Antibody-related drugs can be used to treat major diseases such as malignant tumors, immune diseases, infectious or allergic diseases, blood or extracellular fluid diseases, and thus have attracted attention from across the world. Being the most active component of the biopharmaceutical industry, antibody-related drugs have become a diamond in the rough for future biopharmaceutical development.
With the continuous deepening of intellectual property strategies of encouraging innovation and the continuous strengthening of intellectual property protection and law enforcement in China, China has been recognized by life science companies as an extremely important biopharmaceutical market with significant growth potential. Patent protection is of great importance to the development of the pharmaceutical industry. What are the most frequently encountered challenges for biomedical companies in the process of seeking patent protections for antibody-related inventions? This article utilizes the latest case studies to help you better understand the examination practice of antibody-related patent applications in China.
I. Manner of definition of an antibody claim
For a patent application, an antibody-related claim is generally defined in a way as follows:
1. Defining an antibody by a domain or epitope of an antigen, for example: “an antibody that binds to domain B of protein A” or “an antibody that binds to epitope A”;
2. Defining an antibody by means of a CDR sequence: under this circumstance, six CDRs of heavy and light chains are generally simultaneously defined; the form thereof is such as “an antibody whose VH CDR1, CDR2 and CDR3 have the amino acid sequences of SEQ ID NOs: 1-3, respectively, and whose VL CDR1, CDR2 and CDR3 have the amino acid sequences of SEQ ID NOs: 4-6, respectively”;
3. Defining an antibody by means of the sequence of a heavy chain variable region (VH) and of a light chain variable region (VL): the form thereof is such as “an antibody whose VH has the amino acid sequence as set forth in SEQ ID NO: 1 and whose VL has the amino acid sequence as set forth in SEQ ID NO: 2”;
4. Defining a monoclonal antibody by means of hybridoma: the form thereof is such as “a monoclonal antibody produced by a hybridoma deposited under an accession number of xxx”;
5. Defining an antibody by means of its affinity or competive binding to a target: for example, “an antibody which binds to A with a Kd constant of less than a certain value”, or “a monoclonal antibody that binds to a human EGFR, which competively binds to antibody A but does not competively bind to antibody B”;
In the field of life science, product claims should generally avoid using any feature of function or effect to define the invention. Only if a certain technical feature cannot be defined with a feature of structure, or the technical feature is less properly defined with a feature of structure than with a feature of function or effect, and said function or effect can be directly and affirmatively verified by experiments or operations as stated in the description or by conventional means in the art, it is possible to allow the invention defined with a feature of function or effect. That is to say, a product claim usually needs to be defined by a structural feature of the product. In practice, for an antibody-related claim, the examiners usually require us to define the sequence structure of the antibody. For an antibody that is defined by function, the examiners usually takes stricter examination standard under the current practice.
II. Issues which often occur in the examination practice of antibody-related patent applications
In practice, the issues raised by examiners for antibody-related patent applications mainly involve novelty, inventive step, support issue, enablement issue (insufficient disclosure), unity, clarity issue, and new matter issue. These hot issues are discussed below by using recent case studies to help you better understand the current patent practice relating to antibody-related patent applications in China.
1. Novelty issues
For novelty, in brief, it means that the invention submitted does not belong to the prior art (no discussion is made on conflicting applications here). In antibody-related applications, a lack of novelty is relatively rare. As long as we may demonstrate that the antibody sequence is a new sequence or is a monoclonal antibody against a new antigen, it is generally easy to overcome the novelty issue.
In practice, for a claim of a pharmaceutical composition or pharmaceutical use, we shall pay more attentions to the limitation effect of the technical features associated with the administration of a drug, such as administration dose and subject, on the pharmaceutical composition or pharmaceutical use when determining the novelty. Specifically, in the field of life science, if the difference between the claimed pharmaceutical use claim and the technical solution disclosed by the prior art only lies in the administration dose and/or administration regimen, the examiners usually hold that the administration dose and/or administration regimen are only closely related to the physician’s choice of the therapeutic scheme, but are not necessarily related to the drug and its preparation themselves, and thus concludes that the distinguishing technical features merely present in the course of administration do not enable the swiss-type use claims to possess novelty.
