<b>Validated RP HPLC Method for the Determination of Nelaribine in Bulk and Tablet Dosage Form</b> A novel, simple and economic reverse phase high performance liquid chromatography RP HPLC method has been developed for the estimation of Nelaribine in bulk and tablet dosage form with greater precision and accuracy. Separation was achieved on Cosmiscil C18 column 150X4.6mm i.d.,5µm in isocratic mode using Triflouro acetic acid PH 3.6 buffer and Acetonitrile in the ratio of 90 10 v v as mobile phase, pumped in to the column at flow rate of 1.0 mL min 1and the detection of eluent from the column was carried out using variable wavelength UV detector at 248 nm. The total run time was 15 min and the column was maintained at ambient temperature. The retention time of Nelaribine was 4.003 min. The standard curves were linear over the concentration range of 25 150 µg ml with R2 0.999 and the LOD and LOQ values for Nelaribine were 0.04 µg ml and 0.12 µg ml , respectively. The percentage recovery was found to be 101.76 – 98.72 , the RSD was found to be 0.43. The percentage amount of a marketed tablet formulation of Nelaribine was found to be 101.2 . The method was validated as per ICH guidelines. Validation studies demonstrated that the proposed RP HPLC method is simple, specific, rapid, reliable and reproducible. Hence the proposed method can be applied for the routine quality control analysis of Nelaribine in bulk and tablet dosage forms. Nelaribine, RP HPLC, Method Development, Validation, ICH guidelines 513-522 Issue-4 Volume-1 Mrs.P.D.Chaithanya Sudha | Prof.D.Gowri Sankar