(EXTRACTED FROM WIPO PAGE)
ANTI-PROPERDIN ANTIBODIES AND PREPARATION THEREOF
Field of the invention
The present invention relates to an antibody or antigen-binding portion thereof that can bind to properdin (factor P). The antibody according to the present invention is further used in the preparation of a drug for treating diseases through inhibition of alternative complement pathway.
Background of the invention
Scientists have strived for decades to develop drugs to treat complement-mediated diseases. By the end of the 20th century, many anti-complement agents had shown promise in vitro and in animal models, but few drug candidates had progressed to humans and those that did were not developed further. Among the preclinical molecules being tested at that time were antibodies against complement components which blocked their function. For example, the blockade of function of C5 using the anti-mouse C5 and anti-human C5 monoclonal antibodies, was readily established using both, in vitro and in vivo animal disease models. By the early 21st century the humanised anti -human C5 monoclonal antibody, eculizumab, was progressing through clinical development and, in 2007, it was approved by the FDA for use in the rare but devastating disease, paroxysmal nocturnal haemoglobinuria (PNH). This clinical validation of anti-complement therapy was a landmark in complement drug discovery; this breakthrough, combined with ground-breaking data emerging from genome wide association studies (GWAS), which demonstrated key roles of complement in wide-spread disease, drove a renaissance in anti-complement drug discovery. This has brought us to the current day with many new drugs in this area that are progressing through late stage clinical development and numerous others in discovery or preclinical stages. (1)
However, high expectations raised by a drug candidate developed for ocular indications (i.e., the Factor D (FD)-targeting mAh, lampalizumab) failed to translate into meaningful clinical responses in phase III trials, indicating that individual challenges related to drug bioavailability or efficacy remain to be addressed. The recent FDA approval of a long- acting version of eculizumab (ALXN1210/ravulizumab, Ultomiris, Alexion), which features an extended plasma residence and only requires administration every 8 weeks instead of biweekly, is an important step in improving patient management but cannot be considered a bona fide new drug entry in the field. With the current clinical availability of only a single complement specific drug, which evidently cannot cater for all complement-associated clinical indications, the need for disease- tailored therapeutic approaches is becoming ever more urgent. (2)
However, it is to be noted that, the development of drugs targeting complement pathway is associated with a number of challenges, including the sheer number of proteins that one has to choose from, the quantity of circulating or membrane bound proteins of each such target, the natural central role of complement in fighting infection and the safety impact of regulating it too strongly, and the identification of an appropriate disease, or drug indication. In a number of diseases, complement plays a driving role in pathogenesis, whereas in others, complement is an ‘exacerbator' of disease, inducing increased pathology initiated by a different disease trigger, thus driving inflammation and tissue damage.
Nevertheless, the number of potential drugs in the complement system is expanding as the role of complement beyond lysis and in cross-talk with other biological systems, such as coagulation, is becoming clearer. There are drugs in development which target each of the three pathways in the complement system and these drugs include small molecules, peptides, biologies, antibodies and DNA-based therapeutics.
Due to the cascade nature of complement pathway and the large number of proteins - both soluble and membrane bound - that it is comprising of, selecting distinct points of intervention may result in different therapeutic effects. In most cases of trigger, the complement pathway is activated by foreign or altered surfaces. In the classical pathway, recognition of immune complexes (and other non -immunoglobulin moieties) by C1q activates the associated serine proteases, C1r and C1s, which cleave the plasma proteins C2 and C4 to form a C3 convertase complex (C4b2a) on the activating surface. The same result is achieved when pattern recognition proteins of the lectin pathway (mannose-binding lectin [MBL], ficolins, collectins) bind to carbohydrate patterns on the pathogen surface and induce MBL-associated serine proteases to cleave C2/C4. The alternative pathway, through an interplay with the proteases, factor B and D (FB, FD), and surface-bound C3b, forms another type of C3 convertase. In all three complement pathways, the point of convergence is the generation of one or the other C3 convertases that activate C3, resulting in at least two significant events on the affected cell surface. One is the deposition of C3b on the target surface (making it a candidate for opsonisation by macrophages) and the simultaneous release of anaphylatoxin,
C3a. The other is the formation of C3bBb (C3 convertase) and its stabilization by properdin for the assembly of C5 convertases, which cleave C5. The alternative pathway is the only pathway that remains constitutively active providing a constant minimal background activity ready to amplify with the availability of the right trigger. Whereas the released anaphylatoxin, C5a, is amongst the strongest chemoattractants and pro -inflammatory modulators, working primarily via binding to C5a receptor 1 (C5aRl), the C5b fragment can induce the assembly of membrane attack complex (MAC) that damage or induce lysis of the attacked cells. (1)
More than 20, therapeutic agents targeting distinct components and effector pathways of the complement cascade are now in clinical development for various indications. (2)
The amplification loop of the alternative pathway is a major driving force behind complement activation and often determines the onset of C5 convertase formation, thereby initiating subsequent C5 cleavage and terminal pathway activation. Even in diseases where pathological mechanisms are mediated by the lectin or classical pathways, blockade of the alternative pathway may provide therapeutic benefit due to the reduction of the effect generated through the amplification loop. Therefore, a designed specific intervention of only the amplification loop is considered an attractive proposition in drug development as this would allow the lectin and classical pathways to remain at least partly functional to fight infections; while the blocking of the alternative pathway would control collateral damage to normal tissue.
Within the amplification loop there are multiple druggable targets, e.g., C3 (or C3b), FB, FD and FP (properdin), and all have been targeted in drug development. (1)
Despite the progression of drug leads to late- stage clinical development, even more than a decade after the launch of eculizumab, the complement drug market still lacks any new approved therapeutics directed against alternate targets in the cascade. Emerging cases of insufficient response to anti-C5 therapy and the appreciation that multiple triggers and complex genetic traits may convolute a patient's basal complement activity in yet- poorly defined ways, point to the need for more comprehensive patient stratification and robust monitoring during anti-complement treatment of the diseases currently treated with eculizumab.
Though the approval of eculizumab drastically changed the landscape of PNH by introducing the first aetiological therapy for these patients, unmet clinical needs have emerged, including the genetically driven refractory phenotype to anti-C5 in certain patients, the residual
haemolysis of C3- opsonized PNH cells in extravascular compartments, and the pharmacokinetic/ Pharmacodynamics (PK/PD) breakthrough haemolysis observed in certain cases that evoke strong complement activation (that is, acute infections), irrespective of drug dosing levels. (2).
It is important to note that anti-C5 therapy is associated with the risk of life-threatening and fatal meningococcal infections which may become rapidly life-threatening or fatal if not recognized and treated early. (3)
It is therefore quite conceivable that in most of the complement mediated disease situations a complete inhibition of MAC formation originating from all complement pathways is not essential, and turning down, rather than turning off, complement is likely to be sufficient to confer therapeutic effect while permitting sufficient portion of complement activity remaining to protect from critical infections. The aim of such treatments would be to reverse dysregulation and restore homeostasis. In this context, the amplification loop represents an excellent target. Reducing cycling through the amplification loop by increasing loop regulation or reducing availability of convertase could enable fine-tuning of therapy to ameliorate pathology while retaining the protective roles of complement in immune defence. This will be a significant advantage for treating elderly and infection-vulnerable individuals in the community. Several AP-specific drugs are in phase 2 development, including inhibitors of FB and FD. Other drugs which have modulatory properties are on the horizon; delivery of functional domains of regulators such as FH can directly modulate the convertase enzymes, as in the preclinical molecule AMY201 (Amyndas), a truncated, recombinant form of FH engineered to bind with superior efficacy to target surfaces. Finally, it may be possible to block natural modifiers of complement; properdin stabilises the AP convertase enzymes and MASP3 activates FD, interference at these levels using drugs such as CLG561 (anti-properdin, Novartis) or OMS906 (preclinical anti-MASP3, Omeros) may nudge the complement system towards restored homeostasis. (4)
The present invention is related to antibodies targeting properdin (factor P) to inhibit alternative pathway.
Monoclonal antibodies to properdin are known in the art and have been described, for example, in WO 2006131874, WO 2009110918, WO 201109494, WO 2013006449 and WO 2018140956. Various antibodies have been developed which bind activated properdin, but to
the best of our knowledge, none has been approved yet. There is one antibody CLG561 targeting properdin, which is in early clinical stage where it has been evaluated in combination with an anti-C5 antibody. (5)
Thus, there is still an unmet need to effectively regulate properdin activity and thus control alternative complement pathway. Therefore, present invention provides an anti-properdin antibody which can be developed to treat related diseases.
Summary of the invention
The present invention provides an antibody or antigen-binding portion thereof that can bind to properdin (factor P). The antibody of the current invention leads to selective inhibition of alternative complement pathway while allowing the classical and lectin pathways to continue. Further, the antibody of the present invention may have modified or reduced binding to FcγRs to minimize its ADCC activity. The present invention provide an antibody that comprises an amino acid sequence to minimise its CDC activity. The antibody according to the present invention has higher FcRn binding affinity and therefore the antibody according to the present invention may have long circulating half-life in the body of the patient and it can be given at a reduced dosing frequency. The antibody according to the present invention can further be used in the preparation of a drug for treating diseases through inhibition of alternative complement pathway.
Brief description of figures
Figure 1 demonstrates the dose-dependent binding of anti-properdin binders to the native purified human properdin. Tested anti-human properdin mAbs of the present invention showed significant binding to native antigen.