Case 1：Invalidation Decision No. 19128
This case relates to the use of huMAb4D5-8 antibody in the manufacture of a product for the treatment of a human patient susceptible to or diagnosed with breast cancer characterized by overexpression of ErbB2 receptor. Its difference from the prior art evidence 1 lies in that: the administration dose and regimen defined in Claim 1 are that the initial dose of 8 mg/kg and the medicament for subsequent use is administered at a dose of 6 mg/kg at 3-week intervals after a target trough serum concentration 10-20 μg/ml is obtained by the medicament for initial use. However, the Collegiate Panel of the Patent Reexamination Board held that the definitions of the administration dose and timing are a physician’s selections in the process of administration of medicament during treatment, and would not have a substantial impact on the raw materials of the medicament manufactured, the manufacturing process, indications, and the like. The manufacturing process and indications of the medicament are not affected. Hence, the definitions of the administration dose and timing cannot constitute a substantial difference for the pharmaceutical preparation use of the medicament. Therefore, the technical solution of Claim 1 is not novel over the evidence 1. Likewise, regarding Claim 11 (which is directed to an article of manufacture, and a package insert or label thereof contains explanatory notes of the dose and timing of administration), the panel thinks that the explanatory notes of the dose and timing of administration do not belong to features of the structure and/or constitution of the drug package article itself and cannot bring any substantial changes to the drug package article of the present patent. Namely, said difference cannot make the technical solution of Claim 11 novel over the evidence 1.
The patentee did not agree with the opinions of the Reexamination Board and of the first-instance court, and appealed to the Beijing Higher People's Court, whereas the Beijing Higher People's Court upheld the previous decision of the Reexamination Board. Thereafter the patentee applied to the Supreme People's Court for retrial. The Supreme People's Court determined in the retrial judgment that the dose and regimen of administration are related to a physician’s choice of the therapeutic scheme and are only reflected in drug administration, which has no limitation to the manufacturing process of a medicament and thus cannot distinguish the use claimed in Claim 1 from the known use in the evidence 1, and therefore the court held that Claim 1 is not novel. Likewise, the product Claim 11 is not novel, either.
Case 2：Reexamination Decision No. 107121
In practice, for an antibody claim defined by binding property, the claim is novel if the binding property implies that the claimed antibody has a structure and/or constitution distinct from a product disclosed by the prior art.
In this case, Claim 1 is directed to an antibody, which binds to an epitope consisting of a peptide having the amino acid sequence shown in SEQ ID NOs: 1 to 16 and does not cross-react with the active, fully processed neurotoxin polypeptide.
The examiner believed that the sequence of amino acids 439-449 of SEQ ID NO: 1 of D1 is exactly the same as SEQ ID NO: 1 of the present invention; an antibody that binds to a polypeptide having at least five amino acids and not more than 60 amino acids from SEQ ID NO: 1 in D1 includes an antibody that binds to an epitope consisting of a peptide having the amino acid sequence shown in SEQ ID NO: 1; an antibody includes a polyclonal antibody; since a polyclonal antibody is a mixture, it is not possible to distinguish an antibody disclosed in D1 from an antibody, which binds to an epitope consisting of a peptide having the amino acid sequence shown in SEQ ID NOs: 1 to 16 and does not cross-react with the active, fully processed neurotoxin polypeptide as stated in Claim 1 in terms of structure and constitution. Hence, the examiner concluded that they have the same structure and/or constitution rendering Claim 1 not novel, and accordingly made a Final Rejection to the present application.
The applicant disagreed with the examiner’s opinions, and filed a Request for Reexamination. The Collegiate Panel believed that: although the antibody generalized by D1 includes an antibody that binds to an epitope consisting of a peptide having the amino acid sequence shown in SEQ ID NO: 1, the polyclonal antibody that is not subjected to corresponding specific purification and binds to an epitope consisting of a peptide having the amino acid sequence shown in SEQ ID NO: 1 in D1, inevitably cross-reacts with the active, fully processed neurotoxin polypeptide. The antibody defined by Claim 1 of the present invention apprently excludes the possibility of cross-reacting with the active, fully processed neurotoxin polypeptide. Consequently, there is a difference in structure and/or constitution between the antibody of Claim 1 and the antibody of D1. Therefore, Claim 1 is novel over D1.
