Antibodies for opioid therapy

Abstract

The present disclosure provides, inter alia, antibodies, pharmaceutical compositions containing the antibodies, and uses of the antibodies and pharmaceutical compositions for treating or preventing opioid overdose, for treating opioid use disorder, and for treating or preventing opioid-induced respiratory depression.

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims priority to U.S. Patent Application No. 63 / 111,699 (filed November 10, 2020, currently pending), the disclosure of which is incorporated in its entirety by reference.

[0002] Statement regarding government support This invention was made with government support under grant number DA046323, awarded by the National Institutes of Health. The government has certain rights to this invention.

[0003] References to “arrangement lists,” tables, or appendices to computer program listings submitted as ASCII files. The sequence listing described in file 2014_1PC_20211105_SeqListing was created on November 5, 2021, is 75,558 bytes in machine format IBM-PC, MS Windows operating system, and is incorporated herein by reference. [Background technology]

[0004] The continued rise in opioid abuse creates a pressing need for fast-acting and effective treatments to combat opioid addiction and overdose. In early August 2017, the opioid crisis was declared a national emergency in the United States due to the continuing increase in reported opioid overdose cases. The pathogenesis of the surging opioid-related deaths is multifactorial, most commonly involving the abuse of potent semi-synthetic and fully synthetic opioids, namely heroin and fentanyl, respectively. Fentanyl-based drugs are potent μ-opioid receptor agonists, and this pharmacological property is responsible for their analgesic, addictive, and potentially dangerous central nervous system (CNS) depressant effects. First discovered by Paul Janssen in 1960, fentanyl is a DEA Schedule II drug routinely used in clinical practice. Fentanyl can be administered intravenously for anesthesia, and also transdermally and transmucosally via patches and lozenges, respectively, to relieve pain in various scenarios (e.g., postoperative, cancer-related, and acute pain). However, fentanyl reflects the heroin abuse tendency profile, and intentional abuse of prescription fentanyl patches has been reported. Heroin abuse has remained a public health concern for decades, but more recently, fentanyl, with its enhanced potency, poses an even greater risk to unlawful opioid users.

[0005] The increasing misuse of opioids highlights the growing need for new and creative methods to treat and counteract their effects. Naloxone is effective in reversing heroin and prescription opioid overdoses, but appears to be less effective against fentanyl and carfentanil. Specifically, the high potency of fentanyl-class drugs, particularly carfentanil, has been reported to overwhelm the duration of action and therapeutic effect of naloxone at typical doses. Fentanyl is effective as an analgesic and anesthetic induction agent, but its respiratory depressant effects make it particularly dangerous when used illegally. The pharmacology of carfentanil is not well-characterized in humans, but it has similar properties to fentanyl, but with significantly increased potency and the potential to cause "re-narcotic effects," where subjects experience opioid addiction for extended periods after apparent recovery. Although this phenomenon has not been studied in humans, it is known to occur in large animals sedated with carfentanil, and to prevent re-narcotic effects, a naloxone dose 100 times greater than the carfentanil dose is required. In clinical practice, continuous or multiple doses of naloxone over time are necessary to maintain recovery from fentanyl toxicity and prevent possible re-narcotic effects. Nalmefene is another opioid antagonist that has shown increased efficacy and extended duration of action against fentanyl and carfentanil-induced respiratory depression compared to naloxone. While opioid antagonists are useful in counteracting opioid overdose, there is a need in the art for new drugs and new approaches to treat or prevent opioid overdose and to treat opioid use disorder. This disclosure relates to this purpose and other important purposes. [Overview of the Initiative]

[0006] This specification provides antibodies having high affinity and specificity to synthetic opioids such as fentanyl, carfentanyl, and their analogues. This disclosure provides antibodies comprising (i) a light chain variable region including CDR L1 as described in SEQ ID NO: 1, CDR L2 as described in SEQ ID NO: 2, and CDR L3 as described in SEQ ID NO: 3; and (ii) a heavy chain variable region including CDR H1 as described in SEQ ID NO: 4, CDR H2 as described in SEQ ID NO: 5, and CDR H3 as described in SEQ ID NO: 6. This disclosure provides a method for preventing opioid overdose, a method for treating opioid overdose, and a method for treating opioid use disorder by administering an effective amount of any of the antibodies described herein to a patient. These embodiments and other embodiments of this disclosure are provided in detail herein. [Brief explanation of the drawing]

[0007] [Figure 1] Figures 1A-1C show the efficacy and half-life measurements of monoclonal antibodies (mAbs) in monkeys. Figure 1A: Rhesus monkeys (n=3) were administered a dose of fentanyl IV followed by a dose of 8 mg / kg IV of either JBZ-1 or a control mAb. The effect on tail-retraction antinociceptivity was observed and expressed as the percentage of the maximum possible effect (MPE). Figure 1B: The cumulative dose of fentanyl ED50 was measured in the same monkeys at three time points after mAb injection. Figure 1C: Blood samples were collected from the monkeys and analyzed by ELISA to determine antibody concentrations at specified time points. [Figure 2] Figures 2A-2C show the pharmacokinetics of fentanyl in human mAb-treated mice. Anti-fentanyl mAbs bind to large amounts of the drug in the blood, reducing peripheral drug exposure to the brain. Figure 2A: Time course experiment of blood fentanyl levels in mice (n=4) injected with 30 mg / kg mAb 48 hours before IV 0.1 mg / kg fentanyl injection. Figure 2B: Area under the fentanyl curve derived from panel A data. Figure 2C: Blood fentanyl levels in mice treated with JBZ-1, JBZ-2, and P2B5 at 15 minutes and 3 hours. [Figure 3]Figures 3A-3D illustrate the in vivo mAb-mediated antagonism of carfentanil-induced antinociceptiveness. Figures 3A-3B: JBZ-1 treatment 24 hours prior to drug loading shifts the carfentanil dose-response curve significantly to the right in the tail-flick and hot-plate tests. Figure 3C: Comparison of fentanyl ED50 in mice treated with JBZ-1, JBZ-2, and P2B5 in the tail-flick antinociceptive assay, demonstrating the superiority of JBZ-2. Figure 3D: Comparison of the percentage of mice below the maximum possible effect cutoff in the hot-plate antinociceptive assay when treated with JBZ-1, JBZ-2, and JBZ-3, demonstrating the superiority of JBZ-2. [Figure 4] Figures 4A–4C provide an evaluation of JBZ-2, JBZ-3, JBZ-4, and P2B5 antibodies in fentanyl antinociception. Figure 4A: Antinociception was induced by intraperitoneal administration of mAb (45 mg / kg) to n=4 female Swiss Webster mice, followed by intraperitoneal fentanyl administration of 0.4 mg / kg 4 hours after mAb administration. Figure 4B: Antinociception was tracked for 15–115 minutes after fentanyl administration and expressed as an average. Figure 4C: Fentanyl antinociception was retested in the same mice 2 days after mAb administration. [Figure 5] Figures 5A and 5B show the quantitative analysis of antibodies and fentanyl in mouse peripheral blood. Figure 5A: Fentanyl IP loading (0.4 mg / kg) was administered to the same mice from the antinociceptivity study, and blood was collected 20 minutes after drug injection. The sample was made basic, combined with a deuterated internal standard, extracted with an organic solvent, and analyzed by LC-MS / MS using a standard curve to interpolate unknown concentrations. Figure 5B: Blood samples collected before drug administration and 2 days after mAb administration were analyzed by ELISA. [Figure 6] Figures 6A-6B show the rescue of fentanyl-induced antinociceptiveness by injecting JBZ-4 and JBZ-7. After administration of 0.2 mg / kg of fentanyl IP, mice were tested 15 minutes later using the hot plate assay (Figure 6A) and tail flick (Figure 6B) antinociceptiveness assays. Immediately afterward, 30 mg / kg of intravenous antibody was administered, and the tests were restarted. JBZ-4 was superior to JBZ-7. [Figure 7] Figures 7A-7B are diagrams showing that JBZ-4 blocks and rescues carfentanil-induced respiratory depression. Figure 7A: Mice pretreated with 30 mg / kg JBZ-4 were challenged with IV carfentanil (30 μg / kg) 48 hours later, and respiration was observed by whole body plethysmography and expressed as the minute ventilation volume (MV) normalized to the baseline. Figure 7B: In the rescue experiment, mice were administered IP carfentanil (30 μg / kg), followed by IV rescue doses of 1 mg / kg naloxone or (60 mg / kg) JBZ-4, and respiration was observed. [Figure 8] Figures 8A-8B are raw sensorgrams of the association rate (kon) and dissociation rate (koff) of fentanyl (Figure 8A) and carfentanil (Figure 8B) to JBZ-4 using an approximation curve. [Figure 9] It is a diagram showing the concentration-time profile of monoclonal antibody JBZ-4 in rats after a single intravenous bolus administration of JBZ-4 at 10, 100, and 250 mg / kg.

Mode for Carrying Out the Invention

[0008] Definitions The headings of the sections used in this specification are for purposes of organization only and are not to be construed as limiting the subject matter being described. All documents or portions of documents cited in this application, such as patents, patent applications, articles, books, manuals, and papers (not limited thereto), are hereby incorporated by reference in their entirety for all purposes.

[0009] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. For example, reference is made to Singleton et al., Dictionary of Microbiology and Molecular Biology, 2nd ed., J. Sambrook et al., Molecular Cloning, A Laboratory Manual, Cold Springs Harbor Press (Cold Springs Harbor, NY 1989). Methods, apparatus, and materials similar or equivalent to those described herein can be used in the practice of the present disclosure. The following definitions are provided to facilitate understanding of certain terms frequently used herein and are not meant to limit the scope of the present disclosure.

[0010] In the present disclosure, terms such as "comprises," "comprising," "containing," and "having" can have the meaning ascribed to them in the United States Patent Law and can mean "includes" and "including," etc. Similarly, "consisting essentially of" or "consists essentially" has the meaning defined in the United States Patent Law, and the term is open-ended and allows for more than what is recited as long as the basic or novel features of what is recited do not change, but excludes prior art embodiments.

[0011] As used herein, the term "about" means a range of values that would be reasonably considered by one of ordinary skill in the art to be similar to a particular value, including that particular value. In embodiments, the term "about" means within one standard deviation using measurements generally accepted in the art. In embodiments, "about" means a range extending from + / −10% of the specified value. In embodiments, "about" means the specified value.

[0012] "JBZ-1" refers to a monoclonal antibody having the light chain amino acid sequence described in SEQ ID NO: 45 and the heavy chain amino acid sequence described in SEQ ID NO: 46.

[0013] "JBZ-2" refers to a monoclonal antibody (mAb) having the light chain variable region described in SEQ ID NO: 37 and the heavy chain variable region described in SEQ ID NO: 23. In embodiments, the term refers to a monoclonal antibody (mAb) having the light chain amino acid sequence described in SEQ ID NO: 38 and the heavy chain amino acid sequence described in SEQ ID NO: 25.

[0014] "JBZ-3" refers to a JBZ-2 antibody that has six additional mutations in the heavy chain variable region (sequence not shown).

[0015] "JBZ-4" refers to an antibody having a light chain variable region containing CDR L1 described in SEQ ID NO: 1, CDR L2 described in SEQ ID NO: 2, and CDR L3 described in SEQ ID NO: 3; and a heavy chain variable region containing CDR H1 described in SEQ ID NO: 4 or SEQ ID NO: 15, CDR H2 described in SEQ ID NO: 5 or SEQ ID NO: 16, and CDR H3 described in SEQ ID NO: 6. In embodiments, the term refers to an antibody containing the light chain variable region described in SEQ ID NO: 20 and the heavy chain variable region described in SEQ ID NO: 23. In embodiments, the term refers to an antibody containing the light chain amino acid sequence described in SEQ ID NO: 22 and the heavy chain amino acid sequence described in SEQ ID NO: 25.

[0016] "JBZ-5" refers to an antibody containing the light chain variable region described in SEQ ID NO: 43 and the heavy chain variable region described in SEQ ID NO: 23. In embodiments, the term refers to an antibody containing the light chain amino acid sequence described in SEQ ID NO: 44 and the heavy chain amino acid sequence described in SEQ ID NO: 25.

[0017] "JBZ-6" refers to an antibody containing the light chain variable region described in SEQ ID NO: 40 and the heavy chain variable region described in SEQ ID NO: 23. In embodiments, the term refers to an antibody containing the light chain amino acid sequence described in SEQ ID NO: 41 and the heavy chain amino acid sequence described in SEQ ID NO: 25.

[0018] "JBZ-7" refers to a JBZ-4 antibody that has six additional mutations in the heavy chain variable region (sequence not shown).

[0019] The six comparative antibodies (sequences not shown) are referred to herein as "P1A2," "P2C1," "P2B5," "P1C1," "P1D8," and "P1F8."

[0020] "PBS" refers to phosphate-buffered saline.

[0021] Antibodies are large, complex molecules with intricate internal structures. Natural antibody molecules contain two identical polypeptide chain pairs, each having one light chain and one heavy chain. Each light and heavy chain then consists of two regions: a variable ("V") region involved in binding to the target antigen and a constant ("C") region that interacts with other components of the immune system. The light and heavy chain variable regions fold together in three-dimensional space to form a variable domain that binds to the antigen (e.g., drugs such as opioids or receptors on the cell surface). Within each light or heavy chain variable domain are three short segments (averaging 10 amino acids in length) called complementarity-determining regions ("CDRs"). The six CDRs of the antibody variable domain (three from the light chain and three from the heavy chain) fold together in three-dimensional space to form the actual antibody-binding site that docks to the target antigen (e.g., opioids). The portion of the variable domain not included in the CDRs is called the framework ("FR") and forms the environment for the CDRs. In embodiments, the positions of CDR and FR are defined herein by the Chothia numbering system (Chothia et al, J. Mol. Biol, 196(4):901-917(1987); Chothia et al, Nature, 342(6252: 877-883(1989); Al-Lazikani et al, J. Mol. Biol. 273(4):927-948(1997)). In embodiments, the positions occupied by individual residues within the light or heavy chain of the antibody are defined herein by the Chothia numbering system. In embodiments, the positions of CDR and FR are defined herein by the Kabat numbering system (Kabat et al., Sequences of Proteins of Immunological Interest, Fifth Edition, US Department of Health and Human Services, US Government Printing Office). (1991)). In embodiments, the positions occupied by individual residues within the light or heavy chain of the antibody are defined herein by the Kabat numbering system.Through this disclosure, the positions of residues required for binding within the light and heavy chains of an antibody are defined by the positions of the residues according to the Kabat numbering system or the Chothia numbering system, as is well known in the art.

[0022] The term "antibody" is used according to the meaning commonly known in the art. Antibodies exist, for example, as intact immunoglobulins or as a number of well-characterized fragments produced by digestion by various peptidases. For example, pepsin digests antibodies under disulfide linkages in the hinge region, and itself is formed by disulfide bonds. H -C H1 It produces F(ab)′2, a dimer of Fab, which is a light chain bound to Fab. Under mild conditions, F(ab)′2 can be reduced to cleave the disulfide linkage in the hinge region, thereby converting the F(ab)′2 dimer to a Fab′ monomer. The Fab′ monomer is essentially Fab with a portion of the hinge region (see Fundamental Immunology (Paul ed., 3d ed. 1993)). Various antibody fragments are defined in relation to the digestion of intact antibodies, but those skilled in the art will understand that such fragments can be newly synthesized chemically or by using recombinant DNA methods. Thus, the term antibody as used herein also includes antibody fragments produced by modification of the whole antibody, or antibody fragments newly synthesized using recombinant DNA methods (e.g., single-chain Fv), or antibody fragments identified using phage display libraries (e.g., McCafferty et al., Nature 348:552-554 (1990)).

[0023] As provided herein, “antibody variants” refer to polypeptides that can bind to an antigen and contain one or more structural domains of an antibody or a fragment thereof. Non-limiting examples of antibody variants include single-domain antibodies or nanobodies, afibodies (polypeptides smaller than monoclonal antibodies (e.g., about 6 kDA), that bind to antigens with high affinity and can mimic monoclonal antibodies), monospecificity Fab2, bispecificity Fab2, triplicity Fab3, monovalent IgG, scFv, bispecificity diabodies, triplicity triabodies, scFv-Fc, minibodies, IgNAR, V-NAR, hcIgG, VhH, or peptibodies. As provided herein, “nanobodies” or “single-domain antibodies” are commonly known in the art and refer to antibody fragments consisting of a single monomeric variable antibody domain. Like the whole antibody, it can selectively bind to a specific antigen. As provided herein, “peptibodies” refer to peptide portions (via covalent or noncovalent linkers) bound to the Fc domain of an antibody.

