abstract |
An albumin variant or fragment thereof comprising said albumin variant or fragment thereof, comprising a substitution at a position corresponding to position 573 in SEQ ID NO: 2, wherein: (i) the variant or fragment has at least 98% sequence identity with SEQ ID NO: 2; (ii) the substitution is A, C, D, F, G, H, I, L, M, N, P, R, S, V, W or Y; and (iii) the variant or fragment has a stronger FcRn binding affinity and / or a longer plasma half-life than an original albumin comprising SEQ ID NO: 2 or fragment thereof, in which the binding affinity Stronger is defined as the variant of albumin or fragment that has a binding coefficient (KD) to FcRn of less than 0.9X the binding coefficient of SEQ ID NO: 2, or corresponding fragment of SEQ ID NO: 2, at FcRn. |