2. Inventiveness issues
Inventive steps occupy an very important position in the substantive examination of patent prosecution. In the evaluation of inventive steps, it is usually necessary to determine whether the claimed invention is obvious over the prior art. As prescribed in the Guidelines for Patent Examination, non-obviousness usually needs to be evaluated according to the following three steps: determining the closest prior art, determining the distinguishing technical feature of the invention and the technical problem actually solved by the invention, and judging whether the claimed invention is obvious for those skilled in the art.
Case 3: Reexamination Decision No. 116243
Claim 1 of this case is directed to a method for decreasing the immunogenicity of antibody variable domains comprising a variable light chain and/or a variable heavy chain comprising the step of substituting one or more amino acid residues of the variable light chain and/or the variable heavy chain, said residue being present at the interface between the variable chain and the constant chain of a corresponding full-length antibody. In this case, the examiner believed that D1 alters the immune effect of an antibody by mutating a variable region, whereas the present application alters the immune effect of antibody variable domains by mutating antibody variable domains. D1 has provided the technical teaching of altering the immune effect of antibody variable domains by mutating antibody variable domains, which also has the similar alteration strategies, technical means and the like. Therefore, the examiner determined that Claim 1 of the present application is not inventive, and thus made a Final Rejection to the present application.
Although the applicant incorporated “wherein the antibody variable domain is an scFv, an Fv fragment or a single domain antibody” into the original Claim 1, the Patent Reexamination Board believed in the Notification of Reexamination that the technical problem actually solved by Claim 1 is to seek specific regions of substitution and mutation of amino acids associated with decreasing the immunogenicity of antibody variable domains. Based on the general demand for decrease of the immunogenicity of an antibody or antibody fragment in the art, when faced with the technical problem of how to decrease the immunogenicity of an scFv, an Fv fragment or a single domain antibody, on the basis of the common knowledge of the art in combination with the teachings of D1 and D2, those skilled in the art can choose to substitute one or more amino acids at the interface and in the region exposed to the molecular surface of these antibody variable domains, so as to remove or alter the immunogenic epitopes. Therefore, the examiner concluded that Claim 1 is not inventive.
Regarding the opinions of the Patent Reexamination Board, the applicant forms new Claim 1 by specifically defining the site of the substituted amino acid residue on the variable light chain and variable heavy chain as well as the specific type of the amino acid residue after substitution. The Patent Reexamination Board believed that when the difference between the method for decreasing antibody immunogenicity claimed by Claim 1 and the closest prior art lies in selecting a particular amino acid mutation site and its combination type, since the type of the combination of the particular site and amino acids is related closely to the spatial structure and function of the antibody, if the particular selection can produce beneficial technical effect, the method has prominent substantive features and represents a notable progress. The Patent Reexamination Board held that the ameded Claim 1 is inventive and finally withdrew the previous Decision of Final Rejection.
Regarding the inventive step of a monoclonal antibody, there are relevant provisions in the Guidelines for Patent Examination: if an antigen is a known antigen and it is clearly known that the antigen has immunogenicity (for example, it can be concluded that an antigen has immunogenicity if a polyclonal antibody of the antigen is known or the antigen is a polypeptide with a large molecular weight), an invention of monoclonal antibody of said antigen does not comprise inventive steps. However, if the invention is further defined by other features, and hence has unexpected technical effects, the invention of that monoclonal antibody is inventive.
Case 4: Reexamination Decision No. 92402
This case is directed to an isolated antibody or an antigen-binding portion thereof, comprising: a heavy variable region comprising SEQ ID NO: 1 and a light variable region comprising SEQ ID NO: 2.
The examiner believed in the Decision of Final Rejection that the difference between the present invention and the reference document lies in that the specific amino acid sequences of light and heavy chain variable regions of a monoclonal antibody for the same epitope are not identical. Those skilled in the art are fully motivated to obtain another monoclonal antibody capable of binding to the neutralization epitope using the linear epitope, and to determine the amino acid sequence of the light and heavy chain variable regions thereof, which process is a conventional technical means of the art; besides, the obtained monoclonal antibody that is different from the antibody disclosed by D1 does not show unexpected technical effect as compared to the monoclonal antibody of D1, either. Therefore, the technical solution above is not inventive.
