Chimeric neurotoxins

1. A chimeric neurotoxin comprising a LH N domain from a first neurotoxin covalently linked to a H C domain from a second neurotoxin, wherein:

the first and second neurotoxins are different;

the C-terminal amino acid residue of the LH N domain corresponds to the first amino acid residue of the 3 10 helix separating the LH N and H C domains in the first neurotoxin; and

the N-terminal amino acid residue of the H C domain corresponds to the second amino acid residue of the 3 10 helix separating the LH N and H C domains in the second neurotoxin.

2. The chimeric neurotoxin of claim 1 , wherein the first and second neurotoxins are each individually selected from botulinum neurotoxin (BoNT) serotypes A, B, C, D, E, F, or G, or Tetanus neurotoxin (TeNT).

3. The chimeric neurotoxin of claim 1 , wherein the LH N domain corresponds to:

amino acid residues 1 to 872 of SEQ ID NO: 1, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 859 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 867 of SEQ ID NO: 3, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 863 of SEQ ID NO: 4, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 846 of SEQ ID NO: 5, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 865 of SEQ ID NO: 6, or a sequence having at least 70% sequence identity thereto;

amino acid residues 1 to 864 of SEQ ID NO: 7, or a sequence having at least 70% sequence identity thereto; or

amino acid residues 1 to 880 of SEQ ID NO: 8, or a sequence having at least 70% sequence identity thereto;

and wherein the H C domain corresponds to:

amino acid residues 873 to 1296 of SEQ ID NO: 1, or a sequence having at least 70% sequence identity thereto;

amino acid residues 860 to 1291 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto;

amino acid residues 868 to 1291 of SEQ ID NO: 3, or a sequence having at least 70% sequence identity thereto;

amino acid residues 864 to 1276 of SEQ ID NO: 4, or a sequence having at least 70% sequence identity thereto;

amino acid residues 847 to 1251 of SEQ ID NO: 5, or a sequence having at least 70% sequence identity thereto;

amino acid residues 866 to 1275 of SEQ ID NO: 6, or a sequence having at least 70% sequence identity thereto;

amino acid residues 865 to 1297 of SEQ ID NO: 7, or a sequence having at least 70% sequence identity thereto; or

amino acid residues 881 to 1315 of SEQ ID NO: 8, or a sequence having at least 70% sequence identity thereto.

4. The chimeric neurotoxin of claim 1 , wherein the first neurotoxin is a BoNT/A and wherein the second neurotoxin is a BoNT/B.

5. The chimeric neurotoxin of claim 4 , wherein the first neurotoxin is a BoNT/A1 and the second neurotoxin is a BoNT/B1.

6. The chimeric neurotoxin of claim 5 , wherein the LH N domain corresponds to amino acid residues 1 to 872 of SEQ ID NO: 1, or a sequence having at least 70% sequence identity thereto, and the H C domain corresponds to amino acid residues 860 to 1291 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto.

7. The chimeric neurotoxin of claim 4 , wherein the H C domain comprises at least one amino acid residue substitution, addition or deletion in the H CC subdomain that has the effect of increasing the binding affinity of the H C domain for the human Syt II receptor as compared to the natural sequence.

8. The chimeric neurotoxin of claim 7 , wherein the H C domain corresponds to amino acid residues 860 to 1291 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto, and comprises an amino acid substitution selected from the group consisting of: V1118M; Y1183M; E1191M; E1191I; E1191Q; E1191T; S1199Y; S1199F; S1199L; S1201V; E1191C; E1191V, E1191L; E1191Y; S1199W; S1199E; S1199H; W1178Y; W1178Q; W1178A; W1178S; Y1183C; and Y1183P.

9. The chimeric neurotoxin of claim 7 , wherein the H C domain corresponds to amino acid residues 860 to 1291 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto, and comprises two amino acid substitutions selected from the group consisting of: E1191M and S1199L; E1191M and S1199Y; E1191M and S1199F; E1191Q and S1199L; E1191Q and S1199Y; E1191Q and S1199F; E1191M and S1199W; E1191M and W1178Q; E1191C and S1199W; E1191C and S1199Y; E1191C and W1178Q; E1191Q and S1199W; E1191V and S1199W; E1191V and S1199Y; and E1191V and W1178Q.

10. The chimeric neurotoxin of claim 9 , wherein the substitutions are E1191M and S1199Y.

11. The chimeric neurotoxin of claim 7 , wherein the H C domain corresponds to amino acid residues 860 to 1291 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto, and comprises the following substitutions: E1191M; S1199W; and W1178Q.

12. The chimeric neurotoxin of claim 1 , wherein the first neurotoxin is a BoNT/B and the second neurotoxin is a BoNT/C.

13. The chimeric neurotoxin of claim 12 , wherein the first neurotoxin is a BoNT/B1 and the second neurotoxin is a BoNT/C1.

14. The chimeric neurotoxin of claim 13 , wherein the LH N domain corresponds to amino acid residues 1 to 859 of SEQ ID NO: 2, or a sequence having at least 70% sequence identity thereto, and the H C domain corresponds to amino acid residues 868 to 1291 of SEQ ID NO: 3, or a sequence having at least 70% sequence identity thereto.

15. A pharmaceutical composition comprising the chimeric neurotoxin of claim 1 , and a pharmaceutically acceptable carrier, an excipient, an adjuvant, a propellant, and/or a salt.

16. A kit comprising the pharmaceutical composition of claim 15 and instructions for therapeutic or cosmetic administration of the composition to a subject in need thereof.

17. A method for producing the chimeric neurotoxin of claim 1 , the method comprising the step of culturing a cell comprising a nucleotide sequence encoding the chimeric neurotoxin under conditions wherein the chimeric neurotoxin is produced.