Figures 2a & 2b demonstrate that the anti-human properdin mAbs of the current invention inhibit the human alternate complement mediated rabbit red blood cells (RBCs) lysis. This lysis was almost completely inhibited by each of the tested anti-properdin mAbs. The isotype control mAh was used as the negative control and showed only negligible inhibition of lysis.
Figure 3a demonstrates the cross-reactivity of anti-properdin mAbs with monkey properdin in its serum. All tested humanized anti-human properdin mAbs of the current invention were able to inhibit lysis of rabbit RBCs mediated by monkey alternate complement system from monkey serum.
Figure 3b demonstrates the haemolysis inhibition activity of anti-properdin mAb P15 (GLS) in six different monkeys. P15 (GLS) was able to inhibit 85-95% lysis of rabbit RBCs mediated by monkey serum in different monkeys.
Figure 4 demonstrates the dose-dependent inhibition of LPS-induced complement activation by all the tested mAbs of the current invention. All tested mAbs effectively inhibited complement activation mediated by normal human serum (NHS) at both concentrations tested. All tested mAbs showed significant inhibition of MAC formation.
Figure 5 demonstrates the inhibition of human serum induced haemolysis of self- RBCs caused by CD55 and CD59 dysfunction using the anti-properdin mAbs of the current invention. Human RBCs are generally not lysed in the presence of autologous human serum. However, in the presence of anti-CD55 and anti-CD59 antibodies, the regulation of the complement pathway is disrupted leading to the haemolysis of self-RBCs by autologous serum. The said lysis was inhibited by each of the tested anti-properdin mAbs.
Figure 6 demonstrates the inhibition of human serum induced haemolysis of pronase treated self-RBC by all the tested anti properdin mAbs of the current invention.
Figure 7 demonstrates the decrease of intratracheal LPS instillation induced TNF-α production in mice by rabbit anti-mouse properdin mAb (surrogate antibody of the anti-properdin antibody of the current invention).
Figure 8 demonstrates the decrease of intratracheal LPS instillation induced IL-6 production in mice by rabbit anti-mouse properdin mAb (surrogate antibody of the anti-properdin antibody of the current invention).
Definitions
The term “antibody” as referred to herein includes whole antibodies and any antigen- binding fragments (i.e., “antigen-binding portion”) or single chains thereof. An “antibody” refers to a glycoprotein comprising at least two heavy (H) chains and two light (L) chains inter-connected by disulfide bonds, or an antigen-binding portion thereof. Each heavy chain is comprised of a heavy chain variable region (abbreviated herein as VH) and a heavy chain constant region. The heavy chain constant region is comprised of three domains, CH1, CH2 and CH3. Each light chain is comprised of a light chain variable region (abbreviated herein as VL) and a light chain constant region. The light chain constant region is comprised of one domain, CL- The VH and VL regions can be further subdivided into regions of hyper variability, termed complementarity determining regions (CDR), interspersed with regions that are more conserved, termed framework regions (FR). Each VH and VL is composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The variable regions of the heavy and light chains contain a binding domain that interacts with an antigen. The constant regions of the antibodies may mediate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells such as, NK cells, T cells, macrophages and dendritic cells etc.) and the first component (C1q) of the classical complement system.
The term “operatively linked” is intended to mean that an antibody gene is ligated into a vector such that transcriptional and translational control sequences within the vector serve their intended function of regulating the transcription and translation of the antibody gene.
The term “Ka” is the association rate of a particular antibody-antigen interaction, whereas the term “Kd” is the dissociation rate of a particular antibody-antigen interaction. The term “KD” is an affinity rate constant, which is obtained from the ratio of Kd to Ka. It can be measured by using surface plasma resonance method which is well known in the art.
The terms “monoclonal antibody” or “monoclonal antibody composition” as used herein refer to a preparation of antibody molecules of single molecular composition. A monoclonal antibody composition displays a single binding specificity and affinity for a particular epitope.
The term “bispecific antibody” refers to a homogeneous antibody population involved in the highly specific recognition and binding of two different antigenic determinants, or epitopes.
The term “recombinant antibody”, as used herein, includes all antibodies that are prepared, expressed, created or isolated by recombinant means. In certain embodiments, however, such recombinant antibodies can be obtained by in vitro mutagenesis and thus the amino acid sequences of the VH and VL regions of the recombinant antibodies as described herein are sequences that may not naturally exist within the human antibody germline repertoire in vivo.
The term “human antibody” includes antibodies having variable and constant regions (if present) derived from human immunoglobulin sequences, preferably human germline sequences.
The term “chimeric antibody and antigen-binding fragments thereof”, as used herein comprises portions from two or more different species (e.g., mouse and human). Chimeric antibodies can be produced with mouse variable regions of desired specificity fused to human constant domains (for example, as described in U.S. Patent No. 4,816,567). In this manner, non-human antibodies can be modified to make them more suitable for human clinical application (e.g., methods for treating or preventing a complement-mediated disorder in a subject).
The term “humanized” as used herein, forms of non-human (for example, murine) antibodies are chimeric antibodies that contain minimal sequence derived from non-human immunoglobulin. For the most part, humanized antibodies are human immunoglobulins (recipient antibody) in which residues from a hypervariable region of the recipient are replaced by residues from a hypervariable region of a non-human species (donor antibody) such as mouse, rat, rabbit or nonhuman primate having the desired specificity, affinity, and capacity. In some instances, Fv framework region (FR) residues of the human immunoglobulin are replaced by corresponding non-human residues. Furthermore, humanized antibodies may comprise residues that are not found in the recipient antibody or in the donor antibody. These modifications are made to further refine antibody performance. In general, the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable loops correspond to those of a non-human immunoglobulin and all or substantially all of the FR regions are those of a human immunoglobulin sequence. The humanized antibody optionally also will comprise at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin .
The term “pharmaceutical formulation” refers to preparations, which are in such form as to permit the biological activity of the active ingredients to be unequivocally effective. The term “pharmaceutical formulation” or “pharmaceutical composition” or “composition” can be used here interchangeably.
The term “excipient” refers to an agent that may be added to a formulation to stabilize the active drug substance in the formulated form to adjust and maintain osmolality and pH of the pharmaceutical preparations. Examples of commonly used excipients include, but are not limited to, sugars, polyols, amino acids, surfactants, and polymers. “Pharmaceutically acceptable” excipients are those which can reasonably be administered to a subject mammal to provide an effective dose of the active ingredient employed.
The term “treatment” or “therapeutics” as used herein, refers to any treatment of a disease in a mammal, particularly in a human. It includes: (a) preventing the disease from occurring in a subject which may be predisposed to the disease or at risk of acquiring the disease but has not yet been diagnosed as having it; (b) inhibiting the disease, i.e., arresting its development; and (c) relieving the disease, i.e., causing regression of the disease.
The terms “patient” and “subject” are used interchangeably and are used in their conventional sense to refer to a living organism suffering from or prone to a condition that can be prevented or treated by administration of a composition of the present invention, and includes both humans and non-human animals. Examples of subjects include, but are not limited to, humans, chimpanzees and other apes and monkey species; farm animals such as cattle, sheep, pigs, goats and horses; domestic mammals such as dogs and cats; laboratory animals including rodents such as mice, rats and guinea pigs; birds, including domestic, wild and game birds such as chickens, turkeys and other gallinaceous birds, ducks, geese, and the like. The term does not denote a particular age. Thus, adult, juvenile and new born individuals are of interest.
Table 1; Abbreviations of amino acid as used in the current application


Other abbreviations used in the current patent application:
ADCC: Antibody-dependent cellular cytotoxicity aHUS: atypical hemolytic uremic syndrome
CDC: Complement-dependent cytotoxicity
CDR: Complementarity determining region
CH: Constant region of heavy chain
CL: Constant region of light chain
DEPC: diethyl pyro carbonate
EDTA: Ethylene diamine tetra acetic acid
EGTA: Ethylene glycol-bis(β-aminoethyl ether) -N,N,N',N'-tetra acetic acid FcRn: Neonatal Fc receptor
FR: Framework region
HCVR: Heavy chain variable region
HC: Heavy chain
IPTG: Isopropyl β-D-1-thiogalactopyranoside
i.v.: Intravenous
Ka: Association constant
Kd: Dissociation constant
KD: Equilibrium dissociation constant
LCVR: Light chain variable region
LC: Light chain
LPS: Lipopolysaccharide
mAh: Monoclonal antibody
MAC: Membrane attack complex
NHS: Normal human serum
OD: Optical density
P20: Polysorbate 20
PBS: Phosphate buffer saline
PF buffer: Periplasmic fraction buffer
Pfx: Proof reading DNA polymerase, Pfx™ from Invitrogen
PNH: Paroxysmal nocturnal hemoglobinuria
RBC: Red blood cell
RPM: Revolutions per minute
RPMI: Roswell park memorial institute
sc: Subcutaneous
scFv: Single chain fragment variable
SEQ/ seq : Sequence
SPR: Surface plasmon resonance
TMA: Thrombotic micro angiopathy
TMB: 3, 3', 5, 5'-Tetramethylbenzidin
VH: Variable region of heavy chain
VL: Variable region of light chain
Embodiments of the invention
The disclosure of the present invention relates to novel anti-properdin antibodies that can be used for therapeutic purposes.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof of the present invention binds with high affinity to human properdin.
