Pharmaceutical compositions of roflumilast in aqueous blends of water-miscible, pharmaceutically acceptable solvents
The low aqueous solubility of roflumilast in parenteral preparations and topical emulsions, suspensions, gels or solutions can be improved by including a blend of water-miscible solvents in the pharmaceutical composition. The blend of water-miscible solvents can include diethylene glycol monoethyl ether (Tradename Transcutol®; abbreviated DEGEE) and water. The ratio of diethylene glycol monoethyl ether to water is from 1:10 to 20:1. The resulting composition has improved bioavailability and efficacy and can be used to inhibit phosphodiesterase 4 in a patient in need of such treatment.
1. A pharmaceutical composition consisting of roflumilast, white petrolatum, isopropyl palmitate, an emulsifier blend of cetearyl alcohol, dicetyl phosphate and ceteth-10 phosphate, hexylene glycol, N-methyl pyrrolidone, diethyl glycol monoethyl ether, methylparaben, propylparaben and water in the following proportions:
Roflumilast 0.5% w/w
White Petrolatum 10.0% w/w
Isopropyl Palmitate 5.0% w/w
Emulsifier blend 10.0% w/w
Hexylene glycol 8.0% w/w
N-methyl pyrrolidone 12.0% w/w
Diethylene glycol monoethyl ether 25.0% w/w
Methylparaben 0.2% w/w
Propylparaben 0.05% w/w
Purified Water q.s. ad 100.
2. A pharmaceutical composition consisting of roflumilast, white petrolatum, isopropyl palmitate, an emulsifier blend of cetearyl alcohol, dicetyl phosphate and ceteth-10 phosphate, hexylene glycol, diethyl glycol monoethyl ether, methylparaben, propylparaben, and water, in the following proportions:
Roflumilast 0.5% w/w
White Petrolatum 10.0% w/w
Isopropyl Palmitate 5.0% w/w
Emulsifier blend 10.0% w/w
Hexylene glycol 2.0% w/w
Diethylene glycol monoethyl ether 25.0% w/w
Methylparaben 0.2% w/w
Propylparaben 0.05% w/w
Purified Water q.s. ad 100
wherein said composition does not contain undissolved roflumilast.