The present invention relates to novel respiratory syncytial virus (RSV) F peptides and compositions comprising them. The present invention also relates to methods of evaluating anti-RSV antibody binding to F peptides. The present invention also relates to antibodies that immunospecifically bind to an F peptide of the present invention. The invention further provides methods and protocols for the administration of F peptides and/or antibodies that immunospecifically bind to F peptides for the prevention, neutralization, treatment of RSV infection. Additionally, the methods of the invention may be useful for the treatment, prevention and the amelioration of symptoms associated with RSV infection.

Description of the Invention

SUMMARY OF THE INVENTION

The present invention is based, in part, on the discovery of the RSV F protein epitope (alternatively, F protein epitope), that the antibody SYNAGIS.RTM. specifically binds. The F protein epitope comprises a 24 amino acid sequence: NSELLSLINDMPITNDQKKLMSNN (SEQ ID NO: 1) which competitively inhibits SYNAGIS.RTM. binding to the F-protein of RSV. One embodiment of the invention is a method of utilizing the F protein epitope and/or fragments, derivatives, and variants thereof (termed "F peptides") for generating (in-vivo, ex-vivo, or in-vitro) neutralizing antibodies (or other molecules that specifically bind the F protein epitopes or F peptides of the invention) against respiratory syncytial virus (RSV). Another embodiment of the invention is a method of administering a pharmaceutical composition comprising one or more F protein epitope and/or F peptides of the invention to a human in order to inhibit the binding of the RSV virus to its natural receptor and/or to be provided as a vaccine for preventing infection. Yet another embodiment of the invention relates to a method of treating upper respiratory tract infection caused by RSV in a patient/subject in need thereof comprising, intranasally administering an effective amount of a pharmaceutical composition of either the antibodies of the invention or the F peptides of the invention.

Another embodiment of the present invention is a method of screening for molecules including, but not limited to, antibodies, aptamers, small molecules (generally considered less than 10 kD in size), peptides (including fragments and derivatives of the foregoing) that specifically bind one or more F protein epitope or F peptides of the invention (collectively herein, "anti-F peptide binders" or "anti-F binders" or "anti-F peptide antibodies"). It is specifically contemplated that such screening methods would be used to identify molecules that neutralize RSV and/or prevent syncytia formation. In yet another embodiment, the F peptides are useful for the generation of binders, e.g., antibodies that specifically bind to an F peptide. Antibodies, fragments and derivatives thereof that specifically bind to an F protein epitope or F peptide are referred to herein as "anti-F protein antibodies or anti-F peptide antibodies", respectively.

The present invention encompasses, but is not limited to, recombinant, fully human, chimeric, mouse, CDR-grafted, and humanized anti-F protein antibodies or anti-F peptide antibodies and fragments and derivatives thereof, which are more fully described below.

F peptides of the invention are at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or at least 99%, or at least 99.5% identical to the F protein epitope of SEQ ID NO: 1.

The F protein epitopes and F peptides may be derived from the A antigenic region of the F protein (see FIG. 1 (see Original Patent)). As used herein, the term "derived" includes sequences similar but not identical to the sequence of the protein disclosed herein and to fragments sequences otherwise identical to the sequences of said protein. Also included are derivatives of the F protein epitope and/or F peptides including but not limited to, methylated, acetylated, carboxylated, glycosylated, and those containing non-natural amino acids.

It is another object of the present invention to provide F protein epitope and/or F peptides as heterologous polypeptide segments (e.g., as part of a fusion and/or chimeric molecule), or fragment, or portion thereof.

In one embodiment, the F protein epitopes and Fpeptides of the invention are recognized by the humanized antibody whose amino acid sequence is disclosed in Johnson et al., J. Infect. Dis. 176:1215-1224 (1997), including the modified humanized recombinant antibody referred to herein as SYNAGIS.RTM. (palivizumab).

In another embodiment, the F protein epitopes and F peptides of the invention are recognized by the humanized antibody whose amino acid sequence is disclosed in U.S. Pat. No. 6,818,216, including the modified humanized recombinant IgG1 antibody referred to herein as NUMAX.TM. (motavizumab) or MEDI-524.

In yet another embodiment, the F protein epitopes and F peptides of the invention are recognized by an anti-RSV antibody or fragment thereof that is not SYNAGIS.RTM. or NUMAX.TM. or the murine mAbs 47F and 7C2 (see, Arbiza J. et al., J. Gen. Virol., 73:2225-2234 (1992)).

While it is to be understood that the F protein epitopes and F peptides of the invention may bind to SYNAGIS.RTM. and/or NUMAX.TM. or the murine mAbs 47F and 7C2it is also to be understood that F protein epitopes and F peptides may bind to antibodies or fragments thereof, other than SYNAGIS.RTM. or NUMAX.TM. or the murine mAbs 47F and 7C2See, examples in U.S. Pat. No. 5,762,905; U.S. Pat. No. 5,811,534; U.S Patent Publication 2003/0091584; Beeler et al. (1989, J. Virol 63: 2941); and Palomo et al., 1990, J. Virol 64: 4199) each of which are incorporated herein by reference. The skilled artisan will further appreciate that the F protein epitopes and F peptides may bind to chimeric, humanized, fully human, CDR-grafted, and other derivatives of an antibody other than SYNAGIS.RTM. or NUMAX.TM. that immunospecifically binds to an F protein epitope and/or F peptide.

It is a further object of the present invention to provide an pharmaceutical composition comprising at least one F protein epitope and/or F peptide binder, wherein said binder is suspended in a pharmacologically acceptable carrier. Acceptable pharmaceutical carriers include but are not limited to non-toxic buffers, fillers, isotonic solutions, etc. Additionally, vaccines, or vaccine compositions, comprising said peptide are contemplated as an embodiment of the invention.

It is a still further object of the present invention to provide a process for preventing or treating an RSV infection comprising administering to a patient in need of such prevention or treatment, a therapeutically, or prophylactically, effective amount of a vaccine composition comprising the immunogenic composition described above.

It is a further object of the present invention to provide an immunogenic composition comprising at least one F protein epitope and/or F peptide of the invention wherein said peptide is suspended in a pharmacologically acceptable carrier. Acceptable pharmaceutical carriers include but are not limited to non-toxic buffers, fillers, isotonic solutions, etc. Additionally, vaccines, or vaccine compositions, comprising said peptide are contemplated as an embodiment of the invention.

The present invention provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with RSV infection in a subject comprising administering to said subject one or more of the F protein epitope and/or F peptides of the invention or fragments thereof. It is further contemplated that such administration be either intranasal or inhaled (pulmonary).

The present invention also provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with RSV infection in a subject comprising administering to said subject one or more of the anti-RSV antibodies or fragments thereof obtained by using the F protein epitopes or F peptides of the invention or fragments thereof. It is also contemplated that the present invention also provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with RSV infection in a subject comprising administering to said subject one or more of the anti-RSV antibodies or fragments thereof obtained by using the F protein epitopes or F peptides of the invention or fragments thereof, wherein the anti-RSV antibodies or fragments thereof are not SYNAGIS.RTM. or NUMAX.TM. or murine mAbs 47F and 7C2 (see, Arbiza J. et al., J. Gen. Virol., 73:2225-2234 (1992)). It is further contemplated that such administration be either intranasal or inhaled (pulmonary).

The invention encompasses sustained release formulations for the administration of one or more of the F protein epitopes or F peptides and fragments thereof. The sustained release formulations reduce the dosage and/or frequency of administration of said peptides to a subject. Further, the sustained release formulations may be administered to maintain a therapeutically or prophylactically effective serum titer which does not exceed a certain maximum serum titer for a certain period of time.

The invention encompasses sustained release formulations for the administration of one or more anti-F peptide or F protein epitope binders (e.g., antibodies or fragments thereof) wherein the anti-RSV antibodies or fragments thereof are not SYNAGIS.RTM. or NUMAX.TM. or murine mAbs 47F and 7C2 (see, Arbiza J. et al., J. Gen. Virol., 73:2225-2234 (1992)). The sustained release formulations of the invention reduce the dosage and/or frequency of administration of said binders to a subject. Further, the sustained release formulations may be administered to maintain a therapeutically or prophylactically effective serum levels (e.g., titer) which does not exceed a certain maximum serum titer for a certain period of time.

The present invention encompasses methods of administering an F protein epitope or Fpeptide of the invention and/or anti-F protein epitope or F peptide binders (e.g., antibodies) directly to the site of RSV infection. In particular, the invention encompasses pulmonary or intranasal delivery of at least one F protein epitope or F peptide of the invention and/or one or more anti-F protein epitope or F peptide binder (e.g., antibodies). As an example, pulmonary administration can be employed, e.g., by use of an inhaler or nebulizer, and formulation with an aerosolizing agent. See, e.g., U.S. Pat. Nos. 6,019,968, 5,985,320, 5,985,309, 5,934,272, 5,874,064, 5,855,913, 5,290,540, and 4,880,078; and PCT Publication Nos. WO 92/19244, WO 97/32572, WO 97/44013, WO 98/31346, and WO 99/66903, each of which is incorporated herein by reference their entirety. In one embodiment, an antibody of the invention or fragment thereof, or composition of the invention is administered using Alkermes AIR..TM.. pulmonary drug delivery technology (Alkermes, Inc., Cambridge, Mass.). Alternatively, methods of administering an antibody or fragment thereof, or pharmaceutical composition include, but are not limited to, parenteral administration (e.g., intradermal, intramuscular, intraperitoneal, intravenous and subcutaneous), epidural, and mucosal (e.g., intranasal and oral routes). In one embodiment, antibodies of the present invention or fragments thereof, or pharmaceutical compositions are administered intramuscularly, intravenously, or subcutaneously. The compositions may be administered by any convenient route, for example by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (e.g., oral mucosa, rectal and intestinal mucosa, etc.) and may be administered together with other biologically active agents. Administration can be systemic or local.

