HK1206587B

HK1206587B - Immunogenic composition

Info

Publication number: HK1206587B
Application number: HK15105322.1A
Authority: HK
Inventors: Ralph Leon Biemans; Dominique Boutriau; Carine Capiau; Philippe Denoel; Pierre Duvivier; Jan Poolman
Original assignee: Glaxosmithkline Biologicals S.A.
Priority date: 2005-06-27
Filing date: 2008-06-12
Publication date: 2020-04-29

Description

The present invention relates to immunogenic compositions comprising N. meningitidis bacterial capsular saccharides conjugated to a carrier protein. It additionally relates to vaccines and vaccine kits comprising such saccharide conjugates, processes for making the immunogenic compositions and vaccines and the vaccines and immunogenic compositions of the invention for use in the treatment or prevention of disease caused by N. meningitidis infection . Also disclosed are methods of immunising against infection using the saccharide conjugates and the use of the saccharide conjugates in the manufacture of a medicament.

Neisseria meningitidis is a Gram-negative human pathogen which causes bacterial meningitis. Based on the organism's capsular polysaccharide, twelve serogroups of N. meningitidis have been identified (A, B, C, H, I, K, L, 29E, W135, X, Y and Z). Serogroup A (MenA) is the most common cause of epidemic disease in sub-Saharan Africa. Serogroups B and C are responsible for the majority of cases in developing countries, with the remaining cases being caused by W135 and Y.

Immunogenic compositions comprising N. meningitidis saccharides conjugated to carrier proteins are known in the art; the carrier protein having the known effect of turning the T-independent polysaccharide antigen into a T-dependent antigen capable of triggering an immune memory response. For instance WO 02/58737 discloses a vaccine comprising purified capsular polysaccharides from N. meningitidis serogroups A, C, W135 and Y conjugated to a carrier protein. However, this application teaches that all polysaccharides should essentially be conjugated in the same way (through the same linker to the same protein carrier).

WO2004/103400 refers to multivalent meningococcal derivatized polysaccharide-protein conjugates and vaccine.

Also referred to is Rennels et al (2002) The Pediatric Infectious Disease Journal, 21(10): 978-9 which is concerned with dose escalation, safety and immunogenicity study of a tetravalent meningococcal polysaccharide diphtheria conjugate vaccine in toddlers.

There remains a need to develop improved conjugate vaccines against neisserial meningitis. The present invention concerns the provision of a meningococcal polysaccharide conjugate vaccine where conjugation of each polysaccharide is tailored (rather than being uniform) to achieve an efficacious combination vaccine. In particular it is advantageous to combine certain meningococcal saccharides conjugated to their protein carriers at a high saccharide:protein ratio with others at a low ratio.

Accordingly, in one aspect of the present invention there is provided an immunogenic composition comprising N. meningitidis serogroup A capsular saccharide (MenA), N. meningitidis serogroup C capsular saccharide (MenC), N. meningitidis serogroup Y capsular saccharide (MenY) and N. meningitidis serogroup W capsular saccharide (MenW) conjugated separately to the same type of carrier protein, wherein:

(a) MenA or MenA and MenC are conjugated to the carrier protein via a carboxyl group on the protein carrier and an ADH linker, wherein the or each capsular saccharide(s) conjugated via the ADH linker is/are conjugated to the linker with CDAP chemistry and the carrier protein is conjugated to the ADH linker with EDAC chemistry, wherein the saccharide:protein ratio (w/w) is between 1:2-1:5;
(b) the N. meningitidis saccharides from MenC, MenY and MenW distinct from (a), are conjugated to the carrier protein via an amino group on the protein carrier, wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99; and
(c) the carrier protein is TT.

In a MenW vaccine the ratio of Men W saccharide to carrier protein can be between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1:1-1:1.7, 1:1.2-1:1.6, or 1:1.4-1:1.5 (w/w). In a MenY vaccine the ratio of Men Y saccharide to carrier protein can be between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.9, 1:1-1:1.8, 1:1.1-1:1.6, or 1:1.3-1:1.4 (w/w). In a MenA vaccine the ratio of Men A saccharide to carrier protein can be between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w). In a Men C vaccine the ratio of Men C saccharide to carrier protein can be between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w), or between 1:2-1:5, 1:2.5-1:4.5, 1:2.7-1:4.3, 1:3-1:4, or 1:3.3-1:3.5 (w/w).

The ratio of saccharide to carrier protein (w/w) in a conjugate may be determined using the sterilized conjugate. The amount of protein is determined using a Lowry assay (for example Lowry et al (1951) J. Biol. Chem. 193, 265-275 or Peterson et al Analytical Biochemistry 100, 201-220 (1979)) and the amount of saccharide is determined using ICP-OES (inductively coupled plasma-optical emission spectroscopy) for MenA, DMAP assay for MenC and Resorcinol assay for MenW and MenY (Monsigny et al (1988) Anal. Biochem. 175, 525-530).

Often saccharides conjugated through a linker have higher incorporation of carrier protein than when directly linked to carrier protein. In a MenAC vaccine, for example, MenA saccharide may be conjugated to a carrier protein through a linker and MenC directly. In a MenCY vaccine, MenC may be conjugated through a linker and MenY directly. In a MenACWY vaccine Men A may be conjugated through a linker and MenCWY directly, or MenAC may be conjugated through a linker and MenWY directly.

Also disclosed is an immunogenic composition comprising at least 2 different saccharides conjugated separately to the same type of carrier protein (for instance DT, CRM197, Protein D, or TT), wherein one or more saccharide(s) is/are conjugated to the carrier protein wherein the saccharide:protein ratio (w/w) is between 1:2-1:5, and one or more different saccharides is/are conjugated to the carrier protein wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99.

For instance in a MenAC vaccine, MenA may be conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 1:2-1:5 and MenC conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 5:1-1:1.99. In a MenCY vaccine MenC may be conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 1:2-1:5 and MenY conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 5:1-1:1.99. In a MenACWY vaccine, MenAC may be conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 1:2-1:5 and MenWY conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 5:1-1:1.99., or MenA may be conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 1:2-1:5 and MenCWY conjugated to the carrier protein with a saccharide:protein ratio (w/w) between 5:1-1:1.99.

The present invention also provides:

a vaccine comprising the immunogenic composition of the invention and a pharmaceutically acceptable excipient;
a process for making the vaccine of the invention comprising the step of mixing the immunogenic composition of the invention with a pharmaceutically acceptable excipient; and
an immunogenic composition of the invention for use in the treatment or prevention of disease caused by Neisseria meningitidis infection.

Also disclosed is a method of immunising a human host against disease caused by Neisseria meningitidis comprising administering to the host an immunoprotective dose of the immunogenic composition or vaccine of the invention.

Description of figures

Figure 1

- A - Bar chart showing GMC responses in an anti-MenY ELISA. ENYTT012 is a MenY-TT conjugate prepared from native MenY polysaccharide. ENYTT014 is a MenY-TT conjugate prepared from microfluidised MenY polysaccharide which had undergone 40 cycles of microfluidisation. ENYTT015bis is a MenY-TT conjugate prepared from microfluidised MenY polysaccharide which had undergone 20 cycles of microfluidisation.
- B - Bar chart showing GMT responses in an anti-MenY SBA assay. ENYTT012 is a MenY-TT conjugate prepared from native MenY polysaccharide. ENYTT014 is a MenY-TT conjugate prepared from microfluidised MenY polysaccharide which had undergone 40 cycles of microfluidisation. ENYTT015bis is a MenY-TT conjugate prepared from microfluidised MenY polysaccharide which had undergone 20 cycles of microfluidisation.

Detailed description

The present invention provides an immunogenic composition comprising N. meningitidis serogroup A capsular saccharide (MenA), N. meningitidis serogroup C capsular saccharide (MenC), N. meningitidis serogroup Y capsular saccharide (MenY) and N. meningitidis serogroup W capsular saccharide (MenW) conjugated separately to the same type of carrier protein, wherein:

(a) MenA or MenA and MenC are conjugated to the carrier protein via a carboxyl group on the protein carrier and an ADH linker, wherein the or each capsular saccharide(s) conjugated via the ADH linker is/are conjugated to the linker with CDAP chemistry and the carrier protein is conjugated to the ADH linker with EDAC chemistry, wherein the saccharide:protein ratio (w/w) is between 1:2-1:5;
(b) the N. meningitidis saccharides from MenC, MenY and MenW distinct from (a), are conjugated to the carrier protein via an amino group on the protein carrier, wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99; and
(c) the carrier protein is TT

The immunogenic composition comprises MenW saccharide, wherein the ratio of Men W saccharide to carrier protein is between 5:1-1:1.99, for instance between 2:1-1:1.99, 1.5:1-1:1.8, 1:1-1:1.7, 1:1.2-1:1.6, or 1:1.4-1:1.5 (w/w). The immunogenic composition comprises MenY saccharide, wherein the ratio of Men Y saccharide to carrier protein is between 5:1-1:1.99, for instance between 2:1-1:1.99, 1.5:1-1:1.9, 1:1-1:1.8, 1:1.1-1:1.6, or 1:1.3-1:1.4 (w/w). The immunogenic composition comprises MenA saccharide, wherein the ratio of Men A saccharide to carrier protein is between 1:2-1:5, for instance between 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w). In a further aspect the immunogenic composition comprises MenC saccharide, wherein the ratio of Men C saccharide to carrier protein is between 5:1-1:1.99, for instance between 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w), or between 1:2-1:5, for instance between 1:2.5-1:4.5, 1:2.7-1:4.3, 1:3-1:4, or 1:3.3-1:3.5 (w/w).

More specifically, the first group may consist of MenA and MenC, and the second group consist of MenC, MenY and MenW. Particular immunogenic compositions disclosed are those comprising: MenA capsular saccharide wherein the ratio of Men A saccharide to carrier protein is between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w) [which is conjugated through an ADH linker to the carrier protein] and MenC capsular saccharide wherein the ratio of Men C saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w) [which is directly conjugated to the carrier protein]; MenC capsular saccharide wherein the ratio of Men C saccharide to carrier protein is between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w) [which is conjugated through a linker to the carrier protein] and MenY capsular saccharide wherein the ratio of Men Y saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w) [which is directly conjugated to the carrier protein]; MenA and MenC capsular saccharides wherein the ratio of Men A and C saccharide to carrier protein(s) is between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w) [and which are conjugated through a linker to the carrier protein(s)] and MenY and Men W capsular saccharides wherein the ratio of Men Y and W saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w) [and which are directly conjugated to the carrier protein(s)]; MenA capsular saccharide wherein the ratio of Men A saccharide to carrier protein is between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w) [which is conjugated through a linker to the carrier protein] and MenC, MenY and Men W capsular saccharides wherein the ratio of Men Y and W and C saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w) [and which are directly conjugated to the carrier protein(s)]. In any of these embodiments a Hib conjugate may also be included, which is linked to a carrier protein (see list of carriers above and below, for example TT, and for saccharide:protein ratios) directly or through a linker.

The term "saccharide" throughout this specification may indicate polysaccharide or oligosaccharide and includes both. Polysaccharides are isolated from bacteria or isolated from bacteria and sized to some degree by known methods (see for example EP497524 and EP497525 ) and optionally by microfluidisation. Polysaccharides can be sized in order to reduce viscosity in polysaccharide samples and/or to improve filterability for conjugated products. Oligosaccharides have a low number of repeat units (typically 5-30 repeat units) and are typically hydrolysed polysaccharides.

Each N. meningitidis (and/or Hib) capsular saccharide may be conjugated to TT carrier protein independently. In one instance Hib is also conjugated to TT carrier protein. The saccharides could be conjugated to the same molecule of the protein carrier. The saccharides may each be separately conjugated to different molecules of the TT protein carrier (each molecule of protein carrier only having one type of saccharide conjugated to it).

Also disclosed is an immunogenic composition comprising at least 2 different saccharides conjugated separately to the same type of carrier protein, wherein one or more saccharide(s) is/are conjugated to the carrier protein wherein the saccharide:protein ratio (w/w) is between 1:2-1:5 [a high ratio], and one or more different saccharides is/are conjugated to the carrier protein wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99 [a low ratio].

By "conjugated separately to the same type of carrier protein" it is meant that the saccharides are conjugated to the same carrier individually (i.e. different saccharides are not conjugated to the same molecule of the same protein carrier).

The N. meningitidis capsular saccharide(s) are all conjugated to TTcarrier protein.

The high ratio (1:2-1:5) and low ratio (5:1-1:1.99) saccharides may further comprise saccharides selected from a group consisting of: H. influenzae type b capsular saccharide (Hib), Group B Streptococcus group I capsular saccharide, Group B Streptococcus group II capsular saccharide, Group B Streptococcus group III capsular saccharide, Group B Streptococcus group IV capsular saccharide, Group B Streptococcus group V capsular saccharide, Staphylococcus aureus type 5 capsular saccharide, Staphylococcus aureus type 8 capsular saccharide, Vi saccharide from Salmonella typhi, N. meningitidis LPS (such as L3 and/or L2), M. catarrhalis LPS, H. influenzae LPS, and from any of the capsular pneumococcal saccharides such as from serotype: 1, 2, 3, 4, 5, 6A, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F or 33F.

