Process for preparing salt of hyaluronic acid with a pharmaceutically active substance
AssigneeFidia S.p.A.
InventorsFrancesco Della Valle, Aurelio Romeo, Silvana Lorenzi
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Abstract
Pharmaceutical preparations for topical administration containing a pharmacologically active substance together with hyaluronic acid or a molecular weight fraction thereof. The hyaluronic acid may be in the form of the free acid or may be a salt with an alkali or alkaline earth metal, magnesium, aluminum or ammonium, or in the form of a salt with one or more pharmacologically active substances.
Claims15
A process for the preparation of a salt of hyaluronic acid with a pharmaceutically active substance which comprises:
- (a) combining an aqueous solution of a barium salt of hyaluronic acid with a sulfate of a pharmaceutically active substance;
- and
- (b) separating the precipitated barium sulfate to obtain the salt of hyaluronic acid with a pharmaceutically active substance in aqueous solution.
A process for the preparation of a barium salt of hyaluronic acid or a molecular weight fraction thereof which comprises
- (a) treating a cetylpyridinium salt of hyaluronic acid or a molecular weight fraction thereof with an aqueous solution of barium chloride;
- and
- (b) separating the aqueous solution and adding ethanol to thereby precipitate the barium salt of hyaluronic acid or of a molecular weight fraction thereof.
Dependencies are inferred from the claim text.