[0024] The terms “CDR L1,” “CDR L2,” and “CDR L3” as provided herein refer to the complementarity-determining regions (CDRs) 1, 2, and 3 of the variable light (L) chain of an antibody. In embodiments, the variable light chain provided herein includes CDR L1, CDR L2, and CDR L3 in the N-terminal to C-terminal direction. Similarly, the terms “CDR H1,” “CDR H2,” and “CDR H3” as provided herein refer to the complementarity-determining regions (CDRs) 1, 2, and 3 of the variable heavy (H) chain of an antibody. In embodiments, the variable heavy chain provided herein includes CDR H1, CDR H2, and CDR H3 in the N-terminal to C-terminal direction.

[0025] The terms “FR L1,” “FR L2,” “FR L3,” and “FR L4” as provided herein are used according to their common meanings in the art and refer to framework regions (FRs) 1, 2, 3, and 4 of the variable light (L) chain of an antibody. In embodiments, the variable light chain provided herein includes FR L1, FR L2, FR L3, and FR L4 in the direction from the N-terminus to the C-terminus. Similarly, the terms “FR H1,” “FR H2,” “FR H3,” and “FR H4” as provided herein are used according to their common meanings in the art and refer to framework regions (FRs) 1, 2, 3, and 4 of the variable heavy (H) chain of an antibody. In embodiments, the variable heavy chain provided herein includes FR H1, FR H2, FR H3, and FR H4 in the direction from the N-terminus to the C-terminus.

[0026] Exemplary immunoglobulin (antibody) structural units include tetramers. Each tetramer consists of two identical pairs of polypeptide chains, each pair having one “light” chain (approximately 25 kD) and one “heavy” chain (approximately 50–70 kD). The N-terminus of each chain defines a variable region of approximately 100–110 or more amino acids, primarily involved in antigen recognition. The terms variable light chain (VL), variable light chain (VL) domain or light chain variable region and variable heavy chain (VH), variable heavy chain (VH) domain or heavy chain variable region refer to these light and heavy chain regions, respectively. The terms variable light chain (VL), variable light chain (VL) domain and light chain variable region as used herein may be used interchangeably. The terms variable heavy chain (VH), variable heavy chain (VH) domain and heavy chain variable region as used herein may be used interchangeably. The Fc region (i.e., the fragment crystallizable region) is the "base" or "tail" of an immunoglobulin and typically consists of two heavy chains that contribute to two or three constant domains, depending on the antibody class. The Fc region binds to specific proteins, enabling each antibody to generate an appropriate immune response against a given antigen.

[0027] The antibodies described herein, for example, recombinant, monoclonal, or polyclonal antibodies, can be produced by any technique known in the art (see, for example, Kohler & Milstein, Nature 256:495-497 (1975); Kozbor et al., Immunology Today 4: 72 (1983); Cole et al., pp. 77-96 in Monoclonal Antibodies and Cancer Therapy, Alan R. Liss, Inc. (1985); Coligan, Current Protocols in Immunology (1991); Harlow & Lane, Antibodies, A Laboratory Manual (1988); and Goding, Monoclonal Antibodies: Principles and Practice (2nd ed. 1986)). The genes encoding the heavy and light chains of the subject's antibodies can be cloned from cells, and for example, the gene encoding a monoclonal antibody can be cloned from a hybridoma and used to produce recombinant monoclonal antibodies. Gene libraries encoding the heavy and light chains of monoclonal antibodies can also be created from hybridomas or plasma cells. Random combinations of heavy and light chain gene products generate a large pool of antibodies with different antigen specificities (see, e.g., Kuby, Immunology (3rd ed. 1997)). Techniques for producing single-chain or recombinant antibodies (U.S. Patent No. 4,946,778, U.S. Patent No. 4,816,567) can be adapted to produce antibodies.Furthermore, humanized antibodies or human antibodies can be expressed using transgenic mice or other organisms such as other mammals (e.g., U.S. Patents No. 5,545,807; 5,545,806; 5,569,825; 5,625,126; 5,633,425; 5,661,016; Marks et al., Bio / Technology 10:779-783 (1992); Lonberg et al., Nature 368:856-859 (1994); Morrison, Nature 368:812-13 (1994); Fishwild et al., Nature Biotechnology 14:845-51 (1996); Neuberger, Nature Biotechnology 14:826 (1996); and Lonberg & Huszar, Intern. Rev. Immunol. See 13:65-93 (1995). Alternatively, phage display technology can be used to identify antibodies and heteromer Fab fragments that specifically bind to selected antigens (see, e.g., McCafferty et al., Nature 348:552-554 (1990); Marks et al., Biotechnology 10:779-783 (1992)). Antibodies can also be made bispecific, i.e., they can recognize two different antigens (see, e.g., WO 93 / 08829, Traunecker et al., EMBO J. 10:3655-3659 (1991); and Suresh et al., Methods in Enzymology 121:210 (1986)). The antibody may also be a heteroconjugate, for example, two covalently linked antibodies, or an immunotoxin (see, for example, U.S. Patent No. 4,676,980, WO91 / 00360; WO92 / 200373; and EP03089).

[0028] Methods for humanizing or primating non-human antibodies are known in the art (e.g., U.S. Patents 4,816,567; 5,530,101; 5,859,205; 5,585,089; 5,693,761; 5,693,762; 5,777,085; 6,180,370; 6,210,671; and 6,329,511; WO87 / 02671; EP Patent Application 0173494; Jones et al. (1986) Nature 321:522; and Verhoyen et al. (1988) Science 239:1534). Further information on humanized antibodies can be found, for example, in Winter and Milstein (1991) Nature 349:293. Generally, humanized antibodies have one or more amino acid residues introduced from a non-human source. These non-human amino acid residues are often called import residues and are typically obtained from the import variable domain. Humanization can be carried out essentially by replacing the corresponding sequence of the human antibody with a rodent CDR or CDR sequence, following the method of Winter et al. (see, for example, U.S. Patents 4,816,567; 5,530,101; 5,859,205; 5,585,089; 5,693,761; 5,693,762; 5,777,085; 6,180,370; 6,210,671; and 6,329,511; WO 87 / 02671; EP Patent Application 0173494; Jones et al. (1986) Nature 321:522; and Verhoyen et al. (1988) Science 239:1534). Therefore, such humanized antibodies are chimeric antibodies (U.S. Patent No. 4,816,567), in which substantially less of the intact human variable domain is replaced by corresponding sequences from non-human species. In fact, humanized antibodies are typically human antibodies in which several CDR residues and possibly several FR residues are replaced by residues from similar sites in rodent antibodies.For example, a polynucleotide comprising a first sequence encoding a humanized immunoglobulin framework region and a second sequence set encoding a desired immunoglobulin complementarity-determining region can be produced synthetically or by combining appropriate cDNA and genomic DNA segments. Human constant region DNA sequences can be isolated from various human cells according to known procedures.

[0029] A "chimeric antibody" is an antibody molecule in which (a) the constant region or part thereof is modified, substituted, or exchanged so that the antigen-binding site (variable region) is linked to the constant region of a different antibody or a modified class, effector function and / or species, or to a completely different molecule that gives the chimeric antibody new properties, such as an enzyme, toxin, hormone, growth factor, drug, etc.; or (b) the variable region or part thereof is modified, substituted, or exchanged with a variable region having a different or modified antigen specificity. In embodiments, the antibodies described herein are humanized and / or chimeric monoclonal antibodies.

[0030] The epitope of an mAb is the region of its antigen to which the mAb binds. Two antibodies bind to the same or overlapping epitopes if each competitively inhibits (blocks) the binding of the other to the antigen. That is, a 1x, 5x, 10x, 20x, or 100x excess of one antibody inhibits the binding of the other antibody by at least 30%, preferably up to 50%, 75%, 90%, or 99%, as measured by a competitive binding assay (see, e.g., Junghans et al., Cancer Res. 50:1495, 1990). Alternatively, if essentially all amino acid mutations in the antigen that reduce or eliminate the binding of one antibody also reduce or eliminate the binding of the other, the two antibodies have the same epitope. If several amino acid mutations that reduce or eliminate the binding of one antibody also reduce or eliminate the binding of the other, the two antibodies have overlapping epitopes.

[0031] A single-stranded variable fragment (scFv) is typically a fusion protein of the variable regions of the heavy chain (VH) and light chain (VL) of an immunoglobulin, linked by a short linker peptide of approximately 10 to 25 amino acids. The linker is usually rich in glycine for flexibility and serine or threonine for solubility. The linker can connect the N-terminus of the VH to the C-terminus of the VL, or vice versa. In some embodiments, the linker contains multiple serine molecules. In some embodiments, the linker contains multiple glycine molecules. In some embodiments, the linker has a -(Gly-Gly-Gly-Gly-Ser)3- structure.

[0032] When referring to opioids, proteins, or peptides, the phrases "specifically (or selectively) bind" or "specifically (or selectively) immune to" an antibody often refer to the binding reaction that determines the presence of an opioid or protein in a heterogeneous group of opioids, proteins, and other biopharmaceuticals. Therefore, under specified immunoassay conditions, a particular antibody will bind to a specific opioid or protein at at least twice the background level, more typically 10 to over 100 times the background level. Specific binding to an antibody under such conditions requires an antibody selected for its specificity to a particular opioid or protein. For example, by selecting polyclonal antibodies, one can obtain only a subset of antibodies that specifically immune to a selected antigen and not to other proteins. This selection can be achieved by excluding antibodies that cross-react with other molecules. Various immunoassay formats can be used to select antibodies that specifically immune to a particular opioid or protein. For example, solid-phase ELISA immunoassays are routinely used to select antibodies that specifically react with proteins (for a description of immunoassay formats and conditions that can be used to determine specific immunoreactivity, see, for example, Harlow & Lane, Using Antibodies, A Laboratory Manual (1998)).

[0033] The term "amino acid" refers to natural and synthetic amino acids, as well as amino acid analogs and amino acid mimes that function in a similar manner to natural amino acids. Natural amino acids are those encoded by the genetic code, as well as those that are later modified, such as hydroxyproline, γ-carboxyglutamic acid, and O-phosphoserine. Amino acid analogs refer to compounds that have the same basic chemical structure as natural amino acids, i.e., hydrogen, a carboxyl group, an amino group, and an α-carbon bonded to an R group, such as homoserine, norleucine, methionine sulfoxide, and methionine methylsulfonium. Such analogs have a modified R group (e.g., norleucine) or a modified peptide backbone, but retain the same basic chemical structure as natural amino acids. Amino acid mimes refer to compounds that have a different structure from the general chemical structure of amino acids, but function in a similar manner to natural amino acids. The terms "non-naturally occurring amino acid" and "unnatural amino acid" refer to amino acid analogs, synthetic amino acids, and amino acid mimes that are not found in nature.

[0034] Amino acids may be referred to herein by either a commonly known three-letter symbol or a single-letter symbol recommended by the IUPAC-IUB Biochemical Nomenclature Committee. Similarly, nucleotides may be referred to by a commonly accepted single-letter code.

[0035] The terms “polypeptide,” “peptide,” and “protein” are used interchangeably herein to refer to polymers of amino acid residues, which may be bonded to non-amino acid portions. This term applies to amino acid polymers, in which one or more amino acid residues are artificial chemical mimics of corresponding natural amino acids, as well as to natural and non-natural amino acid polymers. A “fusion protein” refers to a chimeric protein that encodes two or more distinct protein sequences expressed by recombination as a single portion.

[0036] "Nucleic acid" refers to nucleotides (e.g., deoxyribonucleotides or ribonucleotides) and polymers thereof in single-stranded, double-stranded, or multi-stranded forms, or their complements or nucleosides (e.g., deoxyribonucleosides or ribonucleosides). In embodiments, "nucleic acid" does not include nucleosides. Terms such as "polynucleotide," "oligonucleotide," and "oligo" refer to linearly linked nucleotides in their usual and customary sense. The term "nucleoside" refers to glycosylamines containing a nucleic acid base and a pentose (ribose or deoxyribose) in their usual and customary sense. Non-limiting examples of nucleosides include cytidine, uridine, adenosine, guanosine, thymidine, and inosine. The term "nucleotide" refers to a single unit, i.e., monomer, of a polynucleotide in its usual and customary sense. A nucleotide can be a ribonucleotide, a deoxyribonucleotide, or a modified version thereof. Examples of polynucleotides intended herein include single-stranded and double-stranded DNA, single-stranded and double-stranded RNA, and hybrid molecules having mixtures of single-stranded and double-stranded DNA and RNA. Nucleic acids, for example, examples of polynucleotides intended herein include all types of RNA, e.g., mRNA, siRNA, miRNA, and guide RNA, and all types of DNA, genomic DNA, plasmid DNA, and minicircle DNA, and any fragments thereof. In the context of polynucleotides, the term “double-stranded” means double-stranded in the usual and customary sense. Nucleic acids can be linear or branched. For example, a nucleic acid can be a linear nucleotide, or a nucleic acid can be branched, for example, thereby a nucleic acid can contain one or more arms or branches of a nucleotide. Optionally, branched nucleic acids can repeatedly branch to form higher-order structures such as dendrimers.

[0037] As used herein, the term “complement” refers to a nucleotide (e.g., RNA or DNA) or nucleotide sequence that can base-pair with a complementary nucleotide or nucleotide sequence. As described herein and commonly known in the art, the complementary (identical) nucleotide of adenosine is thymidine, and the complementary (identical) nucleotide of guanosine is cytosine. Thus, a complement may include a sequence of nucleotides that base-pair with the corresponding complementary nucleotide of a second nucleic acid sequence. The nucleotides of the complement may partially or completely match the nucleotides of the second nucleic acid sequence. If the nucleotides of the complement completely match each nucleotide of the second nucleic acid sequence, the complement forms a base pair with each nucleotide of the second nucleic acid sequence. If the nucleotides of the complement partially match the nucleotides of the second nucleic acid sequence, only some of the nucleotides of the complement form a base pair with the nucleotides of the second nucleic acid sequence. Examples of complementary sequences include coding sequences and non-coding sequences, where the non-coding sequence includes nucleotides complementary to the coding sequence and thus forms the complement of the coding sequence. Further examples of complementary sequences are sense and antisense sequences, where the sense sequence contains nucleotides complementary to the antisense sequence, thus forming the complement of the antisense sequence.

[0038] As described herein, sequence complementarity can be partial, where only some nucleic acids match according to base pairing, or complete, where all nucleic acids match according to base pairing. Thus, two complementary sequences can have a certain percentage of identical nucleotides (i.e., about 60% identity in a given region, preferably 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or higher identity).

[0039] A polynucleotide typically consists of a specific sequence of four nucleotide bases: adenine (A); cytosine (C); guanine (G); and thymine (T) (or uracil (U) if the polynucleotide is RNA). Therefore, the term "polynucleotide sequence" is the alphabetical representation of a polynucleotide molecule; or, the term may apply to the polynucleotide molecule itself. This alphabetical representation can be entered into a database on a computer with a central processing unit and used in bioinformatics applications such as functional genomics and homology searches. A polynucleotide may optionally contain one or more non-standard nucleotides, nucleotide analogs, and / or modified nucleotides.

[0040] The term "conservatively modified variant" applies to both amino acid sequences and nucleic acid sequences. For a given nucleic acid sequence, a "conservatively modified variant" refers to a nucleic acid encoding the same or essentially the same amino acid sequence. Due to the degeneracy of the genetic code, many nucleic acid sequences encode any given protein. For example, the codons GCA, GCC, GCG, and GCU all encode the amino acid alanine. Therefore, at all positions where alanine is identified by the codon, the codon can be changed to any of the corresponding codons described without altering the encoded polypeptide. Such nucleic acid mutations are a type of conservatively modified mutation called "silent mutations." All nucleic acid sequences in this specification encoding polypeptides also describe all possible silent mutations of the nucleic acid. It will be apparent to those skilled in the art that by modifying each codon in a nucleic acid (except AUG, usually the sole codon for methionine, and TGG, usually the sole codon for tryptophan), functionally identical molecules can be obtained. Therefore, each silent mutation of a polypeptide-encoding nucleic acid is inherent in each sequence described.

[0041] Those skilled in the art will recognize that, with respect to amino acid sequences, individual substitutions, deletions, or additions to nucleic acids, peptides, polypeptides, or protein sequences that modify, add, or delete a single amino acid or a small proportion of amino acids in the encoded sequence are "conservatively modified variants," and that such modifications replace the amino acid with a chemically similar amino acid. Conservative substitution tables providing functionally similar amino acids are well known in the art. Such conservatively modified variants are added to, and not excluded from, the polymorphic variants, interspecific congeners, and alleles of this disclosure.

[0042] The following eight groups: (1) alanine (A), glycine (G); (2) aspartic acid (D), glutamic acid (E); (3) asparagine (N), glutamine (Q); (4) arginine (R), lysine (K); (5) isoleucine (I), leucine (L), methionine (M), valine (V); (6) phenylalanine (F), tyrosine (Y), tryptophan (W); (7) serine (S), threonine (T); and (8) cysteine ​​(C), methionine (M) contain amino acids that are conserved substitutions with each other.

