Dosage and administration of anti-C5 antibodies for preventing or minimizing cardiac surgery-related acute kidney injury (CSA-AKI) and / or subsequent major adverse kidney event (MAKE) in patients suffering from chronic kidney disease

Abstract

Provided herein are methods for performing a procedure (e.g., for example, for a human patient in a specific subpopulation (e.g., a human patient with kidney disease, including chronic kidney disease (CKD)). A method of preparing for cardiac surgery using cardiopulmonary shunt (CPB), a method of inhibiting end complement activation in a human patient, a method of treating a human patient suffering from CKD prior to cardiac surgery using CPB, a method of preventing or reducing cardiac surgery-related acute kidney injury (CSA-AKI) in a human patient suffering from CKD, and a method of preventing or reducing cardiac surgery-related acute kidney injury (CSA-AKI) in a human patient suffering from CKD. And methods of preventing or reducing one or more MAKEs in a human patient with CKD. The methods comprise administering to the patient an anti-C5 antibody, e.g., laflizumab or icubezumab, or an antigen-binding fragment thereof, according to a specific clinical dosage regimen and according to a specific schedule.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority and the benefit of U.S. Provisional Application No. 63 / 410,753, filed on September 28, 2022, and U.S. Provisional Application No. 63 / 440,968, filed on January 25, 2023. The entire content of the above applications is incorporated herein by reference. Background of the Invention

[0003] In patients undergoing cardiac surgery with cardiopulmonary bypass (CPB), the presence of chronic kidney disease (CKD) confers a high risk of adverse outcomes, and postoperative acute kidney injury (AKI) further exacerbates these risks (see, for example, Meersch M et al., Current Opinion in Anaesthesiology. 2016; 29(3):413 - 420; Mehta RH et al., Circulation. 2006; 114(21):2208 - 2216; Nashef SA et al., EuroSCORE II. Eur J Cardiothorac Surg. 2012; 41(4):734 - 744; Thakar CV et al., Kidney Int. 2005; 67(3):1112 - 1119; and Thakar CV et al., J. Am. Soc. Nephrol. 2005; 16(1):162 - 168). AKI after CPB is characterized by a sudden deterioration of renal excretory function after cardiac surgery, typically manifested as a decrease in glomerular filtration rate (GFR). AKI occurs in approximately 25% of patients after surgery using CPB (see, for example, Corredor C et al., J. Cardiothorac. Vasc. Anesth. 2016; 30(1):69 - 75; and Hu J et al., J. Cardiothorac. Vasc. Anesth. 2016; 30(1):82 - 89), and in up to 60% to 80% of patients with moderate to severe CKD (calculated according to Priyanka P et al., J. Thorac. Cardiovasc. Surg. 2021; 162(1):143 - 151.e147).

[0004] AKI after CPB is associated with in-hospital mortality, the need for kidney replacement therapy (KRT; also known as renal replacement therapy or RRT), permanent loss of kidney function (risk of progression to CKD, including end-stage kidney disease), high resource utilization, and poor long-term survival (see, e.g., Peng et al., Anesth. Analg. Oct. 1, 2022; 135(4):744-756; Chawla LS et al., N. Engl. J. Med. 2014; 371(1):58-66; Chawla LS et al., Kidney Int. 2011; 79(12):1361-1369; Coca SG et al., Am. J. Kidney Dis. 2009; 53(6):961-973; Dasta JF et al., Nephrology, Dialysis, Transplantation: Official Publication of the European Dialysis and Transplant Association-European Renal Association; 2008; 23(6):1970-1974; Ishani A et al., J. Am. Soc. Nephrol. 2009; 20(1):223-228; Mangano CM et al., The Multicenter Study of Perioperative Ischemia Research Group. Ann Intern Med. 1998; 128(3):194-203; Thakar CV et al., Incidence and outcomes of acute kidney injury in intensive care units: a Veterans Administration study. Crit Care Med. 2009; 37(9):2552-2558). A large meta-analysis showed that the in-hospital mortality rates after cardiac surgery were 1.7% and 10.7% for patients without AKI and those with AKI, respectively. The long-term (1-year - 5-year) mortality rates were 11.9% and 30%, respectively (Hu, 2016).Compared with transient AKI or no AKI, persistent kidney dysfunction (SKD) after AKI multiplies the short- and long-term risks of death (see, e.g., Brown JR et al., Ann. Thorac. Surg. 2010; 90(4): 1142-1148; Corredor C et al., J. Cardiothorac. Vasc. Anesth. 2016; 30(1): 69-75; Swaminathan M et al., Ann. Thorac. Surg. 2010; 89(4): 1098-1104) and increases the risk of new-onset CKD or accelerates the progression of pre-existing CKD (see, e.g., Chawla LS et al., N. Engl. J. Med. 2014; 371(1): 58-66; Chawla LS et al., Kidney Int. 2011; 79(12): 1361-1369; and Kellum JA et al., Nat. Rev. Dis. Primers. 2021; 7(1): 52). In patients with pre-existing CKD, the risk of developing end-stage renal disease after AKI is significantly greater (see, e.g., Ishani A et al., J. Am. Soc. Nephrol. 2009; 20(1): 223-228.2009 and Wu VC et al., Kidney Int. 2011; 80(11): 1222-1230).

[0005] The need for KRT due to AKI after CPB occurs in approximately 2% of patients undergoing cardiac surgery (see, e.g., Hu J et al., J. Cardiothorac. Vasc. Anesth. 2016; 30(1):82 - 89), but appears to increase in those patients with underlying CKD, being 13.3% in severe CKD (see, e.g., Chawla LS et al., J. Am. Soc. Nephrol. 2012; 23(8):1389 - 1397; Mehta RH et al., Circulation. 2006; 114(21):2208 - 2216; Thakar CV et al., Kidney Int. 2005; 67(3):1112 - 1119; Thakar CV et al., J. Am. Soc. Nephrol. 2005; 16(1):162 - 168). In - hospital mortality is very high, ranging from 33% to >50% (see, e.g., Chawla LS et al., J. Am. Soc. Nephrol. 2012; 23(8):1389 - 1397; Dasta JF et al., Nephrology, Dialysis, Transplantation: Official Publication of the European Dialysis and Transplant Association - European Renal Association. 2008; 23(6):1970 - 1974; Landoni G et al., European Journal of Anaesthesiology. 2006; 23(1):17 - 22); and Thakar CV et al., Kidney Int. 2005; 67(3):1112 - 1119; Thakar CV et al., J. Am. Soc. Nephrol. 2005; 16(1):162 - 168).

[0006] Multiple therapeutic approaches have failed to demonstrate a reduction in AKI after CPB or a reduction in adverse clinical outcomes associated with AKI, namely, SKD at risk of progressive CKD, the need for KRT, and mortality (see, e.g., Schurle A et al., J. Clin. Med. 2021; 10(24)). There remains a highly unmet medical need to develop therapies that reduce the risk of AKI and its consequences in patients with CKD undergoing CPB cardiac surgery. Accordingly, an object of the present disclosure is to provide improved methods for preventing and / or minimizing cardiac surgery - associated kidney injury (CSA - AKI) and / or subsequent major adverse kidney events (MAKE) in patients with CKD. SUMMARY OF THE INVENTION

[0007] The present disclosure relates to compositions and methods for preventing and / or treating acute kidney injury (AKI) in human patients with chronic kidney disease (CKD) who undergo cardiopulmonary bypass (CPB). The methods of the invention improve existing treatment modalities, such as intraoperative and postoperative strategies, which are provided in an inpatient setting and target inflammatory mediators of AKI. Compared to current methods for reducing AKI, the compositions and methods of the present disclosure can be administered in an outpatient setting and are effective in preventing AKI and significantly improving clinical outcomes, such as reducing major adverse events and even death, in patients with unmet needs.

[0008] Provided herein are methods for preparing a human patient for surgery (e.g., cardiac surgery using cardiopulmonary bypass (CPB)) in a specific subset (e.g., human patients with kidney disease, including chronic kidney disease (CKD)), which include administering to the patient an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered (or for administration) according to a specific clinical dosing regimen (e.g., as a single weight-based dose) and according to a specific schedule (e.g., at least one to seven calendar days before surgery).

[0009] Also provided herein are methods of inhibiting terminal complement activation in a human patient, methods of treating a human patient with CKD prior to cardiac surgery using CPB, methods of preventing or reducing (e.g., minimizing) cardiac surgery-associated acute kidney injury (CSA-AKI) in a human patient with CKD, and methods of preventing or reducing (e.g., minimizing) one or more major adverse kidney events (MAKE) in a human patient with CKD.

[0010] Any suitable anti-C5 antibody or an antigen-binding fragment thereof can be used in the methods described herein. An exemplary anti-C5 antibody is ravulizumab, which comprises a heavy chain and a light chain having the sequences shown in SEQ ID NO: 14 and 11, respectively, or an antigen-binding fragment and variant thereof. In other embodiments, the antibody comprises the heavy and light chain complementarity determining regions (CDRs) or variable regions (VRs) of ravulizumab. Thus, in one embodiment, the antibody comprises the CDR1, CDR2, and CDR3 domains of the heavy chain variable (VH) region of ravulizumab having the sequence shown in SEQ ID NO:12, and the CDR1, CDR2, and CDR3 domains of the light chain variable (VL) region of ravulizumab having the sequence shown in SEQ ID NO:8. In another embodiment, the antibody comprises CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NOs:19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NOs:4, 5, and 6, respectively. In another embodiment, the antibody comprises VH and VL regions having the amino acid sequences shown in SEQ ID NOs:12 and SEQ ID NO:8, respectively. In another embodiment, the antibody comprises a heavy chain constant region as shown in SEQ ID NO:13.

[0011] In another embodiment, the antibody comprises a variant human Fc constant region that binds to the human neonatal Fc receptor (FcRn), wherein the variant human Fc CH3 constant region comprises Met429Leu and Asn435Ser substitutions at residues corresponding to methionine 428 and asparagine 434 of the native human IgG Fc constant region, respectively, according to the EU numbering convention.

[0012] In another embodiment, the antibody comprises CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NOs:19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NOs:4, 5, and 6, respectively, and a variant human Fc constant region that binds to the human neonatal Fc receptor (FcRn), wherein the variant human Fc CH3 constant region comprises Met429Leu and Asn435Ser substitutions at residues corresponding to methionine 428 and asparagine 434 of the native human IgG Fc constant region, respectively, according to the EU numbering convention.

[0013] In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the BNJ421 antibody (described in WO2015134894 and U.S. Patent No. 9,079,949). In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the 7086 antibody (see U.S. Patent Nos. 8,241,628 and 8,883,158). In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the 8110 antibody (see U.S. Patent Nos. 8,241,628 and 8,883,158). In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the 305LO5 antibody (see U.S. Patent No. 9,765,135). In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the SKY59 antibody. In another embodiment, the anti-C5 antibody comprises the heavy and light chain CDRs or variable regions of the REGN3918 antibody.

[0014] In another embodiment, the anti-C5 antibody is a biosimilar of eculizumab For example, in one embodiment, the anti-C5 antibody is, for example, the ABP 959 antibody (manufactured by Amgen Inc.), (manufactured by Generium JNC, Russia), SB12 (manufactured by Samsung Bioepis, Incheon, Korea), ISU305 (a biosimilar of eculizumab from ISU Abxis, Korea), (a biosimilar of eculizumab from CinnaGen, Iran), BCD 148 (a biosimilar of eculizumab from Biocad Medical, Quebec, Canada), tesidolumab (manufactured by Novartis), Crovalimab (manufactured by Roche), CAN106 (manufactured by CanBridge Pharmaceuticals, Beihai, China) or Pozelimab (manufactured by Regeneron).

[0015] In another embodiment, the antibody competes with any of the above antibodies for binding to the same epitope on C5. In another embodiment, the antibody has at least about 90% variable region amino acid sequence identity with any of the above antibodies (e.g., at least about 90%, 95% or 99% variable region identity with SEQ ID NO:12 or SEQ ID NO:8).

[0016] In another embodiment, the antibody has a K of 0.1 nM ≤ at pH 7.4 and 25 °CD The affinity dissociation constant (K D ) binds to human C5 within the range of ≤ 1 nM. In another embodiment, the antibody binds to human C5 with an affinity dissociation constant (K D ) of approximately 0.5 nM at pH 7.4 and 25°C. In another embodiment, the antibody binds to human C5 with a K D ≥ 10 nM at pH 6.0 and 25°C. In another embodiment, the antibody binds to human C5 with a K D of approximately 22 nM at pH 6.0 and 25°C. In yet another embodiment, [(K D of the antibody or its antigen-binding fragment for human C5 at pH 6.0 and 25°C) / (K D of the antibody or its antigen-binding fragment for human C5 at pH 7.4 and 25°C)] of the antibody is greater than 25.

[0017] The methods described herein can be used for any type of cardiac surgery. In another embodiment, the cardiac surgery is coronary artery bypass grafting (CABG). In another embodiment, the surgery is valve replacement or repair. In another embodiment, the surgery is the insertion of a pacemaker or an implantable cardioverter defibrillator (ICD). In another embodiment, the surgery is maze surgery. In another embodiment, the surgery is a heart transplant. In another embodiment, the surgery is the insertion of a ventricular assist device (VAD). In another embodiment, the surgery is the insertion of a total artificial heart (TAH). In another embodiment, the surgery is the insertion of a transcatheter structural heart surgery. In a specific embodiment, the surgery is cardiac surgery using CPB.

[0018] In one embodiment, the anti-C5 antibody or its antigen-binding fragment is administered to the patient at least one calendar day before the surgery (e.g., cardiac surgery using CPB). In another embodiment, the anti-C5 antibody or its antigen-binding fragment is administered one to seven calendar days before the surgery. For example, in one embodiment, the anti-C5 antibody or its antigen-binding fragment is administered one, two, three, four, five, six, or seven calendar days before the surgery.

[0019] These anti-C5 antibodies or antigen-binding fragments thereof are administered to a patient (e.g., a single preoperative weight-based dose) at a weight-based dose according to the methods described herein. In one embodiment, an anti-C5 antibody or antigen-binding fragment thereof is administered at a dose of 2700 mg to a patient weighing ≥30 kg to <40 kg. In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is administered at a dose of 3000 mg to a patient weighing ≥40 kg to <60 kg. In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is administered at a dose of 3300 mg to a patient weighing ≥60 kg to <100 kg. In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is administered at a dose of 3600 mg to a patient weighing ≥100 kg.

[0020] In one aspect, there is provided a method of preparing a human patient (e.g., a human patient suffering from a kidney disease, including CKD) for surgery (e.g., cardiac surgery using CPB), the method comprising administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery.

[0021] In one embodiment, there is provided a method of preparing a human patient with CKD for cardiac surgery using CPB, the method comprising administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0022] a) 2700 mg for patients weighing ≥30 kg to <40 kg;

[0023] b) 3000 mg for patients weighing ≥40 kg to <60 kg;

[0024] c) 3300 mg for patients weighing ≥60 kg to <100 kg; or

[0025] d) 3600 mg for patients weighing ≥100 kg.

[0026] In another aspect, there is provided a method of inhibiting terminal complement activation in a human patient (such as a human patient suffering from kidney disease, including CKD) prior to surgery (such as cardiac surgery using CPB), wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2 and CDR3 heavy chain sequences as shown in SEQ ID NOs: 19, 18 and 3, respectively, and CDR1, CDR2 and CDR3 light chain sequences as shown in SEQ ID NOs: 4, 5 and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery.

[0027] In one embodiment, there is provided a method of inhibiting terminal complement activation in a human patient with CKD prior to cardiac surgery using CPB, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2 and CDR3 heavy chain sequences as shown in SEQ ID NOs: 19, 18 and 3, respectively, and CDR1, CDR2 and CDR3 light chain sequences as shown in SEQ ID NOs: 4, 5 and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0028] a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg;

[0029] b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg;

[0030] c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or

[0031] d) 3600 mg for patients with a body weight of ≥ 100 kg.

[0032] In some embodiments, terminal complement activation is inhibited in a human patient according to the methods described herein, as evaluated by any suitable assay. In one embodiment, the method inhibits terminal complement activation in a human patient, such as inhibiting 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100%.

[0033] In another aspect, a method of treating a human patient having a kidney disease (e.g., CKD) prior to a cardiac surgery (e.g., a cardiac surgery using CPB) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or the antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or the antigen-binding fragment thereof is administered once before the surgery.

[0034] In one embodiment, a method of treating a human patient having CKD prior to a cardiac surgery using CPB is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or the antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or the antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0035] a) 2700 mg for patients weighing ≥30 kg to <40 kg;

[0036] b) 3000 mg for patients weighing ≥40 kg to <60 kg;

[0037] c) 3300 mg for patients weighing ≥60 kg to <100 kg; or

[0038] d) 3600 mg for patients weighing ≥100 kg.

[0039] In another aspect, a method of preventing or reducing (e.g., minimizing) CSA-AKI in a human patient having a kidney disease (e.g., CKD) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or the antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or the antigen-binding fragment thereof is administered once before a cardiac surgery (e.g., a cardiac surgery using CPB).

[0040] In one embodiment, a method of preventing or reducing (e.g., minimizing) CSA-AKI in a human patient with CKD is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once prior to cardiac surgery (e.g., cardiac surgery using CPB) at the following doses:

[0041] a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg;

[0042] b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg;

[0043] c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or

[0044] d) 3600 mg for patients with a body weight of ≥100 kg.

[0045] In another aspect, a method of preventing or reducing (e.g., minimizing) one or more MAKEs in a human patient with kidney disease (e.g., CKD) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once prior to cardiac surgery (e.g., cardiac surgery using CPB).

[0046] In one embodiment, a method of preventing or reducing (e.g., minimizing) one or more MAKEs in a human patient with CKD is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once prior to cardiac surgery (e.g., cardiac surgery using CPB) at the following doses:

[0047] a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg;

[0048] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0049] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0050] d) 3600 mg for patients weighing ≥ 100 kg.

[0051] In certain embodiments, the methods described herein provide an optimal desired response (e.g., inhibiting terminal complement activation in a human patient (e.g., a human patient with a kidney disease, including CKD) prior to surgery (e.g., cardiac surgery using CPB), preventing or reducing CSA-AKI in a human patient with a kidney disease (e.g., CKD) undergoing surgery (e.g., cardiac surgery using CPB), and / or preventing or reducing one or more MAKEs in a human patient with a kidney disease (e.g., CKD) undergoing surgery (e.g., cardiac surgery using CPB)).

[0052] In certain embodiments, the methods described herein are sufficient to maintain a specific serum trough concentration of an anti-C5 antibody or an antigen-binding fragment thereof. In one embodiment, for example, the method maintains the serum trough concentration of the anti-C5 antibody or an antigen-binding fragment thereof at 50 μg / mL, 55 μg / mL, 60 μg / mL, 65 μg / mL, 70 μg / mL, 75 μg / mL, 80 μg / mL, 85 μg / mL, 90 μg / mL, 95 μg / mL, 100 μg / mL, 105 μg / mL, 110 μg / mL, 115 μg / mL, 120 μg / mL, 125 μg / mL, 130 μg / mL, 135 μg / mL, 140 μg / mL, 145 μg / mL, 150 μg / mL, 155 μg / mL, 160 μg / mL, 165 μg / mL, 170 μg / mL, 175 μg / mL, 180 μg / mL, 185 μg / mL, 190 μg / mL, 200 μg / mL, 205 μg / mL, 210 μg / mL, 215 μg / mL, 220 μg / mL, 225 μg / mL, 230 μg / mL, 240 μg / mL, 245 μg / mL, 250 μg / mL, 255 μg / mL, 260 μg / mL, 265 μg / mL, 270 μg / mL, 280 μg / mL, 290 μg / mL, 300 μg / mL, 305 μg / mL, 310 μg / mL, 315 μg / mL, 320 μg / mL, 325 μg / mL, 330 μg / mL, 335 μg / mL, 340 μg / mL, 345 μg / mL, 350 μg / mL, 355 μg / mL, 360 μg / mL, 365 μg / mL, 370 μg / mL, 375 μg / mL, 380 μg / mL, 385 μg / mL, 390 μg / mL, 395 μg / mL, 400 μg / mL, 405 μg / mL, 410 μg / mL, 415 μg / mL, 420 μg / mL, 425 μg / mL, 430 μg / mL, 435 μg / mL, 440 μg / mL, 445 μg / mL, 450 μg / mL, 455 μg / mL, 460 μg / mL, 465 μg / mL, 470 μg / mL, 475 μg / mL, 480 μg / mL, 485 μg / mL, 490 μg / mL, 495 μg / mL, 500 μg / mL, 505 μg / mL, 510 μg / mL, 515 μg / mL, 520 μg / mL, 525 μg / mL, 530 μg / mL, 535 μg / mL, 540 μg / mL, 545 μg / mL, 550 μg / mL, 555 μg / mL, 560 μg / mL, 565 μg / mL, 570 μg / mL, 575 μg / mL, 580 μg / mL, 585 μg / mL,590 μg / mL, 595 μg / mL, 600 μg / mL, 605 μg / mL, 610 μg / mL, 615 μg / mL, 620 μg / mL, 625 μg / mL, 630 μg / mL, 635 μg / mL, 640 μg / mL, 645 μg / mL, 650 μg / mL, 655 μg / mL, 660 μg / mL, 665 μg / mL, 670 μg / mL, 675 μg / mL, 680 μg / mL, 685 μg / mL, 690 μg / mL, 695 μg / mL, 700 μg / mL or greater. In one embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment at 100 μg / mL or greater, 150 μg / mL or greater, 200 μg / mL or greater, 250 μg / mL or greater, 300 μg / mL or greater, 350 μg / mL or greater, 400 μg / mL or greater, or 450 μg / mL or greater. In another embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment between 100 μg / mL and 700 μg / mL, preferably between 300 μg / mL and 600 μg / mL. In another embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment at about 475 μg / mL. In another embodiment, the method maintains the peak serum concentration of the anti-C5 antibody or its antigen-binding fragment at less than about 1800 μg / mL, 1780 μg / mL, 1760 μg / mL, 1740 μg / mL, 1720 μg / mL, 1700 μg / mL, 1680 μg / mL, 1660 μg / mL, 1640 μg / mL, 1620 μg / mL, 1600 μg / mL, 1580 μg / mL, 1560 μg / mL, 1540 μg / mL, 1520 μg / mL, 1500 μg / mL, 1480 μg / mL, 1460 μg / mL, 1440 μg / mL, 1420 μg / mL, 1400 μg / mL, 1380 μg / mL, 1360 μg / mL, 1340 μg / mL, 1320 μg / mL, 1300 μg / mL, 1280 μg / mL, 1260 μg / mL, 1240 μg / mL, 1220 μg / mL, 1200 μg / mL, 1180 μg / mL, 1160 μg / mL, 1140 μg / mL, 1120 μg / mL, 1100 μg / mL, 1080 μg / mL, 1060 μg / mL, 1040 μg / mL, 1020 μg / mL, 1000 μg / mL, 980 μg / mL, 960 μg / mL, 940 μg / mL,920 μg / mL or 900 μg / mL or less. In other embodiments, the method maintains the peak serum concentration of the anti-C5 antibody or antigen-binding fragment thereof between 900 μg / mL and 1800 μg / mL, preferably between 1050 μg / mL and 1550 μg / mL. In another embodiment, the method maintains a peak serum concentration of the anti-C5 antibody or antigen-binding fragment thereof of about 1350 μg / mL.