The present invention also provides antibodies or fragments thereof that immunospecifically bind the F protein epitope of SEQ ID NO:1 and/or an 80% identical F peptide variant thereof and have an association rate constant or k.sub.on rate (antibody (Ab)+antigen (Ag) Ab-Ag) of at least 10.sup.5 M.sup.-1 s.sup.-1, at least 5.times.10.sup.5 M.sup.-1 s.sup.-1, at least 10.sup.6 M.sup.-1 s.sup.-1, at least 5.times.10.sup.6 M.sup.-1 s.sup.-1, at least 10.sup.7 M.sup.-1 s.sup.-1, at least 5.times.10.sup.7 M.sup.-1 s.sup.-1, or at least 10.sup.8 M.sup.-1 s.sup.-1 as assessed using an assay described herein or known to one of skill in the art (e.g., a BIAcore assay)

The present invention provides antibodies or fragments thereof that specifically bind the F protein epitope of SEQ ID NO: 1 and/or an 80% identical F peptide variant thereof and have a k.sub.off rate (antibody (Ab)+antigen (Ag) Ab-Ag) of less than 10.sup.-1 s.sup.-1, less than 5.times.10.sup.-1 s.sup.-1, less than 10.sup.-2 s.sup.-1, less than 5.times.10.sup.-2 s.sup.-1, less than 10.sup.-3 s.sup.-1, less than 5.times.10.sup.-3 s.sup.-1, less than 10.sup.-4 s.sup.-1, less than 5.times.10.sup.-4 s.sup.-1, less than 10.sup.-5 s.sup.-1, less than 5.times.10.sup.-5 s.sup.-1, less than 10.sup.-6 s.sup.-1, less than 5.times.10.sup.-6 s.sup.-1, less than 10.sup.-7 s.sup.-1, less than 5.times.10.sup.-7 s.sup.-1, less than 10.sup.-8 s.sup.-1, less than 5.times.10.sup.-8 s.sup.-1, less than 10.sup.-9 s.sup.-1, less than 5.times.10.sup.-9 s.sup.-1, or less than 10.sup.-10 s.sup.-1 as assessed using an assay described herein or known to one of skill in the art (e.g., a BIAcore assay)

The present invention also provides antibodies or fragments thereof that specifically bind the F protein epitope of SEQ ID NO:1 and/or an 80% identical F peptide variant thereof and have an affinity constant or K.sub.a (k.sub.on/k.sub.off) of at least 10.sup.2 M.sup.-1, at least 5.times.10.sup.2 M.sup.-1, at least 10.sup.3 M.sup.-1, at least 5.times.10.sup.3M.sup.-1, at least 10.sup.4 M.sup.-1, at least 5.times.10.sup.4 M.sup.-1, at least 10.sup.5 M.sup.-1, at least 5.times.10.sup.5 M.sup.-1, at least 10.sup.6 M.sup.-1, at least 5.times.10.sup.6 M.sup.-1, at least 10.sup.7 M.sup.-1, at least 5.times.10.sup.7 M.sup.-1, at least 10.sup.8 M.sup.-1, at least 5.times.10.sup.8 M.sup.-1, at least 10.sup.9 M.sup.-1, at least 5.times.10.sup.9 M.sup.-1, at least 10.sup.10 M.sup.-1, at least 5.times.10.sup.10 M.sup.-1, at least 10.sup.11 M.sup.-1, at least 5.times.10.sup.12 M.sup.-1, at least 10.sup.12M.sup.-1, at least 5.times.10.sup.12 M.sup.-1, at least 10.sup.13 M.sup.-1, at least 5.times.10.sup.13 M.sup.-1, at least 10.sup.14 M.sup.-1, at least 5.times.10.sup.14 M.sup.-1, at least 10.sup.15 M.sup.-1, or at least 5.times.10.sup.15 M.sup.-1 as assessed using an assay described herein or known to one of skill in the art (e.g., a BIAcore assay).

In one embodiment, the invention provides methods for preventing, treating, or managing an RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of at least one anti-F protein epitope or F peptide binder (e.g., antibodies or fragments thereof). In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%.

In another embodiment, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of at least one F protein epitope or F peptide of the invention. In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%. In one embodiment, the F peptide mimics the F protein and binds to the natural receptor on host's cells and thus prevents RSV infection.

In one embodiment, the F peptides of the invention are at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or at least 99%, or at least 99.5% identical to an F protein epitope of the RSV virus that causes the infection in the subject. In another embodiment, a derivative of an F peptide of the invention can be used to prevent viral fusion. Such derivatives include, but are not limited to, F peptides that have been modified (e.g., methylated, acetylated, carboxylated, glycosylated), substituted with non native amino acids, truncated so that stretches of amino acids are removed, or lengthened, so that single amino acids or stretches thereof have been added. In yet another embodiment, the F peptides are used to treat, manage, or prevent RSV infection. In still another embodiment, a combination of F peptides are administered to treat, manage, or prevent RSV infection.

DETAILED DESCIPTION OF THE INVENTION

The present invention provides F protein epitopes and F peptides that bind SYNAGIS.RTM. and/or NUMAX.TM.. In one embodiment, F protein epitopes and/or F peptides competitively inhibit the binding of SYNAGIS.RTM. and/or NUMAX.TM. to RSV F protein. NUMAX.TM.. In a specific embodiment, one or more F protein epitopes and/or F peptides will be administered to a mammal as a vaccine or antigenic formulation to create an immune response to protect said mammal from an RSV infection. In another embodiment, one or more F protein epitopes and/or F peptides will be administered to a mammal to prevent RSV infection by passive immunization. Without being bound by any particular theory or mechanism, it is contemplated that the F protein epitopes and/or F peptides may bind to the natural receptor of the RSV F protein and block binding thereby preventing F protein mediated fusion of RSV with the cell.

The present invention also provides molecules, e.g., antibodies that specifically bind to one or more F protein epitopes and/or F peptides (e.g., anti-F protein epitope antibodies and/or anti-F peptide antibodies). It is contemplated that said antibodies are not Synagis.RTM. (palivizumab) or Numax.TM. (motavizumab) or murine mAbs 47F and 7C2 (see, Arbiza J. et al., J. Gen. Virol., 73:2225-2234 (1992)). The present invention additionally provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with a RSV infection in a subject comprising administering to said subject one or more said anti-F protein epitope binders and/or anti-F peptide binders, e.g., antibodies which may then will neutralize an RSV virus. In one embodiment, anti-F protein epitope antibodies or F peptide antibodies have a high affinity and/or high avidity and/or have a serum half-life that has been optimized. The high affinity and/or high avidity of said antibodies of the invention enable the use of lower doses of said antibodies than previously thought to be effective for the prevention, neutralization, treatment and the amelioration of symptoms associated with RSV infection. The use of lower doses of antibodies which specifically bind to one or more RSV antigens (e.g., F protein epitopes and/or F peptides), reduces the likelihood of adverse effects, as well as providing a more effective prophylaxis. Further, the high affinity and/or high avidity of an anti-F protein epitope antibody or an anti-F peptide antibody of the invention enable less frequent administration of said antibodies than previously thought to be necessary for the prevention, neutralization, treatment and the amelioration of symptoms associated with RSV infection.

The present invention also provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with a RSV infection in a subject comprising administering to said subject one or more anti-F protein epitope binders and/or anti-F peptide binders, e.g., antibodies, said binders having a longer half-life in vivo than other previously known binders. In particular, the present invention provides for said antibodies which have a half-life in a subject, preferably a mammal and most preferably a human, of greater than 3 days, greater than 7 days, greater than 10 days, preferably greater than 15 days, greater than 25 days, greater than 30 days, greater than 35 days, greater than 40 days, greater than 45 days, greater than 2 months, greater than 3 months, greater than 4 months, or greater than 5 months. To prolong the serum circulation of antibodies (e.g., monoclonal antibodies, single chain antibodies and Fab fragments) in vivo, for example, inert polymer molecules such as high molecular weight polyethyleneglycol (PEG) can be attached to the antibodies with or without a multifunctional linker either through site-specific conjugation of the PEG to the N- or C-terminus of the antibodies or via epsilon-amino groups present on lysine residues. Linear or branched polymer derivatization that results in minimal loss of biological activity will be used. The degree of conjugation can be closely monitored by SDS-PAGE and mass spectrometry to ensure proper conjugation of PEG molecules to the antibodies. Unreacted PEG can be separated from antibody-PEG conjugates by size-exclusion or by ion-exchange chromatography. PEG-derivatized antibodies can be tested for binding activity as well as for in vivo efficacy using methods well-known to those of skill in the art, for example, by immunoassays described herein. Antibodies having an increased half-life in vivo can also be generated by introducing one or more amino acid modifications (i.e., substitutions, insertions or deletions) into an IgG constant domain, or FcRn binding fragment thereof (preferably a Fc or hinge-Fc domain fragment). See, e.g., International Publication Nos. WO 02/06919; WO 98/23289; and WO 97/34631; and U.S. Pat. No. 6,277,375; each of which is incorporated herein by reference in its entirety. Such half life extension can also be achieved by conjugation to albumin. The techniques are well-known in the art, see, e.g., International Publication Nos. WO 93/15199, WO 93/15200, and WO 01/77137; and European Patent No. EP 413,622, all of which are incorporated herein by reference.

The present invention also provides methods of preventing, neutralizing, treating and ameliorating one or more symptoms associated with a RSV infection in a subject comprising administering to said subject one or more F protein epitope and/or F peptides of the invention as a vaccine or antigenic formulation to generate an immune response to protect said subject from an RSV infection. The present invention also provides for methods of administering the F protein epitope and/or F peptide as a passive immunization therapy to prevent RSV infections.

The present invention further provides methods of administering to a subject one or more anti-F peptide binders. The present invention encompasses methods of delivering one or more anti-F peptide binders, wherein said binder is capable of neutralizing RSV. In particular, the invention encompasses pulmonary delivery of one or more F peptides of the invention and/or one or more anti-F peptide binders. In particular, the invention encompasses pulmonary or intranasal delivery of at least one F protein epitope or F peptide of the invention and/or one or more anti-F protein epitope or F peptide binder (e.g., antibodies). As an example, pulmonary administration can be employed, e.g., by use of an inhaler or nebulizer, and formulation with an aerosolizing agent. See, e.g., U.S. Pat. Nos. 6,019,968, 5,985,320, 5,985,309, 5,934,272, 5,874,064, 5,855,913, 5,290,540, and 4,880,078; and PCT Publication Nos. WO 92/19244, WO 97/32572, WO 97/44013, WO 98/31346, and WO 99/66903, each of which is incorporated herein by reference their entirety. In one embodiment, an antibody of the invention or fragment thereof, or composition of the invention is administered using Alkermes AIR..TM.. pulmonary drug delivery technology (Alkermes, Inc., Cambridge, Mass.). Alternatively, methods of administering an antibody or fragment thereof, or pharmaceutical composition include, but are not limited to, parenteral administration (e.g., intradermal, intramuscular, intraperitoneal, intravenous and subcutaneous), epidural, and mucosal (e.g., intranasal and oral routes). In one embodiment, antibodies of the present invention or fragments thereof, or pharmaceutical compositions are administered intramuscularly, intravenously, or subcutaneously. The compositions may be administered by any convenient route, for example by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (e.g., oral mucosa, rectal and intestinal mucosa, etc.) and may be administered together with other biologically active agents. Administration can be systemic or local.

