Stable non-dihydrate azithromycin oral suspensions

Abstract

This invention relates to a powder for oral suspension, and an oral suspension made there from, which comprises non-dihydrate azithromycin and an azithromycin conversion stabilizing excipient, wherein said excipient reduces the conversion of the form of azithromycin, when placed in suspension, to another form of azithromycin. This invention further relates to a method for reducing the conversion of a form of non-dihydrate azithromycin, in an oral suspension, by adding a surface tension reducing excipient that reduces the surface tension of the aqueous vehicle. Furthermore, this invention relates to a method for reducing the conversion of a non-dihydrate azithromycin, in an unflavored oral suspension, by raising the viscosity of the oral suspension, and in a flavored oral suspension by lowering the viscosity of the oral suspension.

Description

Background of the invention

[0001] Azithromycin, also known as 9-deoxy-9a-aza-9a-methyl-9a-homoerythromycin A, exists as a dihydrate as well as a large number of non-dihydrate forms.

[0002] Azithromycin is administered for the treatment of a variety of infections, particularly infections of the urinary tract, bronchi, lungs, sinuses, and middle ear.

[0003] In the treatment of pediatric patients, azithromycin is administered as a dosage form of oral suspension, which is administered by single or multiple courses of treatment. The oral suspension dosage form is preferred for pediatric therapeutic use because it provides better control over the amount of azithromycin administered and because many pediatric patients are unable to swallow other oral dosage forms. However, since azithromycin has a very bitter taste, suitable flavoring is required to ensure patient compliance and reduce vomiting after swallowing. More recently, oral suspensions of azithromycin have included azi...