[0053] In another embodiment, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains at least 50 μg, 55 μg, 60 μg, 65 μg, 70 μg, 75 μg, 80 μg, 85 μg, 90 μg, 95 μg, 100 μg, 105 μg, 110 μg, 115 μg, 120 μg, 125 μg, 130 μg, 135 μg, 140 μg, 145 μg, 150 μg, 155 μg, 160 μg, 165 μg, 170 μg, 175 μg, 180 μg, 185 μg, 190 μg, 195 μg, 200 μg, 205 μg, 210 μg, 215 μg, 220 μg, 225 μg, 230 μg, 235 μg, 240 μg, 245 μg, 250 μg, 255 μg, 260 μg, 270 μg, 280 μg, 290 μg, 300 μg, 320 μg, 340 μg, 360 μg, 380 μg, 400 μg, 420 μg, 440 μg, 460 μg, 480 μg, 500 μg, 550 μg, 600 μg, 650 μg, 700 μg, 750 μg, 800 μg, 850 μg, 900 μg, 950 μg, 1000 μg, 1050 μg, 1100 μg, 1150 μg, 1200 μg, 1250 μg, 1300 μg, 1350 μg, 1400 μg, 1450 μg, 1500 μg, 1550 μg, 1600 μg, 1650 μg, 1700 μg, 1750 μg or more, such as 1800 μg of the antibody.

[0054] In another embodiment, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains the lowest free C5 concentration. In one embodiment, for example, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains a free C5 concentration of 0.5 μg / mL or lower (e.g., 0.4 μg / mL, 0.3 μg / mL, 0.2 μg / mL or 0.1 μg / mL or lower).

[0055] The anti-C5 antibody or antigen-binding fragment thereof can be administered to a patient by any suitable means. In one embodiment, the antibody is formulated for intravenous administration.

[0056] The efficacy of the methods provided herein can be evaluated using any suitable means. In one embodiment, a single preoperative weight-based dose of an anti-C5 antibody or an antigen-binding fragment thereof results in complete C5 inhibition for at least 18 days.

[0057] In another embodiment, the method prevents the need for renal replacement therapy (KRT).

[0058] In another embodiment, the method prevents or reduces CSA-AKI in human patients with CKD. In one embodiment, CSA-AKI is characterized by an increase in:

[0059] a) Serum creatinine (sCr) or serum cystatin C (sCysC) ≥ 0.3 mg / dL within a 48-hour period within 7 days after CPB, and / or

[0060] b) sCr or sCysC ≥ 1.5-fold baseline within 7 days after CPB or on days 15, 30, 60, or 90 after CPB.

[0061] In another embodiment, after treatment, based on the highest sCr observed within 7, 30, 45, 60, or 90 days after CPB, the human patient does not have severe CSA-AKI (stage 2 or 3),

[0062] as evaluated by the improved Kidney Disease: Improving Global Outcomes (KDIGO) criteria.

[0063] In another embodiment, after treatment, based on the highest sCr observed within 7, 30, 45, 60, or 90 days after CPB, the human patient does not have severe CSA-AKI, as evaluated by the improved "Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease" (RIFLE) criteria.

[0064] In another embodiment, the method results in complete recovery from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the complete recovery is characterized by sCr < 1.1 × baseline.

[0065] In another embodiment, the method results in partial recovery from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the partial recovery is characterized by sCr ≥ 1.1 - < 1.5 × baseline.

[0066] In another embodiment, the method results in improvement from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the improvement is characterized by sCr ≥ 1.5 - < 2.0 × baseline.

[0067] In another embodiment, the method results in stable CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, characterized by sCr ≥ 2.0 - < 3.0 × baseline.

[0068] In another embodiment, the method prevents or reduces one or more MAKEs in human patients with CKD. In one embodiment, one or more MAKEs is persistent kidney dysfunction (SKD), which is defined as, for example, an estimated glomerular filtration rate (eGFR) > 25% lower than baseline after CPB, where the decrease in eGFR is determined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula based on serum cystatin C (sCysC) or serum creatinine (sCr). In another embodiment, one or more MAKEs is the occurrence of kidney replacement therapy (KRT) after CPB. In another embodiment, one or more MAKEs is death from any cause after CPB.

[0069] In another embodiment, the method results in a change in quality of life from baseline as evaluated via quality of life assessment. For example, in one embodiment, the quality of life assessment is the Kidney Disease Quality of Life Short Form (KDQOL-36). In another embodiment, the quality of life assessment is the 5-dimension 5-level (EQ-5D-5L) of the EuroQol Group. In another embodiment, the quality of life assessment is the Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue Scale.

[0070] In another embodiment, the method results in a shift of biomarkers associated with vascular inflammation (e.g., soluble tumor necrosis factor receptor 1 [TNF-R1 or sTNF-R1]) to normal levels. In another embodiment, the method results in a shift of biomarkers associated with endothelial injury and / or activation (e.g., thrombomodulin) to normal levels. In another embodiment, the method results in a shift of biomarkers associated with kidney injury (e.g., neutrophil gelatinase-associated lipocalin [NGAL]) to normal levels. In another embodiment, the method results in a shift of biomarkers associated with inducers of cell cycle arrest (e.g., tissue inhibitor of metalloproteinase-2 [TIMP-2]) to normal levels. In another embodiment, the method results in a shift of complement proteins and complement activation pathway products (e.g., soluble C5b-9) to normal levels.

[0071] There is further provided a kit that includes a therapeutically effective amount of a pharmaceutical composition suitable for use in the methods described herein, the pharmaceutical composition containing an anti-C5 antibody or an antigen-binding fragment thereof such as eculizumab or ravulizumab and a pharmaceutically acceptable carrier.

[0072] In one embodiment, the kit comprises: (a) a dose of an anti-C5 antibody or an antigen-binding fragment thereof, the CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and the CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and (b) instructions for using the anti-C5 antibody or an antigen-binding fragment thereof in the methods described herein.

[0073] In another aspect, there is provided an anti-C5 antibody or an antigen-binding fragment thereof (e.g., ravulizumab ) for preparing a human patient with CKD for cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses, e.g., as a single dose, before the surgery:

[0074] a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg;

[0075] b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg;

[0076] c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or

[0077] d) 3600 mg for patients with a body weight of ≥ 100 kg.

[0078] In another embodiment, there is provided an anti-C5 antibody or an antigen-binding fragment thereof for inhibiting terminal complement activation in a human patient with CKD before cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses, e.g., as a single dose, before the surgery:

[0079] a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg;

[0080] b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg;

[0081] c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or

[0082] d) 3600 mg for patients with a body weight of ≥ 100 kg.

[0083] In another embodiment, there is provided an anti-C5 antibody or an antigen-binding fragment thereof for treating a human patient with CKD before cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses, e.g., as a single dose, before the surgery:

[0084] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0085] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0086] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0087] d) 3600 mg for patients weighing ≥ 100 kg.

[0088] In another embodiment, an anti-C5 antibody or an antigen-binding fragment thereof is provided for preventing or reducing CSA-AKI in human patients with CKD, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses before surgery:

[0089] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0090] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0091] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0092] d) 3600 mg for patients weighing ≥ 100 kg.

[0093] In another embodiment, an anti-C5 antibody or an antigen-binding fragment thereof is provided for preventing or reducing one or more MAKEs in human patients with CKD, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses before surgery:

[0094] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0095] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0096] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0097] d) 3600 mg for patients weighing ≥ 100 kg.

[0098] In another aspect, the present invention provides the use of an anti-C5 antibody or an antigen-binding fragment thereof (e.g., ravulizumab ) for preparing a human patient with CKD for a cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses before surgery:

[0099] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0100] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0101] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0102] d) 3600 mg for patients weighing ≥ 100 kg.

[0103] In one embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for inhibiting terminal complement activation in a human patient with CKD prior to cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses prior to surgery:

[0104] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0105] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0106] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0107] d) 3600 mg for patients weighing ≥ 100 kg.

[0108] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for treating a human patient with CKD prior to cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses prior to surgery:

[0109] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0110] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0111] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0112] d) 3600 mg for patients weighing ≥ 100 kg.

[0113] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing CSA-AKI in a human patient with CKD, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, for example, as a unit dose, at the following doses prior to surgery:

[0114] a) 2700 mg for patients weighing ≥30 kg to <40 kg;

[0115] b) 3000 mg for patients weighing ≥40 kg to <60 kg;

[0116] c) 3300 mg for patients weighing ≥60 kg to <100 kg; or

[0117] d) 3600 mg for patients weighing ≥100 kg.

[0118] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing one or more MAKEs in human patients with chronic kidney disease, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once, preoperatively, at the following doses, for example, as a unit dose:

[0119] a) 2700 mg for patients weighing ≥30 kg to <40 kg;

[0120] b) 3000 mg for patients weighing ≥40 kg to <60 kg;

[0121] c) 3300 mg for patients weighing ≥60 kg to <100 kg; or

[0122] d) 3600 mg for patients weighing ≥100 kg. BRIEF DESCRIPTION OF THE DRAWINGS

[0123] Figure 1 is a schematic diagram of a clinical trial protocol.

[0124] Figures 2A to 2G Lists the activity schedule of the clinical trial protocol described in Example 1. The following abbreviations are used in the activity schedule: ADA = anti-drug antibody; AE = adverse event; AKI = acute kidney injury; CPB = cardiopulmonary bypass; CT = computed tomography; D and d = days; ECG = electrocardiogram; ED = early discontinuation; eGFR = estimated glomerular filtration rate; EQ 5D 5L = 5-dimensional 5-level of the European Quality of Life Group; FACIT Fatigue = Functional Assessment of Chronic Illness Therapy - Fatigue; FSH = follicle-stimulating hormone; ICU = intensive care unit; KDQOL 36 = Kidney Disease Quality of Life Short Form - 36 items; KRT = kidney replacement therapy; PD = pharmacodynamics; PK = pharmacokinetics; pRBC = packed red blood cells; sCysC = serum cystatin C; RBC = red blood cells; STS = Society of Thoracic Surgeons; and WOCBP = women of childbearing potential. DETAILED DESCRIPTION

[0125] I. Definitions

[0126] As used herein, the terms "subject" or "patient" are human patients (e.g., patients suffering from kidney disease, such as chronic kidney disease).

[0127] As used herein, the term "pediatric" patient is a human patient who has been classified by a physician or caregiver as belonging to a non - adult category and may include, for example, neonates (both premature and full - term), infants, children, and adolescents. Generally, a pediatric patient is a patient less than 18 years of age (< 18 years).

[0128] As used herein, the term "adult" patient is a human patient who has been classified by a physician or caregiver, etc., as, for example, a non - neonate, infant, child, or adolescent, based on, for example, age, developmental status, physiological characteristics, etc. Generally, an adult patient is a patient 18 years of age or older (≥ 18 years).

[0129] As used herein, the phrase "chronic kidney disease" (CKD) (also known as chronic renal disease) is a condition characterized by a gradual loss of kidney function over time. Diabetes and high blood pressure (hypertension) are responsible for two - thirds of cases of chronic kidney disease. Other conditions or circumstances that can cause kidney disease include, but are not limited to, glomerulonephritis, genetic diseases (such as polycystic kidney disease (PKD)), prenatal kidney and urinary tract abnormalities, autoimmune diseases, or other causes such as obstruction caused by kidney stones or tumors, prostate enlargement in men, or recurrent urinary tract infections. Symptoms of CKD include, but are not limited to, feeling tired and having less energy, difficulty concentrating, loss of appetite, trouble sleeping, muscle cramps at night, swelling in the feet and ankles, swelling around the eyes, dry skin, itching, and / or the need to urinate more frequently, especially at night.

[0130] CKD is typically diagnosed by one or more of the following tests. One test is the urine albumin - to - creatinine ratio test. Albumin is a protein that should not be found in urine and indicates kidney function problems. Another test is a blood test for creatinine. This test determines whether there is too much creatinine (a waste product) in the blood. A third option is to test the patient's glomerular filtration rate (GFR). The GFR is calculated using the test results and other factors such as age and gender. The result of the GFR is the best way to measure the level of a patient's kidney function and to determine the stage of kidney disease.

[0131] As used herein, the phrase "major adverse kidney event" (MAKE) means: (1) sustained kidney dysfunction (SKD), which is defined as an estimated glomerular filtration rate (eGFR) >25% lower than baseline after CPB (e.g., where the decrease in eGFR is determined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula based on serum cystatin C (sCysC) or serum creatinine (sCr)), (2) the occurrence of kidney replacement therapy (KRT) after CPB, and / or (3) death from any cause after CPB.

[0132] As used herein, the phrase "cardiac surgery-associated acute kidney injury" (CSA-AKI) is an event characterized by a sudden deterioration in kidney function after cardiac surgery, where the decrease in GFR is evident. CSA-AKI is the second most common cause of AKI in the intensive care setting and is associated with increased mortality. The pathophysiology of CSA-AKI is very complex and may include renal ischemia-reperfusion injury, inflammation, oxidative stress, hemolysis, and / or nephrotoxins.

[0133] CSA-AKI is characterized by the following increases: serum creatinine (sCr) or serum cystatin C (sCysC) ≥0.3 mg / dL within a 48-hour period within 7 days after CPB and / or sCr or sCysC ≥1.5-fold baseline within 7 days after CPB. Severe CSA-AKI refers to stage 2 or 3 according to the improved Kidney Disease: Improving Global Outcomes (KDIGO) criteria. A human patient is considered to have no severe CSA-AKI based on the highest sCr observed after CPB (e.g., within 7, 30, 45, 60, or 90 days after CPB), as evaluated by the improved "Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease" (RIFLE) criteria. Complete recovery from CSA-AKI is characterized by sCr <1.1× baseline after CPB (e.g., within 7, 30, 45, 60, or 90 days after CPB). Partial recovery from CSA-AKI is characterized by sCr ≥1.1 - <1.5× baseline (e.g., within 7, 30, 45, 60, or 90 days after CPB). Improvement from CSA-AKI is characterized by sCr ≥1.5 - <2.0× baseline (e.g., within 7, 30, 45, 60, or 90 days after CPB). Stable CSA-AKI is characterized by sCr ≥2.0 - <3.0× baseline (e.g., within 7, 30, 45, 60, or 90 days after CPB).

[0134] As used herein, the phrase "heart surgery" (also known as cardiovascular surgery or heart surgery) refers to any surgical procedure involving the heart or the blood vessels that carry blood to and from the heart. Examples of heart surgery include, but are not limited to, coronary artery bypass grafting (CABG), valve replacement or repair, insertion of a pacemaker or implantable cardioverter defibrillator (ICD), maze surgery, heart transplantation, and insertion of a ventricular assist device (VAD) or total artificial heart (TAH), as well as transcatheter structural heart surgery.

[0135] CABG (also known as coronary artery bypass or coronary artery bypass surgery) is one of the most common types of heart surgery and involves taking a healthy artery or vein from elsewhere in the body and connecting it to supply blood through a blocked coronary artery. The transplanted artery or vein bypasses the blocked portion of the coronary artery, creating a new path for blood flow to the heart muscle. Typically, this is done for more than one coronary artery during the same surgery.

[0136] In the case of heart valve repair or replacement, the surgeon either repairs the valve or replaces it with an artificial valve or a bioprosthetic valve made from pig, cow, or human heart tissue. One repair option is to insert a catheter through a large blood vessel, guide it to the heart, and inflate and deflate a small balloon at the tip of the catheter to widen a narrowed valve.

[0137] Medication is usually the first treatment option for arrhythmia, a condition in which the heart beats too fast, too slow, or with an irregular rhythm. If medication does not work, the surgeon may implant a pacemaker or ICD under the skin of the chest or abdomen and connect it to the ventricles with wires. When the sensor detects an abnormal heart rhythm, the device uses electrical pulses to control the heart rhythm. The ICD works similarly, but when it detects a dangerous arrhythmia, it sends an electric shock to restore a normal rhythm.

[0138] In the case of maze surgery, the surgeon creates a pattern of scar tissue in the upper chambers of the heart to redirect electrical signals along a controlled path to the lower ventricles. The surgery blocks errant electrical signals that cause atrial fibrillation, the most common type of serious arrhythmia.

[0139] During aneurysm repair, a weak portion of an artery or the heart wall is replaced with a patch or graft to repair a balloon-like bulge in the artery or heart muscle wall.

[0140] During a heart transplant, the diseased heart is removed and replaced with a healthy heart from a deceased donor.

[0141] A VAD is a mechanical pump that supports heart function and blood flow. A TAH replaces the two lower chambers of the heart.

[0142] In addition to these surgeries, a minimally invasive alternative form of open-heart surgery that is becoming more common is transcatheter structural heart surgery. This involves guiding a long, flexible tube called a catheter through blood vessels to the heart, which can be accessed from the groin, thigh, abdomen, chest, neck, or clavicle. Small incisions are required. This type of surgery includes transcatheter aortic valve implantation to replace a defective aortic valve with a valve made of animal tissue, placement for mitral valve abnormalities placement, and placement for patients with non-valvular atrial fibrillation placement.

[0143] As used herein, "cardiopulmonary bypass" (CPB) refers to the heart-lung machine used during heart surgery. CPB provides heart and lung support to the patient while bypassing the heart and lungs. CPB artificially provides three physiological processes or functions to the patient: (1) adding oxygen to the blood, (2) pumping or circulating the blood through the cardiopulmonary bypass circuit and the patient, and (3) removing excess carbon dioxide from the blood. To achieve this, the surgeon inserts cannulas into the patient's main veins (usually the superior vena cava and the inferior vena cava) and arteries (usually the aorta). Once the cannulas from the patient have been connected to the cardiopulmonary bypass circuit, blood is drained from the veins into the heart-lung machine while the blood is pumped into an artificial lung (oxygenator), which adds oxygen and removes carbon dioxide. The oxygenated blood is pumped back into the aorta to provide oxygen to the patient's tissues and organs. CPB may include a sternotomy and / or aortic cross-clamping.

[0144] As used herein, "effective treatment" refers to a treatment that produces a beneficial effect, e.g., improvement of at least one symptom of a disease or disorder. The beneficial effect may take the form of an improvement relative to a baseline, e.g., an improvement relative to a measurement or observation made before the start of the therapy according to the method.

[0145] The term "effective amount" refers to the amount of an agent that provides a desired result (e.g., a biological, therapeutic, and / or prophylactic result). The result may be the prevention, reduction, improvement, alleviation, mitigation, delay, and / or remission of one or more of the signs, symptoms, or causes of an event or disease, or any other desired alteration of a biological system. The effective amount may be administered in one or more administrations.

[0146] As used herein, the term "serum trough level" refers to the lowest level of an agent (e.g., an anti-C5 antibody or an antigen-binding fragment thereof) or a drug present in the serum. In contrast, "peak serum level" refers to the highest level of an agent in the serum. "Average serum level" refers to the average level of an agent in the serum over time.

[0147] The term "antibody" describes a polypeptide comprising at least one antibody-derived antigen-binding site (e.g., VH / VL region or Fv or CDR). Antibodies include known forms of antibodies. For example, an antibody can be a human antibody, a humanized antibody, a bispecific antibody, or a chimeric antibody. An antibody can also be a Fab, Fab'2, ScFv, SMIP, affibody, nanobody, or single-domain antibody. An antibody can also be any of the following isotypes: IgG1, IgG2, IgG3, IgG4, IgM, IgA1, IgA2, IgAsec, IgD, IgE, or a combination thereof. The antibody can be a naturally occurring antibody or an antibody altered by protein engineering techniques (e.g., by mutation, deletion, substitution, conjugation with a non-antibody moiety). An antibody can include, for example, one or more variant amino acids that alter the properties of the antibody (e.g., functional properties) compared to a naturally occurring antibody. Many such alterations are known in the art and affect, for example, the half-life in a patient, effector function, and / or the immune response to the antibody. The term antibody also includes artificial or engineered polypeptide constructs comprising at least one antibody-derived antigen-binding site.

[0148] II. Anti-C5 Antibodies

[0149] The anti-C5 antibodies described herein bind to complement component C5 (e.g., human C5) and inhibit the cleavage of C5 into fragments C5a and C5b. As described above, such antibodies also have, for example, improved pharmacokinetic properties compared to other anti-C5 antibodies (e.g., eculizumab) used for therapeutic purposes.

[0150] Anti-C5 antibodies (or VH / VL domains derived therefrom) suitable for use in the methods described herein can be produced using methods known in the art. Alternatively, anti-C5 antibodies recognized in the art can be used. Antibodies that compete with any of these art-recognized antibodies or the antibodies described herein for binding to C5 can also be used.

[0151] An exemplary anti-C5 antibody is ravulizumab, which comprises a heavy chain and a light chain having the sequences shown in SEQ ID NO: 14 and SEQ ID NO: 11, respectively, or an antigen-binding fragment and variant thereof. Ravulizumab (also known as BNJ441 and ALXN1210 are described in WO2015134894 and U.S. Patent No. 9,079,949, the entire teachings of which are hereby incorporated by reference. The terms ravulizumab, BNJ441, and ALXN1210 are used interchangeably throughout the document and all refer to the same antibody. Ravulizumab selectively binds to human complement protein C5 and inhibits the cleavage of human complement protein C5 into C5a and C5b during complement activation. This inhibition prevents the release of the pro-inflammatory mediator C5a and the formation of the lytic pore-forming membrane attack complex (MAC) C5b-9, while preserving the proximal or early components of complement activation (e.g., C3 and C3b) necessary for opsonization of microorganisms and clearance of immune complexes.

[0152] The polypeptide sequence of ravulizumab registered in the KEGG DRUG database (https: / / www.kegg.jp / entry / D11054) specifies that the N-terminal amino acid of the variable heavy chain is "X", but the database does not state what X is. The Chemical Abstracts (CAS) of ravulizumab (CAS 1803171-55-2) also provides that the N-terminal X is pyroglutamic acid (designated as "Chain 1 pyroglutamic acid-1" in the CAS report). Although this information may appear different from the VH sequence of ravulizumab (e.g., the heavy chain variable region polypeptide containing the amino acid sequence shown in SEQ ID NO:12 and / or the heavy chain polypeptide containing the amino acid sequence shown in SEQ ID NO:14), there is an alignment between the patent sequence and the drug database / CAS sequence because it is well recognized in the art that the N-terminal Q in a polypeptide and / or antibody sequence cyclizes during process development to result in a nearly 100% conversion of the drug product to pyroglutamic acid (Pryo-Q), as disclosed in Liu et al. (J Pharm Sci. October 2019;108(10):3194-3200) https: / / pubmed.ncbi.nlm.nih.gov / 31145921 / and Nguyen et al. (Int. J. Mol. Sci. July 20, 2017;18(7):1575) https: / / www.researchgate.net / figure / Cyclization-reactions-of-N-terminal-glutamine-and-glutamate-residues-in-a-polypeptide_fig4_318926365.Additional information is provided on page 7 and in Table 4 of Xu et al. (MAbs, February / March 2019; 11(2):239-264), as well as in the following reference publications: (1) Yu et al., “Investigation of N-terminal glutamate cyclization of recombinant monoclonal antibody in formulation development”, J. Pharm. Biomed. Anal., 2006, 42, 455–463 and Dick et al., “Determination of the origin of the N-terminal pyro-glutamate variation in monoclonal antibodies using model peptides”, Biotechnol. Bioeng., 2007, 97, 544–553, the disclosures of which are incorporated herein by reference in their entirety.

[0153] In other embodiments, the antibody comprises the heavy and light chain CDRs or variable regions of ravulizumab. Thus, in one embodiment, the antibody comprises the CDR1, CDR2, and CDR3 domains of the VH region of ravulizumab having the sequences shown in SEQ ID NO:12, and the CDR1, CDR2, and CDR3 domains of the VL region of ravulizumab having the sequences shown in SEQ ID NO:8. In another embodiment, the antibody comprises heavy chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NO:19, 18, and 3, respectively, and light chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NO:4, 5, and 6, respectively. In another embodiment, the antibody comprises VH and VL regions having the amino acid sequences shown in SEQ ID NO:12 and SEQ ID NO:8, respectively.

[0154] Another exemplary anti-C5 antibody is the antibody BNJ421, which comprises heavy and light chains having the sequences shown in SEQ ID NO:20 and 11, respectively, or antigen-binding fragments and variants thereof. BNJ421 (also known as ALXN1211) is described in WO2015134894 and U.S. Patent No. 9,079,949, the entire teachings of which are incorporated herein by reference.