In one embodiment, MenC is a high ratio saccharide; in another MenC a low ratio saccharide; in another instance Hib a high ratio saccharide. Vaccines comprising MenA/C/W/Y may be high/high/low/low ratio, respectively, and vaccines comprising MenA/C/W/Y may be high/low/low/low ratio, respectively.

General considerations in the aspects of the invention

The N. meningitidis saccharides of the invention are conjugated to TT carrier protein. Other saccharides (in particular the Hib capsular saccharide) that can also be included in pharmaceutical (immunogenic) compositions are conjugated to a carrier protein such as tetanus toxoid (TT), tetanus toxoid fragment C, non-toxic mutants of tetanus toxin [note all such variants of TT are considered to be the same type of carrier protein for the purposes of this invention], diphtheria toxoid (DT), CRM197, other non-toxic mutants of diphtheria toxin [such as CRM176, CRM 197, CRM228, CRM 45 (Uchida et al J. Biol. Chem. 218; 3838-3844, 1973); CRM 9, CRM 45, CRM102, CRM 103 and CRM107 and other mutations described by Nicholls and Youle in Genetically Engineered Toxins, Ed: Frankel, Maecel Dekker Inc, 1992; deletion or mutation of Glu-148 to Asp, Gln or Ser and/or Ala 158 to Gly and other mutations disclosed in US 4709017 or US 4950740 ; mutation of at least one or more residues Lys 516, Lys 526, Phe 530 and/or Lys 534 and other mutations disclosed in US 5917017 or US 6455673 ; or fragment disclosed in US 5843711 ] (note all such variants of DT are considered to be the same type of carrier protein for the purposes of this invention), pneumococcal pneumolysin (Kuo et al (1995) Infect Immun 63; 2706-13), OMPC (meningococcal outer membrane protein - usually extracted from N. meningitidis serogroup B - EP0372501 ), synthetic peptides ( EP0378881 , EP0427347 ), heat shock proteins ( WO 93/17712 , WO 94/03208 ), pertussis proteins ( WO 98/58668 , EP0471177 ), cytokines, lymphokines, growth factors or hormones ( WO 91/01146 ), artificial proteins comprising multiple human CD4+ T cell epitopes from various pathogen derived antigens (Falugi et al (2001) Eur J Immunol 31; 3816-3824) such as N19 protein (Baraldoi et al (2004) Infect Immun 72; 4884-7) pneumococcal surface protein PspA ( WO 02/091998 ), iron uptake proteins ( WO 01/72337 ), toxin A or B of C. difficile ( WO 00/61761 ) or Protein D ( EP594610 and WO 00/56360 ).

Optionally Hib is also conjugated to TT.

In an instance, the immunogenic composition comprises a Hib saccharide conjugated to a carrier protein selected from the group consisting of TT, DT, CRM197, fragment C of TT and protein D.

The immunogenic composition optionally comprises a Hib saccharide conjugate having a ratio of Hib to carrier protein of between 1:5 and 5:1; 1:2 and 2:1; 1:1 and 1:4; 1:2 and 1:3.5; or around or exactly 1:2.5 or 1:3 (w/w).

In an immunogenic composition of the invention MenA or MenA and MenC are conjugated to TT carrier protein via an ADH linker. In an instance, in the immunogenic composition the Hib saccharide is conjugated to the carrier protein via a linker, for instance a bifunctional linker. The linker is optionally heterobifunctional or homobifunctional, having for example a reactive amino group and a reactive carboxylic acid group, 2 reactive amino groups or two reactive carboxylic acid groups. The linker has for example between 4 and 20, 4 and 12, 5 and 10 carbon atoms. A possible linker is ADH. Other linkers include B-propionamido ( WO 00/10599 ), nitrophenyl-ethylamine (Gever et al (1979) Med. Microbiol. Immunol. 165; 171-288), haloalkyl halides ( US4057685 ), glycosidic linkages ( US4673574 , US4808700 ), hexane diamine and 6-aminocaproic acid ( US4459286 ).

MenA or MenA and MenC are conjugated to the carrier protein via a carboxyl group on the protein carrier and an ADH linker, wherein the or each capsular saccharide(s) conjugated via the ADH linker is/are conjugated to the linker with CDAP chemistry and the carrier protein is conjugated to the ADH linker with EDAC chemistry, wherein the saccharide:protein ratio (w/w) is between 1:2-1:5. The remaining MenC, MenY and MenW not conjugated via linker are conjugated to the carrier protein via an amino group on the protein carrier, wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99. The conjugation method for MenC, MenY and MenW relies on activation of the saccharide with 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP) to form a cyanate ester. The activated saccharide may thus be coupled directly or via a spacer (linker) group to an amino group on the carrier protein. For example, the spacer could be cystamine or cysteamine to give a thiolated polysaccharide which could be coupled to the carrier via a thioether linkage obtained after reaction with a maleimide-activated carrier protein (for example using GMBS) or a holoacetylated carrier protein (for example using iodoacetimide or N-succinimidyl bromoacetatebromoacetate). For MenA or MenA and MenC, the cyanate ester (made by CDAP chemistry) is coupled with ADH and the amino-derivatised saccharide is conjugated to the carrier protein using using carbodiimide (EDAC) chemistry via a carboxyl group on the protein carrier. Such conjugates are described in PCT published application WO 93/15760 Uniformed Services University and WO 95/08348 and WO 96/29094 .

The conjugates can also be prepared by direct reductive amination methods as described in US 4365170 (Jennings ) and US 4673574 (Anderson ). Other methods are described in EP-0-161-188 , EP-208375 and EP-0-477508 .

A further method involves the coupling of a cyanogen bromide (or CDAP) activated saccharide derivatised with adipic acid dihydrazide (ADH) to the protein carrier by Carbodiimide condensation (Chu C. et al Infect. Immunity, 1983 245 256), for example using EDAC.

The Hib capsular saccharide is conjugated to the linker first before the linker is conjugated to the carrier protein. Alternatively the linker may be conjugated to the carrier before conjugation to the saccharide.

In general the following types of chemical groups on a protein carrier can be used for coupling / conjugation:

A) Carboxyl (for instance via aspartic acid or glutamic acid). In one embodiment this group is linked to amino groups on saccharides directly or to an amino group on a linker with carbodiimide chemistry e.g. with EDAC.
B) Amino group (for instance via lysine). In one embodiment this group is linked to carboxyl groups on saccharides directly or to a carboxyl group on a linker with carbodiimide chemistry e.g. with EDAC. In another embodiment this group is linked to hydroxyl groups activated with CDAP or CNBr on saccharides directly or to such groups on a linker; to saccharides or linkers having an aldehyde group; to saccharides or linkers having a succinimide ester group.
C) Sulphydryl (for instance via cysteine). In one embodiment this group is linked to a bromo or chloro acetylated saccharide or linker with maleimide chemistry. In one embodiment this group is activated/modified with bis diazobenzidine.
D) Hydroxyl group (for instance via tyrosine). In one embodiment this group is activated/modified with bis diazobenzidine.
E) Imidazolyl group (for instance via histidine). In one embodiment this group is activated/modified with bis diazobenzidine.
F) Guanidyl group (for instance via arginine).
G) Indolyl group (for instance via tryptophan).

On a saccharide, in general the following groups can be used for a coupling: OH, COOH or NH2. Aldehyde groups can be generated after different treatments known in the art such as: periodate, acid hydrolysis, hydrogen peroxide, etc.

Direct coupling approaches:

Saccharide-OH + CNBr or CDAP -----> cyanate ester + NH2-Prot ----> conjugate Saccharide-aldehyde + NH2-Prot ----> Schiff base + NaCNBH3 ----> conjugate Saccharide-COOH + NH2-Prot + EDAC ----> conjugate Saccharide-NH2 + COOH-Prot + EDAC ----> conjugate

Indirect coupling via spacer (linker) approaches:

Saccharide-OH + CNBr or CDAP ---> cyanate ester + NH2----NH2 ----> saccharide-NH2 + COOH-Prot + EDAC -----> conjugate Saccharide-OH + CNBr or CDAP ----> cyanate ester + NH2-----SH -----> saccharide----SH + SH-Prot (native Protein with an exposed cysteine or obtained after modification of amino groups of the protein by SPDP for instance) -----> saccharide-S-S-Prot Saccharide-OH + CNBr or CDAP ---> cyanate ester + NH2----SH -------> saccharide----SH + maleimide-Prot (modification of amino groups) ----> conjugate Saccharide-COOH + EDAC + NH2-----NH2 ---> saccharide------NH2 + EDAC + COOH-Prot ----> conjugate Saccharide-COOH + EDAC+ NH2----SH -----> saccharide----SH + SH-Prot (native Protein with an exposed cysteine or obtained after modification of amino groups of the protein by SPDP for instance) -----> saccharide-S-S-Prot Saccharide-COOH + EDAC+ NH2----SH -----> saccharide----SH + maleimide-Prot (modification of amino groups) ----> conjugate Saccharide-Aldehyde + NH2-----NH2 ----> saccharide---NH2 + EDAC + COOH-Prot ----> conjugate Note: instead of EDAC above, any suitable carbodiimide may be used.

In summary, the types of protein carrier chemical group that may be generally used for coupling with a saccharide are amino groups (for instance on lysine residues), COOH groups (for instance on aspartic and glutamic acid residues) and SH groups (if accessible) (for instance on cysteine residues. An immunogenic composition of the invention is one comprising N. meningitidis serogroup A capsular saccharide (MenA), N. meningitidis serogroup C capsular saccharide (MenC), N. meningitidis serogroup Y capsular saccharide (MenY) and N. meningitidis serogroup W capsular saccharide (MenW) conjugated separately to the same type of carrier protein, wherein:

In an instance, the Hib saccharide, where present, is conjugated to the carrier protein using CNBr, or CDAP, or a combination of CDAP and carbodiimide chemistry (such as EDAC), or a combination of CNBr and carbodiimide chemistry (such as EDAC). Optionally Hib is conjugated using CNBr and carbodiimide chemistry, optionally EDAC. For example, CNBr is used to join the saccharide and linker and then carbodiimide chemistry is used to join linker to the protein carrier.

In an embodiment, MenA; or MenA and MenC is conjugated to a carrier protein (for example tetanus toxoid) via a linker.

MenA or MenA and MenC are conjugated to TT carrier protein via an ADH linker using CDAP and EDAC. Optionally the conjugation via a linker results in a ratio of saccharide to carrier protein of of between 1:0.5 and 1:6; 1:1 and 1:5 or 1:2 and 1:4, for MenA; or MenA and MenC.

A further consideration in a combination vaccine comprising various saccharides conjugated to the same carrier is the issue of carrier immune suppression: too much carrier may be used and the immune response may be dampened. With a uniform approach to conjugation the carrier will present a similar blend of B- and T- cell epitopes to the immune system. However if conjugation takes place at different chemical groups within the carrier protein for one saccharide versus another, the protein carriers are likely to be different to some extent in how they present themselves to the immune system.

Accordingly also disclosed is an immunogenic composition comprising at least 2 different saccharides conjugated separately to the same type of carrier protein (for instance tetanus toxoid), wherein one or more saccharide(s) is/are conjugated to the carrier protein via a first type of chemical group on the protein carrier, and one or more saccharide(s) is/are conjugated to the carrier protein via a second (different) type of chemical group on the protein carrier.

The first and second types of chemical group may be present in the protein carrier on a mutually exclusive first and second set of amino acids of the protein carrier (for instance certain aspartic acid / glutamic acid residues in one set and certain lysine/arginine residues in the second). One saccharide may be conjugated to a carboxyl group on the carrier, and another on an amino group for instance. Such conjugation may involve conjugation on separate B- and/or T-cell epitopes for each different conjugate.

For instance in a MenAC vaccine, MenA may be linked to a first type of chemical group (such as carboxyl) on the carrier protein and MenC linked to a second (such as amino). In a MenCY vaccine MenC may be linked to a first type of chemical group (such as carboxyl) on the carrier protein and MenY linked to a second (such as amino). In a MenACWY vaccine, MenAC may be linked to a first type of chemical group (such as carboxyl) on the carrier protein and MenWY linked to a second (such as amino), or MenA may be linked to a first type of chemical group (such as carboxyl) on the carrier protein and MenCWY linked to a second (such as amino).

In one instance the 2 conjugates may involve the same type of saccharide linked to the same type of carrier, but by different conjugation chemistries. In an alternative instance 2 different saccharides are conjugated to different groups on the protein carrier. By "conjugated separately to the same type of carrier protein" it is meant that the saccharides are conjugated to the same carrier individually (i.e. both first and second chemical groups on the same molecule of protein carrier are not used to conjugate the saccharide moieties, rather the first chemical group on a first aliquot of protein carrier is used in respect of conjugating a first saccharide, and a second chemical group on a second aliquot of the protein carrier is used in respect of conjugating a second saccharide).

