METHOD FOR PREPARING POLYETHYLENE GLYCOL-MODIFIED URATE OXIDASE
20230346896 · 2023-11-02
Assignee
Inventors
- Riyong LIU (Hangzhou, CN)
- Zhiming WANG (Hangzhou, CN)
- Yunfeng HE (Hangzhou, CN)
- Yu WANG (Hangzhou, CN)
- Zhicheng FU (Hangzhou, CN)
- Tianwen YAN (Hangzhou, CN)
- Chunlan HU (Hangzhou, CN)
- Guowei SU (Hangzhou, CN)
- Changcheng TAN (Hangzhou, CN)
- Xupeng DING (Hangzhou, CN)
- Hui YANG (Hangzhou, CN)
- Hongying WANG (Hangzhou, CN)
- Qiong DING (Hangzhou, CN)
- Qian Wang (Hangzhou, CN)
- Haiyan WEN (Hangzhou, CN)
- Kai FAN (Hangzhou, CN)
Cpc classification
A61K47/10
HUMAN NECESSITIES
A61K47/60
HUMAN NECESSITIES
C12N9/96
CHEMISTRY; METALLURGY
International classification
A61K47/10
HUMAN NECESSITIES
Abstract
Provided is a method for preparing a polyethylene glycol-modified urate oxidase, at least 11 of the following amino acid sites of the polyethylene glycol-modified urate oxidase have a PEG modification: T.sup.1, K.sup.3, K.sup.4, K.sup.30, K.sup.35, K.sup.76, K.sup.79, K.sup.97, K.sup.112, K.sup.116, K.sup.120, K.sup.152, K.sup.179, K.sup.222, K.sup.231, K.sup.266, K.sup.272, K.sup.285, K.sup.291, and K.sup.293, and the preparation method includes: performing a coupling reaction between urate oxidase and polyethylene glycol, wherein the polyethylene glycol is provided in the form of an acidic solution, and a molar ratio of the urate oxidase to the polyethylene glycol is 1: (56 to 94), to obtain the polyethylene glycol-modified urate oxidase.
Claims
1. A method for preparing a polyethylene glycol-modified urate oxidase, characterized by performing a coupling reaction between urate oxidase and polyethylene glycol to obtain the polyethylene glycol-modified urate oxidase, wherein the polyethylene glycol is provided in a form of an acidic solution, and a molar ratio of the urate oxidase to the polyethylene glycol is 1: (56 to 94).
2. The method according to claim 1, wherein the acidic solution contains at least one selected from organic acids and/or inorganic acids.
3. The method according to claim 2, wherein the organic acids are selected from acetic acid, oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid, malonic acid, adipic acid, ascorbic acid, benzenesulfonic acid, benzoic acid, butyric acid, cyclopentylpropionic acid, digluconic acid, dodecylsulfuric acid, ethanesulfonic acid, formic acid, fumaric acid, glucoheptonic acid, glycerophosphoric acid, gluconic acid, heptanoic acid, hexanoic acid, 2-hydroxyethanesulfonic acid, digalacturonic acid, lactic acid, lauric acid, laurylsulfuric acid, malic acid, malonic acid, methanesulfonic acid, 2-naphthalenesulfonic acid, nicotinic acid, oleic acid, palmitic acid, pectic acid, 3-phenylpropionate, picrate, pivalic acid, propionic acid, stearic acid, p-toluenesulfonic acid, undecanoic acid, or pentanoic acid; and the inorganic acids are selected from hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid, perchloric acid, hydriodic acid, nitric acid, persulfuric acid, boric acid, dichromic acid, silicic acid, chromic acid, or thiocyanic acid.
4. The method according to claim 2, wherein a concentration of hydrogen ions in the acidic solution ranges from 1 mmol/L to 5 mmol/L.
5. The method according to claim 2, wherein the acidic solution contains hydrochloric acid, sulfuric acid, or glacial acetic acid.
6. The method according to claim 5, wherein a concentration of the acid in the acidic solution ranges from 1 mmol/L to 5 mmol/L.
7. The method according to claim 1, wherein a concentration of the polyethylene glycol in the acidic solution ranges from 100 mmol/L to 300 mmol/L.
8. The method according to claim 1, wherein the polyethylene glycol has a molecular weight of not more than 6 KD; or the polyethylene glycol has a monomethoxy group or a hydroxyl group; or the polyethylene glycol is of a linear or branched structure; or the polyethylene glycol is coupled to the urate oxidase via an amide bond.
9. The method according to claim 1, wherein the polyethylene glycol is a modifying polyethylene glycol, and a modification group of the modifying polyethylene glycol is at least one selected from the group consisting of N-hydroxysuccinimide, N-hydroxysuccinimidyl carbonate, N-hydroxysuccinimidyl acetate, N-hydroxysuccinimidyl propionate, N-hydroxysuccinimidyl butyrate, N-hydroxysuccinimidyl succinate, and bis(p-nitrophenyl) carbonate.
10. The method according to claim 9, wherein the modification group of the modifying polyethylene glycol is N-hydroxysuccinimide propionate.
11. The method according to claim 1, wherein the coupling reaction is performed in a carbonate buffer solution, wherein the carbonate buffer solution has a pH of 9 to 11.
12. The method according to claim 1, wherein a concentration of the urate oxidase in a coupling reaction system is 10 mg/ml.
13. The method according to claim 1, wherein the coupling reaction is performed at 5° C. to 30° C. for at least 60 min.
14. The method according to claim 1, wherein at least 11 of the following amino acid sites in the urate oxidase have a PEG modification: T.sup.1, K.sup.3, K.sup.4, K.sup.30, K.sup.35, K.sup.76, K.sup.79, K.sup.97, K.sup.112, K.sup.116, K.sup.120, K.sup.152, K.sup.179, K.sup.222, K.sup.231, K.sup.266, K.sup.272, K.sup.285, K.sup.291, and K.sup.293. wherein the amino acid sites are positioned based on an amino acid sequence set forth as SEQ ID NO: 1.
15. The method according to claim 1, wherein the urate oxidase has an amino acid sequence set forth as any one of SEQ ID NOs: 1 to 7; or the urate oxidase is a polypeptide having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or at least 99% identity with any one of SEQ ID NOs: 1 to 7; or the urate oxidase is a polypeptide having an amino acid sequence set forth as any one of SEQ ID NOs: 1 to 7 in which one or more amino acids are substituted, deleted and/or added.
16. The method according to claim 14, wherein the urate oxidase has an amino acid sequence set forth as any one of SEQ ID NOs: 1 to 4.
17. The method according to claim 1, wherein at least one of the following four amino acid sites of the polyethylene glycol-modified urate oxidase has a PEG modification: K.sup.30, K.sup.35, K.sup.222, and K.sup.231, wherein the amino acid sites are positioned based on an amino acid sequence set forth as SEQ ID NO: 1.
18. The method according to claim 1, wherein peak areas of at least 11 predetermined peptide fragments in a peptide map of the polyethylene glycol-modified urate oxidase are reduced by a relative proportion of 75% or more, preferably 80% or more, more preferably 90% or more, compared with urate oxidase unmodified with polyethylene glycol.
19. The method according to claim 18, wherein the peptide map of the polyethylene glycol-modified urate oxidase has peptide fragments with peak area reduction shown in Table 8.
20. The method according to claim 18, wherein the peptide map of the polyethylene glycol-modified urate oxidase is shown in
Description
BRIEF DESCRIPTION OF DRAWINGS
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DESCRIPTION OF EMBODIMENTS
[0077] The embodiments of the present disclosure are described in detail below, and examples of the embodiments are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are illustrative and are intended to explain the present disclosure, but should not be understood as a limitation of the present disclosure.
[0078] An object of the present disclosure is to provide a method for preparing a polyethylene glycol-modified urate oxidase.
[0079] Another object of the present disclosure is to provide a novel polyethylene glycol-modified urate oxidase.
[0080] Another object of the present disclosure is to provide a method for effectively reducing the immunogenicity of urate oxidase, which can effectively reduce the immunogenicity of urate oxidase and improve the safety and stability of urate oxidase in vivo.
[0081] Another object of the present disclosure is to provide the use of the polyethylene glycol-urate oxidase conjugate obtained as above, which can achieve a long-lasting efficacy in vivo and significantly reduce the serum uric acid level, and can be used for the treatment of hyperuricemia and gout.
[0082] As used herein, the terms “urate oxidase” and “uricase” are interchangeable, and they both refer to a class of enzymes described in the present disclosure that can catalyze the oxidation of uric acid to produce allantoin and hydrogen peroxide. The terms “urate oxidase analogue”, “uricase analogue”, and “uricase derivative” are interchangeable, and they all refer to that parts of amino acids of a protein structural sequence of urate oxidase can be subjected to a structural modification such as substitution, deletion, or addition under the premise that the activity of urate oxidase for specifically catalyzing the conversion of uric acid into allantoin and hydrogen peroxide is maintained, thereby achieving the advantages of the present disclosure, including but not limited to reducing immunogenicity, increasing protein stability, and facilitating further polyethylene glycol modification.
[0083] Urate oxidase is not particularly limited, and can be urate oxidase and urate oxidase analogues derived from any source. Representative examples include, but are not limited to, mammalian sources, microorganisms, plants, etc.
[0084] In another preferred embodiment, the urate oxidase and urate oxidase analogues thereof are derived from mammals, preferably, the amino acid sequence set forth as any one of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4, and more preferably, the amino acid sequence set forth as SEQ ID NO: 1.
[0085] The urate oxidase derived from different species according to the present disclosure can be obtained through various manners, including but not limited to natural extraction, chemical synthesis, genetic engineering recombinant expression, etc.
[0086] In another preferred embodiment, through recombinant technology of urate oxidase, a coding sequence of the urate oxidase protein sequence (SEQ ID NO: 1) is subjected to recombinant expression in a host cell.
[0087] In another preferred embodiment, the urate oxidase is prepared and obtained in a manner that E. coli or yeast is used as a host to construct a recombinant expression strain, and E. coli is more preferably used as host bacteria for recombinant expression.
