Method for inducing an immune response

Description

1 / 79 METHOD FOR INDUCING AN IMMUNE RESPONSE FIELD TECHNIQUE

[0001] The present invention relates to methods for inducing an immune response in a subject, the method comprising orally administering to the subject an immunogenic composition comprising a non-replicating viral antigen. In one example, an immunogenic composition is administered orally to a pig, wherein the immunogenic composition comprises a recombinant viral capsid protein capable of forming a virus-like particle. This allows for the simple induction of an immune response in pigs, simultaneously reducing the propensity for adverse reactions, eliminating the risk of injection site reactions, avoiding pain and causing less stress to the animals. BACKGROUND OF THE INVENTION

[0002] Viral infection continues to be a major health problem in animals, with adverse economic consequences. For example, there are several viral pathogens that cause disease in economically important farm animals, such as pigs. Viruses that infect pigs include, for example, porcine circovirus type 2 and porcine parvovirus.

[0003] Porcine circovirus type 2 (PCV2) is a small (17-22 nm in diameter), icosahedral, non-enveloped DNA virus containing a single-stranded circular genome. PCV2 shares approximately 80% sequence identity with porcine circovirus type 1 (PCV1). However, in contrast to PCV1, which is generally non-virulent, pigs infected with PCV2 exhibit a syndrome Petition 870250088147, dated 09 / 29 / 2025, pp. 222 / 315 2 / 79 commonly called Post-weaning Multisystemic Wasting Syndrome (PMWS). PMWS is clinically characterized by wasting, pale skin, lack of vigor, respiratory distress, diarrhea, jaundice, and yellowing. In some affected pigs, a combination of all symptoms will be apparent, while other pigs will have only one or two of these symptoms. During necropsy, microscopic and macroscopic lesions also appear in various tissues and organs, with lymphoid organs being the most common site for lesions. A strong correlation has been observed between the amount of PCV2 nucleic acid or antigen and the severity of microscopic lymphoid lesions. Mortality rates for pigs infected with PCV2 can reach 80%. In addition to PMWS, PCV2 has been associated with several other infections, including pseudorabies, porcine reproductive and respiratory syndrome (PRRS), Glasser's disease, streptococcal meningitis, salmonellosis, post-weaning colibacillosis, dietary hepatosis, and suppurative bronchopneumonia.

[0004] Several vaccines are available to reduce the impact of PCV2 infections in swine. U.S. Patent No. 6,703,023 (US 6,703,023 B1) provides a DNA-based vaccine for the prophylaxis of swine against PMWS, in which this and the following publications referenced herein are incorporated by reference in their entirety. In WO2003049703, the production of a live chimeric vaccine is described, comprising the non-pathogenic PCV1 virus in which, however, the ORF2 protein is replaced by the ORF2 protein of Petition 870250088147, dated 09 / 29 / 2025, pp. 223 / 315 3 / 79 Pathogenic PCV2. WO199918214 and WO199929717 provided several PCV2 strains and procedures for the preparation of an inactivated PCV2 vaccine. The preparation of subunit vaccines was also described in WO199918214 and WO199929717. An effective ORF2-based subunit vaccine was reported in WO2006072065. Other ORF2-based subunit vaccines are also described in WO200728823 or WO2015051099.

[0005] Porcine parvovirus (PPV) is a self-replicating virus of the Parvovirinae subfamily of the Protoparvovirus genus, within the Parvoviridae family, containing a single-stranded DNA molecule of approximately 5100 nucleotides. Only the negative strand of DNA is incorporated into virions. The virus genome encodes three capsid proteins (VP1, VP2, VP3) and one non-structural protein (NS1). The parvovirus capsid is approximately 22–25 nanometers in diameter and is composed of the VP1 and VP2 subunits. These proteins are derived from alternatively spliced ​​versions of the same RNA molecule and therefore overlap in sequence. Furthermore, porcine parvovirus exhibits a high level of sequence similarity to feline panleukopenia virus and canine parvoviruses.

[0006] PPV infection is a common cause of reproductive failure in breeding pigs worldwide. Serological studies show that porcine parvovirus is widespread in all pig-producing regions of the world, with up to 80% of animals showing seroconversion.

[0007] The vaccines currently available against PPV are produced, on the one hand, by cultivating the native virus in primary cells of porcine origin or in lines Petition 870250088147, dated 09 / 29 / 2025, pp. 224 / 315 4 / 79 cells are established, and after that, the infectious virus is isolated and inactivated with chemical agents to obtain a whole-cell killed virus vaccine. On the other hand, an effective subunit vaccine based on VP2 and its production were reported in WO2018083154 or WO2018083156.

[0008] Vaccinating swine with conventional viral vaccines, such as PCV2 and PPV, which is usually done by injection, can result in injection site reactions, increases the likelihood of adverse reactions, and is often a risk factor for adverse reactions. Furthermore, this vaccination is associated with pain and stress for the animals.

[0009] Thus, routes of administration for non-replicating viral antigens are desired that can be easily practiced and that elicit an immune response against the virus in swine, while resulting in less propensity for adverse reactions, not presenting the risk of injection site reactions, avoiding pain and causing less stress to the animals. DESCRIPTION OF THE INVENTION

[0010] The solution to the above technical problems is achieved by the description and embodiments characterized in the claims.

[0011] Thus, the invention in its different aspects is implemented in accordance with the claims.

[0012] The invention is based on the surprising discovery that oral administration of an immunogenic composition comprising a recombinant ORF2 protein from Petition 870250088147, dated 09 / 29 / 2025, pages 225 / 315 5 / 79 PCV2 in pigs resulted in their immunization against PCV2.

[0013] In a first aspect, the invention thus relates to a method for - to induce an immune response in a subject, or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method comprising orally administering to the subject an immunogenic composition comprising a non-replicating viral antigen, and wherein said method is also referred to as “the method of the present invention” hereafter.

[0014] In one aspect, the method of the present invention is a method for inducing an immune response in a subject, the method comprising orally administering to the subject an immunogenic composition comprising a non-replicating viral antigen.

[0015] In another aspect, the method of the present invention is a method for reducing one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method comprising the oral administration to the subject of an immunogenic composition comprising a non-replicating viral antigen.

[0016] In a further preferred aspect, the method of the present invention is preferably a method for - to induce an immune response in a subject and - to reduce one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject, Petition 870250088147, dated 09 / 29 / 2025, pp. 226 / 315 6 / 79 The method comprises orally administering to the subject an immunogenic composition comprising non-replicating viral antigen. Said immunogenic composition, which is also referred to as the "immunogenic composition according to the present invention" hereafter, is preferably free of replicating viral antigen.

[0017] The aforementioned non-replicating viral antigen, which is also referred to as the "non-replicating viral antigen according to the present invention" hereafter, preferably comprises or is a recombinant protein.

[0018] The said recombinant protein, which is also referred to as the recombinant protein according to the present invention hereafter, is preferably capable of forming a virus-like particle.

[0019] As used in this document, the term “virus-like particle” refers to a structure similar to a viral particle, but which is non-pathogenic, non-replicative and non-infectious, since it lacks all or part of the viral genome.

[0020] Preferably, the recombinant protein according to the present invention is a protein expressed by recombinant baculovirus.

[0021] The term “recombinant”, as used in this document, is understood, in particular, as equivalent to “recombinantly expressed”. Thus, for example, “recombinant viral protein” is equivalent to “recombinantly expressed viral protein”.

[0022] The non-replicating viral antigen according to the present invention is preferably a viral protein. Petition 870250088147, dated 09 / 29 / 2025, pp. 227 / 315 7 / 79 recombinant, in particular a viral protein expressed by recombinant baculovirus.

[0023] The term “recombinant viral protein” or “recombinantly expressed viral protein,” respectively, as used in this document, refers in particular to a viral protein that is produced by recombinant DNA techniques, wherein generally the DNA encoding the expressed protein is inserted into a suitable expression vector which, in turn, is used to transform a viral protein and, in the case of a viral vector, to infect a host cell to produce the heterologous protein. Thus, the term “recombinant viral protein” or “recombinantly expressed viral protein,” respectively, as used in this document, refers particularly to a protein molecule that is expressed from a recombinant DNA molecule. “Recombinant DNA molecule,” as used herein, refers to a DNA molecule that is composed of DNA segments joined together by means of molecular biology techniques.Suitable systems for the production of recombinant proteins include, among others, insect cells (e.g., baculovirus), prokaryotic systems (e.g., Escherichia coli), fungi (e.g., Myceliophthora thermophile, Aspergillus oryzae, Ustilago maydis), yeasts (e.g., Saccharomyces cerevisiae, Pichia pastoris), mammalian cells (e.g., Chinese hamster ovary, HEK293), plants (e.g., safflower), algae, bird cells, amphibian cells, fish cells, and cell-free systems (e.g., rabbit reticulocyte lysate). Petition 870250088147, dated 09 / 29 / 2025, pp. 228 / 315 8 / 79

[0024] According to a particularly preferred aspect, the immunogenic composition according to the present invention is adjuvant-free. According to a particularly preferred aspect, the immunogenic composition according to the present invention consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use.

[0025] According to a still more preferred aspect, the immunogenic composition according to the present invention consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use; and at least one immunogenic substance other than said viral antigen.

[0026] According to another aspect, the immunogenic composition according to the present invention consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use; and at least one adjuvant.

[0027] According to another aspect, the immunogenic composition according to the present invention consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use; and at least one adjuvant; and Petition 870250088147, dated 09 / 29 / 2025, pp. 229 / 315 9 / 79 at least one immunogenic substance other than the aforementioned viral antigen.

[0028] Preferably, the immunogenic composition according to the present invention additionally contains a gel composition, which is also referred to as "the gel composition according to the present invention" hereafter.

[0029] The immune response, as mentioned in this document, is preferably a protective immune response.

[0030] Preferably, the immune response mentioned in this document is an immune response against a virus, wherein the virus in question is a virus of the species that has a genome that codes - the non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen.

[0031] Preferably, the virus in question is PCV2.

[0032] Preferably, the aforementioned immune response is an immune response against PCV2.

[0033] Thus, the method according to the present invention is preferably a method for - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject, the method comprising administering orally to the subject an immunogenic composition comprising non-replicating PCV2 antigen. Petition 870250088147, dated 09 / 29 / 2025, pages 230 / 315 10 / 79

[0034] As used in this document, the term “viral antigen” means a substance derived from a virus or a component thereof or both, the substance being capable of inducing an immune response. For example, the term “PCV2 antigen” means, in particular, a substance derived from a PCV2 or a component thereof or both, the substance being capable of inducing an immune response.

[0035] The term “non-replicating viral antigen” refers, in particular, to molecules derived from a virus, such as proteins, carbohydrates, lipids, or nucleic acids, or complex combinations thereof, more or less pure. When prepared from a virus, the non-replicating antigen may refer to an intact but dead (i.e., non-replicating) virus, or it may be a part of it, such as an extract, fraction, homogenate, or sonicate. Furthermore, a non-replicating viral antigen may be a nucleic acid-based or recombinant product, such as an expression vector or an expressed protein, or the product of an in vitro expression system. All of these are well known in the art.

[0036] Preferably, the non-replicative viral antigen according to the present invention is a recombinant viral protein. The term “viral protein” encompasses any protein derived from a virus. Specific examples include a viral capsid protein, a viral coat protein, a viral envelope protein, and a viral core protein. Petition 870250088147, dated 09 / 29 / 2025, pages 231 / 315 11 / 79

[0037] As used in this document, the term “antigenic determinant” is understood, in particular, as referring to that portion of an antigen that is specifically recognized by B or T lymphocytes. B lymphocytes respond to foreign antigenic determinants through the production of antibodies, while T lymphocytes are the mediators of cellular immunity. Thus, antigenic determinants or epitopes are the parts of an antigen that are recognized by antibodies or, in the context of a Major Histocompatibility Complex (MHC), by T cell receptors. An antigenic determinant contains one or more epitopes.

[0038] Preferably, the antigenic determinant mentioned in this document is a protein capable of forming a virus-like particle.

[0039] Preferably, the non-replicating viral antigen according to the present invention is a virus-like particle.

[0040] The aforementioned virus-like particle, which will hereinafter also be referred to as "the virus-like particle according to the present invention", preferably comprises a recombinant protein (also referred to, as mentioned above, as "the recombinant protein according to the present invention").

[0041] Preferably, the recombinant protein according to the present invention is a recombinant capsid protein of the virus. Petition 870250088147, dated 09 / 29 / 2025, pages 232 / 315 12 / 79

[0042] More preferably, the recombinant protein according to the present invention is a recombinant capsid protein of circovirus.

[0043] In another aspect, the non-replicating viral antigen according to the present invention is a recombinant capsid protein from porcine circovirus (PCV).