In one instance the first and second type of chemical group on the protein carrier are present on separate B- and/or T-cell epitopes on the carrier protein. That is, they are present on a different set of B- and/or T-cell epitopes from each other. To predict B-cell epitopes for a carrier known methods may be used such as either or both of the following two methods: 2D-structure prediction and/or antigenic index prediction. 2D-structure prediction can be made using the PSIPRED program (from David Jones, Brunel Bioinformatics Group, Dept. Biological Sciences, Brunel University, Uxbridge UB8 3PH, UK). The antigenic index can be calculated on the basis of the method described by Jameson and Wolf (CABIOS 4:181-186 [1988]). The parameter used in this program are the antigenic index and the minimal length for an antigenic peptide. An antigenic index of 0.9 for a minimum of 5 consecutive amino acids can be used as the thresholds in the program. T-helper cell epitopes are peptides bound to HLA class II molecules and recognized by T-helper cells. The prediction of useful T-helper cell epitopes can be based on known techniques, such as the TEPITOPE method describe by Sturniolo at al. (Nature Biotech. 17: 555-561 [1999]).

The first and second chemical groups present on the protein carrier are optionally different from each other and are ideally natural chemical groups that may be readily used for conjugation purposes. They may be selected independently from the group consisting of: carboxyl groups, amino groups, sulphydryl groups, Hydroxyl groups, Imidazolyl groups, Guanidyl groups, and Indolyl groups. In one instance the first chemical group is carboxyl and the second is amino, or vice versa. These groups are explained in greater detail above.

In a specific instance the immunogenic composition comprises at least 2 different N. meningitidis capsular saccharides, wherein one or more is/are selected from a first group consisting of MenA and MenC which is/are conjugated to the carrier protein via the first type of chemical group on the protein carrier (for instance carboxyl), and one or more different saccharides is/are selected from a second group consisting of MenC, MenY and MenW which is/are conjugated to the carrier protein via the second type of chemical group on the protein carrier (for instance amino).

In a further instance the immunogenic composition of the invention comprises MenA conjugated via the first type of chemical group (for instance carboxyl), and MenC conjugated via the second type of chemical group (for instance amino).

In another instance the immunogenic composition comprises MenC conjugated via the first type of chemical group (for instance carboxyl), and MenY conjugated via the second type of chemical group (for instance amino).

In another instance the immunogenic composition comprises MenA conjugated via the first type of chemical group (for instance carboxyl), and MenC, MenY and MenW conjugated via the second type of chemical group (for instance amino).

In another instance the immunogenic composition comprises MenA and MenC conjugated via the first type of chemical group (for instance carboxyl), and MenY and MenW conjugated via the second type of chemical group (for instance amino).

In any of the above instances Hib may also be present also conjugated to the same type of protein carrier. Hib may be conjugated to the carrier by the first or second type of chemical group. In one embodiment it is conjugated via a carboxyl group.

In an embodiment, the MenA capsular saccharide is at least partially O-acetylated such that at least 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units are O-acetylated at least one position. O-acetylation is for example present at least at the O-3 position of at least 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units.

In an embodiment, the MenC capsular saccharide is at least partially O-acetylated such that at least 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of (α2 →9)-linked NeuNAc repeat units are O-acetylated at least one or two positions. O-acetylation is for example present at the O-7 and/or O-8 position of at least 30%. 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units.

In an embodiment, the MenW capsular saccharide is at least partially O-acetylated such that at least 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units are O-acetylated at least one or two positions. O-acetylation is for example present at the O-7 and/or O-9 position of at least 30%. 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units.

In an embodiment, the MenY capsular saccharide is at least partially O-acetylated such that at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units are O-acetylated at least one or two positions. O-acetylation is present at the 7 and/or 9 position of at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% of the repeat units.

The percentage of O-acetylation refers to the percentage of the repeat units containing O-acetylation. This may be measured in the saccharide prior to conjugate and/or after conjugation.

The immunogenic composition of the invention optionally comprise one or more saccharide conjugates wherein the average size of each saccharide before conjugation is above 50kDa, 75kDa, 100kDa, 110kDa, 120kDa or 130kDa. In one embodiment the conjugate post conjugation should be readily filterable through a 0.2 micron filter such that a yield of more than 50, 60, 70, 80, 90 or 95% is obtained post filtration compared with the pre filtration sample.

In particular, the immunogenic composition of the invention comprises N. meningitidis capsular saccharides from serogroups A, C, W and Y conjugated to a carrier protein, wherein the average size (weight-average molecular weight; Mw) of at least one, two, three or four or each N. meningitidis saccharide is above 50kDa, 60kDa, 75kDa, 100kDa, 110kDa, 120kDa or 130kDa.

The immunogenic composition may comprise N. meningitidis capsular saccharides from at least one, two, three or four of serogroups A, C, W and Y conjugated to a carrier protein, wherein at least one, two, three or four or each N. meningitidis saccharide is either a native saccharide or is sized by a factor up to x1.5, x2, x3, x4, x5, x6, x7, x8, x9 or x10 relative to the weight average molecular weight of the native polysaccharide.

For the purposes of the invention, "native polysaccharide" refers to a saccharide that has not been subjected to a process, the purpose of which is to reduce the size of the saccharide. A polysaccharide can become slightly reduced in size during normal purification procedures. Such a saccharide is still native. Only if the polysaccharide has been subjected to sizing techniques would the polysaccharide not be considered native.

For the purposes of the invention, "sized by a factor up to x2" means that the saccharide is subject to a process intended to reduce the size of the saccharide but to retain a size more than half the size of the native polysaccharide. X3, x4 etc. are to be interpreted in the same way i.e. the saccharide is subject to a process intended to reduce the size of the polysaccharide but to retain a size more than a third, a quarter etc. the size of the native polysaccharide.

In an aspect of the invention, the immunogenic composition comprises N. meningitidis capsular saccharides from serogroups A, C, W and Y conjugated to a carrier protein, wherein at least one, two, three or four or each N. meningitidis saccharide is native polysaccharide.

In an aspect of the invention, the immunogenic composition comprises N. meningitidis capsular saccharides from serogroups A, C, W and Y conjugated to a carrier protein, wherein at least one, two, three or four or each N. meningitidis saccharide is sized by a factor up to x2, x3, x4, x5, x6, x7, x8, x9 or x10.

In an embodiment, the average size of at least one, two, three, four or each N. meningitidis saccharide is between 50KDa and 1500kDa, 50kDa and 500kDa, 50 kDa and 300 KDa, 101kDa and 1500kDa, 101kDa and 500kDa, 101kDa and 300kDa as determined by MALLS.

In an embodiment, the MenA saccharide has a molecular weight of 50-500kDa, 50-100kDa, 100-500kDa, 55-90KDa, 60-70kDa or 70-80kDa or 60-80kDa by MALLS.

In an embodiment, the MenC saccharide has a molecular weight of 100-200kDa, 50-100kDa, 100-150kDa, 101-130kDa, 150-210kDa or 180-210kDa by MALLS.

In an embodiment the MenY saccharide has a molecular weight of 60-190kDa, 70-180kDa, 80-170kDa, 90-160kDa, 100-150kDa or 110-140kDa, 50-100kDa, 100-140kDa, 140-170kDa or 150-160kDa by MALLS.

In an embodiment the MenW saccharide has a molecular weight of 60-190kDa, 70-180kDa, 80-170kDa, 90-160kDa, 100-150kDa, 110-140kDa, 50-100kDa or 120-140kDa by MALLS.

The molecular weight or average molecular weight of a saccharide herein refers to the weight-average molecular weight (Mw) of the saccharide measured prior to conjugation and is measured by MALLS.

The MALLS technique is well known in the art and is typically carried out as described in example 2. For MALLS analysis of meningococcal saccharides, two columns (TSKG6000 and 5000PWxl TOSOH Bioscience) may be used in combination and the saccharides are eluted in water. Saccharides are detected using a light scattering detector (for instance Wyatt Dawn DSP equipped with a 10mW argon laser at 488nm) and an inferometric refractometer (for instance Wyatt Otilab DSP equipped with a P100 cell and a red filter at 498nm).

In an embodiment the N. meningitidis saccharides are native polysaccharides or native polysaccharides which have reduced in size during a normal extraction process.

In an embodiment, the N. meningitidis saccharides are sized by mechanical cleavage, for instance by microfluidisation or sonication. Microfluidisation and sonication have the advantage of decreasing the size of the larger native polysaccharides sufficiently to provide a filterable conjugate. Sizing is by a factor of no more than x20, x10, x8, x6, x5, x4, x3 or x2.

In an embodiment, the immunogenic composition comprises N. meningitidis conjugates that are made from a mixture of native polysaccharides and saccharides that are sized by a factor of no more than x20. For example, saccharides from MenC and/or MenA are native. For example, saccharides from MenY and/or MenW are sized by a factor of no more than x20, x10, x8, x6, x5, x4, x3 or x2. For example, an immunogenic composition contains a conjugate made from MenY and/or MenW and/or MenC and/or MenA which is sized by a factor of no more then x10 and/or is microfluidised. For example, an immunogenic composition contains a conjugate made from native MenA and/or MenC and/or MenW and/or MenY. For example, an immunogenic composition comprises a conjugate made from native MenC. For example, an immunogenic composition comprises a conjugate made from native MenC and MenA which is sized by a factor of no more then x10 and/or is microfluidised. For example, an immunogenic composition comprises a conjugate made from native MenC and MenY which is sized by a factor of no more then x10 and/or is microfluidised.

In an embodiment, the polydispersity of the saccharide is 1-1.5, 1-1.3, 1-1.2, 1-1.1 or 1-1.05 and after conjugation to a carrier protein, the polydispersity of the conjugate is 1.0-2,5, 1.0-2.0. 1.0-1.5, 1.0-1.2, 1.5-2.5, 1.7-2.2 or 1.5-2.0. All polydispersity measurements are by MALLS.

Saccharides are optionally sized up to 1.5, 2, 4, 6, 8, 10, 12, 14, 16, 18 or 20 times from the size of the polysaccharide isolated from bacteria.

In one embodiment each N. meningitidis saccharide is either a native polysaccharide or is sized by a factor of no more than x10. In a further embodiment each N. meningitidis capsular saccharide is a native polysaccharide. In a further embodiment at least one, two, three or four N. meningitidis capsular saccharide(s) is sized by microfluidization. In a further embodiment each N. meningitidis capsular saccharide is sized by a factor of no more than x10. In a further embodiment the N. meningitidis conjugates are made from a mixture of native polysaccharides and saccharides that are sized by a factor of no more than x10. In a further embodiment the capsular saccharide from serogroup Y is sized by a factor of no more than x10. In a further embodiment capsular saccharides from serogroups A and C are native polysaccharides and saccharides from serogroups W135 and Y are sized by a factor of no more than x10. In a further embodiment the average size of each N. meningitidis capular saccharide is between 50 kDa and 300 KDa or 50kDa and 200kDa. In a further embodiment the immunogenic composition comprises a MenA capsular saccharide having an average size of above 50kDa, 75kDa, 100kDa or an average size of between 50-100kDa or 55-90KDa or 60-80kDa. In a further embodiment the immunogenic composition comprises a MenC capsular saccharide having an average size of above 50kDa, 75kDa, 100kDa or between 100-200kDa, 100-150kDa, 80-120kDa , 90-110kDa, 150-200kDa, 120-240kDa, 140-220kDa, 160-200kDa or 190-200kDa. In a further embodiment the immunogenic composition comprises a MenY capsular saccharide, having an average size of above 50kDa, 75kDa, 100kDa or between 60-190kDa or 70-180kDa or 80-170kDa or 90-160kDa or 100-150kDa , 110-145kDa or 120-140kDa. In a further embodiment the immunogenic composition comprises a MenW capsular saccharide having an average size of above 50kDa, 75kDa, 100kDa or between 60-190kDa or 70-180kDa or 80-170kDa or 90-160kDa or 100-150kDa, 140-180kDa, 150-170kDa or 110-140kDa.

The immunogenic composition of the invention may comprise a H. influenzae b capsular saccharide (Hib) conjugated to a carrier protein. This may be conjugated to a carrier protein selected from the group consisting of TT, DT, CRM197, fragment C of TT and protein D, for instance TT. The Hib saccharide may be conjugated to the same carrier protein as for at least one, two, three or all of the N. meningitidis capsular saccharide conjugates, for instance TT. The ratio of Hib to carrier protein in the Hib capsular saccharide conjugate may be between 1:5 and 5:1 (w/w), for instance between 1:1 and 1:4, 1:2 and 1:3.5 or around 1:3 (w/w). The Hib capsular saccharide may be conjugated to the carrier protein via a linker (see above). The linker may be bifunctional (with two reactive amino groups, such as ADH, or two reactive carboxylic acid groups, or a reactive amino group at one end and a reactive carboxylic acid group at the other end). It may have between 4 and 12 carbon atoms. Hib saccharide may be conjugated to the carrier protein or linker using CNBr or CDAP. The carrier protein may be conjugated to the Hib saccharide via the linker using a method comprising carbodiimide chemistry, optionally EDAC chemistry (thus using the carboxyl chemical group on the carrier). The dose of the Hib saccharide conjugate may be between 0.1 and 9µg, 1 and 5µg or 2 and 3µg of saccharide.