[0155] In other embodiments, the antibody comprises the heavy and light chain CDRs or variable regions of BNJ421. Thus, in one embodiment, the antibody comprises the CDR1, CDR2, and CDR3 domains of the VH region of BNJ421 having the sequence shown in SEQ ID NO: 12, and the CDR1, CDR2, and CDR3 domains of the VL region of BNJ421 having the sequence shown in SEQ ID NO: 8. In another embodiment, the antibody comprises heavy chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 19, 18, and 3, respectively, and light chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 4, 5, and 6, respectively. In another embodiment, the antibody comprises VH and VL regions having the amino acid sequences shown in SEQ ID NO: 12 and SEQ ID NO: 8, respectively.

[0156] The exact boundaries of the CDRs are defined differently according to different methods. In some embodiments, the positions of the CDRs or framework regions within the light or heavy chain variable domains are as defined by Kabat et al. [(1991) "Sequences of Proteins of Immunological Interest" NIH Publication No. 91-3242, Department of Health and Human Services, Bethesda, MD]. In such cases, the CDRs may be referred to as "Kabat CDRs" (e.g., "Kabat LCDR2" or "Kabat HCDR1"). In some embodiments, the positions of the CDRs of the light or heavy chain variable regions are as defined by Chothia et al. (Nature, 342:877-83, 1989). Thus, these regions may be referred to as "Chothia CDRs" (e.g., "Chothia LCDR2" or "Chothia HCDR3"). In some embodiments, the positions of the CDRs of the light and heavy chain variable regions may be defined by the Kabat-Chothia combined definition. In such embodiments, these regions may be referred to as "combined Kabat-Chothia CDRs". Thomas, C. et al. (Mol. Immunol., 33:1389-401, 1996) illustrated the identification of CDR boundaries according to the Kabat and Chothia numbering schemes.

[0157] Another exemplary anti-C5 antibody is the 7086 antibody described in U.S. Patent Nos. 8,241,628 and 8,883,158. In one embodiment, the antibody comprises the heavy and light chain CDRs or variable regions of the 7086 antibody (see U.S. Patent Nos. 8,241,628 and 8,883,158). In another embodiment, the antibody or antigen-binding fragment thereof comprises heavy chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 21, 22, and 23, respectively, and light chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 24, 25, and 26, respectively. In another embodiment, the antibody or antigen-binding fragment thereof comprises the VH region of the 7086 antibody having the sequence shown in SEQ ID NO: 27, and the VL region of the 7086 antibody having the sequence shown in SEQ ID NO: 28.

[0158] Another exemplary anti-C5 antibody is the 8110 antibody also described in U.S. Patent Nos. 8,241,628 and 8,883,158. In one embodiment, the antibody comprises the heavy and light chain CDRs or variable regions of the 8110 antibody. In another embodiment, the antibody or antigen-binding fragment thereof comprises heavy chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 29, 30, and 31, respectively, and light chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 32, 33, and 34, respectively. In another embodiment, the antibody comprises the VH region of the 8110 antibody having the sequence shown in SEQ ID NO: 35, and the VL region of the 8110 antibody having the sequence shown in SEQ ID NO: 36.

[0159] Another exemplary anti-C5 antibody is the 305LO5 antibody described in U.S. Patent No. 9,765,135. In one embodiment, the antibody comprises the heavy and light chain CDRs or variable regions of the 305LO5 antibody. In another embodiment, the antibody or antigen-binding fragment thereof comprises heavy chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 37, 38, and 39, respectively, and light chain CDR1, CDR2, and CDR3 domains having the sequences shown in SEQ ID NOs: 40, 41, and 42, respectively. In another embodiment, the antibody comprises the VH region of the 305LO5 antibody having the sequence shown in SEQ ID NO: 43, and the VL region of the 305LO5 antibody having the sequence shown in SEQ ID NO: 44.

[0160] Another exemplary anti-C5 antibody is the SKY59 antibody (Fukuzawa, T. et al., Sci. Rep., 7:1080, 2017). In one embodiment, the antibody comprises the heavy and light chain CDRs or variable regions of the SKY59 antibody. In another embodiment, the antibody or an antigen-binding fragment thereof comprises a heavy chain comprising SEQ ID NO:45 and a light chain comprising SEQ ID NO:46.

[0161] In some embodiments, the anti-C5 antibody comprises the heavy and light chain variable regions or the heavy and light chains of the REGN3918 antibody (see U.S. Patent No. 10,633,434). In some embodiments, the anti-C5 antibody or an antigen-binding fragment thereof comprises a heavy chain variable region sequence shown in SEQ ID NO:47 and a light chain variable region comprising the sequence shown in SEQ ID NO:48. In some embodiments, the anti-C5 antibody or an antigen-binding fragment thereof comprises a heavy chain sequence shown in SEQ ID NO:49 and a light chain sequence shown in SEQ ID NO:50.

[0162] In another embodiment, the anti-C5 antibody is a biosimilar of eculizumab For example, in one embodiment, the anti-C5 antibody is, for example, the ABP 959 antibody (a biosimilar of eculizumab manufactured by Amgen Inc., USA), (a biosimilar of eculizumab manufactured by Generium JNC, Russia), SB12 (a biosimilar of eculizumab manufactured by Samsung Bioepis, Incheon, Korea), ISU305 (a biosimilar of eculizumab from ISU Abxis, Korea), (a biosimilar of eculizumab from CinnaGen, Iran), BCD148 (a biosimilar of eculizumab from Biocad Medical, Quebec, Canada), teduglutide (manufactured by Novartis), ravulizumab (manufactured by Roche Pharmaceuticals), CAN106 (manufactured by North Sea Kangcheng Pharmaceutical Co., Ltd., China) or pazelimab (manufactured by Regeneron Pharmaceuticals).

[0163] In some embodiments, the anti-C5 antibody described herein comprises a heavy chain CDR1 that comprises or consists of the following amino acid sequence: GHIFSNYWIQ (SEQ ID NO:19). In some embodiments, the anti-C5 antibody described herein comprises a heavy chain CDR2 that comprises or consists of the following amino acid sequence: EILPGSGHTEYTENFKD (SEQ ID NO:18). In some embodiments, the anti-C5 antibody described herein comprises a heavy chain variable region comprising the following amino acid sequence:

[0164] QVQLVQSGAE VKKPGASVKV SCKASGHIFS NYWIQWVRQA PGQGLEWMGE ILPGSGHTEYTENFKDRVTM TRDTSTSTVY MELSSLRSED TAVYYCARYF FGSSPNWYFD VWGQGTLVTV SS(SEQ IDNO:12).

[0165] In some embodiments, the anti-C5 antibodies described herein comprise a light chain variable region comprising the following amino acid sequence:

[0166] DIQMTQSPSS LSASVGDRVT ITCGASENIY GALNWYQQKP GKAPKLLIYG ATNLADGVPSRFSGSGSGTD FTLTISSLQP EDFATYYCQN VLNTPLTFGQ GTKVEIK(SEQ ID NO:8).

[0167] In some embodiments, the anti-C5 antibodies described herein may comprise a variant human Fc constant region that binds to the human neonatal Fc receptor (FcRn) with a greater affinity than the native human Fc constant region from which the variant human Fc constant region is derived. For example, relative to the native human Fc constant region from which the variant human Fc constant region is derived, the Fc constant region may comprise one or more (e.g., two, three, four, five, six, seven, or eight or more) amino acid substitutions. The substitutions may increase the binding affinity of an IgG antibody containing the variant Fc constant region for FcRn at pH 6.0 while maintaining the pH-dependence of the interaction. Methods for testing whether one or more substitutions in the Fc constant region of an antibody increase the affinity of the Fc constant region for FcRn at pH 6.0 (while maintaining the pH-dependence of the interaction) are known in the art and are illustrated in the working examples. See, e.g., WO2015134894 and U.S. Patent No. 9,079,949, the disclosures of which are incorporated herein by reference in their entireties.

[0168] Substitutions that enhance the binding affinity of an antibody Fc constant region for FcRn are known in the art and include, for example, (1) the M252Y / S254T / T256E triple substitution (Dall’Acqua, W. et al., J. Biol. Chem., 281:23514-24, 2006); (2) the M428L or T250Q / M428L substitution (Hinton, P. et al., J. Biol. Chem., 279:(6213-6, 2004; Hinton, P. et al., J. Immunol., 176:346-56, 2006); and (3) N434A or T307 / E380A / N434A substitutions (Petkova, S. et al., Int. Immunol., 18:1759-69, 2006). Additional substitution pairs: P257I / Q311I, P257I / N434H, and D376V / N434H (Datta-Mannan, A. et al., J. Biol. Chem., 282:1709-17, 2007), the respective disclosures of which are incorporated herein by reference in their entirety.

[0169] In some embodiments, the variant constant region has a substitution to valine at EU amino acid position 255. In some embodiments, the variant constant region has a substitution to asparagine at EU amino acid position 309. In some embodiments, the variant constant region has a substitution to isoleucine at EU amino acid position 312. In some embodiments, the variant constant region has a substitution at EU amino acid position 386.

[0170] In some embodiments, the variant Fc constant region contains no more than 30 (e.g., no more than 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, or 2) amino acid substitutions, insertions, or deletions relative to the native constant region from which it is derived. In some embodiments, the variant Fc constant region contains one or more amino acid substitutions selected from the group consisting of: M252Y, S254T, T256E, N434S, M428L, V259I, T250I, and V308F. In some embodiments, the variant human Fc constant region contains methionine at position 428 and asparagine at position 434 of the native human IgG Fc constant region, each in EU numbering. In some embodiments, the variant Fc constant region contains the 428L / 434S double substitution as described, for example, in U.S. Patent No. 8,088,376.

[0171] In some embodiments, due to antibody engineering, the precise positions of these mutations can be shifted from the native human Fc constant region positions. For example, when used in an IgG2 / 4 chimeric Fc, the 428L / 434S double substitution can correspond to 429L and 435S in the M429L and N435S variants found in ravulizumab and described in U.S. Patent No. 9,079,949, the disclosure of which is incorporated herein by reference in its entirety.

[0172] In some embodiments, the variant constant region contains substitutions at amino acid positions 237, 238, 239, 248, 250, 252, 254, 255, 256, 257, 258, 265, 270, 286, 289, 297, 298, 303, 305, 307, 308, 309, 311, 312, 314, 315, 317, 325, 332, 334, 360, 376, 380, 382, 384, 385, 386, 387, 389, 424, 428, 433, 434 or 436 (EU numbering) relative to the native human Fc constant region. In some embodiments, the substitutions are selected from the group consisting of: methionine substituting for glycine at position 237; alanine substituting for proline at position 238; lysine substituting for serine at position 239; isoleucine substituting for lysine at position 248; alanine, phenylalanine, isoleucine, methionine, glutamine, serine, valine, tryptophan or tyrosine substituting for threonine at position 250; phenylalanine, tryptophan or tyrosine substituting for methionine at position 252; threonine substituting for serine at position 254; glutamate substituting for arginine at position 255; aspartate, glutamate or glutamine substituting for threonine at position 256; alanine, glycine, isoleucine, leucine, methionine, asparagine, serine, threonine or valine substituting for proline at position 257; histidine substituting for glutamate at position 258; alanine substituting for aspartate at position 265; phenylalanine substituting for aspartate at position 270; alanine or glutamate substituting for asparagine at position 286; histidine substituting for threonine at position 289; alanine substituting for asparagine at position 297; glycine substituting for serine at position 298; alanine substituting for valine at position 303; alanine substituting for valine at position 305; alanine, aspartate, phenylalanine, glycine, histidine, isoleucine, lysine, leucine, methionine, asparagine, proline, glutamine, arginine, serine, valine, tryptophan or tyrosine substituting for threonine at position 307; alanine, phenylalanine, isoleucine, leucine, methionine, proline, glutamine or threonine substituting for valine at position 308; alanine, aspartate, glutamate, proline or arginine substituting for leucine or valine at position 309; alanine, histidine or isoleucine substituting for glutamine at position 311; alanine or histidine substituting for aspartate at position 312; lysine or arginine substituting for leucine at position 314; alanine or histidine substituting for asparagine at position 315; alanine substituting for lysine at position 317; glycine substituting for asparagine at position 325; valine substituting for isoleucine at position 332; leucine substituting for lysine at position 334; histidine substituting for lysine at position 360;Aspartic acid at position 376 substituted with alanine; glutamic acid at position 380 substituted with alanine; glutamic acid at position 382 substituted with alanine; asparagine or serine at position 384 substituted with alanine; glycine at position 385 substituted with aspartic acid or histidine; glutamine at position 386 substituted with proline; proline at position 387 substituted with glutamic acid; asparagine at position 389 substituted with alanine or serine; serine at position 424 substituted with alanine; methionine at position 428 substituted with alanine, aspartic acid, phenylalanine, glycine, histidine, isoleucine, lysine, leucine, asparagine, proline, glutamine, serine, threonine, valine, tryptophan or tyrosine; histidine at position 433 substituted with lysine; asparagine at position 434 substituted with alanine, phenylalanine, histidine, serine, tryptophan or tyrosine; and tyrosine or phenylalanine at position 436 substituted with histidine, all in EU numbering;

[0173] In some embodiments, a suitable anti-C5 antibody for use in the methods described herein comprises a heavy chain polypeptide comprising the amino acid sequence shown in SEQ ID NO: 14 and / or a light chain polypeptide comprising the amino acid sequence shown in SEQ ID NO: 11. Alternatively, in some embodiments, the anti-C5 antibody for use in the methods described herein comprises a heavy chain polypeptide comprising the amino acid sequence shown in SEQ ID NO: 20 and / or a light chain polypeptide comprising the amino acid sequence shown in SEQ ID NO: 11.

[0174] In one embodiment, the antibody binds to C5 with an affinity dissociation constant (K D ) of at least 0.1 (e.g., at least 0.15, 0.175, 0.2, 0.25, 0.275, 0.3, 0.325, 0.35, 0.375, 0.4, 0.425, 0.45, 0.475, 0.5, 0.525, 0.55, 0.575, 0.6, 0.625, 0.65, 0.675, 0.7, 0.725, 0.75, 0.775, 0.8, 0.825, 0.85, 0.875, 0.9, 0.925, 0.95 or 0.975) nM at pH 7.4 and 25°C (and additionally under physiological conditions). In one embodiment, the antibody binds to C5 with an affinity dissociation constant (KD) of about 0.5 nM at pH 7.4 and 25°C (and additionally under physiological conditions). In some embodiments, the K D of the anti-C5 antibody or its antigen-binding fragment is not greater than 1 (e.g., not greater than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3 or 0.2) nM. In some embodiments, the antibody has a K of about 22 nM at pH 6.0 and 25°C (and additionally under physiological conditions)D Binds to C5.

[0175] In other embodiments, [(K of the antibody against C5 at pH 6.0 at 25°C D ) / (K of antibody against C5 at pH 7.4 at 25°C D )] greater than 21 (e.g., greater than 22, 23, 24, 25, 26, 27, 28, 29, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, 550 40, 250, 260, 270, 280, 290, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 6500, 7000, 7500 or 8000).

[0176] Methods for determining whether an antibody binds to a protein antigen and / or the affinity of an antibody for a protein antigen are known in the art. For example, the binding of an antibody to a protein antigen can be detected and / or quantified using a variety of techniques, such as, but not limited to, Western blot, dot blot, surface plasmon resonance (SPR) detection (e.g., BIAcore system; Pharmacia biosensor AB, Uppsala, Sweden and Piscataway, NJ) or enzyme-linked immunosorbent assay (ELISA; Benny KC Lo (2004) "Antibody Engineering: Methods and Protocols", Humana Press (ISBN: 1588290921); Johne, B. et al., J. Immunol. Meth., 160: 191-8, 1993; U. et al., Ann. Biol. Clin., 51:19-26, 1993; U. et al., Biotechniques, 11:620-7, 1991). In addition, methods for measuring affinity (e.g., dissociation and association constants) are described in the working examples.

[0177] As used herein, the term “k a ” refers to the rate constant for the association of an antibody with an antigen. The term “k d ” refers to the rate constant for the dissociation of an antibody from an antibody / antigen complex. The term “kD ” refers to the equilibrium dissociation constant of the antibody-antigen interaction. The equilibrium dissociation constant K is derived from the ratio of kinetic rate constants D = k a / k d . Such assays can be measured, for example, at 25 °C or 37 °C. The kinetics of antibody binding to human C5 can be determined, for example, at pH 8.0, 7.4, 7.0, 6.5, and 6.0 via SPR on a BIAcore 3000 instrument using an anti-Fc capture method to immobilize the antibody.

[0178] In one embodiment, the anti-C5 antibody or its antigen-binding fragment blocks the cleavage of C5 into C5a and C5b. By this blocking effect, for example, the pro-inflammatory effect of C5a on the cell surface and the formation of the C5b-9 membrane attack complex (MAC) are inhibited.

[0179] Methods for determining whether a particular antibody as described herein inhibits C5 cleavage are known in the art. Inhibition of human complement component C5 can reduce the complement-mediated cytolytic ability in the body fluid of a subject. It can be measured by methods known in the art, such as, for example, by a conventional hemolysis assay, such as the hemolysis assay (Kabat and Mayer (eds.), "Experimental Immunochemistry," 2nd ed., 135-240, Springfield, IL, CC Thomas (1961), pp. 135-139), or a conventional variant of this assay, such as the chicken erythrocyte hemolysis method (Hillmen, P. et al., N. Engl. J. Med., 350:552-9, 2004) to measure the reduction in this complement-mediated cytolytic ability present in body fluids. Methods for determining whether a candidate compound inhibits the cleavage of human C5 into C5a and C5b forms are known in the art (Evans, M. et al., Molecular Immunology, 32:1183-95, 1995). The concentration and / or biological activity of C5a and C5b in body fluids can be measured, for example, by methods known in the art. For C5b, a hemolysis assay or an assay for soluble C5b-9 as discussed herein can be used. Other assays known in the art can also be used. Using these or other suitable types of assays, candidate agents capable of inhibiting human complement component C5 can be screened.

[0180] Immunological techniques such as, but not limited to, ELISA can be used to measure the protein concentration of C5 and / or its cleavage products to determine the ability of an anti-C5 antibody or its antigen-binding fragment to inhibit the conversion of C5 into bioactive products. In some embodiments, C5a generation is measured. In some embodiments, C5b-9 neoepitope-specific antibodies are used to detect MAC formation.

[0181] Hemolysis assays can be used to determine the inhibitory activity of an anti-C5 antibody or an antigen-binding fragment thereof on complement activation. To assay the effect of an anti-C5 antibody or an antigen-binding fragment thereof on hemolysis mediated by the classical complement pathway in an in vitro serum test solution, for example, sheep red blood cells coated with hemolysin or chicken red blood cells sensitized with an anti-chicken red blood cell antibody are used as target cells. The percent lysis is normalized by considering 100% lysis to be equal to the lysis that occurs in the absence of an inhibitor. In some embodiments, the classical complement pathway is activated by human IgM antibody, such as, for example, as utilized in Classical Pathway Complement Kit ( COMPL CP310, Euro-Diagnostica, Sweden). Briefly, in the presence of human IgM antibody, the test serum is incubated with the anti-C5 antibody or an antigen-binding fragment thereof. The amount of C5b-9 produced is measured by contacting the mixture with an enzyme-conjugated anti-C5b-9 antibody and a fluorescent substrate and measuring the absorbance at an appropriate wavelength. As a control, the test serum is incubated in the absence of the anti-C5 antibody or an antigen-binding fragment thereof. In some embodiments, the test serum is C5-deficient serum reconstituted with C5 polypeptide.

[0182] To assay the effect of an anti-C5 antibody or an antigen-binding fragment thereof on hemolysis mediated by the alternative pathway, unsensitized rabbit or guinea pig red blood cells can be used as target cells. In some embodiments, the serum test solution is C5-deficient serum reconstituted with C5 polypeptide. The percent lysis is normalized by considering 100% lysis to be equal to the lysis that occurs in the absence of an inhibitor. In some embodiments, the complement alternative pathway is activated by a lipopolysaccharide molecule, such as, for example, as utilized in Alternative Pathway Complement Kit ( COMPL AP330, Euro-Diagnostica, Sweden). Briefly, in the presence of lipopolysaccharide, the test serum is incubated with the anti-C5 antibody or an antigen-binding fragment thereof. The amount of C5b-9 produced is measured by contacting the mixture with an enzyme-conjugated anti-C5b-9 antibody and a fluorescent substrate and measuring the fluorescence at an appropriate wavelength. As a control, the test serum is incubated in the absence of the anti-C5 antibody or an antigen-binding fragment thereof.

[0183] In some embodiments, CH50eq assay is used to quantify C5 activity or its inhibition. The CH50eq assay is a method for measuring total classical complement activity in serum. This test is a lysis assay that uses antibody-sensitized red blood cells as activators of the classical complement pathway and test sera at various dilutions to determine the amount required to produce 50% lysis (CH50). The percentage of hemolysis can be determined, for example, using a spectrophotometer. The CH50eq assay provides an indirect measure of terminal complement complex (TCC) formation because the TCC itself is directly responsible for the measured hemolysis. This assay is known and commonly practiced by those skilled in the art. Briefly, to activate the classical complement pathway, an undiluted serum sample (e.g., a reconstituted human serum sample) is added to a microtiter well containing antibody-sensitized red blood cells, thereby generating TCC. Subsequently, the activated serum is diluted in the microtiter well, and the microtiter well is coated with a capture reagent (e.g., an antibody that binds to one or more components of the TCC). The TCC present in the activated sample binds to the monoclonal antibody coating the surface of the microtiter well. The wells are washed and a detection reagent, which is detectably labeled and recognizes the bound TCC, is added to each well. The detectable label can be, for example, a fluorescent label or an enzyme label. The assay results are expressed as CH50 units equivalent per milliliter (CH50 U Eq / mL).

[0184] Inhibitions related to terminal complement activity, for example, include at least a 5 (e.g., at least 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60) % reduction in terminal complement activity in, for example, a hemolysis assay or a CH50eq assay, compared to the effect of a control antibody (or its antigen-binding fragment) under similar conditions and at equimolar concentrations. As used herein, substantially inhibit means inhibiting at least 40 (e.g., at least 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95 or higher) % of a given activity (e.g., terminal complement activity). In some embodiments, the anti-C5 antibodies described herein contain one or more amino acid substitutions relative to the CDRs of eculizumab (i.e., SEQ ID NO: 1-6), but retain at least 30 (e.g., at least 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95) % of the complement inhibitory activity of eculizumab in a hemolysis assay or a CH50eq assay.

[0185] The anti-C5 antibodies described herein have a serum half-life in humans of at least 20 (e.g., at least 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, or 55) days. In another embodiment, the anti-C5 antibodies described herein have a serum half-life in humans of at least 40 days. In another embodiment, the anti-C5 antibodies described herein have a serum half-life in humans of approximately 43 days. In another embodiment, the anti-C5 antibodies described herein have a serum half-life in humans between 39 and 48 days. Methods for measuring the serum half-life of an antibody are known in the art. In some embodiments, the anti-C5 antibody or antigen-binding fragment thereof has a serum half-life that is at least 20 (e.g., 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 250, 300, 400, or 500) % greater than that of eculizumab, as measured, for example, in one of the murine model systems described in the working examples (e.g., C5-deficient / NOD / scid mice or hFcRn transgenic mouse model systems).

[0186] In one embodiment, the antibody competes for binding and / or binds to the same epitope on C5 as the antibodies described herein. The term “binds to the same epitope” with respect to two or more antibodies means that the antibodies bind to the same segment of amino acid residues, as determined by a given method. Techniques for determining whether an antibody binds to the same epitope on C5 as the antibodies described herein include, for example, epitope mapping methods such as x-ray analysis of crystals of the antigen:antibody complex and hydrogen / deuterium exchange mass spectrometry (HDX-MS). Antibodies that are expected to bind to the same epitope have the same VH and VL or the same CDR1, CDR2, and CDR3 sequences.

