Conjugates for the prevention or treatment of nicotine addiction

A hapten-spacer conjugate of the formula (II):

• wherein W is —CH2— or —O—;
• -(spacer)- is a C1-C8 alkylene group, a C3-C10 cycloalkylene group or a C1-C12 alkylene group interrupted by 1 to 4 oxygen atoms and optionally interrupted by a —N(H)C(O)—;
• and
• X is —NH2 or —SH.

A hapten-carrier conjugate of formula (III):

• wherein
• W is —CH2— or —O—;
• -(spacer)- is a C1-C8 alkylene group, a C3-C10 cycloalkylene group or a C1-C12 alkylene group interrupted by 1 to 4 oxygen atoms and optionally interrupted by a —N(H)C(O)—;
• X* is —NH— or —S—;
• m is 0 or 1;
• n is an integer from 1 to 1000;
• and
• Y is an optionally modified carrier protein selected from bacterial toxoids, immunogenic substances, viruses, virus-like particles, protein complexes, proteins, polypeptides, liposomes and immuno-stimulating complexes.

A vaccine composition comprising CpG 24555 and a plurality of hapten-carrier conjugates of the formula (IV):

• wherein
• Y is diphtheria toxoid or CRM197;
• and
• n is an integer in the range of 1 to 40 inclusive.