In a further instance, the immunogenic composition comprises a Hib saccharide conjugate and at least two N. meningitidis saccharide conjugates wherein the Hib conjugate is present in a lower saccharide dose than the mean saccharide dose of the at least two N. meningitidis saccharide conjugates. Alternatively, the Hib conjugate is present in a lower saccharide dose than the saccharide dose of each of the at least two N. meningitidis saccharide conjugates. For example, the dose of the Hib conjugate may be at least 10%, 20%, 30%, 40%, 50%, 60%, 70% or 80% lower than the mean or lowest saccharide dose of the at least two further N. meningitidis saccharide conjugates.

The mean dose is determined by adding the doses of all the further saccharides and dividing by the number of further saccharides. Further saccharides are all the saccharides within the immunogenic composition apart from Hib and can include N. meningitidis capsular saccharides. The "dose" is in the amount of immunogenic composition or vaccine that is administered to a human.

A Hib saccharide is the polyribosyl phosphate (PRP) capsular polysaccharide of Haemophilus influenzae type b or an oligosaccharide derived therefrom.

"At least two further bacterial saccharide conjugates" is to be taken to mean two further bacterial saccharide conjugates in addition to a Hib conjugate. The two further bacterial conjugates may include N. meningitidis capular saccharide conjugates.

The immunogenic compositions of the invention may comprise further saccharide conjugates derived from one or more of Streptococcus pneumoniae, Group A Streptococci, Group B Streptococci, S. typhi, Staphylococcus aureus or Staphylococcus epidermidis. A further instance comprises capsular saccharides derived from Streptococcus pneumoniae. The pneumococcal capsular saccharide antigens are optionally selected from serotypes 1, 2, 3, 4, 5, 6A, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F (optionally from serotypes 1, 3, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F). A further instance comprises the Type 5, Type 8 or 336 capsular saccharides of Staphylococcus aureus. A further instance comprises the Type I, Type II or Type III capsular saccharides of Staphylococcus epidermidis. A further instance comprises the Vi saccharide from S. typhi. A further instancecomprises the Type la, Type Ic, Type II, Type III or Type V capsular saccharides of Group B streptococcus. A further instancecomprises the capsular saccharides of Group A streptococcus, optionally further comprising at least one M protein and more optionally multiple types of M protein.

The immunogenic compositions may also comprise a DTPa or DTPw vaccine (for instance one containing DT, TT, and either a whole cell pertussis (Pw) vaccine or an acellular pertussis (Pa) vaccine (comprising for instance pertussis toxoid, FHA, pertactin, and, optionally agglutinogins 2 and 3). Such combinations may also comprise a vaccine against hepatitis B (for instance it may comprise hepatitis B surface antigen [HepB], optionally adsorbed onto aluminium phosphate). In one instance the immunogenic composition comprises a DTPwHepBHibMenAC vaccine where the MenAC component is as described herein.

In an instance, the immunogenic compositionfurther comprises an antigen from N. meningitidis serogroup B. The antigen is optionally a capsular polysaccharide from N. meningitidis serogroup B (MenB) or a sized polysaccharide or oligosaccharide derived therefrom, which may be conjugated to a protein carrier. The antigen is optionally an outer membrane vesicle preparation from N. meningitidis serogroup B as described in EP301992 , WO 01/09350 , WO 04/14417 , WO 04/14418 and WO 04/14419 .

In general, the immunogenic composition of the invention may comprise a dose of each saccharide conjugate between 2 and 20µg, 3 and 10µg or 4 and 7µg of saccharide.

In an embodiment, the immunogenic composition of the invention contains each N. meningitidis capsular saccharide at a dose of between 0.1-20µg; 1-10µg; 2-10µg, 2.5-5µg, around or exactly 5µg; or around or exactly 2.5µg.

In an instance, the immunogenic composition for example contains the Hib saccharide conjugate at a saccharide dose between 0.1 and 9µg; 1 and 5µg or 2 and 3µg or around or exactly 2.5µg. In a further instance the immunogenic composition for example contains the Hib saccharide conjugate at a saccharide dose between 0.1 and 9µg; 1 and 5µg or 2 and 3µg or around or exactly 2.5µg and each of the N. meningitidis polysaccharide conjugates at a saccharide dose of between 2 and 20µg, 3 and 10µg, or between 4 and 7µg or around or exactly 5µg.

"Around" or "approximately" are defined as within 10% more or less of the given figure for the purposes of the invention.

In an instance, the immunogenic composition may contain a saccharide dose of the Hib saccharide conjugate which is for example less than 90%, 80%, 75%, 70%, 60%, 50%, 40%, 30%, 20% or 10% of the mean saccharide dose of at least two, three, four or each of the N. meningitidis saccharide conjugates. The saccharide dose of the Hib saccharide is for example between 20% and 60%, 30% and 60%, 40% and 60% or around or exactly 50% of the mean saccharide dose of at least two, three, four or each of the N. meningitidis saccharide conjugates.

In an instance, the immunogenic composition contains a saccharide dose of the Hib saccharide conjugate which is for example less than 90%, 80%, 75%, 70%, 60%, 50%, 40%, 30%, 20% or 10% of the lowest saccharide dose of the at least two, three, four or each of the N. meningitidis saccharide conjugates. The saccharide dose of the Hib saccharide is for example between 20% and 60%, 30% and 60%, 40% and 60% or around or exactly 50% of the lowest saccharide dose of the at least two, three, four or each of the N. meningitidis saccharide conjugates.

In an embodiment of the invention, the saccharide dose of each of the at least two, three, four or each of the N. meningitidis saccharide conjugates is optionally the same, or approximately the same.

A further aspect of the invention is a vaccine comprising the immunogenic composition of the invention and a pharmaceutically acceptable excipient.

In an embodiment, the immunogenic composition of the invention is buffered at, or adjusted to, between pH 7.0 and 8.0, pH 7.2 and 7.6 or around or exactly pH 7.4.

The immunogenic composition or vaccines of the invention are optionally lyophilised in the presence of a stabilising agent for example a polyol such as sucrose or trehalose.

Optionally, the immunogenic composition or vaccine of the invention contains an amount of an adjuvant sufficient to enhance the immune response to the immunogen. Suitable adjuvants include, but are not limited to, aluminium salts (aluminium phosphate or aluminium hydroxide), squalene mixtures (SAF-1), muramyl peptide, saponin derivatives, mycobacterium cell wall preparations, monophosphoryl lipid A, mycolic acid derivatives, non-ionic block copolymer surfactants, Quil A, cholera toxin B subunit, polyphosphazene and derivatives, and immunostimulating complexes (ISCOMs) such as those described by Takahashi et al. (1990) Nature 344:873-875.

For the N. meningitidis or HibMen combinations discussed above, it may be advantageous not to use any aluminium salt adjuvant or any adjuvant at all.

As with all immunogenic compositions or vaccines, the immunologically effective amounts of the immunogens must be determined empirically. Factors to be considered include the immunogenicity, whether or not the immunogen will be complexed with or covalently attached to an adjuvant or carrier protein or other carrier, route of administrations and the number of immunising dosages to be administered.

The active agent can be present in varying concentrations in the pharmaceutical composition or vaccine of the invention. Typically, the minimum concentration of the substance is an amount necessary to achieve its intended use, while the maximum concentration is the maximum amount that will remain in solution or homogeneously suspended within the initial mixture. For instance, the minimum amount of a therapeutic agent is optionally one which will provide a single therapeutically effective dosage. For bioactive substances, the minimum concentration is an amount necessary for bioactivity upon reconstitution and the maximum concentration is at the point at which a homogeneous suspension cannot be maintained. In the case of single-dosed units, the amount is that of a single therapeutic application. Generally, it is expected that each dose will comprise 1-100µg of protein antigen, optionally 5-50µg or 5-25µg. Examples of doses of bacterial saccharides are 10-20µg, 5-10µg, 2.5-5µg or 1-2.5µg of saccharide in the conjugate.

The vaccine preparations of the present invention may be for use in methods to protect or treat a mammal (for example a human patient) susceptible to infection, by means of administering said vaccine via systemic or mucosal route. A human patient is optionally an infant (under 12 months), a toddler (12-24, 12-16 or 12-14 months), a child (2-12, 3-8 or 3-5 years) an adolescent (12-20, 14-20 or 15-19 years) or an adult. These administrations may include injection via the intramuscular, intraperitoneal, intradermal or subcutaneous routes; or via mucosal administration to the oral/alimentary, respiratory, genitourinary tracts. Intranasal administration of vaccines for the treatment of pneumonia or otitis media is preferred (as nasopharyngeal carriage of pneumococci can be more effectively prevented, thus attenuating infection at its earliest stage). Although the vaccine of the invention may be administered as a single dose, components thereof may also be co-administered together at the same time or at different times (for instance if saccharides are present in a vaccine these could be administered separately at the same time or 1-2 weeks after the administration of a bacterial protein vaccine for optimal coordination of the immune responses with respect to each other). In addition to a single route of administration, 2 different routes of administration may be used. For example, viral antigens may be administered ID (intradermal), whilst bacterial proteins may be administered IM (intramuscular) or IN (intranasal). If saccharides are present, they may be administered IM (or ID) and bacterial proteins may be administered IN (or ID). In addition, the vaccines of the invention may be administered IM for priming doses and IN for booster doses.

Vaccine preparation is generally described in Vaccine Design ("The subunit and adjuvant approach" (eds Powell M.F. & Newman M.J.) (1995) Plenum Press New York). Encapsulation within liposomes is described by Fullerton, US Patent 4,235,877 .

Also disclosed is a vaccine kit for concomitant or sequential administration comprising two multi-valent immunogenic compositions for conferring protection in a host against disease caused by Bordetella pertussis, Clostridium tetani, Corynebacterium diphtheriae and Neisseria meningitidis and optionally Haemophilus influenzae. For example, the kit optionally comprises a first container comprising one or more of:

tetanus toxoid (TT),
diphtheria toxoid (DT), and
whole cell or acellular pertussis components
and a second container comprising: an immunogenic composition of the invention as described above (for instance those comprising Men or HibMen saccharide conjugate combinations).

Also disclosed is a vaccine kit for concomitant or sequential administration comprising two multi-valent immunogenic compositions for conferring protection in a host against disease caused by Streptococcus pneumoniae and Neisseria meningitidis and optionally Haemophilus influenzae. For example, the kit optionally comprises a first container comprising:

one or more conjugates of a carrier protein and a capsular saccharide from Streptococcus pneumoniae [where the capsular saccharide is optionally from a pneumococcal serotype selected from the group consisting of 1, 2, 3, 4, 5, 6A, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F].
and a second container comprising: an immunogenic composition of the invention as described above (for instance those comprising Men or HibMen saccharide conjugate combinations). Examples of the Hib conjugate and the N. meningitidis polysaccharide conjugates are as described above.

Typically the Streptococcus pneumoniae vaccine in the vaccine kit (or in any of the immunogenic compositions of the invention described above) will comprise saccharide antigens (optionally conjugated), wherein the saccharides are derived from at least four serotypes of pneumococcus chosen from the group consisting of 1, 2, 3, 4, 5, 6A, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F. Optionally the four serotypes include 6B, 14, 19F and 23F. More optionally, at least 7 serotypes are included in the composition, for example those derived from serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F. Optionally more than 7 serotypes are included in the composition, for instance at least 10, 11, 12, 13 or 14 serotypes. For example the composition in one embodiment includes 10 or 11 capsular saccharides derived from serotypes 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F, and optionally 3 (all optionally conjugated). In an embodiment of the invention at least 13 saccharide antigens (optionally conjugated) are included, although further saccharide antigens, for example 23 valent (such as serotypes 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F), are also contemplated by the invention.

The pneumococcal saccharides are independently conjugated to any known carrier protein, for example CRM197, tetanus toxoid, diphtheria toxoid, protein D or any other carrier proteins as mentioned above.

Optionally, the vaccine kits comprise a third component. For example, the kit optionally comprises a first container comprising one or more of:

tetanus toxoid (TT),
diphtheria toxoid (DT), and
whole cell or acellular pertussis components
and a second container comprising : one or more conjugates of a carrier protein and a capsular saccharide from Streptococcus pneumoniae [where the capsular saccharide is optionally from a pneumococcal serotype selected from the group consisting of 1, 2, 3, 4, 5, 6A, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F].and a third container comprising: an immunogenic composition of the invention as described above (for instance those comprising Men or HibMen saccharide conjugate combinations).

A further aspect of the invention is a process for making the immunogenic composition or vaccine of the invention, comprising the step of mixing the immunogenic composition of the invention with a pharmaceutically acceptable excipient. Also provided is an immunogenic composition of the invention for use in the treatment or prevention of disease caused by Neisseria meningitidis infection.

Also disclosed is a method of immunising a human host against disease caused by N. meningitidis and optionally Haemophilus influenzae infection comprising administering to the host an immunoprotective dose of the immunogenic composition or vaccine or kit of the invention optionally using a single dose.

Also disclosed is a method of immunising a human host with an immunogenic composition wherein a single dose administration (optionally to teenagers, adults or children) results in a blood test taken one month after administration giving over 50%, 60%, 70%, 80%, 90% or 95% responders in an SBA assay measuring levels of response against MenA, MenC, MenW and/or MenY. Optionally the SBA assay is as described in Example 9 with responder assessed as described in Example 9.