[0043] The "percentage of sequence identity" is determined by comparing two optimally aligned sequences across a comparison window, where portions of the polynucleotide or polypeptide sequence within the comparison window may contain additions or deletions (i.e., gaps) compared to a reference sequence (which does not contain additions or deletions) for optimal alignment of the two sequences. The percentage is calculated by determining the number of positions where identical nucleic acid bases or amino acid residues occur in both sequences to obtain the number of matching positions, dividing the number of matching positions by the total number of positions in the comparison window, and multiplying the result by 100 to obtain the percentage of sequence identity.

[0044] In the context of two or more nucleic acid or polypeptide sequences, the terms “identical” or “percent “identical” refer to two or more sequences or subsequences that are identical or have a specified percentage of amino acid residues or nucleotides (i.e., 60% identity, arbitrarily 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or 99% identity) over a specified region of the entire polypeptide sequence or individual domains of the polypeptide sequence, when compared and aligned for maximum correspondence using a comparison window or one of the sequence comparison algorithms described below, or by manual alignment and macroscopic observation. Such sequences are said to be “substantially identical.” This definition also refers to the complementary strand of the test sequence. Optionally, identity exists over a region of at least about 50 nucleotides in length, or preferably over a region of 100 to 500 or 1000 or more nucleotides in length.

[0045] In sequence comparison, typically, one sequence acts as a reference sequence, and the test sequence is compared against it. When using a sequence comparison algorithm, the test sequence and reference sequence are input into the computer, subsequence coordinates are specified as needed, and sequence algorithm program parameters are specified. Default program parameters can be used, or different parameters can be specified. The sequence comparison algorithm then calculates the percentage sequence identity of the test sequence compared to the reference sequence based on the program parameters.

[0046] As used herein, “comparison window” includes, for example, a reference to the full sequence or to one of the number of adjacent positions selected from the group consisting of 20 to 600, about 50 to about 200, or about 100 to about 150 amino acids or nucleotides, in which case the sequence can be compared to a reference sequence with the same number of adjacent positions after the two sequences have been optimally aligned. Methods for aligning sequences for comparison are well known in the art. Optimal alignment of sequences for comparison can be performed, for example, by the local homology algorithm of Smith and Waterman (1970) Adv. Appl. Math. 2:482c, by the homology alignment algorithm of Needleman and Wunsch (1970) J. Mol. Biol. 48:443, by the similarity search of Pearson and Lipman (1988) Proc. Nat'l. Acad. Sci. USA 85:2444, by computerized implementations of these algorithms (GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr., Madison, WI), or by manual alignment and macroscopic inspection (see, for example, Ausubel et al., Current Protocols in Molecular Biology (1995 addendum)).

[0047] Examples of algorithms suitable for determining percent sequence identity and sequence similarity are the BLAST and BLAST2.0 algorithms described in Altschul et al. (1977) Nuc. Acids Res. 25:3389-3402 and Altschul et al. (1990) J. Mol. Biol. 215:403-410, respectively. Software for performing BLAST analysis is available through the National Center for Biotechnology Information (http: / / www.ncbi.nlm.nih.gov / ). This algorithm first identifies high-scoring sequence pairs (HSPs) by identifying short words of length W in the query sequence that match or satisfy a certain positive threshold score T when aligned with words of the same length in the database sequence. T is called the neighbor word score threshold (Altschul et al., above). These initial neighbor word hits serve as a seed to initiate a search for longer HSPs that contain them. Word hits are extended bidirectionally along each sequence as long as the cumulative alignment score increases. The cumulative score for nucleotide sequences is calculated using parameters M (reward score for matching residue pairs; always > 0) and N (penalty score for mismatched residues; always < 0). For amino acid sequences, the cumulative score is calculated using a scoring matrix. Extension of word hits in each direction is stopped when the cumulative alignment score decreases by X from its maximum achieved value; when the cumulative score becomes 0 or less due to the accumulation of 1 or more negative scoring residue alignments; or when the end of one of the sequences is reached. The BLAST algorithm parameters W, T, and X determine the sensitivity and speed of alignment. The BLASTN program (for nucleotide sequences) uses, by default, word length (W) 11, expected value (E) 10, M=5, N=-4, and comparison of both strands.For amino acid sequences, the BLASTP program defaults to using a word length (W) of 3, an expected value (E) of 10, and the BLOSUM62 scoring matrix (see, for example, Henikoff and Henikoff (1989) Proc. Natl. Acad. Sci. USA 89:10915), alignment (B) of 50, an expected value (E) of 10, M=5, N=-4, and a comparison of both strands.

[0048] The BLAST algorithm also performs a statistical analysis of the similarity between two sequences (see, for example, Karlin and Altschul (1993) Proc. Natl. Acad. Sci. USA 90:5873-5877). One measure of similarity provided by the BLAST algorithm is the smallest sum probability (P(N)), which provides an indicator of the probability that a match between two nucleotide or amino acid sequences would occur by chance. For example, if the smallest sum probability in a comparison between a test nucleic acid and a reference nucleic acid is less than approximately 0.2, less than approximately 0.01, or less than approximately 0.001, the nucleic acid is considered similar to the reference sequence.

[0049] An indicator that two nucleic acid sequences or polypeptides are substantially identical is that the polypeptide encoded by the first nucleic acid is immunologically cross-reactive with an antibody produced against the polypeptide encoded by the second nucleic acid, as described below. Therefore, a polypeptide is substantially identical to the second polypeptide, typically, for example, if the two peptides differ only by conservative substitutions. Another indicator that two nucleic acid sequences are substantially identical is that the two molecules or their complements hybridize with each other under stringent conditions, as described below. Yet another indicator that two nucleic acid sequences are substantially identical is that the sequences can be amplified using the same primers.

[0050] An amino acid residue in an antibody "corresponds" to a given residue if it occupies the same essential structural position as that residue within the antibody. For example, a selected residue in a comparative antibody corresponds to position 48 (according to the Kabat or Chothia numbering system) of the antibody provided herein if the selected residue occupies the same essential spatial or structural relationship to Kabat or Chothia position 48, as can be evaluated using methods applicable in the art. For example, a comparative antibody can be aligned to maximize sequence homology with the antibody provided herein, and the position of the aligned comparative antibody aligned with Kabat or Chothia position 48 can be determined to be its corresponding position. Alternatively, instead of (or in addition to) the primary sequence alignment described above, three-dimensional structural alignment can be used, for example, by aligning the structure of the comparative antibody to maximize correspondence with the antibody provided herein and the overall structure being compared. In this case, an amino acid occupying the same essential position as Kabat or Chothia position 48 in the structural model can be said to correspond.

[0051] The term "isolated," when applied to a protein, means that the protein, in its natural state, essentially does not contain other related cellular components. It may be either a dehydrated solution or an aqueous solution, but preferably in a homogeneous state. Purity and homogeneity are typically measured using analytical chemistry techniques such as polyacrylamide gel electrophoresis or high-performance liquid chromatography. The protein, which is the dominant chemical species present in the preparation, is substantially purified. The term "purified" means that the protein essentially produces a single band on the electrophoretic gel. In particular, it means that the protein is at least 85% pure, at least 90% pure, at least 95% pure, or at least 99% pure.

[0052] As used herein, the term “vector” refers to a nucleic acid molecule capable of transporting another nucleic acid to which it is ligated. One type of vector is a “plasmid,” which refers to a linear or circular double-stranded DNA loop to which additional DNA segments can be ligated. Another type of vector is a viral vector, which can to which additional DNA segments can be ligated to a viral genome. Certain vectors can self-replicate within the host cell into which they are introduced (e.g., bacterial vectors with bacterial origins of replication and episomal mammalian vectors). Other vectors (e.g., non-episomal mammalian vectors) are integrated into the host cell's genome upon introduction into the host cell and thereby replicate together with the host genome. Furthermore, certain vectors can direct the expression of a gene to which they are operably ligated. Such vectors are referred to herein as “expression vectors.” Generally, expression vectors useful in recombinant DNA technology are often in the form of plasmids. In this specification, “plasmid” and “vector” can be used interchangeably, as plasmids are the most commonly used form of vector. However, this disclosure is intended to include other forms of expression vectors, such as viral vectors that perform equivalent functions (e.g., replication-deficient retroviruses, adenoviruses, and adeno-associated viruses). Furthermore, some viral vectors can specifically or nonspecifically target certain cell types. A non-replicating or replication-deficient viral vector is a viral vector that can infect target cells and deliver a viral payload, but cannot continue the typical lytic pathway that leads to cell lysis and cell death.

[0053] As used herein, the terms “opioid” and “synthetic opioid” refer to fentanyl, fentanyl analogs, carfentanyl, and carfentanyl analogs.

[0054] "Fentanyl analogs" refer to analogs of fentanyl. In this context, fentanyl analogs are compounds that exhibit greater mu-opioid receptor binding than fentanyl, or compounds that exhibit mu-opioid receptor binding at approximately 0-50% less than fentanyl, approximately 0-25% less than fentanyl, or approximately 0-10% less than fentanyl, based on a standard in vitro or in vivo mu-opioid receptor binding assay (e.g., Lipinski et al., Molecules, 24(4):740(2019)). Exemplary fentanyl analogs include acetylfentanyl, alfentanyl, butylfentanyl, butylfentanyl, para-tolylfentanyl, 3-methylfentanyl, α-methylfentanyl, remifentanil, mefentanil, phenarizine, omefentanil, and milfentanil. In one embodiment, the fentanyl analog is acetylfentanyl, alfentanyl, butylfentanyl, para-tolylfentanyl, 3-methylfentanyl, α-methylfentanyl, or remifentanyl. In one embodiment, the fentanyl analog is acetylfentanyl. In one embodiment, the fentanyl analog is butylfentanyl. In one embodiment, the fentanyl analog is alfentanyl. In one embodiment, the fentanyl analog is remifentanyl. In one embodiment, the fentanyl analog is butylfentanyl. In one embodiment, the fentanyl analog is para-tolylfentanyl. In one embodiment, the fentanyl analog is 3-methylfentanyl. In one embodiment, the fentanyl analog is α-methylfentanyl. In one embodiment, the fentanyl analog is mefentanyl. In one embodiment, the fentanyl analog is phenaridine. In one embodiment, the fentanyl analog is omefentanyl. In this embodiment, the fentanyl analog is milfentanil.

[0055] "Carfentanil analogues" refers to analogues of carfentanil. In this embodiment, carfentanil analogues are compounds that exhibit greater mu-opioid receptor binding than carfentanil, or compounds that exhibit mu-opioid receptor binding at approximately 0-50% less than carfentanil, approximately 0-25% less than carfentanil, or approximately 0-10% less than carfentanil, based on a standard in vitro or in vivo mu-opioid receptor binding assay (e.g., Lipinski et al., Molecules, 24(4):740(2019)). Exemplary carfentanil analogues include sufentanil, remifentanil, alfentanil, lofentanil, brifentanil, and trefentanil. In this embodiment, the carfentanil analogue is sufentanil. In this embodiment, the carfentanil analogue is remifentanil. In one embodiment, the carfentanil analog is alfentanil. In another embodiment, the carfentanil analog is lofentanil. In another embodiment, the carfentanil analog is brifentanil. In another embodiment, the carfentanil analog is trefentanil.

[0056] antibody In this specification, (i) CDR L1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 1; CDR L2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 2; and CDR having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 3 The provided antibody includes a light chain variable region containing L3; and a heavy chain variable region containing (ii) CDR H1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 4; CDR H2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 5; and CDR H3 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody further comprises LFR1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 8, sequence The light chain framework region includes LFR3 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 9, and LFR4 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 10.In this embodiment, the antibody further comprises HFR1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 11; HFR2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 12, The heavy chain framework region includes HFR3 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 13, and HFR4 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 14. In embodiments, sequence numbers 1 to 14 are based on the Kabat numbering system. In embodiments, the antibody has a binding affinity to fentanyl that is greater than or equal to the binding affinity to fentanyl of an antibody having the light chain sequence of sequence number 22 and the heavy chain sequence of sequence number 25. In one embodiment, the antibody has a binding affinity to fentanyl that is 0% to 25% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 20% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 15% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In this embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25.In one embodiment, the antibody is an IgG antibody. In another embodiment, the antibody is an IgG1 antibody. In another embodiment, the antibody is a Fab' fragment. In another embodiment, the antibody is a F(ab)'2 fragment. In another embodiment, the antibody is scFv. In another embodiment, the antibody is a humanized antibody. In another embodiment, the antibody is a chimeric antibody. In another embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0057] This specification provides an antibody comprising (i) a light chain variable region having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 1, CDR L1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region having a CDR H1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 6. In one embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 6. In this embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 6.In this embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 6. In this embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In the embodiment, the antibody is a Fab' fragment. In the embodiment, the antibody is an F(ab)'2 fragment. In the embodiment, the antibody is scFv. In the embodiment, the antibody is a humanized antibody.In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0058] In one embodiment, the antibody further includes a light chain framework region comprising LFR1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 10. In another embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 11; HFR2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 12, HFR3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 13, and HFR4 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 14. In one embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 6. In another embodiment, the antibody further comprises a light chain framework region comprising LFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 10.In an embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 11; HFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 12; HFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 13; and HFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 14. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is an F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In an embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0059] This specification provides an antibody comprising (i) a light chain variable region including CDR L1 having the variant described in SEQ ID NO: 1 and one or more conservatively modified variants; CDR L2 having the variant described in SEQ ID NO: 2 and one or more conservatively modified variants; and CDR L3 having the variant described in SEQ ID NO: 3 and one or more conservatively modified variants; and (ii) a heavy chain variable region including CDR H1 having the variant described in SEQ ID NO: 4 and one or more conservatively modified variants; CDR H2 having the variant described in SEQ ID NO: 5 and one or more conservatively modified variants; and CDR H3 having the variant described in SEQ ID NO: 6 and one or more conservatively modified variants. In embodiments, the antibody further comprises a light chain framework region including LFR1 having the variant described in SEQ ID NO: 7 and one or more conservatively modified variants; LFR2 having the variant described in SEQ ID NO: 8 and one or more conservatively modified variants; LFR3 having the variant described in SEQ ID NO: 9 and one or more conservatively modified variants; and LFR4 having the variant described in SEQ ID NO: 10 and one or more conservatively modified variants. In the embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having the variant described in SEQ ID NO: 11 and one or more conservatively modified variants; HFR2 having the variant described in SEQ ID NO: 12 and one or more conservatively modified variants; HFR3 having the variant described in SEQ ID NO: 13 and one or more conservatively modified variants; and HFR4 having the variant described in SEQ ID NO: 14 and one or more conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from 1 to about 10 conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from 1 to about 9 conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from 1 to about 8 conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from 1 to about 7 conservatively modified variants.In one embodiment, one or more conservatively modified variants are independently selected from one to about six conservatively modified variants. In another embodiment, one or more conservatively modified variants are independently selected from one to about five conservatively modified variants. In yet another embodiment, one or more conservatively modified variants are independently selected from one to about four conservatively modified variants. In yet another embodiment, one or more conservatively modified variants are independently selected from one to about three conservatively modified variants. In yet another embodiment, one or more conservatively modified variants are independently selected from one or two conservatively modified variants. In yet another embodiment, one or more conservatively modified variants are one conservatively modified variant. In yet another embodiment, one or more conservatively modified variants are two conservatively modified variants. In yet another embodiment, one or more conservatively modified variants are three conservatively modified variants. In one embodiment, one or more conservatively modified variants are four conservatively modified variants. In another embodiment, one or more conservatively modified variants are five conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In one embodiment, a conservatively modified mutation is a conservative substitution. In another embodiment, a conservatively modified mutation is an amino acid deletion. In another embodiment, a conservatively modified mutation is an amino acid addition. In yet another embodiment, the antibody has a fentanyl binding affinity that is greater than or equal to the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a fentanyl binding affinity that is 0% to 25% less than the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25.In one embodiment, the antibody has a binding affinity to fentanyl that is 0% to 20% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 15% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody is an IgG antibody. In yet another embodiment, the antibody is an IgG1 antibody. In yet another embodiment, the antibody is a Fab' fragment. In one embodiment, the antibody is an F(ab)'2 fragment. In another embodiment, the antibody is scFv. In another embodiment, the antibody is a humanized antibody. In another embodiment, the antibody is a chimeric antibody. In another embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0060] This specification provides an antibody comprising (i) a light chain variable region including CDR L1 as described in SEQ ID NO: 1, CDR L2 as described in SEQ ID NO: 2, and CDR L3 as described in SEQ ID NO: 3; and (ii) a heavy chain variable region including CDR H1 as described in SEQ ID NO: 4, CDR H2 as described in SEQ ID NO: 5, and CDR H3 as described in SEQ ID NO: 6. In an embodiment, the antibody further comprises a light chain framework region including LFR1 as described in SEQ ID NO: 7, LFR2 as described in SEQ ID NO: 8, LFR3 as described in SEQ ID NO: 9, and LFR4 as described in SEQ ID NO: 10. In an embodiment, the antibody further comprises a heavy chain framework region including HFR1 as described in SEQ ID NO: 11; HFR2 as described in SEQ ID NO: 12, HFR3 as described in SEQ ID NO: 13, and HFR4 as described in SEQ ID NO: 14. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is an F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0061] In this specification, (i) CDR L1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 1; CDR L2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 2; and CDR having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 3 An antibody is provided which includes a light chain variable region containing L3; and a heavy chain variable region containing (ii) a CDR H1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 15; a CDR H2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 16; and a CDR H3 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody further comprises LFR1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 8, sequence The light chain framework region includes LFR3 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 9, and LFR4 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 10.In this embodiment, the antibody further comprises HFR1 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 17; HFR2 having an amino acid sequence having at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with SEQ ID NO: 18, The heavy chain framework region includes HFR3 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 19, and HFR4 having an amino acid sequence with at least 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with sequence number 14. In embodiments, sequences 1-3, 6-10, 14-16, and 17-19 are based on the Chothia numbering system. In embodiments, the antibody has a binding affinity to fentanyl that is greater than or equal to the binding affinity to fentanyl of an antibody having the light chain sequence of sequence number 22 and the heavy chain sequence of sequence number 25. In one embodiment, the antibody has a binding affinity to fentanyl that is 0% to 25% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 20% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 15% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25.In the embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In the embodiment, the binding affinity is determined by the assay described in Example 3. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In the embodiment, the antibody is a Fab' fragment. In the embodiment, the antibody is a F(ab)'2 fragment. In the embodiment, the antibody is scFv. In the embodiment, the antibody is a humanized antibody. In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0062] This specification provides an antibody comprising (i) a light chain variable region having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 1, CDR L1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region having a CDR H1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 6. In one embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 92% sequence identity with SEQ ID NO: 6. In this embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 6.In one embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 6. In this embodiment, the antibody includes (i) a light chain variable region comprising CDR L1 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody includes (i) a light chain variable region having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 1, CDR L1 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 3; and (ii) a heavy chain variable region having CDR H1 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 6. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In the embodiment, the antibody is a Fab' fragment. In the embodiment, the antibody is an F(ab)'2 fragment. In the embodiment, the antibody is scFv. In the embodiment, the antibody is a humanized antibody.In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0063] In one embodiment, the antibody further includes a light chain framework region comprising LFR1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 10. In another embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 17; HFR2 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 18, HFR3 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 19, and HFR4 having an amino acid sequence having at least 90% sequence identity with SEQ ID NO: 14. In one embodiment, the antibody further includes a light chain framework region comprising LFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 10. In another embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 17; HFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 18, HFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 19, and HFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 14. In another embodiment, the antibody is an IgG antibody. In yet another embodiment, the antibody is an IgG1 antibody. In yet another embodiment, the antibody is a Fab' fragment. In yet another embodiment, the antibody is an F(ab)'2 fragment. In yet another embodiment, the antibody is scFv. In yet another embodiment, the antibody is a humanized antibody. In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids that can encode the antibodies described herein, including all embodiments.This specification provides vectors comprising nucleic acids capable of encoding antibodies described herein, including all embodiments.

