Self-nanoemulsifying drug-delivery systems for potentiated anti-inflammatory activity of diacerein.

BACKGROUND: Effective treatment of osteoarthritis necessitates both symptomatic relief and hindrance of joint degeneration progression. Non-steroidal anti-inflammatory drugs permit symptomatic relief only and can cause mucosal injury in the gut. Before absorption, diacerein (Dcn) is converted into rhein that counteracts cartilage degeneration without affecting prostaglandin production. Yet, low solubility and laxative action of unabsorbed rhein in the colon hindered its use. Thus, enhanced Dcn dissolution would allow absorption at the upper gut improving its bioavailability and possibly abolishing the laxative action. METHODS: Therefore, self-nanoemulsifying drug delivery systems (SNEDDSs) with each of gelucire 44/14 (Glc) and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) at different drug:carrier weight ratios of 1:1, 1:2, 1:4, 1:6, 1:8 and 1:10 were prepared by melt method and filled into hard gelatin capsules. The optimized binary systems were selected based on solid state characterization, scanning electron microscopy (SEM) and in vitro evaluation of the prepared SNEDDSs in comparison with their corresponding physical mixtures (PMs) and Dcn. The optimized systems were further examined with respect to their morphology, size distribution and ζ-potential. Moreover, the anti-inflammatory activity of the optimized systems against carrageenan-induced paw edema in rats was assessed through estimation of edema and edema inhibition percentages as well as histopathological examination and immunohistochemical localization of tumor necrosis factor-alpha (TNF-α) and caspase-3. RESULTS: Significantly (P<0.05) enhanced in vitro drug release was recorded for SNEDDSs with either carrier when compared to Dcn and the corresponding PMs. SNEDDSs based on 1:10 Dcn:Glc and 1:8 Dcn:TPGS showed significantly (P<0.05) reduced edema and inflammation as well as expression of TNF-α and caspase-3 relative to positive control and Dcn pretreated groups. CONCLUSION: These SNEDDSs can be represented as potential oral drug delivery systems of Dcn for enhanced dissolution and anti-inflammatory activity against carrageenan-induced paw edema.

Ion-exchange complex of famotidine: sustained release and taste masking approach of stable liquid dosage form.

A stable controlled release resinate-complex for the highly bitter taste famotidine (FAM) was developed to allow once-daily administration and improve patient compliance especially in pediatric and geriatric medicine. The drug-resinate complexes were prepared in different drug to resin (Amberlite IRP-69) ratios by weight (1:1, 1:2, 1:3, 1:4, 1:5 and 1:6). The optimized drug-resinate complex resulted from 1:6 drug to resin ratio experienced maximum drug loading and sustained release property. Hence, it was subjected to physicochemical characterizations by differential scanning colorimetry (DSC), x-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The optimized complex was further dispensed in the prepared syrup and the suspension was subjected to accelerated stability study, as mentioned in the International Conference on Harmonization (ICH) guidelines. Furthermore, the gustatory properties of the complex were evaluated on humans. The syrup complied successfully with ICH guidelines and sufficiently alleviated the bitterness of famotidine.