Simultaneous estimation of degree of crystallinity in combination drug product of abacavir, lamivudine and neverapine using X-ray powder diffraction technique

Objective: In the present study, simultaneous determination of degree of crystallinity content in abacavir (ABC), lamivudine (3TC) and neverapine (NVP) from there combination drug product using X-ray powder diffraction (XRPD) technique is developed and validated. Methods: The X-ray procedure for the identification and determination of the degree of crystallinity in ABC, 3TC and NVP drug product is developed and validated. It is based on the X-ray diffraction from crystalline region of the drug product. The characteristic peaks of the three drugs were characterized using XRPD. Results: ABC, 3TC and NVP concentrations ranging from 70% to 130% in drug product were prepared and linearity in this concentration range is described. The % coefficient of variation (%CV) was found to be 0.9982 for ABC, 0.9978 for 3TC and 0.9984 for NVP. The mean recoveries were found to be 100.3% for ABC, 99.0% for 3TC and 100.8% for NVP. Regressions statistics and Analysis of variance (ANOVA) table results were evaluated and found to be satisfactory. Conclusions: The method has been applied to unknown mixtures of drug formulations and stability samples. The proposed method can be useful in the quality control of combination drug products.