EP0551626A1 — Thermoreversible gel as a liquid pharmaceutical carrier for a galenic formulation

USPTO Abstract

There is disclosed a thermoreversible gel as a liquid pharmaceutical carrier for a galenic formulation having improved thermo-rheological properties and with a gelling temperature interval between about 25°C and 37°C, which comprises a) 10 to 30 wt.% of block copolymers of α-hydro-ω-hydroxypoly(oxyethylene)/poly(oxypropylene)/poly(oxy-ethylene) (Poloxamer) of the formula wherein a is at least 2 and b is at least 15 and the total portion of hydrophilic polyethylene units amounts to from 20 to 90 wt.% of the copolymer having a molecular weight from 1000 to above 16000; b) 0.01 to 5 wt.% of carboxyvinyl polymer (carbomer) having a molecular weight from 1 x 10⁶ to 4 x 10 ⁶; c) such an amount of a pharmaceutically acceptable base as necessary for adjusting the pH to a value between 4 and 8; d) 20 to about 85 wt.% of water, and e) optionally usual auxiliary agents. There is also disclosed a liquid galenic formulation containing a therapeutically active amount of an active substance and a thermoreversible gel as a liquid pharmaceutical carrier, the active substance being selected from the group consisting of β-lactamic antibiotics and other antibacterial agents, chemotherapeutics, antiinfectives, topical anesthetics, anti-inflammatory and analgesic agents, antifungal agents, coronary vasodilators, antiviral agents, miotics and anticholinergics, mydriatic agents, antiglaucoma agents, antihistaminics, biogenic peptides and cosmetic agents. At room temperature, such a formulation is in the sol form, which is converted into a gel form at a temperature about the body temperature and thus the application onto eye, skin and mucous membranes of the body cavities as well as the improved biopharmaceutical usefulness are made possible.