Example 1: Formulation of an Aqueous Nasal Testosterone Formulation
A formulation of a testosterone ester was prepared using a combination of water and other additives which would help to solubilize the testosterone in the aqueous environment. The formulation was prepared by combining the testosterone with the first and second additives, Cremophor EL® and Neobee M5®, respectively, with stirring until all components dissolved. Distilled water which has been warmed to a temperature from about 65° C. to about 80° C. is added to the mixture of testosterone, Cremophor EL®, and Neobee M5®. The mixture was then brought to the phase inversion temperature followed by cooling until the mixture is clear. The mixture was be cooled at either ambient room temperature or using an ice bath to achieve clarity. The resulting emulsion was passed through a 0.22 micron Tuffryn® filter and collected in the administration container. The passage through the filter both sterilized the emulsion and imparts more consistency to the droplet size within the emulsion. Without being bound by theory, the filtration of the emulsion and the increased consistency may result in a more consistent kinetic absorption of the drug. The emulsion was then added to a nasal actuator for administration. The resultant emulsion was a nasally administrable testosterone formula containing 1.2% w/w testosterone propionate with 24% w/w Cremophor EL®, 5% w/w Neobee M5®, and 69.8% w/w distilled water. Additionally, a 2.2% w/w testosterone propionate formulation was prepared with 24.8% w/w Cremophor EL®, 14.3% Neobee M5®, and 58.7% w/w distilled water.