Also disclosed is an immunogenic composition comprising MenA , MenC, MenW and/or MenY conjugates which is capable of eliciting an immune response after a single dose such that over 50%, 60%, 70%, 80%, 90% or 95% of human subjects (children, teenagers or adults) inoculated are classified as responders in an SBA assay on blood extracted a month after inoculation (optionally using the criteria described in example 9).

Such an immunogenic composition optionally has the further structural characteristics described herein.

The invention is illustrated in the accompanying examples. The examples below are carried out using standard techniques, which are well known and routine to those of skill in the art, except where otherwise described in detail. The examples are illustrative , but do not limit the invention.

Examples Example 1 - preparation of polysaccharide conjugates

The covalent binding of Haemophilus influenzae (Hib) PRP polysaccharide to TT was carried out by a coupling chemistry developed by Chu et al (Infection and Immunity 1983, 40 (1); 245-256). Hib PRP polysaccharide was activated by adding CNBr and incubating at pH10.5 for 6 minutes. The pH was lowered to pH8.75 and adipic acid dihyrazide (ADH) was added and incubation continued for a further 90 minutes. The activated PRP was coupled to purified tetanus toxoid via carbodiimide condensation using 1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimide (EDAC). EDAC was added to the activated PRP to reach a final ratio of 0.6mg EDAC/mg activated PRP. The pH was adjusted to 5.0 and purified tetanus toxoid was added to reach 2mg TT/mg activated PRP. The resulting solution was left for three days with mild stirring. After filtration through a 0.45µm membrane, the conjugate was purified on a sephacryl S500HR (Pharmacia, Sweden) column equilibrated in 0.2M NaCl.

MenC -TT conjugates were produced using native polysaccharides (of over 150kDa as measured by MALLS) or were slightly microfluidised. MenA-TT conjugates were produced using either native polysaccharide or slightly microfluidised polysaccharide of over 60kDa as measured by the MALLS method of example 2. MenW and MenY-TT conjugates were produced using sized polysaccharides of around 100-200kDa as measured by MALLS (see example 2). Sizing was by microfluidisation using a homogenizer Emulsiflex C-50 apparatus. The polysaccharides were then filtered through a 0.2µm filter.

Activation and coupling were performed as described in WO96/29094 and WO 00/56360 . Briefly, the polysaccharide at a concentration of 10-20mg/ml in 2M NaCl pH 5.5-6.0 was mixed with CDAP solution (100mg/ml freshly prepared in acetonitrile/WFI, 50/50) to a final CDAP/polysaccharide ratio of 0.75/1 or 1.5/1. After 1.5 minutes, the pH was raised with sodium hydroxide to pH10.0. After three minutes tetanus toxoid was added to reach a protein/polysaccharide ratio of 1.5/1 for MenW, 1.2/1 for MenY, 1.5/1 for MenA or 1.5/1 for MenC. The reaction continued for one to two hours.

After the coupling step, glycine was added to a final ratio of glycine/PS (w/w) of 7.5/1 and the pH was adjusted to pH9.0. The mixture was left for 30 minutes. The conjugate was clarified using a 10µm Kleenpak filter and was then loaded onto a Sephacryl S400HR column using an elution buffer of 150mM NaCl, 10mM or 5mM Tris pH7.5. Clinical lots were filtered on an Opticap 4 sterilizing membrane. The resultant conjugates had an average polysaccharide:protein ratio of 1:1-1:5 (w/w).

Example 1a - preparation of MenA and MenC polysaccharide conjugates of the invention

MenC -TT conjugates were produced using native polysaccharides (of over 150kDa as measured by MALLS) or were slightly microfluidised. MenA-TT conjugates were produced using either native polysaccharide or slightly microfluidised polysaccharide of over 60kDa as measured by the MALLS method of example 2. Sizing was by microfluidisation using a homogenizer Emulsiflex C-50 apparatus. The polysaccharides were then filtered through a 0.2µm filter.

In order to conjugate MenA capsular polysaccharide to tetanus toxoid via a spacer, the following method was used. The covalent binding of the polysaccharide and the spacer (ADH) is carried out by a coupling chemistry by which the polysaccharide is activated under controlled conditions by a cyanylating agent, 1-cyano-4-dimethylamino-pyridinium tetrafluoroborate (CDAP). The spacer reacts with the cyanylated PS through its hydrazino groups, to form a stable isourea link between the spacer and the polysaccharide.

A 10mg/ml solution of MenA (pH 6.0) [3.5 g] was treated with a freshly prepared 100mg/ml solution of CDAP in acetonitrile/water (50/50 (v/v)) to obtain a CDAP/MenA ratio of 0.75 (w/w). After 1.5 minutes, the pH was raised to pH 10.0. Three minutes later, ADH was added to obtain an ADH/MenA ratio of 8.9. The pH of the solution was decreased to 8.75 and the reaction proceeded for 2 hours maintaining this pH (with temperature kept at 25 °C).

The PSAAH solution was concentrated to a quarter of its initial volume and then diafiltered with 30 volumes of 0.2M NaCl using a Filtron Omega membrane with a cut-off of 10kDa, and the retentate was filtered.

Prior to the conjugation (carbodiimide condensation) reaction, the purified TT solution and the PSAAH solution were diluted to reach a concentration of 10 mg/ml for PSAAH and 10mg/ml for TT. EDAC (1-ethyl-3-(3-dimethyl-aminopropyl) carbodiimide) was added to the PSAH solution (2g saccharide) in order to reach a final ratio of 0.9 mg EDAC/mg PSAAH. The pH was adjusted to 5.0. The purified tetanus toxoid was added with a peristaltic pump (in 60 minutes) to reach 2 mg TT/mg PSAAH. The resulting solution was left 60 min at +25°C under stirring to obtain a final coupling time of 120 min. The solution was neutralised by addition of 1M Tris-Hcl pH 7.5 (1/10 of the final volume) and left 30 minutes at +25°C then overnight at +2°C to +8°C. The conjugate was clarified using a 10µm filter and was purified using a Sephacryl S400HR column (Pharmacia, Sweden). The column was equilibrated in 10 mM Tris-HCl (pH 7.0), 0.075 M NaCl and the conjugate (approx. 660mL) was loaded on the column (+2°C to +8°C). The elution pool was selected as a function of optical density at 280 nm. Collection started when absorbance increased to 0.05. Harvest continued until the Kd reached 0.30. The conjugate was filter sterilised at +20°C, then stored at +2°C to +8°C. The resultant conjugate had a polysaccharide:protein ratio of 1:2-1:4 (w/w).

In order to conjugate MenC capsular polysaccharide to tetanus toxoid via a spacer, the following method was used. The covalent binding of the polysaccharide and the spacer (ADH) is carried out by a coupling chemistry by which the polysaccharide is activated under controlled conditions by a cyanylating agent, 1-cyano-4-dimethylamino-pyridinium tetrafluoroborate (CDAP). The spacer reacts with the cyanylated PS through its hydrazino groups, to form a stable isourea link between the spacer and the polysaccharide.

A 20mg/ml solution of MenC (pH6.0) (3.5 g) was treated with a freshly prepared 100mg/ml solution of CDAP in acetonitrile/water (50/50 (v/v)) to obtain a CDAP/MenC ratio of 1.5 (w/w). After 1.5 minutes, the pH was raised to pH 10.0. At activation pH 5M NaCl was added to achieve a final concentration of 2M NaCl. Three minutes later, ADH was added to obtain an ADH/MenC ratio of 8.9. The pH of the solution was decreased to 8.75 and the reaction proceeded for 2 hours (retained at 25 °C).

The PSCAH solution was concentrated to a minimum of 150 mL and then diafiltered with 30 volumes of 0.2M NaCl using a Filtron Omega membrane with a cut-off of 10kDa, and the retentate was filtered.

Prior to the conjugation reaction, the purified TT solution and the PSCAH solution (2g scale) were diluted in 0.2M NaCl to reach a concentration of 15 mg/ml for PSCAH and 20mg/ml for TT. The purified tetanus toxoid was added to the PSCAH solution in order to reach 2 mg TT/mg PSCAH. The pH was adjusted to 5.0. EDAC (16.7 mg/ml in Tris 0.1M pH 7.5) was added with a peristaltic pump (in 10 minutes) to reach a final ratio of 0.5 mg EDAC/mg PSCAH. The resulting solution was left 110 min at +25°C under stirring and pH regulation to obtain a final coupling time of 120 min. The solution was then neutralized by addition of 1M Tris-Hcl pH 9.0 (1/10 of final volume) and left 30 minutes at +25°C then overnight at +2°C to +8°C. The conjugate was clarified using a 10µm filter and was purified using a Sephacryl S400HR column (Pharmacia, Sweden). The column was equilibrated in 10 mM Tris-HCl (pH 7.0), 0.075 M NaCl and the conjugate (approx. 460mL) was loaded on the column (+2°C to +8°C). The elution pool was selected as a function of optical density at 280 nm. Collection started when absorbance increased to 0.05. Harvest continued until the Kd reached 0.20. The conjugate was filter sterilised at +20°C, then stored at +2°C to +8°C. The resultant conjugate had a polysaccharide:protein ratio of 1:2-1:4 (w/w).

Example 2 - determination of molecular weight using MALLS

Detectors were coupled to a HPLC size exclusion column from which the samples were eluted. On one hand, the laser light scattering detector measured the light intensities scattered at 16 angles by the macromolecular solution and on the other hand, an interferometric refractometer placed on-line allowed the determination of the quantity of sample eluted. From these intensities, the size and shape of the macromolecules in solution can be determined.

The mean molecular weight in weight (M_w) is defined as the sum of the weights of all the species multiplied by their respective molecular weight and divided by the sum of weights of all the species.

a) Weight-average molecular weight: -Mw-
b) Number-average molecular weight: -Mn-
c) Root mean square radius: -Rw- and R²w is the square radius defined by:
- (-m_i- is the mass of a scattering centre i and -r_i- is the distance between the
- scattering centre i and the center of gravity of the macromolecule).
d) The polydispersity is defined as the ratio -Mw / Mn-.

Meningococcal polysaccharides were analysed by MALLS by loading onto two HPLC columns (TSKG6000 and 5000PWxl) used in combination. 25µl of the polysaccharide were loaded onto the column and was eluted with 0.75ml of filtered water. The polysaccharides are detected using a light scattering detector (Wyatt Dawn DSP equipped with a 10mW argon laser at 488nm) and an inferometric refractometer (Wyatt Otilab DSP equipped with a P100 cell and a red filter at 498nm).

The molecular weight polydispersities and recoveries of all samples were calculated by the Debye method using a polynomial fit order of 1 in the Astra 4.72 software.

Example 3 - clinical trial comparing immunisation with Meningitec or a larger sized MenC-TT conjugate

A phase II, open, controlled study was carried out to compare GSK Biologicals meningococcal serogroup C conjugate vaccine (MenC) with GSK Biological's Haemophilus influenzae b-meningococcal serogroup C conjugate vaccine (Hib-MenC) or Meningitec ®. Each dose of Meningitec ® contains 10µg of meningococcal serogroup C oligosaccharide conjugated to 15µg of CRM197 and is produced by Wyeth. The GSK MenC conjugates contained native polysaccharides of about 200kDa conjugated to tetanus toxoid (TT).

The study consisted of five groups, each planned to contain 100 subjects, allocated to two parallel arms as follows: In this present study, all subjects in both arms received one-fifth (1/5) of a dose of Mencevax™ ACWY and a concomitant dose of Infanrix™ hexa at 12-15 months of age (Study Month 0). Two blood samples were collected from all subjects (Study Month 0 and Study Month 1). Arm 1 consisted of four groups from a primary vaccination study who were primed at their age of 3, 4 and 5 months with the following vaccines:

Group K: MenC (10 µg), non-adsorbed to aluminium salts (non-ads), tetanus toxoid (TT) conjugate and Infanrix™ hexa (MenC10-TT + Infanrix™ hexa)
Group L: Hib (10 µg)-MenC (10 µg), non-ads TT conjugate and Infanrix™ penta (Hib10-MenC10-TT + Infanrix™ penta)
Group M: Hib (5 µg)-MenC (5 µg), non-ads, TT conjugate and Infanrix™ penta (Hib5-MenC5-TT + Infanrix™ penta)
Group N: Meningitec™ and Infanrix™ hexa (Meningitec™ + Infanrix™ hexa)

The two Hib-MenC-TT vaccine groups (Groups L and M) were kept blinded in the booster study as to the exact formulation of the candidate vaccine. Arm 2-(Group O) consisted of age-matched subjects not previously vaccinated with a meningococcal serogroup C vaccine (naïve) but who had received routine pediatric vaccines according to the German Permanent Commission on Immunization.

Criteria for evaluation:

Immunogenicity. Determination of bactericidal antibody titers against meningococcal C (SBA-MenC) by a bactericidal test (cut-off: a dilution of 1:8) and ELISA measurement of antibodies against meningococcal serogroup C (assay cut-off: 0.3 µg/ml), the Hib polysaccharide PRP (assay cut-off: 0.15 µg/ml) and tetanus toxoid (assay cut-off: 0.1 IU/ml) in blood samples obtained prior to vaccination and approximately one month after vaccination in all subjects.

