Respiratory syncytial virus surface glycoprotein peptides, conjugates, and uses thereof

A conjugate comprising (i) a structurally-stabilized peptide and (ii) cholesterol or thiocholesterol;

• wherein the cholesterol or thiocholesterol are linked, directly or via a linker, to the C-terminal amino acid of the structurally-stabilized peptide;
• wherein the structurally-stabilized peptide comprises an internally cross-linked amino acid sequence having the formula:
• or a pharmaceutically acceptable salt thereof;
• wherein each R1 and R2 is H or a C1 to C10 alkyl, alkenyl, alkynyl, arylalkyl, cycloalkylalkyl, heteroarylalkyl, or heterocyclylalkyl, any of which is substituted or unsubstituted;
• wherein x is 3 or 6;
• wherein each R3 is independently alkylene, alkenylene, or alkynylene, any of which is substituted or unsubstituted;
• wherein z is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10;
• wherein the internally cross-linked amino sequence comprises (i) 25 to 29 contiguous amino acids of the sequence of SEQ ID NO:100, or (ii) the sequence SDEFDASISQVNEKINQSLAFIRKSDELLHNV (SEQ ID NO:280), except for two to six amino acid substitutions relative to the sequence of SEQ ID NO:100 or 281 and wherein the internally cross-linked amino acid sequence does not include the sequence NAGKST (SEQ ID NO:258);
• wherein the conjugate binds to an RSV 5-helix bundle protein and/or wherein the conjugate inhibits infection of a cell by RSV and/or prevents infection of a cell by RSV;
• and
• wherein the conjugate is 25 to 45 amino acids in length, optionally wherein the conjugate is 30 amino acids in length.

A structurally-stabilized peptide, comprising:

• an internally cross-linked amino acid sequence comprising 25 to 29 contiguous amino acids of the sequence FDASISQVNEKINQSLAFIRKSDELLHNV (SEQ ID NO:100), except for two to six amino acid substitutions relative to the sequence of SEQ ID NO:100;
• wherein two of the two to six amino acid substitutions are with α, α-disubstituted non-natural amino acids with olefinic side chains cross-linked to each other, wherein the α, α-disubstituted non-natural amino acids with olefinic side chains cross-linked to each other are separated by three or six amino acids;
• wherein the structurally-stabilized peptide binds to an RSV 5-helix bundle protein and/or wherein the structurally-stabilized peptide inhibits infection of a cell by RSV and/or prevents infection of a cell by RSV;
• and
• wherein the structurally-stabilized peptide is 25 to 32 amino acids in length, optionally wherein the structurally-stabilized peptide is 32 amino acids in length, optionally, wherein the structurally-stabilized peptide comprises three N-terminal amino acids X1 X2X3 immediately upstream of the first F of SEQ ID NO:
• 100, wherein X1 is any amino acid, optionally S, and X2 and X3 are negatively charged amino acids.

A structurally-stabilized peptide, comprising:

• an internally cross-linked amino acid sequence having the formula:
• or a pharmaceutically acceptable salt thereof;
• wherein each R1 and R2 is H or a C1 to C10 alkyl, alkenyl, alkynyl, arylalkyl, cycloalkylalkyl, heteroarylalkyl, or heterocyclylalkyl, any of which is substituted or unsubstituted;
• wherein x is 3 or 6;
• wherein each R3 is independently alkylene, alkenylene, or alkynylene, any of which is substituted or unsubstituted;
• wherein z is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10;
• and
• wherein the internally cross-linked amino sequence comprises 25 to 29 contiguous amino acids of the sequence of SEQ ID NO:100, except for two to six amino acid substitutions relative to the sequence of SEQ ID NO:100;
• wherein the structurally-stabilized peptide binds to an RSV 5-helix bundle protein and/or wherein the structurally-stabilized peptide inhibits infection of a cell by RSV and/or prevents infection of a cell by RSV;
• and
• wherein the structurally-stabilized peptide is 25 to 30 amino acids in length, optionally wherein the structurally-stabilized peptide is 29 amino acids in length.

A method of making a structurally-stabilized peptide, the method comprising:

• I. (a) providing a peptide having an amino acid sequence comprising 25 to 29 contiguous amino acids of the sequence FDASISQVNEKINQSLAFIRKSDELLHNV (SEQ ID NO:100), except for two to six amino acid substitutions relative to the sequence of SEQ ID NO:100, ;
• wherein two of the two to six amino acid substitutions are with α, α-disubstituted non-natural amino acids with olefinic side chains, wherein the α, α-disubstituted non-natural amino acids with olefinic side chains are separated by three or six amino acids;
• and
• (b) cross-linking the peptide, thereby making the structurally-stabilized peptide, and optionally purifying the structurally-stabilized peptide;
• or
• II. (a′) providing a peptide comprising the sequence SDEFDASISQVNEKINQSLAFIRKSDELLHNV (SEQ ID NO:280), except for two to six amino acid substitutions relative to the sequence of SEQ ID NO:280;
• wherein two of the two to six amino acid substitutions are with α, α-disubstituted non-natural amino acids with olefinic side chains, wherein the α, α-disubstituted non-natural amino acids with olefinic side chains are separated by three or six amino acids;
• and
• (b′) cross-linking the peptide, thereby making the structurally-stabilized peptide, and optionally purifying the structurally-stabilized peptide.