Design Development And Evaluation Of Controlled Release Formulations of Freely Water Soluble Drugs

Abstract

Controlled release (CR) oral drug delivery systems are most effective for maintaining newlineoptimal concentration of drugs with narrow therapeutic range and short elimination half- newlinelife. In CR products, plasma drug levels are achieved by immediate release of initial dose newlinefollowed by maintenance dose for a predetermined time. Cellulosic polymers such as newlinehydroxypropyl methylcellulose (HPMC) and ethylcellulose are widely used hydrophilic newlinepolymers for oral controlled drug delivery system. Their gel forming property, nontoxicity newlineease of compression, greater drug loading tendency, pH independent solubility and newlineflexibility to obtain desirable drug release profile. Drug release from these systems is the newlineconsequence of controlled matrix hydration, followed by gel formation, change of newlinetextural/rheological behavior, matrix erosion, and/or drug dissolution and diffusion. newlineDrugs from BCS classification I and III class were selected to demonstrate the matrix newlineformulation to achieve controlled release dosage form with different combinations of polymer. newlineLacosamide is classified as BCS class I and indicated as monotherapy in the treatment of newlinepartial-onset seizures with or without secondary generalization in adults, adolescents and newlinechildren from 2 years of age with epilepsy. The drug is first approved by US FDA on Oct newline28, 2008 with patent and exclusivity valid till 2023 and 2024. VIMPAT® in available in newlineimmediate dosage form ranging from 50mg,100mg, 150mg and 200mg as film coated newlinetablet twice a day. Lacosamide is rapidly and completely absorbed by the body following newlinefirst order kinetics. Tmax usually occurs between 1 and 4 h after administration and food newlinedoes not affect the rate or extent of absorption. Lacosamide has an elimination half-life of newlineabout 13 h, making it an ideal candidate for twice daily dosing with an immediate release newlineformulation. Controlled release formulations may therefore contribute to improved newlineoutcomes for epilepsy patients by providing better seizure control, whilst reducing the newlinepotential for adverse events. A once d