The applicant disagreed with the examiner’s opinions, and filed a Request for Reexamination.
The Patent Reexamination Board believed that as compared to the antibody disclosed by D1, although the antibody of Claim 1 is directed against the same epitope, the amino acid sequences of the light and heavy chain variable regions constituting the monoclonal antibody, particularly the amino acid sequence of the CDR region, is changed such that the ability of the human antibodies 83-128 of the present invention to bind to an antigen is somewhat different from the antibody AP33 disclosed by D1. According to the disclosure of the description of the present application, the human antibodies 83-128 of the present invention are less sensitive to the mutation of N415 than the antibody AP33 of D1, and thus have higher resistance to the HCV mutation. In this sense, it is believed that the antibodies 83-128 of the present invention produce unexpected technical effect. Therefore, Claim 1 possesses inventive step as required by Article 22, Paragraph 3 of the Chinese Patent Law.
3. Support issues
The technical solution for which protection is sought in each of the claims shall be a solution that those skilled in the art can reach directly or by generalization from the contents sufficiently disclosed in the description, and shall not go beyond the scope of the contents disclosed in the description. In the field of antibodies, the examiner usually implements more stringent standards for support issue in practice. A common support issue is that the examiner believes that the claim does not define the sequence structure of an antibody, or even if defined, it also encompasses a broader scope than the antibodies verified by experiment in the invention, and therefore the examiner usually requires that the claim shall be limited to those antibodies having experimental effect basis in the Examples. In practice, the examiner generally believes that for an antibody claim it is usually necessary to define six CDR sequences, and in some cases it is also necessary to define an FR sequence.
Case 5: Reexamination Decision No. 63420
The examiner believed in the Decision of Final Rejection that an FR region is also an essential structural-functional unit that participates in the antibody folding formation; it is not possible to predict that the technical solution of an antibody or a preparation method thereof which merely defines the CDR region but not defines the FR region can also achieve the desired effect; hence, the examiner believed that the claim not defining the FR region is not supported by the description.
The applicant disagreed with the examiner’s opinions, and filed a Request for Reexamination. The Patent Reexamination Board believed that Claim 1 is directed to an isolated specific binding member for human IL-13, comprising an antibody antigen-binding site which is composed of a human antibody VH domain and a human antibody VL domain, and specifically defines the CDR sequences of the VH and VL domains. The inventive purpose of the present application is to provide an antigen antibody-binding region which has a modified variable region and is still able to bind to IL-13. Meanwhile, those skilled in the art can predict that six CDR regions of an antibody basically determine the antigen-binding specificity of the antibody; the description has recited the valence values of dozens of antigen antibody-binding regions constructed by the CDR region defined by the claim, and the results show that they have effective binding activities. Hence, those skilled in the art can reasonably predict that six CDR regions of the antibody basically determine the antigen-binding specificity of the antibody, and therefore the sequence which does not further specifically define other parts of the antibody such as the FR region is reasonable. Therefore, the grounds of rejection that the failure to define the FR region results in that the claim is not supported by the description in the Decision of Final Rejectionare are not tenable.
Case 6: Reexamination Decision No. 80566
In this case, the examiner believed that an antibody claimed must simultaneously define the complete amino acid sequences (amino acid sequences comprising CDRs and FRs) of the heavy chain and light chain variable regions of the antibody in order to ensure that said antibody is able to bind to a particular antigen. Hence, Claim 1 generalizes an overly broad scope and is not supported by the description, and therefore the present application is finally rejected.
The applicant disagreed with the examiner’s opinions, and filed a Request for Reexamination. The Patent Reexamination Board believed that it is well known in the art that there are several interation action sites between an FR region and a CDR region, which play a conformation-stabilizing role in the binding of an antibody to an antigen. If these sites of action disappear, the binding force of the antibody to the antigen can be reduced or even lost. By combining the technical problem to be solved by the present application and the overall effect of the antibody variable region shown in the Effect Examples, including the due role that FR plays therein, under the circumstances that the description does not further provide experimental data that an antibody or a fragment thereof still binds to FZD10 after the FR region is changed, an antibody claimed must simultaneously define the complete amino acid sequences (amino acid sequences comprising CDRs and FRs) of the heavy chain and light chain variable regions of the antibody in order to ensure that said antibody is able to bind to a particular antigen.