The present invention provides methods of achieving or inducing a serum titer of at least 1 .mu.g/ml, or at least 2 .mu.g/ml, or at least 5 .mu.g/ml, or at least 6 .mu.g/ml, or at least 10 .mu.g/ml, or at least 15 .mu.g/ml, or at least 20 .mu.g/ml, or at least 25 .mu.g/ml, or at least 30 .mu.g/ml, or at least 40 .mu.g/ml, or at least 50 .mu.g/ml, or at least 75 .mu.g/ml, or at least 100 .mu.g/ml, or at least 125 .mu.g/ml, or at least 150 .mu.g/ml, or at least 175 .mu.g/ml, or at least 200 .mu.g/ml, or at least 225 .mu.g/ml, or at least 250 .mu.g/ml, or at least 275 .mu.g/ml, or at least 300 .mu.g/ml, or at least 325 .mu.g/ml, or at least 350 .mu.g/ml, or at least 375 .mu.g/ml, or at least 400 .mu.g/ml of an anti-F protein epitope antibody and/or anti-F peptide antibody, or fragment thereof, while reducing or avoiding adverse affects. Preferably the serum titers are achieved approximately 30 days after administration of a first dose of such an antibody (or an F protein epitope and/or F peptide of the invention) and without administration of any other doses of said antibodies or fragments thereof.

In a specific embodiment, a serum titer in a non-primate mammal of at least 40 .mu.g/ml, preferably at least 80 .mu.g/ml, or at least 100 .mu.g/ml, or at least 120 .mu.g/ml, or at least 150 .mu.g/ml, or at least 200 .mu.g/ml, or at least 250 .mu.g/ml, or at least 300 .mu.g/ml, of one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies is achieved at least 1 day after administering a dose of less than 2.5 mg/kg, preferably less than 1 mg/kg, or less than 0.5 mg/kg of the anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof to the non-primate mammal.

In another embodiment, a serum titer in a non-primate mammal of at least 150 .mu.g/ml, preferably at least 200 .mu.g/ml, or at least 250 .mu.g/ml, or at least 300 .mu.g/ml, or at least 350 .mu.g/ml, or at least 400 .mu.g/ml of one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies, or fragments thereof, is achieved at least 1 day after administering a dose of approximately 5 mg/kg of the anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof to the non-primate mammal.

In another embodiment, a serum titer in a primate of at least 40 .mu.g/ml, preferably at least 80 .mu.g/ml, or at least 100 .mu.g/ml, or at least 120 .mu.g/ml, or at least 150 .mu.g/ml, or at least 200. .mu.g/ml, or at least 250 .mu.g/ml, or at least 300 .mu.g/ml of one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof is achieved at least 30 days after administering a first dose of less than 5 mg/kg, preferably less than 3 mg/kg, or less than 1 mg/kg, or less than 0.5 mg/kg of the anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof to the primate.

In yet another embodiment, a serum titer in a primate of at least 200 .mu.g/ml, or at least 250 .mu.g/ml, or at least 300 .mu.g/ml, or at least 350 .mu.g/ml, or at least 400 .mu.g/ml of one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof is achieved at least 30 days after administering a first dose of approximately 15 mg/kg of the antibodies or fragments thereof to the primate. In accordance with these embodiments, the primate is preferably a human.

The present invention provides methods for preventing, treating, or ameliorating one or more symptoms associated with a RSV infection in a mammal, preferably a human, said methods comprising administering a dose to said mammal of a prophylactically or therapeutically effective amount of one or more F protein epitope and/or F peptide of the invention and/or anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof.

The present invention provides methods for preventing, treating, or ameliorating one or more symptoms associated with a RSV infection in a mammal, preferably a human, said methods comprising administering a first dose into a mammal of a prophylactically or therapeutically effective amount of one or more F protein epitope and/or F peptide of the invention and then a second dose of one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies, or fragments thereof. In another embodiment the present invention provides methods for preventing, treating, or ameliorating one or more symptoms associated with a RSV infection in into a mammal, preferably a human, said methods comprising administering a first dose into a mammal of a prophylactically or therapeutically effective amount one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof then a second dose of one or more F protein epitope and/or F peptides of the invention. In another embodiment the present invention provides methods for preventing, treating, or ameliorating one or more symptoms associated with a RSV infection in a mammal, preferably a human, said methods comprising administering a concurrent dosing into a mammal of a prophylactically or therapeutically effective amount one or more anti-F protein epitope antibodies and/or anti-F peptide antibodies or fragments thereof and one or more F protein epitope and/or F peptides of the invention. It is specifically contemplated that any of the above methods may also encompass the administration of antibodies that immunospecifically bind to an RSV epitope that is not the F protein epitope and/or F peptide of the invention.

In certain embodiments, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of one or more F protein epitope and/or F peptides of the invention. In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%. In a specific embodiment, an F peptide mimics the F protein and binds to the natural receptor on host's cells and thus prevents RSV infection.

In other embodiments, an F peptide of the invention is at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99%, or at least 99.5% identical to the peptide of the virus that causes the infection in the subject. In certain embodiments, a derivative of an F peptide of the invention can be used to prevent viral fusion. Such derivatives include, but are not limited to, peptides that have been substituted with non-native amino acids, truncated so that stretches of amino acids are removed, or lengthened, so that single amino acids or stretches thereof have been added. In yet another embodiment, an F peptide of the invention is used to treat, manage, or prevent RSV infection. In an even further embodiment, a combination of the above-described F peptides is administered to treat, manage, or prevent RSV infection.

In certain embodiments, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of one or more anti-F peptide binders. In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%.

In other specific embodiments, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of one or more anti-F peptide antibodies. In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%.

Peptides of the Invention

In one embodiment of the invention, an F peptide of the invention or fragment thereof or pharmaceutical composition comprising said F peptide, is administered to a subject to treat, manage, or prevent RSV infection. In a preferred embodiment, said subject is a human. In a specific embodiment, the F peptide or fragment thereof or pharmaceutical composition comprising said F peptide is a vaccine or an immunogenic composition. Another embodiment includes the administration of an F peptide or fragment thereof or pharmaceutical composition comprising said F peptide as a passive immunotherapy. In certain embodiments, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the methods comprising administering a pharmaceutically effective amount of one or more F peptide of the invention. In other embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%.

In certain embodiments, an F peptide of the invention is at least or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99%, or at least 99.5% identical to SEQ ID NO.: 1. The invention further provides polynucleotides comprising a nucleotide sequence encoding F peptide peptides of the invention.

In certain embodiments, a derivative of an F peptide of the invention can be used to prevent viral fusion. Such derivatives include, but are not limited to, peptides that have been substituted with non-native amino acids, truncated so that stretches of amino acids are removed, or lengthened so that single amino acids or stretches thereof have been added. The invention also encompasses any variants of an F peptide. Variants include but are not limited to substitution and/or by addition and/or deletion of one or more amino acids, provided that this modification does not impair the antigenic, immunogenic properties or binding capabilities of the polypeptide.

It is specifically contemplated that conservative amino acid substitutions may be made in an F peptide. It is well known in the art that "conservative amino acid substitution" refers to amino acid substitutions that substitute functionally equivalent amino acids. Conservative amino acid changes result in silent changes in the amino acid sequence of the resulting peptide. For example, one or more amino acids of a similar polarity act as functional equivalents and result in a silent alteration within the amino acid sequence of the peptide. Substitutions that are charge neutral and which replace a residue with a smaller residue may also be considered "conservative substitutions" even if the residues are in different groups (e.g., replacement of phenylalanine with the smaller isoleucine). Families of amino acid residues having similar side chains have been defined in the art. Several families of conservative amino acid substitutions are shown in Table 2 (see Original Patent).

The term "conservative amino acid substitution" also refers to the use of amino acid analogs or variants. Guidance concerning how to make phenotypically silent amino acid substitutions is provided in Bowie et al., "Deciphering the Message in Protein Sequences: Tolerance to Amino Acid Substitutions," (1990, Science 247:1306-1310), incorporated herein by reference.

In other embodiments, variants of an F peptide are generated to improve certain characteristics including but not limited to, solubility, stability, pI, and serum half-life. For example, peptide variants containing amino acid substitutions of charged amino acids with other charged or neutral amino acids may produce proteins with improved characteristics, such as less aggregation. Aggregation of pharmaceutical formulations both reduces activity and increases clearance due to the aggregate's immunogenic activity. See Pinckard et al., Clin. Exp. Immunol. 2:331-340 (1967); Robbins et al., Diabetes 36: 838-845 (1987); Cleland et al., Crit. Rev. Therapeutic Drug Carrier Systems 10:307-377 (1993), each of which are incorporated herein by reference.

In a preferred embodiment, an F peptide of the invention is used to treat, manage, or prevent RSV infection. In another preferred embodiment, a combination of F peptides is administered to treat, manage, or prevent RSV infection. In still another preferred embodiment, a combination of one or more F peptides and/or one more anti-F peptide antibodies is administered to treat, manage, or prevent RSV infection. In a specific embodiment, doses of individual components are administered sequentially. In another specific embodiment, doses of individual components are administered concurrently.

Generation of an F Peptide

F peptides can be generated by numerous means including but not limited to, chemical synthesis and recombinant protein expression. Soluble peptides can be expressed and purified from a host cell. In one embodiment, synthetic recombinant DNAs are prepared that encode an F peptide of the invention.

In another embodiment, synthetic recombinant DNAs are prepared that additionally contain sequence tags useful in facilitating purification of an F peptide. In a preferred embodiment of the invention, the tag that facilitates purification of the F peptide does not interfere with its activity. In a specific embodiment, the tag amino acid sequence is a hexa-histidine peptide, such as the tag provided in a pQE vector (QIAGEN, Inc., 9259 Eton Avenue, Chatsworth, Calif., 91311). Other peptide tags useful for purification include, but are not limited to, the hemagglutinin "HA" tag, which corresponds to an epitope derived from the influenza hemagglutinin protein (Wilson et al., 1984, Cell 37:767) and the "flag" tag.