[0044] In particular, the non-replicating viral antigen according to the present invention is a recombinant ORF2 protein of porcine circovirus type 2 (PCV2), wherein said PCV2 ORF2 protein preferably comprises or consists of an amino acid sequence with at least 90%, preferably at least 95%, more preferably at least 98%, even more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:1.

[0045] According to another preferred aspect, the non-replicating viral antigen according to the present invention is selected from the group consisting of protein Recombinant ORF2 protein of PCV2 subtype a (PCV2a), recombinant ORF2 protein of PCV2 subtype b (PCV2b), recombinant ORF2 protein of PCV2 subtype c (PCV2c), recombinant ORF2 protein of PCV2 subtype d (PCV2d), recombinant ORF2 protein of PCV2 subtype e (PCV2e), recombinant ORF2 protein of PCV2 subtype f (PCV2f), recombinant ORF2 protein of PCV2 subtype g (PCV2g) and protein Recombinant ORF2 of PCV2 subtype h (PCV2h).

[0046] The terms PCV2a, PCV2b, PCV2c, PCV2d, PCV2e, PCV2f, PCV2g, PCV2h, as used in this document, refer in particular to the classification Petition 870250088147, dated 09 / 29 / 2025, pages 233 / 315 13 / 79 established PCV2 genotype, described in: Franzo G & Segalés J. PLos One 13(12):e0208585 (2018) and Link EK et al. Virol J. 18(1):70 (2021).

[0047] In a specific aspect, the non-replicating viral antigen according to the present invention is a recombinant ORF2 protein of genotype a of PCV2 (PCV2a).

[0048] Preferably, the recombinant ORF2 protein of PCV2a mentioned in this document comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:1.

[0049] According to another specific aspect, the non-replicating viral antigen according to the present invention is a recombinant ORF2 protein of genotype d of PCV2 (PCV2d).

[0050] Preferably, the PCV2d ORF2 protein mentioned in this document comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:2.

[0051] According to another preferred aspect, the non-replicating viral antigen according to the present invention is a recombinant parvovirus capsid protein.

[0052] In one aspect, the non-replicating viral antigen according to the present invention is a capsid protein. Petition 870250088147, dated 09 / 29 / 2025, pp. 234 / 315 14 / 79 recombinant porcine parvovirus (PPV), in particular a viral protein 2 (VP2) of PPV.

[0053] Preferably, the recombinant PPV VP2 mentioned in this document comprises or consists of an amino acid sequence with at least 90%, preferably at least 95%, more preferably at least 98%, even more preferably at least 99%, or in particular, 100% sequence identity with a sequence selected from the group consisting of SEQ ID NO:3.

[0054] With respect to the term “at least 90%”, as mentioned in the context of this invention, it is understood that said term preferably refers to “at least 91%”, more preferably to “at least 92%”, even more preferably to “at least 93%” or, in particular, to “at least 94%”.

[0055] With respect to the term “at least 95%”, as mentioned in the context of this invention, it is understood that said term preferably refers to “at least 96%”, more preferably to “at least 97%”, even more preferably to “at least 98%” or, in particular, to “at least 99%”.

[0056] With regard to the term “at least 99%” mentioned in the context of this invention, it is understood that said term preferably refers to “at least 99.2%”, more preferably to “at least 99.4%”, even more preferably to “at least 99.6%” or, in particular, to “at least 99.8%”.

[0057] More specifically, the term “at least 99% sequence identity” refers to 99.1%, 99.2%, 99.3%, Petition 870250088147, dated 09 / 29 / 2025, pp. 235 / 315 15 / 79 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, or 99.9% sequence identity.

[0058] The term “having 100% sequence identity”, as used in this document, is understood to be equivalent to the term “being identical”.

[0059] As used in this document, it is understood in particular that the term “sequence identity with sequence SEQ ID NO:X” is equivalent to the term “sequence identity with sequence SEQ ID NO:X along the length of SEQ ID NO:X” or the term “sequence identity with sequence SEQ ID NO:X along the entire length of SEQ ID NO:X”, respectively. In this context, “X” is any integer selected from 1 to 3, so that “SEQ ID NO:X” represents any of the SEQ ID NOs mentioned in this document.

[0060] The term “immunogenic composition” refers to a composition comprising at least one antigen, which elicits an immune response in the host to which the immunogenic composition is administered. Such an immune response may be a cellular and / or antibody-mediated immune response to the immunogenic composition according to the invention. The host is also described as a “subject”. Preferably, any of the hosts or subjects described or mentioned in this document is an animal.

[0061] The term “animal”, as used in this document, refers in particular to a mammal, preferably a swine, more preferably a pig, and even more preferably a piglet or a sow. Petition 870250088147, dated 09 / 29 / 2025, pages 236 / 315 16 / 79

[0062] Typically, an “immune response” includes, but is not limited to, one or more of the following effects: the production or activation of antibodies, B cells, helper T cells, suppressor T cells and / or cytotoxic T cells and / or gamma-delta T cells, specifically directed to an antigen or antigens and included in the immunogenic composition according to the present invention. Preferably, the host will exhibit a protective immune response or a therapeutic response.

[0063] A “protective immune response will be demonstrated by a reduction or absence of one or more clinical signs normally presented by an infected host, a faster recovery time and / or a reduced duration of infectivity, or a reduction in the pathogen titer in the tissues, body fluids, or excretions of the infected host. For example, to assess a protective immune response against PCV2, PCV2-specific T cell immunity can be evaluated following the protocol of Koinig HC et al. Vet Res. 46:20 (2015). As is known and described in that article, multifunctional T cells, which simultaneously produce IFN-γ, interleukin-2 (IL-2), and TNFα, are strongly correlated with protection, and the appearance of IFN-γ / TNF-α co-producing T cells after PCV2 vaccination correlated with the prevention of viremia after PCV2 vaccination.Furthermore, a strong correlation is observed between the amount of PCV2 nucleic acid and the severity of histopathological lesions in PCV2 systemic disease (PCV2-SD) (Segales J. Virus Res. 164(1-2):10-19 (2012). Petition 870250088147, dated 09 / 29 / 2025, pp. 237 / 315 17 / 79

[0064] The pathogen or specific pathogen, as mentioned in this document, refers in particular to the virus from which the non-replicating viral antigen is derived. For example, the pathogen, as mentioned in this document, is a PCV2 or a PPV.

[0065] In the case where the host exhibits a protective immune response, such that resistance to new infections is increased and / or the clinical severity of the disease is reduced, the immunogenic composition is described as a vaccine.

[0066] An antigen, as described in this document, refers to, but is not limited to, components that elicit an immune response in a host to an immunogenic composition or vaccine of interest comprising such antigen or an immunologically active component thereof. In particular, the term antigen, as used in this document, refers to a protein or protein domain that, if administered to a host, can elicit an immune response in the host.

[0067] Inducing an immune response, inducing an immune response, or eliciting an immune response, respectively, generally involves administering an effective amount of the immunogenic composition according to the present invention to a subject or group of subjects who need or may benefit from the treatment / prophylaxis caused by it.

[0068] The term treatment and / or prophylaxis refers to decreasing the incidence of infection by a given pathogen in a herd or reducing the severity of an infection. Petition 870250088147, dated 09 / 29 / 2025, pp. 238 / 315 18 / 79 more clinical signs caused by or associated with infection by a particular pathogen. Thus, the term “treatment and / or prophylaxis” also refers to reducing the number of animals in a herd that are infected by a particular pathogen (= decreasing the incidence of infection by a particular pathogen) or reducing the severity of one or more clinical signs normally associated with or caused by infection by the pathogen in a group of animals that received an effective amount of the immunogenic composition described in this document, compared to a group of animals that did not receive this immunogenic composition.

[0069] The term “treatment” refers to the administration of the effective amount of the immunogenic composition once the subject or at least some animals in the herd are already infected with such pathogen and such animals already exhibit some clinical signs caused by or associated with such pathogen infection. The term “prophylaxis” refers to administration to a subject before any infection of that subject with a pathogen or, at least, when that animal or all animals in a group of animals do not exhibit one or more clinical signs caused by or associated with infection by such pathogen.

[0070] The term “effective quantity,” as used in this document, means, but is not limited to, a quantity of viral antigen, in particular of the proteins or virus-like particles of this disclosure, that induces or is capable of inducing an immune response in a subject. This effective quantity is capable of reducing the incidence of infection by a given pathogen in a Petition 870250088147, dated 09 / 29 / 2025, pp. 239 / 315 19 / 79 herd or to reduce the severity of one or more clinical signs of infection by that specific pathogen. Of Preferably, one or more clinical signs are reduced in incidence or severity by at least 10%, more preferably by at least 20%, even more preferably by at least 30%, even more preferably by at least 40%, even more preferably by at least 50%, even more preferably by at least 60%, even more preferably by at least 70%, even more preferably by at least 80%, even more preferably by at least 90%, and most preferably by at least 95% compared to subjects who are not treated but subsequently infected by the specific pathogen. Thus, the method of the present invention comprises, in particular, the oral administration of an immunogenic composition comprising an effective amount of a non-replicating viral antigen to a subject.

[0071] The term “clinical signs,” as used in this document, refers to signs of infection in a subject by the specific pathogen. The clinical signs of infection depend on the pathogen selected. Examples of such clinical signs, caused by a PCV2 infection, include, but are not limited to, emaciation or weight loss, pallor of the skin, respiratory distress, diarrhea, and occasionally jaundice.

[0072] A reduction in the incidence or severity of one or more clinical signs caused by or associated with infection. Petition 870250088147, dated 09 / 29 / 2025, pp. 240 / 315 20 / 79 for a given pathogen in a subject can be achieved through oral administration of one or more doses of the immunogenic composition according to the present invention to a subject.

[0073] In one aspect, the immunogenic composition comprises at least 10 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0074] In one aspect, the immunogenic composition comprises at least 15 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0075] In one aspect, the immunogenic composition comprises at least 30 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0076] In one aspect, the immunogenic composition comprises at least 50 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0077] In one aspect, the immunogenic composition comprises at least 100 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0078] In one aspect, the immunogenic composition comprises at least 150 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0079] In one aspect, the immunogenic composition comprises at least 200 pg of non-replicating viral antigen per dose of the immunogenic composition.

[0080] In one aspect, the immunogenic composition comprises at least 250 pg of non-replicating viral antigen per dose of the immunogenic composition. Petition 870250088147, dated 09 / 29 / 2025, pp. 241 / 315 21 / 79

[0081] In another aspect, the immunogenic composition according to the present invention comprises 10 to 800 μg of non-replicating viral antigen per dose.

[0082] In another aspect, the immunogenic composition according to the present invention comprises 15 to 800 μg of non-replicating viral antigen per dose.

[0083] In another aspect, the immunogenic composition according to the present invention comprises 30 to 800 μg of non-replicating viral antigen per dose.

[0084] In another aspect, the immunogenic composition according to the present invention comprises 50 to 800 μg of non-replicating viral antigen per dose.

[0085] In another aspect, the immunogenic composition according to the present invention comprises 100 to 800 μg of non-replicating viral antigen per dose.

[0086] In another aspect, the immunogenic composition according to the present invention comprises 150 to 800 μg of non-replicating viral antigen per dose.

[0087] In another aspect, the immunogenic composition according to the present invention comprises 200 to 800 μg of non-replicating viral antigen per dose.

[0088] In another aspect, the immunogenic composition according to the present invention comprises 250 to 800 μg of non-replicating viral antigen per dose.

[0089] In another aspect, the immunogenic composition according to the present invention comprises 300 to 800 μg of non-replicating viral antigen per dose. Petition 870250088147, dated 09 / 29 / 2025, pp. 242 / 315 22 / 79

[0090] In another aspect, the immunogenic composition according to the present invention comprises up to 800 μg of non-replicating viral antigen per dose.

[0091] In another aspect, the immunogenic composition according to the present invention comprises up to 700 μg of non-replicating viral antigen per dose.

[0092] In another aspect, the immunogenic composition according to the present invention comprises up to 600 μg of non-replicating viral antigen per dose.

[0093] In another aspect, the immunogenic composition according to the present invention comprises up to 500 μg of non-replicating viral antigen per dose.

[0094] In another aspect, the immunogenic composition according to the present invention comprises up to 400 μg of non-replicating viral antigen per dose.

[0095] In another aspect, the immunogenic composition according to the present invention comprises up to 300 μg of non-replicating viral antigen per dose.