The applicant finally amended the claim to define the amino acid sequences of the heave chain and light chain variable regions. Based on the amended text, the Patent Reexamination Board withdrew the Decision of Final Rejection.
The support issue is a common issue in the procedure of patent application examination in the field of life science. As stated above, in the field of antibodies, the examiner usually implements more stringent standards for support issue in practice. If possible, it is necessary to list as many antibody Examples as possible in the description and to correspondingly verify the function and effect thereof when drafting a new application, resulting in that those skilled in the art, based on the disclosure of the description, can believe that the scope generalized by the claim is reasonable, such that it is easier to persuade the examiner to accept the generalized claim.
4. Issues of insufficient disclosure
As for a chemical product invention, the use and/or its technical effect of the product shall be completely disclosed. If the description sets forth a concrete technical solution but without experimental evidence, while the solution can only be established upon confirmation by experimental result, the technical solution belongs to the circumstances in which the technical solution is regarded as unable to be carried out due to lack of technical means to solve the technical problem.
Case 7: Reexamination Decision No. 52636
This case relates to a novel Neutrokine α protein which is a member of the TNF protein family, with the applicant being Human Genome Sciences, Inc. In the examination procedure the examiner believed that the description does not sufficiently disclose the function and medical use of the claimed antibody and made the Decision of Final Rejection to the present application.
In the Decision of Final Rejection, the examiner believed that the description of the present application merely provides the amino acid sequence of the Neutrokine α, but does not provide qualitative or quantitative experimental evidence to demonstrate the function and medical use of the claimed polypeptide; the description merely theoretically infers that the polypeptide has the same function as TNF and relevant cytokines based only on the homology of the amino acid sequence. However, as a research means, the results of the homology deduction merely provide guidance on the subsequent research direction, and the real function of the target sequence must be confirmed by biological experiment. Therefore, the description of the present application does not sufficiently disclose the function and medical use of the claimed polypeptide, and does not comply with the provision of Article 26, Paragraph 3 of the Chinese Patent Law.
Human Genome Sciences, Inc. was not satisfied with the Decision of Final Rjection made by the examiner and filed a Request for Reexamination. The Patent Reexamination Board believed that the description of the present application predicts the particular function of the nucleic acid and polypeptide by means of similar domain constitution and sequence homology comparison; under the circumstances that the description of the present application has no specific experimental data to demonstrate the aforesaid result of prediction (conjecture), those skilled in the art cannot confirm that the polypeptide of the present invention has the similar biological function and activity to TNF and relevant cytokines. Secondly, in the absence of any experimental evidence, those skilled in the art can neither prove that the nucleic acid and polypeptide of the present invention are indeed associated with a certain disease, nor confirm that the nucleic acid and polypeptide of the present invention have the use of diagnosing and treating diseases. Therefore, the Patent Reexamination Board upheld the Decision of Final Rejection.
Regarding inventions relating to a gene, a vector, a recombinant vector, a transformant, a polypeptide or a protein, a fused cell, a monoclonal antibody and the like, the description shall not only explicitly disclose the identification and preparation of the product, but also sufficiently provide experimental evidence for a person skilled in the art to be convinced that the product has a special function. That is to say, the description shall disclose the technical means and conditions which are needed to obtain the function, use and/or effect, as well as the qualitative or quantitative data of experimental tests which are sufficient to prove that, for example, an antibody enables the use and/or effect to be carried out.
5. Unity issues
A patent application for invention shall be limited to one invention. Two or more inventions or utility models belonging to a single general inventive concept may be filed as one application. That is to say, where there are several inventions or utility models in one application, the application is acceptable only if all the inventions or utility models are so linked as to form a single general inventive concept.