[0088] As used herein, the polyethylene glycol-modified urate oxidase described in the present disclosure is obtained by covalently modifying urate oxidase with polyethylene glycol. The polyethylene glycol (PEG) refers to a mixture of ethylene oxide condensation polymer and water, represented by a general formula H(OCH.sub.2CH.sub.2).sub.nOH, which is a hydrophilic and linear or branched polymer with neutral pH and high water solubility and without toxicity. Due to the non-toxicity and good biocompatibility of PEG, the FDA has approved a variety of PEG-modified recombinant protein drugs on the market, proving that PEG can be used to reduce the immunogenicity of the protein, increase the solubility of the protein, and extend the half-life of the protein. In order to bind PEG to protein, one or more ends of PEG need to be activated, and the activation can be performed by selecting the corresponding modification groups according to the groups on the target protein to be modified, such as amino, sulfhydryl, carboxyl or hydroxyl.
[0089] In another preferred embodiment, a site of urate oxidase and uricase analogues for PEG modification according to the present disclosure is an ε-amino group of lysine residues, or an α-amino group of a small amount of N-terminal lysine residues. The urate oxidase is covalently connected to the modification group of PEG through a urethane bond, a secondary amino bond, or an amide bond. Preferably, a polyethylene glycol molecule is coupled with urate oxidase to form an amide bond. The modification groups of polyethylene glycol include, but are not limited to, N-hydroxysuccinimides, including but not limited to N-hydroxysuccinimide (NHS), N-hydroxysuccinimidyl carbonate (SC), N-hydroxysuccinimidyl acetate (SCM), N-hydroxysuccinimidyl propionate (SPA), N-hydroxysuccinimidyl butyrate (SBA), N-hydroxysuccinimidyl succinate (SS), etc. The blocking group of polyethylene glycol includes, but is not limited to, monomethoxy, ethoxy, glucose, or galactose, preferably monomethoxy.
[0090] In another preferred embodiment, the polyethylene glycol may be linear or linear.
[0091] In another preferred embodiment, a relative molecular weight of the used polyethylene glycol for polyethylene glycol-modified urate oxidase is not more than 6 KD, preferably 1 KD to 5 KD, and most preferably 5 KD. It should be noted that the “relative molecular weight of polyethylene glycol” mentioned herein refers to a relative molecular weight of polyethylene glycol without modification groups, which has a general meaning in the related art. PEG, after the activation by the active groups, has a total relative molecular weight slightly greater than 5KD, for example, in a range of 5 KD+10%.
[0092] In another preferred embodiment, the polyethylene glycol-modified urate oxidase has the following characteristics:
[0093] (1) At least 11 of the following amino acid sites in the urate oxidase have a PEG modification: T.sup.1, K.sup.3, K.sup.4, K.sup.30, K.sup.35, K.sup.76, K.sup.79, K.sup.97, K.sup.112, K.sup.116, K.sup.120, K.sup.152, K.sup.179, K.sup.222, K.sup.231, K.sup.266, K.sup.272, K.sup.285, K.sup.291, and K.sup.293.
[0094] (2) One urate oxidase molecule is coupled with 11 to 13 polyethylene glycol molecules on average.
[0095] (3) K.sup.30 and/or K.sup.35, as well as K.sup.222 and/or K.sup.231 contained in the urate oxidase sequence set forth as SEQ ID NO: 1 are modified and coupled with polyethylene glycol; and
[0096] (4) The polyethylene glycol-modified urate oxidase has lower immunogenicity in vivo.
[0097] In another aspect of the present disclosure, a method for effectively reducing immunogenicity of urate oxidase is provided. This technology can effectively reduce the immunogenicity of urate oxidase and improve the in vivo stability of urate oxidase.
[0098] As used herein, the polyethylene glycol-modified urate oxidase is characterized in that, the urate oxidase is not particularly limited, and can be urate oxidase and urate oxidase analogues derived from any source, representative examples of which include, but are not limited to, sources of mammals, microorganisms, plants, etc.
[0099] In another preferred embodiment, the urate oxidase and the urate oxidase analogues are derived from mammals. The amino acid sequences of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4 are preferred, and the amino acid sequence of SEQ ID NO: 1 is more preferred.
[0100] The urate oxidase derived from different species according to the present disclosure can be obtained through various manners, including but not limited to natural extraction, chemical synthesis, genetic engineering recombinant expression, etc.
[0101] In another preferred embodiment, the urate oxidase is prepared and obtained in such a manner that E. coli or yeast is used as a host to construct a recombinant expression strain, and E. coli is more preferably used as host bacteria for recombinant expression.
[0102] The urate oxidase of the present disclosure is subjected to recombinant expression in E. coli to obtain a large amount of urate oxidase, and the expressed urate oxidase can be expressed in the cells, on the cell membranes, or secreted out of the cells. If necessary, methods known to those skilled in the art can be used to obtain high-purity urate oxidase. Examples of these methods include, but are not limited to, centrifugation, bacteria destruction, salting out, ultrafiltration, ion exchange chromatography, hydrophobic chromatography, molecular sieve chromatography, and a combination of various other techniques.
[0103] The urate oxidase obtained above can be covalently bound to polyethylene glycol through a linking group using methods known in the art.
[0104] In another preferred embodiment, polyethylene glycol directionally modifies the lysine residues on a surface of a spatial structure of urate oxidase. Urate oxidase is covalently connected to the modification group (also referred to as active group) of PEG through an amide bond. The modification groups (also referred to as active group) of polyethylene glycol include, but are not limited to, N-hydroxysuccinimide (NHS), N-hydroxysuccinimidyl carbonate (SC), N-hydroxysuccinimidyl acetate (SCM), N-hydroxysuccinimidyl propionate (SPA), N-hydroxysuccinimidyl butyrate (SBA), N-hydroxysuccinimidyl succinate (SS), etc. The blocking group of polyethylene glycol includes, but is not limited to, monomethoxy, ethoxy, glucose, or galactose, preferably monomethoxy.
[0105] In another preferred embodiment, the polyethylene glycol may be linear or branched.
[0106] In another preferred embodiment, the relative molecular weight of the polyethylene glycol is not more than 6 KD, preferably 1 KD to 5 KD, more preferably 2 KD, 5 KD, and most preferably 5 KD.
[0107] In another preferred embodiment, the present disclosure provides a method for preparing the polyethylene glycol-modified urate oxidase. The method has one or more of the following features: [0108] (1) a modification feed molar ratio of urate oxidase to polyethylene glycol (urate oxidase: polyethylene glycol) ranges from 1:45 to 1:150, preferably from 1:45 to 1:110, more preferably from 1:56 to 1:94. [0109] (2) a coupling reaction system is carbonate buffer with a modification pH range of 9 to 11. [0110] (3) a urate oxidase protein concentration in the coupling reaction system is 10 mg/ml.
[0111] The above-mentioned method for preparing the polyethylene glycol-modified urate oxidase can obtain high purity polyethylene glycol-modified urate oxidase by using a variety of purification methods.
[0112] In another preferred embodiment, the purification of the modified sample includes, but is not limited to, molecular sieve chromatography, ion exchange chromatography, hydrophobic chromatography, tangential flow ultrafiltration, or combinations thereof. More preferred are molecular sieve chromatography and tangential flow ultrafiltration.
[0113] In another aspect of the present disclosure, uses of the above-mentioned polyethylene glycol-modified urate oxidase are provided. The conjugate can achieve long-lasting efficacy in vivo and significantly reduce serum uric acid level, applicable for the treatment of hyperuricemia and gout.
[0114] The polyethylene glycol-modified urate oxidase is more suitable as a medicament and its composition for treating chronic hyperuricemia or gout. The main symptoms of hyperuricemia and gout include, but are not limited to, uric acid nephropathy and gouty arthritis.
[0115] The administration route of the polyethylene glycol-modified urate oxidase includes, but is not limited to, intravenous injection, subcutaneous injection, intramuscular injection, intraperitoneal injection, etc., preferably intravenous injection, intramuscular injection, and more preferably intramuscular injection.
[0116] The polyethylene glycol-modified urate oxidase has lower immunogenicity in vivo.
[0117] The low immunogenicity of the polyethylene glycol-modified urate oxidase means that, after intramuscular injection of the polyethylene glycol-modified urate oxidase in human body or animal body, the body does not produce antibodies against polyethylene glycol molecules or produces low titer antibodies against polyethylene glycol molecules, and also does not produce antibodies against urate oxidase.
[0118] The polyethylene glycol-modified urate oxidase has a longer half-life in vivo and the efficacy in reducing the uric acid level in the blood after intramuscular injection.
[0119] According to some embodiments of the present disclosure, the pharmaceutical composition including the polyethylene glycol-modified urate oxidase of the present disclosure may further include a pharmaceutically acceptable carrier, and the dosage form and mode of administration of the pharmaceutical composition are not particularly limited. For injection preparations, pharmaceutically acceptable carriers can include buffers, preservatives, analgesics, solubilizers, isotonic agents, and stabilizers. For locally administered preparations, pharmaceutically acceptable carriers may include bases, excipients, lubricants, and preservatives. The pharmaceutical compositions of the present disclosure can be formulated in various dosage forms in combination with pharmaceutically acceptable carriers as described above.
[0120] Excipients and diluents suitable for use in carriers for pharmaceutical formulations according to some specific examples of the present disclosure may include: lactose, glucose, sucrose, sorbitol, mannitol, xylitol, erythritol, maltitol, starch, acacia, alginates, gel, calcium phosphate, calcium silicate, cellulose, methyl cellulose, microcrystalline cellulose, polyvinylpyrrolidone, water, methyl hydroxybenzoate, propyl hydroxybenzoate, talc, magnesium stearate, and mineral oil.
[0121] In accordance with some other embodiments of the present disclosure, the pharmaceutical composition of the present disclosure may further include fillers, anticoagulants, lubricants, buffers, osmotic pressure regulators, humectants, fragrances, preservatives, and the like.
[0122] According to the embodiments of the present disclosure, under the premise of maintaining the enzyme activity to the maximal extent, the polyethylene glycol-modified urate oxidase and the pharmaceutical composition of the present disclosure can greatly enhance the in vivo stability of urate oxidase and reduce the immunogenicity, and after intramuscular injection, the in vivo efficacy thereof can be equivalent to an in vivo efficacy after intravenous injection of an original patented drug. Therefore, the polyethylene glycol-modified urate oxidase of the present disclosure and the pharmaceutical composition containing the polyethylene glycol-modified urate oxidase can be administered when treating or preventing the hyperuric acid-related diseases.
