Northwest University

Wilna Liebenberg

Marique Aucamp

Melgardt M De Villiers

Nicole Stieger

The invention provides a method for increasing the solubility of nevirapine, including the steps of rendering nevirapine in a gaseous phase; and rendering the gaseous phase in a relatively more soluble solid particulate form. The invention further provides for a crystalline Form-VI () of nevirapine having an X-ray diffraction pattern of (2-theta values in degrees) 9.2953, 11.2023, 12.7019, 12.9796, 13.5273, 15.4670, 17.2597, 19.1038, 19.7267, 21.1303, 22.9381, 25.5589, 26.4913, 27.2150, 27.7283, 29.7134, and 33.8343 degrees two theta. The invention further provides for the preparation of microspherical and/or nanospherical Form-V () and crystalline Form-VI () of nevirapine as well as novel dosage forms including parenteral-, inhalant-, transdermal- and oral dosage forms.

Method for increasing the solubility of nevirapine

This invention relates to a macrolide composition, more particularly an amorphous form (Form-III) of 3R, 4S, 5S, 6R, 7R, 9R, 11S, 12R, 13S, 14R-6-[(2S,3R,4S,6R)-4-dimethylamino-3-hydroxy-6-methyloxan-2-yl]oxy-14-ethyl-7,12,13-trihydroxy-4-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy-10-(2-methoxyethoxymethoxyimino)-3,5,7,9,11,13-hexamethyl-1-oxacyclotetradecan-2-one or roxithromycin characterized by the absence of peaks in the infra-red spectrum of amorphous (Form-I11) of roxithromycin at 3577.15; 3526.03; 3465.27 and 3276.24 cm-1 relative to the infra-red spectrum of the prior art roxithromycin raw material displaying peaks at 3577.15; 3526.03; 3465.27 and 3276.24 cm-1 and further characterized by an increased solubility of at least 50% over prior art anhydrous and monohydrated roxithromycin in acetate buffer (pH 4.5), phosphate buffer (pH 6.8) and water.

Amorphous roxithromycin composition

The invention relates to an amorphous non-crystalline glass form (Form-II) of 3R,4S,5S,6R,7R,9R,11S,12R,13S,14R-6-[(2S,3R,4S,6R)-4-dimethylamino-3-hydroxy-6-methyloxan-2-yl]oxy-14-ethyl-7,12,13-trihydroxy-4-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy-10-(2-methoxyethoxymethoxyimino)-3,5,7,9,11,13-hexamethyl-1-oxa-cyclotetradecan-2-one or roxithromycin having at least one characteristic infra-red spectrum peak at approximately 3580 to 3464 cm. The invention further relates to a preparation method of increasing the solubility of roxithromycin including the steps of selecting anhydrous roxithromycin or monohydrated roxithromycin; elevating the temperature of the roxithromycin to above the melting point thereof; and reducing the temperature of the melt sufficiently to allow it to set into an amorphous non-crystalline glass form (Form-II) of roxithromycin having relatively increased solubility without decreasing the stability of thereof.

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Potchefstroom, South Africa

Wilna Liebenberg