There are a number of different approaches that can be used to express and purify soluble peptides. The DNA sequence of an F peptide may be manipulated using methods well known in the art for the manipulation of nucleotide sequences, e.g., recombinant DNA techniques, (see, for example, the techniques described in Current Protocols in Molecular Biology, F. M. Ausubel et al., ed., John Wiley & Sons (Chichester, England, 1998); Molecular Cloning: A Laboratory Manual, 3nd Edition, J. Sambrook et al., ed., Cold Spring Harbor Laboratory Press (Cold Spring Harbor, N.Y., 2001), each of which are incorporated herein by reference). DNA vectors encoding an F peptide are prepared and subsequently transformed into an appropriate expression host cell, such as, e.g., E. coli strain BL21 (DE3), and the protein is expressed and purified using methods routine in the art. For example, expression of a gene encoding the peptide with a histidine tag can be induced from a pET vector using IPTG. Cells can then be lysed and the expressed peptide can be isolated after immobilization on a Ni-chelated Sepharose affinity column following elution with a counter charged species, for e.g., imidazole.

The invention also specifically encompasses fusion proteins comprising an F peptide. Polypeptides, proteins and fusion proteins can be produced by standard recombinant DNA techniques or by protein synthetic techniques, e.g., by use of a peptide synthesizer. For example, a nucleic acid molecule encoding a peptide, polypeptide, protein or a fusion protein can be synthesized by conventional techniques including automated DNA synthesizers. Alternatively, PCR amplification of gene fragments can be carried out using anchor primers which give rise to complementary overhangs between two consecutive gene fragments which can subsequently be annealed and reamplified to generate a chimeric gene sequence (see, e.g., Current Protocols in Molecular Biology, Ausubel et al., eds., John Wiley & Sons, 1992). Moreover, a nucleic acid encoding a bioactive molecule can be cloned into an expression vector containing an F peptide such that the bioactive molecule is linked in-frame to the F protein epitope.

F protein epitopes according to the invention may be purified and isolated by methods known in the art. In particular, having identified the gene sequence, it will be possible to use recombinant techniques to express the genes in a suitable host. In addition, the peptides may be synthesized synthetically. Active fragments and related molecules can be identified and may be useful in therapy. For example, the peptides or their active fragments may be used as antigenic determinants in a vaccine, to elicit an immune response. They may also be used in the preparation of antibodies, for passive immunization, or diagnostic applications. Suitable antibodies include monoclonal antibodies, or fragments thereof, including single chain Fv fragments. Humanized antibodies are also within the scope of the invention. Methods for the preparation of antibodies will be apparent to those skilled in the art and are reviewed below.

The F protein epitopes of the invention can be coupled with a carrier that enhances isotonicity and chemical stability. Such materials are non-toxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, succinate, acetic acid, and other organic acids or their salts; antioxidants such as ascorbic acid; low molecular weight (less than about ten residues) polypeptides, e.g., polyarginine or tripeptides; proteins, such as serum albumin or bovine serum albumin (BSA), gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids, such as glycine, glutamic acid, aspartic acid, or arginine, or ornithine, or cysteine; monosaccharides, disaccharides, and other carbohydrates including cellulose or its derivatives, glucose, manose, or dextrins; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol; counterions such as sodium; and/or nonionic surfactants such as polysorbates, poloxamers, or PEG.

The present invention encompasses a fusion of an F peptide with another compound, such as a compound to increase the stability and/or solubility of the polypeptide (for example, polyethylene glycol), fusion of the peptide with additional amino acids, such as, for example, an IgG Fc fusion region peptide, serum albumin (preferably human serum albumin) or a fragment thereof, or leader or secretory sequence, or a sequence facilitating purification, or fusion of the peptide with another compound, such as albumin (including but not limited to recombinant albumin (see, e.g., U.S. Pat. No. 5,876,969, issued Mar. 2, 1999, EP Patent 0 413 622, and U.S. Pat. No. 5,766,883, issued Jun. 16, 1998, herein incorporated by reference in their entirety). Such variant peptides are deemed to be within the scope of those skilled in the art from the teachings herein.

Antibodies and Other Binders

It should be recognized that antibodies that specifically bind the F peptide are known in the art. For example, SYNAGIS.RTM. is a humanized monoclonal antibody presently used for the prevention of RSV infection in pediatric patients.

The invention encompasses novel antibodies, fragments and other biological or macromolecules which specifically bind to an F protein epitope of the invention (e.g., anti-F peptide antibodies). In certain embodiments, the invention provides methods for preventing, treating, or managing a RSV infection in a subject, the method comprising administering a pharmaceutically effective amount of an anti-F protein epitope binder, e.g., antibody, or fragment thereof. In certain embodiments, a pharmaceutically effective amount reduces virus host cell fusion by at least 10%, or by at least 15%, or by at least 20%, or by at least 30%, or by at least 40%, or by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or by at least 95%, or by at least 99%, or by at least 99.5%.

The present invention further provides anti-F peptide antibodies or fragments thereof. Anti-F peptide antibodies of the invention include, but are not limited to, monoclonal antibodies, multispecific antibodies, human antibodies, humanized antibodies, chimeric antibodies, single-chain Fvs (scFv), single chain antibodies, Fab fragments, F (ab') fragments, disulfide-linked Fvs (sdFv), and anti-idiotypic (anti-Id) antibodies (including, e.g., anti-Id antibodies to antibodies of the invention), and epitope-binding fragments of any of the above. In particular, antibodies of the present invention include immunoglobulin molecules and immunologically active portions of immunoglobulin molecules, i.e., molecules that contain an antigen binding site that immunospecifically binds to a RSV antigen. The immunoglobulin molecules of the invention can be of any type (e.g., IgG, IgE, IgM, IgD, IgA and IgY), class (e.g., IgG.sub.1, IgG.sub.2, IgG.sub.3, IgG.sub.4, IgA.sub.1 and IgA2) or subclass of immunoglobulin molecule.

The antibodies of the invention may be from any animal origin including birds and mammals (e.g., human, murine, donkey, sheep, rabbit, goat, guinea pig, camel, horse, or chicken). Preferably, the antibodies of the invention are human or humanized monoclonal antibodies. As used herein, "human" antibodies include antibodies having the amino acid sequence of a human immunoglobulin and include antibodies isolated from human immunoglobulin libraries or from mice that express antibodies from human genes.

Antibodies of the present invention can be prepared using a wide variety of techniques known in the art including the use of hybridoma, recombinant, and phage display technologies, or a combination thereof. For example, monoclonal antibodies can be produced using hybridoma techniques including those known in the art and taught, for example, in Antibodies: A Laboratory Manual, E. Harlow and D. Lane, ed., Cold Spring Harbor Laboratory Press (Cold Spring Harbor, N.Y., 1988); and Hammerling, et al., in: Monoclonal Antibodies and T-Cell Hybridomas 563-681 (Elsevier, N.Y., 1981) (said references incorporated by reference in their entireties). The term "monoclonal antibody" as used herein is not limited to antibodies produced through hybridoma technology. The term "monoclonal antibody" refers to an antibody that is derived from a single clone, including any eukaryotic, prokaryotic, or phage clone, and not the method by which it is produced.

Methods for producing and screening for specific antibodies using hybridoma technology are routine and well known in the art. Briefly, mice (or other mammals) can be immunized with an antigen of interest (e.g., an F protein epitope of the invention), and once an immune response is detected, e.g., antibodies specific for an F protein epitope of the invention are detected in the mouse serum, the mouse spleen is harvested and splenocytes isolated. The splenocytes are then fused by well known techniques to any suitable myeloma cells, for example cells from cell line SP20 available from the ATCC. Hybridomas are selected and cloned by limited dilution. Additionally, a RIMMS (repetitive immunization, multiple sites) technique can be used to immunize an animal (Kilpatrick et al., 1997, Hybridoma 16:381-9, incorporated herein by reference in its entirety). Hybridoma clones are then assayed by methods known in the art for cells that secrete antibodies capable of binding a polypeptide of the invention. Ascites fluid, which generally contains high levels of antibodies, can be generated by immunizing mice with positive hybridoma clones.

For some uses, including in vivo use of antibodies in humans and in vitro detection assays, it may be preferable to use humanized antibodies or chimeric antibodies. Completely human antibodies and humanized antibodies are particularly desirable for therapeutic treatment of human subjects. Human antibodies can be made by a variety of methods known in the art including phage display methods described above using antibody libraries derived from human immunoglobulin sequences. See also U.S. Pat. Nos. 4,444,887 and 4,716,111; and International publication Nos. WO 98/46645, WO 98/50433, WO 98/24893, WO98/16654, WO 96/34096, WO 96/33735, and WO 91/10741; each of which is incorporated herein by reference in its entirety.