[0096] It is understood that the wording “the immunogenic composition comprises [...] of the non-replicating viral antigen per dose of the immunogenic composition” or “the immunogenic composition comprises [...] of the non-replicating viral antigen per dose”, respectively, is, in particular, equivalent to the wording “per dose of the immunogenic composition, the antigenic composition comprises [...] of the non-replicating viral antigen” or to the wording “the immunogenic composition is formulated to allow the administration of [...] of the non-replicating viral antigen per dose”, respectively. Petition 870250088147, dated 09 / 29 / 2025, pp. 243 / 315 23 / 79

[0097] The term “per dose” or “per dose of the immunogenic composition”, respectively, as used in this document, means in particular “per dose of the immunogenic composition that must be administered to a subject” in order to achieve a desired effect, namely, to induce an immune response in the subject, and wherein the said subject is, in particular, a pig.

[0098] Preferably, particularly when administered orally, a dose of the immunogenic composition has a volume of approximately 1 mL.

[0099] The gel composition according to the present invention is, in particular, a gel composition suitable for oral and / or mucosal administration.

[0100] The term “gel composition”, as used in this document, refers to a suitable liquid, semi-solid or solid material, which includes an amount of one or more gelling agents effective for gelling the composition.

[0101] According to another aspect, an even more preferred aspect, the gel composition according to the present invention comprises water. In particular, said gel composition is a hydrogel composition.

[0102] The gel compositions according to the present invention, which can be used in the preparation of the immunogenic composition according to the present invention, are readily available. In one example, the commercially available Underline® gel concentrate (Animal Science Products, Nacogdoches, TX (USA)) is used as a gel composition included in the immunogenic composition according to the Petition 870250088147, dated 09 / 29 / 2025, pp. 244 / 315 24 / 79 present invention, but other gel compositions are also suitable.

[0103] According to another preferred aspect, the immunogenic composition according to the present invention is liquid.

[0104] In one aspect, the immunogenic composition according to the present invention is viscous.

[0105] In another aspect, the immunogenic composition according to the present invention has a viscosity of at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800 cPs (mPa-s) or higher.

[0106] In one aspect, the immunogenic composition according to the present invention has a viscosity of at least 150 mPa-s (at least 150 cP).

[0107] In another aspect, the immunogenic composition according to the present invention has a viscosity of at least 100 mPa-s (at least 100 cP).

[0108] In one aspect, the immunogenic composition according to the present invention has a viscosity of at least 50 mPa-s or at least 50 cP. In another aspect, the immunogenic composition according to the present invention has a viscosity between 50 cP (50 mPa-s) and 150 cP (150 mPa-s). In another aspect, the immunogenic composition according to the present invention has a viscosity between 50 cP (50 mPa-s) and 350 cP (350 mPa-s).

[0109] In one aspect, the immunogenic composition according to the present invention has a viscosity of at least 25 mPa-s or at least 25 cP. In another aspect, the Petition 870250088147, dated 09 / 29 / 2025, pages 245 / 315 The immunogenic composition according to the present invention has a viscosity between 25 cP (25 mPa-s) and 150 cP (150 mPa-s). In another aspect, the immunogenic composition according to the present invention has a viscosity between 25 cP (25 mPa-s) and 350 cP (350 mPa-s).

[0110] The unit of measurement for viscosity is Pa-s (pascal second) or mPa-s (millipascal second). The conventional unit of measurement is cP (centipoise). One centipoise is one millipascal-second (1 cP = 10-3 Pa-s = 1 mPa-s).

[0111] According to another aspect, the immunogenic composition according to the present invention is solid. The term solid in this context refers, in particular, to a gel with some resilience or dimensional stability, in contrast to semi-solid gels which are spreadable and do not have this dimensional stability.

[0112] The gel composition according to the present invention preferably comprises one or more flavoring agents. It is understood that, as used in this document, the expression comprises or consists of one or more flavoring agents is, in particular, encompassed by the expression comprises a flavoring agent.

[0113] The term flavoring agent, as used in this document, refers to one or more compounds or mixtures that improve palatability and / or flavor in animals, preferably in swine. In particular, one or more flavoring agents are, respectively, capable of attracting swine. Flavoring agents are well known to those skilled in the art. Flavoring agents include, but are not limited to, nutritive and non-nutritive sweeteners, Petition 870250088147, dated 09 / 29 / 2025, pp. 246 / 315 26 / 79 Flavoring additives, by-products and alternative ingredients. By way of example, suitable flavorings include, but are not limited to, sucrose, glucose, sodium saccharin, sodium cyclamate, xylitol, perilartein, sucralose, D-tryptophan, aspartame, dihydrochalcones and the like, artificial fruit flavorings (e.g., strawberry flavoring), plasma protein (e.g., spray-dried plasma protein), cheese flavorings and the like, milk powder, chocolate and chocolate by-products.

[0114] Preferably, one or more flavoring agents comprise or consist of a flavoring agent that imparts a particular flavor to the immunogenic composition according to the present invention and / or a flavoring agent that imparts a particular smell to the immunogenic composition according to the present invention. In particular, one or more flavoring agents comprise or consist of a flavoring agent capable of being tasted by a pig, such as a sweetener, and / or a flavoring agent capable of being smelled by a pig.

[0115] In particular, one or more flavoring agents comprise or consist of a sweetener and a flavoring additive capable of being smelled by pigs.

[0116] The sweetener, as mentioned in this document, is preferably selected from the group of sucrose, glucose, sodium saccharin, sodium cyclamate, Petition 870250088147, dated 09 / 29 / 2025, pp. 247 / 315 27 / 79 xylitol, perillartin, sucralose, D-tryptophan, aspartame, dihydrochalcones.

[0117] The flavoring additive, as mentioned in this document, is preferably selected from the group consisting of artificial fruit flavorings (e.g., strawberry flavoring) and cheese and similar flavorings.

[0118] More preferably, the gel composition according to the present invention comprises a sweetener and an artificial fruit flavor.

[0119] At least one flavoring agent is preferably incorporated into the immunogenic composition according to the present invention at a concentration of 0.1% to 0.5% by weight.

[0120] In one aspect, the gel composition according to the present invention further comprises one or more colorants.

[0121] The term dye may also be used in the compositions of the invention described to provide visual cues to piglets and / or visual verification to animal handlers that the composition is present, uniformly applied and adequately adherent. Preferably, the gel composition according to the present invention further comprises one or more dyes capable of attracting pigs. The dyes are well known to those skilled in the art and include pigments or dyes or a combination thereof. Suitable dyes include, but are not limited to, FD&C dyes such as FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3, Orange B, Citric Red No. 2, FD&C Petition 870250088147, dated 09 / 29 / 2025, pp. 248 / 315 28 / 79 Red No. 2, FD&C Red No. 3, FD&C Red No. 40, FD&C Yellow No. 5, and FD&C Yellow No. 6.

[0122] FD&C Blue No. 1 is the dye called Brilliant Blue FCF, also indicated by the number E133.

[0123] FD&C Blue No. 2 is the dye called indigotine, also indicated by the number E132.

[0124] FD&C Green No. 3 is the Fast Green FCF dye, also indicated by the number E143.

[0125] FD&C Red No. 2 is the Amaranth dye, also indicated by the number E123.

[0126] FD&C Red No. 3 is the dye erythrosine, also indicated by the number E127.

[0127] FD&C Red No. 40 is the Red dye Allura AC, also indicated by the number E129.

[0128] FD&C Yellow No. 5 is the dye tartrazine, also indicated by the number E102,

[0129] FD&C Yellow No. 6 is the Sunset Yellow FCF dye, also designated by the number E 110.

[0130] The gel composition according to the present invention preferably comprises at least one dye selected from the group consisting of brilliant blue FCF, indigotine, fast green FCF, amaranth, erythrosine, Allura red AC, tartrazine, sunset yellow FCF.

[0131] Preferably, the gel composition according to the present invention comprises the dyes brilliant blue FCF and tartrazine. Thus, at least one dye, as mentioned in this document, is preferably a mixture of brilliant blue FCF and tartrazine. Then, in one aspect Petition 870250088147, dated 09 / 29 / 2025, pp. 249 / 315 29 / 79 preferred, the gel composition according to the present invention has a green color.

[0132] According to another preferred aspect, the gel composition according to the present invention comprises water and / or an adhesion-enhancing agent and / or a pH-adjusting agent and / or a stabilizer.

[0133] In one aspect, at least one adhesion-enhancing agent is a hydrophilic polymer or copolymer that is linear or branched, cross-linked, non-biodegradable, or is selected from the group consisting of maltodextrins, hemicellulose extract, hemicellulose, xanthan gum, guar gum, pectins, gums, guar derivatives, chitosan, dextran, carrageenans, starch, polyethylene glycol, albumin, cellulose ethers, hyaluronic acid, carboxymethylhydroxyethylcellulose, hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), carboxymethylcellulose (CMC), gelatins, vinyl acetates, polyvinylpyrrolidone, polyvinylpyrrolidone-vinyl acetate copolymers, polyvinyl alcohols, polyphosphoesters, N-(2-hydroxypropyl)methacrylamide copolymers (HPMA), acids Polyacrylics, polyacrylamides, polyoxazolines, divinyl ether-maleic anhydride, polyphosphazenes, including derivatives and substitutions and salts of any of the foregoing, and combinations thereof.

[0134] In one aspect, at least one adhesion-enhancing agent is one or more starch- and / or hemicellulose-based adhesion-enhancing agents. Petition 870250088147, dated 09 / 29 / 2025, pages 250 / 315 30 / 79

[0135] In another aspect, at least one adhesion-enhancing agent(s) is / are maltodextrins and / or hemicellulose extract.

[0136] In one aspect, the gel composition according to the present invention comprises maltodextrin.

[0137] In one aspect, the gel composition according to the present invention comprises hemicellulose extract.

[0138] Preferably, the hemicellulose extract mentioned in this document comprises xanthan.

[0139] In some aspects, in the immunogenic composition according to the present invention, at least one adhesion-enhancing agent is at a final concentration (w / v) of about 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9% 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26% 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38% 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, or 49%, or any intervals between these, including, for example, from about 0.5% to 15% p / v, from about 0.5% to 10% p / v, from about 0.5% to 5% p / v, from about 0.5% to 2% p / v.

[0140] In one aspect, in the immunogenic composition according to the present invention, the adhesion-enhancing agent is at a final concentration (w / v) of about 0.5% to 15% w / v.

[0141] According to another preferred aspect, the gel composition according to the present invention comprises one or more pharmacologically acceptable excipients, in particular selected from the group consisting of Petition 870250088147, dated 09 / 29 / 2025, pp. 251 / 315 31 / 79 in stabilizers, pH adjusting compositions, alcohols, glycols, glycerols and glycerins, lanolin and its derivatives, fatty acids and their derivatives, fatty alcohols and their derivatives, and fatty esters and their derivatives, or combinations thereof.

[0142] Preferably, the pharmacologically acceptable excipient(s) is / are selected from the group consisting of propylene glycol (PG), propylene glycol monolaurate (PGML), propylene glycol capriate, polyethylene glycol monolaurate (PEGML), glycerol monolaurate (GML), methylformamide (DMF), allantoin, urazol, N,N-dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), decyl methyl sulfoxide, lecithin, polyoxylglycerides, the 1-substituted azacycloheptan-2-ones, particularly 1-ndodecylcycloazacycloheptan-2-one, alcohols and oils safe for swine consumption, such as vegetable oils.

[0143] In particular, the gel composition according to the present invention comprises a stabilizer, wherein the stabilizer is preferably propylene glycol.

[0144] A “pH adjusting agent” is normally added to bring the pH of the composition to the desired value. Desirable pH values ​​are between about 6 and about 8. The immunogenic compositions of the present invention can therefore be formulated to have a pH value ranging from about 6 to about 8, or from about 6.5 to about 7.5. Suitable pH adjusting agents include, but are not limited to, one or more adipic acids, glycines, citric acids, calcium hydroxides, magnesium aluminometasilicates, disodium phosphate, sodium phosphate, phosphate of Petition 870250088147, dated 09 / 29 / 2025, pp. 252 / 315 32 / 79 potassium, potassium chloride, sodium citrate, calcium lactate, sodium succinate, sodium glutamate, sodium bicarbonate and potassium bicarbonate, and combinations thereof.

[0145] As used in this document, a stabilizer is an agent that helps stabilize the active agent in the immunogenic composition according to the present invention. The stabilizer includes, but is not limited to, reducing agents. Stabilizers that may be used include sodium thiosulfate, sodium metabisulfite, sodium bisulfite, sodium sulfite, sulfur dioxide, ammonium bisulfite, and ammonium thiosulfate. Sodium thiosulfate is preferred because it has a high neutralizing capacity and is considered safe and non-corrosive.

[0146] The term stabilizer also includes chelating agents. Chelating agents are optionally added to the gel composition according to the present invention to improve the preservative or preservative system. Preferred chelating agents are mild agents, such as, for example, ethylenediaminetetraacetic acid (EDTA), EDTA derivatives, or any combination thereof.