[0123] The term “administration” as used herein refers to the introduction of a predetermined amount of a substance into a patient in a suitable manner. The polyethylene glycol-modified urate oxidase of the present disclosure can be administered through any common route, as long as it can reach the desired tissue. Various administration routes are conceivable, including peritoneal, intravenous, intramuscular, subcutaneous, cortical, oral, topical, nasal, pulmonary, and rectal administrations. The present disclosure is not limited to these illustrative administration routes. However, during oral administration, the active ingredients of the orally administered composition should be coated or formulated to prevent their degradation in the stomach. Preferably, the composition of the present disclosure can be administered in the form of injections. In addition, the pharmaceutical composition of the present disclosure can be administered using a specific device configured to deliver the active ingredient to the target cells.
[0124] The administration frequency and dose of the pharmaceutical composition of the present disclosure can be determined based on a number of related factors, including the type of disease to be treated, the administration route, the patient's age, gender, and weight, and the severity of the disease, as well as the type of the medicament serving as the active ingredient.
[0125] The term “therapeutically effective amount” refers to an amount of a compound that is sufficient to significantly ameliorate certain symptoms associated with a disease or condition, that is, an amount that provides a therapeutic effect for a given condition and dose regimen. For example, in the treatment of chronic hyperuricemia or gout, drugs or compounds that reduce, prevent, delay, inhibit, or block any symptoms of a disease or disorder should be therapeutically effective. A therapeutically effective amount of the drug or compound is not necessarily to cure the disease or condition, but will provide treatment for the disease or condition such that the onset of the disease or condition of an individual is delayed, blocked, or prevented, or the symptoms of the disease or condition are alleviated, or the duration of the disease or condition is changed, or, for example, the disease or illness becomes less serious, or recovery is accelerated.
[0126] The term “treatment” is used to refer to obtaining a desired pharmacological and/or physiological effect. Said effect may be prophylactic in terms of complete or partial prevention of the disease or its symptoms, and/or may be therapeutic in terms of partial or complete cure of the disease and/or adverse effects caused by the disease. The “treatment” as used herein covers the treatment of diseases of mammals, especially human (mainly referring to the hyperuric acid-related diseases), including: (a) prevention of diseases in individuals who are prone to a disease but have not yet been diagnosed; (b) inhibition of a disease, such as blocking the development of the disease; or (c) alleviation of a disease, such as reducing the symptoms associated with the disease. The “treatment” as used herein encompasses any medication that administers a medicament or compound to an individual to treat, cure, alleviate, ameliorate, reduce or inhibit the individual's disease, including but not limited to administering the polyethylene glycol-modified urate oxidase described herein to the individual in need thereof
[0127] According to the embodiments of the present disclosure, the polyethylene glycol-modified urate oxidase or pharmaceutical composition of the present disclosure can be used in combination with conventional treatment methods and/or therapies, or can be used separately with conventional treatment methods and/or therapies. When the polyethylene glycol-modified urate oxidase or pharmaceutical composition of the present disclosure is administered in combination therapy with other drugs, they can be administered to the individual sequentially or simultaneously. Alternatively, the pharmaceutical composition of the present disclosure may include a combination of the polyethylene glycol-modified urate oxidase of the present disclosure, a pharmaceutically acceptable carrier or pharmaceutically acceptable excipient, and other therapeutic or preventive drugs known in the art.
[0128] The term “average modification degree” refers to the number of PEGs bound to each uricase monomer.
[0129] In the present disclosure, unless otherwise specified, the expression “amino acid site has PEG modification” means that, in a three-dimensional structure of a corresponding polypeptide, the PEG molecule covers the amino acid site in such a manner that at least a part of groups at the amino acid site is not exposed. Those skilled in the art can understand that, they can determine whether a specific amino acid site is modified by a PEG molecule through conventional technical means, for example, referring to the method listed in the “Detection of Polyethylene Glycol-Modified Sites” in Example 3 of the present disclosure. In short, the method includes: 1) digesting the non-pegylated and pegylated urate oxidases with one or more enzymes, for example, single-enzyme digestion by using Lys-C or Trypsin, or double-enzyme digestion by using Lys-C and Trypsin; 2) separating the digested fragments by high performance liquid chromatography to generate chromatograms of non-pegylated and pegylated urate oxidases, that is, peptide maps; and 3) comparing the peptide maps of the non-pegylated and pegylated urate oxidases to obtain the difference therebetween, and in combination with a predetermined internal standard peptides, determining a relative proportion of reduction or disappearance of peaks of the peptide fragment where specific amino acid sites are located in the pegylated urate oxidase, and further determining whether the specific amino acid sites on the peptide fragment are modified by PEG. Specifically, in Example 3 of the present disclosure, the relative proportion of the reduction or disappearance of the peak area of the peptide fragment where the specific amino acid sites are located can be calculated according to the following equation:
P(%)=(A.sub.2−A.sub.1)/A.sub.2100%, where A.sub.1=A.sub.0×t.
[0130] A.sub.0 is a measured peak area of a peptide fragment where a specific amino acid site of the modified protein to be tested is located, and t is an average ratio of a peak area of the internal reference peptide fragment in a PHC peptide map to that in the peptide map of the modified protein to be tested; P (%) represents a relative proportion of reduction or disappearance of the peak area of the peptide fragment where the specific amino acid site is located, A.sub.2 is a peak area of the peptide fragment where the specific amino acid site is located in the PHC peptide map, and A.sub.1 is an internal reference-converted peak area of the peptide fragment where the specific amino acid site is located in the peptide map of the modified protein to be tested.
[0131] It should be understood that, within the scope of the present disclosure, the above-mentioned technical features of the present disclosure and the various technical features specifically described as below (such as in the embodiments) can be combined with each other to form a new or preferred technical solution, which can be understood more clearly by referring to the following examples. Due to limited length, the described examples are for illustrative purposes only and are not intended to limit the present disclosure.
[0132] Hereinafter, the embodiments of the present disclosure will be described in further detail, and examples of the embodiments are illustrated in the accompanying drawings. The following embodiments described with reference to the accompanying drawings are illustrative, and are intended to explain the present disclosure, but should not be understood as limitations on the present disclosure.
EXAMPLE 1 PREPARATION OF RECOMBINANT URATE OXIDASE
1.1 Construction of Genes and Expression Plasmids for Uricase Expression
[0133] According to the usage preference data of E. coli codon, in combination with factors such as codon preference and GC content, cDNA sequence of the uricase protein (referred to as PHC) (SEQ ID NO:1) was designed, and the whole gene was synthesized and named as pUC-57-PHC plasmid. Nde I and BamH I were used as the target gene insertion sites, and the pET-30a plasmid was used as the expression vector (pET-30a-PHC).
1.2 Transformation of Expression Plasmids into Bacterial Host Cells
[0134] The expression vector pET-30a-PHC was introduced into E. coli BL21 (DE3) by CaC12 method, high expression clones were screened through resistance screening with Kanamycin, and the original seed bank strain (E3B) was preserved. These steps were performed in accordance with the commonly used methods in the field of molecular biology.
1.3 Preparation of Recombinant Urate Oxidase
[0135] The transformed and engineered strains were fermented and expressed in a fermentor, under the control conditions: first culturing at 30° C. and pH 7.2 to an OD.sub.600=30 or higher, then increasing the temperature to about 37° C., adding IPTG to 0.5 mmol/L, and continuing to induce for 3 hours or more to allow urate oxidase to accumulate. The cells were collected by centrifugation, and then preserved below −15° C.
[0136] The frozen bacteria were taken and suspended in a buffer of 25 mmol/L Tris and 5 mmol/L EDTA, at a suspension ratio of 1:10 (W/V). After breaking the bacterial cells with high pressure, the urate oxidase precipitate was collected by centrifugation, the precipitate was washed once with 50 mmol/L NaHCO.sub.3, and the enriched uricase precipitate was suspended in a Na.sub.2HCO.sub.3 buffer (100 mmol/L, pH 9.7 to 10.3) at a suspension ratio of 1:50 (W/V), following by stirring overnight at room temperature to dissolve, and then centrifuging to collect the supernatant.
[0137] Urate oxidase was further purified through several chromatographic steps. The purity detected by SDS-PAGE was 95% or greater, and the purity detected by Superdex 200 column was greater than 95%, with no aggregate form. The protein concentration was determined by Lowry method, and the activity of the urate oxidase was measured by spectrophotometry, where 1 unit (U) of enzyme activity was defined as the amount of enzyme required to convert 1 μmol of uric acid per minute under the reaction temperature of 37° C. and the optimal buffer condition at pH 9.0.
EXAMPLE 2 PREPARATION OF PEGYLATED URATE OXIDASE
[0138] Monomethoxy PEG derivatives with different molecular weights (500 Da to 20,000 Da), such as N-succinimidyl propionate PEG (5K-PEG-SPA) with a molecular weight of 5 K, are dissolved with a 1 to 5 mmol/L acid solution to form a 100 to 300 mmol/L PEG solution, which, after the dissolving, was added to a carbonate buffer solution containing the urate oxidase dissolved therein and having a carbonate concentration of 0.1 to 0.3 mol/L, pH 10.0, according to molar ratio of 1:45 to 1:150 (urate oxidase: 5K-PEG-SPA), thereby allowing a coupling reaction between PEG and urate oxidase. A concentration of the urate oxidase in the coupling reaction was 10 mg/ml. The coupling reaction required stirring at 5 to 30° C. for 60 minutes or more, until the PEG coupling degree no longer changed with time. After the reaction was finished, the PEG not participating in the modification and by-products were removed from the reaction by ultrafiltration and/or chromatography. A suitable molecular sieve chromatography medium was used to separate and remove modified by-products. Finally, the 5 K modified pegylated urate oxidase (referred to as PU5) was obtained through sterile filtration.
