US 12,221,492 B2
Mutated immunoglobulin-binding polypeptides
Gustav Rodrigo, Uppsala (SE); Tomas Bjorkman, Uppsala (SE); and Mats Ander, Uppsala (SE)
Assigned to Cytiva BioProcess R&D AB, Uppsala (SE)
Filed by Cytiva BioProcess R&D AB, Uppsala (SE)
Filed on Jan. 15, 2021, as Appl. No. 17/149,830.
Application 17/149,830 is a continuation of application No. 15/525,688, granted, now 11,566,082, previously published as PCT/EP2015/076642, filed on Nov. 16, 2015.
Claims priority of application No. 1451376-6 (SE), filed on Nov. 17, 2014; application No. 1510261 (GB), filed on Jun. 12, 2015; and application No. 1510263 (GB), filed on Jun. 12, 2015.
Prior Publication US 2021/0147577 A1, May 20, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C07K 16/46 (2006.01); B01D 15/38 (2006.01); B01J 20/289 (2006.01); B01J 20/32 (2006.01); C07K 1/22 (2006.01); C07K 14/31 (2006.01); C07K 16/00 (2006.01); C07K 16/06 (2006.01)
CPC C07K 16/46 (2013.01) [B01D 15/3809 (2013.01); B01J 20/289 (2013.01); B01J 20/3219 (2013.01); B01J 20/3274 (2013.01); C07K 1/22 (2013.01); C07K 14/31 (2013.01); C07K 16/00 (2013.01); C07K 16/065 (2013.01)] 13 Claims
 
1. An Fc-binding polypeptide comprising a mutant of an Fc-binding domain of Staphylococcus Protein A (SpA) as defined by a consensus sequence KEX1QX2AFYEILX3LPNLTEEQRNAFIQX6LKDX7PSQSX9X10X11LAEAKX12X13ND AQAPK (SEQ ID NO:28), wherein X7 is E and X9 is R, and wherein individually of each other at least one of X1, X2, X3, X6, X10, X11, X12, and X13 is substituted as follows:
X1=A or else Q,
X2=K or else or N,
X3=K or else H,
X6=K or else S,
X10=A or else N,
X11=I or else L,
X12=R or else K,
X13=Y or else L,
and wherein the mutant binds the Fc domain of an antibody and has improved alkaline stability compared to the amino acid sequence of SEQ ID NO:7, wherein the alkaline stability is improved as measured by the remaining IgG-binding capacity after 24 or 25 h incubation in 0.5 M or 1.0 M aqueous NaOH at 22+/−2° C.