[0187] An antibody that “competes for binding to a target” with another antibody is an antibody that inhibits (partially or completely) the binding of the other antibody to the target. Whether two antibodies compete with each other for binding to a target, i.e., whether one antibody inhibits the binding of the other antibody to the target and to what extent it inhibits the binding of the other antibody to the target, can be determined using known competition assays. In certain embodiments, the antibody competes with and inhibits the binding of another antibody to the target by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100%. The level of inhibition or competition can vary, depending on which antibody is the “blocking antibody” (i.e., the antibody that is incubated with the target first). The competing antibody can bind, for example, to the same epitope, an overlapping epitope, or an adjacent epitope (e.g., as demonstrated by steric hindrance).

[0188] The anti-C5 antibodies or antigen-binding fragments thereof described herein that are used in the methods described herein can be produced using a variety of techniques well known in the art. Monoclonal antibodies can be obtained by a variety of techniques familiar to those skilled in the art. Briefly, spleen cells from animals immunized with the desired antigen are typically immortalized by fusion with myeloma cells ( G. & Milstein, C., Eur. J. Immunol., 6:511-9, 1976)). Methods of immortalization include transformation with Epstein Barr Virus, oncogenes, or retroviruses or other methods known in the art. Colonies produced by individual immortalized cells are screened to produce antibodies having the desired specificity and affinity for the antigen, and the yield of monoclonal antibodies produced by these cells can be enhanced by a variety of techniques, including injection into the peritoneal cavity of a vertebrate host. Alternatively, DNA sequences encoding monoclonal antibodies or their binding fragments can be isolated by screening a DNA library from human B cells (Huse, W. et al., Science, 246:1275-81, 1989).

[0189] III. Compositions

[0190] The present invention also provides compositions comprising an anti-C5 antibody or an antigen-binding fragment thereof. In one embodiment, the composition comprises an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising the CDR1, CDR2, and CDR3 domains in the heavy chain variable region having the sequence shown in SEQ ID NO:12, and the CDR1, CDR2, and CDR3 domains in the light chain variable region having the sequence shown in SEQ ID NO:8. In another embodiment, the anti-C5 antibody comprises a heavy chain and a light chain having the sequences shown in SEQ ID NO:14 and 11, respectively. In another embodiment, the anti-C5 antibody comprises a heavy chain and a light chain having the sequences shown in SEQ ID NO:20 and 11, respectively.

[0191] These compositions can be formulated as pharmaceutical solutions, for example for administration to a subject according to any of the methods described herein. Pharmaceutical compositions generally comprise a pharmaceutically acceptable carrier. As used herein, "pharmaceutically acceptable carrier" means and includes any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and the like that are physiologically compatible. The composition can comprise pharmaceutically acceptable salts, e.g., acid addition salts or base addition salts, sugars, carbohydrates, polyols, and / or tonicity modifiers.

[0192] The composition can be formulated according to standard methods. Pharmaceutical formulations are established technology (see, e.g., Gennaro (2000) “Remington: The Science and Practice of Pharmacy”, 20th Edition, Lippincott, Williams & Wilkins (ISBN: 0683306472); Ansel et al. (1999) “Pharmaceutical Dosage Forms and Drug Delivery Systems”, 7th Edition, Lippincott Williams & Wilkins Publishers (ISBN: 0683305727); and Kibbe (2000) “Handbook of Pharmaceutical Excipients American Pharmaceutical Association”, Third Edition (ISBN: 091733096X)). In some embodiments, the composition can be formulated as, for example, a buffered solution at a suitable concentration and suitable for storage at 2°C - 8°C (e.g., 4°C). In some embodiments, the composition can be formulated for storage at a temperature below 0°C (e.g., -20°C or -80°C). In some embodiments, the composition can be formulated for storage at 2°C - 8°C (e.g., 4°C) for up to 2 years (e.g., 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months, 10 months, 11 months, 1 1 / 2 years or 2 years). Thus, in some embodiments, the compositions described herein are stable for at least 1 year when stored at 2°C - 8°C (e.g., 4°C).

[0193] A pharmaceutical composition can be in a variety of forms. These forms include, for example, liquid, semi-solid, and solid dosage forms, such as liquid solutions (e.g., injectable and infusible solutions), dispersions, or suspensions, tablets, pills, powders, liposomes, and suppositories. The preferred form depends in part on the intended mode of administration and therapeutic application. A composition containing a composition for systemic or local delivery can be, for example, in the form of an injectable or infusible solution. Thus, the composition can be formulated for administration by a parenteral mode (e.g., intravenous, subcutaneous, intraperitoneal, or intramuscular injection). As used herein, "parenteral administration", "parenterally administered", and other grammatically equivalent phrases refer to modes of administration other than enteral and topical administration, typically by injection, and include, but are not limited to, intravenous, intranasal, intraocular, transpulmonary, intramuscular, intraarterial, intrathecal, intracapsular, intraorbital, intracardiac, intradermal, intralung, intraperitoneal, intratracheal, subcutaneous, subepidermal, intraarticular, subcapsular, subarachnoid, intraspinal, epidural, intracerebral, intracranial, intracarotid, and intrasternal injection and infusion.

[0194] IV. Methods

[0195] Provided herein are methods for preparing a human patient for surgery (e.g., cardiac surgery using cardiopulmonary bypass (CPB)) in a particular subgroup (e.g., human patients with kidney disease, including chronic kidney disease (CKD)), methods for inhibiting terminal complement activation in a human patient, methods for treating a human patient with CKD prior to cardiac surgery using CPB, methods for preventing or reducing (e.g., minimizing) cardiac surgery-associated acute kidney injury (CSA-AKI) in a human patient with CKD, and methods for preventing or reducing (e.g., minimizing) one or more MAKEs in a human patient with CKD.

[0196] In one embodiment, the dose of the anti-C5 antibody or antigen-binding fragment thereof is based on the patient's body weight. For example, in one embodiment, a 2700 mg dose of the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight ≥30 kg to <40 kg. In another embodiment, a 3000 mg dose of the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight ≥40 kg to <60 kg. In another embodiment, a 3300 mg dose of the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight ≥60 kg to <100 kg. In another embodiment, a 3600 mg dose of the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight ≥100 kg. In certain embodiments, the dosing regimen is adjusted to provide an optimal desired response (e.g., an effective response).

[0197] In one aspect, a method of preparing a human patient (e.g., a human patient suffering from kidney disease, including CKD) for a surgical procedure (e.g., cardiac surgery using CPB) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgical procedure.

[0198] In another embodiment, a method of preparing a human patient (e.g., a human patient suffering from kidney disease, including CKD) for a surgical procedure (e.g., cardiac surgery using CPB) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or an antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgical procedure.

[0199] In another embodiment, a method of preparing a human patient with CKD for cardiac surgery using CPB is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or an antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgical procedure at the following doses:

[0200] e) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg;

[0201] f) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg;

[0202] g) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or

[0203] h) 3600 mg for patients with a body weight of ≥ 100 kg.

[0204] In another aspect, a method of inhibiting terminal complement activation in a human patient (e.g., a human patient suffering from kidney disease, including CKD) before a surgical procedure (e.g., cardiac surgery using CPB) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgical procedure.

[0205] In one embodiment, a method is provided for inhibiting terminal complement activation in a human patient (e.g., a human patient with kidney disease, including CKD) prior to surgery (e.g., cardiac surgery using CPB), wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery.

[0206] In another embodiment, a method is provided for inhibiting terminal complement activation in a human patient with CKD prior to cardiac surgery using CPB, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0207] a) 2700 mg for patients with a body weight ≥ 30 kg to < 40 kg;

[0208] b) 3000 mg for patients with a body weight ≥ 40 kg to < 60 kg;

[0209] c) 3300 mg for patients with a body weight ≥ 60 kg to < 100 kg; or

[0210] d) 3600 mg for patients with a body weight ≥ 100 kg.

[0211] In some embodiments, terminal complement activation is inhibited in a human patient according to the methods described herein, as evaluated by any suitable assay. In one embodiment, the method inhibits terminal complement activation in a human patient, e.g., inhibits by 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%.

[0212] In another aspect, a method is provided for treating a human patient with kidney disease (e.g., CKD) prior to cardiac surgery (e.g., cardiac surgery using CPB), wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery.

[0213] In one embodiment, a method of treating a human patient having a kidney disease (e.g., CKD) prior to cardiac surgery (e.g., cardiac surgery using CPB) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NOs: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NOs: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery.

[0214] In another embodiment, a method of treating a human patient having CKD prior to cardiac surgery using CPB is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NOs: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NOs: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0215] a) 2700 mg for patients with a body weight ≥ 30 kg to < 40 kg;

[0216] b) 3000 mg for patients with a body weight ≥ 40 kg to < 60 kg;

[0217] c) 3300 mg for patients with a body weight ≥ 60 kg to < 100 kg; or

[0218] d) 3600 mg for patients with a body weight ≥ 100 kg.

[0219] In another aspect, a method of preventing or reducing CSA-AKI in a human patient having a kidney disease (e.g., CKD) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, and wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before cardiac surgery (e.g., cardiac surgery using CPB).

[0220] In one embodiment, a method of preventing or reducing CSA-AKI in a human patient having a kidney disease (e.g., CKD) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before cardiac surgery (e.g., cardiac surgery using CPB).

[0221] In another embodiment, a method of preventing or reducing CSA-AKI in a human patient having CKD is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before cardiac surgery (e.g., cardiac surgery using CPB) at the following doses:

[0222] a) 2700 mg for patients with a body weight ≥ 30 kg to < 40 kg;

[0223] b) 3000 mg for patients with a body weight ≥ 40 kg to < 60 kg;

[0224] c) 3300 mg for patients with a body weight ≥ 60 kg to < 100 kg; or

[0225] d) 3600 mg for patients with a body weight ≥ 100 kg.

[0226] In another aspect, a method of preventing or reducing one or more MAKEs in a human patient having a kidney disease (e.g., CKD) is provided, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before cardiac surgery (e.g., cardiac surgery using CPB).

[0227] In one embodiment, provided is a method of preventing or reducing one or more MAKEs in a human patient having a kidney disease (e.g., CKD), wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before a cardiac surgery (e.g., a cardiac surgery using CPB).

[0228] In another embodiment, provided is a method of preventing or reducing one or more MAKEs in a human patient having CKD, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof comprises CDR1, CDR2, and CDR3 heavy chain sequences as set forth in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as set forth in SEQ ID NO: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before a cardiac surgery (e.g., a cardiac surgery using CPB) at the following doses:

[0229] a) 2700 mg for patients with a body weight ≥ 30 kg to < 40 kg;

[0230] b) 3000 mg for patients with a body weight ≥ 40 kg to < 60 kg;

[0231] c) 3300 mg for patients with a body weight ≥ 60 kg to < 100 kg; or

[0232] d) 3600 mg for patients with a body weight ≥ 100 kg.

[0233] In one embodiment, the anti-C5 antibody or an antigen-binding fragment thereof is administered to the patient at least one calendar day before the surgery (e.g., a cardiac surgery using CPB). In another embodiment, the anti-C5 antibody or an antigen-binding fragment thereof is administered one to seven calendar days before the surgery. For example, in one embodiment, the anti-C5 antibody or an antigen-binding fragment thereof is administered one, two, three, four, five, six, or seven calendar days before the surgery.

[0234] V. Results

[0235] In certain embodiments, the methods described herein provide optimal desired responses (e.g., inhibiting terminal complement activation in a human patient (e.g., a human patient with a kidney disease, including CKD) prior to surgery (e.g., cardiac surgery using CPB), preventing or reducing CSA-AKI in a human patient with a kidney disease (e.g., CKD) undergoing surgery (e.g., cardiac surgery using CPB), and / or preventing or reducing one or more MAKEs in a human patient with a kidney disease (e.g., CKD) undergoing surgery (e.g., cardiac surgery using CPB)).

[0236] In certain embodiments, the methods described herein are sufficient to maintain a specific serum trough concentration of an anti-C5 antibody or an antigen-binding fragment thereof. In one embodiment, for example, the method maintains the serum trough concentration of the anti-C5 antibody or an antigen-binding fragment thereof at 50 μg / mL, 55 μg / mL, 60 μg / mL, 65 μg / mL, 70 μg / mL, 75 μg / mL, 80 μg / mL, 85 μg / mL, 90 μg / mL, 95 μg / mL, 100 μg / mL, 105 μg / mL, 110 μg / mL, 115 μg / mL, 120 μg / mL, 125 μg / mL, 130 μg / mL, 135 μg / mL, 140 μg / mL, 145 μg / mL, 150 μg / mL, 155 μg / mL, 160 μg / mL, 165 μg / mL, 170 μg / mL, 175 μg / mL, 180 μg / mL, 185 μg / mL, 190 μg / mL, 200 μg / mL, 205 μg / mL, 210 μg / mL, 215 μg / mL, 220 μg / mL, 225 μg / mL, 230 μg / mL, 240 μg / mL, 245 μg / mL, 250 μg / mL, 255 μg / mL, 260 μg / mL, 265 μg / mL, 270 μg / mL, 280 μg / mL, 290 μg / mL, 300 μg / mL, 305 μg / mL, 310 μg / mL, 315 μg / mL, 320 μg / mL, 325 μg / mL, 330 μg / mL, 335 μg / mL, 340 μg / mL, 345 μg / mL, 350 μg / mL, 355 μg / mL, 360 μg / mL, 365 μg / mL, 370 μg / mL, 375 μg / mL, 380 μg / mL, 385 μg / mL, 390 μg / mL, 395 μg / mL, 400 μg / mL, 405 μg / mL, 410 μg / mL, 415 μg / mL, 420 μg / mL, 425 μg / mL, 430 μg / mL, 435 μg / mL, 440 μg / mL, 445 μg / mL, 450 μg / mL, 455 μg / mL, 460 μg / mL, 465 μg / mL, 470 μg / mL, 475 μg / mL, 480 μg / mL, 485 μg / mL, 490 μg / mL, 495 μg / mL, 500 μg / mL, 505 μg / mL, 510 μg / mL, 515 μg / mL, 520 μg / mL, 525 μg / mL, 530 μg / mL, 535 μg / mL, 540 μg / mL, 545 μg / mL, 550 μg / mL, 555 μg / mL, 560 μg / mL, 565 μg / mL, 570 μg / mL, 575 μg / mL, 580 μg / mL, 585 μg / mL,590 μg / mL, 595 μg / mL, 600 μg / mL, 605 μg / mL, 610 μg / mL, 615 μg / mL, 620 μg / mL, 625 μg / mL, 630 μg / mL, 635 μg / mL, 640 μg / mL, 645 μg / mL, 650 μg / mL, 655 μg / mL, 660 μg / mL, 665 μg / mL, 670 μg / mL, 675 μg / mL, 680 μg / mL, 685 μg / mL, 690 μg / mL, 695 μg / mL, 700 μg / mL or greater. In one embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment at 100 μg / mL or greater, 150 μg / mL or greater, 200 μg / mL or greater, 250 μg / mL or greater, 300 μg / mL or greater, 350 μg / mL or greater, 400 μg / mL or greater, or 450 μg / mL or greater. In another embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment between 100 μg / mL and 700 μg / mL, preferably between 300 μg / mL and 600 μg / mL. In another embodiment, the method maintains the trough serum concentration of the anti-C5 antibody or its antigen-binding fragment at approximately 475 μg / mL. In another embodiment, the method maintains the peak serum concentration of the anti-C5 antibody or its antigen-binding fragment at less than approximately 1800 μg / mL, 1780 μg / mL, 1760 μg / mL, 1740 μg / mL, 1720 μg / mL, 1700 μg / mL, 1680 μg / mL, 1660 μg / mL, 1640 μg / mL, 1620 μg / mL, 1600 μg / mL, 1580 μg / mL, 1560 μg / mL, 1540 μg / mL, 1520 μg / mL, 1500 μg / mL, 1480 μg / mL, 1460 μg / mL, 1440 μg / mL, 1420 μg / mL, 1400 μg / mL, 1380 μg / mL, 1360 μg / mL, 1340 μg / mL, 1320 μg / mL, 1300 μg / mL, 1280 μg / mL, 1260 μg / mL, 1240 μg / mL, 1220 μg / mL, 1200 μg / mL, 1180 μg / mL, 1160 μg / mL, 1140 μg / mL, 1120 μg / mL, 1100 μg / mL, 1080 μg / mL, 1060 μg / mL, 1040 μg / mL, 1020 μg / mL, 1000 μg / mL, 980 μg / mL, 960 μg / mL, 940 μg / mL,920 μg / mL or 900 μg / mL or less. In other embodiments, the method maintains the peak serum concentration of the anti-C5 antibody or antigen-binding fragment thereof between 900 μg / mL and 1800 μg / mL, preferably between 1050 μg / mL and 1550 μg / mL. In another embodiment, the method maintains a peak serum concentration of the anti-C5 antibody or antigen-binding fragment thereof of about 1350 μg / mL.,

[0237] In another embodiment, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains at least 50 μg, 55 μg, 60 μg, 65 μg, 70 μg, 75 μg, 80 μg, 85 μg, 90 μg, 95 μg, 100 μg, 105 μg, 110 μg, 115 μg, 120 μg, 125 μg, 130 μg, 135 μg, 140 μg, 145 μg, 150 μg, 155 μg, 160 μg, 165 μg, 170 μg, 175 μg, 180 μg, 185 μg, 190 μg, 195 μg, 200 μg, 205 μg, 210 μg, 215 μg, 220 μg, 225 μg, 230 μg, 235 μg, 240 μg, 245 μg, 250 μg, 255 μg, 260 μg, 270 μg, 280 μg, 290 μg, 300 μg, 320 μg, 340 μg, 360 μg, 380 μg, 400 μg, 420 μg, 440 μg, 460 μg, 480 μg, 500 μg, 550 μg, 600 μg, 650 μg, 700 μg, 750 μg, 800 μg, 850 μg, 900 μg, 950 μg, 1000 μg, 1050 μg, 1100 μg, 1150 μg, 1200 μg, 1250 μg, 1300 μg, 1350 μg, 1400 μg, 1450 μg, 1500 μg, 1550 μg, 1600 μg, 1650 μg, 1700 μg, 1750 μg or more such as 1800 μg of antibody.

[0238] In another embodiment, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains the lowest free C5 concentration. In one embodiment, for example, the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient in an amount and frequency that maintains a free C5 concentration of 0.5 μg / mL or lower (e.g., 0.4 μg / mL, 0.3 μg / mL, 0.2 μg / mL or 0.1 μg / mL or lower).

[0239] The efficacy of the methods provided herein can be evaluated using any suitable means. In one embodiment, a single preoperative weight-based dose of the anti-C5 antibody or antigen-binding fragment thereof results in complete C5 inhibition for at least 18 days.

[0240] In one embodiment, the method inhibits terminal complement activation in a human patient, as assessed by any suitable assay. In one embodiment, the method inhibits terminal complement activation in a human patient, for example, inhibits by 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100%.

[0241] In another embodiment, the methods described herein prevent the need for renal replacement therapy (KRT).

[0242] In another embodiment, the method prevents or reduces CSA-AKI in a human patient with CKD. In one embodiment, CSA-AKI is characterized by an increase in the following:

[0243] a) Serum creatinine (sCr) or serum cystatin C (sCysC) ≥ 0.3 mg / dL within a 48-hour period within 7 days after CPB, and / or

[0244] b) sCr or sCysC ≥ 1.5 times baseline within 7 days after CPB or on days 15, 30, 60 or 90 after CPB.

[0245] In another embodiment, based on the highest sCr observed within 7, 30, 45, 60 or 90 days after CPB, the human patient does not have severe CSA-AKI (stage 2 or 3), as assessed by the improved Kidney Disease: Improving Global Outcomes (KDIGO) criteria, as shown in Table 1 of the Examples (see also KDIGO., Kidney Inter. Suppl. 2013; 3:1-150 and Khwaja A., Nephron. Clin. Pract. 2012; 120(4):c179-184).

[0246] In another embodiment, based on the highest sCr observed within 7, 30, 45, 60, or 90 days after CPB, the human patient does not have severe CSA-AKI, as evaluated by the modified "Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease" (RIFLE) criteria, as shown in Table 2 of the Examples (see also Bellomo R et al., Acute Dialysis Quality Initiative workgroup. Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group. Crit Care. 2004;8(4):R204 - R212).

[0247] In another embodiment, the method results in an improvement in the staging of kidney function after CSA-AKI, as shown in Table 3 of the Examples (see also Chawla LS et al., Acute kidney disease and renal recovery: consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup. Nat Rev Nephrol. 2017;13(4):241 - 257).

[0248] In another embodiment, the method results in stabilization of CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, characterized by sCr ≥ 2.0 - < 3.0 × baseline.

[0249] In another embodiment, the method results in improvement from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the improvement is characterized by sCr ≥ 1.5 - < 2.0 × baseline.

[0250] In another embodiment, the method results in partial recovery from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the partial recovery is characterized by sCr ≥ 1.1 - < 1.5 × baseline.

[0251] In another embodiment, the method results in complete recovery from CSA-AKI within 7, 30, 45, 60, or 90 days after surgery, where the complete recovery is characterized by sCr < 1.1 × baseline.

[0252] In another embodiment, the method prevents or reduces one or more MAKEs in a human patient with CKD. In one embodiment, one or more MAKEs are sustained kidney dysfunction (SKD), which is defined as, for example, an estimated glomerular filtration rate (eGFR) that is >25% lower than baseline after CPB, where the decrease in eGFR is determined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula based on serum cystatin C (sCysC) or serum creatinine (sCr). In another embodiment, one or more MAKEs are the occurrence of kidney replacement therapy (KRT) after CPB. In another embodiment, one or more MAKEs are death from any cause after CPB.

[0253] In another embodiment, the method results in a change in quality of life from baseline as evaluated via quality of life assessment. For example, in one embodiment, the quality of life assessment is the Kidney Disease Quality of Life Short Form (KDQOL-36 TM ). KDQOL-36 TM is a 36-item kidney-specific health-related quality of life measure that includes the 12-item Short Form Health Survey (SF-12) as a general core plus the burden of kidney disease, symptoms / problems of kidney disease, and the Kidney Disease Impact Scale.

[0254] In another embodiment, the quality of life assessment is the 5-dimension 5-level (EQ-5D-5L) of the EuroQol Group. The EQ-5D-5L is a standardized tool for self-assessment of health-related quality of life and has been used in a wide range of health conditions. The EQ 5D 5L includes 5 dimensions, each dimension describing a different aspect of health: mobility, self-care, usual activities, pain / discomfort, and anxiety / depression.

[0255] In another embodiment, the quality of life assessment is the Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue Scale. The FACIT scale is a 13-item questionnaire that assesses self-reported fatigue and its impact on daily activities and function over the previous 7 days.

[0256] In another embodiment, the method results in the shift of biomarkers associated with vascular inflammation (e.g., soluble tumor necrosis factor receptor 1 [TNF-R1]) to normal levels. In another embodiment, the method results in the shift of biomarkers associated with endothelial injury and / or activation (e.g., thrombomodulin) to normal levels. In another embodiment, the method results in the shift of biomarkers associated with kidney injury (e.g., neutrophil gelatinase-associated lipocalin [NGAL]) to normal levels. In another embodiment, the method results in the shift of biomarkers associated with inducers of cell cycle arrest (e.g., tissue inhibitor of metalloproteinase-2 [TIMP-2]) to normal levels. In another embodiment, the method results in the shift of complement proteins and complement activation pathway products (e.g., soluble C5b-9) to normal levels.

