Design and statistical optimisation of praziquantel tablets by using solid dispersion approach

Abstract

Aim: The present investigation was carried out with an aim to formulate and evaluate praziquantel (PZQ) tablets using
solid dispersion approach. Methodology: The solid dispersion was prepared by solvent evaporation method using carriers such as mannitol, urea and PEG 6000 with drug: Carrier ratio of 1:1, 1:2 and 1:3.The solid dispersion was evaluated for physical parameters such as angle of repose, bulk density, Carr’s index, Hausner ratio, drug content and in vitro drug release studies. PZQ tablets (100 mg drug) were prepared further from solid dispersions using direct compression technique.

 Results: The results of individual assays of solid dispersions with different ratios revealed that the 1:2 ratio of PZQ with
PEG 6000 showed higher dissolution rates when compared to others. Tablets compressed were evaluated for their physical
parameters such as weight variation, thickness, hardness, friability, dissolution, and disintegration tests and compared with
plain drug and marketed formulation (Biltricide 600 mg Bayer HealthCare Pharmaceuticals). In vitro dissolution profile
of optimized batch (F8) showed better release. The highest solubility was shown by tablet prepared from solid dispersion
with 1:2 ratio of PZQ: PEG 6000, which was found to be more than plain drug. Infrared spectra showed that the functional
groups of PZQ and PEG 6000 were preserved. Results of 23 factorial designs affect the dependent variables such as hardness,
disintegration time and % friability. Conclusion: It was concluded that by adopting a systematic formulation approach
one can reach to an optimum level. Hence, solid dispersion formulation using PEG 6000 carriers was found to be a good
alternative approach for increasing the dissolution rate of PZQ tablets in distilled water.

Key words: Carriers, dissolution, optimization, praziquantel, solid dispersion