Adjuvanting meningococcal factor h binding protein

Abstract

Factor H binding protein (fHBP) has been proposed for use in immunising against serogroup B meningococcus (‘MenB’). This antigen can be efficiently adsorbed to an aluminium hydroxyphosphate adjuvant by (i) ensuring that adsorption takes place at a pH which is equal to or below the adjuvant's point of zero charge (PZC), and/or (ii) selecting a fHBP and adjuvant with an isoelectric point/PZC within the range of 5.0 to 7, and/or (iii) selecting a fHBP with an isoelectric point above the adjuvant's PZC and using a buffer to bring the pH to within 1.2 pH units of the PZC. The adsorption is particularly useful for compositions which include multiple fHBP variants, and also in situations where an aluminium hydroxide adjuvant should be avoided. Buffered pharmaceutical compositions can include at least two different meningococcal fHBP antigens, both of which are at least 85% adsorbed to aluminium hydroxyphosphate adjuvant.

What is claimed: 
     
         1 . A buffered immunogenic composition comprising at least two different meningococcal fHBP antigens, both of which are at least 85% adsorbed to aluminium hydroxyphosphate adjuvant. 
     
     
         2 . The composition of  claim 1 , wherein (i) each of the two different fHBP antigens has an isoelectric point between 5.0 and 7.0, and (ii) the aluminium hydroxyphosphate adjuvant has a point of zero charge between 5.0 and 7.0. 
     
     
         3 . The composition of  claim 2 , wherein the pH of the buffered composition is in the range of 5.0 to 7.0. 
     
     
         4 . An immunogenic composition comprising two different meningococcal fHBP antigens, both of which are adsorbed to aluminium hydroxyphosphate adjuvant, wherein (i) both of the meningococcal fHBP antigens have an isoelectric point between 5.0 and 7.0, and (ii) the aluminium hydroxyphosphate adjuvant has a point of zero charge between 5.0 and 7.0. 
     
     
         5 . A buffered immunogenic composition comprising two different meningococcal fHBP antigens, both adsorbed to aluminium hydroxyphosphate adjuvant, wherein (i) each meningococcal fHBP antigen has an isoelectric point which is greater than the adjuvant's point of zero charge and (ii) the composition has a pH which is within 1.2 pH units of the adjuvant's point of zero charge. 
     
     
         6 . The composition of  claim 4 , including a buffer to maintain pH in the range of 5.0 to 7.0. 
     
     
         7 . The composition of  claim 4 , wherein both of the meningococcal fHBP antigens have an isoelectric point between 5.0 and 6.0. 
     
     
         8 . The composition of  claim 4 , wherein the aluminium hydroxyphosphate has an isoelectric point between 5.0 and 6.0. 
     
     
         9 . The composition of  claim 1 , wherein (i) both of the meningococcal fHBP antigens have an isoelectric point between 5.0 and 6.0 and (ii) the aluminium hydroxyphosphate has an isoelectric point between 5.0 and 6.0. 
     
     
         10 . The composition of  claim 9 , wherein the immunogenic composition includes a buffer to maintain pH in the range of 5.0 to 7.0. 
     
     
         11 . The composition of  claim 10 , wherein the immunogenic composition includes a buffer to maintain pH in the range of 5.0 to 6.0. 
     
     
         12 . The composition of  claim 5 , including a buffer which maintains the pH within 1.2 pH units of the adjuvant's point of zero charge. 
     
     
         13 . The composition of  claim 4 , wherein the composition has a pH which is within 0.5 pH unit of the adjuvant's point of zero charge. 
     
     
         14 . The composition of  claim 13 , including a buffer which maintains the pH within 0.5 pH unit of the adjuvant's point of zero charge. 
     
     
         15 . The composition of  claim 1 , wherein the two different fHBP antigens are: (i) a first and second polypeptide; (ii) a first and third polypeptide; or (iii) a second and third polypeptide, selected from: (a) a first polypeptide comprising an amino acid sequence (i) having at least 84% sequence identity to SEQ ID NO: 1 and/or (ii) consisting of a fragment of at least 20 contiguous amino acids from SEQ ID NO: 1; (b) a second polypeptide, comprising an amino acid sequence (i) having at least 84% sequence identity to SEQ ID NO: 2 and/or (ii) consisting of a fragment of at least 20 contiguous amino acids from SEQ ID NO: 2; (c) a third polypeptide, comprising an amino acid sequence (i) having at least 84% sequence identity to SEQ ID NO: 3 and/or (ii) consisting of a fragment of at least 20 contiguous amino acids from SEQ ID NO: 3. 
     
     
         16 . The composition of  claim 4 , wherein the composition does not include an aluminium hydroxide adjuvant. 
     
     
         17 . The composition of  claim 16 , comprising a conjugated bacterial capsular saccharide. 
     
     
         18 . The composition of  claim 1 , wherein the fHBP polypeptides are lipidated at a N-terminus cysteine, wherein the lipid comprises palmitoyl. 
     
     
         19 . The composition of  claim 1 , wherein the aluminium hydroxyphosphate has a PZC between 5.4 and 6.2. 
     
     
         20 . The composition of  claim 1 , wherein the aluminium hydroxyphosphate has a P/Al molar ratio between 0.85 and 1.0. 
     
     
         21 . The composition of  claim 1 , wherein the aluminium hydroxyphosphate is amorphous and particulate comprising plates with diameters 10-100 nm. 
     
     
         22 . The composition of  claim 1 , wherein the Al +++  concentration is <2 mg/ml.