Water-soluble topical ophthalmic preparation containing lutein and production method thereof

A process for the production of a water-soluble ophthalmic topical preparation containing lutein, said process comprising, in sequence, the following operations:

• Step 1:
• a) introducing a predetermined amount of deionized water and, optionally, the components of a buffer system and, also optionally, a predetermined amount of an ophthalmic viscosifying agent into a first stirred vessel, waiting for the complete solubilization of the optional ingredients;
• Step 2:
• a) in a second stirred vessel, heating a predetermined amount of vitamin E TPGS up to a temperature of 80-90° C., and waiting for complete melting thereof;
• b) bringing the vitamin E TPGS to a temperature of 90-170° C. and adding a predetermined amount of lutein, while continuing stirring until complete dissolution and formation of a homogeneous orange oily solution, consisting exclusively of vitamin E TPGS and lutein;
• Step 3:
• a) heating the water or the aqueous solution obtained from operation a) of Step 1 to a temperature of 80-90° C. and adding an aliquot thereof equal to about 10% of the final product, gradually, to said second vessel, while keeping it under stirring;
• b) once the addition is complete, increasing the stirring speed while maintaining the temperature in the 90-170° C. range until a completely clear and optically homogeneous orange liquid is obtained;
• and
• Step 4:
• a) adding the solution of Step 3 to the remaining water or aqueous solution obtained from operation a) of Step 1;
• b) after verifying that the temperature has fallen down to. or below, 30° C., adding to the stirred vessel the other water-soluble ingredients of the topical ophthalmic preparation being produced, one at a time and in predetermined quantities, including one or more viscosifying agents and/or mucoadhesives, waiting for the complete solubilization thereof;
• c) sterilizing the product thus obtained.