Drug-fatty acid salt with wax-like properties employed as binder in melt granulation

The tacky and deformable properties of a wax-like drug-fatty acid salt, pro pranolol oleate (POA), make particle size reduction and separation challeng ing. The aim of this study was to investigate the use of POA as binder in a melt granulation procedure to improve processing properties. POA is a suit able candidate for binder phase in melt granulation with a melting temperat ure of 50 56 degreesC. Small batches (ca 30 g) were manufactured using a hi gh shear mixer with lactose monohydrate as the substrate phase. Optimum uni formity of drug content and minimum friability were found at 10% w/w POA bi nder concentration. POA melt granules exhibited a > 10-fold increase in the rate of in vitro dissolution at pH 7.4 with 0.2% w/v sodium lauryl sulphat e compared with raw POA. The increased drug surface area in granular form w as thought to be responsible for the change in dissolution behaviour. This study has demonstrated that melt granulation using POA as binder is a viabl e process which leads to beneficial changes in dissolution behaviour for th e lipophilic drug-fatty acid salt. (C) 2000 Elsevier Science B.V. All right s reserved.