A humanized antibody is an antibody or its variant or fragment thereof which is capable of binding to a predetermined antigen and which comprises a framework region having substantially the amino acid sequence of a human immunoglobulin and a CDR having substantially the amino acid sequence of a non-human immunoglobulin. A humanized antibody comprises substantially all of at least one, and typically two, variable domains (Fab, Fab', F(ab').sub.2, Fv) in which all or substantially all of the CDR regions correspond to those of a non human immunoglobulin (i.e., donor antibody) and all or substantially all of the framework regions are those of a human immunoglobulin consensus sequence. Preferably, a humanized antibody also comprises at least a portion of an immunoglobulin constant region (Fc), typically that of a human immunoglobulin. Ordinarily, the antibody will contain both the light chain as well as at least the variable domain of a heavy chain. The antibody also may include the CH1, hinge, CH2, CH3, and CH4 regions of the heavy chain. The humanized antibody can be selected from any class of immuno-globulins, including IgM, IgG, IgD, IgA and IgE, and any isotype, including IgG1, IgG2, IgG3 and IgG4. Usually the constant domain is a complement fixing constant domain where it is desired that the humanized antibody exhibit cytotoxic activity, and the class is typically IgG1. Where such cytotoxic activity is not desirable, the constant domain may be of the IgG2 class. The humanized antibody may comprise sequences from more than one class or isotype, and selecting particular constant domains to optimize desired effector functions is within the ordinary skill in the art. The framework and CDR regions of a humanized antibody need not correspond precisely to the parental sequences, e.g., the donor CDR or the consensus framework may be mutagenized by substitution, insertion or deletion of at least one residue so that the CDR or framework residue at that site does not correspond to either the consensus or the import antibody. Such mutations, however, will not be extensive. Usually, at least 75% of the humanized antibody residues will correspond to those of the parental framework and CDR sequences, more often 90%, and most preferably greater than 95%. A humanized antibody can be produced using variety of techniques known in the art, including but not limited to, CDR-grafting (see e.g., European Patent No. EP 239,400; International Publication No. WO 91/09967; and U.S. Pat. Nos. 5,225,539, 5,530,101, and 5,585,089, each of which is incorporated herein in its entirety by reference), veneering or resurfacing (see e.g., European Patent Nos. EP 592,106 and EP 519,596; Padlan, 1991, Molecular Immunology 28(4/5):489-498; Studnicka et al., 1994, Protein Engineering 7(6):805-814; and Roguska et al., 1994, PNAS 91:969-973, each of which is incorporated herein by its entirety by reference), chain shuffling (see e.g., U.S. Pat. No. 5,565,332, which is incorporated herein in its entirety by reference), and techniques disclosed in, e.g., U.S. Pat. No. 6,407,213, U.S. Pat. No. 5,766,886, International Publication No. WO 9317105, Tan et al., 2002, J. Immunol. 169:1119-25, Caldas et al., 2000, Protein Eng. 13:353-60, Morea et al., 2000, Methods 20:267-79, Baca et al., 1997, J. Biol. Chem. 272:10678-84, Roguska et al., 1996, Protein Eng. 9:895-904, Couto et al., 1995, Cancer Res. 55:5973s-5977s, Couto et al., 1995, Cancer Res. 55:1717-22, Sandhu JS, 1994, Gene 150:409-10, and Pedersen et al., 1994, J. Mol. Biol. 235:959-73, each of which is incorporated herein in its entirety by reference. Often, framework residues in the framework regions will be substituted with the corresponding residue from the CDR donor antibody to alter, preferably improve, antigen binding. These framework substitutions are identified by methods well known in the art, e.g by modeling of the interactions of the CDR and framework residues to identify framework residues important for antigen binding and sequence comparison to identify unusual framework residues at particular positions. (See, e.g., Queen et al., U.S. Pat. No. 5,585,089; and Riechmann et al., 1988, Nature 332:323, which are incorporated herein by reference in their entireties.)

Human antibodies can also be produced using transgenic mice which are incapable of expressing functional endogenous immunoglobulins, but which can express human immunoglobulin genes. For example, the human heavy and light chain immunoglobulin gene complexes may be introduced randomly or by homologous recombination into mouse embryonic stem cells. Alternatively, the human variable region, constant region, and diversity region may be introduced into mouse embryonic stem cells in addition to the human heavy and light chain genes. The mouse heavy and light chain immunoglobulin genes may be rendered non functional separately or simultaneously with the introduction of human immunoglobulin loci by homologous recombination. In particular, homozygous deletion of the JH region prevents endogenous antibody production. The modified embryonic stem cells are expanded and microinjected into blastocysts to produce chimeric mice. The chimeric mice are then bred to produce homozygous offspring, which express human antibodies. The transgenic mice are immunized in the normal fashion with a selected antigen, e.g., all or a portion of a polypeptide of the invention. Monoclonal antibodies directed against the antigen can be obtained from the immunized, transgenic mice using conventional hybridoma technology. The human immunoglobulin transgenes harbored by the transgenic mice rearrange during B cell differentiation, and subsequently undergo class switching and somatic mutation. Thus, using such a technique, it is possible to produce therapeutically useful IgG, IgA, IgM and IgE antibodies. For an overview of this technology for producing human antibodies, see Lonberg and Huszar, 1995, Int. Rev. Immunol. 13:65-93. For a detailed discussion of this technology for producing human antibodies and human monoclonal antibodies and protocols for producing such antibodies, see, e.g., International publication Nos. WO 98/24893, WO 96/34096, and WO 96/33735; and U.S. Pat. Nos. 5,413,923, 5,625,126, 5,633,425, 5,569,825, 5,661,016, 5,545,806, 5,814,318, and 5,939,598, which are incorporated by reference herein in their entirety. In addition, companies such as Abgenix, Inc. (Freemont, Calif.) and Genpharm (San Jose, Calif.) can be engaged to provide human antibodies directed against a selected antigen using technology similar to that described above.

Human antibodies can also be derived from phage display of human antibody fragments. In phage display methods, functional antibody domains are displayed on the surface of phage particles, which carry the polynucleotide sequences encoding them. In particular, DNA sequences encoding V.sub.H and V.sub.L domains are amplified from animal cDNA libraries (e.g., human or murine cDNA libraries of lymphoid tissues). The DNA encoding the V.sub.H and V.sub.L domains are recombined together with an scFv linker by PCR and cloned into a phagemid vector (e.g., p CANTAB 6 or pComb 3 HSS). The vector is electroporated in E. coli and the E. coli is infected with helper phage. Phage used in these methods are typically filamentous phage including fd and M13 and the V.sub.H and V.sub.L domains are usually recombinantly fused to either the phage gene III or gene VIII. Phage expressing an antigen binding domain that binds to the antigen epitope of interest can be selected or identified with antigen, e.g., using labeled antigen or antigen bound or captured to a solid surface or bead. Examples of phage display methods that can be used to make the antibodies of the present invention include those disclosed in Brinkman et al., 1995, J. Immunol. Methods 182:41-50; Ames et al., 1995, J. Immunol. Methods 184:177; Kettleborough et al., 1994, Eur. J. Immunol. 24:952-958; Persic et al., 1997, Gene 187:9; Burton et al., 1994, Advances in Immunology 57:191-280; International Application No. PCT/GB91/01134; International Publication Nos. WO 90/02809, WO 91/10737, WO 92/01047, WO 92/18619, WO 93/1 1236, WO 95/15982, WO 95/20401, and WO97/13844; and U.S. Pat. Nos. 5,698,426, 5,223,409, 5,403,484, 5,580,717, 5,427,908, 5,750,753, 5,821,047, 5,571,698, 5,427,908, 5,516,637, 5,780,225, 5,658,727, 5,733,743 and 5,969,108; each of which is incorporated herein by reference in its entirety.

In a preferred embodiment, after phage selection, the antibody coding regions from the phage are isolated and used to generate whole antibodies, including human antibodies as described in the above references. In another preferred embodiment the reconstituted antibody of the invention is expressed in any desired host, including bacteria, insect cells, plant cells, yeast, and in particular, mammalian cells (e.g., as described below). Techniques to recombinantly produce Fab, Fab' and F(ab').sub.2 fragments can also be employed using methods known in the art such as those disclosed in International Publication No. WO 92/22324; Mullinax et al., 1992, BioTechniques 12:864; Sawai et al., 1995, AJRI 34:26; and Better et al., 1988, Science 240:1041 (said references incorporated by reference in their entireties).

A chimeric antibody is a molecule in which different portions of the antibody are derived from different immunoglobulin molecules. Methods for producing chimeric antibodies are known in the art. See e.g., Morrison, 1985, Science 229:1202; Oi et al., 1986, BioTechniques 4:214; Gillies et al., 1989, J. Immunol. Methods 125:191-202; and U.S. Pat. Nos. 5,807,715, 4,816,567, 4,816,397, and 6,311,415, which are incorporated herein by reference in their entirety.

The antibodies of the present invention may be monospecific, bispecific, trispecific or of greater multispecificity. Multispecific antibodies may be specific the F peptide as well as for a heterologous epitope, such as a heterologous polypeptide or solid support material. See, e.g., PCT publications WO 93/17715, WO 92/08802, WO 91/00360, and WO 92/05793; Tutt, et al., J. Immunol. 147:60-69(1991); U.S. Pat. Nos. 4,474,893, 4,714,681, 4,925,648, 5,573,920, and 5,601,819; and Kostelny et al., J. Immunol. 148:1547-1553 (1992) which are incorporated herein by reference in their entirety.

Anti-F peptide antibodies of the present invention or fragments thereof may be characterized in a variety of ways. In particular, antibodies of the invention or fragments thereof may be assayed for the ability to specifically bind to the F peptide. Such an assay may be performed in solution (e.g., Houghten, 1992, Bio/Techniques 13:412-421), on beads (Lam, 1991, Nature 354:82-84), on chips (Fodor, 1993, Nature 364:555-556), on bacteria (U.S. Pat. No. 5,223,409), on spores (U.S. Pat. Nos. 5,571,698; 5,403,484; and 5,223,409), on plasmids (Cull et al., 1992, Proc. Natl. Acad. Sci. USA 89:1865-1869) or on phage (Scott and Smith, 1990, Science 249:386-390; Devlin, 1990, Science 249:404-406; Cwirla et al., 1990, Proc. Natl. Acad. Sci. USA 87:6378-6382; and Felici, 1991, J. Mol. Biol. 222:301-310) (each of these references is incorporated herein in its entirety by reference). Antibodies or fragments thereof that have been identified to specifically bind to the F peptide or a fragment thereof can then be assayed for their specificity and affinity for a RSV antigen.

The anti-F peptide antibodies of the invention or fragments thereof may be assayed for specific binding to F peptides and cross-reactivity with other antigens by any method known in the art. Immunoassays which can be used to analyze immunospecific binding and cross-reactivity include, but are not limited to, competitive and non-competitive assay systems using techniques such as western blots, radioimmunoassays, ELISA (enzyme linked immunosorbent assay), "sandwich" immunoassays, immunoprecipitation assays, precipitin reactions, gel diffusion precipitin reactions, immunodiffusion assays, agglutination assays, complement-fixation assays, immunoradiometric assays, fluorescent immunoassays, protein A immunoassays, to name but a few. Such assays are routine and well known in the art (see, e.g., Ausubel et al, eds, 1994, Current Protocols in Molecular Biology, Vol. 1, John Wiley & Sons, Inc., New York, which is incorporated by reference herein in its entirety.

The invention provides polynucleotides comprising a nucleotide sequence encoding an anti-F peptide antibodyof the invention or a fragment thereof. The invention also encompasses polynucleotides that hybridize under high stringency, intermediate or lower stringency hybridization conditions, e.g., as defined supra, to polynucleotides that encode an antibody of the invention.