[0257] VI. Kits and Unit Dosages

[0258] Also provided herein are kits that include a therapeutically effective amount of a pharmaceutical composition suitable for use in the foregoing method, the pharmaceutical composition containing an anti-C5 antibody or an antigen-binding fragment thereof such as ravulizumab and a pharmaceutically acceptable carrier. The kit may optionally further include instructions, such as an administration schedule, to allow a physician (e.g., doctor, nurse, or patient) to administer the composition contained therein to a patient. The kit may also include a syringe.

[0259] Optionally, the kit includes multiple packages of single-dose pharmaceutical compositions, each package containing an effective amount of the anti-C5 antibody or an antigen-binding fragment thereof for a single administration according to the methods provided above. Instruments or devices necessary for administering the pharmaceutical composition may also be included in the kit. For example, the kit may provide one or more pre-filled syringes containing a certain amount of the anti-C5 antibody or an antigen-binding fragment thereof.

[0260] In one embodiment, the kit includes: (a) a dose of an anti-C5 antibody or an antigen-binding fragment thereof, having CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, and (b) instructions for using the anti-C5 antibody or an antigen-binding fragment thereof in any of the methods described herein.

[0261] VI. Uses

[0262] In another aspect, provided is an anti-C5 antibody or an antigen-binding fragment thereof (e.g., ravulizumab ), which is used to prepare a human patient with CKD for cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0263] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0264] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0265] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0266] d) 3600 mg for patients weighing ≥ 100 kg.

[0267] In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is provided, which is used to inhibit terminal complement activation in a human patient with CKD before cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0268] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0269] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0270] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0271] d) 3600 mg for patients weighing ≥ 100 kg.

[0272] In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is provided, which is used to treat a human patient with CKD before cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0273] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0274] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0275] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0276] d) 3600 mg for patients weighing ≥ 100 kg.

[0277] In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is provided for preventing or reducing CSA-AKI in human patients with CKD, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0278] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0279] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0280] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0281] d) 3600 mg for patients weighing ≥ 100 kg.

[0282] In another embodiment, an anti-C5 antibody or antigen-binding fragment thereof is provided for preventing or reducing one or more MAKEs in human patients with CKD, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0283] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0284] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0285] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0286] d) 3600 mg for patients weighing ≥ 100 kg.

[0287] In another aspect, the present invention provides the use of an anti-C5 antibody or antigen-binding fragment thereof (e.g., ravulizumab ) for preparing a human patient with CKD for cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before surgery at the following doses:

[0288] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0289] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0290] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0291] d) 3600 mg for patients weighing ≥ 100 kg.

[0292] In one embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for inhibiting terminal complement activation in a human patient with CKD prior to cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0293] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0294] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0295] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0296] d) 3600 mg for patients weighing ≥ 100 kg.

[0297] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for treating a human patient with CKD prior to cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0298] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0299] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0300] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0301] d) 3600 mg for patients weighing ≥ 100 kg.

[0302] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing CSA-AKI in a human patient with CKD, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgery at the following doses:

[0303] a) 2700 mg for patients weighing ≥ 30 kg to < 40 kg;

[0304] b) 3000 mg for patients weighing ≥ 40 kg to < 60 kg;

[0305] c) 3300 mg for patients weighing ≥ 60 kg to < 100 kg; or

[0306] d) 3600 mg for patients weighing ≥ 100 kg.

[0307] In another embodiment, there is provided the use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing one or more MAKEs in a human patient suffering from chronic kidney disease, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once pre-operatively at the following doses:

[0308] a) 2700 mg for patients with a body weight ≥ 30 kg to < 40 kg;

[0309] b) 3000 mg for patients with a body weight ≥ 40 kg to < 60 kg;

[0310] c) 3300 mg for patients with a body weight ≥ 60 kg to < 100 kg; or

[0311] d) 3600 mg for patients with a body weight ≥ 100 kg.

[0312] The following examples are illustrative only and should not be construed as limiting the scope of the disclosure in any way, as many variations and equivalents will become apparent to those skilled in the art after reading the disclosure. The content of all references, Genbank entries, patents, and published patent applications cited throughout this application are hereby expressly incorporated by reference.

[0313] Examples

[0314] Example: Ravulizumab for Protecting Patients with Chronic Kidney Disease (CKD) from Cardiac Surgery-Associated Kidney Injury (CSA-AKI) and / or Subsequent Major Adverse Kidney Events (MAKE) Phase 3 Study 1. Study Design

[0315] Patients with CKD undergoing cardiac surgery using CPB are at high risk of CSA-AKI. While CSA-AKI occurs in 20%-25% of patients in the general population undergoing cardiac surgery using CPB, it occurs in 60%-80% of patients in the context of CKD, and MAKE occurs in 20%-30% of patients. Inhibiting terminal complement injury to the kidney and vasculature can reduce the incidence, severity, and duration of postoperative CSA-AKI and reduce subsequent MAKE, thereby improving long-term survival and freedom from kidney replacement therapy (KRT), and reducing the progression of CKD.

[0316] Therefore, a randomized, placebo-controlled, double-blind study design was conducted to minimize bias and balance the effects of confounding factors in this complex and highly comorbid population. Throughout the study, participants in both treatment groups received standard of care as background therapy.

[0317] Figure 1

[0318] This is a phase 3, randomized, double-blind, placebo-controlled, multicenter study of ravulizumab in adult participants with CKD and stable heart disease who undergo non-emergency sternotomy with CPB for coronary artery bypass grafting (CABG), valve replacement or repair, or combined procedures, to reduce the risk of postoperative AKI and subsequent MAKE at 90 days after surgery (MAKE90). A schematic diagram of the trial design is shown in Figures 2A to 2G Participants considered at risk of AKI after CPB had an eGFR ≥20 to <60 mL / min / 1.73 m2 and a minimum Society of Thoracic Surgeons (STS) calculator renal failure risk score of 3%.

[0319] The study consisted of a screening period of up to 28 days during which randomization and dosing occurred 1 day to 7 days before the CPB procedure used, a primary evaluation period of 90 days after CPB, and a survival follow-up period of 365 days after CPB.

[0320] Approximately 736 participants were randomly assigned in a 1:1 ratio to treatment with ravulizumab or placebo. Randomization was stratified by baseline CKD stage (3A, 3B, 4) and type of surgery (mitral valve replacement or combined procedure versus other single procedures).

[0321] Eligible participants were randomized and received a single weight-based dose of ravulizumab or placebo. Randomization and dosing occurred on the same day, unless the day before dosing was required for preparation of the study intervention. Dosing had to occur at least 1 day before surgery, and surgery had to occur within 1 day to 7 days after dosing. The dosing date for each participant was Day 1. During the primary evaluation period, all treated participants were followed for 90 days after the CPB procedure, and survival follow-up was completed at 365 days after CPB. The total study duration was up to approximately 400 days. If a participant had completed the primary evaluation period, he / she was considered to have completed the study.

[0322] Analysis of the primary evaluation period was conducted when all participants had completed that period. In addition, two interim analyses of the study were conducted after approximately 30% and 50% of the randomized participants had completed the primary evaluation period, respectively, with the aim of assessing early futility in the first interim analysis and the need for sample size adjustment in the second interim analysis.

[0323] The end of the study was defined as the date on which the last participant completed the last visit as indicated in the activity schedule (see Objectives, Estimates, and Endpoints ).

[0324] This is a parallel-group treatment study with 2 groups, in which participants and researchers are blinded. Ravulizumab is being evaluated for reducing the risk of death, the need for KRT, and the continued decline in renal function in adult patients with CKD undergoing CPB for CABG, valve replacement or repair, or combined procedures.

[0325] Randomized participants receive a single weight-based dose of ravulizumab or placebo between 1 day and 7 days before the CPB procedure (i.e., up to 1 day before surgery at the latest).

[0326] 2. 3. MAKE and CSA-AKI

[0327] The primary objective of this study is to evaluate the efficacy of ravulizumab in reducing the risk of MAKE90 after CPB. The primary estimates include:

[0328] (1) Treatment: Ravulizumab or placebo;

[0329] (2) Population: Adult participants with CKD;

[0330] (3) Endpoint / variable: MAKE (MAKE90) at day 90 after CPB, which is defined as meeting at least 1 of the following criteria: eGFR (CKD-EPI formula using sCysC) decreased by ≥25% from baseline at day 90 after CPB, or initiation of KRT by day 90 after CPB, or death for any reason by day 90 after CPB;

[0331] (4) Incident events (IE): IE1: Exposure to iodinated contrast agent after administration of treatment by day 90 after CPB; IE2: Surgery without using CPB or surgery without using CPB within 15 days after administration of treatment; and IE3: Use of confounding interventions before surgery or use of interventions not permitted after administration of treatment by day 90 after CPB. Treatment policy strategy: Analyze the collected endpoints without considering IE; and

[0332] (5) Aggregate measure: The difference in the proportion of participants experiencing MAKE at 90 days after CPB between treatment groups, regardless of any IE.

[0333] The key secondary efficacy objectives of the study were to evaluate the efficacy of ravulizumab in reducing the risk of AKI (based on sCr) after CPB as follows: (1) no CSA-AKI on day 90 after CPB, (2) no severe CSA-AKI (KDIGO stage 2 or 3) based on the highest sCr observed within 7 days after CPB; (3) no any severe AKI (RIFLE injury or failure criteria) based on the highest sCr observed within 30 days after CPB; (4) no any severe AKI (KDIGO stage 2 or 3) based on the highest sCr observed within 30 days after CPB; (5) no any RIFLE failure criteria based on the highest sCr observed within 30 days after CPB; and (6) all-cause mortality from randomization to day 90 after CPB.

[0334] Another secondary efficacy objective was to evaluate the efficacy of ravulizumab in reducing the risk of MAKE (based on sCysC), MAKE (based on sCr), AKI (based on sCr), and related outcomes after CPB. The corresponding endpoints and / or estimates included:

[0335] (1) MAKE and its components on days 30, 60, and 90 after CPB (except MAKE90 based on sCysC), occurrence of KRT or death on days 30, 60, and 90 after CPB, (2) the highest CSA-AKI stage within 3 and 7 days after CPB, (3) no CSA-AKI on days 15, 30, and 60 after CPB, (4) no any AKI on days 3, 7, 15, 30, 60, and 90 after CPB, and (5) for those patients who experienced CSA-AKI within 7 days after CPB, the progression of AKI on days 15, 30, 60, and 90 after CPB: complete recovery, partial recovery, improvement, stability, or deterioration.

[0336] The Healthcare Resource Utilization objective was to evaluate the impact of ravulizumab on healthcare resource utilization in participants with CKD undergoing non-emergency CPB, as assessed by: (1) the length of index hospital and ICU stays, (2) the number of days without mechanical ventilation by days 30 and 90 after CPB, (3) the readmission rate (all-cause or AKI-related) by days 30 and 90 after CPB, and (4) the number of days of KRT by days 30 and 90 after CPB.

[0337] The health-related QoL objective was to evaluate the impact of ravulizumab on the quality of life of participants with CKD undergoing non-emergency CPB, for example, as assessed by: (1) KDQOL-36 on days 30, 60, and 90 after CPB TMChanges from baseline, (2) changes in EQ-5D-5L from baseline at 30, 60, and 90 days after CPB, and (3) changes in FACIT-Fatigue from baseline at 30, 60, and 90 days after CPB.

[0338] Another objective is to evaluate the PK and PD of ravulizumab in participants with CKD undergoing non-emergency CPB, for example, via the serum concentration and absolute value of ravulizumab, changes from baseline, and percentage change in serum-free C5 concentration from baseline.

[0339] Another objective is to evaluate the safety of ravulizumab IV in participants with CKD undergoing non-emergency CPB, for example, via the incidence of TEAE and TESAE and changes in laboratory parameters from baseline at scheduled visits.

[0340] Another objective is to evaluate the immunogenicity of ravulizumab IV in participants with CKD undergoing non-emergency CPB, for example, via the incidence of ADA, ADA response category, and titer at 90 days after CPB.

[0341] The exploratory objective is to evaluate biomarkers at baseline and changes in response to treatment, for example, via biomarker assessments that may include, but are not limited to, complement pathway activation (e.g., plasma and urine soluble C5b-9), kidney injury (e.g., urine neutrophil gelatinase-associated lipocalin [NGAL]), and endothelial injury (e.g., plasma thrombomodulin [TM]).

[0342] The definitive objective is the efficacy in reducing the risk of sCysC-based CSA-AKI, for example, via AKI within 7 days of sCysC-based CPB: the highest AKI stage according to KDIGO criteria and no severe AKI (KDIGO stage 2 or 3).

[0343] Use the endpoint definitions shown in Table 1 in the study.

[0344] Table 1: Endpoint Definitions

[0345]

[0346] Table 1: Endpoint Definitions

[0347]

[0348] Abbreviations: AKI = acute kidney injury; CKD-EPI = Chronic Kidney Disease Epidemiology Collaboration; CPB = cardiopulmonary bypass; CSA-

[0349] AKI = Acute kidney injury related to cardiac surgery; eGFR = Estimated glomerular filtration rate; KDIGO = Kidney Disease: Improving Global Outcomes; KRT = Kidney replacement therapy; MAKE = Major adverse kidney event; RIFLE = Risk, Injury, Failure, Loss of kidney function, and End - stage kidney disease; sCr = Serum creatinine; sCysC = Serum cystatin C

[0350] The primary estimator of the study used a treatment - policy strategy based on the intention - to - treat analysis set to estimate treatment effects, regardless of any incident events (IE) and participant compliance with IP administration. This estimator was designed to provide a population - level estimate of the treatment effect on the binary endpoint MAKE90 after CPB in CKD patients who met the study eligibility criteria and were randomized into the study. The primary estimator included the following four attributes:

[0351] A. Population: Adult participants with CKD as defined by the inclusion and exclusion criteria

[0352] B. Variable: MAKE at day 90 after CPB (MAKE90)

[0353] C. Incident events (IE):

[0354] IE1: Exposure to iodinated contrast agents after treatment administration by day 90 after CPB

[0355] IE2: Surgery without the use of CPB or surgery without CPB within 15 days after treatment administration

[0356] IE3: Use of pre - operative confounding interventions or interventions not allowed after treatment administration by day 90 after CPB Note: Treatment - policy strategy: Analyze the collected endpoints without considering IE.

[0357] D. Aggregate measure: The difference in the proportion of participants experiencing MAKE at 90 days after CPB between treatment groups, regardless of the presence of IE.

[0358] Key secondary estimators were designed to provide population - level estimates of treatment effects on five binary endpoints, regardless of any IE. Each key secondary estimator would target the same estimates as the primary endpoint, as follows:

[0359] A. Population: Adult participants with CKD as defined by the inclusion and exclusion criteria

[0360] B. Variable:

[0361] No CSA - AKI at day 90 after CPB;

[0362] No severe CSA - AKI based on the highest sCr observed within 7 days after CPB

[0363] (Kidney Disease: Improving Global Outcomes [KDIGO] stage 2 or 3)

[0364] No severe AKI based on the highest sCr observed within 30 days after CPB

[0365] (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease [RIFLE] injury or failure criteria);

[0366] No severe AKI based on the highest sCr observed within 30 days after CPB

[0367] (KDIGO stage 2 or 3);

[0368] No RIFLE failure criteria based on the highest sCr observed within 30 days after CPB;

[0369] All-cause mortality from randomization to day 90 after CPB

[0370] C. Concurrent events (IE):

[0371] IE1: Exposure to iodinated contrast agent after administration of treatment up to day 90 after CPB;

[0372] IE2: Surgery without the use of CPB or surgery without the use of CPB within 15 days after administration of treatment;

[0373] IE3: Use of confounding interventions before surgery or use of interventions not allowed after administration of treatment up to day 90 after CP

[0374] Treatment guideline strategy: Analyze the collected endpoints without considering IE.

[0375] Pooled measurement: Difference in the proportion of participants experiencing key secondary endpoint events between treatment groups.

[0376] Table 2: Acute Kidney Injury (AKI) Staging According to the Modified KDIGO Criteria

[0377] The primary outcome measure (MAKE) was conceived to capture clinical outcomes after AKI and is defined as mortality, need for KRT, and SKD, which is defined as an estimated glomerular filtration rate (eGFR) by the CKD-EPI formula that is >25% lower than baseline (see, e.g., Billings FT et al., Nephron.Clin.Pract. 2014;127(1-4):89-93; Haverich A et al., Ann.Thorac.Surg. 2006;82(2):486-492; Levey AS et al., Ann.Intern.Med. 2009;150(9):604-612; and Palevsky PM et al., Clin.J.Am.Soc.Nephrol. 2012;7(5):844-850). SKD occurs due to nonrecovery from AKI and represents persistent worsening of CKD at 90 days. When compared to those patients without AKI or who recover from AKI, SKD is associated with multiple-fold higher risks of long-term death and progression to ESKD (see, e.g., Ishani A et al., J.Am.Soc.Nephrol. 2009;20(1):223-228; Wu VC et al., Kidney Int. 2011;80(11):1222-1230; and Cho JS et al., J.Thorac.Cardiovasc.Surg. 2021;161(2):681-8).

[0378] Skeletal muscle atrophy is widely recognized as a complication after cardiac surgery (van Venrooij LM et al., Nutrition (Burbank, Los Angeles County, Calif). 2012;28(1):40-45) and can confound sCr-based assessment of eGFR. As recommended for such cases in the KDIGO guidelines (KDIGO, 2013), sCysC is used to calculate SKD in the MAKE endpoint. Data from observational and randomized controlled intervention trials reporting AKI and MAKE outcomes after cardiopulmonary bypass were used to inform the MAKE 90 placebo rate assumption of 25%.

[0379] The occurrence of postoperative CSA-AKI is defined as the presence of one of the following observations during the 7 days after surgery using CPB, based on the modified KDIGO criteria: (1) an increase in sCr of ≥0.3 mg / dL within a 48-hour period, or (2) an increase in sCr to ≥1.5-fold baseline within 7 days after CPB.

[0380] As defined in Table 2, the highest AKI stage according to the modified KDIGO criteria that occurred within 3 and 7 days after surgery using CPB was determined (see also KDIGO., Kidney Inter. Suppl. 2013; 3:1 - 150 and Khwaja A., Nephron. Clin. Pract. 2012; 120(4):c179 - 184). Additionally, this staging was used to assess AKI at any time within 30 days after CPB based on the highest observed sCr; and to assess AKI at days 15, 30, 60, and 90 after CPB. Although the KDIGO criteria are widely adopted, in some cases (e.g., STS renal failure risk calculator), the RIFLE criteria are more familiar (e.g., O'Brien SM et al., Ann Thorac Surg. 2018; 105(5):1419 - 1428). Therefore, based on the highest observed sCr, the AKI stage according to the modified RIFLE criteria was assessed for AKI at any time within 30 days after CPB, and the staging criteria are outlined in Table 3 (see also Bellomo R et al., Acute Dialysis Quality Initiative workgroup. Acute renal failure - definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group. Crit Care. 2004; 8(4):R204 - R212). In the case of AKI, the reliable interpretation of changes in sCysC was exploratory in this study because it is yet to be defined and is not often used to define or stage AKI at this time.

[0381] Table 3: AKI Staging According to the Modified RIFLE Criteria

[0382]

[0383]

[0384] Table 4: Staging of Renal Function after CSA-AKI for Determining AKI Progression after Surgery (e.g., on Days 15 to 90)

[0385]

[0386] Changes in AKI progression after the highest CSA-AKI stage observed in the first 7 days after CPB were evaluated from day 15 to day 90 after CPB (based on sCr or need for KRT) to characterize AKI progression (recovery, improvement, stability, or deterioration). Stages of AKI progression after are defined in Table 4 (see also Chawla LS, et al., Acute kidney disease and renal recovery: consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup. Nat Rev Nephrol. 2017;13(4):241-257).

[0387] 4. Dose Rationalization

[0388]

[0389] There is uncertainty in the underlying assumptions of the specific background MAG rate and treatment effect assumptions in this risk group. Therefore, two interim analyses of this study were conducted to determine futility and the need for sample size re-estimation.

[0390] Safety outcomes being evaluated are often used in clinical studies that comply with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) and Good Clinical Practice (GCP) guidelines.

[0391] 5. Study Population

[0392] The dose in this study is the same as the weight-based maintenance dose of ravulizumab that has been approved for adults with aHUS, PNH, or gMG, and the safety of this dose has been established.

[0393] This dose ensures a ravulizumab serum concentration ≥175 μg / mL to achieve complete terminal complement inhibition, while maintaining the maximum ravulizumab serum concentration below the highest observed value of 3000 μg / mL from all completed clinical studies in the target patient population for at least 18 days. The 175 μg / mL threshold was previously identified as the minimum therapeutic concentration of ravulizumab required to achieve complete terminal complement inhibition.

[0394] To support this dosing regimen, model-based simulations were conducted (Ravulizumab CSA-AKI Dose Rationale, 2022). Briefly, the population PK model used for simulation was from the aHUS label extension dossier. Factors that could potentially affect the PK of ravulizumab in the target patient population were incorporated into the model simulation and included the effects of proteinuria, red blood cell transfusions, and postoperative hemodilution.

[0395] Other non-quantifiable factors such as drug loss or the complement pathway activated by CPB were not included in the simulation. Therefore, in the case of CSA-AKI, a dose capable of achieving a ravulizumab concentration of at least 175 μg / mL for at least 18 days is required and is predicted by the proposed weight-based single-dose of ravulizumab.

[0396] If a participant has completed the primary assessment period, he / she is considered to have completed the study. The end of the study is defined as the date of the last participant's last visit as indicated in the activity schedule.

[0397] 6. Study Interventions

[0398] To be eligible to participate in the study, participants must meet all of the following criteria:

[0399] 1. ≥18 years old to ≤90 years old at the time of signing the informed consent form.

[0400] 2. Male or female. Female participants of childbearing potential and male participants must follow the contraceptive guidance specified in the protocol.

[0401] 3. Body weight ≥30 kg at screening.

[0402] 4. Scheduled non-emergency sternotomy using CPB procedure for the following surgeries: multivessel CABG, valve replacement or repair; ascending aorta surgery is allowed if combined with aortic valve replacement / repair, combined CABG and valve surgery; single-vessel CABG is allowed when combined with valve replacement / repair. Note: The surgery should be scheduled within 35 days of screening (up to 28-day screening period, randomized and dosed 1 day to 7 days before CPB).

[0403] 5. Known CKD (stage 3A, 3B or 4) for at least 3 months, eGFR ≥20 to <60 mL / min / 1.73 m2, eGFR is confirmed at screening (repeatable once during the screening period) and at randomization using the CKD-EPI equation measured by sCr or sCysC, and the sCr or sCysC measurement is obtained from a local or central laboratory.

[0404] 6. At risk of postoperative AKI as defined by a minimum STS calculator renal failure risk score of 3%.

[0405] 7. Able to give a signed informed consent form that includes compliance with the requirements and restrictions listed in the informed consent form and this protocol.

[0406] If any of the following criteria apply, the participant is excluded from the study:

[0407] 1. As evaluated by the researchers, emergency or salvage cardiac surgery is expected to be performed at the time of screening or randomization.

[0408] 2. Single-vessel CABG with planned valve-less surgery.

[0409] 3. Surgery planned without the use of cardiopulmonary bypass (e.g., surgery without CPB).

[0410] 4. Any use of KRT or the presence of AKI within 30 days of randomization (AKI is defined as a 1.5-fold increase in sCr relative to baseline), except for transient (≤5 days) stage 1 AKI after iodinated contrast exposure.

[0411] 5. Recipients of solid organ or bone marrow transplantation.

[0412] 6. Cardiogenic shock, hemodynamic instability, use of an intra-aortic balloon pump, extracorporeal membrane oxygenation, or placement of a cardiac assist device within 72 hours of randomization.

[0413] 7. Active systemic bacterial, viral, or fungal infections within 14 days prior to randomization.

[0414] 8. Participants with a history of human immunodeficiency virus (HIV) but not on antiretroviral therapy, or if on therapy, with a known detectable viral load within 1 year of screening.

