Thermoreversible oil-in-water emulsion
The invention relates to a thermoreversible oil-in-water emulsion comprising: a TLR4 agonist, the chemical structure of which does not comprise a sugar ring, squalene, a nonionic surfactant belonging to the polyoxyethylene alkyl ether chemical group, a hydrophilic surfactant, an aqueous solvent, and which shows immunostimulating properties.
1. An Oil-in-Water (O/W) emulsion comprising,
i) a TLR4 agonist, called TLR4, the chemical structure of which does not comprise a sugar ring,
ii) squalene,
iii) an aqueous solvent,
iv) a nonionic hydrophilic surfactant which is a polyoxyethylene alkyl ether, and
v) a nonionic hydrophobic surfactant,
in which the TLR4 agonist is the chemical compound ER804057, the nonionic hydrophilic surfactant is ceteareth-12, the nonionic hydrophobic surfactant is sorbitan monooleate and the aqueous solvent is a phosphate buffer or a citrate buffer, and wherein the emulsion is thermoreversible.
2. The emulsion as claimed in claim 1 , in which:
a) the amount of squalene in the emulsion is between 5% and 45% of the total weight of the emulsion,
b) the ratio of the amount of squalene to the total amount of ceteareth-12 and of sorbitan monooleate is between 2.0 and 4.0,
c) the amounts of ceteareth-12 and of sorbitan monooleate are such that the HLB is between 8.5 and 10, and
d) the ratio of the amount of ER 804057 to the total amount of ceteareth-12 and of sorbitan monooleate is between 0.01×10 −2 and 2×10 −2 .
3. The emulsion as claimed in claim 2 , further comprising mannitol in which the amount is between 0.1 and 10% of the total weight of the emulsion.