The present invention provides for anti-F peptide antibodies or fragments thereof that exhibit a high potency in an assay described herein. High potency and high affinity antibodies or fragments thereof can be produced by methods disclosed in copending U.S. patent application Ser. No. 09/796,848 and U.S. Pat. No. 6,656,467 (each of which are incorporated herein by reference) and methods described herein. For example, high potency antibodies can be produced by genetically engineering appropriate antibody gene sequences and expressing the antibody sequences in a suitable host. The antibodies produced can be screened to identify antibodies with, e.g., high k.sub.on values in a BIAcore assay.

The present invention also provides anti-F peptide antibodies or fragments thereof which immunospecifically bind to the F peptide and have an association rate constant or k.sub.on rate (antibody (Ab)+antigen (Ag) Ab-Ag) of at least 10.sup.5 M.sup.-1 s.sup.-1, or at least 5.times.10.sup.5 M.sup.-1 s.sup.-1, at least 10.sup.6M.sup.-1 s.sup.-1, or at least 5.times.10.sup.6M.sup.-1 s.sup.-1, or at least 10.sup.7M.sup.-1 s.sup.-1, or at least 5.times.10.sup.7 M.sup.-1 s.sup.-1, or at least 10.sup.8 M.sup.-1 s.sup.-1 as assessed using an described herein or known to one of skill in the art (e.g., a BIAcore assay).

The present invention provides anti-F peptide antibodies or fragments thereof that have a k.sub.off rate (antibody (Ab)+antigen (Ag) Ab-Ag) of less than 10.sup.-1 s.sup.-1, or of less than 5.times.10.sup.-1 s.sup.-1, or of less than 10.sup.-2 s.sup.-1, or of less than 5.times.10.sup.-2 s.sup.-1, or of less than 10.sup.-3 s.sup.-1, or of less than 5.times.10.sup.-3 s.sup.-1, or of less than 10.sup.-4 s.sup.-1, or of less than 5.times.10.sup.-4 s.sup.-1, or of less than 10.sup.-5 s.sup.-1, or of less than 5.times.10.sup.-5 s.sup.-1, or of less than 10.sup.-6 s.sup.-1, or of less than 5.times.10.sup.-6 s.sup.-1, or of less than 10.sup.-7 s.sup.-1, or of less than 5.times.10.sup.-7 s.sup.-1, or of less than 10.sup.-8 s.sup.-1, or of less than 5.times.10.sup.-8 s.sup.-1, or of less than 10.sup.-9 s.sup.-1, or of less than 5.times.10.sup.-9 s.sup.-1, or of less than 10.sup.-10 s.sup.-1 as assessed using an described herein or known to one of skill in the art (e.g., a BIAcore assay).

The present invention also provides anti-F peptide antibodies or fragments thereof that have an affinity constant or K.sub.a (k.sub.on/k.sub.off) of at least 10.sup.2 M.sup.-1, or at least 5.times.10.sup.2 M.sup.-1, or at least 10.sup.3 M.sup.-1, or at least 5.times.10.sup.3 M.sup.-1, or at least 10.sup.4 M.sup.-1, or at least 5.times.10.sup.4 M.sup.-1, or at least 10.sup.5 M.sup.-1, or at least 5.times.10.sup.5 M.sup.-1, or at least 10.sup.6 M.sup.-1, or at least 5.times.10.sup.6 M.sup.-1, or at least 10.sup.7 M.sup.-1, or at least 5.times.10.sup.7 M.sup.-1, or at least 10.sup.8 M.sup.-1, or at least 5.times.10.sup.8 M.sup.-1, or at least 10.sup.9 M.sup.-1, or at least 5.times.10.sup.9 M.sup.-1, or at least 10.sup.10 M.sup.-1, or at least 5.times.10.sup.10 M.sup.-1, or at least 10.sup.11 M.sup.-1, or at least 5.times.10.sup.11 M.sup.-1, or at least 10.sup.12 M.sup.-1, or at least 5.times.10.sup.12 M.sup.-1, or at least 101.sup.3 M.sup.-1, or at least 5.times.10.sup.13 M.sup.-1, or at least 10.sup.14 M.sup.-1, or at least 5.times.10.sup.14 M.sup.-1, or at least 10.sup.15 M.sup.-1, or at least 5.times.10.sup.15 M.sup.-1 as assessed using an described herein or known to one of skill in the art (e.g., a BIAcore assay).

The present invention provides anti-F peptide antibodies or fragments thereof that have a median effective concentration (EC.sub.50) of less than 0.01 nM, or of less than 0.025 nM, or of less than 0.05 nM, or of less than 0.1 or of nM, less than 0.25 or of nM, less than 0.5 or of nM, less than 0.75 nM, or of less than 1 nM, or of less than 1.25 nM, or of less than 1.5 nM, or of less than 1.75 nM, or of less than 2 nM, in an in vitro microneutralization assay. In particular, the present invention provides compositions for use in the prevention, treatment or amelioration of one or more symptoms associated with a RSV infection, said compositions comprising one or more antibodies (e.g., anti-F peptide antibodies) or fragments thereof which immunospecifically bind to one or more RSV antigens and have an EC.sub.50 of less than 0.01 nM, or of less than 0.025 nM, or of less than 0.05 nM, or of less than 0.1 nM, or of less than 0.25 nM, or of less than 0.5 nM, or of less than 0.75 nM, or of less than 1 nM, or of less than 1.25 nM, or of less than 1.5 nM, or of less than 1.75 nM, or of less than 2 nM, in an in vitro microneutralization assay.

The anti-F peptide antibodies of the invention include derivatives that are modified, i.e., by the covalent attachment of any type of molecule to the antibody such that covalent attachment. For example, but not by way of limitation, the antibody derivatives include antibodies that have been modified, e.g., by glycosylation, acetylation, pegylation, phosphorylation, amidation, derivatization by known protecting/blocking groups, proteolytic cleavage, linkage to a cellular ligand or other protein, etc. Any of numerous chemical modifications may be carried out by known techniques, including, but not limited to specific chemical cleavage, acetylation, formylation, metabolic synthesis of tunicamycin, etc. Additionally, the derivative may contain one or more non-classical amino acids.

The present invention also provides for F peptide binders, e.g., antibodies, or fragments thereof that have half-lives in a mammal, preferably a human, of greater than 15 days, preferably greater than 20 days, greater than 25 days, greater than 30 days, greater than 35 days, greater than 40 days, greater than 45 days, greater than 2 months, greater than 3 months, greater than 4 months, or greater than 5 months. The increased half-lives of the antibodies of the present invention or fragments thereof in a mammal, preferably a human, results in a higher serum titer of said antibodies or antibody fragments in the mammal, and thus, reduces the frequency of the administration of said antibodies or antibody fragments and/or reduces the concentration of said antibodies or antibody fragments to be administered. Binders having increased in vivo half-lives can be generated by techniques known to those of skill in the art. For example, antibodies or fragments thereof with increased in vivo half-lives can be generated by modifying (e.g., substituting, deleting or adding) amino acid residues identified as involved in the interaction between the Fc domain and the FcRn receptor (see, e.g., PCT Publication No. WO 97/34631, which is incorporated herein by reference in its entirety). Such binders can be tested for binding activity to RSV antigens as well as for in vivo efficacy using methods known to those skilled in the art, for example, by immunoassays described herein.

Further, antibodies or fragments thereof with increased in vivo half-lives can be generated by attaching to said antibodies or antibody fragments polymer molecules such as high molecular weight polyethyleneglycol (PEG). PEG can be attached to said antibodies or antibody fragments with or without a multifunctional linker either through site-specific conjugation of the PEG to the N- or C-terminus of said antibodies or antibody fragments or via epsilon-amino groups present on lysine residues. Linear or branched polymer derivatization that results in minimal loss of biological activity will be used. The degree of conjugation will be closely monitored by SDS-PAGE and mass spectrometry to ensure proper conjugation of PEG molecules to the antibodies. Unreacted PEG can be separated from antibody-PEG conjugates by, e.g., size exclusion or ion-exchange chromatography. PEG-derivatizated antibodies or fragments thereof can be tested for binding activity to RSV antigens as well as for in vivo efficacy using methods known to those skilled in the art, for example, by immunoassays described herein.

The present invention also provides for fusion proteins comprising an antibody or fragment thereof that specifically binds the F peptide and a heterologous polypeptide. Preferably, the heterologous polypeptide that the antibody or antibody fragment is fused to be useful for targeting the antibody to respiratory epithelial cells.

The present invention also provides for panels of anti-F peptide antibodies or fragments thereof. In specific embodiments, the invention provides for panels of antibodies or fragments thereof having different affinities for an RSV antigen, different specificities for an F peptide, or different dissociation rates. The invention provides panels of at least 10, or preferably at least 25, or at least 50, or at least 75, or at least 100, or at least 125, or at least 150, or at least 175, or at least 200, or at least 250, or at least 300, or at least 350, or at least 400, or at least 450, or at least 500, or at least 550, or at least 600, or at least 650, or at least 700, or at least 750, or at least 800, or at least 850, or at least 900, or at least 950, or at least 1000 antibodies or fragments thereof. Panels of antibodies can be used, for example, in 96 well plates for assays such as ELISAs.

Anti-F protein epitopes antibodies of the present invention or fragments thereof may be used, for example, to purify, detect, and target RSV antigens, in both in vitro and in vivo diagnostic and therapeutic methods. For example, the antibodies or fragments have use in immunoassays for qualitatively and quantitatively measuring levels of the RSV in biological samples such as sputum. See, e.g., Harlow et al., Antibodies: A Laboratory Manual, (Cold Spring Harbor Laboratory Press, 2nd ed. 1988) (incorporated by reference herein in its entirety).

The present invention encompasses antibodies or fragments thereof recombinantly fused or chemically conjugated (including both covalently and non-covalently conjugations) to a heterologous polypeptide (or portion thereof, preferably at least 10, or at least 20, or at least 30, or at least 40, or at least 50, or at least 60, or at least 70, or at least 80, or at least 90, or at least 100 amino acids of the polypeptide) to generate fusion proteins. The fusion does not necessarily need to be direct, but may occur through linker sequences. For example, antibodies may be used to target heterologous polypeptides to particular cell types (e.g., respiratory epithelial cells), either in vitro or in vivo, by fusing or conjugating the antibodies to antibodies specific for particular cell surface receptors. Antibodies fused or conjugated to heterologous polypeptides may also be used in vitro immunoassays and purification methods using methods known in the art. See e.g., PCT publication WO 93/21232; EP 439,095; Naramura et al., 1994, Immunol. Lett. 39:91-99; U.S. Pat. No. 5,474,981; Gillies et al., 1992, Proc. Natl. Acad. Sci. USA 89:1428-1432 and Fell et al., 1991, J. Immunol. 146:2446-2452, which are incorporated by reference in their entireties.