[0415] 9. Congenital immunodeficiency.

[0416] 10. History of unexplained recurrent infections.

[0417] 11. Known medical or psychological conditions, including substance abuse, or risk factors that, in the opinion of the researchers, may interfere with the full participation of the participant in the study, pose any additional risk to the participant, or confound the assessment of the participant or the study results.

[0418] 12. History of Neisseria meningitidis (N. meningitidis) infection or untreated Neisseria meningitidis infection.

[0419] 13. Allergy to any component contained in the study intervention, including allergy to murine proteins.

[0420] 14. Current malignancy or treatment for malignancy

[0421] 15. Use of any complement inhibitor, or plasmapheresis or plasma exchange within 1 year prior to screening, or planned during the course of the study.

[0422] 16. Planned use of any agent specifically for the prevention or treatment of AKI.

[0423] 17. It is planned to use KRT, intra-aortic balloon pump, extracorporeal membrane oxygenation, or leave a cardiac assist device in place between randomization and surgery.

[0424] 18. Participate in another interventional treatment study or use any experimental treatment within 30 days before the start of the study intervention on Day 1 of this study or within 5 half-lives of this IP, whichever is greater, or plan to participate in / use during the course of the study.

[0425] 19. There is a do-not-resuscitate order or life expectancy < 3 months.

[0426] 20. Pregnant, breastfeeding, or intending to become pregnant within 8 months after the study intervention dose.

[0427] 21. The participant is unwilling to receive the Neisseria meningitidis vaccine or, if required, prophylactic treatment with appropriate antibiotics.

[0428] Screening failure is defined as a participant who consented to participate in the clinical study but was not subsequently randomly assigned to the study intervention. A minimum set of screening failure information is required to ensure transparent reporting of screening failure participants to meet the reporting requirements of the Consolidated Standards of Reporting Trials (CONSORT) and to respond to queries from regulatory agencies. The minimum information includes demographics, screening failure details (e.g., failed eligibility criteria), and any adverse events (AEs), including any serious adverse events (SAEs) and any concomitant medications that occurred during the screening period.

[0429] Individuals who do not meet the criteria for participation in this study (screening failure) due to reasons that are expected to resolve or have resolved may be re-screened based on discussion and protocol. Participants re-screened outside the screening window need to sign a new informed consent form (ICF).

[0430] Table 5: Study Interventions

[0431] The study intervention is defined as any investigational intervention, commercially available product, or placebo that is intended to be administered to study participants according to the study protocol.

[0432] Participants will be randomized to ravulizumab or placebo. Ravulizumab is formulated at pH 7.0 and supplied in 30 mL single-use vials. Each vial of ravulizumab contains 300 mg of ravulizumab (10 mg / mL) in 10 mM sodium phosphate, 150 mM sodium chloride, 0.02% polysorbate 80, and water for injection. The comparator product (placebo) is formulated as a matching sterile solution with the same buffer components but without the active ingredient. Additional details are presented in Table 5.

[0433] Study Intervention Name

[0434] Ravulizumab Placebo Dose Formulation Vial Vial Physical Description Nearly particle-free liquid solution Nearly particle-free liquid solution Unit Dose Strength 300 mg (10 mg / mL concentrated solution) Placebo Route of Administration Intravenous infusion Intravenous infusion Use Experimental Placebo Comparator Table 6: Single Dose of Ravulizumab or Placebo Based on Body Weight

[0435] Participants randomized to the ravulizumab group received a single weight-based dose of ravulizumab from 1 to 7 days (i.e., at least 1 calendar day) before the CPB procedure. This dose was the same as the weight-based maintenance dose of ravulizumab approved for adult patients with aHUS, PNH, or gMG (Table 6).

[0436] Body Weight

[0437] Dose 2700 mg ≥30 kg < 40 kg 3000 mg ≥40 kg < 60 kg 3300 mg ≥60 kg < 100 kg ≥100 kg 3600 mg 7. Study Assessments and Procedures

[0438] At a minimum, study interventions are labeled with: protocol number, batch number / expiration date, name and address, and instructions for use and storage. Study interventions are labeled in accordance with national regulatory requirements.

[0439] When study interventions arrive at the study site, the study intervention kits are removed from the shipping container and stored in their original cartons under refrigeration at 2°C to 8°C (35°F to 47°F) and protected from light. Study interventions are not frozen. For all received study interventions, the investigator must confirm that appropriate temperature conditions have been maintained during shipping and report and resolve any discrepancies before using the study intervention. Store study interventions in a secure, limited-access storage area and monitor the temperature daily.

[0440] Prepare infusions of study interventions using aseptic technique. Ravulizumab and placebo are further diluted with a compatible diluent at a ratio of 1:1. During the infusion, both ravulizumab and placebo are administered using a 0.2 micron filter.

[0441] Only study participants may receive study interventions, and only authorized site personnel may supply or administer study interventions. All study interventions must be stored in a secure, environmentally controlled, and monitored (manually or automatically) area according to the labeled storage conditions, and access is limited to investigators and authorized site personnel.

[0442] In this study, participants in both treatment groups received standard of care as background therapy.

[0443] Eligible participants were randomly assigned to the ravulizumab group or the placebo group at a 1:1 allocation ratio. Randomization was conducted centrally using interactive response technology (IRT).

[0444] To balance the effects of potential confounding factors between the ravulizumab and placebo groups, randomization was stratified by baseline CKD stage (3A, 3B, 4) confirmed at screening and baseline CKD-EPI based on sCr or sCysC (local or central laboratory results), and type of surgery (mitral valve replacement or combined procedure vs. other single procedures).

[0445] Participants, all study site personnel, and any designated individuals directly involved in the conduct of the study were blinded to the participant treatment assignment throughout the study. Blinding was maintained by using identical study intervention kits and the labeling of ravulizumab and placebo. The placebo had the same appearance as ravulizumab. The randomization code was maintained by the IRT provider.

[0446] Infusion of the study intervention to participants was under the supervision of the investigator or their designee to ensure that participants received the appropriate dose at the appropriate time points during the study. The date and time of dose administration were recorded. Concomitant therapies

[0447] Any medications or therapies (including over-the-counter or prescription medications, vaccines, vitamins, and / or herbal supplements) considered necessary for the care or treatment of any adverse events in participants during the study, as well as any other medications, except those listed as prohibited medications, were administered at the discretion of the investigator. It was the responsibility of the investigator to record all medications and: reason for use, date of administration (including start and end dates), and dose information (including dose and frequency).

[0448] Participants were prohibited from receiving any of the following medication endpoints (90 days after CPB): eculizumab, ravulizumab (except as the protocol-specified study intervention), or other agents acting on the complement pathway, plasmapheresis or plasma exchange, and any agent specifically used to prevent or treat AKI (e.g., experimental or investigational fenoldapam, levosimenden, and nesiritide, etc.). These therapies could be used for their approved indications.

[0449] Unless clinically indicated, KRT, intra-aortic balloon pump, extracorporeal membrane oxygenation, or left ventricular assist should be avoided after administration of the study intervention and before surgery. Use of these procedures after the study intervention and before surgery was considered a confounding procedure because these procedures could trigger AKI before CPB or confound the proper diagnosis and staging of AKI (e.g., use of KRT). These procedures were considered the standard of care during the surgical and postoperative phases and were permitted.

[0450] Dose modification of the study intervention for individual participants was not permitted in this study.

[0451] 8. Efficacy Assessments

[0452] The research procedures and their timings are summarized in the assessment schedule shown in Figure 2. Protocol waivers or exemptions are not permitted. Adherence to the research design requirements, including those specified in the assessment schedule, is necessary and required for the conduct of the study. All screening assessments must be completed and reviewed to confirm that potential participants meet all eligibility criteria. Maintain a screening log to record details of all screened participants and confirm eligibility or record reasons for screening failure, if applicable.

[0453] Procedures that are part of the routine clinical management of participants (e.g., blood cell counts) and that are available for screening purposes prior to signing the informed consent form, provided that the procedures meet the criteria specified in the protocol and are conducted within the time frame defined in the assessment schedule.

[0454] Duplicate or unscheduled samples may be obtained for safety reasons or for technical issues with the samples.

[0455] Prior to conducting any research-related procedure, the researcher or a qualified designee must obtain a signed and dated informed consent form from each participant. Prior to conducting screening procedures, every effort should be made to ensure that participants comply with the research participation regulations.

[0456] All inclusion and exclusion criteria must be reviewed by the researcher or a qualified designee to ensure that participants are eligible to participate in the study. The researcher maintains a screening log to record details of all screened participants and confirm eligibility or record reasons for screening failure, if applicable. Eligibility is determined prior to randomization.

[0457] The study aims to enroll participants in non-emergency cardiac surgery, as judged by the researcher. For guidance, elective cardiac surgery is described in Bojar RM., “Manual of Perioperative Care in Adult Cardiac Surgery”, 6th Edition 2021 Print ISBN: 9781119582557, and is as follows: The cardiac function of the patient is stable in the days or weeks prior to surgery, and / or the procedure can be postponed without increasing the risk of impaired cardiac outcomes.

[0458] Emergency cardiac surgery is defined as the procedure required during the same hospitalization to minimize the chance of further clinical deterioration. This includes but is not limited to: deteriorating or sudden chest pain, heart failure, acute myocardial infarction, potential anatomy, unstable angina with intravenous nitroglycerin (IV NTG), and rest angina. Any of these conditions requires the patient to remain in the hospital until surgery can be performed, but the patient can wait for surgery until the next available OR schedule time. Surgery may need to be postponed due to attempts to improve the patient's condition, availability of spousal or parental informed consent, availability of blood products, or availability of necessary laboratory procedures or test results. The definition of an emergency procedure includes the use of IABP; however, the use or planned use of IABP was excluded separately in this study.

[0459] Participants requiring emergency or salvage cardiac surgery were not enrolled at the discretion of the investigators. For guidance, emergency cardiac surgery is defined as surgery without any delay for ongoing, refractory (difficult, complex, and / or unmanageable), relentless cardiac compromise, with or without hemodynamic instability, and unresponsive to any form of treatment other than cardiac surgery. Examples include the hemodynamic picture of shock supported by chemicals or machinery, such as IV inotropes or IABP to maintain cardiac output, pulmonary edema requiring intubation and ventilation, expanding myocardial infarction, signs of persistent ischemia i.e., ECG changes, acute native valve dysfunction (acute papillary muscle rupture or leaflet tear), prosthetic valve dysfunction with structural failure (valve rupture or leaflet tear, thrombosis, development of pannus obstructing flow across the valve orifice, or valve dehiscence), acute aortic dissection, rupture or dissection during cardiac catheterization; and perforation and tamponade after cardiac catheterization.

[0460] Salvage cardiac surgery is defined as surgery for a patient who has experienced CPR or continuous use of ECMO to maintain life on the way to the OR before anesthesia induction.

[0461] Demographic parameters, including age, sex, race, and ethnicity (required for calculating the STS risk score and eGFR), were recorded in the clinical research report (CRF).

[0462] Due to its mechanism of action, the use of ravulizumab increases the susceptibility of participants to meningococcal infection caused by Neisseria meningitidis. To reduce the risk of infection, all participants must be vaccinated against Neisseria meningitidis within 3 years prior to the administration of the study intervention. If a participant has not been vaccinated within 3 years of the administration of the study intervention, vaccination occurs at any time during screening or until discharge. If the study intervention is administered <2 weeks after the primary vaccination, the participant should receive prophylactic antibiotics against meningococcal infection at most 2 weeks after vaccination. Hospitalized participants may be vaccinated after the administration of the study intervention but before discharge. These participants receive prophylactic treatment with appropriate antibiotics for at least 2 weeks starting from the day of administration after vaccination.

[0463] Vaccines against serotypes A, C, Y, W135 and available serotype B (if recommended by local guidelines) are recommended for the prevention of meningococcal serotypes that are often pathogenic. Participants must receive a complete primary vaccination series and be revaccinated if indicated according to current national vaccination guidelines. Vaccination may not be sufficient to prevent meningococcal infection.

[0464] The use of prophylactic antimicrobials should follow official guidance and local practice. Monitor all participants for early signs of meningococcal infection, evaluate immediately if infection is suspected, and treat with appropriate antibiotics if necessary.

[0465] To increase risk awareness and facilitate the rapid disclosure of any potential signs or symptoms of meningococcal infection experienced by participants during the study, participants are provided with a Participant Safety Card to carry at all times. Additional discussions and explanations of potential risks, signs, and symptoms occur at specific time points as part of the review of the Participant Safety Card and throughout the study as described in the assessment schedule.

[0466] The relevant medical history of participants, including previous and concomitant medical conditions / diseases, treatment history, and disease status of relevant diseases, is evaluated at screening and recorded in source documents and CRFs. Record all medical history, previous medications and procedures starting from 2 years prior to screening, and any medical history starting from any time related to heart or kidney disease, including the identified cause of the participant's kidney disease. Record any changes in medical history that occur during the screening period and before the administration of the study intervention on Day 1.

[0467] The Society of Thoracic Surgeons (STS) risk calculator is used to determine the preoperative risk of severe AKI (RIFLE failure criteria) based on the baseline characteristics of the participants required by the risk calculator. The risk score and the participant characteristics used to determine the risk score are captured during the screening period before the administration of the study intervention on Day 1. Calculate the EuroScore separately and record the value.

[0468] When available, home visits are permitted after discharge. Home visits are conducted by qualified medical professionals in accordance with all national, state, and local laws or regulations of the relevant regulatory agencies. Telehealth visits may occur in conjunction with home visits.

[0469] All assessments may be conducted during home visits under the guidance of the researcher. The information collected must be transferred to the researcher's site for assessment on the day of the visit. In the case of any symptoms or signs indicating a serious adverse event, further assessment of the participant may be required at the study site or an emergency care facility.

[0470] 9. Adverse Events (AE) and Serious Adverse Events (SAE)

[0471] For the primary efficacy endpoint, the participant's major acute kidney event (MAKE) is evaluated 90 days after cardiac surgery using CPB. MAKE90 is defined as meeting at least one of the following criteria: (1) a ≥25% decrease in eGFR (CKD-EPI formula using sCysC) from baseline on day 90 after CPB, or (2) initiation of KRT by day 90 after CPB, or (3) death for any reason by day 90 after CPB.

[0472] In addition, secondary endpoints evaluate AKI and MAKE endpoints at additional time points. To enable these efficacy assessments, the researcher collects and records:

[0473] A. sCr and sCysC at screening day, dosing day (day 1), surgical day before induction of anesthesia, days 1 - 7, 15, 30, 60, and 90 after CPB, and at discharge:

[0474] Unless the participant is discharged before day 7 after CPB, sCr and sCysC are collected daily from day 1 to day 7 after CPB (168 hours, visit 5). However, daily laboratory tests for the presence of AKI are performed until day 7 after CPB, even if discharged, or until recovery (<1.5× baseline), whichever comes first.

[0475] B. Record the highest sCr observed by the local laboratory from the end of CPB to day 30.

[0476] C. Any use of KRT from randomization to day 90 after CPB. Record the type / modalities, frequency, start / stop, and reasons for start / stop of KRT. All attempts collected at the lowest KRT status (yes / no) must be performed and recorded at days 15, 30, 60, and 90. The use of surgical ultrafiltration during cardiac surgery as a standard of care procedure for routine management of fluid balance is not considered initiation of KRT and is recorded as an adjunctive procedure.

[0477] D. Any death from randomization to day 90 after CPB. The date of death is collected and recorded, and any related adverse events / serious adverse events are reported, including causal serious adverse events leading to death. All attempts to collect at the lowest vital status (survived, yes / no) must be made and recorded at days 15, 30, 60, and 90.

[0478] All efforts are made to collect laboratory test samples, KRT status, KRT details, and survival status at all visits. However, if needed, the KRT status (yes / no), KRT details, and survival can be determined directly by telephone or telemedicine visit. If attempts to contact the participant directly fail, the KRT status and survival status can be obtained indirectly from family members, other healthcare providers, or the local death registry.

[0479] The planned time points for all safety assessments are provided in the assessment schedule.

[0480] Examinations for symptoms can be performed at any time after screening as needed according to local practice / care standards; normal findings or findings consistent with the participant's medical history are not recorded; abnormal findings, new abnormalities, or worsening of physical findings not attributable to the participant's medical history are reported as adverse events. The researchers must pay special attention to clinical signs related to previous serious diseases. Height is measured only at screening. Weight is measured before induction of anesthesia on the day of surgery. Daily weight is measured for the first 7 days after CPB or until discharge (whichever comes first). If an accurate weight cannot be obtained in the intensive care unit (ICU) setting, total daily fluid intake and output are recorded in lieu of weight measurement. Temperature (°C or °F), heart rate, respiratory rate, and systolic and diastolic blood pressure (mmHg) are evaluated. Blood pressure and pulse measurements are evaluated using fully automated equipment with the participant in a sitting position. In the event that the participant cannot tolerate sitting measurements (e.g., when on mechanical ventilation in the ICU), the measurements can be made in the supine position and recorded. Manual techniques are used only if automated equipment is not available. Blood pressure and pulse measurements are made after the participant has rested for at least 5 minutes in a quiet environment without distractions (e.g., television, mobile phone). Ideally, each participant has measurements made using the same arm. Vital signs are collected before the dose on day 1.

[0481] Electrocardiogram (ECG) for symptoms can be performed at any time after screening as needed according to local practice / care standards. Normal findings or findings consistent with the participant's medical history are not recorded. Abnormal findings, new abnormalities, or worsening of previous ECG findings not attributable to the participant's medical history are reported as adverse events. The participant must lie supine for approximately 5 to 10 minutes before ECG collection and remain supine but awake during ECG collection.

[0482] All protocol-required laboratory evaluations are conducted according to the laboratory manual and the evaluation schedule. Samples are collected as follows for clinical laboratory evaluation: before the administration of the study intervention on Day 1, before induction of anesthesia on the surgical day, at any time during other visits, and within 1 day of discharge. Daily sample collection for clinical laboratory evaluation occurs on Days 1 to 7 after CPB as follows: sCr and sCysC are collected on Days 1, 2, 4, 5, and 6 after CPB at hospital admission, and a complete laboratory evaluation is performed on Days 3 and 7 after CPB. If discharge occurs before Day 7 after CPB and the participant has no AKI, sCr and sCysC on Days 1, 2, 4, 5, or 6 do not need to be collected. Participants who develop any AKI (at least stage 1 according to KDIGO criteria) within the first 7 days, regardless of their discharge status, will receive daily laboratory tests until Day 7 after CPB or recovery (<1.5× baseline) (whichever comes first). On Days 3 and 7, samples for clinical laboratory evaluation are collected as described in the evaluation schedule.

[0483] During the entire 90-day visit study participation period, all safety laboratory tests with values considered clinically significantly abnormal are repeated until the values return to normal or baseline or are no longer considered clinically significant. If such values do not return to normal / baseline within a period of time, the causative source should be identified.

[0484] If safety laboratory values from non-protocol-specified laboratory evaluations conducted at the institution's local laboratory require a change in participant management or are considered clinically significant (e.g., adverse event or serious adverse event or dose modification), the results are recorded in the CRF, and the corresponding adverse event or serious adverse event is reported.

[0485] Pregnancy tests are performed on all women of childbearing potential (WOCBP) at the protocol-specified time points in the evaluation schedule. Pregnancy tests can also be performed at any time during the study. WOCBP require a negative pregnancy test before the administration of the study intervention. Any female participant who is pregnant at the time of study participation is withdrawn from the study intervention. Pregnancy is not considered an adverse event unless it is suspected that the study intervention may have interfered with the effectiveness of contraceptive medications. However, complications of pregnancy and abnormal outcomes of pregnancy are adverse events and may meet the criteria for serious adverse events (e.g., ectopic pregnancy, spontaneous abortion, intrauterine fetal death, neonatal death, or congenital anomaly).

[0486] During the primary evaluation period, the vital status (survived, yes / no) was recorded at 15, 30, 60, and 90 days after CPB. For participants who withdrew consent to further participate in the study, all efforts were made to collect data at the time of withdrawal. During the survival follow-up period, the vital status was recorded at 365 days after CPB or ED, whichever came first.

[0487] The vital status of the participants was obtained via telephone contact with the participants, the participants' families, contact with another healthcare provider, or the local death registry.

[0488] Table 7: SAE

[0489] An AE is any adverse medical event in a clinical study participant who has received a drug product and does not necessarily have to be causally related to the treatment. Thus, an AE can be any adverse and unexpected sign (including abnormal laboratory findings), symptom, or disease (new or worsening), whether or not considered related to the study intervention, that is temporally associated with the use of the study intervention.

[0490] The following events meet the AE definition:

[0491] A. Any abnormal laboratory test result (hematology, clinical chemistry, or urinalysis) or other safety assessment (e.g., ECG, radiological scan, vital sign measurement), including deterioration from baseline, that is considered clinically significant (i.e., not related to the progression of the underlying disease).

[0492] B. Deterioration of a chronic or intermittent pre-existing condition, including

[0493] an increase in the frequency and / or intensity of the condition.

[0494] C. A new condition detected or diagnosed after administration of the study intervention,

[0495] even if the condition may have been present before the start of the study.

[0496] D. Signs, symptoms, or clinical sequelae of a suspected drug-drug interaction.

[0497] E. Signs, symptoms, or clinical sequelae of a suspected overdose of the study intervention or co-administered medication. An overdose itself is not reported as an AE / SAE unless it is an intentional overdose with a possible suicidal / self-harm intent. Report such an overdose regardless of the sequelae.

[0498] Events that do not meet the AE definition include:

[0499] A. Medical procedure or surgical procedure (e.g., endoscopy, appendectomy): The condition that led to the procedure is AE, and the procedure itself is recorded as an accompanying procedure. Situations where no adverse medical event occurs (e.g., hospitalization for elective surgery if planned before signing the ICF, admission for social reasons or for convenience).

[0500] B. The expected daily fluctuations of pre - existing diseases or conditions present or detected at the start of the study do not worsen.

[0501] C. Medication errors (including intentional misuse, abuse, and overdose of products) or use other than as defined in the protocol are not considered AEs unless there is an adverse medical event due to the medication error.

[0502] D. Pregnancy that occurs during the exposure of the mother or father to the study intervention should be reported within 24 hours after the researcher / site becomes aware. Data on fetal outcomes and breastfeeding are collected for regulatory reporting and safety assessment.

[0503] E. Any clinically significant abnormal laboratory findings or other abnormal safety assessments related to the underlying disease, unless the researcher determines them to be more severe than expected for the participant's condition.

[0504] F. The disease / condition under study or the expected progression, signs, or symptoms of the disease / condition under study, unless they are more severe than expected for the participant's condition.

[0505] G. Situations where no adverse medical event occurs (social and / or convenience admission).

[0506] H. "Lack of efficacy" or "failure of the expected pharmacological effect" itself does not report an AE or SAE. Such situations are captured in the efficacy assessment. However, if the signs, symptoms, and / or clinical sequelae resulting from lack of efficacy meet the definition of an AE or SAE, they are reported as an AE or SAE.

[0507] If an event is not an AE as defined above, then even if it meets severe conditions (e.g., hospitalization for signs / symptoms of the disease under study, death due to disease progression), the event cannot be an SAE.

[0508] An SAE is defined as any adverse medical event that meets one or more of the criteria listed in Table 7 at any dose.

[0509] 10. Pharmacokinetics (PK) and Pharmacodynamics (PD)

[0510]

[0511] A suspected unexpected serious adverse reaction (SUSAR) is defined as an event that is assessed as serious, is not listed in the appropriate reference safety information (IB), and has been evaluated to have at least a reasonable possibility of being related to the investigational medicinal product.