In one embodiment, the current invention provides an anti-properdin antibody or antigen binding portion thereof comprising:
(a) CDRH1 of the general formula (I): G-Y-X1a-X2a-X3a-X4a-X5a-X6a-X7a;
(b) CDRH2 of the general formula (II) : X1b-I-X2b-X3b-X4b-X5b-X6b-X7b;
(c) CDRH3 of the general formula (III): X1c-X2c-X3c-X4c-X5c-X6c-X7c-X8c-X9c-X10c-X11c-X12c- X13c-X14c;
(d) CDRL1 of the general formula (IV): X1d-X2d-X3d-X4d-X5d-X6d-X7d-X8d-X9d-X10d-X11d- X12d-X13d-X14d-X15d-X16d-X17d;
(e) CDRL2 of the general formula (V): X1e-X2e-X3e-X4e-X5e-X6e-X7e and
(f) CDRL3 of the general formula (VI): X1f-X2f-X3f-X4f-X5f-X6f-X7f-X8f-X9f-X10fX11f wherein,
X1a is an amino acid selected from serine and threonine;
X2a is an amino acid selected from phenylalanine and isoleucine;
X3a is an amino acid selected from threonine and alanine;
X4a is an amino acid selected from aspartic acid, serine and histidine;
X5a is an amino acid selected from tyrosine, asparagine, glycine and threonine;
Each of X6a and X7a may be present or absent and when present, is tyrosine amino acid;
X1b is an amino acid selected from valine, leucine, tyrosine and glutamic acid;
X2b is an amino acid selected from serine, asparagine and aspartic acid;
X3b is an amino acid selected from threonine, proline and tyrosine;
X4b is an amino acid selected from tyrosine, glycine, aspartic acid and serine;
X5b is an amino acid selected from tyrosine, threonine, glycine and alanine;
X6b is an amino acid selected from glycine, aspartic acid and threonine;
X7b is an amino acid selected from aspartic acid, tyrosine and asparagine;
X1c is an amino acid selected from aspartic acid, glutamic acid, alanine, and arginine;
X2cis an amino acid selected from leucine, aspartic acid, lysine and glycine;
X3c is an amino acid selected from aspartic acid, tyrosine, serine and leucine;
X4c is an amino acid selected from glycine, aspartic acid, arginine, tyrosine, leucine, serine and lysine;
X5c is an amino acid selected from tyrosine, arginine, aspartic acid, and glycine;
X6c is an amino acid selected from glutamic acid, serine, phenylalanine, tyrosine and asparagine;
X7c is an amino acid selected from serine, proline, aspartic acid, and phenylalanine or may be absent;
X8c is an amino acid selected from methionine, tryptophan, phenylalanine and valine or may be absent;
X9c is an amino acid selected from aspartic acid, and phenylalanine or may be absent;
Each of X10c and X11c may be present or absent and when present, is an amino acid independently selected from tyrosine and alanine;
Each of X12c, X13c and X14c may be present or absent and when present, is an amino acid independently selected from methionine, aspartic acid and tyrosine;
X1d is an amino acid selected from arginine, lysine, leucine, serine, tyrosine and glutamic acid;
X2d is an amino acid selected from proline, serine, alanine, leucine, glycine and glutamime;
X3d is an amino acid selected from serine, aspartic acid, arginine and tryptophan;
X4d is an amino acid selected from glutamine, glycine, serine and leucine;
X5d is an amino acid selected from aspartic acid, serine, threonine, proline and leucine;
X6d is an amino acid selected from isoleucine, valine, leucine, serine, asparagine, phenylalanine and glycine;
X7d is an amino acid selected from asparagine, leucine, glycine, proline, isoleucine, lysine and histidine;
X8d is an amino acid selected from asparagine, aspartic acid, threonine, glycine, arginine, glutamine and tyrosine;
X9d is an amino acid selected from tyrosine, isoleucine, tryptophan, asparagine, glycine, valine, histidine and serine;
X10d is an amino acid selected from leucine, asparagine, threonine, lysine, arginine and serine; X11d is an amino acid selected from serine, glycine, alanine, tyrosine, proline, aspartic acid and asparagine;
X12d is an may be absent;
X13dis an amino acid selected from threonine, serine, asparagine and lysine or may be absent;
Each of X14d, X15d, X16d and X17d may be present or absent and when present, is an amino acid independently selected from tyrosine, leucine, asparagine and alanine;
X1e is an amino acid selected from aspartic acid, tryptophan, tyrosine, leucine and alanine;
X2e is an amino acid selected from asparagine, alanine, threonine and valine;
X3e is an amino acid selected from asparagine, serine and threonine;
X4e is an amino acid selected from lysine, threonine, arginine and serine;
X5eis an amino acid selected from arginine and leucine;
X6e is an amino acid selected from phenylalanine, glutamic acid, histidine, aspartic acid and alanine;
X7eis an amino acid selected from serine and aspartic acid;
In one of the embodiments, CDR3 of the light chain (herein after referred as CDRL3) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1f-X2f-X3f-X4f-X5f-X6f-X7f-X8f-X9f-X10f-X11f wherein
X1f is an amino acid selected from histidine, glutamine, tryptophan, alanine, glycine and methionine;
X2f is an amino acid selected from glutamine, alanine and threonine;
X3f is an amino acid selected from tyrosine, glycine, leucine, arginine, tryptophan and glutamine;
X4f is an amino acid selected from leucine, asparagine, threonine, tyrosine, glutamine and aspartic acid;
X5f is an amino acid selected from serine, threonine, histidine, alanine and glycine;
X6f is an amino acid selected from serine, leucine, phenylalanine, threonine, isoleucine and tyrosine;
X7f is an amino acid selected from tyrosine, proline and leucine;
Xsf is an amino acid selected from threonine, proline, tyrosine, tryptophan and arginine;
X9f is an amino acid selected from threonine and glutamic acid or may be absent;
X10f is an amino acid selected from alanine and leucine or no amino acid and
X11f is valine amino acid or may be absent.
In one embodiment, the amino acid sequence of constant region of anti-properdin antibody comprises of the IgG1, IgG2, IgG3, IgG4, IgG2/G4 IgA, IgE, IgM or IgD constant region, preferably the IgG1 or IgG4.
In another embodiment, one or more anti-properdin antibodies of the present invention has modified or reduced or no ADCC and/or CDC activity. In one of the embodiments, the anti-properdin antibody or antigen binding portion thereof has reduced potential to cause the safety issue of ADCC and CDC.
In one of the embodiments, one or more anti-properdin antibodies of the present invention has reduced or no ADCP activity.
In one of the embodiments, the anti-properdin antibody or antigen binding portion thereof of the present invention has a KD of 10 -8 M or less, more preferably 10 -10 M or less for properdin antigen. KD value is a measurement of the binding affinity of the antibody towards its target antigen.
In one of the embodiments, the anti-properdin antibody or antigen binding portion thereof of the present invention cross-reacts with properdin from species other than human.
In one of the embodiments, the anti-properdin antibody or antigen binding portion thereof of the present invention has higher binding specificity towards human properdin.
In one of the embodiments, an anti-properdin antibody or antigen binding portion thereof of the present invention has an increased half-life in subject as compared to the anti-properdin antibody with conventional Fc fragment.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention blocks the function of properdin in mediating alternate complement pathway activation.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention prevents the binding of properdin to target cells.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention can prevent the increased binding of C3b to the target cell surface.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention regulates the MAC formation on the target cell surface and thereby preventing the lysis of cells.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention can minimise the formation of anaphylatoxins, C3a and C5a.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention prevents the complement mediated lysis of the target cells.
In one embodiment, the anti-properdin antibody or antigen binding portion thereof according to the present invention has improved circulating half-life.
In another embodiment, the anti-properdin antibody or antigen binding portion is able to bind to the monkey properdin enabling ease of drug development by providing a relevant animal pharmacology and toxicology model.
In one of the embodiments, the present invention provides a composition comprising an anti-properdin antibody that specifically binds human properdin (factor P) and an acceptable carrier.
In another embodiment, the anti-properdin antibody or antigen binding portion thereof of the present invention can be used for the treatment of disease where activity of properdin is detrimental such as infections, various cancers, auto immune disorders and other disorders such as PNH, aHUS where complement activity is amplified.
Detailed description of the invention
In one embodiment, the anti-properdin antibody or antigen binding portion thereof of the present invention binds with high affinity to human properdin.
Amino acid sequences of the anti-properdin antibody
In one of the embodiments, CDR1 of the heavy chain (herein after referred as CDRH1) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of the general formula (I): G-Y-X1a-X2a-X3a-X4a-X5a-X6a-X7a wherein, X1a is an amino acid selected from serine and threonine;
X2a is an amino acid selected from phenylalanine and isoleucine;
X3a is an amino acid selected from threonine and alanine;
X4a is an amino acid selected from aspartic acid, serine and histidine;
X5a is an amino acid selected from tyrosine, asparagine, glycine and threonine;
Each of X6a and X7a may be present or absent and when present, is tyrosine amino acid.
In one of the embodiments, CDR2 of the heavy chain (herein after referred as CDRH2) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1b-I-X2b-X3b-X4b-X5b-X6b-X7b wherein,
X1b is an amino acid selected from valine, leucine, tyrosine and glutamic acid;
X2b is an amino acid selected from serine, asparagine and aspartic acid;
X3b is an amino acid selected from threonine, proline and tyrosine;
X4b is an amino acid selected from tyrosine, glycine, aspartic acid and serine;
X5b is an amino acid selected from tyrosine, threonine, glycine and alanine;
X6b is an amino acid selected from glycine, aspartic acid and threonine;
X7b is an amino acid selected from aspartic acid, tyrosine and asparagine.