Statistical methods:

Demographics: Determination of mean age in months (with median, range and standard deviation [SD]), and racial and gender composition of the ATP and Total vaccinated cohorts.

Immunogenicity:

Two analyses of immunogenicity were performed based on the ATP cohort for immunogenicity (for analyses of immune memory and booster response) or the ATP cohort for safety (for analysis of persistence). These included: Evaluation of immune memory for MenC and booster response for Hib and Tetanus (before and one month after administration of 1/5 dose of the plain polysaccharide vaccine):

Determination of geometric mean titers and concentrations (GMTs and GMCs) with 95% confidence intervals (95% Cl)
Determination of the percentage of subjects with antibody titer/concentration above the proposed cutoffs with exact 95% Cl (seropositivity/seroprotection rates)
Investigation of antibody titers/concentration after vaccination using reverse cumulative curves
Computation of standardized asymptotic 95% Cl for the difference in seropositivity/seroprotection rate
between the primed group (Groups K, L, M and N) and the unprimed group (Group O)
Determination of the geometric mean of individual ratio of SBA-MenC titer over anti-PSC concentration, with 95% Cl
Determination of the 95% Cl for the post-vaccination GMT/C ratio between the groups K, L, M and the control group N for anti-PRP and anti-tetanus and between each primed group (Groups K, L, M and N) and the unprimed group (Group O) for SBA-MenC and anti-PSC using an ANOVA model

Results

Antibody	Group	N	GMT/C	95% CL LL	95% CL UL
SBA-MenC	K -MenC-TT	71	3508.9	2580.1	4772.2
L -HibMenC	79	2530.1	1831.7	3494.7
M-HibMenC	81	5385.4	4425.0	6554.2
N -Meningitec	85	1552.6	1044.4	2307.9
O - Control	91	9.3	6.3	13.6
Anti-PSC	K -MenC-TT	70	28.10	22.59	34.95
L - HibMenC	71	30.01	24.09	37.38
M-HibMenC	76	34.58	29.10	41.09
N -Meningitec	78	16.59	12.98	21.21
O - Control	94	3.05	2.36	3.93

Group K: subjects primed with MenC10-TT + Infanrix. hexa; Group L: subjects primed with Hib10-MenC10-TT + Infanrix. penta; Group M: subjects primed with Hib5-MenC5-TT + Infanrix. penta; Group N: subjects primed with Meningitec. + Infanrix. hexa; Group O: control subjects (i.e. subjects not primed with MenC conjugate vaccine) N: number of subjects with available results

Higher titres of antibodies against MenC and higher SBA titres were achieved by priming with the larger sized MenC polysaccharide conjugate vaccines (groups K, L and M) compared with the Meningitec oligosaccharide conjugate vaccine.

Group	Timing	N	GMR	LL	UL
K	Pre	70	49.470	34.939	70.044
Post	66	126.138	101.419	156.882
L	Pre	76	36.528	25.849	51.621
Post	70	90.200	70.153	115.975
M	Pre	77	51.298	36.478	72.139
Post	74	164.950	139.304	195.318
N	Pre	84	22.571	16.521	30.837
Post	76	90.168	67.757	119.991
O	Pre	3	91.634	0.651	12889.8
Post	87	2.708	1.767	4.149

In all four primed groups (Groups K, L, M and N), the GMR increased significantly from pre to post booster vaccination indicating the presence of antibody maturation and functionality. GMR in the Group M (primed with Hib5-MenC5-TT) was higher than in the Group N (primed with Meningitec™).

Endpoints	Group	N	%	Group	N	%	Difference	Value%
SBAMenC ≥ 1:8	K	79	88.6	N	91	80.2	N-K	-8.4
	L	84	93.3	N	91	80.2	N-L	-3.1
	M	85	87.1	N	91	80.2	N-M	-6.8
SBAMenC ≥ 1:128	K	79	65.8	N	91	51.6	N-K	-14.2
	L	84	56.0	N	91	51.6	N-L	-4.3
	M	85	64.7	N	91	51.6	N-M	-13.1
Anti-PSC ≥0.3µg/ml	K	79	100.0	N	91	100.0	N-K	0.0
	L	84	100.0	N	91	100.0	N-L	0.0
	M	88	98.9	N	91	100.0	N-M	1.1
Anti-PSC ≥2µg/ml	K	79	72.2	N	91	81.3	N-K	9.2
	L	84	64.3	N	91	81.3	N-L	17.0
	M	88	64.3	N	91	81.3	N-M	8.6
Anti-PRP ≥0.15µg/ml	K	81	88.9	N	91	85.7	N-K	-3.2
	L	86	96.5	N	91	85.7	N-L	-10.8
	M	90	98.9	N	91	85.7	N-M	-13.2
Anti-PRP ≥1 µg/ml	K	81	33.3	N	91	28.6	N-K	-4.8
	L	86	55.8	N	91	28.6	N-L	-27.2
	M	90	74.4	N	91	28.6	N-M	-45.9
Anti-tetanus ≥0.1 IU/ml	K	81	100.0	N	91	96.7	N-K	-3.3
	L	86	100.0	N	91	96.7	N-L	-3.3
	M	90	100.0	N	91	96.7	N-M	-3.3

Group K: subjects primed with MenC10-TT + Infanrix™ hexa; Group L: subjects primed with Hib10-MenC10-TT + Infanrix™ penta; Group M: subjects primed with Hib5-MenC5-TT + Infanrix™ penta; Group N: subjects primed with Meningitec™ + Infanrix™ hexa; N: number of subjects with available results

Higher SBA titres against MenC were achieved by priming with the larger size of MenC (groups K, L and M) compared to priming with the MenC-oligosaccharide conjugate Meningitec.

Immune memory (ATP cohort for immunogenicity)

Administration of 1/5 dose of the plain polysaccharide ACWY vaccine elicited very high SBA-MenC titer in all four primed groups with 98.7-100% and 97.5-100% of subjects primed with a candidate vaccine regimen exhibiting titers ≥1:8 and ≥1:128, respectively. In the group primed with the Meningitec™ regimen, there was a trend for a lower percentage of subjects with titers ≥1:128 (91.8%). In comparison, 17.6% of unprimed subjects had SBA MenC titers ≥ 1:8 and ≥1:128.

Example 4 Phase II clinical trial on HibMenAC -TT conjugate vaccine mixed with DTPw-HepB

Study design: Open, randomized (1:1:1:1:1), single centre study with five groups. The five groups received the following vaccination regimen respectively, at 6, 10 and 14 weeks of age.

Tritanrix™-HepB/Hib-MenAC 2.5/2.5/2.5: henceforth referred to as 2.5/2.5/2.5
Tritanrix™-HepB/Hib-MenAC 2.5/5/5: henceforth referred to as 2.5/5/5
Tritanrix™-HepB/Hib-MenAC 5/5/5: henceforth referred to as 5/5/5
Tritanrix™-HepB + Hiberix™: henceforth referred to as Hiberix
Tritanrix.-HepB/Hiberix™ + Meningitec™: henceforth referred to as Meningitec Blood samples were taken at the time of the first vaccine dose (Pre) and one month after the third vaccine dose (Post-dose 3).

Tritanrix is a DTPw vaccine marketed by GlaxoSmithKline Biologicals S.A.

105 subjects were used in each of the five groups giving a total of 525 subjects in the study.

Components per dose (0.5ml)	2.5/2.5/2.5*	2.5/5/5	5/5/5
Hib capsular polysaccharide PRP conjugated to tetanus toxoid (TT)	2.5µg	2.5µg	5µg
2.5µg	5µg	5µg
2.5µg	5µg	5µg

* The 2.5/2.5/2.5 vaccine was a dose dilution of GSK Biologicals' Hib-MenAC 5/5/5 vaccine containing 25µg of each of PRP-TT, MenA-TT and MenC-TT.

The Hib-MenAC vaccine formulations were mixed extemporaneously with Tritanirix-HepB. GSK Biologicals' combined diphtheria-tetanus-whole cell Bordetella pertussis - hepatitis B (DTPw-HB) vaccine (Tritanrix-HepB) contains not less than 30 International Units (IU) of diphtheria toxoid, not less than 60 IU of tetanus toxoid, not less than 4IU of killed Bordetella pertussis and 10µg of recombinant hepatitis B surface antigen.

Reference therapy, dose, mode of administration, lot No.:

Vaccination schedule/site: One group received Tritanrix™-HepB vaccine intramuscularly in the left thigh and Hiberix™ intramuscularly in the right thigh at 6, 10 and 14 weeks of age. Another group received Tritanrix™-HepB/Hiberix™ vaccine intramuscularly in the left thigh and Meningitec. vaccine intramuscularly in the right thigh at 6, 10 and 14 weeks of age.

Vaccine/composition/dose/lot number: The Tritanrix™-HepB vaccine used was as described above.

One dose (0.5 ml) of GSK Biologicals' Haemophilus influenzae type b conjugate vaccine: Hiberix™ contained 10 µg of PRP conjugated to tetanus toxoid. In the Hiberix™ Group, it was mixed with sterile diluent and in the Meningitec™ Group it was mixed with Tritanrix™-HepB.

One dose (0.5 ml) of Wyeth Lederle's MENINGITEC™ vaccine contained: 10 µg of capsular oligosaccharide of meningococcal group C conjugated to 15 µg of Corynebacterium diphtheria CRM197 protein and aluminium as salts.

Results - immune responses generated against Hib, MenA and MenC

Group	2.5/2.5/2.5			2.5/5/5			5/5/5			Hiberix™			Meningitec™
	%	95%CL		%	95%CL		%	95%CL		%	95%CL		%	95%CL
	GMC/T	LL	UL	GMC/ T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL
%≥0.15	100	96.5	100	99.0	94.8	100	100	96.5	100	100	96.5	100	100	96.5	100
GMC	20.80	15.96	27.10	22.62	17.72	28.88	19.36	15.33	24.46	38.55	29.93	49.64	10.94	8.62	13.88

Group	2.5/2.5/2.5			2.5/5/5			5/5/5			Hiberix™			Meningitec™
	%	95%CL		%	95%CL		%	95%CL		%	95%CL		%	95%CL
	GMC/ T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL
%≥1:8	99	94.7	100	100	96.5	100	100	96.5	100	2.9	0.6	8.4	100	96.5	100
GMT	3132	2497	3930	4206	3409	5189	3697	3118	4384	4.7	3.9	5.6	4501	3904	5180

Group	2.5/2.5/2.5			2.5/5/5			5/5/5			Hiberix™			Meningitec™
	%	95%CL		%	95%CL		%	95%CL		%	95%CL		%	95%CL
	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL
%≥1:8	99.7	91.9	99.7	100	95.8	100	100	96.2	100	6.8	2.5	14.3	9.1	4.0	17.1
GMT	316.7	251.4	398.9	418.5	358.6	488.5	363	310.5	424.4	5.6	4.3	7.4	5.6	4.4	7.2

Group	2.5/2.5/2.5			2.5/5/5			5/5/5			Hiberix™			Meningitec™
	%	95%CL		%	95%CL		%	95%CL		%	95%CL		%	95%CL
	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL
%≥0.3	100	96.5	100	100	96.4	100	100	96.5	100	8.2	3.6	15.6	100	96.5	100
GMC	49.03	43.24	55.59	71.11	62.49	80.92	61.62	54.88	69.20	0.17	0.15	0.19	58.02	51.42	65.46

Group	2.5/2.5/2.5			2.5/5/5			5/5/5			Hiberix™			Meningitec™
	%	95%CL		%	95%CL		%	95%CL		%	95%CL		%	95%CL
	GMC/T	LL	UL	GMC/	T LL	UL	GMC/T	LL	UL	GMC/T	LL	UL	GMC/T	LL	UL
%≥0.3	100	96.4	100	100	96.5	100	99.0	94.8	100	1.0	0.0	5.4	5.9	2.2	12.5
GMC	18.10	15.34	21.35	26.51	22.93	30.79	23.40	20.05	27.30	0.15	0.15	0.15	0.17	0.15	0.18

Conclusion

A comparison of the immunogenicity results achieved using the oligosaccharide MenC-CRM197 conjugate vaccine and the three GSK formulations which contain polysaccharide MenA-TT and MenC -TT conjugates showed that the polysaccharide Men conjugates were able to elicit a good immunogenic response similar to that achieved using the oligosaccharide conjugate vaccine Meningitec. All formulations tested gave a response to MenC in 100% of patients.