[0147] Suitable stabilizers or preservatives for use in the immunogenic compositions of the present invention include, without limitation, one or more alkanols, disodium EDTA (ethylenediaminetetraacetate), EDTA salts, EDTA fatty acid conjugates, isothiazolinone, parabens such as methylparaben and propylparaben, propylene glycols, sorbates, Petition 870250088147, dated 09 / 29 / 2025, pp. 253 / 315 33 / 79 Urea derivatives, such as diazolindinyl urea, or any combinations thereof.

[0148] In some aspects of the invention, in the immunogenic composition according to the present invention, at least one pharmacologically acceptable excipient is in a final concentration (v / v) of about 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48% or 49%, or any intervals between them, including, for example, about 5% to about 10%, about 10% to about 15%, about 12% to about 13%, about 15% to about 20%, about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45% and about 45% to about 50%.

[0149] In one aspect of the present invention, the gel composition according to the present invention comprises water, an adhesion-enhancing agent and a stabilizer.

[0150] In one aspect, the gel composition according to the present invention comprises water, an adhesion-enhancing agent, a stabilizer, and a pH-adjusting agent.

[0151] In one aspect, the gel composition according to the present invention comprises water, maltodextrins, hemicellulose extract and propylene glycol.

[0152] In another aspect, the gel composition according to the present invention comprises water, Petition 870250088147, dated 09 / 29 / 2025, pp. 254 / 315 34 / 79 maltodextrins, cellulose, a gum and a stabilizer, preferably a propylene glycol.

[0153] In one aspect, the gel composition according to the present invention comprises water, maltodextrins, hemicellulose extract, propylene glycol and artificial colorant.

[0154] According to a particularly preferred aspect, the gel composition according to the present invention comprises or consists of: - water, - maltodextrins, - propylene glycol, - hemicellulose extract, - one or more dyes and - one or more flavoring agents.

[0155] According to another preferred aspect, the immunogenic composition according to the present invention comprises or contains one or more excipients acceptable for veterinary use.

[0156] In one aspect of the present invention, one or more excipients acceptable for veterinary use is / are a diluent.

[0157] The diluent may include water, saline solution, dextrose, ethanol, glycerol and the like. Isotonic agents may include sodium chloride, dextrose, mannitol, sorbitol and lactose, among others. Stabilizers include albumin and alkaline salts of ethylenediaminetetraacetic acid, among others. Petition 870250088147, dated 09 / 29 / 2025, pages 255 / 315 35 / 79

[0158] In one aspect of the present invention, the carrier(s) acceptable for veterinary use is / are a physiological buffer.

[0159] In one aspect of the present invention, the acceptable carrier(s) for veterinary use is / are phosphate-buffered saline solution.

[0160] Preferably, the acceptable carrier(s) for veterinary use is / are selected from the group consisting of solvents, dispersing media, coatings, stabilizing agents, diluents, preservatives, antibacterial and antifungal agents, isotonic agents, adsorption retardants and combinations thereof.

[0161] Preferably, the immunogenic composition according to the present invention further comprises a sucrose gelatin stabilizer.

[0162] Preferably, the immunogenic composition may also include one or more other immunomodulatory agents, such as, for example, interleukins, interferons or other cytokines.

[0163] According to another aspect, the immunogenic composition according to the present invention comprises or contains an adjuvant. It is understood, in the context of the present invention, that the person skilled in the art will preferably choose an adjuvant suitable for oral administration. Thus, the immunogenic composition, according to the present invention, preferably comprises or contains an adjuvant suitable for oral administration. Petition 870250088147, dated 09 / 29 / 2025, pp. 256 / 315 36 / 79

[0164] According to another aspect, the immunogenic composition, according to the present invention, comprises or contains at least one immunogenic substance other than the non-replicating viral antigen according to the present invention.

[0165] In one aspect, the non-replicating viral antigen according to the present invention is a recombinant ORF2 protein of PCV2a and said at least one immunogenic substance other than said viral antigen is a recombinant ORF2 protein of PCV2d, and wherein, preferably, said ORF2 protein of PCV2a comprises or consists of an amino acid sequence having at least 95%, preferably at least 98%, more preferably at least 99% or, in particular, 100% sequence identity with the sequence of SEQ ID NO:1, and said ORF2 protein of PCV2d comprises or consists of an amino acid sequence having at least 95%, preferably at least 98%, more preferably at least 99% or, in particular, 100% sequence identity with the sequence of SEQ ID NO:2.

[0166] According to a particularly preferred aspect, the immunogenic composition, according to the present invention, comprises said ORF2 protein of PCV2a and said ORF2 protein of PCV2d in a molar ratio of about 1:1.

[0167] With reference to the clauses disclosed later, in some embodiments, the present invention provides the method according to any of clauses 20 Petition 870250088147, dated 09 / 29 / 2025, pp. 257 / 315 37 / 79 to 26 and 31 to 58, wherein the aforementioned method is a method to reduce one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject.

[0168] According to a preferred aspect, the immune response mentioned in this document is a protective immune response, in particular a protective immune response against a virus, and the virus is of the species that has a genome that codes - the non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen.

[0169] The present invention also provides a method for - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method comprising administering orally to the subject an immunogenic composition comprising an effective amount of a non-replicating viral antigen.

[0170] Preferably, a “viral infection”, as mentioned in this document, is an infection by a virus, the virus being of a species that has a genome that codes - the non-replicating viral antigen according to the present invention, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen according to the present invention. Petition 870250088147, dated 09 / 29 / 2025, pages 258 / 315 38 / 79

[0171] In one aspect, the immunogenic composition according to the present invention is administered orally to the subject.

[0172] The invention also provides methods for - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, wherein the methods comprise the steps of: - add an immunogenic composition comprising non-replicating viral antigen to the subject's liquid food or drinking water, and - to allow the subject to self-administer the immunogenic composition.

[0173] Preferably, in this context of the present invention, the immunogenic composition according to the present invention is added to the subject's drinking water.

[0174] The term self-administer or self-administration, as used in this document, means, in particular, that the subject drinks the liquid food or drinking water and thus consumes orally the immunogenic composition according to the present invention.

[0175] Thus, the term self-administration, as used in this document, is, in particular, equivalent to oral self-administration.

[0176] In some embodiments, the invention also provides methods for - to induce an immune response against PCV2 in a subject, or Petition 870250088147, dated 09 / 29 / 2025, pp. 259 / 315 39 / 79 - to reduce one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject, wherein the methods comprise the steps of: - add an immunogenic composition comprising the non-replicating PCV2 antigen to the subject's liquid food or drinking water, and - to allow the subject to self-administer the immunogenic composition, and wherein, with reference to the clauses disclosed below, the said non-replicating PCV2 antigen is preferably a recombinant protein, as specified in any of clauses 20 to 26 and 31.

[0177] All the above-mentioned methods for inducing an immune response in a subject and / or for reducing one or more clinical signs, viral load and / or viremia caused by viral infection in a subject will also be referred to hereinafter as “the methods according to the present invention”.

[0178] According to one aspect, the methods according to the present invention consist of administering orally only one dose of said immunogenic composition to said subject or, respectively, said immunogenic composition is added only once to the subject's liquid food or drinking water.

[0179] According to another preferred aspect, in the methods according to the present invention, the subject is not pre-vaccinated with a vaccine against a virus, and the Petition 870250088147, dated 09 / 29 / 2025, pp. 260 / 315 40 / 79 virus is of the species that possesses a genome that encodes the antigenic determinant of the aforementioned viral antigen.

[0180] In some embodiments of the present invention, the subject is a subject without vaccination against PCV2.

[0181] In one aspect, in the methods according to the present invention - the aforementioned immune response, or The aforementioned reduction of one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject is achieved by administering the immunogenic compound.

[0182] In another aspect, in the methods according to the present invention - the aforementioned immune response, or - the aforementioned reduction of one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject is obtained without additional administration of a vaccine against a virus to the subject, the virus being of a species that has a genome encoding the antigenic determinant of the viral antigen included in the aforementioned immunogenic composition.

[0183] In a preferred aspect of the methods according to the present invention, the subject is preferably an animal, in particular a pig.

[0184] In another preferred aspect of the methods according to the present invention, the subject is a piglet or a sow.

[0185] The invention further provides a liquid antigen concentrate for dilution in drinking water or in Petition 870250088147, dated 09 / 29 / 2025, pp. 261 / 315 41 / 79 liquid foods, wherein 1 mL of said concentrate comprises approximately 100 to 800 μg of non-replicating viral antigen, in particular of any of the non-replicating viral antigens described in this document in the context of the present invention.

[0186] Preferably, the said concentrate, which is also referred to as “liquid antigen concentrate according to the present invention” hereafter, allows simply establishing a defined volume of drinking water or liquid feed containing a desired concentration of non-replicating viral antigen, depending on the self-administered subject and its environment. For example, pigs generally drink 8 to 12% of their body weight per day, depending on the ambient temperature. Thus, the volume of drinking water consumed during a given period per pig can be calculated (e.g., based on pre-measured drinking water intake during a given period of the previous day, around the time of the planned vaccination), and an adequate volume of drinking water containing sufficient antigen can be provided to ensure that the pigs self-administer at least the desired dose of the antigen within a given period.

[0187] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 150 to 800 μg of non-replicating viral antigen.

[0188] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 200 to 800 μg of non-replicating viral antigen. Petition 870250088147, dated 09 / 29 / 2025, pp. 262 / 315 42 / 79

[0189] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 250 to 800 pg of non-replicating viral antigen.

[0190] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 300 to 800 pg of non-replicating viral antigen.

[0191] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 400 to 800 pg of non-replicating viral antigen.

[0192] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 500 to 800 pg of non-replicating viral antigen.

[0193] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 600 to 800 pg of non-replicating viral antigen.

[0194] In one aspect, 1 mL of the liquid antigen concentrate according to the present invention comprises about 700 to 800 pg of non-replicating viral antigen.

[0195] The term liquid, as used in this document, has the common meaning in the art and refers, in particular, to a state of matter at room temperature (25°C) and atmospheric pressure (760 mmHg).

[0196] The invention further provides a method for enabling self-immunization against a virus by a subject, comprising the step of diluting a liquid antigen concentrate comprising non-replicating viral antigen, in particular non-replicating viral antigen according to the present invention, in the subject's drinking water, and wherein the Petition 870250088147, dated 09 / 29 / 2025, pp. 263 / 315 43 / 79 referred to as concentrate is, in particular, a liquid antigen concentrate according to the present invention.

[0197] The invention also provides a container containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added, in particular non-replicating viral antigen according to the present invention, and wherein said container is also referred to as the “container of the present invention” hereafter. In particular, the container according to the present invention is a container containing potable water to which a liquid antigen concentrate according to the present invention has been added.

[0198] The container in question may be any container used to provide drinking water to a subject. Preferably, the container in question is selected from the group consisting of a bowl, a vase and a barrel and / or the container in question is located in the housing environment of a subject to be vaccinated.

[0199] The invention also relates to a kit for immunizing a subject, comprising - a liquid antigen concentrate comprising a non-replicating viral antigen, in particular a non-replicating viral antigen according to the present invention; and - Instructions for diluting said liquid antigen concentrate in drinking water or liquid food to be consumed by the subject. Preferably, said liquid antigen concentrate is a liquid antigen concentrate according to the present invention. Petition 870250088147, dated 09 / 29 / 2025, pp. 264 / 315 44 / 79

[0200] With reference to the clauses disclosed below, the subject in question, as mentioned in this document in the context of the method for enabling self-immunization against a virus, the immunization kit and the container containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added, is preferably a subject as specified in any of clauses 97 to 99.

[0201] More preferably, the subject mentioned in this document is a piglet. EXAMPLES

[0202] The following examples are for illustrative purposes only and should not limit the scope of the claims in any way. EXAMPLE 1 Results of the oral vaccination study against PCV2. Objective:

[0203] To investigate whether the virus-like particle (VLP) of porcine circovirus type 2 (PCV2) is immunogenic when administered orally, thus being an oral vaccine to prevent PCV2 disease in swine. Methods:

[0204] To investigate the immunogenicity of the oral vaccine against porcine circovirus type 2, virus-like particle, for swine, an experiment was conducted with two treatment groups. SPF pigs, approximately six weeks old on day 0 of the study, were randomly assigned to treatment group 1) Control no Petition 870250088147, dated 09 / 29 / 2025, pages 265 / 315 45 / 79 vaccinated and 2) Group vaccinated with oral VLP. These groups consisted of 7 and 10 pigs, respectively.