In one of the embodiments, CDR3 of the heavy chain (herein after referred as CDRH3) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1c-X2c-X3c-X4c-X5c-X6c-X7c-X8c-X9c-X10c-X11c-X12c-X13c-X14c wherein,
X1c is an amino acid selected from aspartic acid, glutamic acid, alanine, and arginine;
X2c is an amino acid selected from leucine, aspartic acid, lysine and glycine;
X3c is an amino acid selected from aspartic acid, tyrosine, serine and leucine;
X4c is an amino acid selected from glycine, aspartic acid, arginine, tyrosine, leucine, serine and lysine;
X5c is an amino acid selected from tyrosine, arginine, aspartic acid, and glycine;
X6c is an amino acid selected from glutamic acid, serine, phenylalanine, tyrosine and asparagine;
X7c is an amino acid selected from serine, proline, aspartic acid, and phenylalanine or no amino acid;
X8c is an amino acid selected from methionine, tryptophan, phenylalanine and valine or no amino acid;
X9c is an amino acid selected from aspartic acid, and phenylalanine or no amino acid;
Each of X10c and X11c is present or absent and when present, is an amino acid independently selected from tyrosine and alanine;
Each of X12c, X13c and X14c is present or absent and when present, is an amino acid independently selected from methionine, aspartic acid and tyrosine.
In one of the embodiments, CDR1 of the light chain (herein after referred as CDRL1) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1d-X2d-X3d-X4d-X5d-X6d-X7d-X8d-X9d-X10d-X11d-X12d- X13d-X14d-X15d-X16d-X17d wherein,
X1d is an amino acid selected from arginine, lysine, leucine, serine, tyrosine and glutamic acid;
X2dis an amino acid selected from proline, serine, alanine, leucine, glycine and glutamime;
X3dis an amino acid selected from serine, aspartic acid, arginine and tryptophan;
X4dis an amino acid selected from glutamine, glycine, serine and leucine;
X5dis an amino acid selected from aspartic acid, serine, threonine, proline and leucine;
X6d is an amino acid selected from isoleucine, valine, leucine, serine, asparagine, phenylalanine and glycine;
X7d is an amino acid selected from asparagine, leucine, glycine, proline, isoleucine, lysine and histidine;
X8d is an amino acid selected from asparagine, aspartic acid, threonine, glycine, arginine, glutamine and tyrosine;
X9d is an amino acid selected from tyrosine, isoleucine, tryptophan, asparagine, glycine, valine, histidine and serine;
X10dis an amino acid selected from leucine, asparagine, threonine, lysine, arginine and serine; X11d is an amino acid selected from serine, glycine, alanine, tyrosine, proline, aspartic acid and asparagine;
X12d is an amino acid selected from lysine, valine, threonine, alanine and glutamine or no amino acid;
X13dis an amino acid selected from threonine, serine, asparagine and lysine or no amino acid;
Each of X14d, X15d, X16d and X17d is present or absent and when present, is an amino acid independently selected from tyrosine, leucine, asparagine and alanine. In one of the embodiments, CDR2 of the light chain (herein after referred as CDRL2) of the anti -properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1e-X2e-X3e-X4e-X5e-X6e-X7e wherein,
X1e is an amino acid selected from aspartic acid, tryptophan, tyrosine, leucine and alanine;
X2e is an amino acid selected from asparagine, alanine, threonine and valine;
X3e is an amino acid selected from asparagine, serine and threonine;
X4e is an amino acid selected from lysine, threonine, arginine and serine;
X5e is an amino acid selected from arginine and leucine;
X6e is an amino acid selected from phenylalanine, glutamic acid, histidine, aspartic acid and alanine;
X7e is an amino acid selected from serine and aspartic acid
In one of the embodiments, CDR3 of the light chain (herein after referred as CDRL3) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1f-X2f-X3f-X4f-X5f-X6f-X7f-X8f-X9f-X10f-X11f
X1f is an amino acid selected from histidine, glutamine, tryptophan, alanine, glycine and methionine;
X2f is an amino acid selected from glutamine, alanine and threonine;
X3f is an amino acid selected from tyrosine, glycine, leucine, arginine, tryptophan and glutamine;
X4f is an amino acid selected from leucine, asparagine, threonine, tyrosine, glutamine and aspartic acid;
X5f is an amino acid selected from serine, threonine, histidine, alanine and glycine;
X6f is an amino acid selected from serine, leucine, phenylalanine, threonine, isoleucine and tyrosine;
X7f is an amino acid selected from tyrosine, proline and leucine;
X8f is an amino acid selected from threonine, proline, tyrosine, tryptophan and arginine;
X9f is an amino acid selected from threonine and glutamic acid or no amino acid;
X10f is an amino acid selected from alanine and leucine or no amino acid;
X11f is valine amino acid or no amino acid
In one of the embodiments, CDRH1, CDRH2, CDRH3, CDRL1, CDRL2 and CDRL3 of anti- properdin antibody or antigen binding portion thereof of the present invention is selected from the amino acid sequences as given below in table 2.
Table 2: Amino acid sequences of CDR regions of anti-properdin antibodies


Accordingly, in another embodiment, the present invention provides an anti-properdin antibody, or antigen- binding portion thereof, comprising: a heavy chain variable region that comprises CDRH1, CDRH2, and CDRH3 sequences; and a light chain variable region that comprises CDRL1, CDRL2, and CDRL3 sequences, wherein:
(a) the heavy chain variable region CDRH3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 12, 13, 14, 15, 16, 17 and 18, and conservative modifications thereof; (b) light chain variable region CDRL3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 35, 36, 37, 38, 39, 40, 41, 42 and 43, and conservative modifications thereof.
In another preferred embodiment, the heavy chain variable region CDRH2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 6, 7, 8, 9, 10 and 11, and conservative modifications thereof; and light chain variable region CDRL2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33 and 34 and conservative modifications thereof.
In another preferred embodiment, heavy chain variable region CDRH1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4 and 5, and conservative modifications thereof; and the light chain variable region CDRL1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 and 29 and conservative modifications thereof.
In another embodiment, the present invention provides an antibody, or antigen-binding portion thereof comprising:
(a) a heavy chain variable region CDRH1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4 and 5;
(b) a heavy chain variable region CDRH2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 6, 7, 8, 9, 10 and 11;
(c) a heavy chain variable region CDRH3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 12, 13, 14, 15, 16, 17 andl8;
(d) a light chain variable region CDRL1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, and 29;
(e) a light chain variable region CDRL2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33, and 34; and
(f) a light chain variable region CDRL3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 35, 36, 37, 38, 39, 40, 41, 42 and 43; wherein the antibody specifically binds properdin, preferably human properdin.
In one of the embodiments, HCVR and LCVR of anti -properdin antibody or antigen binding portion thereof of the present invention is selected from the amino acid sequences as given in below table 3.
Table 3: Amino acid sequence of variable region of anti-properdin antibodies




In one of the embodiments, variable region of heavy chain of anti-properdin antibody or antigen binding portion thereof of the present invention comprising of CDRH1, CDRH2 and CDRH3 comprising amino acid sequences selected from below given table 4.
Table 4: CDR regions of HCVR sequences of anti-properdin antibodies

In one of the embodiments, variable region of light chain of anti-properdin antibody or antigen binding portion thereof of the present invention has combination of amino acid sequences of CDRL1, CDRL2 and CDRL3 selected from below given table 5.
Table 5: CDR regions of LCVR sequences of anti-properdin antibodies


Accordingly, the present invention provides an anti-properdin antibody, or antigen-binding portion thereof, comprising a heavy chain variable region and a light chain variable region, wherein:
(a) the heavy chain variable region comprises an amino acid sequence that is at least 80 % homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs: 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 and 55;
(b) the light chain variable region comprises an amino acid sequence that is at least 80 % homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs:
56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82 and 83.
Preferably, the present invention provides an anti-properdin antibody, or antigen-binding portion thereof, comprising a heavy chain variable region and a light chain variable region, wherein:
(a) the heavy chain variable region comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 and 55;
(b) the light chain variable region comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82 and 83.
A preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 7;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 13;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 20;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 31; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 37
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 7;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 13;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 21;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 32; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 38
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 7;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 13;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 21;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 32; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 36
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 2;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 8;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 14;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 20;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 31; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 36
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 3;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 9;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 15;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 22;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 33; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 39
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 4;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 10;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 16;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 23;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 34; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 40
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 5;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 11;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 18;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 29;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 30; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 41
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 5;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 11;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 17;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 29;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 30; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 41
Another preferred combination of CDRs of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1;
(b) a heavy chain variable region CDRH2 comprising SEQ ID NO: 6;
(c) a heavy chain variable region CDRH3 comprising SEQ ID NO: 12;
(d) a light chain variable region CDRL1 comprising SEQ ID NO: 19;
(e) a light chain variable region CDRL2 comprising SEQ ID NO: 30; and
(f) a light chain variable region CDRL3 comprising SEQ ID NO: 35
A preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 51; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 63
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:52; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 64
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:53; and (b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 65
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:54; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 66 Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 45; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 45; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 58
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 45; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 59
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 46; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 47; and (b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 60
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 48; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 61 Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 55; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 79
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 55; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 56
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 50; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 62
Another preferred combination of HCVR and LCVR of anti-properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 44; and
(b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 56
Yet another preferred combination of HCVR and LCVR of anti -properdin antibody or antigen-binding portion thereof according to the present invention comprises:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 49; and (b) a light chain variable region comprising the amino acid sequence of SEQ ID NO: 62
The antibodies according to the present invention can be full-length (for example, an IgG1 or lgG4 or IgG2 antibody) or may comprise only an antigen- binding portion (for example, a Fab, F(ab')2 or scFv fragment), and optionally be modified to effect functionality, e.g., to eliminate residual effector functions such as ADCC and CDC activity. Human antibodies can exist in two forms that are associated with hinge heterogeneity. In one form, an antibody comprises a stable four-chain construct of approximately 150-160 kDa in which the dimers are held together by an inter chain heavy chain disulfide bond. In a second form, the dimers are not linked via inter chain disulfide bonds and a molecule of about 75-80 kDa is formed composed of a covalently coupled light and heavy chain (half-antibody). The later form have been extremely difficult to separate, even after affinity purification. The frequency of appearance of the second form in various intact IgG isotypes is due to, but not limited to, structural differences associated with the hinge region isotype of the antibody. A single amino acid substitution in the hinge region of the human lgG4 hinge can significantly reduce the appearance of the second form (6) to levels typically observed using a human IgG1 hinge. Full-length antibodies comprising CDRs or variable regions of the present invention further comprise said single amino acid substitution (i.e., S228P) when it is developed in IgG4 form.
In a further embodiment, the antibody or antigen-binding portion thereof targeting properdin antigen according to the present invention is murine, chimeric, human, or humanized in
nature, preferably chimeric or human or humanized in nature, more preferably humanized in nature.
Preferably, the antibodies, preferably monoclonal antibodies of the present application, include “humanized” forms of the non-human (e.g., mouse) antibodies. Humanized or CDR-grafted mAbs are particularly useful as therapeutic agents for humans because they are not cleared from the circulation as rapidly as mouse antibodies and do not typically provoke an adverse immune reaction. Generally, a humanized antibody has one or more amino acid residues introduced into it from a non-human source. Methods of preparing humanized antibodies are generally well known in the art. For example, humanization can be essentially performed following the method of Winter and co-workers (7, 8 9 and 10), by substituting rodent frameworks or CDR sequences for the corresponding sequences of a human antibody. In some embodiments, humanized forms of non-human (e.g., mouse) antibodies are human antibodies (recipient antibody) in which the CDR region amino acid residues of the non-human antibody (e.g., mouse, rat, rabbit, or non-human primate antibody) having the desired specificity, affinity, and binding capacity are grafted onto the framework scaffold of a human antibody.
In some instances, one or more framework region amino acid residues of the human immunoglobulin are also replaced by corresponding amino acid residues of the non-human antibody (so called “back mutations”). In addition, phage display libraries can be used to vary amino acids at chosen positions within the antibody sequence. The properties of a humanized antibody are also affected by the choice of the human framework. Furthermore, humanized and chimerized antibodies can be modified to comprise residues that are not found in the recipient antibody or in the donor antibody in order to further improve antibody properties, such as, for example, affinity or effector function.
In another aspect, anti- properdin antibody according to the present invention has increased FcRn binding and increased half -life with modified or reduced or no ADCC and/or CDC activity. The anti- properdin antibody according to the present invention can be given to the subject with reduced dose and with a better dose regimen due to increased half-life as compared to known anti-properdin antibodies. In one of the embodiments, the anti-properdin antibody according to the present invention has amino acid sequences of constant region of IgG4 with P329G and/or M428L & N434S mutation. The constant region of anti-properdin antibody with mentioned all three mutations in IgG4 constant region is referred herein as IgG4 (GLS). In one of the aspects, anti- properdin antibody according to the present invention has reduced or no ADCP activity.
In one of the embodiments, the anti-properdin antibody according to the present invention is monoclonal antibody or bispecific antibody or polyclonal antibody, preferably monoclonal antibody.
Preparation of Antibodies
Antibodies according to the current invention are generated in mouse using standard methods well known in the art. The monoclonal antibodies of the present invention are converted into a humanized version for therapeutic use. The hybridoma cell lines discussed herein can readily be generated by those of ordinary skill in the art, given the guidance provided herein. Development of anti-properdin scFv phage display library was done after amplifying variable heavy (VH) and variable light (VL) genes from spleen RNA of the immunized mice. Both the VH and VL were joined with a peptide linker and cloned in phage display vector as described herein. Panning and screening for specific properdin binders were performed.
Further modifications in CDR and framework region
The present invention encompasses antibodies having one or more mutations in the CDR and / or variable region described herein, that may have similar functional characteristics and biological activity as described for antibodies provided herein. These mutations are known to the person skilled in the art and well within the scope of the current invention.
Further modifications in constant region
The present invention encompasses antibodies having one or more mutations in the hinge, CH2 or CH3 region that may be desirable, for example, to improve the circulating half-life of the antibody in subject, to completely abolish immune effector functions, to enhance effector functions, etc. These mutations are known to the person skilled in the art (11, 12).
Immunoconjugates and Bispecific antibodies
An immunoconjugate comprising an antibody of the present invention, or antigen-binding portion thereof, linked to another therapeutic agent, such as a cytotoxin or a radioactive isotope can also be developed. A bispecific molecule comprising an antibody, or antigen- binding portion thereof, of the present invention, linked to a second functional moiety having a different binding specificity than said antibody, or antigen-binding portion thereof can be developed. In one of the embodiments, the second functional moiety according to the present invention can bind to antigen selected from C3, C5, C5a, C5b, C3a, C3b, Factor B, Factor H and C1q. Methods of making bispecific antibodies are known in the art.
Nucleic acid molecules encoding anti-properdin antibodies, vectors and host cells
In one embodiment, the present invention provides nucleic acid molecules encoding the antibodies, or antigen -binding portions thereof as well as expression vectors comprising such nucleic acids and host cells comprising such expression vectors. In the present application, pZRCIII vector is used for the cloning and expression of anti-properdin antibodies of the present invention. pZRCIII vector is described in patent document WO 2012/046255A2. The host cell according to the present invention is prokaryotic or eukaryotic cell, preferably the host cell is an E. coli cell or a mammalian cell, such as a CHO cell.
Combination of anti-properdin of the present invention with other drugs
The present invention provides a combination comprising at least two or more antibodies or antigen binding portion thereof wherein at least one antibody or antigen binding portion thereof is anti-properdin antibody of the present invention. The combination according to the present invention may comprise second antibody or antigen binding portion thereof selected from anti-C3 antibody, anti-C5 antibody, anti-C5a antibody, anti-C5b antibody, anti-C3a antibody, anti-C3b antibody, anti-Factor B antibody, eculizumab, lampalizumab, ravulizumab, anti-properdin antibody in combination with anti-properdin antibody or antigen binding portion thereof the present invention. In another embodiment, the present invention provides a combination comprising of anti-properdin antibody or antigen binding portion(s) thereof and a peptide or a combination comprising anti-properdin antibody or antigen binding portion(s) thereof and a cytokine (preferably interleukin).
Pharmaceutical compositions
A pharmaceutical composition, containing one or a combination of monoclonal antibodies, or antigen-binding portion(s) thereof, of the present invention formulated together with a pharmaceutically acceptable carrier can be developed. Such compositions may include one or a combination of (e.g., two or more different) antibodies, or immunoconjugates or bispecific molecules of the invention. For example, a pharmaceutical composition of the invention can comprise a combination of antibodies (or immunoconjugates or bispecifics) that bind to different epitopes on the target antigen or to different epitopes on different target antigens or that have complementary activities.
Therapeutic Uses
The anti-properdin antibody or antigen-binding portion thereof or combination according to the current invention or bispecific antibodies or immunoconjugates according to the current invention can be used in therapeutic methods for the treatment of diseases mediated, directly or indirectly, by a component of the alternative complement pathway, and/or by a factor generated following activation of the alternative complement pathway.
In one embodiment of the present invention, the antibodies can be used to inhibit complement activation via the alternative pathway in vivo in subjects, including humans, suffering from disease such as, but not limited to, haematological disorders, chronic renal disorders, ocular inflammatory disorders, various cancers, autoimmune disease and inflammations.