Example 5 - Phase II clinical trial administering Hib MenCY concomitantly with Infanrix™ penta according to a 2, 3 and 4 month schedule

Study design: A Phase II, open (partially double-blind*) randomized controlled multi-center study with 5 groups receiving a three-dose primary schedule with vaccines as follows:

Group Hib-MenCY 2.5/5/5: Hib-MenCY (2.5/5/5) + Infanrix™ penta
Group Hib-MenCY 5/10/10: Hib-MenCY (5/10/10) + Infanrix™ penta
Group Hib-MenCY 5/5/5: Hib-MenCY (5/5/5) + Infanrix™ penta
Group Hib-MenC: Hib-MenC (5/5) + Infanrix™ penta
Group Menjugate: Menjugate™** + Infanrix™ hexa (control). *Hib-MenCY 2.5/5/5, Hib-MenCY 5/10/10 and Hib-MenC were administered in a double-blind manner while the Hib-MenCY 5/5/5 group and the Menjugate™ group were open. The 2.5/5/5, 5/10/10 and 5/5/5 formulations of Hib-MenCY contain MenC native polysaccharides and MenY polysaccharides which are microfluidized.**Menjugate™ contains 10µg of MenC oligosaccharides conjugated to 12.5-25µg of CRM197 per dose and is produced by Chiron.

Vaccination at +/- 2, 3, 4 months of age (Study Month 0, Month 1 and Month 2), and blood samples (3.5ml) from all subjects prior to and one month post primary vaccination (Study Month 0 and Month 3).

Study vaccine, dose, mode of administration, lot number: Three doses injected intramuscularly at one month intervals, at approximately 2, 3 and 4 months of age as follows:

Table 6: Vaccines administered (study and control), group, schedule/site and dose


Hib-MenCY 2.5/5/5	2, 3, and 4	Hib (2.5µg)- MenC-TT (5µg)-MenY-TT (5 µg)	DTPa-HBV-IPV (Infanrix™ penta)
Hib-MenCY 5/10/10	2, 3, and 4	Hib (5µg)-MenC-TT (1µg)-MenY-TT (10µg)	DTPa-HBV-IPV (Infanrix™ penta)
Hib-MenCY 5/5/5	2, 3, and 4	Hib (5µg)-MenC-TT ( 5µg))-MenY-TT (5µg)	DTPa-HBV-IPV (Infanrix™ penta)
Hib-MenC	2, 3, and 4	Hib (5µg)-Men C (5µg)	DTPa-HBV-IPV (Infanrix™ penta)
Menjugate™	2, 3, and 4	Menjugate™	DTPa-HBV-IPV/Hib (Infanrix™hexa)

Immunogenicity: Measurement of antibody titres/concentrations against each vaccine antigen: Prior to the first dose (Month 0) and approximately one month after the third dose (Month 3) in all subjects for: SBA-MenC and SBA-MenY, anti-PSC and anti-PSY, anti-PRP, anti-T, anti-FHA, anti-PRN and anti-PT. Using serum bactericidal activity against N. meningitidis serogroups C and Y (SBA-MenC and SBA-MenY cut-off: 1:8 and 1:128); ELISA assays with cut-offs: ≥0.3 µg/ml and ≥2µg/ml for anti- N. meningitidis serogroups C and Y polysaccharides (anti-PSC IgG and anti-PSY IgG); ≥0.15 µg/ml and ≥1.0µg/ml for Hib polysaccharide polyribosil-ribitol-phosphate (anti-PRP IgG); 5EL.U/ml for anti-FHA, anti-PRN, anti-PT; ≥0.1 IU/ml anti-tetanus toxoid (anti-TT). Only at one month after the third dose (Month 3) in all subjects for: anti-D, anti-HBs and anti-polio 1, 2 and 3. Using ELISA assays with cut-offs: 0.1 IU/ml for anti-diphtheria (anti-D); ≥10 mIU/ml for antihepatitis B (anti-HBs); and microneutralization test cut-off: 1:8 for anti-polio type 1, 2 and 3 (anti-polio 1, 2 and 3).

Statistical methods:

The seroprotection/seropositivity rates and geometric mean concentrations/titres (GMCs/GMTs) with 95% confidence intervals (95% Cl) were computed per group, for SBA-MenC, anti-PSC, SBA-MenY, anti-PSY, anti-PRP, anti-Tetanus, anti-PT, anti-FHA and anti-PRN prior to and one month after vaccination; for anti-Diphtheria, anti-HBs, anti-Polio 1, anti-Polio 2 and anti-Polio 3 one month after vaccination. Vaccine response (appearance of antibodies in subjects initially seronegative or at least maintenance of antibody concentrations in subjects initially seropositive) with 95% Cl for anti-PT, anti-PRN and anti-FHA were also computed one month after vaccination. Reverse cumulative curves for each antibody at Month 3 are also presented. The differences between the Hib-MenCY and the Hib- MenC groups, compared with the Menjugate™ control group were evaluated in an exploratory manner for each antibody, except for SBA-MenY and anti-PSY, in terms of (1) the difference between the Menjugate™ group (minus) the Hib-MenCY and Hib-MenC groups for the percentage of subjects above the specified cut-offs or with a vaccine response with their standardized asymptotic 95% Cl, (2) the GMC or GMT ratios of the Menjugate™ group over the Hib-MenCY and Hib-MenC groups with their 95% Cl. The same comparisons were done to evaluate the difference between each pair of Hib-MenCY formulations for anti-PRP, SBA-MenC, anti-PSC, SBA-MenY, anti-PSY and anti-TT antibodies.

The overall incidences of local and general solicited symptoms were computed by group according to the type of symptom, their intensity and relationship to vaccination (as percentages of subjects reporting general, local, and any solicited symptoms within the 8 days following vaccination and their exact 95% CI). Incidences of unsolicited symptoms were computed per group. For Grade 3 symptoms, onset ≤48 hours, medical attention, duration, relationship to vaccination and outcomes were provided. Serious Adverse Events were fully described.

Seroprotection/seropositivity rates &GMC/Ts (ATP cohort for immunogenicity)


Hib MenCY 2.5/5/5	67	100.0	94.6	100.0	98.5	92.0	100.0	9.01	7.25	11.21
Hib MenCY 5/10/10	67	100.0	94.6	100.0	98.5	92.0	100.0	9.49	7.72	11.65
Hib MenCY 5/5/5	70	100.0	94.9	100.0	98.6	92.3	100.0	8.08	6.53	9.98
Hib MenC	74	100.0	95.1	100.0	98.6	92.7	100.0	10.44	8.49	12.83
Menjugate™	71	100.0	94.9	100.0	80.3	69.1	88.8	2.60	1.97	3.43


Hib MenCY 2.5/5/5	70	100.0	94.9	100.0	95.7	88.0	99.1	1005.8	773.5	1308.0
Hib MenCY 5/10/10	67	100.0	94.6	100.0	94.0	85.4	98.3	1029.8	799.7	1326.0
Hib MenCY 5/5/5	71	100.0	94.9	100.0	94.4	86.2	98.4	906.9	691.3	1189.8
Hib MenC	74	100.0	95.1	100.0	95.9	88.6	99.2	871.0	677.3	1120.0
Menjugate™	71	100.0	94.9	100.0	100.0	94.9	100.0	3557.6	2978.8	4248.8


Hib MenCY 2.5/5/5	69	100.0	94.8	100.0	100.0	94.8	100.0	21.70	18.36	25.65
Hib MenCY 5/10/10	66	100.0	94.6	100.0	100.0	94.6	100.0	27.26	23.26	31.95
Hib MenCY 5/5/5	70	100.0	94.9	100.0	100.0	94.9	100.0	19.02	16.49	21.93
Hib MenC	74	100.0	95.1	100.0	100.0	95.1	100.0	21.08	18.24	24.35
Menjugate™	71	100.0	94.9	100.0	100.0	94.9	100.0	38.49	33.64	44.05


Hib MenCY 2.5/5/5	69	97.1	89.9	99.6	92.8	83.9	97.6	470.7	351.1	631.2
Hib MenCY 5/10/10	66	97.0	89.5	99.6	86.4	75.7	93.6	437.1	322.0	593.4.8
Hib MenCY 5/5/5	71	98.6	92.4	100.0	95.8	88.1	99.1	635.3	501.5	804.8
Hib MenC	74	21.6	12.9	32.7	13.5	6.7	23.5	9.3	6.3	13.7
Menjugate™	71	19.7	11.2	30.9	9.9	4.1	19.3	7.5	5.4	10.4


Hib MenCY 2.5/5/5	69	100.0	94.8	100.0	100.0	94.8	100.0	26.86	22.86	31.56
Hib MenCY 5/10/10	66	100.0	94.6	100.0	100.0	94.6	100.0	37.02	31.84	43.04
Hib MenCY 5/5/5	70	100.0	94.9	100.0	100.0	94.9	100.0	23.57	19.94	27.86
Hib MenC	74	8.1	3.0	16.8	4.1	0.8	11.4	0.19	0.15	0.25
Menjugate ™	71	5.6	1.6	13.8	1.4	0.0	7.6	0.17	0.15	0.19


Hib MenCY 2.5/5/5	68	100.0	94.7	100.0	3.06	2.63	3.55
Hib MenCY 5/10/10	67	100.0	94.6	100.0	3.25	2.88	3.68
Hib MenCY 5/5/5	70	100.0	94.9	100.0	2.97	2.59	3.41
Hib MenC	74	100.0	95.1	100.0	3.15	2.73	3.64
Menjugate™	71	100.0	94.9	100.0	1.66	1.39	1.97

Conclusion

The MenC and Y polysaccharide conjugates produced a good immune response in all subjects with 100% of subjects producing above 0.3 µg/ml responses against MenC and MenY.

Example 6 - Phase II clinical trial comparing three formulations of MenACWY-TT with Meningitec MenC-CRM197 oligosaccharide-conjugate vaccine.

This example reports a phase II, open (partially-blind), randomized, controlled dose-range study to evaluate the Immunogenicity of three different formulations of GlaxoSmithKline Biological's meningococcal serogroups A, C, W-135, Y tetanus toxoid conjugate (MenACWY-TT) vaccine in comparison to a MenC oligosaccharide-CRM197 conjugate vaccine (Meningitec™) when given as one dose to children aged 12-14 months.

The clinical trial was an open (partially double-blind*), controlled, multicentric study in which eligible subjects of 12-14 months were randomized (1:1:1:1) to one of four parallel groups of 50 subjects to receive a single primary dose at Visit 1 as follows:

Form 1T: MenACWY-TT at a dose of 2.5µg of MenA polysaccharide conjugated to tetanus toxoid (TT), 2.5µg of MenC polysaccharide conjugated to TT, 2.5µg of MenW polysaccharide conjugated to TT and 2.5µg of MenY polysaccharide conjugated to TT.
Form 2T: MenACWY-TT at a dose of 5µg of MenA polysaccharide conjugated to TT, 5µg of MenC polysaccharide conjugated to TT, 5µg of MenW polysaccharide conjugated to TT and 5µg of MenY polysaccharide conjugated to TT.
Form 3T: MenACWY-TT at a dose of 2.5µg of MenA polysaccharide conjugated to TT, 10µg of MenC polysaccharide conjugated to TT, 2.5µg of MenW polysaccharide conjugated to TT and 2.5µg of MenY polysaccharide conjugated to TT.
Ctrl T: 10µg MenC oligosaccharide conjugated to 12.5-25µg CRM197 (Meningitec).
*The three different MenACWY-TT formulations were administered in a double-blind manner.

Vaccination schedule/site: A single vaccine dose was administered intramuscularly in the left deltoid at Visit 1 (Study Month 0) according to randomized assignment. All candidate vaccines were supplied as a lyophilized pellet in a monodose vial (0.5 ml after reconstitution with the supplied saline diluent).

Immunogenicity. Measurement of titers/concentrations of antibodies against meningococcal vaccine antigen components in blood samples obtained prior to the study vaccine dose (Month 0) and approximately one month after the study vaccine dose (Month 1) in all subjects. Determination of bactericidal antibody titers against N. meningitidis serogroups A, C, W-135 and Y (SBA-MenA, SBA-MenC, SBA-MenW and SBA-MenY) by a bactericidal test (assay cut-offs: a dilution of 1:8 and 1:128) and ELISA measurement of antibodies against N. meningitidis serogroups A, C, W-135 and Y (anti-PSA, anti-PSC, anti-PSW and anti-PSY, assay cut-offs ≥0.3µg/ml and ≥2µg/ml), and tetanus toxoid (anti-tetanus, assay cut-off 0.1 IU/ml).

Results

Antibody response in terms of the percentage of SBA-MenA, SBA-MenC, SBA-MenW and SBA-MenY responders one month after vaccination (the primary endpoint) is shown in Table 8. A response is defined as greater than or equal to a 4-fold increase for seropositive subjects or seroconversion for seronegative subjects before vaccination.

Antibody	Group	N	%	LL	UL
4 SBA-MenA	Form 1T	42	61.9	45.6	76.4
	Form 2T	39	82.1	66.5	92.5
	Form 3T	40	62.5	45.8	77.3
	Meningitec™	36	11.1	3.1	26.1
SBA-MenC	Form 1T	46	97.8	88.5	99.9
	Form 2T	43	100.0	91.8	100.0
	Form 3T	44	95.5	84.5	99.4
	Meningitec™	49	91.8	80.4	97.7
SBA-MenW	Form 1T	45	100.0	92.1	100.0
	Form 2T	43	97.7	87.7	99.9
	Form 3T	45	100.0	92.1	100.0
	Meninqitec™	46	15.2	6.3	28.9
SBA-MenY	Form 1T	47	97.9	88.7	99.9
	Form 2T	44	88.6	75.4	96.2
	Form 3T	45	93.3	81.7	98.6
	Meningitec™	49	4.1	0.5	14.0

Table 9 shows the numbers of subjects achieving SBA titres over cutoff points of 1:8 and 1:128 as well as GMTs.

