SMEDDS of Olmesartan Medoxomil: Formulation, Development and Evaluation

International Journal of Research and Scientific Innovation (IJRSI) | Volume VI, Issue IX, September 2019 | ISSN 2321–2705

SMEDDS of Olmesartan Medoxomil: Formulation, Development and Evaluation

Shanisha Mehetre, Vishruti Kadam, Dr. Manisha Karpe, Dr. Vilasrao Kadam

Bharati Vidyaoeeth’s College of Pharmacy, C.B.D.Belapur, Navi Mumbai, India

Abstract: – The objective of the work was to develop and evaluate self-microemulsifying drug delivery system (SMEDDS) for improving the delivery of BCS class II antihypertensive agent, Olmesartanmedoxomil (OLM). The solubility of OLM in oils, cosurfactants, and surfactants was evaluated to identify the components of the microemulsion. The pseudoternary phase diagram was plotted to identify the area of microemulsion existenceat different Smix ratios (1:1, 2:1, 3:1) based on the results of solubility and emulsification studies. Smix ratio of 1:1 was selected for formulation of SMEDDS as the flowability of the formulation with Smix ratio of 1:1 was retained and it also gave a fairly larger microemulsion existence region. The in vitro drug release studies were carried out in phosphate buffer of pH 6.8 using USP XXIII dissolution testing apparatus type II at a paddle speed of 75 rpm. The optimized OLM liquid SMEDDS exhibited mean globule size of 59.91 nm, while experimental value was found to be 51.11 nm and polydispersity index of 0.42. The stability of OLM in SMEDDS was determined as per the International Conference on Harmonisation guidelines.

Keywords:- Olmesartanmedoxomil, SMEDDS, optimization, lyophilization

I. INTRODUCTION

Olmesartanmedoxomil (OLM) is a low dose, BCS Class II drug. It is an extensively used antihypertensive drug [1]. By the action of aryl esterases, situated in both intestine and plasma, it gets quickly de-esterified upon oral administration in to an active metabolite, i.e., olmesartan [1]. However, the oral bioavailability (BA) of OLM is only 26% in healthy humans due to low solubility in gastrointestinal fluids and unfavorable breakage of the ester drug to a poorly permeable parent molecule in the gastrointestinal fluids. OLM is highly lipophilic with a log P value of 4.31, which attributes to its poor aqueous solubility.
BCS Class II, which has low solubility and high permeability require solubility enhancement as an integral part of the formulation strategies [2]. Thus, SMEDDS are beneficial since it is a simple process and the drugs are in a pre-dissolved state and the energy input associated with a solid–liquid phase transition is avoided, thus overcoming the slow dissolution process after oral intake[2].

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