Case 8: Reexamination Decision No. 11038
This case relates to an anti-VEGF antibody having a mutation(s) in CDR regions. The examiner believed in the Decision of Final Rejection that: Claims 1-45 comprise a large number of parallel technical solutions, and the common technical feature among these solutions is: an anti-VEGF antibody with a high affinity produced by a mutation in the CDR regions. However, D1 has disclosed said feature.
The applicant amended the claims and argued that the antibodies in the amended claims all possess reduced immunogenicity, which feature is not disclosed by D1. Hence, the claims have a special technical feature, and possess unity.
The Collegiate Panel believed that: although the six mutants specifically defined by the claims involve different structures, they all have reduced immunogenicity, and all belong to VEGF antibodies having reduced immunogenicity compared to the antibody having the six specific CDR regions; that is, all of the aforesaid antibodies possess the same performance. However, D1 does not disclose that a mutation in CDR regions may reduce the immunogenicity of an antibody, nor does it recite a relationship between the mutations in CDR regions and the reduction in immunogenicity. Hence, under the circumstances that there are no evidences that the prior art has disclosed the aforesaid common technical feature among the multiple technical solutions claimed by Claim 1, it it not possible to conclude that the aforesaid common technical feature does not belong to a special technical feature among the multiple technical solutions, and thus cannot further conclude that the parallel technical solutions of Claim 1 do not belong to a single general inventive concept. Therefore, the Patent Reexamination Board believed that the amended claims possess unity.
To determine whether two or more inventions claimed in a patent application meet the requirement of unity depends on whether these claims contain one or more of the common or corresponding special technical features which make the claimed inventions technically interrelated. The unity issue is related closely to the novelty and inventive step of an invention. In practice, it is necessary to persuade the examiner that the common feature among the various invenitons is a technical feature that makes contributions to the prior art.
6. New matter issues
If the amended contents are neither recited in the initial description and claims, nor can be determined directly and unambiguously according to the contents of the initial description and claims, and the drawings of the description, such amendment involves new matter issue and does not comply with the provision of Article 33 of the Chinese Patent Law.
Case 9: Reexamination Decision No. 52636
This case relates to a pharmaceutical composition comprising a CD19 antibody. The applicant further defined the sequence information of light chain CDRs 1-3 in the claims during examination. The examiner believed that the aforesaid amendment is not recited in the initial application documents; according to the amino acid sequence of the light chain Vk of the antibody as recited in the initial application documents, a person skilled in the art cannot determine the starting points of CDRs or highlight the CDR regions or other similar information. Therefore, said amendment involves new matter issue.
The applicant argued that the determination of the CDR sequence of the VH or VL region of the antibody is just a conventional experiment at the priority date of the present application, and thus filed a Request for Reexamination.
The Patent Reexamination Board believed that the initial description and claims of the present application do not clearly recite the specific sequence information of CDRs 1-3 of the light chain of the antibody HB12a or HB12b, e.g. the specific sequences thereof or their positions in the whole sequence. A person skilled in the art cannot determine or derive the sequences of CDRs or the amendment information such as highlighting the CDR regions, based on the disclosure of the description, claims and drawings. Hence, a person skilled in the art cannot directly and unambiguously determine said amendment according to the initial application documents. Finally, the Patent Reexamination Board upheld the Decision of Final Rejection.
In practice, the examiner adopts a strict standard for the new matter issue. If, after the addition, change and/or deletion of part of the contents of the application, the information as seen by a person skilled in the art is different from those described in the initial application and such information cannot be directly or unambiguously derived from those described in the initial application, such amendment is generally not allowable.
When drafting a new application, we should carry out a sufficient search and reasonably design the scope of the claims anduse appropriate terms, and on the other hand, we shall provide a basis for future possible amendments as far as possible in the initial texts.
7. Whether or not a claim has a clear scope of protection.
The scope of protection of a claim shall be construed according to the meaning of the words as used in the claim. Generally, in practice, whether the scope of protection of a claim in the field of antibodies is clear mainly involves: whether a term in the claim is clear; whether the utilization of parenthesis in the claim is clear (for example, the contents inside and outside the parenthesis limit different scopes of protection); the utilization of “about” in front of a value; the definition of low, medium, and high stringent hybridization conditions in the definition of a sequence; “a sequence basically consists of …”; and the like. The words used in a claim shall be understood as having the meaning which they normally have in the relevant art. If a person skilled in the art can clearly understand the meaning of the words used in the claim and determine the scope of protection of the claim, according to the common technical knowledge that he is aware of, the claim shall be regarded as explicitly expressing the scope sought for patent protection. A case is provided below for further explanation.