[0512] The investigators evaluated each AE and SAE reported during the study and assigned it to one of the following categories from the National Cancer Institute CTCAE v5.0 published on November 27, 2017: Grade 1: Mild (awareness of signs or symptoms, but easily tolerated), Grade 2: Moderate (discomfort sufficient to cause interference with normal activities), Grade 3: Severe (disabling, unable to carry out normal activities), Grade 4: Life-threatening, or Grade 5: Fatal. An event was defined as "serious" when it met at least one of the predefined outcomes described in the definition of SAE, rather than when it was rated severe.

[0513] The investigators were obliged to evaluate the relationship between the study intervention and each occurrence of an AE or SAE. A causality assessment by the investigators had to be provided for all AEs (non-serious and serious). This assessment had to be recorded in the eCRF and on any additional forms as appropriate. The definition of the causality assessment was as follows:

[0514] A. Not related: There is no reasonable possibility that the study intervention caused the AE. The AE has a more likely alternative causative source; it may be due to underlying or concurrent disease, complications, concurrent treatment, or the action of another concurrent medication. The event does not follow a reasonable temporal relationship with the administration of the study intervention.

[0515] B. Related: There is a reasonable possibility that the study intervention caused the AE. The AE has a temporal relationship with the administration of the study intervention. The event does not have a likely alternative causative source. The event corresponds to the known drug profile of the study intervention. There is improvement after interruption and / or recurrence after readministration

[0516] The investigators used clinical judgment to determine the relationship. Alternative causes such as underlying disease, concomitant therapies, and other risk factors were considered and investigated, as well as the temporal relationship of the event with the administration of the study intervention. The investigators also consulted the IB and / or product information of the marketed product in their assessment. For each AE / SAE, the investigators had to record in the medical record that they had reviewed the AE / SAE and had provided a causality assessment.

[0517] Intravenous and infusion-related reactions are potential risks associated with the use of monoclonal antibodies; these reactions can be non-immune or immune-mediated (e.g., allergic reactions). Signs and symptoms can include headache, fever, flushing, itching, myalgia, nausea, chest tightness, dyspnea, vomiting, erythema, abdominal discomfort, diaphoresis, tremors, hypertension, confusion, hypotension, palpitations, and somnolence. Signs and symptoms of anaphylaxis or allergic reactions can include urticaria, swelling of the face, eyelids, lips, or tongue, or dyspnea.

[0518] Report all administration, IV, and infusion-related reactions to the researchers and the qualified designated personnel. The researchers and the qualified designated personnel are responsible for detecting, recording, and documenting events that meet the definition of an AE or SAE, and remain responsible for following up on serious events, events considered related to the study intervention or study procedure; or events that lead to the discontinuation of ravulizumab in the participant. Participants who experience a reaction during the administration of ravulizumab are treated according to institutional guidelines. Participants who experience a severe reaction during the administration of ravulizumab that leads to the discontinuation of ravulizumab undergo all planned safety, PK, and PD assessments required by the protocol. All AEs that may indicate an infusion-related reaction are graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0 or higher.

[0519] If anaphylaxis occurs according to the criteria listed in Table 8, consider administering subcutaneous epinephrine (1 / 1000, 0.3 mL to 0.5 mL, or equivalent). In the case of bronchospasm, treatment with an inhaled β-agonist is also considered. Participants who receive an antihistamine for the treatment or prevention of infusion-related reactions are given appropriate warnings about drowsiness and impaired driving ability before leaving the center.

[0520]

[0521] Meningococcal infection is considered an Adverse Event of Special Interest (AESI).

[0522] For this study, any dose of the study intervention greater than that specified in the protocol is considered an overdose. If the dose cannot be determined due to blinding, a suspected overdose is defined by the volume administered.

[0523] An accidental overdose or suspected overdose not associated with any laboratory abnormalities or clinical symptoms is not considered an AE. The researchers must report the overdose within 24 hours, regardless of whether it is associated with an AE.

[0524] An overdose is a medication error that is not considered an AE unless there is an adverse medical event resulting from the overdose.

[0525] 11. Statistical Considerations

[0526] Blood samples for the determination of serum ravulizumab concentration and PD assessment (free C5) are collected at the time points specified in the assessment schedule before and after the administration of the study intervention. The actual date and time (24-hour clock time) of each sample are recorded.

[0527] On Day 1, baseline PK and PD blood samples are collected within 30 minutes before the administration of the study intervention at the pre-dose and at the visits specified in the assessment schedule. The Day 1 pre-dose blood sample can be drawn through the intravenous access created for the drug infusion before the administration of the dose.

[0528] Post-dose PK and PD blood samples are collected within 30 minutes after the completion of the study intervention infusion. The post-dose blood sample is drawn from the contralateral, non-infused arm of the participant. Samples can be collected at any visit time after Day 1. In the event of an unscheduled visit, PK and PD blood samples are collected as soon as possible.

[0529] Before the study has been unblinded, information on the concentration of the study intervention that may unblind the study is not reported to the study site or the blinded personnel.

[0530] Genetics is not evaluated in this study.

[0531] Blood (serum and plasma) samples for exploratory assessment are collected from all participants at the time points specified in the assessment schedule. Biomarkers may include, but are not limited to, the following assessments: (1) complement pathway activation (e.g., soluble C5b-9 [sC5b-9]), (2) endothelial injury and / or activation (e.g., thrombomodulin [TM]), (3) vascular inflammation (e.g., soluble tumor necrosis factor receptor I [TNF-RI]), and (4) inducers of cell cycle arrest (e.g., tissue inhibitor of metalloproteinase-2 [TIMP-2]).

[0532] Urine samples for exploratory assessment are collected from all participants at the time points specified in the activity schedule. Biomarkers include, but are not limited to, the following assessments: (1) complement pathway activation (e.g., sC5b-9), and (2) kidney injury (e.g., neutrophil gelatinase-associated lipocalin [NGAL]).

[0533] Residual blood and urine samples from exploratory biomarkers, PK, PD, and immunogenicity are stored for additional assessment (e.g., related to the study intervention target, disease course, pathways related to disease state, other complement-related diseases, and / or the mechanism of action of ravulizumab). Samples are maintained for no more than 5 years after study termination or other periods according to local requirements.

[0534] The quality of life scale is completed by the participants before other study procedures at the visits specified in the assessment schedule.

[0535] Participants in both arms completed the following validated quality of life scales:

[0536] The Kidney Disease Quality of Life Short Form-36 (KDQOL-36) (Section 10.7), a 36-item short-form survey, is a widely used measure for dialysis patients. Participants were asked to answer questions about their health, kidney disease, and the impact of kidney disease on their daily lives.

[0537] The 5-dimension 5-level (EQ-5D-5L) of the EuroQol Group (Section 10.7) is a standardized tool for self-assessment of health-related quality of life and has been used in a wide range of health conditions. The EQ 5D 5L is a 5-dimensional participant-reported outcome tool that measures pain / discomfort, mobility, self-care, usual activities, and anxiety / depression.

[0538] The Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue Scale (Version 4.0) is a 13-item questionnaire that assesses self-reported fatigue and its impact on daily activities and function over the previous 7 days.

[0539] Healthcare resource utilization related to medical encounters for all participants was collected throughout the primary assessment period. Protocol-specified procedures, tests, and encounters were excluded. Hospitalizations from admission to discharge, including the admission date, discharge date, and dates of ICU admission and transfer to another inpatient ward). Renal replacement therapy (KRT): type / mode, frequency, start and stop dates, and reasons for start / stop. Duration of mechanical ventilation (dates and start / stop times). Discharge destination (e.g., home, rehabilitation facility, hospice).

[0540] Readmissions (emergency department or inpatient hospitalizations; elective outpatient procedures occurring in the hospital are not considered readmissions). The primary reasons were evaluated as: preoperatively, if present, cardiovascular events (e.g., MI, stroke, heart failure, arrhythmia), AKI, or other reasons that always did not require reoperation. Hospitalizations from readmission to discharge, including the date of entry into the emergency department, inpatient admission date, discharge date, and dates of ICU admission and transfer to another inpatient ward. The specific reasons for readmission were reported as AE / SAE.

[0541] Additional data collected (e.g., concomitant medications, and outpatient diagnoses and treatment procedures) were used for exploratory economic analyses.

[0542] Other exploratory endpoints included: (1) AKI within 7 days after CPB based on sCysC, (2) the highest AKI stage according to KDIGO criteria, and (3) absence of severe AKI (KDIGO stage 2 or 3).

[0543] The minimum follow-up for safety is 90 days from the administration of the study intervention (Day 1, Visit 2). Participants in the study received a single weight-based dose of the study intervention and had cardiac surgery using CPB within 1 to 7 days of dosing (the maximum interval between dosing and cardiac surgery using CPB was 15 days in case of unexpected surgical delays), and all study visits and procedures as outlined in the assessment schedule were conducted up to the 90-day visit (Visit 9). The timing of the postoperative (post-CPB) visits at Days 3, 7, 15, 30, 60, and 90 was based on the number of days of CPB, and Day 1 post-CPB was defined as the number of days after the participant completed CPB. However, additional situations may arise during the conduct of the study: If a participant is dosed with the study intervention and does not have cardiac surgery, or if the surgery is delayed more than 15 days after dosing, the participant undergoes all subsequent study visits and procedures as outlined in the assessment schedule up to the 90-day visit, where the timing of the visits is based on the dosing day (Day 1, Visit 2). If a participant is randomized but not dosed, the participant undergoes all study visits and procedures as outlined in the assessment schedule up to the 90-day visit, where the timing of the visits is based on the randomization day (which is Day 1, Visit 2). If a participant withdraws, a decision for early discontinuation (ED) is made and Visit 9 is conducted immediately.

[0544] Antidrug antibodies (i.e., ADAs) against ravulizumab were evaluated in serum samples collected from all participants according to the assessment schedule. Additionally, serum samples were collected at the last visit from participants who discontinued the study intervention or withdrew from the study.

[0545] Serum samples were screened for antibodies that bind to ravulizumab, and the titers of confirmed positive samples were reported. Additional analyses may be performed to further characterize the immunogenicity of ravulizumab.

[0546] Detection and characterization of antibodies against ravulizumab were performed using validated assays. The ravulizumab serum concentration of samples collected for the detection of antibodies against ravulizumab was evaluated to assess the impact of ADAs on the drug concentration profile in ADA-positive patients. The antibody titers and the presence of neutralizing antibodies in ADA-positive samples were further characterized.

[0547] ADA variables included the incidence rate and titers of ADA response categories during the study, as follows. ADA response category definitions and titer thresholds were provided in the Statistical Analysis Plan (SAP). The ADA response categories were ADA negative and ADA positive. Participants who were ADA positive were classified as follows: pre-existing immunoreactivity or on-treatment ADA response.

[0548] Table 9: Analysis Population

[0549] The primary hypothesis tested in this study was that ravulizumab would be superior to placebo in reducing the risk of MAKE events at 90 days after CPB (MAKE90):

[0550] H0: p1 ≥ p0

[0551] H1: p1 < p0

[0552] where p1 and p0 represent the probabilities of experiencing MAKE90 events in the ravulizumab group and the placebo group, respectively.

[0553] The treatment effect based on the MAKE90 endpoint was estimated by the difference in the proportion of participants experiencing MAKE90, regardless of any concurrent events (IE) between the ravulizumab group and the placebo group. A negative difference indicates a beneficial treatment effect of ravulizumab.

[0554] Given that the null hypothesis of the primary endpoint was rejected, the following key secondary hypotheses were tested in the following hierarchical order. Ravulizumab was superior to placebo in the proportion of participants without CSA AKI at 90 days after CPB. Based on the highest sCr observed within 7 days after CPB, ravulizumab was superior to placebo in the proportion of participants without severe CSA-AKI (KDIGO stage 2 or 3). Based on the highest sCr observed within 30 days after CPB, ravulizumab was superior to placebo in the proportion of participants without severe AKI (RIFLE injury or failure criteria). Based on the highest sCr observed within 30 days after CPB, ravulizumab was superior to placebo in the proportion of participants without any severe AKI (KDIGO stage 2 or 3). Based on the highest sCr observed within 30 days after CPB, ravulizumab was superior to placebo in the proportion of participants without any RIFLE failure criteria. Ravulizumab was superior to placebo in the proportion of participants who died for any reason from randomization to 90 days after CPB.

[0555] Sample size estimation was based on the difference in two proportions, using the normal approximation method to compare the treatment difference in the proportion of participants experiencing MAKE events within 90 days after CPB between the ravulizumab group and the control group. Assuming a MAKE proportion of 25% in the placebo group and a MAKE proportion of 15% in the ravulizumab group, with a dropout rate of approximately 10%, the sample size was 736 (368 participants per treatment group) at a two-sided significance level of 0.05 with 90% power to detect a 10% statistically significant treatment difference in the proportion of participants with MAKE within 90 days after CPB. The assumption of a 25% MAKE90 rate in the placebo group was based on recent intervention and observational trials as described below.

[0556] Recent interventional trials aimed at reducing CSA-AKI have reported that 9% to 10% of placebo-treated participants reached the MAKE endpoint at day 30 (see, e.g., Meersch M et al., Intensive Care Med. 2017;43(11):1551-61; Jacob KA et al., J. Am. Soc. Nephrol. 2015;26(12):2947-51; Venugopal H et al., Kidney360. 2020;1(6):530-3) and 13% to 22% of placebo-treated participants reached the MAKE endpoint at day 90 (see, e.g., Thielmann M et al., Circulation. 2021;144(14):1133-1144; and Meersch M et al., Intensive Care Med. 2017;43(11):1551-61). These studies included variable proportions of participants with CKD (8% to 47%). Post hoc analyses of subsets of participants with CKD (preoperative eGFR <60 mL / min / 1.73 m2) from dexamethasone in cardiac surgery studies reported MAKE30 of 16.5% in the placebo group (see Venugopal H et al., Kidney360. 2020;1(6):530-3). Since these studies did not specifically enroll CKD patients, the placebo rate of this study is expected to be higher in the context of enrolling individuals with pre-existing CKD at increased risk of AKI, and the use of the STS risk calculator improved the predicted risk of renal failure.

[0557] For individuals with pre-existing CKD, data on the frequency of MAKE (or its individual component outcomes) from other trials are limited. Therefore, estimates of individual MAKE events were derived from observational studies as well as the trial data to inform the 25% placebo rate assumption for the current study:

[0558] KRT 7% to 10%: Intervention trials have reported KRT in 6.5% to 7.5% of participants receiving placebo (see, e.g., Thielmann M et al., Circulation. 2021;144(14):1133-1144; and Meersch M et al., Intensive Care Med. 2017;43(11):1551-61). Observational studies from multiple healthcare systems have reported postoperative KRT in 7% to 30% of patients with pre-existing CKD (see, e.g., Wu VC, Kidney Int. 2011;80(11):1222-1230; Cho JS et al., J. Thorac. Cardiovasc. Surg. 2021;161(2):681-8.e3; and Lau D et al., J. Thorac. Cardiovasc. Surg. 2021;162(3):880-7). By specifically recruiting participants with CKD, at least 7% of participants are expected to require KRT. The use of the STS renal failure risk calculation threshold in the study is also expected to enrich participants with the highest risk of requiring KRT, particularly among participants with pre-existing stage 3a CKD.

[0559] 4% to 7% mortality: Intervention trials have reported 2% to 7% mortality within 90 days after CPB (see, e.g., Thielmann M et al., Circulation. 2021;144(14):1133-1144; and Meersch M et al., Intensive Care Med. 2017;43(11):1551-61; Whitlock RP et al., Lancet. 2015;386(10000):1243-53; and Dieleman JM et al., JAMA. 2012;308(17):1761-7). In observational studies, AKI has been independently associated with the risk of death after CPB, with the highest risk among patients requiring acute KRT (see, e.g., Lau D et al., J. Thorac. Cardiovasc Surg. 2021;162(3):880-7; and Matsuura R et al., Sci Rep. 2020;10(1):6490). Additionally, AKI superimposed on pre-existing CKD confers a higher risk of death after cardiac surgery (up to 11%) (Cho 2021). Therefore, by enrolling only CKD patients, the overall mortality rate is expected to be approximately 5% to 6%.

[0560] SKD 17% to 25%: Using changes in sCr or sCr-based eGFR, 19% to 22% of the CKD population reported in observational studies had SKD at 3 months after CPB (see, e.g., Wu VC, Kidney Int. 2011; 80(11):1222 - 1230; Xu J et al., BMC Nephrol. 2019; 20(1):427; Matsuura R et al., Sci Rep. 2020; 10(1):6490; and Cho JS et al., J. Thorac. Cardiovasc. Surg. 2021; 161(2):681 - 8.e3). AKI superimposed on CKD is the greatest risk factor for SKD, with 20% to 30% not recovering to baseline renal function by 90 days (Cho 2021, Wu, 2011, Matsuura 2020). Data from interventional trials directly informing the rate of SKD in participants with pre-existing CKD are limited. Recent trials have reported SKD rates of 7% to 12% in control / placebo groups that were not fully enriched for CKD (see, e.g., Thielmann M et al., Circulation. 2021; 144(14):1133 - 1144; and Meersch M et al., Intensive Care Med. 2017; 43(11):1551 - 61). Compared to other CSA-AKI trials, the exclusive enrollment of participants with CKD was expected to increase the proportion of participants classified as SKD at 90 days.

[0561] MAKE90 20% to 30%: The frequencies of individual events are not additive because individual participants can often meet the criteria for >1 event within 90 days. Recent clinical trials (see, e.g., Thielmann M et al., Circulation. 2021; 144(14):1133 - 1144; and Meersch M et al., Intensive Care Med. 2017; 43(11):1551 - 61) have reported that approximately 30% of patients experienced more than 1 MAKE component (KRT, death, SKD). Assuming a similar pattern in the current study, based on the integration of the various data sources summarized herein, the expected proportion of participants in the placebo group reaching the MAKE endpoint at 90 days is estimated to be 20% to 30%; for this study, the assumed placebo rate is 25%.

[0562] The population sets used for analysis in this study are defined in Table 9.

[0563] 12. Clinical Laboratory Tests

[0564]

[0565] Abbreviations: ADA = anti-drug antibody; CPB = cardiopulmonary bypass; KRT = kidney replacement therapy; PD = pharmacodynamics; PK = pharmacokinetics; SAP = statistical analysis plan; sCr = serum creatinine.

[0566] Evaluable PK, PD, and ADA data were defined as non-missing results generated from samples that met sample integrity requirements during sample collection, storage, transportation, and bioanalysis.

[0567] Generally, descriptive statistics (n, mean, median, standard deviation, first and third quartiles, minimum, and maximum) were provided by treatment group and visit for each quantitative variable, and frequencies and percentages were provided by treatment group and visit for each qualitative variable. Graphical displays were provided as appropriate. Baseline was defined as randomization on Day 1 before administration of the study intervention, unless otherwise specified below. Final analysis and study unblinding were conducted once the last enrolled participant completed the Day 90 visit or withdrew early. Analysis was performed using software version 9.4 or higher.

[0568] The primary efficacy analysis was based on the intention-to-treat (ITT) analysis set. The primary endpoint was the MAKE event at 90 days after CPB (MAKE90), which was defined as meeting at least 1 of the following criteria: (1) a ≥25% decrease in eGFR from baseline at Day 90 after CPB, (2) occurrence of KRT by Day 90 after CPB, or (3) death for any reason by Day 90 after CPB. Baseline and post-baseline eGFR were calculated from sCysC using the CKD-EPI formula. Baseline eGFR was based on the mean of sCysC collected during screening and on Day 1 before administration of the study intervention.

[0569] Report the observed proportion of participants experiencing MAKE 90 by treatment group. The Cochran-Mantel-Haenszel (CMH) method with continuity correction for adjusted stratified variables was used to estimate the treatment effect in the MAKE90 endpoint. For MAKE90 endpoint missingness due to partial or complete missingness of individual components, missingness of KRT initiation or death was classified as non-events, and missingness of eGFR was handled by multiple imputation from a mixed model repeated measures (MMRM), assuming missing at random by treatment group, and then dichotomized into a binary variable. The MMRM model included baseline, CKD stage, type of surgery, visit, treatment group, and the interaction of treatment group and visit as fixed effects, and participant as a random effect, using all available data. Rubin's rule was used to combine the results to produce multiple imputed point estimates and standard errors. If the distribution of the CMH test statistic deviated strongly from normality, the Wilson-Hilferty transformation was applied before combining using Rubin's rule. The p-value and two-sided 95% confidence interval (CI) for the treatment difference in MAKE90 were reported.

[0570] A sensitivity analysis was conducted to evaluate the robustness of the results to the missing data estimation method. Based on a logistic regression model, multiple imputation of MAKE90 missing data was performed by treatment group. The logistic model included CKD stage, type of surgery, visit, treatment group, and the interaction of treatment group and visit as covariates. The CMH test was applied in the same manner as in the primary analysis together with Rubin's rule. If the CMH test statistic deviated substantially from the normality assumption, the Wilson-Hilferty transformation was applied.

[0571] A second sensitivity analysis was conducted based on multiple imputation from a jump-to-reference (J2R) model. For participants who discontinued the study without any further follow-up data, any missing values after discontinuation were imputed under the assumption that their outcomes would be similar to those in the placebo group with similar baseline characteristics. The CMH test was conducted in a similar manner to the primary analysis.

[0572] In addition, the individual MAKE 90 components were analyzed. The proportion of participants with an eGFR (using the CKD-EPI formula with sCysC) decrease of ≥25% from baseline by day 90 after CPB, or KRT initiation by day 90 after CPB, or death for any reason by day 90 after CPB was summarized by treatment group and visit. Point estimates of the treatment difference and the associated two-sided 95% CI were presented by visit using the CMH method (adjusted for stratifying factors).

[0573] In addition to the primary treatment policy estimates, other supplementary estimates using the ITT population or other populations (i.e., modified intention to treat [mITT], per protocol set [PPS], and postoperative set [POS]) were defined to assess the robustness of the primary estimate effect. Details are provided in the SAP.

[0574] The secondary efficacy analysis was based on the ITT analysis set. A sequential testing procedure for the key secondary endpoints was performed in the following order:

[0575] A. No CSA-AKI at 90 days after CPB, which was defined as no AKI within the first 7 days after CPB or recovery of AKI by day 90 after CPB (stage 0);

[0576] B. No severe CSA-AKI (KDIGO stage 2 or 3) based on the highest sCr observed within 7 days after CPB;

[0577] C. No any severe AKI (RIFLE injury or failure criteria) based on the highest sCr observed within 30 days after CPB;

[0578] D. No any severe AKI (KDIGO stage 2 or 3) based on the highest sCr observed within 30 days after CPB; and

[0579] E. No any RIFLE failure criteria based on the highest sCr observed within 30 days after CPB.

[0580] F. All-cause mortality from randomization to day 90 after CPB

[0581] The highest sCr observed was from central laboratory samples collected at specific study visits from daily local laboratory sCr results at any time during the first 30-day period. The baseline sCr used to define AKI was based on the mean of the sCr collected during screening and on day 1 before the study intervention was administered. Specifically, when the null hypothesis for the primary endpoint was rejected, the key secondary endpoints were tested at the same significance level as the primary endpoint, and the sequential testing was terminated when any null hypothesis failed to be rejected.

[0582] The analysis of the key secondary endpoints was the same as the primary analysis. The observed proportions of participants meeting each key secondary endpoint were summarized by treatment group.

[0583] To estimate the treatment effect in the key secondary endpoints, if applicable, missing data due to early withdrawals and all other events were imputed by the last observation carried forward (LOCF) method, otherwise the missing was classified as not reaching the endpoint. The CMH method adjusted for stratification factors was used to estimate the point estimate and the associated two-sided 95% CI.

[0584] If the test of the primary endpoint shows statistical significance, examine the association between each of the key secondary endpoints 2 to 5 above and the following clinical outcomes: death, initiation of KRT, readmission, duration of KRT (days), duration of ICU stay (days), duration of ventilation (days), and duration of hospitalization (days).

[0585] For binary clinical outcomes including death, initiation of KRT, and readmission, provide a 2×2 contingency table of clinical outcomes and key secondary endpoints by treatment group and overall. Perform a chi-square test to test the correlation between the two variables.

