Cilnidipine

The stability of drug product or a drug substance is a critical parameter which may affect purity, potency and safety. The stability indicating method is that employed for the analysis of stability samples in pharmaceutical industry. Forced degradation studies show the chemical behavior of the molecule which in turn helps in the development of formulation and package. Forced degradation is a degradation of new drug substance and drug product at conditions more severe than accelerated condition. Thus, this review discuss the current trends in performance of stability indicating method to force degradation by providing strategy for conducting studies on degradation mechanism Stability testing by reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been performed of cilinidipine and olmesartan. All the drugs were separated. The retention time of cilinidipine and olmesartan was founded respectively. Ranges of 50 -300μg/ml for cilinidipine and 25 – 150 μg/ml for Olmesartan. Keyword: Olmesartan, Cilnidipine, RP-HPLC.

The major problem in formulation of oral films of cilnidipine is that it belongs to BCS Class II moiety. Pharmacologically Cilnidipine is a dihydropyridine (DHP) type of calcium channel antagonist. Unlike other calcium channel antagonists, Cilnidipine blocks the influx of Ca2+ ions into both vascular smooth muscle at the level of L-type Ca2+ channels and neuronal cells at the level of N-type Ca2+ channels. Cilnidipine was absorbed over 2 hours and its bioavailability is 64-90%. Hence there is a need to increase the solubility and oral bioavailability of cilnidipine by formulating it in to solid dispersions and incorporating the same in to the formulation of fast dissolving films which gives fast onset of action. Nine formulations (FC 1 - FC 9) of cilnidipine films were prepared and evaluated for their physical characteristics such as thickness, weight variation, folding endurance, drug content uniformity and gave satisfactory results. The compatibility of the drug in the formulation was confirmed by FTIR and DSC studies. The formulations were subjected to disintegration, in vitro drug release studies and formulation FC 6 was found to be best formulation which contain HPMC, PVP as film forming polymers along with cilnidipine solid dispersion with poly ethylene glycol at weight ratio of 1:4 showed excellent film forming characteristics such as disintegration time of 49.3 sec and percentage drug release 97.92 within 8 minutes.

A simple, accurate, and precise UV spectrophotometric method has been developed and validated for simultaneous estimation of Cilnidipine and Valsartan in synthetic mixture. The estimation of drugs was done by Second Order Derivative spectrophotometric method using 219 nm and 227 nm wavelength. Methanol was used as a solvent. The Linearity was obtained in the concentration range of 2-10 µg/ml for Cilnidipine and 5-25 µg/ml for Valsartan with R2 0.9994 and 0.9980 respectively. Accuracy was determined by recovery studies and showed % recovery between 98 to 102 % for both the drugs. The LOD and LOQ values of Cilnidipine were found to be 0.33 and 1.01 and for Valsartan values were found to be 0.18 and 0.55. The developed method was validated as per the ICH Guidelines Q2 (R1).