	Group	N		≥1:8 LL			≥1:128 LL
			%		UL	%		UL	GMT
SBA-MenA	Form 1T	46	100	92.3	100	100	92.3	100	1457.3
	Form2T	45	100	92.1	100	97.8	88.2	99.9	1776.9
	Form3T	48	97.9	88.9	99.9	97.9	88.9	99.9	1339.5
	Meningitec™	41	51.2	35.1	67.1	43.9	28.5	60.3	42.8
SBA-MenC	Form 1T	47	97.9	88.7	99.9	78.7	64.3	89.3	281.3
	Form2T	45	100	92.1	100	84.4	70.5	93.5	428.6
	Form3T	47	95.7	85.5	99.5	85.1	71.7	93.8	478.4
	Meningitec™	50	94.0	83.5	98.7	62.0	47.2	75.3	200.1
SBA-Men W	Form 1T	47	100	92.5	100	100	92.5	100	2529.1
	Form2T	45	100	92.1	100	100	92.1	100	2501.6
	Form3T	48	100	92.6	100	97.9	88.9	99.9	2300.2
	Meningitec™	48	27.1	15.3	41.8	6.3	1.3	17.2	9.4
SBA-MenY	Form 1T	47	100	92.5	100	100	92.5	100	1987.4
	Form2T	45	100	92.1	100	100	92.1	100	2464.8
	Form3T	48	100	92.6	100	97.9	88.9	99.9	2033.7
	Meningitec™	49	49.0	34.4	63.7	28.6	16.6	43.3	25.0

Vaccination with all three formulations of the ACWY-TT polysaccharide conjugate led to good SBA responses against MenA, MenC, MenW and MenY with 95-100% of subjects with titres greater than 1:8. In particular, the 5/5/5/5 and 2.5/10/2.5/2.5 formulations of the polysaccharide conjugates produced a higher response against MenC than the oligosaccharide Meningitec™ vaccine as seen by a higher proportion of subjects having a titre greater than 1:128 and the GMT readings.

	Group	N		≥0.3µg /ml			≥2µg/ ml		GMC
			%	LL	UL	%	LL	UL	µg/ml
Anti-MenA	Form 1T	47	93.6	82.5	98.7	68.1	52.9	80.9	2.35
	Form2T	45	100	92.1	100	64.4	48.8	78.1	3.11
	Form3T	48	95.8	85.7	99.5	37.5	24.0	52.6	1.65
	Meningitec™	50	10.0	3.3	21.8	2.0	0.1	10.6	0.18
Anti-MenC	Form 1T	47	100	92.5	100	100	92.5	100	9.57
	Form2T	45	100	92.1	100	100	92.1	100	12.53
	Form3T	47	100	92.5	100	97.9	88.7	99.9	19.29
	Meningitec™	49	98.0	89.1	99.9	93.9	83.1	98.7	7.95
Anti-Men W	Form 1T	47	100	92.5	100	80.9	66.7	90.9	4.56
	Form2T	45	100	92.1	100	93.3	81.7	98.6	6.83
	Form3T	48	93.8	82.8	98.7	72.9	58.2	84.7	2.88
	Meningitec™	50	0.0	0.0	7.1	0.0	0.0	7.1	0.15
Anti-MenY	Form 1T	47	100	92.5	100	97.9	88.7	99.9	8.90
	Form2T	45	100	92.1	100	100	92.1	100	12.78
	Form3T	47	97.9	88.7	99.9	87.2	74.3	95.2	5.67
	Meningitec™	50	2.0	0.1	10.6	0.0	0.0	7.1	0.15

All three formulations of the ACWY-TT polysaccharide conjugate vaccine produced good immune responses against MenA, MenC, MenW and MenY with between 93% and 100% of subjects achieving titres grater than 0.3µg/ml. Higher GMC readings were achieved using the 5/5/5/5 and 2/5/10/2.5/2.5 formulations of the ACWY-TT polysaccharide conjugate vaccine in comparison with Meningitec.

Example 7 - comparison of immunogenicity of native and sized MenY polysaccharide conjugates

Mice (female DBA/2 of 6-8 wk) received two injections, 2 weeks apart, of PSY-TT by the subcutaneous route. Blood samples were taken 14 days after the second injection in order to perform anti-PSY ELISA and SBA using S1975 menY strain. Per injection, mice received 1 µg of PSY-TT(lyo non-ads formulation).

The conjugates described in table 11 were used .

Table 11

Conjugates	ENYTT012	ENYTT014	ENYTT015 bis
PSY microfluidisation	NO	Yes (40 cycles)	Yes (20 cycles)
TT/PS ratio	1/1	1/1	1/1

Results

The results (Figure 1) show a trend towards higher immunogenicity for conjugates prepared using sized PSY. Figure 1A shows the GMC results obtained in an ELISA for antisera raised against conjugates prepared from native MenY (ENYTT012), microfluidised MenY - 40 cycles (ENYTT014) and microfluidised MenY - 20 cycles (ENYTT015 bis). Higher GMCs were obtained where the MenY-TT was prepared from microfluidised MenY.

Similar results were obtained when the antisera were assessed by SBA assay (Figure 1B). Again the higher GMT values were achieved using conjugates prepared from microfluidised MenY.

Example 8 - Clinical trial assessing the effect of a linker in MenA in a MenACWY conjugate vaccine

A single dose of different formulations of MenACWY vaccine was administered to teenagers of 15-19 years in 5 groups of 25 subjects in a 1:1:1:1:1 randomised trial. The formulations tested were:

F1 - MenACWY conjugated to tetanus toxoid with the MenA conjugate containing an AH spacer - 5/5/5/5µg
F2 - MenACWY conjugated to tetanus toxoid with the MenA conjugate containing an AH spacer - 2.5/5/2.5/2.5µg
F3 - MenACWY conjugated to tetanus toxoid with the MenA conjugate containing an AH spacer - 5/5/2.5/2.5µg
F4 - MenACWY conjugated to tetanus toxoid with no spacer in any conjugate - 5/5/5/5µg Control group - Mencevax ACWY

On day 30 after inoculation, a blood sample was taken from the patients.

The blood samples were used to assess the percentage of SBA-MenA, SBA-MenC, SBA-MenW135 and SBA-MenY responders one month after the vaccine dose. A vaccine response was defined as 1) for initially seronegative subjects - a post-vaccination antibody titre ≥ 1/32 at 1 month or 2) for initially seropositive subjects - antibody titre of ≥ 4 fold the pre-vaccination antibody titre.

Results

As shown in Table 13, the use of a spacer in the MenA conjugate led to an increased immune response against MenA. The percentage of responders rose from 66% to 90-95% when the AH spacer was added. This was reflected in an increase in SBA GMT from 4335 to 10000 and an increase in GMC from 5 to 20-40. Surprisingly, the use of a AH spacer also led to an increased immune response against MenC as seen by an increase in the percentage of responders and an increase in the SBA GMT. An increase could also be seen in the SBA-GMT against MenY (6742-7122) and against MenW (4621-5418) when a spacer was introduced.

Formulation	% SBA MenA responders	SBA-MenA GMT	Anti-PSA GMC µg/ml ELISA
90.9	9805	20.38
75	8517	29.5
95.5	10290	47.83
66.7	4335	5.46
Mencevax™	85.7	8022	27.39

Formulation	% SBA MenC responders	SBA-MenC GMT	Anti-PSC GMC µg/ml ELISA
69.6	3989	12.11
81.8	3524	12.78
81.8	3608	8.4
73.9	2391	8.84
Mencevax™	90.0	5447	38.71

Formulation	% SBA MenW responders	SBA-MenW GMT	Anti-PSW GMC µg/ml ELISA
95	5418	9.65
85	4469	14.55
95.5	4257	6.39
95.5	4621	10.7
Mencevax™	86.4	2714	13.57

Formulation	% SBY MenY responders	SBA-MenY GMT	Anti-PSY GMC µg/ml ELISA
91.3	7122	16.3
87.5	5755	12.52
80	5928	8.88
91.3	6742	13.88
Mencevax™	91.7	4854	21.02

Example 9 - Clinical trial assessing the effect of a linker in MenA and MenC conjugates in a MenACWY conjugate vaccine

F1 - MenACWY conjugated to tetanus toxoid with the MenA and MenC conjugates containing an AH spacer - 2.5/2.5/2.5/2.5µg
F2 - MenACWY conjugated to tetanus toxoid with the MenA and MenC conjugates containing an AH spacer - 5/5/2.5/2.5µg
F3 - MenACWY conjugated to tetanus toxoid with the MenA and MenC conjugates containing an AH spacer - 5/5/5/5µg
F4 - MenACWY conjugated to tetanus toxoid with the MenA conjugate containing an AH spacer- 5/5/5/5µg

Control group - Mencevax ACWY

On day 30 after inoculation, a blood sample was taken from the patients.

Results

The introduction of an AH spacer into the MenC conjugate led to an increase in the immune response against MenC as shown in Table 14. This is demonstrated by an increase in SBA GMT from 1943 to 4329 and an increase in anti-PSC GMC from 7.65 to 13.13. Good immune responses against MenA, MenW and MenY were maintained.

Formulation	% SBA MenA responders	SBA-MenA GMT	Anti-PSA GMC µg/ml ELISA
75	8417	20.23
72	6299	16.07
87	9264	27.26
77.3	9632	20.39
Mencevax™	78.3	8284	12.93

Formulation	% SBA MenC responders	SBA-MenC GMT	Anti-PSC GMC µg/ml ELISA
88	3619	12.82
88	2833	13.32
95.8	4329	13.13
95.8	1943	7.65
Mencevax™	91.7	1567	16.55

Formulation	% SBA MenW responders	SBA-MenW GMT	Anti-PSW GMC µg/ml ELISA
100	5656	7
96	4679	5.4
91.3	4422	4.45
88	4947	7.67
Mencevax™	96	3486	11.93

Formulation	% SBY MenY responders	SBA-MenY GMT	Anti-PSY GMC µg/ml ELISA
75	3891	17.81
92	3968	11.96
79.2	2756	9.51
80	3914	16.76
Mencevax™	88	3056	21.41

Claims

An immunogenic composition comprising N. meningitidis serogroup A capsular saccharide (MenA), N. meningitidis serogroup C capsular saccharide (MenC), N. meningitidis serogroup Y capsular saccharide (MenY) and N. meningitidis serogroup W capsular saccharide (MenW) conjugated separately to the same type of carrier protein, wherein:
(a) MenA or MenA and MenC are conjugated to the carrier protein via a carboxyl group on the protein carrier and an adipic acid dihydrazide (ADH) linker, wherein the or each capsular saccharide(s) conjugated via the ADH linker is/are conjugated to the linker with 1-cyano-4-dimethylamino pyridinium tetrafluoroborate (CDAP) chemistry and the carrier protein is conjugated to the ADH linker with 1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimide (EDAC) chemistry, wherein the saccharide:protein ratio (w/w) is between 1:2-1:5;

(b) the N. meningitidis saccharides from MenC, MenY and MenW distinct from (a), are conjugated to the carrier protein via an amino group on the protein carrier, wherein the saccharide:protein ratio (w/w) is between 5:1-1:1.99; and

(c) the carrier protein is TT.
An immunogenic composition of claim 1, wherein the first and second type of chemical group on the protein carrier are present on separate B- and/or T-cell epitopes on the carrier protein.
The immunogenic composition of claim 1 or 2, wherein the ratio of Men W saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1:1-1:1.7, 1:1.2-1:1.6, or 1:1.4-1:1.5 (w/w).
The immunogenic composition of any one of claims 1-3, wherein the ratio of Men Y saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.9, 1:1-1:1.8, 1:1.1-1:1.6, or 1:1.3-1:1.4 (w/w).
The immunogenic composition of any one of claims 1-4, wherein the ratio of Men A saccharide to carrier protein is between 1:2-1:5, 1:2.4-1:4, 1:2.7-1:3.5, or 1:2.9-1:3.1 (w/w).
The immunogenic composition of any one of claims 1-5, wherein the ratio of Men C saccharide to carrier protein is between 5:1-1:1.99, 2:1-1:1.99, 1.5:1-1:1.8, 1.3:1-1:1.6, 1.2:1-1:1.4, or 1.1:1-1:1.2 (w/w).
The immunogenic composition of any one of claims 1-5, wherein the ratio of Men C saccharide to carrier protein is between 1:2-1:5, 1:2.5-1:4.5, 1:2.7-1:4.3, 1:3-1:4, or 1:3.3-1:3.5 (w/w).
A vaccine comprising the immunogenic composition of any one of claims 1-7 and a pharmaceutically acceptable excipient.
A process for making the vaccine of claim 8 comprising the step of mixing the immunogenic composition of any one of claims 1-7 with a pharmaceutically acceptable excipient.
The immunogenic composition of any one of claims 1-7 for use in the treatment or prevention of disease caused by Neisseria meningitidis infection.