Formulation design and optimization of Sustained release matrix tablets of zidovudine by using experimental design
Author (s): Gourishyam Pasa *1, Arun Kumar Kar 1
1Department of Pharmaceutical Technology, Royal College of Pharmacy and Health Sciences, Andhapasara Road, Berhampur, Odisha.
|Zidovudine (AZT), the first anti-HIV compound approved for clinical use is widely used for treatment of AIDS either alone or in combination with other antiviral agents. However, the main limitation to therapeutic effectiveness of AZT is its, low therapeutic index, short biological half-life, and poor bioavailability. The biological half-life of AZT-triphosphate is 4 hours, thus necessitating frequent administration (3 to 4 times a day) to maintain constant therapeutic drug levels. The aim of the present study is Formulation Design and Evaluation of oral matrix tablets of zidovudine by using Experimental Design. A rationale for developing zidovudine dosage form Sustained release allows delivery of a specific drug at a programmed rate that leads to drug delivery for a prolonged period of time. This improves bioavailability of the drug, reduces frequency of dosing, thus minimizing side effects and increase safety margin. In the present study, the oral matrix tablets of zidovudine were formulated by Experimental design by using combination of natural polymers (Xanthan gum/ Sodium alginate) as the retardant polymers each with three different levels. From FTIR results, confirm the absence of chemical interaction between the drug with the excipients used in tablet formulations. Also, there was no shift in the endotherm of in the drug- excipients mixtures indicating compatibility of drug with all the excipients. Matrix tablets were prepared by direct compression method and prepared tablets were evaluated for weight variation, percentage friability, hardness and drug content studies. All the formulations showed compliance with pharmacopeia standards. In vitro release studies revealed that, the formulation ZXA4 sustained release of drug for 12 hrs with 22% release of drug after 1hr and more than 96% at the end of 12 hrs.|
Keywords: Matrix tablets; experimental design; zidovudine; xanthan gum; sodium alginate.