[0205] Pigs in each treatment group were divided into two pens. On day 0 of the study, pigs in the oral VLP vaccine group received, orally, 1 mL 300 pg / mL of porcine circovirus type 2d, killed baculovirus vector expressed by virus-like particle, i.e., recombinant baculovirus expressed by the ORF2 protein of PCV2d (SEQ ID NO:2 (corresponds to SEQ ID NO:1 of WO2015051099)). The ORF2 protein of PCV2d was produced as described in WO2015051099 (Examples 1 to 3) and then subjected to further processing as set out in WO 2019191005 (Example 1, without mixing with a carbomer solution (adjuvant)).

[0206] This vaccine did not contain an adjuvant. On study day 0, before vaccination, on study day 14, and on study day 23, blood was individually collected from each pig for serum collection and antibody measurement. On day 23 after vaccination, blood was collected from all pigs for peripheral blood mononuclear cell (PBMC) extraction to assess PCV2-specific T-cell immunity, following the protocol of Koinig HC et al. Vet Res. 46:20 (2015). Serum IgM quantification was performed using the INGEZIM Circovirus IgG / IgM ELISA kit. On study day 22, oral fluids were also collected to assess anti-PCV2 IgA, IgG, and IgM antibodies. Serum IgG quantification, along with IgA, IgM, and IgG in oral fluids, was performed following the methods described in Prickett et al. Transbound Emerg Dis. 58(2):121-7 (2011). The antigen Petition 870250088147, dated 09 / 29 / 2025, pp. 266 / 315 The 46 / 79 antigen used for the assay by Prickett et al. (2011) was the same PCV2d antigen used to immunize the pigs. All blood samples were also subjected to PCV2 viremia testing by PCR. Results:

[0207] PCV2 viremia was not detected in any pigs. The oral vaccine was well tolerated and no adverse events were observed. Antibody results revealed that the oral VLP vaccine led to an increase in anti-PCV2 IgM antibody levels, an effect not observed in the unvaccinated control group (Figure 1). Although both groups had similar IgM antibody levels on day 0 of the study, before vaccination, antibody levels in the oral VLP vaccine group were significantly higher than in the unvaccinated control group at 14 (p = 0.01) and 23 days after vaccination (p = 0.03) (Figure 1). In addition to IgM, a significant increase in serum anti-PCV2 IgG antibody levels was also observed with oral vaccination.Twenty-three days after vaccination, the oral VLP vaccine group showed a mean S / P value of 0.665, while the unvaccinated control group showed an antibody concentration approximately ten times lower, with a mean S / P value of 0.066 (p=0.034) (Figure 2). To better assess the immune response, specific anti-PCV2 antibodies were measured in oral fluids after vaccination. This analysis revealed much higher quantities of anti-PCV2 antibodies of the IgA, IgG, and IgM classes in pigs from the oral VLP vaccine group (Figure 3). The unexpected observation of a substantial increase in IgA is indicative of a strong induced mucosal immune response. Petition 870250088147, dated 09 / 29 / 2025, pp. 267 / 315 4Ί / Ί9 by the orally administered PCV2 subunit vaccine. Furthermore, the observation of IgG was surprising, as it was not expected that an orally administered PCV2 subunit vaccine would lead to a significant serological response.

[0208] Analysis of cellular immunity revealed that pigs in the oral VLP vaccine group developed T cells specific for the PCV2 antigen, while pigs in the unvaccinated control group did not. At 23 days post-vaccination, the oral VLP vaccine group had CD4+ T cells producing interferon gamma and tumor necrosis factor specific for the PCV2 antigen, while the unvaccinated control group did not (Figure 4). Conclusion:

[0209] These results demonstrate that oral administration of porcine circovirus type 2 virus-like particles was immunogenic in pigs, inducing both cellular and humoral immune responses, thus representing a method and a vaccine to prevent diseases caused by PCV2 in pigs. EXAMPLE 2 Results of the PCV2 VLP gel administration study. Objective:

[0210] To investigate whether the virus-like particle (VLP) of porcine circovirus type 2 (PCV2) is immunogenic when administered to pigs via a gel, thus being an oral and mucosal vaccine to prevent diseases associated with -aa PCV2 in swine. Methods: Petition 870250088147, dated 09 / 29 / 2025, pages 268 / 315 48 / 79

[0211] To investigate the immunogenicity of the porcine circovirus type 2 virus-like particle, administered via gel to pigs, an experiment was conducted with two treatment groups.

[0212] SPF pigs approximately 6 weeks old on day 0 of the study were randomly assigned to treatment group 1) Unvaccinated control and 2) VLP gel vaccinated group. These groups consisted of 7 and 10 pigs, respectively.

[0213] On day 0 of the study, pigs in the group vaccinated with VLP gel received an immunogenic composition of the present invention, such that, for each pig, 100 mL of the finally prepared VLP gel vaccine was administered, containing a total of 300 pg of the PCV2d ORF2 protein expressed by recombinant baculovirus (SEQ ID NO:2 (corresponds to SEQ ID NO:1 of WO2015051099)), said viral antigen being also referred to herein as “Porcine circovirus, type 2d, killed baculovirus vector expressed by virus-like particle” or “PCV2 VLP”, respectively. The ORF2 protein of PCV2d was produced as described in WO2015051099 (Examples 1 to 3) and then subjected to downstream processing as set out in WO 2019191005 (Example 1, without mixing with a carbomer solution (adjuvant)).

[0214] The Gel VLP vaccine finally prepared was manufactured by mixing commercially available Underline® gel concentrate (Animal Science Products, Nacogdoches, TX (USA)) - which has the following ingredients: water, maltodextrins, propylene glycol, hemicellulose extract, Petition 870250088147, dated 09 / 29 / 2025, pp. 269 / 315 49 / 79 artificial color, natural and artificial flavor - according to the manufacturer's specifications with PCV2 VLP in the following proportions: 1 part Underline® gel concentrate was mixed with 2 parts cold PCV2 VLP liquid.

[0215] The VLP Gel vaccine was placed in the pig housing, adding a total of 500 mL of the same (containing 1,500 pg of PCV2 VLP) per pen with five pigs. This composition was added to two bowls (porridge feeders) per pen to allow the pigs to consume the gel vaccine mixture on their own. This vaccine did not contain an adjuvant. Twenty-three days after vaccination, all pigs had blood collected for peripheral blood mononuclear cell (PBMC) extraction to assess PCV2-specific T-cell immunity, following the protocol of Koinig HC et al. Vet Res. 46:20 (2015). All blood samples were also subjected to PCR viremia testing for PCV2. Results:

[0216] PCV2 viremia was not detected in any pigs. The pigs were immediately attracted to the VLP gel mixture and consumed it entirely. This allowed for the immunization of the pigs against PCV2 without the need to handle each pig individually, drastically reducing the labor and time required to immunize and manage the animals. The vaccine composition was well tolerated and no adverse events were observed.

[0217] Analysis of cellular immunity revealed that pigs in the Gel VLP vaccine group developed T cells. Petition 870250088147, dated 09 / 29 / 2025, pages 270 / 315 50 / 79 specific for the PCV2 antigen, while pigs in the unvaccinated control group did not develop them. At 23 days after vaccination, the Oral VLP vaccine group had CD4+ T cells producing interferon gamma and tumor necrosis factor specific for the PCV2 antigen, while the unvaccinated control group did not (Figure 5). Conclusion:

[0218] Porcine circovirus type 2, virus-like particle, when combined with a semi-solid, liquid and gel formulation for consumption, was immunogenic for pigs, therefore being a method and a vaccine to prevent disease caused by PCV2 in pigs. EXAMPLE 3 Results of the efficacy evaluation of the oral vaccine against PCV2 Objective:

[0219] The objective of this study was to evaluate the efficacy of orally administered virus-like particles (VLPs) of porcine circovirus type 2 (PCV2), containing VLPs of PCV type 2a and PCV type 2d, against a challenge with PCV2d in swine. Methods:

[0220] To investigate the efficacy of the oral vaccine against porcine circovirus type 2, virus-like particle, in swine, an experiment was conducted with four treatment groups. These treatment groups consisted of a placebo group and groups that received different concentrations of PCV2 VLP. Cesarean-delivered, colostrum-deprived, and colostrum-deprived a (CDCD) pigs, approximately three weeks old on day 0 of the study, were Petition 870250088147, dated 09 / 29 / 2025, pp. 271 / 315 51 / 79 randomly assigned to treatment groups: T01 Placebo, unvaccinated and challenged; T02 Oral 1x, vaccinated and challenged; T03 Oral 5x vaccinated and challenged; T04 Oral 10x vaccinated and challenged. Each group consisted of 25 pigs.

[0221] Pigs from each treatment group were mixed between pens. On day 0 of the study, pigs in the orally vaccinated groups received, via oral drainage, a 1 mL dose of different antigen concentrations. Treatment T02 Oral 1x received 15 pg of PCV type 2a and 15 pg of PCV type 2d VLP; Treatment T03 Oral 5x received 75 pg of PCV type 2a and 75 pg of PCV type 2d VLP; and treatment T04 Oral 10x received 150 pg of PCV type 2a and 150 pg of PCV type 2d VLP.These antigens were (i) Porcine circovirus, type 2d, killed baculovirus vector expressed by virus-like particle, i.e., recombinant baculovirus expressed by the PCV2d ORF2 protein (SEQ ID NO:2 (corresponds to SEQ ID NO:1 of WO2015051099)), which had been produced as described above in Example 1, and (ii) Porcine circovirus, type 2a, killed baculovirus vector-like particle expressed by virus-like particle, i.e., PCV2a ORF2 protein expressed by recombinant baculovirus (SEQ ID NO:1 (corresponds to SEQ ID NO:1 of WO 2019191005)), which had been produced as described in Example 1 of WO 2019191005 (in “Production of the PCV2 ORF2 protein – Upstream processing”), and was then subjected to downstream processing as set out in WO 2019191005. (Example 1, without mixing with a carbomer solution (adjuvant)). The placebo group received the solution. Petition 870250088147, dated 09 / 29 / 2025, pp. 272 / 315 52 / 79 saline with the same route and volume as the groups vaccinated orally on day 0 of the study.

[0222] The animals were challenged on day 28 of the study. The challenge consisted of intramuscular (IM) administration of 1.0 mL in the left neck and 1.0 mL of the same material intranasally (IN) in one nostril, using a sterile syringe. This challenge targeted a dose of 5.0 log10TCID50 Porcine Circovirus type 2d / 2 mL per pig. Blood was collected before vaccination (day -2 of the study), before the challenge (day 27 of the study), as well as weekly after the challenge on days 35, 42, and 49 of the study. The study ended on day 49, twenty-one days after the challenge. PCV2 viremia was quantified in the serum of the collected blood samples by PCR. Results:

[0223] Prior to the challenge, PCV2 viremia was not detected in any pigs (Figure 6). The placebo group T01 developed PCV2 viremia after the challenge, which peaked on day 49 of the study, with an average of 7.48 log10 genomic copies of PCV2 per mL. Oral administration of PCV2 VLP had a clear protective effect in reducing the consequences of PCV2 infection, as evidenced by a significant reduction in viremia. This reduction in viremia occurred in all three orally vaccinated treatment groups, which were administered different concentrations of the PCV2 VLP antigen (Figure 6). On day 49 of the study, the T02 Oral 1x group led to a reduction of 1.676 log10 genomic copies of PCV2 / mL of viremia compared to the T01 Placebo group (Figure 6). The effect of antigen concentration Petition 870250088147, dated 09 / 29 / 2025, pp. 273 / 315 53 / 79 PCV2 VLP was also observed, as the groups that received higher antigen concentrations showed lower viremia levels. This further highlights the immunogenic and protective effect of the orally administered PCV2 VLP antigen. On days 42 and 49 of the study, there was a significant difference between the serum PCV2 levels of the T02 Oral 1x and T04 Oral 10x groups. These differences were 2,390 log10 and 1,951 log10 genomic copies of PCV2 per mL, respectively. The T03 Oral 5x group showed intermediate mean viremia levels between those of the T02 Oral 1x and T04 Oral 10x treatment groups at all three time points after the challenge (Figure 6). The T04 Oral 10x group showed the lowest viremia levels. A lower level of PCV2 viremia was found between the T04 Oral 10x group and the T01 Placebo group at all time points after the challenge (Figure 6).The difference in PCV2 viremia levels between the two treatments was 1.435 log10, 3.432 log10, and 3.627 log10 genomic copies of PCV2 / mL, respectively, on days 35, 42, and 49 of the study. Conclusion:

[0224] These results demonstrate that oral administration of porcine circovirus type 2 virus-like particles mitigated infection and therefore protected against infection, thus being a method and a vaccine to prevent disease caused by PCV2 in pigs. LIST OF FIGURES:

[0225] Figure 1 (“Fig. 1): Mean S / P value of PCV2-specific IgM in the Negative Control and Oral Vaccine (OV) groups at 0, 14, and 23 days post-vaccination. dpv = days Petition 870250088147, dated 09 / 29 / 2025, pp. 274 / 315 54 / 79 after vaccination; different letters indicate statistical significance within each time point (p<0.05). Within the bar pairs shown in the graph, the left bar is designated as “Unvaccinated Control” and the right bar is designated as “Oral VLP Vaccine”.