In one embodiment of the present invention, the antibodies can be used to inhibit complement activation via the alternative pathway in vivo in subjects, including humans, suffering from disease or disorders such as, but not limited to, atypical haemolytic uraemic syndrome, haematopoietic stem cell (HSC) transplant- associated TMA (TA- TMA); pregnancy- related HELLP (haemolysis, elevated liver enzymes, low platelets) syndrome; and infection- related or medication- related TMAs, atherosclerosis, paroxysmal nocturnal hemoglobinuria, ischaemia-reperfusion (I/R) organ injury, age-related macular degeneration (AMD), geographic atrophy, ischemia-reperfusion following acute myocardial infarction, Henoch-Schonlein purpura nephritis, immune complex vasculitis, rheumatoid arthritis, arteritis, aneurysm, stroke, cardiomyopathy, sepsis- associated inflammation, haemodialysis- induced inflammation, C3 glomerulopathies, hemorrhagic shock, crush injury, multiple organ failure, hypovolemic shock and intestinal ischemia, transplant rejection, cardiac surgery, percutaneous transluminal coronary angioplasty (PTCA), spontaneous abortion, neuronal injury, Severe acute respiratory syndrome such as Coronavirus Disease 2019 (COVID-19), Middle East respiratory syndrome, viral pneumonia, spinal cord injury, myasthenia gravis, Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis, Guillain Barre syndrome, Parkinson's disease, Alzheimer's disease, acute respiratory distress syndrome,
asthma, chronic obstructive pulmonary disease, transfusion-related acute lung injury, acute lung injury, Goodpasture's disease, myocardial infarction, post-cardiopulmonary bypass inflammation, organ transplantation, periodontal disease, cardiopulmonary bypass, septic shock, transplant rejection, xeno transplantation, bum injury, systemic lupus erythematosus, membranous nephritis, Berger's disease, psoriasis, pemphigoid, dermatomyositis, anti-phospholipid syndrome, inflammatory bowel disease, hemodialysis, leukopheresis, plasmapheresis, heparin-induced extracorporeal membrane oxygenation LDL precipitation, extracorporeal membrane oxygenation, and macular degeneration. In vivo inhibition of alternative complement pathway activation is accomplished by administering the antibody to the subject.
The present invention is illustrated with the following non-limiting examples which should not be interpreted as limiting the scope of the invention in any way.
Examples
The following examples are put forth so as to provide to those of ordinary skills in the art with a disclosure and description of how the methods and antibodies claimed herein are performed. They are intended to purely exemplify only and are not intended to limit the scope of the disclosure. The other antibodies of the present invention can be developed using method as described in provided examples with suitable modifications. Such modifications are well known to the person skilled in the art.
Example 1: Immunization of mice with human properdin antigen for binder generation
Four healthy female BALB/c mice were used for the immunization study. Two of them were kept as placebo control in which only PBS was used for the immunization. The other two mice were immunized with human properdin. To demonstrate that the antigenic preparation was capable of inducing anti-properdin antibodies in a highly sensitive species, one rabbit was used as another control for immunization with the same antigen preparation so as to monitor the immune responses at various stages of the immunization processes. All animals were acclimatized for 2 days in the animal research facility before starting the immunization study. Commercially available human properdin protein (Quidel cat #A412) was used for immunization. Protein emulsion was made by mixing 400 μg of human properdin (in 400 μL PBS) and 400 μL of complete Freund's adjuvant (CFA) in a total volume of 800 μL in a siliconized 5 mL screw cap glass vial and vortexing the mixture for 10-15 minutes for
emulsion preparation. On day 0, a single dose of 100 μg emulsified protein in a volume of 200 μl (0.5 μg /μL) was injected subcutaneously at four sites on the back of each mouse.
Simultaneously, on day 0, 200 μg of protein emulsion in 400 μL (0.5 μg/ μL) was injected subcutaneously at 4 sites on the back of the rabbit.
Incomplete Freund's adjuvant (IFA) was used for the subsequent immunizations (boosters). Four boosters were given to the animals at an interval of 15 days after each immunization. Protein emulsion was made by mixing 200 μg properdin (in 400 μL PBS) and 400 μL of incomplete Freund's adjuvant (IFA). The mixture was vortexed in a siliconized 5 mL screw cap glass vial for 10-15 minutes for emulsion preparation. Each booster dose in mice was administered as single dose of 50 μg of protein emulsion in 200 μL. Booster dose in rabbit was given with 100 μg of protein in 400 μL. Health of the mice and rabbit were monitored daily. To test the antibody titers generated against human properdin antigen, blood was collected from rabbit 4-5 days prior to each booster. Serum was prepared from the blood and used in ELISA for determination of human properdin specific antibodies. Mice were sacrificed 15 days after the 4th booster dose and spleens were collected either for hybridoma generation or for preparing total RNA for phage library generation.
Example 2: Generation of anti-properdin binders after mouse immunization
Hybridoma generation
After fourth booster, the mice were sacrificed and the spleens were removed and chopped in to small pieces and passed through the cell strainer. Subsequently cells were resuspended in cold RPMI (Roswell Park Memorial Institute,) 1640 with 10 % FBS and centrifuged at 300g for 5 minutes. The cell pellet was resuspended in RPMI 1640 with 1 % FBS, filtered through a 50 μM syringe filter (BD #340603) and collected by centrifugation.
Polyethylene glycol based protocol was used for hybridoma fusions as described earlier (13, 14). Single cell suspensions were prepared from the spleen of immunized mice as explained above and used for fusion with Sp2/0 myeloma cells (ATCC). Sp2/0 and spleen cells (1:5 ratio) were fused using polyethylene glycol (M.W. 1500, Sigma). Post fusion, the cells were adjusted to a concentration of 0.5 x 106 cells/ mL in RPMI media (Sigma) supplemented with 10 % fetal bovine serum (Gibco) and 1x hypoxanthine-aminopterin-thymidine medium (HAT) (Sigma) for selection of hybridomas. Two hundred microliters of this cell suspension was added to each well of 96 well culture plates to generate minipools. After about ten days, culture supernatants were tested in ELISA for binding to purified human native properdin. Properdin reactive minipools were further expanded to 24 well and 6 well plates and T-flasks. The anti-properdin antibody samples from culture supernatants of selected minipools were tested for their binding to human properdin in ELISA.
Based on the results of human properdin reactivity in ELISA, eleven minipools were further short-listed to carry out single cell limiting dilution. For limiting dilution exercise, minipools were plated at a dilution of 1 cell/well in a 96 well culture plate in RPMI media supplemented with 10 % fetal bovine serum. Cells were allowed to grow further and expanded to 24 well and 6 well plates and T-flasks. Cell culture supernatants were tested again for their binding to human properdin in ELISA. 104 selected hybridoma clones were grown in serum free production media (BD Cell mAh Medium, Quantum Yield; BD Bioscience) and the culture supernatants were collected for antibody purification by Protein A affinity chromatography. These purified antibody candidates were further tested for their binding affinities in SPR based assay. Four hybridoma derived anti-properdin clones designated 103B2 (VH SEQ ID 54; VL SEQ ID 66), 124F9 (VH SEQ ID 53; VL SEQ ID 65), 137D4 (VH SEQ ID 52; VL SEQ ID 64) and 149F8 (VH SEQ ID 51; VL SEQ ID 63) were found to be the best performers from the whole group.
All the 4 clones were found to show good affinities in nM range for human properdin (table 6). Anti-properdin hybridoma mAbs 103B2, 124F9, 137D4 and 149F8 along with other anti- properdin binders coming from phage display library were further humanized and described in example 6.
Table 6: Kinetic rate constants of anti-properdin antibodies for human properdin

ScFv library generation by phage display method
For scFv library generation, the immunization protocol as described in example 1 was followed. Spleen from one sacrificed mouse was harvested 15 days after the 4th boost and transferred directly into 10 mL normal saline in a 50 mL polypropylene tube. Spleen was then weighed in diethyl pyrocarbonate (DEPC) treated 1.6 mL centrifuge tube. Total RNA was isolated using Trizol method as follows. Maintaining a temperature of 4 °C, the spleen was first minced with surgical blade in a petri dish until a homogenous suspension of spleen cells was formed. Two mL of trizol was added to 90-130 mg of spleen followed by mixing with pipetting and then by vortexing. The process of mincing was repeated until a homogenous mixture of spleen cells and trizol was formed. After that, chloroform (200 μL) was added to the homogenate, mixed and incubated at room temperature for 5 minutes. Homogenate was then centrifuged and supernatant was taken and equal amount of isopropyl alcohol was added for precipitation of RNA. RNA suspension was again centrifuged and pellet was washed with ice cold 70 % ethanol. After three washes, the pellet containing total RNA was resuspended in DEPC treated water and left overnight for dissolving at 4 °C.
mRNA was then isolated from total RNA as per the manufacturer's instructions (PolyATtract® mRNA Isolation Systems, Cat: Z5300, Promega). Isolated mRNA was used for cDNA preparation using Superscript™ III first-strand synthesis system (Cat No: 18080051, Invitrogen) following manufacturer's instructions.
Amplification of VH and VL: Primer sets (Mouse IgG Library Primer Set, Cat No: F2010, Progen) were used for amplifying variable regions of heavy and light chains from cDNA using PCR method following manufacturer's instructions. The amplified VH and VL fragments were analyzed on agarose gel and purified from the gel using QIAquick gel extraction kit (Qiagen cat no 28706).
Purified VH and VL were then cloned sequentially into phagemid vector one after another (pSEX81, Cat No: PR3005, Progen). In the first ligation, VH fragment and vector both were restriction digested with Ncol and Hindlll, purified from gel and ligated together. Ligation product was transformed into electrocompetent TG1 cells (Cat No: 60502-1, Lucigen). The VL fragment and VH fragment containing vector DNA was again restriction digested with Mlul and Notl restriction enzymes, purified and ligated together. The vector containing both the VH and VL fragments was transformed into electro competent cells as above. Transformed cells were plated on 2xYT agar plates containing ampicillin (100 μg / mL). A library of transformed cells produced thus was scrapped off from the agar plates and stored in 50 % glycerol at -80 °C until further use.