[0064] This specification provides an antibody comprising (i) a light chain variable region including CDR L1 having the variant described in SEQ ID NO: 1 and one or more conservatively modified variants; CDR L2 having the variant described in SEQ ID NO: 2 and one or more conservatively modified variants; and CDR L3 having the variant described in SEQ ID NO: 3 and one or more conservatively modified variants; and (ii) a heavy chain variable region including CDR H1 having the variant described in SEQ ID NO: 15 and one or more conservatively modified variants; CDR H2 having the variant described in SEQ ID NO: 16 and one or more conservatively modified variants; and CDR H3 having the variant described in SEQ ID NO: 6 and one or more conservatively modified variants. In embodiments, the antibody further comprises a light chain framework region including LFR1 having the variant described in SEQ ID NO: 7 and one or more conservatively modified variants; LFR2 having the variant described in SEQ ID NO: 8 and one or more conservatively modified variants; LFR3 having the variant described in SEQ ID NO: 9 and one or more conservatively modified variants; and LFR4 having the variant described in SEQ ID NO: 10 and one or more conservatively modified variants. In the embodiment, the antibody further includes a heavy chain framework region comprising HFR1 having the variant described in SEQ ID NO: 17 and one or more conservatively modified variants; HFR2 having the variant described in SEQ ID NO: 18 and one or more conservatively modified variants; HFR3 having the variant described in SEQ ID NO: 19 and one or more conservatively modified variants; and HFR4 having the variant described in SEQ ID NO: 14 and one or more conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from one to about five conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from one to about four conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from one to about three conservatively modified variants. In the embodiment, the one or more conservatively modified variants are independently selected from one or two conservatively modified variants. In the embodiment, the one or more conservatively modified variants is one conservatively modified variant.In the embodiment, one or more conservatively modified variants are two conservatively modified variants. In the embodiment, one or more conservatively modified variants are three conservatively modified variants. In the embodiment, one or more conservatively modified variants are four conservatively modified variants. In the embodiment, one or more conservatively modified variants are five conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In the embodiment, a conservatively modified mutation is a conservative substitution. In the embodiment, a conservatively modified mutation is an amino acid deletion. In the embodiment, a conservatively modified mutation is an amino acid addition. In the embodiment, the antibody has a binding affinity to fentanyl that is equal to or greater than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In one embodiment, the antibody has a binding affinity to fentanyl that is 0% to 25% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 20% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 15% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In the embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In the embodiment, the binding affinity is determined by the assay described in Example 3. In the embodiment, the antibody is an IgG antibody.In one embodiment, the antibody is an IgG1 antibody. In another embodiment, the antibody is a Fab' fragment. In another embodiment, the antibody is a F(ab)'2 fragment. In another embodiment, the antibody is scFv. In another embodiment, the antibody is a humanized antibody. In another embodiment, the antibody is a chimeric antibody. In another embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0065] This specification provides an antibody comprising (i) a light chain variable region including CDR L1 as described in SEQ ID NO: 1, CDR L2 as described in SEQ ID NO: 2, and CDR L3 as described in SEQ ID NO: 3; and (ii) a heavy chain variable region including CDR H1 as described in SEQ ID NO: 15, CDR H2 as described in SEQ ID NO: 16, and CDR H3 as described in SEQ ID NO: 6. In an embodiment, the antibody further comprises a light chain framework region including LFR1 as described in SEQ ID NO: 7, LFR2 as described in SEQ ID NO: 8, LFR3 as described in SEQ ID NO: 9, and LFR4 as described in SEQ ID NO: 10. In an embodiment, the antibody further comprises a heavy chain framework region including HFR1 as described in SEQ ID NO: 17; HFR2 as described in SEQ ID NO: 18, HFR3 as described in SEQ ID NO: 19, and HFR4 as described in SEQ ID NO: 14. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is an F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0066] This specification provides antibodies comprising (i) a light chain variable region including CDR L1 having the sequence xSxGxDxTxLxPxKxRxSxGxYx, CDR L2 having the sequence xKxDxTxExRxPxSx, and CDR L3 having the sequence xQxSxAxDxSxSxFxTxYxPxSx; and (ii) an antibody comprising a heavy chain variable region including CDR H1 having the sequence xSxRxNxWxWxSx or xGxGxFxIxSxSxRxNx, CDR H2 having the sequence xExVxYxHxTxGxIxTxNxYxNxPxSxLxKxSx or xYxHxTxGxIx, and CDR H3 having the sequence xExVxVxGxPxTxTxGxYxFxDxLx; where "x" is an amino acid or absent. In the embodiment, the antibody further comprises a light chain framework region including LFR1 having the sequence xSxYxExLxTxQxPxPxSxVxSxVxSxPxGxQxTxAxRxIxTxCx, LFR2 having the sequence xWxYxQxQxKxPxDxQxAxPxLxLxVxIxNx, LFR3 having the sequence xGxIxPxExRxFxSxGxSxKxSxGxTxTxVxTxLxTxIxSxGxVxQxAxExDxExAxDxYxYxCx, and LFR4 having the sequence xFxGxGxGxTxKxLxTxVxLx; where "x" is an amino acid or absent.In the application, the antibody further comprises HFR1 having the sequence xQxVxQxLxQxExSxGxPxGxLxVxKxPxSxGxTxLxSxLxTxCxTxVxSxGxGxFxIxSx or xQxVxQxLxQxExSxGxPxGxLxVxKxPxSxGxTxLxSxLxTxCxTxVxSx; HFR2 having the sequence xWxVxRxQxPxPxGxKxGxLxExWxIxGxExVx, and sequence xR The heavy chain framework region includes HFR3 having the sequence xVxTxIxSxVxDxKxSxKxNxQxFxSxLxKxLxSxSxVxTxAxAxDxTxAxVxYxYxCxAxRx or xTxNxYxNxPxSxLxKxSxRxVxTxIxSxVxDxKxSxKxNxQxFxSxLxKxLxSxSxVxTxAxAxDxTxAxVxYxYxCxAxRx, and HFR4 having the sequence xWxGxRxGxTxLxVxTxIxSxSx; where "x" is an amino acid or absent. In the embodiment, the antibody has a binding affinity to fentanyl that is greater than or equal to the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In one embodiment, the antibody has a binding affinity to fentanyl that is 0% to 25% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 20% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 15% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In yet another embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25.In the embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In the embodiment, the binding affinity is determined by the assay described in Example 3. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In the embodiment, the antibody is a Fab' fragment. In the embodiment, the antibody is a F(ab)'2 fragment. In the embodiment, the antibody is scFv. In the embodiment, the antibody is a humanized antibody. In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0067] This specification provides antibodies comprising a light chain variable region including (i) CDR L1 as described in SEQ ID NO: 1; (ii) CDR L2 as described in SEQ ID NO: 2; and (iii) CDR L3 as described in SEQ ID NO: 3, CDR L3 having the sequence xQSAxFTYPx; or CDR L3 having the sequence xQSADSSFTYPSx; and (iv) CDR H1 as described in SEQ ID NO: 4, CDR H1 as described in SEQ ID NO: 15, or CDR H1 having the sequence GGFISSRNW; (v) CDR H2 as described in SEQ ID NO: 5, CDR H2 as described in SEQ ID NO: 16, CDR H2 having the sequence xWxExIxNx; or CDR H2 having the sequence xWxExITNx; and (vi) a heavy chain variable region including CDR H3 as described in SEQ ID NO: 6, CDR H3 having the sequence xExVxGYFx; or CDR H3 having the sequence xExVGPxTGYFx; where x is independently absent or 1 to 8 amino acids. In embodiments, CDR L3 has the amino acid sequence of SEQ ID NO: 3. In the embodiment, CDR L3 has the sequence xQSAxFTYPx. In the embodiment, CDR L3 has the sequence xQSADSSFTYPSx. In the embodiment, CDR H1 is as described in SEQ ID NO: 4. In the embodiment, CDR H1 has the sequence GGFISSRNW. In the embodiment, CDR H1 is as described in SEQ ID NO: 15. In the embodiment, CDR H2 is as described in SEQ ID NO: 5. In the embodiment, CDR H2 is as described in SEQ ID NO: 16. In the embodiment, CDR H2 has the sequence xWxExIxNx. In the embodiment, CDR H2 has the sequence xWxExITNx. In the embodiment, CDR H3 is as described in SEQ ID NO: 6. In the embodiment, CDR H3 has the sequence xExVxGYFx. In the embodiment, CDR H3 has the sequence ExVGPxTGYFx. In the embodiment, x is independently absent or 1 to 7 amino acids. In the embodiment, x is independently absent or 1 to 6 amino acids. In the embodiment, x is independently absent or 1 to 5 amino acids. In the embodiment, x is independently absent or 1 to 4 amino acids. In the embodiment, x is independently absent or 1 to 3 amino acids. In the embodiment, x is independently absent or 1 to 2 amino acids.In the embodiments, x is independently absent or one amino acid. In the embodiments, the antibody is an IgG antibody. In the embodiments, the antibody is an IgG1 antibody. In the embodiments, the antibody is a Fab' fragment. In the embodiments, the antibody is a F(ab)'2 fragment. In the embodiments, the antibody is scFv. In the embodiments, the antibody is a humanized antibody. In the embodiments, the antibody is a chimeric antibody. In the embodiments, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0068] This specification includes (i) CDR L1 as described in SEQ ID NO: 1; (ii) CDR L2 as described in SEQ ID NO: 2; and (iii) CDR L3 as described in SEQ ID NO: 3, CDR L3 having sequence QSADSSFTYP; CDR L3 having sequence QSA; CDR L3 having sequence QSAD; CDR L3 having sequence QSADS; CDR L3 having sequence QSADSS; CDR L3 having sequence FTYP; CDR L3 having sequence SFTYP; CDR L3 having sequence SSFTYP; or CDR L3 having sequence DSSFTYP; and (iv) CDR H1 as described in SEQ ID NO: 4, CDR H1 as described in SEQ ID NO: 15, or CDR H1 having sequence GGFISSRNW; (v) CDR H2 as described in SEQ ID NO: 5, CDR H2 as described in SEQ ID NO: 16, CDR H2 having sequence WIGEVYHTGI, CDR H2 having sequence EVYHTGI, CDR H2 having sequence WIGEVYHTGITN, and CDR H2 having sequence WIGEVYHTGIT The provided antibody includes a heavy chain variable region comprising H2, CDR H2 having the sequence EVYHTGITN, CDR H2 having the sequence YHTGITN, CDR H2 having the sequence ITN; and (vi) CDR H3 as described in Sequence ID No. 6, CDR H3 having the sequence EVV, CDR H3 having the sequence EVVG, CDR H3 having the sequence EVVGP, CDR H3 having the sequence EVVGPT, CDR H3 having the sequence EVVGPTT, CDR H3 having the sequence EVVGPTTG, CDR H3 having the sequence EVVGPTTGY, CDR H3 having the sequence VGP, CDR H3 having the sequence GYF, CDR H3 having the sequence TGYF, CDR H3 having the sequence TTGYF, CDR H3 having the sequence PTTGYF, CDR H3 having the sequence GPTTGYF, CDR H3 having the sequence VGPTTGYF, or CDR H3 having the sequence EVVGPTTGYF. In the embodiment, CDR L3 has the amino acid sequence QSADSSFTYP. In one embodiment, CDR L3 has the amino acid sequence QSA. In another embodiment, CDR L3 has the amino acid sequence QSAD. In another embodiment, CDR L3 has the amino acid sequence QSADS. In yet another embodiment, CDR L3 has the amino acid sequence QSADSS.In an embodiment, CDR L3 has the amino acid sequence FTYP. In an embodiment, CDR L3 has the amino acid sequence SFTYP. In an embodiment, CDR L3 has the amino acid sequence SSFTYP. In an embodiment, CDR L3 has the amino acid sequence DSSFTYP. In an embodiment, CDR L3 has the amino acid sequence of SEQ ID NO: 3. In an embodiment, CDR H1 is as described in SEQ ID NO: 4. In an embodiment, CDR H1 is as described in SEQ ID NO: 15. In an embodiment, CDR H1 has the sequence GGFISSRNW. In an embodiment, CDR H2 has the sequence WIGEVYHTGI. In an embodiment, CDR H2 has the sequence EVYHTGI. In an embodiment, CDR H2 has the sequence WIGEVYHTGITN. In an embodiment, CDR H2 has the sequence WIGEVYHTGIT. In an embodiment, CDR H2 has the sequence EVYHTGITN. In an embodiment, CDR H2 has the sequence YHTGITN. In an embodiment, CDR H2 has the sequence ITN. In an embodiment, CDR H2 is as described in SEQ ID NO: 5. In an embodiment, CDR H2 is as described in SEQ ID NO: 16. In an embodiment, CDR H3 has the sequence EVV. In an embodiment, CDR H3 has the sequence EVVG. In an embodiment, CDR H3 has the sequence EVVGP. In an embodiment, CDR H3 has the sequence EVVGPT. In an embodiment, CDR H3 has the sequence EVVGPTT. In an embodiment, CDR H3 has the sequence EVVGPTTG. In an embodiment, CDR H3 has the sequence EVVGPTTGY. In an embodiment, CDR H3 has the sequence VGP. In an embodiment, CDR H3 has the sequence GYF. In an embodiment, CDR H3 has the sequence TGYF. In an embodiment, CDR H3 has the sequence TTGYF. In an embodiment, CDR H3 has the sequence PTTGYF. In an embodiment, CDR H3 has the sequence GPTTGYF. In the embodiment, CDR H3 has the sequence VGPTTGYF. In the embodiment, CDR H3 has the sequence EVVGPTTGYF. In the embodiment, CDR H3 is as described in Sequence ID No. 6.In the embodiment, the antibody further includes a heavy chain framework region comprising HFR2 as described in SEQ ID NO: 12, HFR2 as described in SEQ ID NO: 18, or HFR2 having the sequence WIGE. In the embodiment, HFR2 is as described in SEQ ID NO: 12. In the embodiment, HFR2 is as described in SEQ ID NO: 18. In the embodiment, HFR2 has the sequence WIGE. In the embodiment, the antibody further includes a heavy chain framework region comprising HFR3 as described in SEQ ID NO: 13, HFR3 as described in SEQ ID NO: 19, HFR3 having the sequence ITNYNPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAR, or HFR3 having the sequence ITN. In the embodiment, HFR3 is as described in SEQ ID NO: 13. In the embodiment, HFR3 is as described in SEQ ID NO: 19. In the embodiment, HFR3 has the sequence ITN. In the embodiment, HFR3 has the sequence ITNYNPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAR. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In one embodiment, the antibody is a Fab' fragment. In another embodiment, the antibody is a F(ab)'2 fragment. In yet another embodiment, the antibody is scFv. In yet another embodiment, the antibody is a humanized antibody. In yet another embodiment, the antibody is a chimeric antibody. In yet another embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0069] This disclosure provides an antibody having a fentanyl binding affinity that is greater than or equal to the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In embodiments, this disclosure provides an antibody having a fentanyl binding affinity that is 0% to 25% less than the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In embodiments, the antibody has a fentanyl binding affinity that is 0% to 20% less than the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In embodiments, the antibody has a fentanyl binding affinity that is 0% to 15% less than the fentanyl binding affinity of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In an embodiment, the antibody has a binding affinity to fentanyl that is 0% to 10% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In an embodiment, the antibody has a binding affinity to fentanyl that is 0% to 5% less than the binding affinity to fentanyl of an antibody having the light chain sequence of SEQ ID NO: 22 and the heavy chain sequence of SEQ ID NO: 25. In an embodiment, the binding affinity is determined by the assay described in Example 2. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is a F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In an embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding antibodies described herein, including all embodiments.

