Stabilized, sprayable emulsion containing active agent particles

Inventors

Dann, Thomas • Nelson, Renee • Wagner, Brian • Walter, Mary

Assignees

FORMULATED SOLUTIONS LLC • Mission Pharmacal Co

Abstract

A sprayable emulsion is provided. The emulsion can be used in the treatment of various skin conditions. The emulsion includes a hydrofluoro-based propellant, an emulsification system, an oil phase, a water phase, and active agent particles. Further, the emulsification system includes at least one nonionic emulsifier. The emulsion has a viscosity ranging from about 500 centipoise to about 10,000 centipoise and a hydrophilic to lipophilic balance (HLB) value of from about 2 to about 12. The present inventors have found that by selectively controlling the nature of the emulsification system and the viscosity of the emulsion, the active agent particles resist settling such that a substantially homogeneous distribution of the active agent particles is maintained and can be evenly sprayed onto a surface without running once applied.

Core Innovation

The invention relates to stabilized sprayable emulsions for topical skin treatment that include a hydrofluoro-based propellant, an emulsification system, an oil phase, a water phase, and active agent particles. The emulsification system includes at least one nonionic emulsifier and is defined to include one or more nonionic lipophilic emulsifiers and one or more nonionic hydrophilic emulsifiers.

The core formulation concept uses an emulsification system based on nonionic lipophilic emulsifiers and nonionic hydrophilic emulsifiers having an HLB value of from about 2 to about 12 and a viscosity ranging from about 500 centipoise to about 10,000 centipoise. By selecting nonionic lipophilic emulsifiers and nonionic hydrophilic emulsifiers within a weight ratio range from about 10 to about 20, the sprayable emulsion maintains homogeneous distribution of the active agent particles and resists settling of the active agent particles in the emulsion.

The invention also covers forming the sprayable emulsion by forming a base emulsion composition containing the active agent particles, the emulsification system, the oil phase, and the water phase, and then introducing this base emulsion into a spray container. A hydrofluoro-based propellant is injected into the container so that the resulting sprayable emulsion has the specified viscosity and HLB value, while maintaining the emulsification system composition relationships, including the weight ratio of nonionic lipophilic emulsifiers to nonionic hydrophilic emulsifiers.

Claims Coverage

The document contains two independent claims directed to a sprayable emulsion formulation and a method of forming the sprayable emulsion. The claims are anchored by the same core constraints on viscosity, HLB value, and a defined weight ratio between nonionic lipophilic and nonionic hydrophilic emulsifiers, with the method additionally reciting container introduction and hydrofluoro-based propellant injection.

Claim coverage centers on hydrofluoro-based sprayable emulsions defined by a nonionic emulsification system having both nonionic lipophilic and nonionic hydrophilic emulsifiers, with the emulsion viscosity and HLB value constrained to about 500–10,000 centipoise and about 2–12, respectively, and with a nonionic lipophilic-to-hydrophilic emulsifier weight ratio of about 10–20. The method claim recasts the same formulation constraints into forming a base emulsion, loading it into a spray container, and injecting the hydrofluoro-based propellant to obtain the defined emulsion.

Stated Advantages

Documented Applications