Example 3: scFv phage production from scFv library and purification thereof
Flasks containing 2xYT media with carbenicillin or ampicillin (100 μL/ mL) were inoculated with the cells from the glycerol stock of the above described library at the initial concentration of 0.06 OD600. Cultures were grown at 37 °C with shaking at 250 rpm till they reach an OD600 of upto ~0.4-0.6. Helper phages either, VCSM13 (Agilent, Cat no. 200251) or M13K07 (GE healthcare, Cat no. 27152401), were then added to the culture at a multiplicity of infection (MOI) of 20, and incubated first without shaking at 37 °C for 40 minutes, followed by another 40 minutes of incubation at 37 °C with shaking. Kanamycin was then added to the media and culture was grown overnight at 26 °C at 150 rpm. Overnight phage culture was centrifuged at 4000g and cell pellet was discarded. PEG (20 %)/NaCl (2.5M) solution at a ratio of 1:5 was added to the supernatant in order to precipitate the phages. Resuspended solution was incubated on ice for 20 minutes followed by centrifugation at 14,000g for 15 minutes at 4 °C. Supernatant was discarded and pellet was resuspended in 1 mL of sterile PBS with 0.01 % sodium azide. Phages were stored at 4 °C until further use.
Example 4: Biopanning of anti-properdin scFv expressing phages
ScFv library (1x1012 pfu) prepared in example 3 was screened for anti-properdin binders. First round of panning against properdin antigen was performed using antigen-immobilized, Immunotubes (Quidel, USA) that were prepared by incubating them with a 5 μg / mL properdin solution in carbonate buffer (0.1 M, pH 9.6) overnight at 4 °C. Immunotubes were washed 3 times with PBS and then incubated with phages in PBS for 2 h at 25 °C with constant rotation. The tubes were washed ten times with 4 mL PBS with tween20 (0.1 %) and subsequently 10 times with PBS. The bound phages were eluted with glycine-HCL pH 2.1 (0.1 M). The eluted phages were rescued by infection of TG1 E. coli cells, plated, and phages produced as described in example 3.
Second and third round of panning were performed on the properdin antigen coated immunotubes in such a manner that output phages from first round of panning (1x1011 CFU) and second (1x1010 CFU) round of panning were used, as input phages for second and third round of panning, respectively. Phages after third round of panning were infected in TGI cells as mentioned before and phagemid DNA was isolated for scFv cloning in suitable expression vector.
Example 5: Screening of individual scFv clones as soluble antibody fragment proteins
The scFv genes from the enriched library produced after 3 rounds of panning was cloned into the expression vector pOPE101 (Progen, Germany) such that the individual scFv clones could be produced as HIS-tagged fusion products. Both the vector DNA (pOPE101) and phagemid DNA were digested with restriction enzymes (Ncol and Notl) to isolate vector and scFv gene, respectively. Both restriction digested vector and scFv gene were ligated and transformed to TG1 electrocompetent cells. Transformed cells were plated on to the 2xYT agar plates containing carbenicillin antibiotic. Individual clones were picked from the 2xYT agar plates and cultured in 15 mL tube with 5 mL of 2xYT media containing carbenicillin or ampicillin (100 μL / mL) overnight at 32 °C at 200 rpm. Next day, cultures were reinoculated to fresh 2xYT medium containing carbenicillin (100 μg / mL) and glucose (0.1 %) at a volumetric ratio of 1:200. Cultures were grown until the OD600 reached ~0.6-0.8. After that ImM Isopropyl β-D-1-thiogalactopyranoside (IPTG) was added to the culture and grown overnight at 30 °C at 200 rpm. Overnight culture was spun at 10,800g for 15 minutes and supernatant was removed. Cell pellet was resuspended in 1/20th volume of the original culture in buffer (30mM Tris-Cl, pH 7.0, 20 % Sucrose and ImM EDTA) and incubated on ice for 30 minutes. Resuspended pellet was centrifuged at 10,800g for 15 minutes and supernatant was collected as the periplasmic fraction containing the soluble His -tagged scFv. This periplasmic fraction was used in immunoassays to study properdin-binding.
We claim,
1. An anti-properdin antibody or antigen binding portion thereof comprising:
(a) CDRH1 of the general formula (I): G-Y-X1a-X2a-X3a-X4a-X5a-X6a-X7a;
(b) CDRH2 of the general formula (II) : X1b-I-X2b-X3b-X4b-X5b-X6b-X7b;
(c) CDRH3 of the general formula (III): X1c-X2c-X3c-X4c-X5c-X6c-X7c-X8c-X9c-X10c- X11c-X12c-X13c-X14c;
(d) CDRL1 of the general formula (IV): X1d-X2d-X3d-X4d-X5d-X6d-X7d-X8d-X9d-X10d- X11d-X12d-X13d-X14d-X15d-X16d-X17d;
(e) CDRL2 of the general formula (V): X1e-X2e-X3e-X4e-X5e-X6e-X7e and
(f) CDRL3 of the general formula (VI): X1f-X2f-X3f-X4f-X5f- X6f-X7f-X8f-X9f-X10f-X11f wherein,
X1a is an amino acid selected from serine and threonine;
X2a is an amino acid selected from phenylalanine and isoleucine;
X3a is an amino acid selected from threonine and alanine;
X4a is an amino acid selected from aspartic acid, serine and histidine;
X5a is an amino acid selected from tyrosine, asparagine, glycine and threonine;
Each of X6a and X7a may be present or absent and when present, is tyrosine amino acid;
X1b is an amino acid selected from valine, leucine, tyrosine and glutamic acid;
X2b is an amino acid selected from serine, asparagine and aspartic acid;
X3b is an amino acid selected from threonine, proline and tyrosine;
X4b is an amino acid selected from tyrosine, glycine, aspartic acid and serine;
X5b is an amino acid selected from tyrosine, threonine, glycine and alanine;
X6b is an amino acid selected from glycine, aspartic acid and threonine;
X7b is an amino acid selected from aspartic acid, tyrosine and asparagine;
X1c is an amino acid selected from aspartic acid, glutamic acid, alanine, and arginine;
X2c is an amino acid selected from leucine, aspartic acid, lysine and glycine;
X3c is an amino acid selected from aspartic acid, tyrosine, serine and leucine;
X4c is an amino acid selected from glycine, aspartic acid, arginine, tyrosine, leucine, serine and lysine;
X5c is an amino acid selected from tyrosine, arginine, aspartic acid, and glycine;
X6c is an amino acid selected from glutamic acid, serine, phenylalanine, tyrosine and asparagine;
X7c is an amino acid selected from serine, proline, aspartic acid, and phenylalanine or no amino acid;
X8c is an amino acid selected from methionine, tryptophan, phenylalanine and valine or no amino acid;
X9c is an amino acid selected from aspartic acid, and phenylalanine or no amino acid;
Each of X10c and X11c is present or absent and when present, is an amino acid independently selected from tyrosine and alanine;
Each of X12c, X13c and X14c is present or absent and when present, is an amino acid independently selected from methionine, aspartic acid and tyrosine;
X1d is an amino acid selected from arginine, lysine, leucine, serine, tyrosine and glutamic acid;
X2d is an amino acid selected from proline, serine, alanine, leucine, glycine and glutamime;
X3d is an amino acid selected from serine, aspartic acid, arginine and tryptophan;
X4d is an amino acid selected from glutamine, glycine, serine and leucine;
X5d is an amino acid selected from aspartic acid, serine, threonine, proline and leucine; X6d is an amino acid selected from isoleucine, valine, leucine, serine, asparagine, phenylalanine and glycine;
X7d is an amino acid selected from asparagine, leucine, glycine, proline, isoleucine, lysine and histidine;
X8d is an amino acid selected from asparagine, aspartic acid, threonine, glycine, arginine, glutamine and tyrosine;
X9d is an amino acid selected from tyrosine, isoleucine, tryptophan, asparagine, glycine, valine, histidine and serine;
X10d is an amino acid selected from leucine, asparagine, threonine, lysine, arginine and serine;
X11dis an amino acid selected from serine, glycine, alanine, tyrosine, proline, aspartic acid and asparagine;
X12d is an amino acid selected from lysine, valine, threonine, alanine and glutamine or no amino acid;
X13d is an amino acid selected from threonine, serine, asparagine and lysine or no amino acid;
Each of X14d, X15d, X16d and X17d is present or absent and when present, is an amino acid independently selected from tyrosine, leucine, asparagine and alanine;
X1e is an amino acid selected from aspartic acid, tryptophan, tyrosine, leucine and alanine;
X2e is an amino acid selected from asparagine, alanine, threonine and valine;
X3e is an amino acid selected from asparagine, serine and threonine;
X4e is an amino acid selected from lysine, threonine, arginine and serine;
X5e is an amino acid selected from arginine and leucine;
X6e is an amino acid selected from phenylalanine, glutamic acid, histidine, aspartic acid and alanine;
X7e is an amino acid selected from serine and aspartic acid;
In one of the embodiments, CDR3 of the light chain (herein after referred as CDRL3) of the anti-properdin antibody or antigen binding portion thereof of the present invention has an amino acid sequence of X1f-X2f-X3f-X4f-X5f-X6f-X7f-X8f-X9f-X10f-X11f X1f is an amino acid selected from histidine, glutamine, tryptophan, alanine, glycine and methionine;
X2f is an amino acid selected from glutamine, alanine and threonine;
X3f is an amino acid selected from tyrosine, glycine, leucine, arginine, tryptophan and glutamine;
X4f is an amino acid selected from leucine, asparagine, threonine, tyrosine, glutamine and aspartic acid;
X5f is an amino acid selected from serine, threonine, histidine, alanine and glycine; X6f is an amino acid selected from serine, leucine, phenylalanine, threonine, isoleucine and tyrosine;
X7f is an amino acid selected from tyrosine, proline and leucine;
X8f is an amino acid selected from threonine, proline, tyrosine, tryptophan and arginine;
X9f is an amino acid selected from threonine and glutamic acid or no amino acid;
X10f is an amino acid selected from alanine and leucine or no amino acid and X11f is valine amino acid or no amino acid.