EXAMPLE 3: CHARACTERISTIC ANALYSIS OF PEGYLATED URATE OXIDASE
3.1 Detection of Average Modification Degree and Enzyme Activity
[0139] The protein concentration was determined by using Lowry method, and the activity of the polyethylene glycol-modified urate oxidase was determined by using spectrophotometer. The maximum ultraviolet absorption wavelength of uric acid, i.e., the substrate of uricase, was 293 nm, and the maximum ultraviolet absorption wavelength of the product allantoin was 224 nm. Within a certain concentration range, the absorption value of uric acid at 293 nm was in direct proportion to its concentration. The quantitative determination of uric acid can be carried out by spectrophotometer. The specific process was as follows: the UV-Vis spectrophotometer was turned on, the wavelength was adjusted to 293 nm, and the water bath circulation system of the instrument was turned on to keep the temperature at 37° C. Sodium tetraborate buffer was used as a blank control, and zero point was calibrated; 2.95 ml of substrate reaction solution (0.1 mol/L sodium tetraborate, 100 μmol/L uric acid, pH 9.5, preheated to 37° C.) was added in a quartz cuvette, then 50 μl of the test sample was added and mixed quickly to measure the absorption value at 293 nm. The change of the absorbance at 293 nm was continuously measured; a degradation concentration of uric acid was calculated according to C=A/εL (where A is an absorbance of a specific concentration of uric acid at 293 nm, c is a molar extinction coefficient of uric acid, L is an optical path of the cuvette, and C is a molar concentration of uric acid). The enzyme activity was calculated. The enzyme activity was defined as that, at the optimum reaction temperature of 37° C. and the optimum reaction pH 9.5, the amount of enzyme required to convert 1 μmol of uric acid into allantoin per minute is defined as one activity unit (U).
[0140] SEC-HPLC connected in series with UV/RI (a combination of ultraviolet and refractive index detector) was used to detect the average modification degree of polyethylene glycol-modified urate oxidase. Based on the fact that protein has a maximum absorption peak at ultraviolet 280 nm, PEG has no absorption at this wavelength, and the absorption value of the protein and the absorption value of PEG within a certain range by the differential refractive index detector are proportional to the respective concentrations, the content of PEG portion and the content of protein portion in the pegylated urate oxidase can be obtained using an external standard method with PEG reference substance and PHC physical and chemical reference substance, and thus the number of PEG molecules on each urate oxidase monomer, i.e., the average modification degree, can be obtained by the following calculation method.
Average modification degree of PEG-modified urate oxidase=(relative molecular weight of urate oxidase subunit×amount of PEG in sample)/(relative molecular weight of PEG×amount of protein in sample).
[0141] The SEC-HPLC-UV/RI detection spectrums of PHC physical and chemical reference substance, PEG reference substance, and PU5 modified product are illustrated in
[0142] Under different feed ratios in Example 2, the enzyme activity and average modification degree of the obtained polyethylene glycol-modified urate oxidase are shown in Table 1.
TABLE-US-00003 TABLE 1 Enzyme activity and average modification degree at different feed ratios at 5K-PEG Enzyme Average Protein:5K-PEG feed Enzyme activity modification molar ratio activity retention degree Unmodified urate oxidase 11.4 U/mg .sup. 100% 0 1:48 10.71 U/mg 94% 10.3 1:56 11.17 U/mg 103.4% 11.4 1:68 12.2 U/mg 107.1% 11.9 1:82 12.02 U/mg 105.4% 12.3 1:94 11.75 U/mg 103.1% 12.1 1:110 10.83 U/mg 95% 11.5 1:150 10.03 U/mg 88% 10.1
[0143] The enzyme activity and the average modification degree of polyethylene glycol-modified urate oxidase obtained at different molecular weights of PEG and a feed molar ratio of protein to PEG of 1:68 in Example 2 are shown in Table 2.
TABLE-US-00004 TABLE 2 Enzyme activity and average modification degree under modification at different molecular weights of PEG Average modification Enzyme activity Enzyme activity PEG MW(KD) degree (U/mg) retention 0 — 11.3 .sup. 100% 2 11.7 11.6 102.7% 3.5 11.5 11.4 100.9% 5 11.8 12.1 107.1% 10 11.7 11.8 104.4% Notes: the average modification degree represents the number of PEG molecules on each urate oxidase monomer.
[0144] It can be seen from Table 1 and Table 2 that the polyethylene glycol-modified urate oxidase of the present disclosure has an average modification degree of 11 or more, and the enzyme activity was higher than that of unmodified urate oxidase, the enzyme activity retention was high, the enzyme activity is even increased instead of decreasing, and the enzyme activity was relatively stable. This is inconsistent with the viewpoint taught by the original patented drug that the low-molecular-weight PEG modification will lead to a decrease in enzyme activity, and the polyethylene glycol-modified urate oxidase obtained in the present disclosure has a higher average modification degree with polyethylene glycol, thus achieving unexpected technical effects in terms of enzyme activity retention.
[0145] Meanwhile, the inventors measured the immunogenicity of urate oxidase obtained under the modification of PEGs with different molecular weights, and the experimental results are shown in Table 3.
TABLE-US-00005 TABLE 3 In vivo antibody results of urate oxidase modified by PEGs with different molecular weights in mice Anti-PEG antibody Anti-uricase protein antibody Average Antibody Antibody Antibody Antibody PEG modification positive titer positive titer MW(KD) degree rate range rate range 0 (unmodified) — 0/8 — 8/8 1:51200 to 1:204800 2 11.7 1/8 1:100 to 1:400 2/8 1:100 to 1:300 3.5 11.5 1/8 1:100 to 1:600 2/8 1:50 to 1:100 5 11.8 2/8 1:100 to 1:700 1/8 1:20 to 1:50 10 11.7 4/8 1:1600 to 2/8 1:50 to 1:100 1:12800
[0146] In the experiment, mice were divided into groups with 8 mice in each group. Intravenous administration of 1 mg/kg was given to each animal once a week. After four consecutive times of administration, blood samples were collected to evaluate the anti-PEG and anti-urate oxidase immunogenicity. As can be seen from the results in Table 3, in the case of consistent average modification degree, as the molecular weight of PEG increases, the positive rate of anti-PEG antibody generated increases, and when the molecular weight of PEG exceeds 5 KD, the positive rate of anti-PEG antibody and antibody titer significantly increase. It can be seen from the analysis of anti-urate oxidase results that PEG modification can significantly reduce the antibody positive rate and antibody titer of urate oxidase, and in the case of consistent average modification degree, in the range of 2 K to 5 K, the generated anti-urate oxidase antibody positive rate and antibody titer become lower with the increase of PEG molecular weight, while when the PEG molecular weight is greater than 5K, the risk of anti-uricase antibody will also occur. In conclusion, 2 to 5 K PEG modified urate oxidase is superior to 10K PEG modified urate oxidase, and 5 KD is more preferred.
[0147] Finally, the inventors measured the enzyme activity and the average modification degree of urate oxidase obtained by modification with PEGs dissolved with different acids. The acid solution used may be selected from organic acids such as acetic acid, oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid, malonic acid, adipic acid, ascorbic acid, benzenesulfonic acid, benzoic acid, butyric acid, cyclopentylpropionic acid, digluconic acid, dodecylsulfuric acid, ethanesulfonic acid, formic acid, fumaric acid, glucoheptonic acid, glycerophosphoric acid, gluconic acid, heptanoic acid, hexanoic acid, 2-hydroxyethanesulfonic acid, digalacturonic acid, lactic acid, lauric acid, laurylsulfuric acid, malic acid, malonic acid, methanesulfonic acid, 2-naphthalenesulfonic acid, nicotinic acid, oleic acid, palmitic acid, pectic acid, 3-phenylpropionate, picrate, pivalic acid, propionic acid, stearic acid, p-toluenesulfonic acid, undecanoic acid, and valeric acid; and may also be selected from inorganic acids such as hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid, perchloric acid, hydriodic acid, nitric acid, peroxydisulfuric acid, boric acid, dichromic acid, silicic acid, chromic acid, and thiocyanic acid. Different types of acid solutions can achieve the dissolution of PEG and uricase modification. The different PEG feed ways and feed ratios are shown in Table 4 below.
TABLE-US-00006 TABLE 4 Influence of different feed ways and feed ratios on PEG modification results Feed ratios (molar Average feed ratio) modification Enzyme PEG feed ways Protein:5K-PEG degree activity Feeding with Dry 1:48 8.8 8.96 U/mg powder 1:56 9.3 9.18 U/mg 1:94 9.8 9.26 U/mg 1:110 9.2 9.16 U/mg Dissolving with 1:48 10.8 10.96 U/mg hydrochloric acid 1:56 11.4 11.21 U/mg 1:94 12.4 11.35 U/mg 1:110 12.2 10.76 U/mg Dissolving with 1:94 11.9 11.16 U/mg sulfuric acid Dissolving with 1:94 11.7 11.03 U/mg glacial acetic acid
[0148] The inventors found that dissolving PEG with acid before feeding results in a higher protein modification rate and higher enzyme activity, and significant saves the amount of PEG used compared with feeding directly with dry powder.
3.2 Detection of Polyethylene Glycol Modification Sites
[0149] In the following steps, the inventors performed modification site detection on an existing drug on the market and the urate oxidase obtained in the Example.
[0150] The PEG modification sites of polyethylene glycol-modified urate oxidase can be detected by first performing enzyme digestion of the non-pegylated and pegylated urate oxidases with one or more enzymes and then performing chromatographic detection to obtain a chromatogram, i.e., peptide map for determination. The non-pegylated and pegylated urate oxidases can be digested through single-enzyme digestion (Lys-C or Trypsin) and/or double-enzyme digestion (Lys-C and Trypsin combined). The digested enzyme fragments were separated by reversed-phase column, and the modification sites of polyethylene glycol-modified urate oxidase and the PEG modification percentage of the sites were calculated by the internal reference peptide fragment correction and comparison of the disappearance or reduction proportion of the peptide fragments.
[0151] Modification site analysis principle of trypsin and Lys-C double enzyme digestion quality peptide map: Lys-C can specifically digest the C-terminal of lysine (K); trypsin takes the basic amino acids, i.e., arginine (R) and lysine (K), as restriction enzyme cutting sites, and specifically digests the C-terminal peptide bond. Comparing the changes of the corresponding peptide fragments before and after digestion in PHC and PU5, and with reference to the internal standard peptide fragments, the relative proportion of the reduction or disappearance of the PEG-modified peptide fragments can be analyzed and determined. Through the relative proportion of the reduction or disappearance of the peptide fragment, a relative percentage of PEG modification at the lysine site on the peptide fragment can be determined, thereby determining whether a specific amino acid (e.g., lysine) on a specific peptide fragment is modified by PEG.
[0152] Details as follows: [0153] (1) Sample processing: urate oxidase and pegylated urate oxidase were taken and respectively diluted to 1 mg/mL with enzyme digestion buffer (25 mmol/L Tris-HCl, 20% acetonitrile, pH 9.0), and 100 μl of each dilute solution was taken, added with 2 μL of Lys-C, and digested at 37° C. for 4 hours. Subsequently, the solution was transferred to a pancreatin reaction tube (in a ratio of 1:100), digestion was continued at 37° C. for 2 hours, 4 μL of TCEP reducing solution was added, the reaction continued for 30 minutes, and then 10 μL of 1 mol/L hydrochloric acid solution was added to terminate the reaction.
