolus injection.

7. The method of claim 6, wherein the infusion comprises 400-560 mg of the FXa derivative, or preferably 450-510 mg of the FXa derivative.

8. The method of claim 7, wherein the anticoagulation therapy comprises 10 mg or less rivaroxaban, 5 mg or less apixaban, 30 mg or less edoxaban, or 40 mg or less enoxaparin.

9. The method of claim 7, wherein the anticoagulation therapy comprises 10 mg or less rivaroxaban, or 5 mg or less apixaban.

10. The method according to any one of the preceding claims, wherein the patient is at least 75 years old.

11. The method according to any one of the preceding claims, wherein the patient's baseline NIHSS (NIH Stroke Scale / Score) is greater than 9.

12. The method according to any one of the preceding claims, wherein the patient has a hematoma growth rate greater than 1 mL / hour after the onset of intracranial hemorrhage symptoms.

13. The method of claim 12, wherein the hematoma growth rate is measured from the time from the onset of intracranial hemorrhage symptoms to baseline imaging or the application of the FXa derivative.

14. The method of claim 12 or 13, wherein the baseline image or the administration of the FXa derivative occurs within 6 hours of the onset of symptoms of intracranial hemorrhage, or within 5, 4, or 3 hours of the onset of symptoms of intracranial hemorrhage.

15. The method according to any one of claims 12-14, wherein the patient has a hematoma growth rate greater than or equal to 11 mL / hour.

16. The method according to any one of the preceding claims, wherein the patient has a diastolic blood pressure greater than 95 mm Hg.

17. A method for selecting patients to receive treatment with factor Xa (FXa) derivatives, comprising: (a) In patients receiving anticoagulation therapy with FXa inhibitors, the baseline hematoma volume was measured after the onset of intracranial hemorrhage symptoms to obtain the hematoma growth rate, which was the baseline hematoma volume divided by the time period from the onset of symptoms to the measurement. and (b) When the hematoma growth rate is greater than 1 mL / hour, the patient is selected to receive FXa derivative treatment. The FXa derivative is missing at least 50% of amino acid residues 6-39 of the light chain and the active site on the heavy chain is modified, and the FXa derivative has reduced catalytic activity compared to wild-type FXa protein and is able to bind to the Xa factor inhibitor.

18. The method of claim 17, further comprising administering the FXa derivative to the selected patient.

19. The method according to any one of the preceding claims, wherein the FXa derivative is a double-chain protein comprising a light chain containing the amino acid sequence of SEQ ID NO:3 or a first peptide having at least 85% sequence identity with SEQ ID NO:3, and a heavy chain containing the amino acid sequence of SEQ ID NO:4 or a second peptide having at least 85% sequence identity with SEQ ID NO:

4.

20. The method of claim 19, wherein the FXa derivative is andexanet alfa.

21. The method according to any one of the preceding claims, wherein the patient is selected to receive treatment with the FXa derivative when the hematoma growth rate is greater than 11 mL / hour.

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