[0226] Figure 2 (“Fig. 2”). Mean S / P value of PCV2-specific IgG in the Negative Control and Oral VLP Vaccine groups 0 days post-vaccination and 14 days post-vaccination. dpv = days post-vaccination. Different letters indicate statistical significance within each time point (p<0.05). In the bar pairs shown in the graph, the left bar is designated as “Unvaccinated Control” and the right bar is designated as “Oral VLP Vaccine”.

[0227] Figure 3 (“Fig. 3”): Mean S / P value of PCV2-specific IgA, IgG, and IgM in the Negative Control and Oral VLP Vaccine groups 22 days after vaccination, quantified in oral fluids. Within the bar pairs shown in the graph, the left bar is designated as “Unvaccinated Control” and the right bar is designated as “Oral VLP Vaccine”.

[0228] Figure 4 (“Fig. 4”): Percentage of PCV2 antigen-specific CD4+ T cells positive for interferon gamma (IFNg) and tumor necrosis factor alpha (TNFa) measured in the blood of pigs 23 days after vaccination.

[0229] Figure 5 (“Fig. 5”): Percentage of PCV2 antigen-specific CD4+ T cells positive for interferon gamma (IFNg) and tumor necrosis factor alpha (TNFa) measured in the blood of pigs 23 days after vaccination. Petition 870250088147, dated 09 / 29 / 2025, pages 275 / 315 55 / 79

[0230] Figure 6 (“Fig. 6): Average number of PCV2 genomic copies in the serum of different treatment groups and at different times. Sequences included in the sequence list: SEQ ID NO:1

[0231] SEQ ID NO:1 corresponds to the sequence of an ORF2 protein from PCV2a (233 amino acid residues in length). SEQ ID NO:1 has the amino acid sequence (in the one-letter code for amino acid residues, from the N-terminal to the C-terminal, including an N-terminal methionine residue (M) at the amino acid position): MTYPRRRYRRRRHRPRSHLGQILRRRPWLVHPRHRYRWRRKNGIFNTRLSRTFG YTVKAT TVTTPSWAVDMMRFNIDDFVPPGGGTNKISIPFEYYRIRKVKVEFWPCSPITQG DRGVGS TAVILDDNFVTKATALTYDPYVNYSSRHTIPQPFSYHSRYFTPKPVLDSTIDYF QPNNKR NQLWLRLQTSRNVDHVGLGTAFENSKYDQDYNIRVTMYVQFREFNLKDPPLEP SEQ ID NO:2

[0232] SEQ ID NO:2 corresponds to the sequence of an ORF2 protein from PCV2d (234 amino acid residues in length). SEQ ID NO:2 has the amino acid sequence (in the one-letter code for amino acid residues, from the N-terminal to the C-terminal, including an N-terminal methionine residue (M) at the amino acid position): MTYPRRRFRRRRRHRPRSHLGQILRRRPWLVHPRHRYRWRRKNGIFNTRLSRTIG YTVKKT TVTTPSWNVDMMRFNINDFLPPGGGSNPLTVPFEYYRIRKVKVEFWPCSPITQG DRGVGS Petition 870250088147, dated 09 / 29 / 2025, pp. 276 / 315 56 / 79 TAVILDDNFVTKANALTYDPYVNYSSRHTITQPFSYHSRYFTPKPVLDRTIDYF QPNNKR NQLWLRLQTTGNVDHVGLGTAFENSIYDQDYNIRITMYVQFREFNLKDPPLNPK SEQ ID NO:3

[0233] SEQ ID NO:3 corresponds to the sequence of a PPV VP2 (with 579 amino acid residues in length). SEQ ID NO:3 has the amino acid sequence (and a letter code for amino acid residues, from N-terminal to C-terminal, including an N-terminal (M) methionine residue at position 1 of the amino acid): MSENVEQHNPINAGTELSATGNESIGGGGGGGRGSIGVGVSTGSFNNQTEFQY LGEGLV RITAHASRLIHLNMPEHETYKRIHVLNSESSGVAGQMVQDDAHTQMVTPWSLIDA NAWGVW FNPADWQLISNNMTEINLVSFEQEIFNVVLCTITESATSPPTKIYNNDLTASLM VALDTN NTLPYTPAAPRSETLGFYPWLPTKPTQYRYYLSCTRNLNPPTYTGQSEQITDSI QTGLHS DIMPHYTHINEAVPIHLLRTGDEFSTGIYHFDTKPLKLTHSWQTNRSLGLPPKLLT EPTTEG DQHPGTLPAANTRKGYHQTINNSYTEATAIRPAQVGYNTPYMNFEYSNGGPFLT PIVPTA DTQYNDDEPNGAIRF™GYQHGQLTTSSQELERYTFNPQSKCGRAPKQQFNQQS PLNLQN TNNGTLLPSDPIGGKTNMHFMNTLNTYGPLTALNNTAPVFPNGQIWDKELDTDL KPRLHV TAPFVCKNNPPGQLFVKIAPNLTDDFNADSSPQQPRIITYSNFWWKGTLTFTAKM RSSNMW NPIQQHTTTAENIGNYIPTNIGGIKMFPEYSQLIPRKLY Petition 870250088147, of 29 / 09 / 2025, p. 277 / 315 57 / 79