[0070] In embodiments, this disclosure provides at least 10 -7 Binding affinity of M to fentanyl (K DProvided are antibodies having -8 a binding affinity (K D ) for fentanyl of at least 10 -9 M. Embodiments provide antibodies having D a binding affinity (K -10 ) for fentanyl of at least 10 D M. Embodiments provide antibodies having -11 a binding affinity (K D ) for fentanyl of at least 10 -7 and so on, repeating the pattern for each set of numbers until

[0071] a binding affinity (K D ) for fentanyl of about 10 -11 M to about 10 -9 M. In embodiments, the binding affinity is determined by the assay described in Example 2. In embodiments, the antibody is an IgG antibody. In embodiments, the antibody is an IgG1 antibody. In embodiments, the antibody is a Fab′ fragment. In embodiments, the antibody is an F(ab)′2 fragment. In embodiments, the antibody is a scFv. In embodiments, the antibody is a humanized antibody. In embodiments, the antibody is a chimeric antibody. In embodiments, the antibody is a monoclonal antibody. Provided herein is a nucleic acid capable of encoding the antibodies described herein, including all embodiments. Provided herein is a vector comprising a nucleic acid capable of encoding the antibodies described herein, including all embodiments.​​​​​​​​​In embodiments, the antibodies described herein include a light chain variable region. In embodiments, the light chain variable region has an amino acid sequence that has at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity with SEQ ID NO: 20. In embodiments, the light chain variable region has an amino acid sequence that has at least 80% sequence identity with SEQ ID NO: 20. In embodiments, the light chain variable region has an amino acid sequence that has at least 85% sequence identity with SEQ ID NO: 20. In embodiments, the light chain variable region has an amino acid sequence that has at least 90% sequence identity with SEQ ID NO: 20. In embodiments, the light chain variable region has an amino acid sequence that has at least 92% sequence identity with SEQ ID NO: 20. In one embodiment, the light chain variable region has an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 20. In another embodiment, the light chain variable region has an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 20. In another embodiment, the light chain variable region has an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 20. In yet another embodiment, the light chain variable region has an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 20. In yet another embodiment, the light chain variable region is SEQ ID NO: 20 and has one or more conservatively modified variants. In yet another embodiment, the light chain variable region is SEQ ID NO: 20 and has 1 to 20 conservatively modified variants. In yet another embodiment, the light chain variable region is SEQ ID NO: 20 and has 1 to 15 conservatively modified variants. In yet another embodiment, the light chain variable region is SEQ ID NO: 20 and has 1 to 10 conservatively modified variants. In yet another embodiment, the light chain variable region is SEQ ID NO: 20 and has 1 to 5 conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In embodiments, the conservatively modified mutation is a conservative substitution. In embodiments, the conservatively modified mutation is an amino acid deletion. In embodiments, the conservatively modified mutation is an amino acid addition.In an embodiment, the light chain variable region includes SEQ ID NO: 20. In an embodiment, the light chain constant region is as described in SEQ ID NO: 20. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is a F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In an embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors containing nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0072] In embodiments, the antibody described herein includes a heavy chain variable region. In embodiments, the heavy chain variable region has an amino acid sequence that has at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity with SEQ ID NO: 23. In embodiments, the heavy chain variable region has an amino acid sequence that has at least 80% sequence identity with SEQ ID NO: 23. In embodiments, the heavy chain variable region has an amino acid sequence that has at least 85% sequence identity with SEQ ID NO: 23. In embodiments, the heavy chain variable region has an amino acid sequence that has at least 90% sequence identity with SEQ ID NO: 23. In embodiments, the heavy chain variable region has an amino acid sequence that has at least 92% sequence identity with SEQ ID NO: 23. In one embodiment, the heavy chain variable region has an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 23. In another embodiment, the heavy chain variable region has an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 23. In another embodiment, the heavy chain variable region has an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 23. In another embodiment, the heavy chain variable region has an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 23. In another embodiment, the heavy chain variable region is SEQ ID NO: 23 and has one or more conservatively modified variants. In another embodiment, the heavy chain variable region is SEQ ID NO: 23 and has 1 to 20 conservatively modified variants. In another embodiment, the heavy chain variable region is SEQ ID NO: 23 and has 1 to 15 conservatively modified variants. In another embodiment, the heavy chain variable region is SEQ ID NO: 23 and has 1 to 10 conservatively modified variants. In another embodiment, the heavy chain variable region is SEQ ID NO: 23 and has 1 to 5 conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In embodiments, the conservatively modified mutation is a conservative substitution. In embodiments, the conservatively modified mutation is an amino acid deletion. In embodiments, the conservatively modified mutation is an amino acid addition.In the embodiment, the heavy chain variable region includes SEQ ID NO: 23. In the embodiment, the heavy chain constant region is as described in SEQ ID NO: 23. In the embodiment, the antibody is an IgG antibody. In the embodiment, the antibody is an IgG1 antibody. In the embodiment, the antibody is a Fab' fragment. In the embodiment, the antibody is a F(ab)'2 fragment. In the embodiment, the antibody is scFv. In the embodiment, the antibody is a humanized antibody. In the embodiment, the antibody is a chimeric antibody. In the embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors containing nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0073] In embodiments, the antibody described herein includes a light chain constant region. In embodiments, the light chain constant region has an amino acid sequence that has at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity with SEQ ID NO: 21. In embodiments, the light chain constant region has an amino acid sequence that has at least 80% sequence identity with SEQ ID NO: 21. In embodiments, the light chain constant region has an amino acid sequence that has at least 85% sequence identity with SEQ ID NO: 21. In embodiments, the light chain constant region has an amino acid sequence that has at least 90% sequence identity with SEQ ID NO: 21. In embodiments, the light chain constant region has an amino acid sequence that has at least 92% sequence identity with SEQ ID NO: 21. In one embodiment, the light chain constant region has an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 21. In another embodiment, the light chain constant region has an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 21. In yet another embodiment, the light chain constant region has an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 21. In yet another embodiment, the light chain constant region has an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 21. In yet another embodiment, the light chain constant region is SEQ ID NO: 21 and has one or more conservatively modified variants. In yet another embodiment, the light chain constant region is SEQ ID NO: 21 and has 1 to 20 conservatively modified variants. In yet another embodiment, the light chain constant region is SEQ ID NO: 21 and has 1 to 21 conservatively modified variants. In yet another embodiment, the light chain constant region is SEQ ID NO: 21 and has 1 to 10 conservatively modified variants. In yet another embodiment, the light chain constant region is SEQ ID NO: 21 and has 1 to 5 conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In embodiments, the conservatively modified mutation is a conservative substitution. In embodiments, the conservatively modified mutation is an amino acid deletion. In embodiments, the conservatively modified mutation is an amino acid addition.In an embodiment, the light chain constant region includes SEQ ID NO: 21. In an embodiment, the light chain constant region is as described in SEQ ID NO: 21. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is a F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In an embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors comprising nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0074] In embodiments, the antibody described herein includes a heavy chain constant region. In embodiments, the heavy chain constant region has an amino acid sequence that has at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 88%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity with SEQ ID NO: 24. In embodiments, the heavy chain constant region has an amino acid sequence that has at least 80% sequence identity with SEQ ID NO: 24. In embodiments, the heavy chain constant region has an amino acid sequence that has at least 85% sequence identity with SEQ ID NO: 24. In embodiments, the heavy chain constant region has an amino acid sequence that has at least 90% sequence identity with SEQ ID NO: 24. In embodiments, the heavy chain constant region has an amino acid sequence that has at least 92% sequence identity with SEQ ID NO: 24. In one embodiment, the heavy chain constant region has an amino acid sequence having at least 94% sequence identity with SEQ ID NO: 24. In another embodiment, the heavy chain constant region has an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 24. In another embodiment, the heavy chain constant region has an amino acid sequence having at least 96% sequence identity with SEQ ID NO: 24. In yet another embodiment, the heavy chain constant region has an amino acid sequence having at least 98% sequence identity with SEQ ID NO: 24. In yet another embodiment, the heavy chain constant region is SEQ ID NO: 24 and has one or more conservatively modified variants. In yet another embodiment, the heavy chain constant region is SEQ ID NO: 24 and has 1 to 20 conservatively modified variants. In yet another embodiment, the heavy chain constant region is SEQ ID NO: 24 and has 1 to 15 conservatively modified variants. In yet another embodiment, the heavy chain constant region is SEQ ID NO: 24 and has 1 to 10 conservatively modified variants. In yet another embodiment, the heavy chain constant region is SEQ ID NO: 24 and has 1 to 5 conservatively modified variants. As described herein, conservatively modified variants include conservative substitutions, amino acid deletions, amino acid additions, or combinations of two or more thereof. In embodiments, the conservatively modified mutation is a conservative substitution. In embodiments, the conservatively modified mutation is an amino acid deletion. In embodiments, the conservatively modified mutation is an amino acid addition.In an embodiment, the heavy chain constant region includes SEQ ID NO: 24. In an embodiment, the heavy chain constant region is as described in SEQ ID NO: 24. In an embodiment, the antibody is an IgG antibody. In an embodiment, the antibody is an IgG1 antibody. In an embodiment, the antibody is a Fab' fragment. In an embodiment, the antibody is a F(ab)'2 fragment. In an embodiment, the antibody is scFv. In an embodiment, the antibody is a humanized antibody. In an embodiment, the antibody is a chimeric antibody. In an embodiment, the antibody is a monoclonal antibody. This specification provides nucleic acids capable of encoding the antibodies described herein, including all embodiments. This specification provides vectors containing nucleic acids capable of encoding the antibodies described herein, including all embodiments.

[0075] complex This specification provides complexes comprising the antibodies (including embodiments and models thereof) and opioids described herein. As described herein, the antibodies of this disclosure form antibody-opioid complexes by binding to fentanyl, fentanyl analogs, carfentanyl, or carfentanyl analogs. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and synthetic opioids described herein. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and fentanyl, fentanyl analogs, carfentanyl, or carfentanyl analogs described herein. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and fentanyl. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and carfentanyl. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and fentanyl analogs. In embodiments, this disclosure provides the antibodies (including embodiments and models thereof) and carfentanyl analogs described herein. In one embodiment, the fentanyl analog is acetylfentanyl, alfentanyl, butylfentanyl, butylfentanyl, para-tolylfentanyl, 3-methylfentanyl, α-methylfentanyl, remifentanyl, mefentanyl, phenaridine, omefentanyl, or milfentanyl. In another embodiment, the carfentanyl analog is sufentanyl, remifentanyl, alfentanyl, lofentanyl, brifentanyl, or trefentanyl.

[0076] nucleic acid This specification provides isolated nucleic acids encoding antibodies provided herein, including embodiments and aspects thereof. For example, the nucleic acid may encode at least one CDR, a specific residue involved in binding to an epitope, or a binding framework residue.

[0077] In one embodiment, the nucleic acid has at least 75% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 80% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 85% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 90% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 92% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 94% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 95% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 96% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid has at least 98% sequence identity with SEQ ID NO: 26. In another embodiment, the nucleic acid includes SEQ ID NO: 26. In another embodiment, the nucleic acid is as described in SEQ ID NO: 26. This specification provides vectors comprising nucleic acids capable of encoding antibodies described herein, including all embodiments.

[0078] In an embodiment, the nucleic acid has at least 75% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 80% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 85% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 90% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 92% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 94% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 95% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 96% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid has at least 98% sequence identity with SEQ ID NO: 27. In an embodiment, the nucleic acid includes SEQ ID NO: 27. In an embodiment, the nucleic acid is as described in SEQ ID NO: 27. This specification provides vectors comprising nucleic acids capable of encoding antibodies described herein, including all embodiments.

[0079] In an embodiment, the nucleic acid has at least 75% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 80% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 85% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 90% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 92% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 94% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 95% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 96% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid has at least 98% sequence identity with SEQ ID NO: 28. In an embodiment, the nucleic acid includes SEQ ID NO: 28. In an embodiment, the nucleic acid is as described in SEQ ID NO: 28. This specification provides vectors comprising nucleic acids capable of encoding antibodies described herein, including all embodiments.

[0080] Treatment method In an embodiment, the Disclosure provides a method for treating opioid overdose in a patient requiring treatment by administering to the patient an effective amount of the antibody described herein. In an embodiment, the Disclosure provides a method for treating opioid overdose in a patient requiring treatment by administering to the patient a pharmaceutical composition comprising an effective amount of the antibody described herein and a pharmaceutically acceptable excipient. The method for treating opioid overdose may also be referred to as a method for recovering from opioid overdose by administering the antibody described herein to a patient experiencing opioid overdose. In an embodiment, the opioid is fentanyl, a fentanyl analog, carfentanyl, a carfentanyl analog, or a combination of two or more thereof. In an embodiment, the opioid is fentanyl or a fentanyl analog. In an embodiment, the opioid is fentanyl. In an embodiment, the opioid is a fentanyl analog. In an embodiment, the opioid is carfentanyl or a carfentanyl analog. In one embodiment, the opioid is a carfentanil analog.

[0081] In an embodiment, the Disclosure provides a method for preventing opioid overdose in a patient requiring treatment by administering to the patient an effective amount of the antibody described herein. In an embodiment, the Disclosure provides a method for preventing opioid overdose in a patient requiring treatment by administering to the patient a pharmaceutical composition comprising an effective amount of the antibody described herein and a pharmaceutically acceptable excipient. In an embodiment, the opioid is fentanyl, a fentanyl analog, carfentanyl, a carfentanyl analog, or a combination of two or more thereof. In an embodiment, the opioid is fentanyl or a fentanyl analog. In an embodiment, the opioid is fentanyl. In an embodiment, the opioid is a fentanyl analog. In an embodiment, the opioid is carfentanyl or a carfentanyl analog. In an embodiment, the opioid is a carfentanyl analog.

[0082] In an embodiment, the Disclosure provides a method for treating opioid use disorder in a patient requiring treatment by administering to the patient an effective amount of the antibody described herein. In an embodiment, the Disclosure provides a method for treating opioid use disorder in a patient requiring treatment by administering to the patient a pharmaceutical composition comprising an effective amount of the antibody described herein and a pharmaceutically acceptable excipient. In an embodiment, the opioid is fentanyl, a fentanyl analog, carfentanyl, a carfentanyl analog, or a combination of two or more thereof. In an embodiment, the opioid is fentanyl or a fentanyl analog. In an embodiment, the opioid is fentanyl. In an embodiment, the opioid is a fentanyl analog. In an embodiment, the opioid is carfentanyl or a carfentanyl analog. In an embodiment, the opioid is a carfentanyl analog.