The present invention further includes compositions comprising heterologous polypeptides fused or conjugated to anti-F protein epitopes antibody fragments. For example, the heterologous polypeptides may be fused or conjugated to a Fab fragment, Fd fragment, Fv fragment, F(ab).sub.2 fragment, or portion thereof. Methods for fusing or conjugating polypeptides to antibody portions are known in the art. See, e.g., U.S. Pat. Nos. 5,336,603, 5,622,929, 5,359,046, 5,349,053, 5,447,851, and 5,112,946; EP 307,434; EP 367,166; PCT publication Nos. WO 96/04388 and WO 91/06570; Ashkenazi et al., 1991, Proc. Natl. Acad. Sci. USA 88: 10535-10539; Zheng et al., 1995, J. Immunol. 154:5590-5600; and Vil et al., 1992, Proc. Natl. Acad. Sci. USA 89:11337-11341 (said references incorporated by reference in their entireties).

Additional fusion proteins of the invention may be generated through the techniques of gene-shuffling, motif-shuffling, exon-shuffling, and/or codon-shuffling (collectively referred to as "DNA shuffling"). DNA shuffling may be employed to alter the activities of antibodies of the invention or fragments thereof (e.g., antibodies or fragments thereof with higher affinities and lower dissociation rates). See, generally, U.S. Pat. Nos. 5,605,793; 5,811,238; 5,830,721; 5,834,252; and 5,837,458, and Patten et al., 1997, Curr. Opinion Biotechnol. 8:724-33; Harayama, 1998, Trends Biotechnol. 16(2):76-82; Hansson, et al., 1999, J. Mol. Biol. 287:265-76 and Lorenzo and Blasco, 1998, Biotechniques 24(2):308-13 (each of these patents and publications are hereby incorporated by reference in its entirety). In one embodiment, antibodies or fragments thereof, or the encoded antibodies or fragments thereof, may be altered by being subjected to random mutagenesis by error-prone PCR, random nucleotide insertion or other methods prior to recombination. In another embodiment, one or more portions of a polynucleotide encoding an antibody or antibody fragment, which portions immunospecifically bind to a RSV antigen may be recombined with one or more components, motifs, sections, parts, domains, fragments, etc. of one or more heterologous molecules.

Moreover, the anti-F peptide antibodies of the present invention or fragments thereof can be fused to marker sequences, such as a peptide to facilitate purification. In preferred embodiments, the marker amino acid sequence is a hexa-histidine peptide, such as the tag provided in a pQE vector (QIAGEN, Inc., 9259 Eton Avenue, Chatsworth, Calif., 91311), among others, many of which are commercially available. As described in Gentz et al., 1989, Proc. Natl. Acad. Sci. USA 86:821-824, for instance, hexa-histidine provides for convenient purification of the fusion protein. Other peptide tags useful for purification include, but are not limited to, the hemagglutinin "HA" tag, which corresponds to an epitope derived from the influenza hemagglutinin protein (Wilson et al., 1984, Cell 37:767) and the "flag" tag.

The present invention further encompasses anti-F peptide binders e.g., antibodies, or fragments thereof conjugated to a diagnostic or therapeutic agent. The anti-F peptide antibodies can be used diagnostically to, for example, monitor the development or progression of a RSV infection as part of a clinical testing procedure to, e.g., determine the efficacy of a given treatment regimen. Detection can be facilitated by coupling the antibody or fragment thereof to a detectable substance. Examples of detectable substances include various enzymes, prosthetic groups, fluorescent materials, luminescent materials, bioluminescent materials, radioactive materials, positron emitting metals, and nonradioactive paramagnetic metal ions. The detectable substance may be coupled or conjugated either directly to the antibody (or fragment thereof) or indirectly, through an intermediate (such as, for example, a linker known in the art) using techniques known in the art. See, for example, U.S. Pat. No. 4,741,900 (incorporated herein by reference) for metal ions that can be conjugated to antibodies for use as diagnostics according to the present invention. Examples of suitable enzymes include horseradish peroxidase, alkaline phosphatase, beta-galactosidase, or acetylcholinesterase; examples of suitable prosthetic group complexes include streptavidin/biotin and avidin/biotin; examples of suitable fluorescent materials include umbelliferone, fluorescein, fluorescein isothiocyanate, rhodamine, dichlorotriazinylamine fluorescein, dansyl chloride or phycoerythrin; an example of a luminescent material includes luminol; examples of bioluminescent materials include luciferase, luciferin, and aequorin; and examples of suitable radioactive material include .sup.125I, .sup.131I, .sup.111In or .sup.99Tc.

A F protein epitope binder or fragment thereof may be conjugated to a therapeutic moiety such as a cytotoxin, e.g., a cytostatic or cytocidal agent, a therapeutic agent or a radioactive metal ion, e.g., alpha-emitters. A cytotoxin or cytotoxic agent includes any agent that is detrimental to cells. Examples include paclitaxol, cytochalasin B, gramicidin D, ethidium bromide, emetine, mitomycin, etoposide, tenoposide, vincristine, vinblastine, colchicin, doxorubicin, daunorubicin, dihydroxy anthracin dione, mitoxantrone, mithramycin, actinomycin D, 1-dehydrotestosterone, glucocorticoids, procaine, tetracaine, lidocaine, propranolol, and puromycin and analogs or homologs thereof. Therapeutic agents include, but are not limited to, antimetabolites (e.g., methotrexate, 6-mercaptopurine, 6-thioguanine, cytarabine, 5-fluorouracil decarbazine), alkylating agents (e.g., mechlorethamine, thioepa chlorambucil, melphalan, carmustine (BSNU) and lomustine (CCNU), cyclothosphamide, busulfan, dibromomannitol, streptozotocin, mitomycin C, and cisdichlorodiamine platinum (II) (DDP) cisplatin), anthracyclines (e.g., daunorubicin (formerly daunomycin) and doxorubicin), antibiotics (e.g., dactinomycin (formerly actinomycin), bleomycin, mithramycin, and anthramycin (AMC)), and anti-mitotic agents (e.g., vincristine and vinblastine).

Further, F protein epitope binder or fragment thereof may be conjugated to a therapeutic agent or drug moiety that modifies a given biological response. Therapeutic agents or drug moieties are not to be construed as limited to classical chemical therapeutic agents. For example, the drug moiety may be a protein or polypeptide possessing a desired biological activity. Such proteins may include, for example, a toxin such as abrin, ricin A, pseudomonas exotoxin, or diphtheria toxin; a protein such as tumor necrosis factor, .alpha.-interferon, .beta.-interferon, nerve growth factor, platelet derived growth factor, tissue plasminogen activator, an apoptotic agent, e.g., TNF-.alpha., TNF-.beta., AIM I (see, International Publication No. WO 97/33899), AIM II (see, International Publication No. WO 97/34911), Fas Ligand (Takahashi et al., 1994, J. Immunol., 6:1567-1574), and VEGI (see, International Publication No. WO 99/23105) 13 (each of these patents and publications are hereby incorporated by reference in its entirety), a thrombotic agent or an anti-angiogenic agent, e.g., angiostatin or endostatin; or, a biological response modifier such as, for example, a lymphokine (e.g., interleukin-1 ("IL-1"), interleukin-2 ("IL-2"), interleukin-6 ("IL-6"), granulocyte macrophage colony stimulating factor ("GM-CSF"), and granulocyte colony stimulating factor ("G-CSF")), or a growth factor (e.g., growth hormone ("GH")).

Techniques for conjugating such therapeutic moieties to antibodies are well known, see, e.g., Amon et al., "Monoclonal Antibodies For Immunotargeting Of Drugs In Cancer Therapy", in Monoclonal Antibodies And Cancer Therapy, Reisfeld et al. (eds.), pp. 243-56 (Alan R. Liss, Inc. 1985); Hellstrom et al., "Antibodies For Drug Delivery", in Controlled Drug Delivery (2nd Ed.), Robinson et al. (eds.), pp. 623-53 (Marcel Dekker, Inc. 1987); Thorpe, "Antibody Carriers Of Cytotoxic Agents In Cancer Therapy: A Review", in Monoclonal Antibodies '84: Biological And Clinical Applications, Pinchera et al. (eds.), pp. 475-506 (1985); "Analysis, Results, And Future Prospective Of The Therapeutic Use Of Radiolabeled Antibody In Cancer Therapy", in Monoclonal Antibodies For Cancer Detection And Therapy, Baldwin et al. (eds.), pp. 303-16 (Academic Press 1985), and Thorpe et al., 1982, Immunol. Rev. 62:119-5813 (each of these publications are hereby incorporated by reference in their entirety).

An antibody or fragment thereof, with or without a therapeutic moiety conjugated to it, administered alone or in combination with cytotoxic factor(s) and/or cytokine(s) can be used as a therapeutic. Alternatively, an antibody can be conjugated to a second antibody to form an antibody heteroconjugate as described by Segal in U.S. Pat. No. 4,676,980, which is incorporated herein by reference in its entirety. Antibodies may also be attached to solid supports, which are particularly useful for immunoassays or purification of the target antigen. Such solid supports include, but are not limited to, glass, cellulose, polyacrylamide, nylon, polystyrene, polyvinyl chloride or polypropylene.

In one embodiment, the invention is directed to aptamers of an F protein epitope of the invention (e.g., aptamers of F protein epitope of the invention). As is known in the art, aptamers are macromolecules composed of nucleic acid (e.g., RNA, DNA) that bind tightly to a specific molecular target (e.g., an F protein epitope of the invention and the natural F protein receptor). A particular aptamer may be described by a linear nucleotide sequence and an aptamer is typically about 15-60 nucleotides in length. The chain of nucleotides in an aptamer form intramolecular interactions that fold the molecule into a complex three-dimensional shape, and this three-dimensional shape allows the aptamer to bind tightly to the surface of its target molecule. Given the extraordinary diversity of molecular shapes that exist within the universe of all possible nucleotide sequences, aptamers may be obtained for a wide array of molecular targets, including proteins and small molecules. In addition to high specificity, aptamers have very high affinities for their targets (e.g., affinities in the picomolar to low nanomolar range for proteins). Aptamers are chemically stable and can be boiled or frozen without loss of activity. Because they are synthetic molecules, they are amenable to a variety of modifications, which can optimize their function for particular applications. For in vivo applications, aptamers can be modified to dramatically reduce their sensitivity to degradation by enzymes in the blood. In addition, modification of aptamers can also be used to alter their biodistribution or plasma residence time.