[0234] The following clauses are also disclosed in this document. Thus, this disclosure also includes aspects characterized by the following clauses: 1. A method for - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method comprising the oral administration to the subject of an immunogenic composition comprising a non-replicating viral antigen. 2. The method, according to clause 1, wherein the said method is a method for - to induce an immune response in a subject and - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method comprising the oral administration to the subject of an immunogenic composition comprising non-replicating viral antigen. 3. The method, according to clause 1 or 2, in which the aforementioned immune response is an immune response against a virus. 4. The method, according to any of clauses 1 to 3, in which the aforementioned immune response is a protective immune response. 5. The method, according to clause 3 or 4, in which the virus in question is a virus of the species that has a genome that codes for - the non-replicating viral antigen, or Petition 870250088147, dated 09 / 29 / 2025, pages 278 / 315 58 / 79 - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen. 6. The method, according to clause 5, in which the aforementioned antigenic determinant is a protein capable of forming a virus-like particle. 7. The method, according to any of clauses 1 to 6, in which the immunogenic composition is free of replicating viral antigen. 8. The method, according to any one of clauses 1 to 7, in which the immunogenic composition consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use. 9. The method, according to any one of clauses 1 to 7, in which the immunogenic composition consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use; and at least one adjuvant. 10. The method, according to any one of clauses 1 to 7, in which the immunogenic composition consists of a non-replicating viral antigen; and one or more carriers acceptable for veterinary use; and at least one immunogenic substance other than said viral antigen. 11. The method, according to any of clauses 1 to 7, in which the immunogenic composition consists of a non-replicating viral antigen; and Petition 870250088147, dated 09 / 29 / 2025, pp. 279 / 315 59 / 79 one or more carriers acceptable for veterinary use; and at least one adjuvant; and at least one immunogenic substance other than the aforementioned viral antigen. 12. The method, according to any of clauses 1 to 11, in which the immunogenic composition additionally contains a gel composition. 13. The method, according to any one of clauses 1 to 12, in which the non-replicating viral antigen comprises or is a recombinant protein. 14. The method, according to clause 13, in which the recombinant protein is capable of forming a virus-like particle. 15. The method, according to any of clauses 1 to 14, in which the non-replicating viral antigen is a virus-like particle. 16. The method, according to any one of clauses 1 to 15, in which the non-replicating viral antigen is a virus-like particle comprising a recombinant protein. 17. The method, according to any one of clauses 13 to 16, wherein the recombinant protein is a recombinant viral capsid protein. 18. The method, according to any one of clauses 13 to 17, wherein the recombinant protein is a recombinant circovirus capsid protein. Petition 870250088147, dated 09 / 29 / 2025, pages 280 / 315 60 / 79 19. The method, according to any one of clauses 13 to 18, wherein the recombinant protein is a recombinant porcine circovirus (PCV) capsid protein. 20. The method, according to any of clauses 13 to 19, wherein the recombinant protein is a recombinant ORF2 protein from porcine circovirus type 2 (PCV2). 21. The immunogenic composition, according to clause 20, wherein the said ORF2 protein of PCV2 comprises or consists of an amino acid sequence with at least 90%, preferably at least 95%, more preferably at least 98%, even more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:1 or SEQ ID NO:2. 22. The method according to any of clauses 13 to 21, wherein the recombinant protein is selected from the group consisting of PCV2 subtype a recombinant ORF2 protein (PCV2a), PCV2 subtype b recombinant ORF2 protein (PCV2b), PCV2 subtype c recombinant ORF2 protein (PCV2c), PCV2 subtype d recombinant ORF2 protein (PCV2d), PCV2 subtype e recombinant ORF2 protein (PCV2e), PCV2 subtype f recombinant ORF2 protein (PCV2f), PCV2 subtype g recombinant ORF2 protein (PCV2g) and PCV2 subtype h recombinant ORF2 protein (PCV2h). 23. The method, according to any of clauses 13 to 22, wherein the recombinant protein is a recombinant ORF2 protein of PCV2 subtype a (PCV2a). 24. The method, according to clauses 22 or 23, in which the said ORF2 protein of PCV2a comprises or consists Petition 870250088147, dated 09 / 29 / 2025, pp. 281 / 315 61 / 79 in an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:1. 25. The method, according to any of clauses 13 to 22, wherein the recombinant protein is a recombinant ORF2 protein of PCV2 subtype d (PCV2d). 26. The method, according to clause 22 or 25, wherein the said ORF2 protein of PCV2d comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:2. 27. The method, according to any one of clauses 13 to 17, wherein the recombinant protein is a recombinant parvovirus capsid protein. 28. The method, according to any one of clauses 13 to 17 and 27, wherein the recombinant protein is a recombinant capsid protein of porcine parvovirus (PPV). 29. The method, according to any of clauses 13 to 17, 27 and 28, wherein the recombinant PPV is a recombinant viral protein 2 (VP2) of PPV. 30. The method, according to clause 29, wherein the said VP2 of the PPV comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:3. Petition 870250088147, dated 09 / 29 / 2025, pp. 282 / 315 62 / 79 31. The method, according to any one of clauses 13 to 30, wherein the said recombinant protein is a protein expressed by recombinant baculovirus. 32. The method, according to any of clauses 1 to 31, wherein the immunogenic composition comprises at least 10 pg of non-replicating viral antigen per dose, or wherein the immunogenic composition comprises at least 15 pg of non-replicating viral antigen per dose. 33. The method, according to any of clauses 1 to 32, wherein the immunogenic composition comprises at least 30 pg of non-replicating viral antigen per dose, or wherein the immunogenic composition comprises at least 50 pg of non-replicating viral antigen per dose. 34. The method, according to any of clauses 1 to 33, in which the immunogenic composition comprises at least 100 pg of non-replicating viral antigen per dose. 35. The method, according to any one of clauses 1 to 34, in which the immunogenic composition comprises at least 150 pg of non-replicating viral antigen per dose. 36. The method, according to any one of clauses 1 to 35, in which the immunogenic composition comprises at least 200 pg of non-replicating viral antigen per dose. 3. The method, according to any one of clauses 1 to 36, in which the immunogenic composition comprises at least 250 pg of non-replicating viral antigen per dose. 38. The method, according to any of clauses 1 to 3, in which a dose of the immunogenic composition has a volume of approximately 1 mL. Petition 870250088147, dated 09 / 29 / 2025, pp. 283 / 315 63 / 79 39. The method, according to any of clauses 1 to 38, in which the said immunogenic composition comprises or contains one or more carriers acceptable for veterinary use. 40. The method, according to any of clauses 1 to 39, in which one or more carriers acceptable for veterinary use are selected from the group consisting of solvents, dispersing media, coatings, stabilizing agents, diluents, preservatives, antibacterial and antifungal agents, isotonic agents, and adsorption retardants. 41. The method, according to any one of clauses 1 to 7, 9 and 11 to 40, in which the immunogenic composition comprises or contains at least one adjuvant. 42. The method, of composition according to any one of clauses 1 to 7 and 10 to 41, wherein the immunogenic composition comprises or contains at least one immunogenic substance other than the aforementioned non-replicating viral antigen. 43. The method, according to any one of clauses 1 to 7, 10 to 26 and 31 to 42, wherein the non-replicating viral antigen is a recombinant ORF2 protein of PCV2a and wherein at least one immunogenic substance other than the viral antigen is a recombinant ORF2 protein of PCV2d. 44. The method, according to clause 43, in which the said ORF2 protein of PCV2a comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably by Petition 870250088147, dated 09 / 29 / 2025, pp. 284 / 315 64 / 79 less than 99% or, in particular, 100% sequence identity with the sequence of SEQ ID NO:1, and wherein said ORF2 protein of PCV2d comprises or consists of an amino acid sequence with at least 95%, preferably at least 98%, more preferably at least 99% or, in particular, 100% sequence identity with the sequence of SEQ ID NO:2. 45. The method, according to any of clauses 12 to 44, in which the gel composition is a gel composition suitable for oral administration. 46. ​​The method, according to any of clauses 12 to 45, in which the said gel composition comprises water. 4. The method, according to any of clauses 12 to 46, in which the said gel composition is a hydrogel composition. 48. The method, according to any of clauses 12 to 4I, in which the said gel composition comprises one or more flavoring agents. 49. The method, according to any one of clauses 12 to 48, wherein the flavoring agent(s) is / are selected from the group consisting of sucrose, glucose, sodium saccharin, sodium cyclamate, xylitol, perilartein, sucralose, D-tryptophan, aspartame, dihydrochalcones, artificial fruit flavorings (e.g., strawberry flavoring), plasma protein (e.g., spray-dried plasma protein), cheese and cheese-like flavorings, milk powder, chocolate and chocolate by-products. Petition 870250088147, dated 09 / 29 / 2025, pp. 285 / 315 65 / 79 50. The method, according to any of clauses 12 to 49, in which one or more flavoring agents are capable of attracting pigs. 51. The method, according to any one of clauses 12 to 50, in which the said gel composition comprises one or more colorants, in particular one or more colorants capable of attracting pigs. 52. The method, according to any of clauses 12 to 51, in which the dye(s) is / are selected from the group consisting of FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3, Orange B, FD&C Citric Red No. 2, FD&C Red No. 2, FD&C Red No. 3, FD&C Red No. 40, FD&C Yellow No. 5 and FD&C Yellow No. 6. 53. The method, according to any of clauses 12 to 52, in which the said gel composition comprises maltodextrin. 54. The method, according to any of clauses 12 to 53, in which the said gel composition comprises hemicellulose extract. 55. The method, according to any one of clauses 12 to 54, in which the said gel composition comprises propylene glycol. 56. The method, according to any one of clauses 12 to 55, in which the said gel composition comprises or consists of: - water, - maltodextrins, - propylene glycol, - hemicellulose extract, Petition 870250088147, dated 09 / 29 / 2025, pp. 286 / 315 66 / 79 - one or more dyes and - one or more flavoring agents. 57. The method, according to any of clauses 3 to 26 and 31 to 56, in which the virus in question is PCV2. 58. The method, according to any of clauses 20 to 26 and 31 to 57, in which the immune response is an immune response against PCV2. 59. The method, according to any of clauses 20 to 26 and 31 to 58, wherein said method is a method for reducing one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject. 60. The method, according to any of clauses 1 to 59, in which the immunogenic composition is administered orally to the subject. 61. A method for inducing an immune response in a subject, wherein the method comprises the following steps: Add an immunogenic composition comprising non-replicating viral antigen to the subject's liquid food or drinking water, and allow the subject to self-administer the immunogenic composition. 62. The method, in accordance with clause 61, wherein the said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 63. The method, in accordance with clause 61 or 62, wherein the said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 16 and / or wherein the said viral antigen Petition 870250088147, dated 09 / 29 / 2025, pages 287 / 315 6Ί / Ί9 non-replicating comprises a recombinant protein, as specified in any of clauses 1Ί to 31. 64. The method, according to any of clauses 61 to 63, in which the aforementioned immune response is a protective immune response. 65. The method, according to any of clauses 61 to 63, in which the said immune response is an immune response against a virus. 66. The method, according to clause 65, in which the aforementioned immune response against a virus is an immune response against a virus, wherein the virus is of a species possessing a genome that codes for - the non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen. 6. A method for inducing an immune response against PCV2 in a subject, wherein the method comprises the following steps: Add an immunogenic composition comprising the non-replicating PCV2 antigen to the subject's liquid food or drinking water, and allow the subject to self-administer the immunogenic composition. 68. The method, according to clause 6I, wherein the said immunogenic composition is an immunogenic composition as specified in any of clauses I to 12 and 32 to 56. 69. The method, according to clause 6Ί or 68, in which the non-replicating PCV2 antigen is a protein. Petition 870250088147, dated 09 / 29 / 2025, pages 288 / 315 68 / 79 recombinant, as specified in any of clauses 20 to 26 and 31. 70. A method for reducing one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject, wherein the method comprises the following steps: Add an immunogenic composition comprising non-replicating viral antigen to the subject's liquid food or drinking water, and allow the subject to self-administer the immunogenic composition. 71. The method, in accordance with clause 70, wherein the said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 72. The method, in accordance with clause 70 or 71, wherein said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 16 and / or wherein said non-replicating viral antigen comprises a recombinant protein, as specified in any of clauses 17 to 31. 73. The method, according to any of clauses 65 to 69, wherein the said immune response is a protective immune response, in particular a protective immune response against a virus, wherein the virus is of a species possessing a genome that codes - the non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen. Petition 870250088147, dated 09 / 29 / 2025, pp. 289 / 315 69 / 79 74. A method for reducing one or more clinical signs, viral load, and / or viremia caused by a PCV2 infection in a subject, wherein the method comprises the following steps: Add an immunogenic composition comprising the non-replicating PCV2 antigen to the subject's liquid food or drinking water, and allow the subject to self-administer the immunogenic composition. 75. The method, in accordance with clause 74, wherein the said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 76. The method, in accordance with clause 74 or 75, in which the non-replicating PCV2 antigen is a recombinant protein, as specified in any of clauses 20 to 26 and 31. 77. An immunogenic composition comprising non-replicating viral antigen for use in a method for - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject. 78. The immunogenic composition for use, in accordance with clause 77, wherein the said method is a method as specified in any of clauses 1 to 6 and 57 to 60. 79. The immunogenic composition for use, in accordance with clause 77 or 78, in which the said immunogenic composition Petition 870250088147, dated 09 / 29 / 2025, pages 290 / 315 70 / 79 is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 80. The immunogenic composition for use, in accordance with any of clauses 77 to 79, wherein said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 16 and / or wherein said non-replicating viral antigen does not and comprises a recombinant protein, as specified in any of clauses 17 to 31. 81. An immunogenic composition comprising non-replicating PCV2 antigen for use in a method for - to induce an immune response against PCV2 in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject. 82. The immunogenic composition for use, in accordance with clause 81, wherein said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 83. The immunogenic composition for use, in accordance with clause 81 or 82, wherein the non-replicating PCV2 antigen is a recombinant protein, as specified in any of clauses 20 to 26 and 31. 84. Use of an immunogenic composition comprising a non-replicating viral antigen in the preparation of a medicament for use in a method for Petition 870250088147, dated 09 / 29 / 2025, pages 291 / 315 71 / 79 - to induce an immune response in a subject and / or - to reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject. 85. Use in accordance with clause 84, wherein the said method is a method as specified in any of clauses 1 to 6 and 57 to 60. 86. Use in accordance with clause 84 or 85, where the said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 56. 87. Use in accordance with any of clauses 84 to 86, wherein the said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 30. 88. Use of an immunogenic composition comprising a non-replicating PCV2 antigen in the preparation of a medicament for use in a method for - to induce an immune response against PCV2 in a subject, or - to reduce one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject. Petition 870250088147, dated 09 / 29 / 2025, pp. 292 / 315 72 / 79 89. Use, in accordance with clause 88, wherein the said immunogenic composition is an immunogenic composition as specified in any of clauses 7 to 12 and 32 to 56. 90. Use, in accordance with clause 88 or 89, wherein the said non-replicating PCV2 antigen is a recombinant protein, as specified in any of clauses 20 to 26 and 31. 91. The method, according to any of clauses 1 to 68, the immunogenic composition, according to any of clauses 77 to 83, or the use according to any of clauses 84 to 90, wherein the method consists of administering orally only one dose of said immunogenic composition to said subject. 92. The method, according to any of clauses 69 to 76, in which the said immunogenic composition is added only once to the subject's liquid food or drinking water. 93. The method, according to any of clauses 1 to 76, 91 and 92, the immunogenic composition, according to any of clauses 77 to 83 and 91, or the use according to any of clauses 84 to 91, wherein the subject is not pre-vaccinated with a vaccine against a virus, which virus is of the species that has a genome that encodes the antigenic determinant of said non-replicating viral antigen. 94. The method, according to any of clauses 1 to 76 and 91 to 93, the immunogenic composition, according to any of clauses 77 to 83, 91 and 93, or the use according to any of clauses 84 to 91 and 93, where the subject is a subject without prior vaccination against PCV2. Petition 870250088147, dated 09 / 29 / 2025, pp. 293 / 315 73 / 79 95. The method, according to any one of clauses 1 to 76 and 91 to 94, the immunogenic composition, according to any one of clauses 77 to 83, 91, 93 and 94, or the use according to any one of clauses 84 to 91, 93 and 94, wherein - the aforementioned immune response, or The aforementioned reduction of one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject is achieved by the aforementioned administration of the aforementioned immunogenic composition. 96. The method, according to any one of clauses 1 to 68 and 91 to 95, the immunogenic composition, according to any one of clauses 77 to 83, 91 and 93 to 95, or the use according to any one of clauses 84 to 91 and 93 to 95, wherein - the aforementioned immune response, or - The reduction of one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject is achieved without additional administration of a vaccine against a virus to the subject, wherein the virus is of a species that possesses a genome encoding the antigenic determinant of the non-replicating viral antigen included in said immunogenic composition. 97. The method according to any of clauses 1 to 76 and 91 to 96, the immunogenic composition according to any of clauses 77 to 83, 91 and 93 to 95, or the use according to any of clauses 84 to 91 and 93 to 96, where the subject is an animal. Petition 870250088147, dated 09 / 29 / 2025, pages 294 / 315 4 / 79 98. The immunogenic composition, according to clause 97, the method, according to clause 97 or the use, according to clause 97, in which the subject is a pig. 99. The immunogenic composition, according to clause 98, the method, according to clause 97 or 98, or the use, according to clause 97 or 98, where the subject is a piglet or a sow. 100. The method, according to any one of clauses 76 and 91 to 99, the immunogenic composition, according to any one of clauses 77 to 83, 91 and 93 to 99, or the use according to any one of clauses 84 to 91 and 93 to 99, wherein the immunogenic composition comprises 10 to 800 pg of said non-replicating viral antigen per dose. 101. The method, according to clause 100, the immunogenic composition according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 15 to 800 pg of said non-replicating viral antigen per dose. 102. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 30 to 800 pg of said non-replicating viral antigen per dose. 103. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 50 to 800 pg of said non-replicating viral antigen per dose. Petition 870250088147, dated 09 / 29 / 2025, pages 295 / 315 75 / 79 104. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 100 to 800 pg of said non-replicating viral antigen per dose. 105. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 150 to 800 pg of said non-replicating viral antigen per dose. 106. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 200 to 800 pg of said non-replicating viral antigen per dose. 107. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 250 to 800 pg of said non-replicating viral antigen per dose. 108. The method, according to clause 100, the immunogenic composition, according to clause 100, or the use, according to clause 100, wherein the immunogenic composition comprises 300 to 800 pg of said non-replicating viral antigen per dose. 109. The method, according to any one of clauses 1 to 76 and 91 to 108, the immunogenic composition, according to any one of clauses 77 to 83, 91 and 93 to 108, or the use according to any one of clauses 84 to 91 and 93 to 108, Petition 870250088147, dated 09 / 29 / 2025, pages 296 / 315 6 / 79 where the immunogenic composition comprises up to 800 pg of said non-replicating viral antigen per dose. 110. The method, according to clause 109, the immunogenic composition, according to clause 109, or the use, according to clause 109, wherein the immunogenic composition comprises up to 700 pg of said non-replicating viral antigen per dose. 111. The method, according to clause 109, the immunogenic composition, according to clause 109, or the use, according to clause 109, wherein the immunogenic composition comprises up to 600 pg of said non-replicating viral antigen per dose. 112. The method, according to clause 109, the immunogenic composition, according to clause 109, or the use, according to clause 109, wherein the immunogenic composition comprises up to 500 pg of said non-replicating viral antigen per dose. 113. The method, in accordance with clause 109, the immunogenic composition, in accordance with clause 109, or the use, in accordance with clause 109, wherein the immunogenic composition comprises up to 400 pg of said non-replicating viral antigen per dose. 114. The method, in accordance with clause 109, the immunogenic composition, in accordance with clause 109, or the use, in accordance with clause 109, wherein the immunogenic composition comprises up to 300 pg of said non-replicating viral antigen per dose. 115. A liquid antigen concentrate for dilution in drinking water or liquid foods, wherein 1 mL of Petition 870250088147, dated 09 / 29 / 2025, pages 297 / 315 77 / 79 referred concentrate comprises approximately 100 to 800 pg of non-replicating viral antigen. 116. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 150 to 800 pg of non-replicating viral antigen. 117. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 200 to 800 pg of non-replicating viral antigen. 118. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 250 to 800 pg of non-replicating viral antigen. 119. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 300 to 800 pg of non-replicating viral antigen. 120. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 400 to 800 pg of non-replicating viral antigen. 121. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 500 to 800 pg of non-replicating viral antigen. 122. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate Petition 870250088147, dated 09 / 29 / 2025, pages 298 / 315 78 / 79 comprises approximately 600 to 800 pg of non-replicating viral antigen. 123. The liquid antigen concentrate, according to clause 115, wherein 1 mL of said concentrate comprises approximately 700 to 800 pg of non-replicating viral antigen. 124. The antigen concentrate, in accordance with any of clauses 115 to 123, wherein said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 30, and / or wherein said non-replicating viral antigen is expressed by baculovirus. 125. A method for enabling self-immunization against a virus by a subject, comprising the step of diluting a liquid antigen concentrate comprising non-replicating viral antigen in the subject's drinking water. 126. Container containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added. 127. The container in accordance with clause 126, wherein said container is selected from the group consisting of bowl, vessel and barrel. 128. The container, in accordance with clause 126 or 127, where said container is located in the living environment of a subject to be vaccinated. 129. Kit for immunizing a subject, comprising - a liquid antigen concentrate comprising non-replicating viral antigen; and Petition 870250088147, dated 09 / 29 / 2025, pages 299 / 315 79 / 79 - Instructions for diluting the aforementioned liquid antigen concentrate in drinking water or in liquid foods to be consumed by the subject. 130. The method, according to clause 125, the container, according to any of clauses 126 to 128, or the kit, according to clause 129, wherein the said non-replicating viral antigen is a non-replicating viral antigen, as specified in any of clauses 13 to 30, and / or wherein the said non-replicating viral antigen is an expressed baculovirus. 131. The method, according to clause 125 or 130, the container, according to any of clauses 126 to 128 and 130, or the kit, according to clause 129 or 130, wherein the said liquid antigen concentrate is the liquid antigen concentrate according to any of clauses 115 to 124. 132. The method, according to any of clauses 125, 130 and 131, the container of clauses 128, 130 and 131, or the kit, according to any of clauses 129 to 131, wherein the said subject is a subject as specified in any of clauses 97 to 99. Petition 870250088147, dated 09 / 29 / 2025, pp. 300 / 315