[0083] In embodiments, the Disclosure provides a method for treating opioid-induced respiratory depression by administering an effective amount of the antibody described herein to a patient. In embodiments, the Disclosure provides a method for treating opioid-induced respiratory depression by administering to a patient a pharmaceutical composition comprising an effective amount of the antibody described herein and a pharmaceutically acceptable excipient. The method may also be referred to as a method for reducing opioid-induced respiratory depression. In embodiments, the opioid is fentanyl, a fentanyl analog, carfentanyl, a carfentanyl analog, or a combination of two or more thereof. In embodiments, the opioid is fentanyl or a fentanyl analog. In embodiments, the opioid is fentanyl. In embodiments, the opioid is a fentanyl analog. In embodiments, the opioid is carfentanyl or a carfentanyl analog. In embodiments, the opioid is a carfentanyl analog.

[0084] In embodiments, the Disclosure provides a method for preventing opioid-induced respiratory depression by administering an effective amount of the antibody described herein to a patient. In embodiments, the Disclosure provides a method for preventing opioid-induced respiratory depression by administering to a patient a pharmaceutical composition comprising an effective amount of the antibody described herein and a pharmaceutically acceptable excipient. In embodiments, the opioid is fentanyl, a fentanyl analog, carfentanyl, a carfentanyl analog, or a combination of two or more thereof. In embodiments, the opioid is fentanyl or a fentanyl analog. In embodiments, the opioid is fentanyl. In embodiments, the opioid is a fentanyl analog. In embodiments, the opioid is carfentanyl or a carfentanyl analog. In embodiments, the opioid is a carfentanyl analog.

[0085] As used herein, the term “administer” means oral administration, suppository administration, topical contact, intravenous, parenteral, intraperitoneal, intrafocal, intrathecal, intranasal, or subcutaneous administration to a subject. Administration is by any route, including parenteral and transmucosal (e.g., oral, sublingual, palatal, gingival, transnasal, transvaginal, rectal, or transdermal). Parenteral administration includes, for example, intravenous, intramuscular, intraarteriole, intradermal, subcutaneous, intraperitoneal, intraventricular, and intracranial. Other modes of delivery include, but are not limited to, liposomal formulations, intravenous injection, and transdermal patches. In embodiments, administration does not include the administration of activators other than those listed.

[0086] The terms “to treat” or “treatment” refer to signs of success in treating or improving a disease, condition, or state, including objective or subjective parameters such as reduction; remission; reduction of symptoms, or making the injury, lesion, or condition more tolerable to the patient; slowing the rate of degeneration or decline; mitigation of the final stage of degeneration; and improvement of the patient’s physical or mental health. Treatment or improvement of symptoms may be based on objective or subjective parameters; the results of physical examinations, neuropsychiatric examinations, and / or psychiatric evaluations, etc. The terms “to treat” and their inflections may include prevention of a condition, state, or disease. In embodiments, treatment is prevention. In embodiments, treatment does not include prevention.

[0087] As used herein (and as well understood in the art), “to treat” or “treatment” also broadly includes any approach to obtain a beneficial or desired outcome in the condition of a subject, including clinical outcomes. Beneficial or desired clinical outcomes may include, but are not limited to, relief or improvement of one or more symptoms or conditions, whether partial or complete, and whether detectable or undetectable; reduction of the severity of the disease; stabilization of the disease state (i.e., no exacerbation); prevention of transmission or spread of the disease; delay or slowing of disease progression; improvement or relief of the disease state; reduction of disease recurrences; and remission. In other words, as used herein, “treatment” includes any cure, improvement, or prevention of disease. Treatment may prevent the onset of disease; control the spread of disease; alleviate the symptoms of disease; completely or partially eliminate the underlying cause of the disease; shorten the duration of the disease; or do a combination of these.

[0088] As used herein, “to treat” and “treatment” include prophylactic measures. A treatment method involves administering a therapeutically effective amount of an activator to a subject. The administration stage may consist of a single dose or may include a series of doses. The length of the treatment period depends on various factors, such as the severity of the condition, the patient’s age, the concentration of the activator, the activity of the composition used for treatment, or a combination thereof. It will also be understood that the effective dose of the agent used for treatment or prevention may be increased or decreased during the course of a particular treatment or prevention method. Changes in dosage may be produced and revealed by standard diagnostic assays known in the art. In some cases, long-term administration may be necessary. For example, the composition is administered to the subject in an amount and duration sufficient to treat the patient. In embodiments, treatment or therapy is not a prophylactic measure.

[0089] The term "prevention" refers to a reduction in the occurrence of disease symptoms in a patient. As mentioned above, prevention can be complete (no detectable symptoms) or partial, resulting in fewer observed symptoms that are likely to occur without treatment.

[0090] "Patient" or "subject requiring treatment" means an organism that is suffering from or susceptible to a disease or condition that can be treated by administration of the pharmaceutical compositions provided herein. Non-limiting examples include, but are not limited to, humans, other mammals, cattle, rats, mice, dogs, monkeys, goats, sheep, deer, and other non-mammals. In some embodiments, the patient is human.

[0091] With reference to the Diagnostic and Statistical Manual for Mental Disorders, 5th Edition, American Psychiatric Association, 2013 (also referred to herein as DSM-5) [the disclosures thereof are incorporated herein by reference in their entirety], “Opioid Use Disorder” is characterized by signs and symptoms that reflect compulsive, long-term self-administration of opioid substances, either not used for legitimate medical purposes or, if another condition requiring opioid treatment exists, in doses significantly exceeding those required for that medical condition. In some embodiments, opioid use disorder is moderate opioid use disorder. “Moderate opioid use disorder” is defined with reference to the DSM-5 Opioid Use Disorder Checklist (ICD-9-CM code 304.00 or ICD-10-CM code F11.20), as having the presence of four or five symptoms as shown on the DSM-5 Opioid Use Disorder Checklist. In some cases, opioid use disorder is severe opioid use disorder. Severe opioid use disorder is defined as the presence of six or more symptoms listed on the DSM-5 Opioid Use Disorder Checklist (ICD-9-CM code 304.00 or ICD-10-CM code F11.20), with reference to the DSM-5 Opioid Use Disorder Checklist. In some cases, opioid use disorder is moderate to severe opioid use disorder. Moderate to severe opioid use disorder refers to the presence of four or more symptoms listed on the DSM-5 Opioid Use Disorder Checklist. In some cases, opioid use disorder is mild opioid use disorder. "Mild opioid use disorder" is defined as the presence of two or three symptoms listed on the DSM-5 Opioid Use Disorder Checklist (ICD-9-CM code 305.50 or ICD-10-CM code F11.10), with reference to the DSM-5 Opioid Use Disorder Checklist. In some cases, opioid use disorder is mild to moderate opioid use disorder. Mild to moderate opioid use disorder refers to the presence of two to five symptoms listed on the DSM-5 Opioid Use Disorder Checklist.In practice, “treating opioid use disorder” includes one or more of the following: (i) reducing opioid withdrawal symptoms, (ii) eliminating opioid withdrawal symptoms, (iii) reducing opioid cravings, (iv) eliminating opioid cravings, (v) reducing illicit opioid use, (vi) eliminating illicit opioid use, and (vii) inducing opioid abstinence. The term “opioid use disorder” can be used interchangeably with the terms “opioid addiction” or “opioid dependence.”

[0092] composition This specification provides compositions comprising antibodies (including embodiments and forms thereof) and pharmaceutically acceptable excipients as described herein.

[0093] "Pharmacovigilantly acceptable excipients" and "pharmacovigilantly acceptable carriers" refer to substances that assist in the administration and absorption of activators to subjects and may be included in the compositions of this disclosure as long as they do not cause serious adverse toxic effects in the patient. Non-limiting examples of pharmacovigilantly acceptable excipients include water, NaCl, physiological saline, lactated Ringer's solution, ordinary sucrose, ordinary glucose, binders, fillers, disintegrants, lubricants, coatings, sweeteners, flavorings, salt solutions (such as Ringer's solution), alcohols, oils, gelatin, carbohydrates such as lactose, amylose or starch, fatty acid esters, hydroxymethylcellulose, polyvinylpyrrolidine, and dyes. Such compositions may be sterilized and, if necessary, mixed with auxiliary agents such as lubricants, preservatives, stabilizers, wetting agents, emulsifiers, salts affecting osmotic pressure, buffers, colorants, and / or fragrances that do not react adversely with the antibodies of this disclosure. Those skilled in the art will recognize that other pharmaceutical excipients may be useful.

[0094] Antibody solutions can be prepared in water, suitably mixed with a surfactant such as hydroxypropyl cellulose. Dispersions can also be prepared in glycerol, liquid polyethylene glycol, and mixtures thereof, and in oil. Under normal storage and use conditions, these compositions may contain preservatives to prevent microbial growth.

[0095] For parenteral administration in aqueous solutions, for example, the solution needs to be appropriately buffered, and the liquid diluent must first be isotonic with sufficient physiological saline or glucose. Aqueous solutions, especially sterile aqueous media, are particularly suitable for intravenous, intramuscular, subcutaneous, and intraperitoneal administration. For example, one dose can be dissolved in 1 mL of isotonic NaCl solution and added to 1000 mL of subcutaneous injection solution, or injected into the intended injection site.

[0096] Sterile injectable solutions can be prepared by incorporating the required amount of antibody into a suitable solvent, followed by sterilization by filtration. Generally, dispersions are prepared by incorporating the antibody into a sterile vehicle containing a basic dispersion medium. Sterile powders for regenerating sterile injectable solutions can be prepared using vacuum drying and freeze-drying techniques to produce powders of the active ingredient and any additional desired ingredients. More concentrated or highly concentrated solution compositions for direct injection are also conceivable. By using solvents such as dimethyl sulfoxide, very rapid penetration and delivery of high concentrations of the active ingredient to a small area are possible.

[0097] Pharmaceutical compositions can be delivered intranasally or via inhalable solutions or sprays, aerosols, or inhalants. Nasal sprays can be aqueous solutions designed to be administered into the nasal cavity by drip or spray. Nasal sprays can be prepared to resemble nasal secretions in many respects. Therefore, nasal aqueous solutions are usually isotonic and slightly buffered to maintain a pH of 5.5–6.5. Furthermore, antimicrobial preservatives and appropriate drug stabilizers, similar to those used in ophthalmic compositions, may be included in the formulation as needed. Various commercially available nasal compositions are known.

[0098] Oral formulations may include excipients such as pharmaceutical mannitol, lactose, starch, magnesium stearate, sodium saccharin, cellulose, and magnesium carbonate. These compositions may take the form of liquids, suspensions, tablets, pills, capsules, sustained-release formulations, or powders. In some embodiments, oral pharmaceutical compositions may contain inert diluents or food carriers, which can be encapsulated in hard-shell or soft-shell gelatin capsules, compressed into tablets, or directly incorporated into food. For oral therapeutic administration, antibodies may be mixed with excipients and used in the form of ingestible tablets, oral tablets, lozenges, capsules, elixirs, suspensions, syrups, wafers, etc. The percentage of the composition can, of course, vary and, conveniently, may be about 1 to about 75% of the weight of the unit. The amount of antibody in such a composition is such that an appropriate dose can be obtained.

[0099] Antibody preparations may be provided in sealed containers of unit doses or multiple doses, such as ampoules and vials. Therefore, compositions can be in unit dosage forms. In such forms, the composition is divided into unit doses containing an appropriate amount of antibody. Thus, the composition can be administered in a variety of unit dosage forms depending on the method of administration.

[0100] Dosage Pharmaceutical compositions include those containing an active ingredient (i.e., an antibody) in a therapeutically effective amount, that is, an amount effective in achieving its intended purpose. The actual amount effective for a particular application is determined by the condition being treated, as is often determined by medical practitioners.

[0101] An “effective dose” is the amount of antibody sufficient to achieve the stated purpose compared to the absence of the compound (e.g., to achieve the effect it is administered, to treat a disease, or to alleviate one or more symptoms of a disease or condition). An example of an “effective dose” is an amount sufficient to contribute to the treatment, prevention, or alleviation of one or more symptoms of a disease, which may also be called a “therapeutic effective dose.” “Alleviation” (and its grammatical equivalent) of one or more symptoms means a reduction in the severity or frequency of a symptom, or the elimination of a symptom. A “prophylactic effective dose” of an antibody is the amount of antibody, when administered to a subject, that has an intended prophylactic effect, such as preventing or delaying the onset (or recurrence) of a disease, condition, or condition, or reducing the likelihood of the onset (or recurrence) of a disease, condition, condition, or its symptoms. Complete prophylactic effect is not necessarily achieved with a single dose and may only occur after a series of doses have been administered. Therefore, a prophylactic effective dose may be administered in one or more doses. The exact amount is determined by the purpose of treatment and can be determined by those skilled in the art using known techniques (see, for example, Lieberman, Pharmaceutical Dosage Forms (vols. 1-3, 1992); Lloyd, The Art, Science and Technology of Pharmaceutical Compounding (1999); Pickar, Dosage Calculations (1999); and Remington: The Science and Practice of Pharmacy, 20th Edition, 2003, Gennaro, Ed., Lippincott, Williams & Wilkins).

[0102] For any antibody described herein, the therapeutically effective dose can first be determined from a cell culture assay. The target concentration is the concentration of antibody that can achieve the method described herein, measured using the method described herein or a method known in the art. As known in the art, the therapeutically effective dose for use in humans can also be determined from an animal model. For example, a human dose can be formulated to achieve a concentration known to be effective in animals. The dose in humans can be adjusted by monitoring efficacy as described above and adjusting the dose upward or downward. Adjusting the dose to achieve maximum efficacy in humans based on the above and other methods is well within the capabilities of those skilled in the art.

[0103] The dosage and frequency of antibody administration (single or multiple doses) can be varied according to the patient's needs. The dose administered to the patient must be sufficient to influence the patient's beneficial therapeutic response over the long term. The size of the dose is also determined by the presence, nature, and severity of adverse side effects. Determining the appropriate dosage for a particular situation is within the scope of the art of this industry. Generally, treatment is initiated with a relatively small dose, less than the optimal dose of antibody. The dose is then gradually increased until the optimal effect is achieved under the circumstances. The dosage and administration interval can be individually adjusted to provide an effective antibody level for the specific clinical indication being treated. This provides a treatment method that is appropriate to the severity of the individual's condition. In embodiments, the antibody is administered in amounts ranging from approximately 0.001 μg to approximately 10,000 μg.

[0104] Using the teachings provided herein, effective preventive or therapeutic measures can be planned that cause little to no toxicity and are effective in treating the clinical symptoms exhibited by specific patients. This planning requires careful selection of monoclonal antibodies, taking into account factors such as the potency of the compound, relative bioavailability, patient weight, and the presence and severity of side effects.

[0105] Embodiments 1-31: Embodiment 1: (i) A light chain variable region comprising CDR L1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 3; and (ii) An antibody comprising a heavy chain variable region comprising CDR H1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 15, CDR H2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 16, and CDR H3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 6.

[0106] Embodiment 2: (i) The antibody of Embodiment 1, wherein the light chain variable region comprises CDR L1 described in SEQ ID NO: 1, CDR L2 described in SEQ ID NO: 2, and CDR L3 described in SEQ ID NO: 3; and (ii) The heavy chain variable region comprises CDR H1 described in SEQ ID NO: 15, CDR H2 described in SEQ ID NO: 16, and CDR H3 described in SEQ ID NO: 6.

[0107] Embodiment 3: The antibody of Embodiment 1 or 2, further comprising a light chain framework region including LFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 10.

[0108] Embodiment 4: The antibody of Embodiment 3, wherein the light chain framework region comprises LFR1 as described in SEQ ID NO: 7, LFR2 as described in SEQ ID NO: 8, LFR3 as described in SEQ ID NO: 9, and LFR4 as described in SEQ ID NO: 10.

[0109] Embodiment 5: Any one antibody from Embodiments 1 to 4, further comprising a heavy chain framework region including HFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 17; HFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 18; HFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 19; and HFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 14.

[0110] Embodiment 6: The antibody of Embodiment 5, wherein the heavy chain framework region comprises HFR1 as described in SEQ ID NO: 17; HFR2 as described in SEQ ID NO: 18; HFR3 as described in SEQ ID NO: 19; and HFR4 as described in SEQ ID NO: 14.

[0111] Embodiment 7: (i) an antibody comprising a light chain variable region including CDR L1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 1, CDR L2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 2, and CDR L3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 3; and (ii) an antibody comprising a heavy chain variable region including CDR H1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 4, CDR H2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 5, and CDR H3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 6.

[0112] Embodiment 8: The antibody of Embodiment 7, wherein (i) a light chain variable region comprising CDR L1 described in SEQ ID NO: 1, CDR L2 described in SEQ ID NO: 2, and CDR L3 described in SEQ ID NO: 3; and (ii) a heavy chain variable region comprising CDR H1 described in SEQ ID NO: 4, CDR H2 described in SEQ ID NO: 5, and CDR H3 described in SEQ ID NO: 6.

[0113] Embodiment 9: The antibody of Embodiment 7 or 8, further comprising a light chain framework region including LFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 10.

