The present invention relates to a polypeptide binding to a chymase (EC 3.4.21.39), wherein the polypeptide comprises or consists of an amino acid sequence selected from the group consisting of: (a) GVTLFVALYDY(X 1 )A(X 2 )(X 3 )(X 4 )(X 5 )(X 6 )LSFHKGEKFQIL(X 1 )(X 8 )(X 9 )(X 10 )(X 11 )(X 12 )G(X 13 )(X 14 )WEARS LTTGETGYIPSNYVAPVDSIQ (SEQ ID NO: 1), wherein (X 1 ) is R, N, Q, E, K, H, S, T, C, or D； (X 2 ) is E, T, D, Q, L, P, A, S, C, M, N, E, G, A, V or I； (X 3 ) is R, T, H, N, K, S, C, N or Q； (X 4 ) is S, W, T, C, N, Q, F or Y； (X 5 ) is T, H, L, F, C, S, M, N, Q, R, K, G, A, V, I, P, Y or W； (X 6 ) is D, Q, H, E, S, T, C, N, R or K； (X 7 ) is D, N, R, E, Q, S, T, C, K or D； (X 8 ) is M, W, G, F, A, S, T, C, S, N, Q, Y, V, L, I or P； (X 9 ) is T, H, S, D, C, N, Q, R, K, E or absent； (X 10 ) is V, T, Q, G, A, L, I, P, S, C, M, N or absent； (X 11 ) is P, A, D, G, K, V, L, I, E, R, M, H or absent； (X 12 ) is N, V, P, I, E, T, S, A, G, L, C, M, Q or D； (X 13 ) is D, E, T, P, G, A, V, L, I, S, C, M, N or Q, and (X 14 ) is W, Y, L, G, A, V, I, P, M, or F； (b) an amino acid sequence which is at least 85% identical to the amino acid sequence of (a), wherein the identity determination excludes amino acid positions (X 1 ) to (X 14 ).
