Study on Oxcarbazepine Half-tablet Preparation by Reciprocating Cylinder Method and Partial Dose Evaluation

OBJECTIVE To establish a reciprocating tube dissolution method to investigate the similarity of in vitro dissolution behavior of oxcarbazepine scored tablet preparations between the original and generic drugs, and to evaluate the differences in dose-specific pharmaceutical properties between the original and generic drugs. METHODS Using 250 mL of pH 1.2 hydrochloric acid solution, pH 4.5 acetate buffer, pH 6.8 phosphate buffer, and water(all 0.5% sodium dodecyl sulfate) as the dissolution medium, and reciprocating frequency of 10 dip min^-1, using a reciprocating tube dissolution device to determine the dissolution curves of generic drugs and original research drugs, and combining the similarity factor(f₂) method to evaluate the similarity of dissolution behavior between generic drugs and original research drugs, and compared the result with paddle method. The friability, weight variation and loss of mass of half-tablets were determined by friability tester and electronic balance through splitting by hand and by the cutting device respectively. RESULTS The f₂ of generic drug A in 4 dissolution medium were higher than 50 and showed its similarity to original drug. While the generic drug B was not consistent with the dissolution behavior of original drug as its f₂ factorswere all less than 50 in 4 dissolution. The post-segmentation weight variation, loss of mass and fragility of generic drug A and B were higher than those of the original drug. CONCLUSION The dissolution curve of oxcarbazepine half tablet preparation measured by the reciprocating cylinder method has good discrimination compared to the paddle method, and there is still a certain gap in the quality control of the generic drug in different doses compared to the original research drug.