[0586] For continuous clinical outcomes, provide summary statistics by key secondary endpoint category, by treatment group, and overall. Apply linear regression with the key secondary endpoint and treatment group as covariates.

[0587] Similar to the primary endpoint MAKE90 determined based on the CKD-EPI formula using sCysC, MAKE90 is also determined based on the CKD-EPI formula using sCr. In addition, the MAKE30 and MAKE60 endpoints are determined similarly. The proportion of participants experiencing MAKE at days 30, 60, and 90 after CPB is summarized by treatment group and visit. Point estimates of treatment differences and the associated two-sided 95% CIs are presented using the CMH method (adjusted for stratifying factors).

[0588] In addition, analyze the individual MAKE components. The proportion of participants with a ≥25% decrease in eGFR from baseline at days 30, 60, and 90 after CPB, or the proportion of participants initiating KRT at days 30, 60, and 90 after CPB, or the proportion of participants dying for any reason at days 30, 60, and 90 after CPB is summarized by treatment group and visit. Point estimates of treatment differences and the associated two-sided 95% CIs are presented by visit using the CMH method (adjusted for stratifying factors).

[0589] Exploratory additional analyses may be conducted to examine the treatment effects of each individual component of MAKE at days 30, 60, and 90 after CPB.

[0590] The proportion of participants who experience KRT or death at days 30, 60, and 90 after CPB is summarized by treatment group. Point estimates and the associated two-sided 95% CIs are provided using the CMH method (adjusted for stratifying factors).

[0591] The proportion of participants with the highest stage of CSA-AKI observed within the first 3 days and first 7 days after CPB using the improved KDIGO criteria is summarized by treatment group.

[0592] The proportions of participants without CSA-AKI and without any AKI were summarized by treatment group and visit at pre-specified visits. The CMH method (adjusted for stratifying factors) was used to estimate the point estimates and associated two-sided 95% CIs.

[0593] Among participants who experienced CSA-AKI within 7 days after CPB, the proportions of participants with AKI recovery (complete or partial), improved AKI, stable AKI, or progressive AKI at 15, 30, 60, and 90 days after CPB were summarized by treatment group and visit. The CMH method adjusted for stratifying factors (if appropriate) was used to estimate the point estimates and associated two-sided 95% CIs.

[0594] The durations (days) of index hospital and ICU stays were calculated based on the discharge date minus the admission date for each participant, where the index hospital and ICU stays refer to the admission due to CPB surgery. For patients using a ventilator, the duration (days) of ventilator use was calculated based on the date of weaning from the ventilator minus the date of starting the ventilator. For patients undergoing KRT, the duration (days) of KRT was calculated based on the last date of KRT minus the start date of KRT.

[0595] Descriptive statistics were used to summarize the durations for each treatment group. It included the number of observations, mean, standard deviation, median, minimum, maximum, interquartile range (IQR), first quartile, and third quartile values in each treatment group.

[0596] The readmission rates (all-cause or AKI-related) up to 30 and 90 days after CPB were summarized by treatment group and visit. The CMH method adjusted for stratifying factors (if appropriate) was used to estimate the point estimates and associated two-sided 95% CIs.

[0597] The following quality of life assessments were summarized by treatment group using descriptive statistics of the observations and the change from baseline at baseline and each post-baseline time point: FACIT-Fatigue, EQ-5D-5L, and KDQOL-36.

[0598] The changes from baseline for each treatment group from the MMRM analysis were also summarized; no formal treatment comparisons were made. The point estimates and two-sided 95% CIs of the mean differences of these measurement scores were presented.

[0599] The analysis of exploratory biomarker data was described in a separate analysis plan and will be summarized after the study is completed.

[0600] The multiple testing procedure includes testing for the primary endpoint and subsequent pre-specified hierarchical testing for key secondary endpoints. Statistical significance is evaluated in the order of the hypotheses. The secondary endpoints are tested in a fixed order only if the primary endpoint is statistically significant. The testing of the key secondary endpoints continues down the hierarchy only if the test for the previous secondary endpoint is statistically significant.

[0601] In the second interim analysis, i.e., when approximately 50% of the participants have completed the primary evaluation period, a re-estimation of the sample size is performed. The conditional test power based on the observed treatment effect is calculated to determine whether enrollment should continue to achieve the planned or increased sample size. The primary endpoint is tested in the final analysis when all enrolled participants have completed the primary evaluation period at a one-sided significance level of 0.025. If the test for the primary endpoint is statistically significant in the final analysis, the statistical significance of the key secondary endpoints is evaluated in a fixed order.

[0602] Under this pre-specified multiple testing procedure and hierarchical testing strategy, the overall type I error is controlled at the one-sided 0.025 level for multiplicity across the primary endpoint and key secondary endpoints. Other planned interim analyses at 30% sample size for early futility assessment have no risk of type I error inflation.

[0603] Safety is evaluated based on AEs, clinical laboratory findings, and vital sign findings. All safety analyses are conducted on the safety set.

[0604] The incidences of treatment-emergent adverse events (TEAEs), TEAEs leading to withdrawal from the study, and treatment-emergent serious adverse events (TESAEs) are summarized by treatment group. TEAEs are defined as those AEs that represent an episode or a worsening in the severity of an existing event from the start of study intervention administration through 90 days after the study intervention dose. All AEs are coded using the Medical Dictionary for Regulatory Activities (MedDRA), version 24.1 or higher, and are summarized by system organ class (SOC) and preferred term overall, by severity, and by relationship to the study intervention. A detailed list of TEAEs, TESAEs, related TEAEs, and TEAEs leading to withdrawal from the study is provided by participant. Participants with multiple AEs within a category (e.g., overall, SOC, preferred term) are counted once in that category. For the severity tables, the most severe event for a participant within a category is counted. AESIs (such as meningococcal infection) are analyzed similarly.

[0605] Abnormal physical examination findings are classified as AEs and analyzed accordingly.

[0606] Vital signs are descriptively summarized by treatment group at baseline and post-baseline time points and by change from baseline.

[0607] Values observed in clinical chemistry, hematology, and urinalysis and changes from baseline were descriptively summarized by treatment group at baseline and at each post-baseline time point. For laboratory results that could be classified as normal, low, or high based on normal range values, shifts from baseline in the classifications were summarized across all study visits.

[0608] PK and PD analyses included all data in the PK analysis set and PD analysis set, respectively.

[0609] Graphs of mean serum ravulizumab concentration-time profiles were constructed. Graphs of serum concentration-time profiles for individual participants were also provided. Descriptive statistics of the serum concentration data were calculated at each sampling time (as appropriate).

[0610] The PD effect of ravulizumab was evaluated by assessing the absolute value, change from baseline, and percent change in serum free C5 concentration over time (as appropriate). Descriptive statistics of the PD data were calculated at each sampling time (as appropriate).

[0611] All anti-drug antibody (ADA) analyses were performed on the ADA analysis set (AAS).

[0612] The incidences of ADA response categories were summarized as absolute incidences (n) and percentages (%) of all participants in the ravulizumab group at Day 30 and Day 90. The antibody titers of confirmed antibody-positive samples and the presence of neutralizing antibodies were further evaluated. The maximum ADA titer levels of ADA-positive participants were listed and summarized as absolute incidences (n) and percentages (%) of all participants.

[0613] Associations between immunogenicity variables and effects on drug exposure, efficacy, and safety were explored.

[0614] Subgroup analyses of the primary endpoint and key secondary endpoints were performed on the following subsets of participants: (1) participants with different CKD stages at baseline, (2) participants who received different types of surgery during CPB, (3) participants in age groups 18 to 60, 61 to 75, and >75 years, (4) participants in weight groups ≥30 - 59 kg, 60 - 99 kg, ≥100 kg at baseline, (5) participants with the following levels of proteinuria (measured as albumin-to-creatinine ratio [ACR]) (KDIGO 2013) at baseline: <30 mg albumin / g creatinine, ≥30 to <300 mg albumin / g creatinine, ≥300 mg albumin / g creatinine, and (6) participants with and without diabetes.

[0615] Two interim analyses are planned to be conducted by the independent data monitoring committee (DMC) after approximately 30% (about 220 participants) and 50% (about 368 participants) of the randomized participants have completed the primary evaluation period (i.e., the visit at day 90 after CPB). The purpose of the first interim analysis is to evaluate futility for early stopping, and the second interim analysis is planned for sample size re - estimation.

[0616] For futility and sample size re - estimation assessments, conditional test power for the primary endpoint analysis is calculated at the interim analysis using the observed trends. If the conditional test power is less than 20% in the first interim analysis, the study is considered to be stopped early for futility. However, the futility criterion is non - binding. In other words, if the primary endpoint meets the pre - specified futility criterion at the first interim analysis, the study may continue without stopping for futility.

[0617] For sample size re - estimation at the second interim analysis, if the conditional test power falls within the promising region (0.5, 0.9), the study sample size is increased. This promising region is selected to ensure that the conventional analysis at the end of the study does not inflate the study type I error with the planned maximum sample size increase. To prevent potential unblinding of the interim analysis results in the sample size re - estimation procedure, a step - function is utilized to guide the sample size increase if the interim analysis results fall within the pre - specified promising region. Details of the interim analysis are recorded in the interim statistical analysis plan (iSAP) prior to the interim analysis.

[0618] 13. Exploratory Biomarkers

[0619] Unless otherwise specified, the tests detailed in Table 10 are conducted by the study central laboratory. Local laboratory results are required only in the event that central laboratory results cannot be used in a timely manner for eligibility, study intervention administration, and / or response assessment. If local samples are required, it is important to obtain samples for central analysis simultaneously. Additionally, if local laboratory results are used to make eligibility or study intervention decisions or response assessments, these results must be available in the participant's source documents. Serum creatinine tests conducted locally as a standard of care are reviewed for the first 30 days after CBP. The highest result observed is reported on the CRF. Additional laboratory tests may be conducted at any time during the study as determined necessary by the investigator or required by local regulations. Women of childbearing potential (WOCBP) are enrolled only after a negative pregnancy test result at screening. Additional pregnancy tests are conducted at the time points specified in the assessment schedule.

[0620] Table 10: Protocol - required laboratory assessments

[0621]

[0622] Table 10: Laboratory Assessments Required by the Protocol

[0623]

[0624] Abbreviations: ADA = anti-drug antibody; Ba = complement factor B; C5 = complement component 5; NAb = neutralizing antibody; PD = pharmacodynamics;

[0625] PK = pharmacokinetics; RBC = red blood cell; WBC = white blood cell; WOCBP = women of childbearing potential

[0626] 14. COVID-19 Vaccine Risk Assessment

[0627] Collect blood and urine samples for exploratory assessments related to ravulizumab or CSA-AKI and related diseases. These samples may also be used to further explore the development of assays related to the mechanism of action of ravulizumab, the course of the disease, and / or pathways related to the CSA-AKI disease state. The results of biomarker analysis may be reported in the CSR or later in a separate study summary.

[0628] Sequence Overview

[0629] There is currently no available information to evaluate the safety and efficacy of COVID-19 vaccines in participants being treated with ravulizumab. Based on the mechanism of action of ravulizumab, it is unlikely that the administration of ravulizumab will impair the immune response to COVID-19 vaccines (and thus the efficacy of vaccination). It is also unlikely that COVID-19 vaccination will affect the mechanism of action of ravulizumab.

[0630] Vaccination may further activate complement. Therefore, participants with complement-mediated diseases may experience increased signs and symptoms of their underlying disease. Therefore, participants' disease symptoms should be closely monitored after the recommended vaccination. Since vaccines can activate complement, if possible, consider vaccination shortly after administration when the potential complement-mediated disease is clinically controlled and when the systemic C5 inhibitor concentration (and subsequent complement blockade) is relatively high. For recommendations related to COVID-19 vaccination, local and national guidelines should be consulted.

[0631] Potential risks identified and mitigation measures taken according to the COVID-19 vaccination rollout are provided in Table 11.

[0632] Table 11: Potential Operational Risks and Mitigation Measures Due to COVID-19 Vaccines

[0633]

[0634] Abbreviations: COVID-19 = Coronavirus Disease 2019; CRF = Case Report Form.

[0635] ​

[0636]

[0637]

[0638]

[0639]

[0640]

Claims

1. A method for preparing a human patient with chronic kidney disease (CKD) for cardiac surgery using cardiopulmonary bypass (CPB), wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

2. A method for inhibiting terminal complement activation in a human patient with CKD before cardiac surgery using CPB, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

3. A method for treating a human patient with CKD before cardiac surgery using CPB, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once before the surgery at the following doses: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

4. A method for preventing or reducing cardiac surgery-associated acute kidney injury (CSA-AKI) in a human patient with CKD, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or an antigen-binding fragment thereof wherein the anti-C5 antibody or antigen-binding fragment thereof comprises the CDR1, CDR2, and CDR3 heavy chain sequences shown in SEQ ID NOs: 19, 18, and 3, respectively, and the CDR1, CDR2, and CDR3 light chain sequences shown in SEQ ID NOs: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once at the following doses prior to cardiac surgery using CPB: a) 2700 mg for patients weighing ≥30 kg to <40 kg; b) 3000 mg for patients weighing ≥40 kg to <60 kg; c) 3300 mg for patients weighing ≥60 kg to <100 kg; or d) 3600 mg for patients weighing ≥100 kg.

5. A method of preventing or reducing one or more major adverse kidney events (MAKE) in a human patient with CKD, wherein the method comprises administering to the patient an effective amount of an anti-C5 antibody or antigen-binding fragment thereof, wherein the anti-C5 antibody or antigen-binding fragment thereof comprises the CDR1, CDR2, and CDR3 heavy chain sequences shown in SEQ ID NOs: 19, 18, and 3, respectively, and the CDR1, CDR2, and CDR3 light chain sequences shown in SEQ ID NOs: 4, 5, and 6, respectively, and wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once at the following doses prior to cardiac surgery using CPB: a) 2700 mg for patients weighing ≥30 kg to <40 kg; b) 3000 mg for patients weighing ≥40 kg to <60 kg; c) 3300 mg for patients weighing ≥60 kg to <100 kg; or d) 3600 mg for patients weighing ≥100 kg.

6. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered at least one calendar day prior to the CPB.

7. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered one to seven calendar days prior to the CPB.

8. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof further comprises a variant human Fc constant region that binds to the human neonatal Fc receptor (FcRn), wherein the variant human Fc constant region comprises Met429Leu and Asn435Ser substitutions at residues corresponding to methionine 428 and asparagine 434 of the native human IgG Fc constant region, each numbered according to EU.

9. The method according to any one of the preceding claims, wherein the anti-C5 antibody comprises the heavy chain variable region shown in SEQ ID NO: 12 and the light chain variable region shown in SEQ ID NO:

8.

10. The method according to any one of the preceding claims, wherein the anti-C5 antibody further comprises the heavy chain constant region shown in SEQ ID NO:

13.

11. The method according to any one of the preceding claims, wherein the antibody comprises a heavy chain polypeptide comprising the amino acid sequence shown in SEQ ID NO: 14 and a light chain polypeptide comprising the amino acid sequence shown in SEQ ID NO:

11.

12. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof binds to human C5 with an affinity dissociation constant (K D ) in the range of 0.1 nM ≤ K D ≤ 1 nM (e.g., about 0.5 nM) at pH 7.4 and 25 °C.

13. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof binds to human C5 at pH 6.0 and 25 °C with a K D ≥ 10 nM (e.g., about 22 nM).

14. The method according to any one of claims 1 to 13, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight of ≥ 30 kg to < 40 kg at a dose of 2700 mg.

15. The method according to any one of claims 1 to 13, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight of ≥ 40 kg to < 60 kg at a dose of 3000 mg.

16. The method according to any one of claims 1 to 13, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight of ≥ 60 kg to < 100 kg at a dose of 3300 mg.

17. The method according to any one of claims 1 to 13, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered to a patient with a body weight of ≥ 100 kg at a dose of 3600 mg.

18. The method according to any one of the preceding claims, wherein the treatment maintains a serum trough concentration of the anti-C5 antibody of 175 μg / mL or greater.

19. The method according to any one of the preceding claims, wherein the treatment maintains a serum trough concentration of the anti-C5 antibody of 200 μg / mL or greater.

20. The method according to any one of the preceding claims, wherein the anti-C5 antibody or antigen-binding fragment thereof is formulated for intravenous administration.

21. The method according to any one of the preceding claims, wherein the cardiac surgery is selected from the group consisting of: coronary artery bypass grafting (CABG), valve replacement or repair, insertion of a pacemaker or implantable cardioverter defibrillator (ICD), maze surgery, maze surgery, heart transplantation, and insertion of a ventricular assist device (VAD) or total artificial heart (TAH), and transcatheter structural heart surgery.

22. The method according to any one of the preceding claims, wherein a single pre-operative body weight-based dose of the anti-C5 antibody or antigen-binding fragment thereof results in complete C5 inhibition for at least 18 days.

23. The method according to any one of the preceding claims, wherein the method prevents the need for renal replacement therapy (KRT).

24. The method according to any one of the preceding claims, wherein the method prevents or reduces CSA-AKI in the human patient with CKD.

25. The method according to any one of the preceding claims, wherein the human patient includes a patient with cardiac surgery-related acute kidney injury (CSA-AKI), wherein CSA-AKI is characterized by an increase in the following: a) Serum creatinine (sCr) or serum cystatin C (sCysC) ≥ 0.3 mg / dL within a 48-hour period within 7 days after CPB, and / or b) sCr or sCysC ≥ 1.5 times the baseline within 7 days after CPB or on days 15, 30, 60, or 90 after CPB.

26. The method according to any one of the preceding claims, wherein the human patient has no severe CSA-AKI based on the highest sCr observed within 7, 30, 45, 60 or 90 days after CPB, as evaluated by the improved Kidney Disease: Improving Global Outcomes (KDIGO) criteria.

27. The method according to any one of the preceding claims, wherein the human patient has no severe CSA-AKI based on the highest observed sCr within 7, 30, 45, 60 or 90 days after CPB, as evaluated by the improved "Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease" (RIFLE) criteria.

28. The method according to any one of claims 1 to 27, wherein the method results in stabilization of CSA-AKI within 7, 30, 45, 60 or 90 days after surgery, the stabilization being characterized by sCr ≥ 2.0 - < 3.0 × baseline.

29. The method according to any one of claims 1 to 28, wherein the method results in improvement from CSA-AKI within 7, 30, 45, 60 or 90 days after surgery, the improvement being characterized by sCr ≥ 1.5 - < 2.0 × baseline.

30. The method according to any one of claims 1 to 28, wherein the method results in partial recovery from CSA-AKI within 7, 30, 45, 60 or 90 days after surgery, the partial recovery being characterized by sCr ≥ 1.1 - < 1.5 × baseline.

31. The method according to any one of claims 1 to 28, wherein the method results in complete recovery from CSA-AKI within 7, 30, 45, 60 or 90 days after surgery, the complete recovery being characterized by sCr < 1.1 × baseline.

32. The method according to any one of the preceding claims, wherein the method prevents or reduces one or more MAKEs in the human patient with CKD.

33. The method according to any one of claims 5 to 32, wherein the one or more MAKEs are selected from the group consisting of: a) Sustained kidney dysfunction (SKD), which is defined as an estimated glomerular filtration rate (eGFR) after CPB that is > 25% lower than baseline, b) The occurrence of kidney replacement therapy (KRT) after CPB, and c) Death for any reason after CPB.

34. The method according to claim 33, wherein the decrease in eGFR is determined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula based on serum cystatin C (sCysC) or serum creatinine (sCr).

35. The method according to any one of the preceding claims, wherein the method results in a change in quality of life from baseline as evaluated via quality of life assessment.

36. The method according to claim 35, wherein the quality of life assessment is the Kidney Disease Quality of Life Short Form (KDQOL-36), the 5-dimension 5-level European Quality of Life Group (EQ-5D-5L), or the Functional Assessment of Chronic Illness Therapy (FACIT) Fatigue Scale.

37. The method according to any one of the preceding claims, wherein the method results in a shift of biomarkers associated with vasculitis (e.g., soluble tumor necrosis factor receptor 1 [TNF-R1 or sTNF-R1]), endothelial injury and / or activation (e.g., thrombomodulin), kidney injury (e.g., neutrophil gelatinase-associated lipocalin [NGAL]), inducers of cell cycle arrest (e.g., tissue inhibitor of metalloproteinase-2 [TIMP-2]), and / or complement proteins and complement activation pathway products (e.g., soluble C5b-9) towards normal levels.

38. A kit, comprising: (a) A dose of an anti-C5 antibody or an antigen-binding fragment thereof, the anti-C5 antibody or antigen-binding fragment thereof comprising CDR1, CDR2, and CDR3 heavy chain sequences as shown in SEQ ID NO: 19, 18, and 3, respectively, and CDR1, CDR2, and CDR3 light chain sequences as shown in SEQ ID NO: 4, 5, and 6, respectively; and (b) Instructions for using the anti-C5 antibody or antigen-binding fragment thereof in the method according to any one of the preceding claims.

39. An anti-C5 antibody or an antigen-binding fragment thereof for preparing a human patient with CKD for a cardiac surgery using cardiopulmonary bypass (CPB), wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg; b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg; c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or d) 3600 mg for patients with a body weight of ≥ 100 kg.

40. An anti-C5 antibody or an antigen-binding fragment thereof for inhibiting terminal complement activation in a human patient with CKD before a cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg; b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg; c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or d) 3600 mg for patients with a body weight of ≥ 100 kg.

41. An anti-C5 antibody or an antigen-binding fragment thereof for treating a human patient with chronic kidney disease before a cardiac surgery using CPB, wherein the anti-C5 antibody or antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg; b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg; c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or d) 3600 mg for patients with a body weight of ≥ 100 kg.

42. An anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof is used to prevent or reduce CSA-AKI in human patients with chronic kidney disease, and the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

43. An anti-C5 antibody or an antigen-binding fragment thereof, wherein the anti-C5 antibody or an antigen-binding fragment thereof is used to prevent or reduce one or more MAKEs in human patients with chronic kidney disease, and the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

44. Use of an anti-C5 antibody or an antigen-binding fragment thereof for preparing a human patient with CKD for a cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

45. Use of an anti-C5 antibody or an antigen-binding fragment thereof for inhibiting terminal complement activation in a human patient with CKD before a cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg.

46. Use of an anti-C5 antibody or an antigen-binding fragment thereof for treating a human patient with chronic kidney disease before a cardiac surgery using CPB, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once at the following doses before the surgery: a) 2700 mg for patients with a body weight of ≥30 kg to <40 kg; b) 3000 mg for patients with a body weight of ≥40 kg to <60 kg; c) 3300 mg for patients with a body weight of ≥60 kg to <100 kg; or d) 3600 mg for patients with a body weight of ≥100 kg. Use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing CSA-AKI in human patients with chronic kidney disease, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgery at the following doses: a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg; b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg; c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or d) 3600 mg for patients with a body weight of ≥ 100 kg.

48. Use of an anti-C5 antibody or an antigen-binding fragment thereof for preventing or reducing one or more MAKEs in human patients with chronic kidney disease, wherein the anti-C5 antibody or an antigen-binding fragment thereof is administered once before the surgery at the following doses: a) 2700 mg for patients with a body weight of ≥ 30 kg to < 40 kg; b) 3000 mg for patients with a body weight of ≥ 40 kg to < 60 kg; c) 3300 mg for patients with a body weight of ≥ 60 kg to < 100 kg; or d) 3600 mg for patients with a body weight of ≥ 100 kg.

49. The anti-C5 antibody or an antigen-binding fragment thereof according to any one of claims 39 to 44, wherein the anti-C5 antibody or an antigen-binding fragment thereof is ravulizumab 50. Use according to any one of claims 45 to 49, wherein the anti-C5 antibody or antigen-binding fragment thereof is ravulizumab

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