Conjugates comprising an GLP-1/Glucagon dual agonist, a linker and hyaluronic acid

A process for the preparation of a peptide-linker-conjugate or salt or solvate thereof of general formula L2*-L-Y, comprising the steps of:

• (a) assembling the amino acid sequence of the peptide moiety Y with protected reactive functional groups in the side chains using solid phase peptide synthesis (SPPS) on a resin, including D-Ser in position 2, wherein the side chain of lysine at position 14 is protected by a monomethoxytrityl (Mmt) group;
• (b) coupling histidine as Fmoc-His(Trt)-OH at position 1;
• (c) deprotection of 9-fluorenylmethyloxycarbonyl (Fmoc);
• (d) coupling of the linker reagent L of formula (Iaa):
• (e) deprotecting the Mmt protecting group at position 14;
• coupling Palm-Glu(γOSu)-OtBu or Stea-Glu(γOSu)-OtBu at position 14;
• and
• (g) cleaving the peptide from the resin and deprotection of all protected groups,
• wherein:
• L2* is a C1-20 alkyl chain, which is optionally interrupted by one or more groups independently selected from —O— and C(O)N(R3aa) and is optionally substituted with one or more groups independently selected from OH and C(O)N(R3aaR3aaa), and comprises a chemical functional group intended for conjugation to an L1 group of a functionalized hyaluronic acid, wherein L1 is a C1-20 alkyl chain comprising a terminal amino group, in which optionally one or more carbon atoms are replaced by a group selected from —O—, N(R5aa) and C(O)N(R5aa) and which is optionally substituted with one or more groups independently selected from OH and C(O)N(R5aaR5aaa), wherein R5aa and R5aaa are independently selected from the group consisting of H and C1-4 alkyl;
• X is C(R4R4a) or N(R4);
• each R1, R1a, R2a, R3aa, R3aaa, R4, and R4a is independently selected from the group consisting of H and C1-4 alkyl;
• PA is OH or an activating group;
• and
• Y is a peptide moiety of formula (Ib):
• (Ib)
• His-D-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-
• Lys-Gln-X14-Glu-Ser-Lys-Ala-Ala-Gln-Asp-Phe-
• Ile-Glu-Trp-Leu-Lys-Ala-Gly-Gly-Pro-Ser-Ser-
• Gly-Ala-Pro-Pro-Pro-Ser,
• wherein X14 is Lys, wherein the —NH2 side chain group is functionalized by (S)-4-carboxy-4-hexadecanoylamino-butyryl;
• or
• Y is a peptide moiety of formula (Ic):
• (Ic)
• His-D-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-
• Lys-Gln-X14-Asp-Glu-Gln-Leu-Ala-Lys-Asp-Phe-
• Ile-Glu-Trp-Leu-Lys-Ala-Gly-Gly-Pro-Ser-Ser-
• Gly-Ala-Pro-Pro-Pro-Ser,
• wherein X14 is Lys, wherein the —NH2 side chain group is functionalized by (S)-4-carboxy-4-octadecanoylamino-butyryl.