Case 10: Invalidation Decision No.: 23523
Claim 1 of this case relates to a polypeptide comprising an antigenic portion of a M.tuberculosis antigen, wherein said antigen comprises an amino acid sequence encoded by SEQ ID NO: 46.
The petitioner for invalidation argued that “an antigenic portion of … antigen” in the claim is not explicitly expressed. An “antigenic portion” should be understood as a portion of an antigen that is capable of eliciting an immune response or reacting with sera obtained froman infected individual. However, in different subjects, including human beings and other animals, cells, etc., the portion of an antigen that is capable of eliciting an immune response varies by the subject, the configuration of the antigen itself, and the like; the portion resulting from the antigen elicitation in the serum obtained from an individual infected with M.tuberculosisalso varies by the subject, the antigen itself and the like. Hence, a person skilled in the art cannot determine which portion(s)of the antigen on earth the antigenic portion of the antigen of Claim 1 is, and cannot explicitly determine the scope of the polypeptide of Claim 1.
The patentee thought that “an antigenic portion” is explicitly expressed, and has a clear definition in the description, and therefore, the term is clear.
The Collegiate Panel believed that: as recited in the description of the present application: an “antigenic portion” of an antigen (which may or may not be soluble) is a portion that is capable of reacting with sera obtained from an M.tuberculosis-infected individual (i.e., generates an absorbance reading with sera from infected individuals that is at least three standard deviations above the absorbance obtained with sera from uninfected individuals, in a representative ELISA assay described herein). As such, the description has provided a clear definition to the antigenic portion. A person skilled in the art can understand the meaning of said definition, and thus determine the scope of the antigenic portion. Therefore, the scope of protection of Claim 1 is clear.
Whether the scope of protection of a claim is clear is very important to the determination of the scope of protection of the claim. If some terms have a particular meaning, it is necessary to provide a clear definition in the description when drafting the description, in order to accurately define the scope of protection of the claim.
III. Summary
In an antibody-related patent application, regarding the novelty issue, it shall be noted that not all of the distinguishing technical features may be regarded as having limiting effect on the claim. As for an invention of a product such as an antibody defined by a function, effect or use feature, generally it is necessary to explain that the definition of said function, effect or use feature enables the product as claimed to have a structure and/or constitution distinct from that of the product disclosed in the prior art.
Regarding both the inventiveness issue and the insufficient disclosure issue(enablement issue), it is necessary to recite the technical effect to some extent in the initial description, and it is even necessary to recite qualitative or quantitative data of experimental tests which are sufficient to prove that an antibody enables the use and/or effect to be carried out. Therefore, we need to conduct careful consideration when drafting an invention, so as to leave sufficient space and basis for possible argument in the future.
Regarding unity issue, if it is difficult to persuade the examiner by using the structural feature of the antibody itself, e.g. the mutated antibody mentioned in the aforesaid case, we may consisder arguing based on the combination of a structural feature and a functional feature, which may be more effective.
Regarding the new matter issue, the examiners take more stringent standards in practice. We need to argue according to the facts and information owned by the initial application, which also reminds us to carry out a sufficient search and reasonably design the scope of the claims and use appropriate terms, and on the other hand, to provide a sufficient basis for future possible amendments as far as possible in the initial texts when drafting a new application.
Regarding the non-clarity issue, if some term has a particular meaning, it is necessary to provide a clear definition in the description when drafting the description, in order to accurately define the scope of protection of the claim.
China is changing from a great nation of intellectual property to a powerful nation of intellectual property, with continually updated laws and regulations of intellectual property as well as gradually strengthened patent enforcement efforts. In the face of such a huge biomedical market in China, it is of vital significance for biomedical enterprises to understand the above-mentioned examination and judicial practice concerning a patent application in the field of antibodies and carry out a reasonable patent portfolio, as well as to obtain a patent right with stable and reasonable scope of protection.