[0114] Embodiment 10: The antibody of Embodiment 9, wherein the light chain framework region comprises LFR1 as described in SEQ ID NO: 7, LFR2 as described in SEQ ID NO: 8, LFR3 as described in SEQ ID NO: 9, and LFR4 as described in SEQ ID NO: 10.

[0115] Embodiment 11: Any one antibody from Embodiments 7 to 10, further comprising a heavy chain framework region including HFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 11; HFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 12; HFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 13; and HFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 14.

[0116] Embodiment 12: The antibody of Embodiment 11, wherein the heavy chain framework region comprises HFR1 as described in SEQ ID NO: 11; HFR2 as described in SEQ ID NO: 12; HFR3 as described in SEQ ID NO: 13; and HFR4 as described in SEQ ID NO: 14.

[0117] Embodiment 13: An antibody comprising a light chain variable region having at least 85% sequence identity with SEQ ID NO: 20 and a heavy chain variable region having at least 85% sequence identity with SEQ ID NO: 23.

[0118] Embodiment 14: The antibody of Embodiment 13, wherein the light chain variable region includes SEQ ID NO: 20 and the heavy chain variable region includes SEQ ID NO: 23.

[0119] Embodiment 15: Any one of Embodiments 1 to 14, further comprising a light chain constant region having an amino acid sequence having at least 85% identity with SEQ ID NO: 21.

[0120] Embodiment 16: The antibody of Embodiment 15, wherein the light chain constant region includes SEQ ID NO: 21.

[0121] Embodiment 17: Any one of Embodiments 1 to 16, further comprising a heavy chain constant region having at least 85% identity with SEQ ID NO: 24.

[0122] Embodiment 18: The antibody of Embodiment 17, wherein the heavy chain constant region includes SEQ ID NO: 24.

[0123] Embodiment 19: Any one of Embodiments 1 to 18, wherein the antibody is an IgG antibody.

[0124] Embodiment 20: The antibody of Embodiment 19, wherein the IgG antibody is an IgG1 antibody.

[0125] Embodiment 21: An antibody from any one of Embodiments 1 to 20, wherein the antibody is a Fab' fragment or an F(ab)'2 fragment.

[0126] Embodiment 22: An antibody from any one of Embodiments 1 to 19, wherein the antibody is a single-stranded variable fragment.

[0127] Embodiment 23: Any one of Embodiments 1 to 22, wherein the antibody is a humanized monoclonal antibody.

[0128] Embodiment 24: A pharmaceutical composition comprising one antibody from Embodiments 1 to 23 and a pharmaceutically acceptable excipient.

[0129] Embodiment 25: A method for treating or preventing opioid overdose in a patient requiring treatment, comprising administering to the patient an effective amount of one antibody from Embodiments 1 to 23 or the pharmaceutical composition of Embodiment 24.

[0130] Embodiment 26: A method for treating opioid use disorder in a patient requiring treatment, comprising administering to the patient an effective amount of one antibody from Embodiments 1 to 23 or the pharmaceutical composition of Embodiment 24.

[0131] Embodiment 27: A method for treating or preventing opioid-induced respiratory depression in a patient requiring treatment, comprising administering to the patient an effective amount of one antibody from Embodiments 1 to 23 or the pharmaceutical composition of Embodiment 24.

[0132] Embodiment 28: An isolated nucleic acid encoding one of the antibodies from Embodiments 1 to 23.

[0133] Embodiment 29: An isolated nucleic acid having a nucleic acid sequence having at least 85% sequence identity with SEQ ID NO: 26, SEQ ID NO: 27, or SEQ ID NO: 28.

[0134] Embodiment 30: A vector comprising a nucleic acid encoding one of the antibodies from Embodiments 1 to 23.

[0135] Embodiment 31: (i) one antibody from any of Embodiments 1 to 23; and (ii) a complex comprising fentanyl, a fentanyl analog, carfentanyl, or a carfentanyl analog. [Examples]

[0136] The anti-opioid mAbs described herein have high binding affinity to fentanyl, carfentanyl, and related analogues, and can therefore effectively mitigate the adverse effects of synthetic opioids. It is believed that injecting the mAbs into a patient can either immediately treat opioid overdose or protect the patient from subsequent opioid exposure. In the latter case, the patient would likely receive protection not only from the acute lethal effects of high-dose fentanyl but also from the toxic effects of low-dose fentanyl. Therefore, anti-opioid mAbs can be used as antidotes for synthetic opioids and as a treatment for opioid use disorder.

[0137] The high potency and long duration of action of fentanyl and other synthetic opioids have diminished the effectiveness of current opioid overdose treatments such as naloxone. Anti-opioid mAbs are highly effective in combating opioid addiction because they possess picomolar affinity for target opioids, thus sequestering the drug in the peripheral blood and preventing its access to the site of action in the brain. Furthermore, because mAbs do not bind to endogenous targets in the body, they offer a very favorable safety profile. IgG human antibodies generally exhibit a duration of action of one month. Therefore, anti-opioid mAbs are considered capable of protecting patients from opioid addiction for a much longer period than current drug therapies.

[0138] Example 1 The antibodies described herein were prepared by immunizing rats with a carfentanil-conjugated vaccine, selecting / sequencing B cells with a combination of carfentanil and fentanylbiotin probes, and redesigning the antibodies in a phage display library containing human antibody sequences. The method is described, for example, in WO2017 / 127390, WO2020 / 018596, and Smith et al, ``Monoclonal Antibodies for Combating Synthetic Opioid Intoxication'' J. Am. Chem. Soc., 141(26):10489-10503 (2019).

[0139] Example 2 The binding reaction rates for selected mAbs, fentanyl, and their derivatives were determined by SPR using a Biacore 8K instrument (GE Healthcare Life Sciences) equipped with a Series S CM5 sensor chip. Selected mAbs were immobilized on individual channels of the sensor chip surface using the Amine Coupling Kit as follows: The flow cell 2 surface of each channel was activated for 7 minutes with a 1:1 mixture of 0.1 M NHS and 0.4 M EDC at a flow rate of 10 μL / min, while the flow cell 1 of each channel was left unactivated. Selected mAbs, resuspended in 10 mM sodium acetate (pH 5.5), were injected separately into the activated Fc2 at 10 μL / min for 120 seconds for each channel. All flow cell surfaces were blocked by injection of 1.0 M ethanolamine-HCl (pH 8.5) at a flow rate of 10 μL / min for 7 minutes. All assays were performed at 25°C and 37°C at a flow rate of 30 μL / min using 1× PBS-P+ buffer (28-9950-84, GE Healthcare Life Sciences) as the running buffer. To determine the binding reaction rate, a predetermined single-cycle kinetics method (SCK, Biacore 8K control software version 1.1.1.7442) was used at the following four analyte concentrations: 1) 4× initiation cycles (each cycle included 300 seconds of running buffer injection and 600 seconds of dissociation at a flow rate of 30 μL / min, with the tip surface regenerated with Gly-HCl (pH 1.5) for 30 seconds) were performed before SCK analysis. 2) For SCK analysis, fentanyl and carfentanyl or related analogs were prepared in running buffer at concentrations of 1.25, 5, 20, and 80 nM. The compound dilutions were injected consecutively for 120 seconds, followed by dissociation in running buffer for 10800 seconds. 3) The sensor tip surface was regenerated by injecting Gly-HCl (pH 1.5) solution for 30 seconds, and then the next cycle of SCK analysis was performed. Using the exact same conditions as the SCK analysis, a blank running buffer was also injected before analyzing each compound, and then the compound runs were performed.

[0140] All data were collected in a results file by Biacore control software. The run datasets stored in the results file were then analyzed using Biacore 8K evaluation software (version 1.1.1.7442) with a predetermined fragment / LWM single-cycle kinetics. Each SCK analysis dataset was dual-referenced with signals from reference Fc1 and blank running buffer injection and fitted using a 1:1 binding model. Table 1 shows the structures of fentanyl, carfentanyl, and related analogues. Tables 2A-2C show the direct binding reaction rates of immobilized mAbs to free fentanyl compounds.

[0141] [Table 1]

[0142] [Table 2]

[0143] [Table 3]

[0144] [Table 4]

[0145] The direct binding kinetics of JBZ-4 to fentanyl and related analogues were fully characterized by surface plasmon resonance (SPR) single-cycle reaction kinetics, in which the antibody was immobilized on the sensor chip surface by amide bonds, and various dilutions of the compound (40, 20, 10, 5, 2.5 nM) were flowed through the sensor. By fitting a 1:1 binding model to the data, association (k on ) and dissociation (k off By determining the rate, the affinity constant (K) determined for each compound can be found. d) was obtained (Table 2D). An exemplary sensorgram of the direct binding reaction of JBZ-4 to fentanyl is shown in Figure 8A, and for carfentanyl it is shown in Figure 8B. The affinity for fentanyl analogs was typically in the picomolar (pM) range.

[0146] [Table 5]

[0147] Fentanyl-BSA complexes were immobilized on the sensor surface, and binding selectivity was measured by a competitive SPR assay in which JBZ-4 antibodies mixed with various compounds were flowed onto the chip surface. As shown in Table 2E, 16 nM fentanyl or carfentanyl completely inhibited sensor ligand binding, but compound binding hardly occurred even with non-fentanyl molecules at concentrations exceeding 1000 times. Binding selectivity was typically measured for each molecule at 10 4 The ratio was more than double, however, due to very poor antibody binding to non-fentanyl molecules, it was not possible to determine an accurate value.

[0148] [Table 6]

[0149] Example 3 We conducted rhesus monkey antinociceptive experiments according to the method previously reported (Tenney et al, Neuropharmacology. 2019;158:107730). Monkeys were intravenously administered fentanyl at doses of 0.1–0.18 mg / kg, followed by intravenous injection of 8 mg / kg of JBZ-1 or a control mAb. The effect of the antibody on antinociceptiveness was tracked for the first 100 minutes after fentanyl injection, and on days 2, 7, and 14. Blood samples collected from the monkeys were analyzed by ELISA for fentanyl-BSA capture antigen using corresponding antibodies to create a calibration curve. The effect on tail-retraction antinociceptiveness was observed and is shown in Figure 1A. As shown in Figure 1B, cumulative dose fentanyl ED50 This was measured in the same monkey at three time points after mAb injection. Blood samples were collected from the monkeys and analyzed by ELISA to determine the antibody concentration at the specified time points shown in Figure 1C.

[0150] Example 4 Female Swiss Webster mice (n=4 per group) were intravenously administered 30 mg / kg mAb via tail vein injection, and 48 hours later, 0.1 mg / kg fentanyl citrate tail fentanyl was administered via tail vein injection. After fentanyl administration, blood was collected at the specified time and prepared as follows: Frozen mouse blood samples were thawed on ice, and 60 μL of blood was pipetteed into a new tube with 8 μL of 50 ng / mL fentanyl-d5 in methanol. After vortex stirring, 120 μL of 50 mM K2003 solution and 420 μL of 7:3 hexane / ethyl acetate were added. The sample was vortex stirred for 15 seconds and centrifuged at 3000 rpm for 5 minutes. The upper solvent layer was pipetteed into a new tube, and the solvent was removed by Genevac for 1 hour. The resulting residue was dissolved in 68 μL of MeOH and analyzed by LC / MS / MS instrumentation. Standards were prepared using the same method by extracting blood to which fentanyl in the concentration range of 5000 ng / mL to 1.6 ng / mL had been added. The detection limit was determined to be approximately 1.6 ng / mL. Figure 2A shows the results of experiments on the time course of blood fentanyl concentration in mice. Figure 2B shows the area under the fentanyl curve derived from the panel data in Figure 2A. Figure 2C shows the blood fentanyl concentrations in mice treated with JBZ-1, JBZ-2, and P2B5 at 15 minutes and 3 hours.

[0151] Example 5 In SCID mice (n=5-8 per group), cumulative drug response was tested 24 hours after IV injection of 25 mg / kg JBZ-1, primarily using supraspinal (hot plate) and spinal (tail flick) behavioral tests. In the hot plate test, mice were observed on an acrylic cylinder (14 cm diameter × 22 cm) on a 55°C surface. The waiting time for one of the following nociceptive responses—licking the hind leg, trembling / retracting the hind leg, or jumping—was measured with a 35-second cutoff to prevent tissue damage. Using an ITC Life Science Tail Flick Analgesia Meter, the tail immersion test was performed, measuring the time of tail retraction from a heated light (45% active intensity) with a 10-second cutoff to prevent tissue damage. Since tail flicking is a reflexive behavior, the hot plate test was always performed first. Immediately after both antinociceptive assays, fentanyl or carfentanil was administered by intraperitoneal injection. The fentanyl doses investigated were 0.2, 0.4, 0.6, and 0.8 mg / kg, and the carfentanil doses investigated were 0.01, 0.02, 0.04, 0.06, and 0.08 mg / kg, and complete dose-response curves were created. For control, more accurate ED was used. 50 To evaluate this, an additional mouse population (n=4) was administered relatively low doses (0.05, 0.1, 0.15, 0.2 mg / kg fentanyl, 0.005, 0.01, 0.015, and 0.02 mg / kg carfentanyl). The tests for all animals were repeated at 15-minute intervals, and after each injection, the cumulative dose was increased until complete antinociceptivity (exceeding the cutoff time) was observed in both assays. The maximum possible effect percentage (%MPE) was calculated from time using the following formula.

number

[0152] Example 6 JBZ-2, JBZ-3, JBZ-4, and P2B5 antibodies were evaluated using a fentanyl antinociceptive assay. mAbs (45 mg / kg) were administered intraperitoneally to four female Swiss Webster mice, and antinociceptiveness was induced by intraperitoneal fentanyl administration of 0.4 mg / kg four hours after mAb administration. Measurements were performed over 90 minutes, and the results are shown in Figure 4A. Antinociceptiveness was tracked for 15–115 minutes after fentanyl administration and the results are shown as averages in Figure 4B. Fentanyl antinociceptiveness was retested in the same mice two days after mAb administration, and the results are shown in Figure 4C.

[0153] The same mice from the antinociceptivity study were administered an IP fentanyl load (0.4 mg / kg), and blood was collected 20 minutes after drug injection. The results are shown in Figure 5A. The samples were made basic, combined with a deuterated internal standard, extracted with an organic solvent, and analyzed by LC-MS / MS using a standard curve to interpolate unknown concentrations. Blood samples collected two days after mAb administration, before drug administration, were analyzed by ELISA. The results are shown in Figure 5B.

[0154] Example 7 Rescue of fentanyl-induced antinociceptiveness by JBZ-4 and JBZ-7 injection was investigated. After intravenous administration of 0.2 mg / kg fentanyl, mice were tested using hot-plate (Figure 6A) and tail-flick (Figure 6B) antinociceptive assays at 15 minutes. Immediately afterward, 30 mg / kg antibody was administered intravenously, and the tests were restarted. JBZ-4 yielded superior results compared to JBZ-7.

[0155] Example 8 While antinociceptive assays are reliable indicators of opioid analgesia, respiratory models are more translationally related to opioid lethality. The antibodies disclosed herein, such as JBZ-4, block and relieve carfentanil-induced respiratory depression. Mice pretreated with 30 mg / kg JBZ-4 were administered 30 μg / kg IV carfentanil 48 hours later, and respiration was observed by whole-body plethysmography, expressed as minute ventilation (MV) normalized to the baseline. The results are shown in Figure 7A.

[0156] The efficacy of JBZ-4 was evaluated in a mouse model in which respiratory depression was induced by carfentanil, followed by rescue infusion of an antibody. The experimental protocol consisted of mice (n=12 per group) initially equilibrated using an EMKA whole-body plethysmography system until stable respiration was observed to function as a baseline reading. At time 0 min, administration of carfentanil (10 μg / kg, IV) resulted in a rapid decrease in respiration down to approximately 10% of the basal line ventilation (MV). At time 15 min, administration of JBZ-4 antibody (60 mg / kg, IV) or naloxone (1 mg / kg, IV) was followed by an immediate and steady increase in MV, achieving a statistically significant difference compared to the saline control group at 20 min. Naloxone showed a faster onset of action due to its rapid distribution as a small molecule, but the antibody showed a reversal in potency at later time points (Figure 7B).

[0157] Example 9 The X-ray crystal structure of the JBZ-4 antigen-binding fragment (Fab) complexed with fentanyl was revealed at a resolution of approximately 1.8 Å. From this structure, it can be seen that the drug:Fab ratio is 1:1 (or the drug:complete IgG ratio is 2:1), and the antigen-binding region at the tip of the Fab is formed between the heavy and light chains. This structure also exhibits a fentanyl binding mode, namely that the molecule is oriented so that the phenethyl tail faces "down" into the hydrophobic pocket of the paratope, the propanoyl group appears to be facing the solvent, and the anilide ring appears to be interlocked in a shallow pocket adjacent to the deeper phenethyl pocket.