[0154] (2) Analysis conditions: [0155] Instrument: Thermo Ultimate 3000 HPLC and MSQ Plus; [0156] Chromatographic column: Welch Materials μltimate®gXB-C18 (4.6 mm×250 mm, 5 μm), Welch; [0157] Analysis conditions: A solution (aqueous solution containing 0.1% TFA), solution B (acetonitrile solution containing 0.1% TFA); [0158] Gradient: 0 to 70 min, B from 3 to 70%; [0159] LC detection wavelength: 214 nm; [0160] Ion source: ESI; [0161] Ion type: positive ion; [0162] Cone voltage: 50V; [0163] Scanning range: 300 to 2000 Da; [0164] Scan time: 1 s; [0165] Post column flow splittered to MS: about 0.3 mL/min. [0166] 100 μL of the sample was injected, and the chromatogram was recorded.
[0167] (3) Results processing: [0168] The chromatograms (peptide maps) of urate oxidase and pegylated urate oxidase were compared, and the relative proportion of area reduction of the differential peptide fragments.
[0169] (4) The experimental results are shown in Table 5 to Table 8, and
TABLE-US-00007 TABLE 5 List of peptide fragments of PHC after digestion with Lys-C Theoretical Measured Peptide Digestion molecular molecular fragment site Sequence weight (Da) weight T1 3 TYK 410.47 410.2 T2 4 K 146.189 / T3 17 NDEVEFVRTGYGK 1513.627 / T2 + T3 KNDEVEFVRTGYGK 1641.089 1642.2 T4 21 DMIK 505.63 505.4 T5 30 VLHIQRDGK 1065.241 1065 T6 35 YHSIK 646.744 646.5 T7 48 EVATTVQLTLSSK 1376.57 / T8 49 K 146.189 / T9 66 DYLHGDNSDVIPTDTIK 1903.032 1903 T10 74 NTVNVLAK 858.005 857.7 T11 76 FK 293.366 293.1 T12 79 GIK 316.401 316.2 T13 97 SIETFAVTICEHFLSSFK 2059.364 2059 T14 112 HVIRAQVYVEEVPWK 1853.154 1852.8 T15 116 RFEK 578.669 578.4 T16 120 NGVK 416.478 417.2 T17 152 HVHAFIYTPTGTHFCEVE 3586.088 3586.2 QIRNGPPVIHSGIK T18 155 DLK 374.437 374.1 T19 158 VLK 358.481 358.2 T20 169 TTQSGFEGFIK 1214.34 1213.8 T21 179 DQFTTLPEVK 1177.32 1176.8 T22 190 DRCFATQVYCK 1333.543 1333.2 T23 215 WRYHQGRDVDFEATWD 3106.45 3106.5 TVRSIVLQK T24 222 FAGPYDK 796.878 796.5 T25 231 GEYSPSVQK 994.069 993.7 T26 266 TLYDIQVLTLGQVPEIED 4046.66 4046.1 MEISLPNIHYLNIDMSK T27 272 MGLINK 674.856 T28 285 EEVLLPLDNPYGK 1486.685 1486.6 T27 + MGLINK 2143.54 2143.2 T28 EEVLLPLDNPYGK T29 291 ITGTVK 617.743 617.4 T30 293 RK 302.377 T31 298 LSSRL 574.678 574.4
TABLE-US-00008 TABLE 6 List of peptide fragments of PHC after double-enzyme digestion with Lys- C and trypsin Theoretical relative Measured Peptide Sequence molecular weight molecular fragment position Sequence [Da] weight T1 1-3 TYK 410.470 410.3 T2 4 K 146.189 / T3 5-12 NDEVEFVR 1007.068 / T2 + 3 4-12 KNDEVEFVR 1135.4 T4 13-17 TGYGK 524.574 524.5 T5 18-21 DMIK 505.630 505.5 T6 22-27 VLHIQR 764.926 764.8 T7 28-30 DGK 318.330 / T8 31-35 YHSIK 646.744 646.7 T9 36-48 EVATTVQLTLSSK 1376.570 / T10 49 K 146.189 / T11 50-66 DYLHGDNSDVIPTDTIK 1903.032 1903.4 T12 67-74 NTVNVLAK 858.005 857.9 T13 75-76 FK 293.366 293.1 T14 77-79 GIK 316.401 / T15 80-97 SIETFAVTICEHFLSSFK 2059.364 2059.6 T16 98-101 HVIR 523.636 523.6 T17 102-112 AQVYVEEVPWK 1347.534 1347.4 T18 113 R 174.203 / T19 114-116 FEK 422.481 / T18 + 19 113-116 RFEK 578.684 578.6 T20 117-120 NGVK 416.478 417.1 T21 121-141 HVHAFIYTPTGTHFCEVEQ 2485.802 2486.8 T22 142-152 NGPPVIHSGIK 1118.301 1118.8 T21 + 22 121-152 3586.103 3587.7 T23 153-155 DLK 374.437 / T24 156-158 VLK 358.481 358.3 T25 159-169 TTQSGFEGFIK 1214.340 1214.2 T26 170-179 DQFTTLPEVK 1177.320 1177.2 T27 181-181 DR 289.291 / T28 182-190 CFATQVYCK 1062.267 / T27 + 28 181-190 1333.558 1333.6 T29 191-192 WR 360.416 360.1 T30 193-197 YHQGR 659.702 659.6 T31 198-209 DVDFEATWDTVR 1453.528 1453.6 T32 210-215 SIVLQK 686.850 686.8 T33 216-222 FAGPYDK 796.878 796.8 T34 223-231 GEYSPSVQK 994.069 994.1 T35 262-266 TLYDIQVLTLGQVPEIEDM 4046.660 4047 EISLPNIHYLNIDMSK T36 267-272 MGLINK 674.856 674.7 T37 273-285 EEVLLPLDNPYGK 1486.685 1486.7 T36 + 37 2143.541 2143.6 T38 286-291 ITGTVK 617.743 617.7 T39 292 R 174.203 / T40 293 K 146.189 / T41 294-297 LSSR 461.519 461.5 T42 298 L 131.175 /
[0170] The calculation method of the reduction percentage of peak area of PU5 peptide fragments is as follows:
[0171] The following formula can be used to calculate the corresponding peak areas of PU5 peptide fragments at the concentration of PU5 same as the concentration of PHC:
A.sub.1=A.sub.0×t
[0172] where A.sub.1 is a peak area of PU5 peptide fragments converted with two internal reference peptides, A.sub.0 is a measured peak area of peptide fragments of a PU5 peptide map, and t is an average value of a peak area ratio of T30 internal reference peptide fragment in the PHC peptide map to T30 internal reference peptide fragment in the PU5 peptide map and a peak area ratio of T31 internal reference peptide fragment in the PHC peptide map to T31 internal reference peptide fragment in the PU5 peptide map, that is, t is 0.588.
TABLE-US-00009 TABLE 7 Comparison of PHC and PU5 internal reference peptide fragments Peptide PHC peptide map PU5 peptide map Peak area ratio No. Retention Peak Retention Peak of PHC to PU5 fragment Sequence time area time area Value Mean T30 YHQGR 7.5 13.4 7.467 22.9 0.585 0.588 T31 DVDFEATWDTVR 28.31 35.5 28.28 60.1 0.591
[0173] With the peak area of peptide fragment converted with the internal reference and the peak area of PHC peptide map, the relative percentage of the reduction of the peak area of a certain peptide in the PU5 peptide map can be calculated based on the following equation:
P(%)=(A.sub.2−A.sub.1)/A.sub.2×100%
[0174] where A.sub.2 is a peak area of a certain peptide fragment in the PHC peptide map, and A.sub.1 is a peak area of this peptide fragment in PU5 converted with internal reference.
TABLE-US-00010 TABLE 8 Summary results of peptide fragments with reduced peak area in the peptide map after PU5 was digested with double enzymes. Relative proportion Peptide of reduced peak fragment area of peptide position Peptide fragment sequence fragment 1-3 TYK 100.00% 4-12 KNDEVEFVR 94.07% 31-35 YHSIK 100.00% 75-76 FK 82.27% 80-97 SIETFAVTICEHFLSSFK 100.00% 102-112 AQVYVEEVPWK 100.00% 113-116 RFEK 100.00% 117-120 NGVK 100.00% 121-152 HVHAFIYTPTGTHFCEVEQIRNGPPVIHSGIK 100.00% 193-197 YHQGR Internal reference peptide fragment 198-209 DVDFEATWDTVR Internal reference peptide fragment 216-222 FAGPYDK 91.37% 223-231 GEYSPSVQK 86.40% 232-266 TLYDIQVLTLGQVPEIEDMEISLPNIHYLNIDMSK 100.00% 273-285 EEVLLPLDNPYGK 100.00%
[0175] Based on the analysis of the protein sequence (SEQ ID NO: 1) of the present example, the potential sites for urate oxidase modification include 31 sites, including T.sup.1, K.sup.3, K.sup.4, K.sup.30, K.sup.35, K.sup.76, K.sup.79, K.sup.97, K.sup.112, K.sup.116, K.sup.120, K.sup.152, K.sup.179, K.sup.222, K.sup.231, K.sup.266, K.sup.272, K.sup.285, K.sup.291, and K.sup.293.
[0176] Based on the analysis of the modification sites of polyethylene glycol-modified urate oxidase obtained in Example 2, as shown in Table 5, Table 6, Table 7, Table 8 and
[0177] Moreover, the inventors found that the polyethylene glycol-modified urate oxidase of the present disclosure has more modification sites than the marketed drug, and has significant differences. For example, through single enzyme digestion, it was found that the disappearance ratio of the peptide fragments where the four sites K.sup.30, K.sup.35, K.sup.222, and K.sup.231 are located in the polyethylene glycol-modified urate oxidase of the present disclosure is more than 80%, while the peptide fragments of the marketed analogous drug where these four sites are located hardly disappeared, that is, the modification rate of the marketed analogous drug at the four sites K.sup.30, K.sup.35, K.sup.222, and K.sup.231 is much lower than that of the polyethylene glycol-modified urate oxidase of the present disclosure. In addition, the polyethylene glycol-modified urate oxidase of the present disclosure has significantly lower immunogenicity than the marketed drug, which may be related to the differences in the number of modification sites and the modification sites according to Applicant's speculation.