2. The antibody or antigen binding portion thereof as claimed in claim 1 comprising: (a) CDRH1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 2, 3, 4 and 5, and conservative modifications thereof;
(b) CDRH2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 6, 7, 8, 9, 10 and 11, and conservative modifications thereof;
(c) CDRH3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 12, 13, 14, 15, 16, 17 and 18, and conservative modifications thereof;
(d) CDRL1 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 and 29, and conservative modifications thereof;
(e) CDRL2 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 30, 31, 32, 33 and 34, and conservative modifications thereof; and
(f) CDRL3 comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 35, 36, 37, 38, 39, 40, 41, 42 and 43, and conservative modifications thereof.
3. The antibody or antigen binding portion thereof as claimed in claim 2 is selected from the group comprising of:
(a) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1, a heavy chain variable region CDRH2 comprising SEQ ID NO: 7, a heavy chain variable region CDRH3 comprising SEQ ID NO: 13, a light chain variable region CDRL1 comprising SEQ ID NO: 20, a light chain variable region CDRL2 comprising SEQ ID NO: 31; and a light chain variable region CDRL3 comprising SEQ ID NO: 37;
(b) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1, a heavy chain variable region CDRH2 comprising SEQ ID NO: 7, a heavy chain variable region CDRH3 comprising SEQ ID NO: 13, a light chain variable region CDRL1 comprising SEQ ID NO: 21, a light chain variable region CDRL2 comprising SEQ ID NO: 32; and a light chain variable region CDRL3 comprising SEQ ID NO: 38;
(c) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1, a heavy chain variable region CDRH2 comprising SEQ ID NO: 7, a heavy chain variable region CDRH3 comprising SEQ ID NO: 13, a light chain variable region CDRL1 comprising SEQ ID NO: 21, a light chain variable region CDRL2 comprising SEQ ID NO: 32 and a light chain variable region CDRL3 comprising SEQ ID NO: 36;
(d) a heavy chain variable region CDRH1 comprising SEQ ID NO: 2, a heavy chain variable region CDRH2 comprising SEQ ID NO: 8, a heavy chain variable region
CDRH3 comprising SEQ ID NO: 14, a light chain variable region CDRL1 comprising SEQ ID NO: 20, a light chain variable region CDRL2 comprising SEQ ID NO: 31 and a light chain variable region CDRL3 comprising SEQ ID NO: 36;
(e) a heavy chain variable region CDRH1 comprising SEQ ID NO: 3, a heavy chain variable region CDRH2 comprising SEQ ID NO: 9, a heavy chain variable region CDRH3 comprising SEQ ID NO: 15, a light chain variable region CDRL1 comprising SEQ ID NO: 22, a light chain variable region CDRL2 comprising SEQ ID NO: 33 and a light chain variable region CDRL3 comprising SEQ ID NO: 39;
(f) a heavy chain variable region CDRH1 comprising SEQ ID NO: 4, a heavy chain variable region CDRH2 comprising SEQ ID NO: 10 a heavy chain variable region CDRH3 comprising SEQ ID NO: 16, a light chain variable region CDRL1 comprising SEQ ID NO: 23, a light chain variable region CDRL2 comprising SEQ ID NO: 34 and a light chain variable region CDRL3 comprising SEQ ID NO: 40;
(g) a heavy chain variable region CDRH1 comprising SEQ ID NO: 5, a heavy chain variable region CDRH2 comprising SEQ ID NO: 11, a heavy chain variable region CDRH3 comprising SEQ ID NO: 18, a light chain variable region CDRL1 comprising SEQ ID NO: 29, a light chain variable region CDRL2 comprising SEQ ID NO: 30 and a light chain variable region CDRL3 comprising SEQ ID NO: 41;
(h) a heavy chain variable region CDRH1 comprising SEQ ID NO: 5, a heavy chain variable region CDRH2 comprising SEQ ID NO: 11, a heavy chain variable region CDRH3 comprising SEQ ID NO: 17, a light chain variable region CDRL1 comprising SEQ ID NO: 29, a light chain variable region CDRL2 comprising SEQ ID NO: 30 and a light chain variable region CDRL3 comprising SEQ ID NO: 41; and
(i) a heavy chain variable region CDRH1 comprising SEQ ID NO: 1, a heavy chain variable region CDRH2 comprising SEQ ID NO: 6, a heavy chain variable region CDRH3 comprising SEQ ID NO: 12, a light chain variable region CDRL1 comprising SEQ ID NO: 19, a light chain variable region CDRL2 comprising SEQ ID NO: 30 and a light chain variable region CDRL3 comprising SEQ ID NO: 35.
4. The antibody or antigen binding portion thereof as claimed in claim 1 comprising:
(a) the heavy chain variable region comprises an amino acid sequence that is at least 80 % homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs: 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 and 55;
(b) the light chain variable region comprises an amino acid sequence that is at least 80 % homologous to an amino acid sequence selected from the group consisting of SEQ ID NOs: 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82 and 83.
5. The antibody or antigen binding portion thereof as claimed in claim 4 is selected from the group comprising of:
(a) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
51, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 63;
(b) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
52, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 64;
(c) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
53, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 65;
(d) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
54, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 66;
(e) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
45, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57;
(f) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
45, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 58;
(g) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
45, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 59;
(h) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
46, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57;
(i) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
47, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 60;
(j) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
48, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 61;
(k) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
55, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 79;
(l) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
55, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 56;
(m)a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
50, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 62;
(n) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
44, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 56;
(o) a heavy chain variable region comprising the amino acid sequence of SEQ ID NO:
49, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 62;
6. The antibody or antigen binding portion thereof as claimed in any preceding claims that binds to human properdin.
7. The antibody as claimed in any preceding claims that binds to human properdin with a KD of 10-8 M or less, preferably 10-10 M or less.
8. The antibody as claimed in any preceding claims which is an IgG isotype, preferably an IgG1 or IgG4.
9. The antibody as claimed in any preceding claims has modified or reduced or no ADCC and / or CDC activity.
10. The antibody as claimed in any preceding claims has ADCC and / or CDC activity.
11. The antibody as claimed in any preceding claims comprising single amino acid substitution selected from S228P, P329G, M428L, N434S and suitable combination thereof.
12. The antibody or antigen binding portion thereof as claimed in any preceding claims, wherein the antibody or antigen binding portion thereof comprising at least one of the following characteristics:
(a) cross-reacts with properdin from species other than human;
(b) higher binding specificity towards human properdin;
(c) prevents the increased binding of C3b to the target cell surface;
(d) blocks the function of properdin in mediating alternate complement pathway activation;
(e) prevents the complement mediated lysis of the target cells;
(f) regulates the MAC formation on the target cell surface and thereby preventing the lysis of cells;
(g) minimises the formation of anaphylatoxins, C3a and C5a; and
(h) increased half-life in subject.
13. The antibody or antigen binding portion thereof as claimed in any preceding claims which is murine, chimeric, recombinant or humanized in nature, preferably humanized in nature.
14. A composition comprising the antibody, or antigen-binding portion thereof, of any one of claims 1-13, and a pharmaceutically acceptable carrier.
15. An immunoconjugate comprising the antibody, or antigen -binding portion thereof, of any one of claims 1-13, linked to a therapeutic agent.
16. The immunoconjugate of claim 15, wherein the therapeutic agent is a cytotoxin or a radioactive isotope.
17. A bispecific molecule comprising the antibody, or antigen-binding portion thereof, of any one of claims 1-13, linked to a second functional moiety having a different binding specificity than said antibody, or antigen-binding portion thereof.
18. The bispecific molecule as claimed in claim 17 wherein, the second functional moiety binds to antigen selected from C3, C5, C5a, C5b, C3a, C3b, Factor B, Factor H and C1q.
19. A nucleic acid sequence encoding the antibody, or antigen -binding portion thereof, of any one of claims 1-13.
20. An expression vector comprising the nucleic acid sequence of claim 19.
21. A host cell comprising the expression vector of claim 20.
22. A combination comprising at least two or more antibodies or antigen binding portion thereof wherein at least one antibody or antigen binding portion thereof of any one of claims 1-13.
23. The combination as claimed in claim 22 comprising second antibody or antigen binding portion thereof selected from anti-C3 antibody, anti-C5 antibody, anti-C5a antibody, anti-C5b antibody, anti-C3a antibody, anti-C3b antibody, anti-Factor B antibody, eculizumab, lampalizumab, ravulizumab, anti-properdin antibody.
24. The antibody or antigen binding portion thereof as claimed in any preceding claims wherein the said antibody is administered in combination with chemically synthesised therapeutic drug(s) or vaccine(s) or chemotherapeutic agent for the treatment of various cancers, infections or autoimmune disorders.
25. The antibody or antigen binding portion thereof as claimed in any preceding claims is used for the treatment of diseases where diseases mediated, directly or indirectly, by a component of the alternative complement pathway, and/or by a factor generated following activation of the alternative complement pathway.