Drying of drug-containing particles

摘要

A secondary drying process is disclosed for removing residual solvent from drug-containing particles that have been formed by solvent-based processes, the secondary drying process utilizing a combination of vacuum, agitation, and a stripping gas.

主权项

1. A process for producing a pharmaceutical composition, comprising the steps:
(a) forming a solution comprising a drug, an excipient and a solvent; (b) in a spray drying apparatus, atomizing said solution into droplets and removing at least a portion of said solvent from said droplets so as to form at least partially noncrystalline drug-containing particles containing less than about 10 wt % of said solvent; and (c) conducting a secondary drying of said drug-containing particles of step (b) by
(i) removing the drug-containing particles from the spray drying apparatus and introducing said drug-containing particles of step (b) into a secondary drying apparatus having an external wall, the secondary drying apparatus being a separate chamber from the spray drying apparatus;(ii) circulating said drug-containing particles within said secondary drying apparatus by means of a mechanical agitator independent of said wall;(iii) flowing a stripping gas through said secondary drying apparatus while reducing a total pressure to and maintaining the total pressure, within said secondary drying apparatus at less than about 0.75 atm;(iv) conducting the secondary drying step for about 30 minutes to about 20 hours to remove solvent from the drug-containing particles such that the drug-containing particles contain less than about 0.5 wt % of the solvent; and(v) removing said stripping gas and at least a portion of said solvent from said secondary drying apparatus.