[0178] The in vivo evaluation of the polyethylene glycol-modified urate oxidase (PU5) of the present disclosure in animals will be described in detail as below. The pegloticase used in the experiment refers to the analogous drug on the market with a batch number 5085B.
EXAMPLE 4 STUDY ON IN VIVO PHARMACODYNAMICS OF POLYETHYLENE GLYCOL-MODIFIED URATE OXIDASE
4.1. In Vivo Efficacy Evaluation of Polyethylene Glycol-Modified Urate Oxidase in Model Rats
[0179] A chronic hyperuricemia rat model was induced by potassium oxazinate drinking water in combination with high uric acid feed, to evaluate the therapeutic effect of polyethylene glycol-modified urate oxidase (PU5) on chronic hyperuricemia in rats.
[0180] 40 model rats were selected and randomly divided into 4 groups, i.e., a model group, a low-dose pegylated uricase administration group (0.3 mg/kg), a medium-dose pegylated uricase administration group (1.0 mg/kg), and a high-dose pegylated uricase administration group (3.0 mg/kg), 10 rats in each group; and additionally, 10 normal SD rats were selected as the blank control group. The model-establishing experiment was conducted for 5 consecutive weeks, and intramuscular administration was started 1 week after the start of the model establishing. The administration was performed and continued once a week for 4 consecutive weeks. The levels of serum uric acid, serum urea nitrogen, and serum creatinine of rats before the administration and 7 days after each administration were detected, and the histological changes of rat kidneys were observed after the experiment.
[0181] The results in
4.2 Evaluation of Single Administration of Polyethylene Glycol-Modified Urate Oxidase in Rats
[0182] 36 SD rats (half females and half males) were randomly divided into 6 groups (see Table 9), namely, a marketed drug Pegloticase intravenous injection group, a Pegloticase intramuscular injection group, a polyethylene glycol-modified urate oxidase intravenous injection group, as well as low-dose, medium-dose and high-dose polyethylene glycol-modified urate oxidase intramuscular injection groups (0.5 mg/kg, 1.0 mg/kg, 2.0 mg/kg). The specific administration regimens and doses are shown in Table 9. PK and PD were detected by taking the blood from the jugular vein.
TABLE-US-00011 TABLE 9 Animal grouping and dose design Administration Administration Administration Number of Administration Administration dose concentration volume animals No Group route frequency (mg/kg) (mg/ml) (ml/kg) M F 1 Pegloticase Intravenous One time 1.0 0.1 10.0 3 3 intravenous injection injection group 2 Pegloticase Intramuscular One time 1.0 1.0 1.0 3 3 intramuscular injection injection group 3 PU5 intravenous Intravenous One time 1.0 0.1 10.0 3 3 injection group injection 4 PU5 low-dose Intramuscular One time 0.5 0.5 1.0 3 3 intramuscular injection injection group 5 PU5 medium- Intramuscular One time 1.0 1.0 1.0 3 3 dose injection intramuscular injection group 6 PU5 high-dose Intramuscular One time 2.0 2.0 1.0 3 3 intramuscular injection injection group
4.2.1. Pharmacokinetic Comparison
[0183] All the SD rats, before the administration, each had a serum drug concentration level lower than the lower limit of quantification (LLOQ: 312.500 ng/mL), and after one single intramuscular injection of 0.5 mg/kg, 1.0 mg/kg, and 2.0 mg/kg of the drug , in a period from Oh to 168 h (0 to 7 days), the serum drug concentration of the pegylated uricase injection (PU5) was dose-dependent and had an overall level increasing with the increase in the administered dose; and 168 hours later, the blood drug concentration of the pegloticase intramuscular administration group was lower than the lower limit of quantification, and the blood drug concentration of the PU5 intramuscular administration group maintained for more than 240 h.
[0184] After administration, for each group of 1.0 mg/kg Pegloticase intravenous injection and intramuscular injection groups, 1.0 mg/kg pegylated uricase intravenous injection group, as well as 0.5 mg/kg, 1.0 mg/kg, and 2.0 mg/kg pegylated uricase intramuscular injection groups, a ratio of Cmax (C5min) of female SD rats to male SD rats was in the range of 0.75 to 0.99, a ratio of AUClast of female SD rats to male SD rats was in the range of 0.54 to 0.94, and a ratio of AUC0-∞ of female SD rats to male SD rats was in the range of 0.58 to 0.97. It can be seen that there is no significant gender difference in the exposure levels of Pegloticase and the pegylated uricase (PU5) injections in SD rats.
[0185] However, when the SD rats were administered with the same dose (1.0 mg/kg), AUClast of the marketed drug Pegloticase intravenous administration group was 426.48±65.34, AUClast of the Pegloticase intramuscular injection group was 264.19±78.22; and AUClast of the PU5 injection intravenous administration group was 565.61±161.60, the AUClast of the PU5 intramuscular injection group was 337.86±227.34. Under the same dose and administration mode, the AUClast of PU5 was higher than that of the marketed drug Pegloticase.
[0186] When the SD rats were administered with the same dose (1.0 mg/kg), t½ (h) of the marketed drug Pegloticase intravenous administration group was 49.51±8.12, t½ (h) of the Pegloticase intramuscular administration group was 55.21±13.50, t½ (h) of the PU5 injection intravenous administration group was 86.12±33.82, and the t½ (h) of the PU5 intramuscular administration group was 60.45±21.37. Under the same dose and administration mode, the t½ (h) of PU5 was longer than that of the marketed drug Pegloticase.
[0187] The above pharmacokinetic results are shown in Tables 10 to 15, and
TABLE-US-00012 TABLE 10 Individual blood drug concentration data and statistical analysis data when the SD rats received a single intravenous injection of 1.0 mg/kg Pegloticase (unit: μg/mL) Sampling Male Female Female + Male time (h) 1M001 1M002 1M003 N Mean SD 1F001 1F002 1F003 N Mean SD N Mean SD 0 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 0.08333 8.03 7.466 8.078 3 7.858 0.340 6.495 6.402 7.828 3 6.908 0.798 6 7.383 0.756 0.5 8.042 7.352 7.926 3 7.773 0.369 6.257 6.141 7.618 3 6.672 0.821 6 7.223 0.830 2 5.917 7.235 6.914 3 6.689 0.687 6.056 5.875 6.836 3 6.256 0.511 6 6.472 0.591 4 7.598 7.047 6.757 3 7.134 0.427 5.595 4.922 7.164 3 5.894 1.150 6 6.514 1.031 8 7.144 5.852 6.492 3 6.496 0.646 5.005 4.121 5.748 3 4.958 0.815 6 5.727 1.069 24 4.992 3.923 4.469 3 4.461 0.535 3.764 3.341 4.862 3 3.989 0.785 6 4.225 0.654 48 3.552 2.934 3.304 3 3.263 0.311 2.988 2.415 3.836 3 3.080 0.715 6 3.172 0.503 72 3.009 2.271 2.422 3 2.567 0.390 2.223 1.994 3.103 3 2.440 0.585 6 2.504 0.450 120 1.522 1.483 1.246 3 1.417 0.149 0.985 1.098 1.734 3 1.272 0.404 6 1.345 0.284 168 0.652 0.629 0.316 3 0.532 0.188 0.497 0.672 0.726 3 0.632 0.120 6 0.582 0.151 240 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 336 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / Notes: “/” means no relevant information.
TABLE-US-00013 TABLE 11 Individual blood drug concentration data and statistical analysis data when the SD rats received a single intravenous injection of 1.0 mg/kg pegylated uricase (unit: μg/mL) Sampling Male Female Female + Male time (h) 3M001 3M002 3M003 N Mean SD 3F001 3F002 3F003 N Mean SD N Mean SD 0 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 0.08333 7.364 9.941 7.74 3 8.348 1.392 7.236 5.991 6.657 3 6.628 0.623 6 7.488 1.348 0.5 7.316 9.469 7.693 3 8.159 1.150 7.051 5.513 6.36 3 6.308 0.770 6 7.234 1.340 2 7.742 9.084 7.338 3 8.055 0.914 6.063 5.522 6.44 3 6.008 0.461 6 7.032 1.294 4 7 8.837 6.997 3 7.611 1.061 6.508 5.735 6.288 3 6.177 0.398 6 6.894 1.064 8 6.628 7.43 6.61 3 6.889 0.468 5.387 4.85 5.52 3 5.252 0.355 6 6.071 0.971 24 4.672 5.628 4.746 3 5.015 0.532 4.291 3.919 4.129 3 4.113 0.187 6 4.564 0.609 48 3.307 4.264 3.497 3 3.689 0.507 3.406 3.042 3.014 3 3.154 0.219 6 3.422 0.456 72 2.933 3.762 3.124 3 3.273 0.434 2.859 2.596 2.319 3 2.591 0.270 6 2.932 0.494 120 1.986 2.279 1.989 3 2.085 0.168 1.604 1.617 1.454 3 1.558 0.091 6 1.822 0.313 168 1.268 1.742 1.391 3 1.467 0.246 1.187 1.031 0.699 3 0.972 0.249 6 1.220 0.350 240 0.67 1.19 0.734 3 0.865 0.284 BLQ BLQ BLQ 0 / / 3 0.865 0.284 336 BLQ 0.853 0.368 2 0.611 0.343 BLQ BLQ BLQ 0 / / 2 0.611 0.343 Notes: “/” means no relevant information.
TABLE-US-00014 TABLE 12 Individual blood drug concentration data and statistical analysis data when the SD rats received a single intramuscular injection of 1.0 mg/kg Pegloticase (unit: μg/mL) Sampling Male Female Female + Male time (h) 2M001 2M002 2M003 N Mean SD 2F001 2F002 2F003 N Mean SD N Mean SD 0 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 0.5 0.652 BLQ 0.581 2 0.617 0.050 0.388 BLQ BLQ 1 0.388 / 3 0.540 0.137 2 1.337 1.249 1.62 3 1.402 0.194 1.172 1.135 BLQ 2 1.154 0.026 5 1.303 0.194 4 2.298 1.699 2.348 3 2.115 0.361 1.812 1.371 0.773 3 1.319 0.521 6 1.717 0.593 8 2.56 2.058 2.396 3 2.338 0.256 1.915 1.657 1.273 3 1.615 0.323 6 1.977 0.474 24 3.808 3.235 3.309 3 3.451 0.312 2.947 2.808 2.493 3 2.749 0.233 6 3.100 0.456 48 3.188 2.618 2.749 3 2.852 0.299 2.317 2.279 1.729 3 2.108 0.329 6 2.480 0.495 72 2.694 2.263 2.211 3 2.389 0.265 1.984 2.016 1.261 3 1.754 0.427 6 2.072 0.471 120 1.56 1.169 1.332 3 1.354 0.196 0.884 1.111 0.174 3 0.723 0.489 6 1.038 0.480 168 BLQ 0.341 0.869 2 0.605 0.373 BLQ 0.635 BLQ 1 0.635 / 3 0.615 0.265 240 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 336 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / Note: “/” means no relevant information.