Claims

1 / 10 CLAIMS 1. A method for - inducing an immune response in a subject and / or - reducing one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, the method being characterized in that it comprises the oral administration to the subject of an immunogenic composition comprising non-replicating viral antigen.

2. A method for inducing an immune response against PCV2 in a subject, characterized in that the method comprises the steps of: adding an immunogenic composition comprising a non-replicating PCV2 antigen to the subject's drinking water or liquid food, and allowing the subject to self-administer the immunogenic composition.

3. A method for reducing one or more clinical signs, viral load, and / or viremia caused by a viral infection in a subject, characterized in that the method comprises the steps of: adding an immunogenic composition comprising non-replicating viral antigen to the subject's drinking water or liquid food, and allowing the subject to self-administer the immunogenic composition.

4. Method for reducing one or more clinical signs, viral load and / or viremia caused by a PCV2 infection Petition 870250088147, dated 09 / 29 / 2025, page 302 / 315 2 / 10 in a subject, characterized in that the method comprises the steps of: adding an immunogenic composition comprising a non-replicating PCV2 antigen to the subject's drinking water or liquid food, and allowing the subject to self-administer the immunogenic composition.

5. Immunogenic composition characterized by the fact that it comprises non-replicating viral antigen for use in a method to - induce an immune response in a subject and / or - reduce one or more clinical signs, viral load and / or viremia caused by a viral infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject.

6. Immunogenic composition characterized in that it comprises a non-replicating PCV2 antigen for use in a method for - inducing an immune response against PCV2 in a subject and / or - reducing one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject, wherein the method comprises the oral administration of said immunogenic composition to said subject, 7. Method according to claim 1, or immunogenic composition for use according to claim 5, characterized in that said immune response is an immune response against a virus, wherein said virus is preferably a virus that is of the species that has a genome that encodes - the non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of the non-replicating viral antigen.

8. A method according to any one of claims 1, 3 and 7, or an immunogenic composition for use according to claim 5 or 7, characterized in that said virus is PCV2; and / or in that the immune response is an immune response against PCV2; and / or in that said method is a method for reducing one or more clinical signs, viral load and / or viremia caused by a PCV2 infection in a subject.

9. A method according to claim 1 or 3, or an immunogenic composition for use according to claim 5, characterized in that said viral infection is an infection by a virus, said virus being of a species having a genome that encodes - said non-replicating viral antigen, or - the amino acid sequence of the antigenic determinant of said non-replicating viral antigen.

10. Method, according to any one of claims 7 to 9, or immunogenic composition for use according to any one of claims 7 to 9, characterized in that the said antigenic determinant is a protein capable of forming a virus-like particle.

11. A method according to any one of claims 1 to 4 and 7 to 10, or an immunogenic composition for use according to any one of claims 5 to 10, characterized in that the immunogenic composition is free of replicating viral antigen.

12. A method according to any one of claims 1 to 4 and 7 to 11, or an immunogenic composition for use according to any one of claims 5 to 11, characterized in that the immunogenic composition consists of - said non-replicating viral antigen; and - one or more carriers acceptable for veterinary use, or in which the immunogenic composition consists of - said non-replicating viral antigen; and - one or more carriers acceptable for veterinary use; - and, optionally, at least one adjuvant and / or, optionally, at least one immunogenic substance other than said viral antigen.

13. Method, according to any one of claims 1 to 4 and 7 to 12, or immunogenic composition for use according to any one of claims 5 to 12, characterized in that the immunogenic composition additionally contains a gel composition, in particular a hydrogel composition, Petition 870250088147, dated 09 / 29 / 2025, p.305 / 315 5 / 10 and wherein, optionally, the gel composition comprises one or more flavoring agents, and wherein the flavoring agent(s) is / are preferably capable of attracting pigs, and / or wherein one or more flavoring agents are preferably selected from the group consisting of sucrose, glucose, sodium saccharin, sodium cyclamate, xylitol, perillartin, sucralose, D-tryptophan, aspartame, dihydrochalcones, artificial fruit flavoring (e.g., strawberry flavoring), plasma protein (e.g., spray-dried plasma protein), cheese and cheese-like flavorings, milk powder, chocolate and chocolate by-products.

14. A method according to any one of claims 1 to 4 and 7 to 13, or an immunogenic composition for use according to any one of claims 5 to 13, characterized in that said non-replicating viral antigen comprises or is a recombinant protein, and wherein the recombinant protein is preferably capable of forming a virus-like particle.

15. Method, according to any one of claims 1 to 4 and 7 to 14, or immunogenic composition for use according to any one of claims 5 to 14, characterized in that said non-replicating viral antigen is – a virus-like particle, in particular a virus-like particle comprising a recombinant protein. Petition 870250088147, dated 09 / 29 / 2025, pp. 306 / 315 6 / 10 16. Method according to claim 14 or 15, or immunogenic composition for use according to claim 14 or 15, characterized in that the recombinant protein is - a recombinant viral capsid protein, and / or - a recombinant circovirus capsid protein or a recombinant parvovirus capsid protein, and / or - a recombinant porcine circovirus (PCV) capsid protein or a recombinant porcine parvovirus (PPV) capsid protein, and / or - a recombinant ORF2 protein of porcine circovirus type 2 (PCV2), wherein said PCV2 ORF2 protein comprises or consists of an amino acid sequence with at least 90%, preferably at least 95%, more preferably at least 98%, even more preferably at least 99%, or in particular, 100% sequence identity with the sequence of SEQ ID NO:1 or SEQ ID NO:2; and / or where the aforementioned recombinant protein is a protein expressed by recombinant baculovirus.

17. Method, according to any one of claims 1 to 4 and 7 to 16, or immunogenic composition for use according to any one of claims 5 to 16, characterized in that the immunogenic composition comprises at least 10 pg of non-replicating viral antigen per dose, or at least 15 pg of non-replicating viral antigen per dose, or Petition 870250088147, dated 09 / 29 / 2025, p. 307 / 315 7 / 10 at least 30 pg of non-replicating viral antigen per dose, or at least 50 pg of non-replicating viral antigen per dose, or at least 100 pg of non-replicating viral antigen per dose, or at least 150 pg of non-replicating viral antigen per dose, or at least 200 pg of non-replicating viral antigen per dose, or at least 250 pg of non-replicating viral antigen per dose.

18. A method according to any one of claims 12 to 17, or an immunogenic composition for use according to any one of claims 12 to 17, characterized in that said one or more carriers acceptable for veterinary use are selected from the group consisting of solvents, dispersing media, coatings, stabilizing agents, diluents, preservatives, antibacterial and antifungal agents, isotonic agents, and adsorption retardants.

19. A method according to any one of claims 1, 2 and 7 to 18, or an immunogenic composition for use according to any one of claims 5 to 18, characterized in that said immune response is a protective immune response.

20. Method, according to any one of claims 1 and 7 to 19, or immunogenic composition for use according to any one of claims 5 to 19, characterized in that the immunogenic composition is administered orally to the subject.

21. A method according to any one of claims 1 to 4 and 7 to 20, or an immunogenic composition for use according to any one of claims 5 to 20, characterized in that the subject is an animal, or in that the subject is a pig, or in that the subject is a piglet or a sow.

22. Method, according to any one of claims 1 to 4 and 7 to 21, or immunogenic composition for use according to any one of claims 5 to 21, characterized in that the immunogenic composition comprises 10 to 800 µg of non-replicating viral antigen per dose.

23. Method, according to any one of claims 1 to 4 and 7 to 22, or immunogenic composition for use according to any one of claims 5 to 22, characterized in that the immunogenic composition comprises up to 800 µg of non-replicating viral antigen per dose.

24. Liquid antigen concentrate for dilution in drinking water or liquid foods, characterized in that 1 mL of said concentrate comprises about 100 to 800 µg of non-replicating viral antigen, preferably about 300 to 800 µg of non-replicating viral antigen.

25. Method for enabling self-immunization against a virus by a subject characterized in that Petition 870250088147, dated 09 / 29 / 2025, pp. 309 / 315 9 / 10 comprises the step of diluting a liquid antigen concentrate comprising non-replicating viral antigen in the subject's drinking water.

26. A container characterized by the fact that it contains potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added.

27. A container, according to claim 26, characterized in that said container is selected from the group consisting of - a bowl containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added, - a container containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added, and - a barrel containing potable water to which a liquid antigen concentrate comprising non-replicating viral antigen has been added; and / or in that said container is located in the housing environment of a subject to be immunized.

28. Kit for immunizing a subject, characterized by the fact that it comprises - a liquid antigen concentrate that includes non-replicating viral antigen; and - instructions for diluting said liquid antigen concentrate in drinking water or liquid food to be consumed by the subject.

29. Liquid antigen concentrate for dilution in drinking water, according to claim 24, method, of Petition 870250088147, dated 09 / 29 / 2025, pp. 310 / 315 10 / 10 according to claim 25, container, according to claim 26 or 27, or kit according to claim 28, characterized in that said non-replicating viral antigen is a non-replicating viral antigen, as defined in claim 14 or 15, and / or in that said antigen and non-replicating viral antigen comprise a recombinant protein, as defined in claim 16.

30. Method according to claim 25 or 29, container according to any one of claims 26, 27 and 29, or kit according to claim 28 or 29, characterized in that said liquid antigen concentrate comprising non-replicating virus antigen is the liquid antigen concentrate as defined in claim 24 or 29.

31. Method, according to any one of claims 25, 29 and 30, container, according to any one of claims 27, 29 and 30, or kit, according to any one of claims 28 to 30, characterized in that the subject is an animal, or in that the subject is a pig, or in that the subject is a piglet or a sow. Petition 870250088147, dated 09 / 29 / 2025, pp. 311 / 315

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