[0158] Example 10 PK study. A non-GLP single-dose pharmacokinetic study of the monoclonal antibody (JBZ-4) was conducted. Nine adult male C. difficile rats were administered monoclonal antibody JBZ-4 (10 mL / kg) at doses of 10, 100, and 250 mg / kg by rapid intravenous (iv) administration. Blood samples for measuring serum JBZ-4 concentration were obtained from 3 rats / hour at 16 time points (0.083, 1, 4, 8, 24, 48, 72, 96, 144, 192, 240, 288, 336, 408, 504, and 672 hours after administration). Blood samples were processed to obtain serum, and JBZ-4 was analyzed using ELISA. Using group-mean serum concentration-time profiles and non-compartmental analysis (Phoenix WinNonlin, version 8.1, Certara, Princeton, NJ), the following PK parameters in rats were analyzed: area under the serum concentration-time curve, mean β-phase half-life (t1 / ). 2β ), C max , clearance (CL), and apparent distribution volume (V) at the end of life Z We estimated the following. The nominal dose administered to each treatment group was used for modeling.

[0159] Figure 9 shows the PK profiles of JBZ-4 in rats after single intravenous boras administration at 10, 25, and 250 mg / kg. The rats exhibited a dual exponential serum concentration-time profile with a short distribution phase followed by a long elimination phase. The half-life increased proportionally to the dose level.max Table 3 shows the AUC and volume of distribution (vz). At 10 mg / kg, the half-life is 102 hours. max The concentration was 805 μg / mL, the volume of distribution was 0.0196 L / kg, and the clearance value (CL) was 0.134 mL / hr / kg. At 100 mg / kg, the half-life was 171 hours. max The concentration was 4701 μg / mL, the volume of distribution was 0.0485, and the clearance value was 0.197 mL / hr / kg. At 250 mg / kg, the half-life was 308 hours. max The efflux concentration was 9228 μg / mL, the volume of distribution was 0.0766 L / kg, and the clearance value was 0.173 mL / hr / kg. The biphasic distribution of JBZ-4, which has a long efflux half-life, is characteristic of IgG monoclonal antibodies.

[0160] [Table 7]

[0161] Example 11 The plethysmography study in monkeys will be conducted in the same manner as described in Kishioka et al, "Buprenorphine and methoclocinnamox: agonist and antagonist effects on respiratory function in rhesus monkeys," European Journal of Pharmacology, 391:289-297 (2000), except that JBZ-4 will be used instead of buprenorphine or metoclocinnamox, and fentanyl or a fentanyl analog will be used instead of morphine or heroin. This study will evaluate the ability of JBZ-4 to antagonize the respiratory depressant effect of fentanyl. Specifically, monkeys will be pre-treated with intravenous or intramuscular injection of JBZ-4 at a dose of 1 mg / kg to 40 mg / kg. During the study period, monkeys will be administered an intramuscular cumulative dose of 0.0001 mg / kg to 0.01 mg / kg of fentanyl, followed immediately by 14 minutes of exposure to air, and then 6 minutes of exposure to 5% carbon dioxide. This cycle will be repeated 3 to 5 times. This trial yields opioid dose-response curves that shift to the right with JBZ-4 treatment. Dose-response curves obtained with non-fentanyl opioids such as oxycodone should not be affected by JBZ-4 treatment.

[0162] Section headings used herein are for structural purposes only and should not be construed as limiting the subject matter described herein. All documents or parts of documents referenced herein are expressly incorporated herein by reference, for any purpose whatsoever.

[0163] While various embodiments and aspects are shown and described herein, it will be apparent to those skilled in the art that such embodiments and aspects are provided merely as examples. Herein, many variations, modifications, and substitutions will be conceivable to those skilled in the art. A variety of alternatives to the embodiments and aspects described herein can be used.

[0164] Unofficial Sequence List The positions of CDR and FR in the sequences described herein are defined by the Kabat numbering system.

[0165] Sequence ID 1 = CDR-L1 SGDTLPKRSGY Sequence ID 2 = CDR-L2 KDTERPS Sequence ID 3 = CDR-L3 QSADSSFTYPS Sequence ID 4 = CDR-H1 SRNWWS Sequence ID 5 = CDR-H2 EVYHTGITNYNPSLKS Sequence ID 6 = CDR-H3 EVVGPTTGYFDL Sequence ID 7 = LFR1 SYELTQPPSVSVSPGQTARITC Sequence ID 8 = LFR2 WYQQKPDQAPLLVIN Sequence ID 9 = LFR3 GIPERFSGSKSGTTVTLTISGVQAEDEADYYC Sequence ID 10 = LFR4 FGGGTKLTVL Sequence ID 11 = HFR1 QVQLQESGPGLVKPSGTLSLTCTVSGGFIS Sequence ID 12 = HFR2 WVRQPPGKGLEWIG Sequence ID 13 = HFR3 RVTISVDKSKNQFSLKLSSVTAADTAVYYCAR Sequence ID 14 = HFR4 WGRGTLVTISS Sequence ID 15 = CDR-H1 GGFISSRN Sequence ID 16 = CDR-H2 YHTGI Sequence ID 17 = HFR1 QVQLQESGPGLVKPSGTLSLTCTVS Sequence ID 18 = HFR2 WWSWVRQPPGKGLEWIGEV Sequence ID 19 = HFR3 TNYNPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAR Sequence ID 20 = Light chain variable region. SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSKSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTVL Sequence ID 21 = Light chain steady region GQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 22 = Light chain amino acid sequence SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSKSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTV LGQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 23 = Heavy chain variable region. QVQLQESGPGLVKPSGTLSLTCTVSGGFISSRNWWSWVRQPPGKGLEWIGEVYHTGITNYNPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAREVVGPTTGYFDLWGRGTLVTISS SEQ ID NO:24=Heavy chain constant region ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGV EVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK Sequence ID 25 = Heavy chain amino acid sequence QVQLQESGPGLVKPSGTLSLTCTVSGGFISSRNWWSWVRQPPGKGLEWIGEVYHTGITNYNPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAREVVGPTTGYFDLWG RGTLVTISSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCD KTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEK TISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK Sequence ID 26 JBZ-2 light chain nucleic acid sequence TCCTATGAGCTGACCCAGCCACCCTCCGTGTCTGTGAGCCCAGGCCAGACCGCCAGGATCACATGTTCCGGCGATACACTGCCCAAGCGGAGCGGCTACTGGTATCAGCAGAAGCCAGACCAGGCCCCCCTGCTGGTCATCAACAAGGATACCGAGAGGCCTTCTGGCATCCCAGAGCGGTTCAGCGGCAGCAAGTCTGGCACCACAGTGACCCTGACAATCAGCGGAGTGCAGGCAGAGGACGAGGCAGATTACTATTGCCAGTCCGCCGACAGCTCCTTCACCTACCCAAGCTTTGGCGGCGGCACCAAGCTGACAGTGCTGGGTCAGCCCAAGGCTGCCCCCTCGGTCACTCTGTTCCCGCCCTCGAGTGAGGAGCTTCAAGCCAACAAGGCCACACTGGTGTGTCTCATAAGTGACTTCTACCCGGGAGCCGTGACAGTGGCCTGGAAGGCAGATAGCAGCCCCGTCAAGGCGGGAGTGGAGACCACCACACCCTCCAAACAAAGCAACAACAAGTACGCGGCCAGCAGCTACCTGAGCCTGACGCCTGAGCAGTGGAAGTCCCACAGAAGCTACAGCTGCCAGGTCACGCATGAAGGGAGCACCGTGGAGAAGACAGTGGCCCCTACAGAATGTTCA Sequence number 27 JBZ-2 light chain nucleic acid sequence TCCTATGAGCTGACCCAGCCACCCTCCGTGTCTGTGAGCCCAGGCCAGACCGCCAGGATCACATGTTCCGGCGATACACTGCCCAAGCGGAGCGGCTACTGGTATCAGCAGAAGCCAGACCAGGCCCCCCTGCTGGTCATCAACAAGGATACCGAGAGGCCTTCTGGCATCCCAGAGCGGTTCAGCGGCAGCAAATCTGGCACCACAGTGACCCTGACAATCAGCGGAGTGCAGGCAGAGGACGAGGCAGATTACTATTGCCAGTCCGCCGACAGCTCCTTCACCTACCCAAGCTTTGGCGGCGGCACCAAGCTGACAGTGCTGGGTCAGCCCAAGGCTGCCCCCTCGGTCACTCTGTTCCCGCCCTCGAGTGAGGAGCTTCAAGCCAACAAGGCCACACTGGTGTGTCTCATAAGTGACTTCTACCCGGGAGCCGTGACAGTGGCCTGGAAGGCAGATAGCAGCCCCGTCAAGGCGGGAGTGGAGACCACCACACCCTCCAAACAAAGCAACAACAAGTACGCGGCCAGCAGCTACCTGAGCCTGACGCCTGAGCAGTGGAAGTCCCACAGAAGCTACAGCTGCCAGGTCACGCATGAAGGGAGCACCGTGGAGAAGACAGTGGCCCCTACAGAATGTTCA Sequence number 28 JBZ-2 heavy chain nucleic acid sequence Sequence ID 29 Custom CDR-L3 xQSAxFTYPx Sequence ID 30 Custom CDR-L3 xQSADSSFTYPSx Sequence ID 31 Custom CDR-H1 GGFISSRNW Sequence ID 32: Custom CDR-H2 xWxExIxNx Sequence ID 33: Custom CDR-H2 xWxExITNx Sequence ID 34 Custom CDR-H3 xExVxGYFx Sequence ID 35 Custom CDR-H3 xExVGPxTGYFx Sequence ID 36 = LFR3JBZ-2 GIPERFSGSSSGTTVTLTISGVQAEDEADYYC Sequence ID 37 = Light chain variable region. JBZ-2 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSSSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTVL Sequence ID 38 = Light chain amino acid sequence. JBZ-2 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSSSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTV LGQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 39 = LFR3JBZ-6 GIPERFSGSNSGTTVTLTISGVQAEDEADYYC Sequence ID 40 = Light chain variable region. JBZ-6 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSNSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTVL Sequence ID 41 = Light chain amino acid sequence JBZ-6 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSNSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTV LGQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 42 = LFR3JBZ-5 GIPERFSGSTSGTTVTLTISGVQAEDEADYYC Sequence ID 43 = Light chain variable region. JBZ-5 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSTSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTVL Sequence ID 44 = Light chain amino acid sequence JBZ-5 SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSTSGTTVTLTISGVQAEDEADYYCQSADSSFTYPSFGGGTKLTV LGQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 45 JBZ-1 light chain amino acid sequence: SYELTQPPSVSVSPGQTARITCSGDTLPKRSGYWYQQKPDQAPLLVINKDTERPSGIPERFSGSSSGTTVTLTISGVQAEDEADYYCQSADSSFTYPMFGGGTKLTV LGQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS Sequence ID 46 JBZ-1 heavy chain amino acid sequence: QVQLQESGPGLVKPSGTLSLTCTVSGGFISSRNWWSWVRQPPGKGLEWIGEVYHTGITNYIPSLKSRVTISVDKSKNQFSLKLSSVTAADTAVYYCAREVVGPTTGYFDLWG RGTLVTISSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCD KTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEK TISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK Sequence ID 47 JBZ-1 light chain nucleic acid sequence: TCCTATGAGCTGACCCAGCCACCCTCCGTGTCTGTGAGCCCAGGCCAGACCGCCAGGATCACATGTTCCGGCGATACACTGCCCAAGCGGAGCGGCTACTGGTATCAGCAGAAGCCAGACCAGGCCCCCCTGCTGGTCATCAACAAGGATACCGAGAGGCCTTCTGGCATCCCAGAGCGGTTCAGCGGCAGCTCCTCTGGCACCACAGTGACCCTGACAATCAGCGGAGTGCAGGCAGAGGACGAGGCAGATTACTATTGCCAGTCCGCCGACAGCTCCTTCACCTACCCAATGTTTGGCGGCGGCACCAAGCTGACAGTGCTGGGTCAGCCCAAGGCTGCCCCCTCGGTCACTCTGTTCCCGCCCTCGAGTGAGGAGCTTCAAGCCAACAAGGCCACACTGGTGTGTCTCATAAGTGACTTCTACCCGGGAGCCGTGACAGTGGCCTGGAAGGCAGATAGCAGCCCCGTCAAGGCGGGAGTGGAGACCACCACACCCTCCAAACAAAGCAACAACAAGTACGCGGCCAGCAGCTACCTGAGCCTGACGCCTGAGCAGTGGAAGTCCCACAGAAGCTACAGCTGCCAGGTCACGCATGAAGGGAGCACCGTGGAGAAGACAGTGGCCCCTACAGAATGTTCA Sequence number 48 JBZ-1 heavy chain nucleic acid sequence:

Claims

1. An antibody capable of binding to fentanyl, carfentanyl, 3-methylfentanyl, acetylfentanyl, α-methylfentanyl, butyrylfentanyl, or para-tolylfentanyl, wherein the antibody is (i) Light chain variable region including CDR L1 as described in Sequence ID No. 1, CDR L2 as described in Sequence ID No. 2, and CDR L3 as described in Sequence ID No. 3; and (ii) A heavy chain variable region including CDR H1 described in SEQ ID NO: 4, CDR H2 described in SEQ ID NO: 5, and CDR H3 described in SEQ ID NO: 6, antibody.

2. (a) A light chain framework region comprising LFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 7, LFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 8, LFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 9, and LFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 10, and (b) A heavy chain framework region comprising HFR1 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 11; HFR2 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 12; HFR3 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO: 13; and HFR4 having an amino acid sequence having at least 95% sequence identity with SEQ ID NO:

14. The antibody according to claim 1.

3. (a) A light chain framework region including LFR1 described in SEQ ID NO: 7, LFR2 described in SEQ ID NO: 8, LFR3 described in SEQ ID NO: 9, and LFR4 described in SEQ ID NO: 10, (b) The antibody according to claim 1, further comprising a heavy chain framework region comprising HFR1 as described in SEQ ID NO: 11; HFR2 as described in SEQ ID NO: 12; HFR3 as described in SEQ ID NO: 13; and HFR4 as described in SEQ ID NO:

14.

4. The antibody according to claim 1, wherein the light chain variable region has at least 90% sequence identity with SEQ ID NO: 20, and the heavy chain variable region has at least 90% sequence identity with SEQ ID NO:

23.

5. The antibody according to claim 4, wherein the light chain variable region includes SEQ ID NO: 20 and the heavy chain variable region includes SEQ ID NO:

23.

6. The antibody according to any one of claims 1 to 5, wherein the antibody is a single-stranded variable fragment.

7. The antibody according to any one of claims 1 to 5, further comprising a light chain constant region having an amino acid sequence that is at least 90% identical to SEQ ID NO: 21, and a heavy chain constant region having at least 90% identical to SEQ ID NO:

24.

8. The antibody according to claim 7, wherein the light chain constant region includes SEQ ID NO: 21, and the heavy chain constant region includes SEQ ID NO:

24.

9. The antibody according to any one of claims 1 to 8, wherein the antibody is an IgG1 antibody.

10. The antibody is a Fab' fragment or F(ab)' ２ A fragment of the antibody according to any one of claims 1 to 5 and 7 to 9.

11. The antibody according to any one of claims 1 to 10, wherein the antibody is a humanized monoclonal antibody.

12. A pharmaceutical composition comprising the antibody according to any one of claims 1 to 11 and a pharmaceutically acceptable excipient.

13. A pharmaceutical composition comprising an antibody according to any one of claims 1 to 11, for the treatment or prevention of opioid overdose in a patient, Here, the opioid is fentanyl, carfentanyl, 3-methylfentanyl, acetylfentanyl, α-methylfentanyl, butyrylfentanyl, or p-tolylfentanyl. Pharmaceutical composition.

14. A pharmaceutical composition comprising an antibody according to any one of claims 1 to 11, for the treatment or prevention of opioid-induced respiratory depression in a patient, Here, the opioid is fentanyl, carfentanyl, 3-methylfentanyl, acetylfentanyl, α-methylfentanyl, butyrylfentanyl, or p-tolylfentanyl. Pharmaceutical composition.

15. A pharmaceutical composition comprising an antibody according to any one of claims 1 to 11, for the treatment of opioid use disorder in a patient, Here, the opioid is fentanyl, carfentanyl, 3-methylfentanyl, acetylfentanyl, α-methylfentanyl, butyrylfentanyl, or p-tolylfentanyl. Pharmaceutical composition.

16. The pharmaceutical composition according to any one of claims 13 to 15, wherein the opioid is fentanyl or carfentanyl.

17. An isolated nucleic acid encoding an antibody according to any one of claims 1 to 11.

18. A vector comprising a nucleic acid encoding an antibody according to any one of claims 1 to 11.

19. (i) the antibody according to any one of claims 1 to 11; and (ii) fentanyl, carfentanyl, 3-methylfentanyl, acetylfentanyl, α-methylfentanyl, butyrylfentanyl or para-tolylfentanyl A complex containing this.

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