TABLE-US-00015 TABLE 13 Individual blood drug concentration data and statistical analysis data when the SD rats received a single intramuscular injection of 1.0 mg/kg pegylated uricase (unit: μg/mL) Sampling Male Female Female + Male time (h) 5M001 5M002 5M003 N Mean SD 5F001 5F002 5F003 N Mean SD N Mean SD 0 BLQ BLQ BLQ 0 / / BLQ BLQ BLQ 0 / / 0 / / 0.5 BLQ 1.421 0.328 2 0.875 0.773 BLQ BLQ BLQ 0 / / 2 0.875 0.773 2 BLQ 2.295 0.923 2 1.609 0.970 0.593 0.905 0.674 3 0.724 0.162 5 1.078 0.695 4 0.729 2.897 1.648 3 1.758 1.088 1.356 1.222 0.762 3 1.113 0.312 6 1.436 0.798 8 1.305 3.628 2.054 3 2.329 1.186 1.559 1.249 1.266 3 1.358 0.174 6 1.844 0.926 24 2.408 4.617 3.069 3 3.365 1.134 3.01 2.339 2.216 3 2.522 0.427 6 2.943 0.895 48 2.068 3.877 2.4 3 2.782 0.963 2.739 2.298 2.189 3 2.409 0.291 6 2.595 0.668 72 1.76 3.606 2.027 3 2.464 0.998 2.385 1.761 1.863 3 2.003 0.335 6 2.234 0.712 120 1.042 2.9 1.107 3 1.683 1.054 1.169 0.811 0.926 3 0.969 0.183 6 1.326 0.782 168 0.479 2.419 0.631 3 1.176 1.079 0.595 BLQ BLQ 1 0.595 / 4 1.031 0.928
TABLE-US-00016 TABLE 14 Average pharmacokinetic parameters of SD rats after a single intravenous injection of Pegloticase and pegylated uricase injections Dose t.sub.1/2 C.sub.5 min AUC.sub.last AUC.sub.0-∞ V.sub.z Cl MRT.sub.last (mg/kg) Gender Parameter (h) (μg/mL) (h * /mL) (h * μg/mL) (mL/kg) (mL/h/kg) (h) 1.0 Male N 3 3 3 3 3 3 3 (Pegloticase) Mean 45.70 7.86 448.57 484.58 136.90 2.08 52.36 SD 7.57 0.34 42.16 46.96 26.57 0.19 2.58 Female N 3 3 3 3 3 3 3 Mean 53.32 6.91 404.38 453.63 173.91 2.26 54.64 SD 7.98 0.80 86.21 90.21 43.64 0.40 2.62 Female + Male N 6 6 6 6 6 6 6 Mean 49.51 7.39 426.48 469.11 155.40 2.17 53.50 SD 8.12 0.76 65.34 66.52 38.14 0.30 2.64 1.0 Male N 3 3 3 3 3 3 3 (PU5) Mean 105.16 8.35 692.29 794.77 186.76 1.31 90.87 SD 41.08 1.39 128.22 197.50 24.94 0.29 14.06 Female N 3 3 3 3 3 3 3 Mean 67.09 6.63 438.93 535.17 180.63 1.88 58.58 SD 9.24 0.62 26.51 59.13 11.64 0.21 2.76 Female + Male N 6 6 6 6 6 6 6 Mean 86.12 7.49 565.61 664.97 183.70 1.59 74.73 SD 33.82 1.35 161.60 192.92 17.73 0.39 19.87
TABLE-US-00017 TABLE 15 Average pharmacokinetic parameters of SD rats after a single intramuscular injection of Peglocticase and pegylated uricase injections Dose t.sub.1/2 T.sub.max C.sub.max AUC.sub.last AUC.sub.0-∞ Vz_F Cl_F MRT.sub.last (mg/kg) Gender Parameter (h) (h) (μg/mL) (h * μg/mL) (h * μg/mL) (mL/kg) (mL/h/kg) (h) 1.0 Male N 3 3 3 3 3 3 3 3 (Pegloticase) Mean 58.31 24.00 3.45 318.23 405.13 203.75 2.54 60.57 SD 20.10 0.00 0.31 15.37 80.13 42.90 0.54 6.54 Female N 3 3 3 3 3 3 3 3 Mean 52.12 24.00 2.75 210.14 278.56 276.83 3.72 51.27 SD 4.78 0.00 0.23 79.35 60.90 50.57 0.91 15.28 Female + Male N 6 6 6 6 6 6 6 6 Mean 55.21 24.00 3.10 264.19 341.85 240.29 3.13 55.92 SD 13.50 0.00 0.46 78.22 94.12 57.97 0.93 11.68 0.5 Male N 3 3 3 3 3 3 3 3 (PU5) Mean 63.57 24.00 1.93 181.10 233.11 199.06 2.21 60.26 SD 18.68 0.00 0.26 79.19 48.71 56.50 0.45 23.89 Female N 3 3 3 3 3 3 3 3 Mean 48.20 24.00 1.91 170.63 205.87 167.09 2.56 55.67 SD 17.38 0.00 0.14 41.99 61.41 21.47 0.67 11.48 Female + Male N 6 6 6 6 6 6 6 6 Mean 55.88 24.00 1.92 175.87 219.49 183.07 2.38 57.97 SD 18.20 0.00 0.19 56.98 51.77 42.05 0.54 16.95 1.0 Male N 3 3 3 3 3 3 3 3 (PU5) Mean 70.47 24.00 3.36 439.83 504.61 225.86 2.57 84.20 SD 28.55 0.00 1.13 307.66 344.91 54.21 1.32 31.10 Female N 3 3 3 3 3 3 3 3 Mean 50.44 24.00 2.52 235.90 293.04 252.46 3.46 58.28 SD 5.05 0.00 0.43 58.01 45.24 46.82 0.50 6.96 Female + Male N 6 6 6 6 6 6 6 6 Mean 60.45 24.00 2.94 337.86 398.83 239.16 3.02 71.24 SD 21.37 0.00 0.89 227.34 248.66 47.59 1.02 24.65 2.0 Male N 3 3 3 3 3 3 3 3 (PU5) Mean 66.65 24.00 4.84 590.58 649.31 292.61 3.10 85.42 SD 20.11 0.00 0.46 59.68 55.26 64.39 0.27 19.91 Female N 3 3 3 3 3 3 3 3 Mean 72.51 32.00 4.55 537.05 628.72 339.98 3.22 79.26 SD 15.56 13.86 0.91 124.85 78.17 100.19 0.42 9.60 Female + Male N 6 6 6 6 6 6 6 6 Mean 69.58 28.00 4.70 563.81 639.01 316.30 3.16 82.34 SD 16.40 9.80 0.66 92.30 61.59 79.67 0.32 14.38
4.2.2. Comparison of In Vivo Efficacy (Uric Acid)
[0188] After a single intramuscular injection of 0.5 mg/kg, 1.0 mg/kg, 2.0 mg/kg pegylated uricase injection, the uric acid concentration maintained at a low level 1 day and 3 days after the administration, the uric acid level of each dose group began to recover 7 days after the administration, and the higher the dose, the longer the uric acid maintained a lower level in the body. Comparing the intravenous injection groups of the same dose, the PU5 intravenous injection group maintained a low concentration level of serum uric acid for a longer time than the pegloticase intravenous injection group. Comparing the intramuscular injection groups of the same dose, the PU5 intramuscular injection group maintained a low concentration level of serum uric acid for a longer time than the pegloticase intramuscular injection group. Comparing the groups of the same dose, the PU5 intravenous or intramuscular injection group maintained a low concentration level of serum uric acid for a longer time than the pegloticase intravenous or intramuscular injection group, that is, PU5 maintained a low concentration level of uric acid in the body for a longer time than pegloticase in each case. The results are illustrated in
4.3 Evaluation of Multiple Administrations of Polyethylene Glycol-Modified Urate Oxidase in Rats
[0189] In this experiment, 4 groups were set, i.e., a marketed drug Pegloticase intravenous injection group, a Pegloticase intramuscular injection group, a pegylated uricase (PU5) intravenous injection group, and a PU5 intramuscular injection group, each group included 8 rats, four of which were male and the other four of which were female, 32 SD rats in total. The Pegloticase and pegylated uricase intravenous injection groups adopted intravenous injection; and the Pegloticase and pegylated uricase intramuscular injection groups adopted intramuscular injection. The administration dose was 1.0 mg/kg, once a week, for 4 consecutive times.
[0190] The result analysis indicates that:
[0191] SD rats were injected intravenously/intramuscularly with 1.0 mg/kg Pegloticase and pegloticase injections for multiple times, The general condition of the rats had no abnormal changes related to the drugs.
4.3.1 Anti-PEG Antibody Detection
[0192] SD rats were administrated for 4 consecutive times. Before the first administration, no anti-PEG antibodies and no anti-PHC antibodies were detected in either individual animal; after the administration, no anti-PHC antibodies were detected in either animal, anti-PEG antibodies were detected in each group of the Pegloticase intravenous and intramuscular injection groups as well as the pegylated uricase intravenous and intramuscular injection groups, and the ratios of positive results were: 3/8, 1/8, 1/8, and 1/8, respectively. The PEG immunohistochemical examination revealed that the spleen, liver and kidney of the pegloticase intravenous and intramuscular injection groups showed weak positive expression of PEG; and no positive expression of PEG was found in the pegylated uricase intravenous and intramuscular injection groups. The results are shown in Table 16.
[0193] From the above analysis, it can be seen that the antibodies induced by PU5 and pegloticase are mainly antibodies against the PEG part, rather than antibodies against the urate oxidase part.