Selection of aptamers that can bind an F protein epitope of the invention and/or a natural F protein receptor can be achieved through methods known in the art. For example, aptamers can be selected using the SELEX (Systematic Evolution of Ligands by Exponential Enrichment) method (Tuerk, C., and Gold, L., Science 249:505-510 (1990)). In the SELEX method, a large library of nucleic acid molecules (e.g., 10.sup.15 different molecules) is produced and/or screened with the target molecule (e.g., an F protein epitope of the invention and/or a natural F protein receptor). The target molecule is allowed to incubate with the library of nucleotide sequences for a period of time. Several methods can then be used to physically isolate the aptamer target molecules from the unbound molecules in the mixture and the unbound molecules can be discarded. The aptamers with the highest affinity for the target molecule can then be purified away from the target molecule and amplified enzymatically to produce a new library of molecules that is substantially enriched for aptamers that can bind the target molecule. The enriched library can then be used to initiate a new cycle of selection, partitioning, and amplification. After 5-15 cycles of this selection, partitioning and amplification process, the library is reduced to a small number of aptamers that bind tightly to the target molecule. Individual molecules in the mixture can then be isolated, their nucleotide sequences determined, and their properties with respect to binding affinity and specificity measured and compared. Isolated aptamers can then be further refined to eliminate any nucleotides that do not contribute to target binding and/or aptamer structure (i.e., aptamers truncated to their core binding domain). See Jayasena, S. D. Clin. Chem. 45:1628-1650 (1999) for review of aptamer technology; the entire teachings of which are incorporated herein by reference).

In particular embodiments, the aptamers of the invention have the binding specificity and/or functional activity described herein for the anti-F peptide antibodies of the invention. Thus, for example, in certain embodiments, the present invention is drawn to aptamers that have the same or similar binding specificity as described herein for the anti-F peptide antibodies of the invention (e.g., binding specificity for an F protein epitope of the invention). In particular embodiments, the aptamers of the invention can bind to an F protein epitope of the invention and inhibit one or more functions of an F protein epitope of the invention. As described herein, function of an F protein epitope of the invention include but are not limited to, promoting viral-cell fusion, promoting cell-cell fusion leading to syncytia formation, binding to its natural receptor.

In another embodiment, the aptamers of the invention are molecular mimics of an F protein epitope, referred to herein as "aptamer F protein epitope mimic". In a specific embodiment, an aptamer F protein epitope mimic will be recognized by an anti-F peptide antibodyas described herein. Without wishing to be bound by theory or mechanism, it anticipated that an aptamer F protein epitope mimic could bind to the natural receptor of the RSV F protein and block binding of the RSV associated F protein thus, preventing F protein mediated fusion of RSV with the cell. In a particular embodiment, the aptamer F protein epitope mimic of the invention can inhibit one or more functions of an F protein epitope of the invention (supra).

Prophylactic and Therapeutic Uses of F Peptide Binders, e.g., Antibodies

One or more anti-F peptide binders of the present invention or fragments thereof may be used locally or systemically in the body as a therapeutic. The anti-F peptide binders of this invention or fragments thereof may also be advantageously utilized in combination with other monoclonal or chimeric antibodies, or with lymphokines or hematopoietic growth factors (such as, e.g., IL-2, IL-3 and IL-7), which, for example, serve to increase the number or activity of effector cells which interact with the antibodies. The anti-F peptide binders of this invention or fragments thereof may also be advantageously utilized in combination with one or more drugs used to treat RSV infection such as, for example anti-viral agents. Binders of the invention or fragments may be used in combination with one or more of the following drugs: NIH-351 (Gemini Technologies), recombinant RSV vaccine (MedImmune Vaccines), RSVf-2 (Intracel), F-50042 (Pierre Fabre), T-786 (Trimeris), VP-36676 (ViroPharma), RFI-641 (American Home Products), VP-14637 (ViroPharma), PFP-1 and PFP-2 (American Home Products), RSV vaccine (Avant Immunotherapeutics), and F-50077 (Pierre Fabre).

The anti-F peptide antibodies of the invention may be administered alone or in combination with other types of treatments (e.g., hormonal therapy, immunotherapy, and anti-inflammatory agents). Generally, administration of products of a species origin or species reactivity (in the case of antibodies) that is the same species as that of the patient is preferred. Thus, in a preferred embodiment, human or humanized antibodies, fragments derivatives, analogs, or nucleic acids, are administered to a human patient for therapy or prophylaxis.

In one embodiment, therapeutic or pharmaceutical compositions comprising anti-F peptide binders of the invention or fragments thereof are administered to a mammal, preferably a human, to treat, prevent or ameliorate one or more symptoms associated with RSV infection. In another embodiment, therapeutic or pharmaceutical compositions comprising an anti-F peptide binders or fragments thereof are administered to a human with cystic fibrosis, bronchopulmonary dysplasia, congenital heart disease, congenital immunodeficiency or acquired immunodeficiency, or to a human who has had a bone marrow transplant to treat, prevent or ameliorate one or more symptoms associated with RSV infection. In another embodiment, therapeutic or pharmaceutical compositions comprising F peptide binders of the invention or fragments thereof are administered to a human infant, preferably a human infant born prematurely or a human infant at risk of hospitalization for RSV infection to treat, prevent or ameliorate one or more symptoms associated with RSV infection. In yet another embodiment, therapeutic or pharmaceutical compositions comprising F peptide binders of the invention or fragments thereof are administered to the elderly or people in group homes (e.g., nursing homes or rehabilitation centers).

Otitis media is an infection or inflammation of the middle ear. This inflammation often begins when infections that cause sore throats, colds, or other respiratory or breathing problems spread to the middle ear. These can be viral or bacterial infections. RSV is the principal virus that has been correlated with otitis media. Seventy-five percent of children experience at least one episode of otitis media by their third birthday. Almost half of these children will have three or more ear infections during their first 3 years. It is estimated that medical costs and lost wages because of otitis media amount to $5 billion a year in the United States (Gates GA, 1996, Cost-effectiveness considerations in otitis media treatment; Otolaryngol Head Neck Sur. 114 (4): 525-530). Although otitis media is primarily a disease of infants and young children, it can also affect adults.

Otitis media not only causes severe pain but may result in serious complications if it is not treated. An untreated infection can travel from the middle ear to the nearby parts of the head, including the brain. Although the hearing loss caused by otitis media is usually temporary, untreated otitis media may lead to permanent hearing impairment. Persistent fluid in the middle ear and chronic otitis media can reduce a child's hearing at a time that is critical for speech and language development. Children who have early hearing impairment from frequent ear infections are likely to have speech and language disabilities.

Although many physicians recommend the use of antibiotics for the treatment of ear infections, antibiotic resistance has become an important problem in effective treatment of the disease. Further, new therapies are needed to prevent or treat viral infections that are associated with otitis media, particularly RSV.

About 12 million people in the U.S. have asthma and it is the leading cause of hospitalization for children. The Merck Manual of Diagnosis and Therapy (17th ed., 1999). Asthma is an inflammatory disease of the lung that is characterized by airway hyperresponsiveness ("AHR"), bronchoconstriction (i.e., wheezing), eosinophilic inflammation, mucus hypersecretion, subepithelial fibrosis, and elevated IgE levels. Asthmatic attacks can be triggered by environmental triggers (e.g. acarids, insects, animals (e.g., cats, dogs, rabbits, mice, rats, hamsters, guinea pigs, mice, rats, and birds), fungi, air pollutants (e.g., tobacco smoke), irritant gases, fumes, vapors, aerosols, chemicals, or pollen), exercise, or cold air. The cause(s) of asthma is unknown. However, it has been speculated that family history of asthma (London et al., 2001, Epidemiology 12(5):577-83), early exposure to allergens, such as dust mites, tobacco smoke, and cockroaches (Melen et al., 2001, 56(7):646-52), and respiratory infections (Wenzel et al., 2002, Am J Med, 112(8):672-33 and Lin et al., 2001, J Microbiol Immuno Infect, 34(4):259-64), such as RSV, may increase the risk of developing asthma. A review of asthma, including risk factors, animal models, and inflammatory markers can be found in O'Byme and Postma (1999), Am. J. Crit. Care. Med. 159:S41-S66, which is incorporated herein by reference in its entirety.

Current therapies are mainly aimed at managing asthma and include the administration of .beta.-adrenergic drugs (e.g. epinephrine and isoproterenol), theophylline, anticholinergic drugs (e.g., atropine and ipratorpium bromide), corticosteroids, and leukotriene inhibitors. These therapies are associated with side effects such as drug interactions, dry mouth, blurred vision, growth suppression in children, and osteoporosis in menopausal women. Cromolyn and nedocromil are administered prophylatically to inhibit mediator release from inflammatory cells, reduce airway hyperresponsiveness, and block responses to allergens. However, there are no current therapies available that prevent the development of asthma in subjects at increased risk of developing asthma. Thus, new therapies with fewer side effects and better prophylactic and/or therapeutic efficacy are needed for asthma.

Reactive airway disease is a broader (and often times synonymous) characterization for asthma-like symptoms, and is generally characterized by chronic cough, sputum production, wheezing or dyspenea. Wheezing (also known as sibilant rhonchi) is generally characterized by a noise made by air flowing through narrowed breathing tubes, especially the smaller, tight airways located deep within the lung. It is a common symptom of RSV infection, and secondary RSV conditions such as asthma and brochiolitis. The clinical importance of wheezing is that it is an indicator of airway narrowing, and it may indicate difficulty breathing. Wheezing is most obvious when exhaling (breathing out), but may be present during either inspiration (breathing in) or exhalation. Wheezing most often comes from the small bronchial tubes (breathing tubes deep in the chest), but it may originate if larger airways are obstructed.
 

Claim 1 of 15 Claims

1. An RSV F peptide consisting of an amino acid sequence, wherein said amino acid sequence has the following structure -- see Original Patent.
 

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