[0194] According to the results of PEG antibody and PEG immunohistochemistry, the intramuscular administration groups of both PU5 and pegloticase are superior to the intravenous administration groups thereof. Among them, regarding the produced anti-PEG antibodies of the intravenous administration groups, PU5 is superior to pegloticase; and regarding the produced anti-PEG antibodies of the intramuscular administration groups, PU5 is superior to pegloticase.
TABLE-US-00018 TABLE 16 PEG immunohistochemistry positive expression results Incidence Pegloticase Pegloticase PU5 PU5 intravenous intramuscular intravenous intramuscular Microscopic injection group injection Group injection group injection group observation Male Female Male Female Male Female Male Female Spleen Total inspection number: 4 4 4 4 4 4 4 4 PEG, white pulp 1 0 1 1 2 0 0 0 0 Total incidence number: 0 1 1 2 0 0 0 0 PEG, red pulp 1 0 1 0 0 0 0 0 0 Total incidence number: 0 1 0 0 0 0 0 0 Liver Total inspection number: 4 4 4 4 4 4 4 4 PEG, vascular 1 4 4 1 3 0 0 0 0 endothelial cells/ Kupffer cells Total incidence number: 4 4 1 3 0 0 0 0 Kidney Total inspection number: 4 4 4 4 4 4 4 4 PEG, renal tubules 1 3 1 1 1 0 0 0 0 Total incidence number: 3 1 1 1 0 0 0 0 PEG, vascular 1 0 1 0 0 0 0 0 0 endothelial cells Total incidence number: 0 1 0 0 0 0 0 0 Positive grading: 1 = extremely weakly positive, 2 = weakly positive, 3 = moderately positive, 4 = strongly positive.
4.3.2 Pharmacokinetic Tests
[0195] The SD rats that had received multiple intravenous and intramuscular injections of Pegloticase and pegylated uricase injections exhibited no significant gender difference in the main pharmacokinetic parameters between the groups. After 4 consecutive administrations, these two drugs accumulated slightly in rats.
[0196] When the SD rats received multiple intravenous/intramuscular injection administrations with the same dose (1.0 mg/kg) of the marketed drug Pegloticase, the absolute bioavailability in the rats was 51.35% after the first administration; and the absolute bioavailability in the rats was 45.98% after the last administration. When the SD rats received multiple intravenous/intramuscular injection administrations with the same dose (1.0 mg/kg) of the pegylated uricase injection, the absolute bioavailability in the rats was 58.29% after the first administration; and the absolute bioavailability in the rats was 52.60% after the last administration.
4.3.3 Comparison of In Vivo Drug Efficacy (Uric Acid)
[0197] SD rats were injected intravenously and intramuscularly with 1.0 mg/kg Pegloticase and 1.0 mg/kg pegylated uricase injection for 4 consecutive times (1 time/week), the serum uric acid concentration maintained at a low level after each administration; the serum uric acid concentration recovered 14 days after the last administration in the Pegloticase intramuscular injection group, and in the rest groups, the serum uric acid concentration recovered 18 days after the last administration. Compared with the same dose of the marketed drug Pegloticase, the maintaining time in the intravenous injection groups of these two drugs was basically consistent, and the maintaining time of the pegylated uricase intramuscular injection group was longer than that of the marketed drug intramuscular injection group. That is, for the intramuscular administration, the efficacy of PU5 is superior than that of Pegloticase.
[0198] The above results are shown in Table 17 to Table 20, and
TABLE-US-00019 TABLE 17 Results of average pharmacokinetic parameters after continuous intravenous injection of Pegloticase and a pegylated uricase injection in SD rats Experiment Dose t.sub.1/2 T.sub.max C.sub.max AUC.sub.last AUC.sub.0-∞ Vz Cl MRT.sub.last time Drug name Gender Parameter (h) (h) (μg/mL) (h * μg/mL) (h * μg/mL) (mL/kg) (mL/h/kg) (h) Day 1 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 Pegloticase Mean 72.17 2.13 11.12 632.58 778.65 133.74 1.29 56.91 SD 4.53 1.44 0.28 25.32 45.00 4.49 0.07 1.17 Female N 4 4 4 4 4 4 4 4 Mean 66.24 0.50 8.84 514.21 633.80 149.07 1.59 54.93 SD 17.91 0.00 1.07 50.98 64.84 27.23 0.16 7.58 Female + N 8 8 8 8 8 8 8 8 Male Mean 69.21 1.31 9.98 573.40 706.22 141.41 1.44 55.92 SD 12.51 1.28 1.42 73.43 93.08 19.84 0.20 5.13 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 PU5 Mean 67.98 1.75 9.47 527.73 634.48 158.66 1.60 55.50 SD 8.87 1.66 0.91 91.07 91.12 39.53 0.22 0.89 Female N 4 4 4 4 4 4 4 4 Mean 79.29 1.38 6.42 369.05 481.09 238.12 2.16 59.68 SD 17.07 1.75 0.61 49.11 98.31 15.34 0.53 2.84 Female + N 8 8 8 8 8 8 8 8 Male Mean 73.63 1.56 7.94 448.39 557.79 198.39 1.88 57.59 SD 13.97 1.59 1.78 108.54 120.10 50.74 0.48 2.96 Day 22 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 Pegloticase Mean 135.63 1.75 12.33 1159.18 1300.99 149.28 0.78 118.29 SD 40.45 1.66 0.94 134.20 208.65 28.13 0.13 9.91 Female N 4 4 4 4 4 4 4 4 Mean 96.09 0.88 8.02 672.95 747.61 186.89 1.35 92.46 SD 7.69 0.75 0.87 78.50 78.66 24.21 0.14 9.52 Female + N 8 8 8 8 8 8 8 8 Male Mean 115.86 1.31 10.17 916.07 1024.30 168.09 1.07 105.37 SD 34.25 1.28 2.45 279.12 329.86 31.53 0.33 16.48 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 PU5 Mean 149.80 2.25 9.00 840.78 947.08 229.16 1.07 117.99 SD 24.68 2.02 0.73 91.96 104.82 36.69 0.11 6.88 Female N 4 4 4 4 4 4 4 4 Mean 103.90 1.25 6.63 576.81 636.52 236.33 1.63 101.66 SD 21.25 0.87 0.72 128.81 128.02 17.98 0.39 20.03 Female + N 8 8 8 8 8 8 8 8 Male Mean 126.85 1.75 7.82 708.79 791.80 232.75 1.35 109.82 SD 32.51 1.54 1.44 175.05 198.21 27.02 0.40 16.38
TABLE-US-00020 TABLE 18 Results of average pharmacokinetic parameters after continuous intramuscular injection of Pegloticase and pegylated uricase injection in SD rats Experiment Dose t.sub.1/2 T.sub.max C.sub.max AUC.sub.last AUC.sub.0-∞ Vz_F Cl_F MRT last time Drug name Gender Parameter (h) (h) (μg/mL) (h * μg/mL) (h * μg/mL) (mL/kg) (mL/h/kg) (h) Day 1 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 Pegloticase Mean 59.68 24.00 3.16 318.22 395.66 217.53 2.54 62.05 SD 13.70 0.00 0.38 29.92 29.26 49.49 0.19 6.59 Female N 4 4 4 4 4 4 4 4 Mean 80.53 24.00 2.80 270.69 415.60 282.07 2.48 57.80 SD 16.48 0.00 0.36 66.91 84.31 37.74 0.52 6.21 Female + N 8 8 8 8 8 8 8 8 Male Mean 70.11 24.00 2.98 294.46 405.63 249.80 2.51 59.92 SD 17.91 0.00 0.39 54.29 59.39 53.39 0.36 6.35 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 PU5 Mean 82.25 6.00 3.06 290.64 403.89 294.92 2.50 61.83 SD 9.79 2.31 0.25 34.67 48.73 29.13 0.31 6.88 Female N 4 4 4 4 4 4 4 4 Mean 70.44 48.00 2.21 232.11 306.59 340.32 3.50 66.28 SD 13.41 19.60 0.26 59.53 90.62 46.97 1.09 10.28 Female + N 8 8 8 8 8 8 8 8 Male Mean 76.34 27.00 2.63 261.38 355.24 317.62 3.00 64.06 SD 12.57 25.90 0.51 54.89 85.10 43.56 0.91 8.44 Day 22 1.0 mg/kg Male N 3 4 4 4 3 3 3 4 Pegloticase Mean 198.20 25.00 3.18 486.70 799.90 353.52 1.35 112.01 SD 83.85 18.00 0.85 298.21 293.71 23.56 0.42 60.30 Female N 4 4 4 4 4 4 4 4 Mean 97.92 20.00 2.69 355.77 427.75 344.97 2.65 94.51 SD 33.98 8.00 0.71 134.18 155.69 88.41 1.19 30.45 Female + N 7 8 8 8 7 7 7 8 Male Mean 140.90 22.50 2.93 421.23 587.25 348.64 2.09 103.26 SD 76.12 13.17 0.77 225.23 283.63 64.14 1.12 45.20 1.0 mg/kg Male N 4 4 4 4 4 4 4 4 PU5 Mean 140.04 15.00 2.52 395.82 478.83 610.95 9.64 102.76 SD 90.61 10.52 1.15 255.45 300.26 419.13 16.09 61.50 Female N 4 4 4 4 4 4 4 4 Mean 122.51 30.00 2.41 349.84 428.61 416.41 2.82 103.39 SD 59.33 12.00 0.50 178.08 204.30 72.32 1.36 44.91 Female + N 8 8 8 8 8 8 8 8 Male Mean 131.27 22.50 2.46 372.83 453.72 513.68 6.23 103.08 SD 71.52 13.17 0.82 205.33 239.26 297.23 11.18 49.85
TABLE-US-00021 TABLE 19 Statistical results of uric acid in each dose group after multiple intramuscular/intravenous injections of Pegloticase and a pegylated uricase injection in SD rats (Mean ± SD) 1.0 mg/kg 1.0 mg/kg 1.0 mg/kg 1.0 mg/kg Pegloticase Pegloticase PU5 PU5 Intravenous Intramuscular Intravenous Intramuscular Gender injection group injection group injection group injection group Detection time n
[0199] In the specification, descriptions with reference to the terms “an embodiment”, “some embodiments”, “examples”, “specific examples”, or “some examples”, etc., mean specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the above terms are illustrative, and do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine the different embodiments or examples and the features of the different embodiments or examples described in this specification without contradicting each other.