*Corresponding Author: Seema Rohilla, Email: seema.rohilla4@gmail.com ISSN 0976 – 3333 REVIEW ARTICLE Available Online at www.ijpba.info International Journal of Pharmaceutical & Biological Archives 2012; 3(4):727-731 Biowaivers: Criteria and Requirements Seema Rohilla *1 , Ankur Rohilla 2 , Arun Nanda 3 1 Hindu College of Pharmacy, Sonepat-131001, Haryana, India 2 Department of Pharmaceutical Sciences, Shri Gopi Chand Group of Institutions, Baghpat-250609, UP, India 3 Faculty of Pharmaceutical Sciences, Maharishi Dayanand University, Rohtak-124001, Haryana, India Received 28 Mar 2012; Revised 10 July 2012; Accepted 17 July 2012 ABSTRACT A biowaiver has been regarded as an official approval of the waiver for conducting a bioequivalence study in the context of an application for drug approval process. Bioequivalence is an important parameter in the process of drug development that is needed to be performed when there is a change in the formulation of dosage form. It has been widely accepted that the in vitro tests for solubility, permeability and dissolution form the basis of a drug product's classification and qualification for biowaivers. The biopharmaceutics classification system (BCS) is a scientific approach for classifying drug substances based on their dose/solubility ratio and intestinal permeability. BCS has been widely implemented for waiving bioequivalence studies on the basis of the solubility and gastrointestinal permeability of drug substance. Hence, BCS-based biowaiver has become an important and cost-saving tool in approval of generic drugs. The present review critically aims to discuss various criteria and requirements for conducting biowaiver study alongwith various data to support request for biowaivers. Key words: Biowaiver, Bioequivalence, Biopharmaceutics. INTRODUCTION Biowaivers are considered as the waivers of clinical bioequivalence studies [1,2] . Bioequivalence studies are as vital concern in drug development process, which are required for small changes in drug products that develop during drug development to ensure that the dosage forms prove to be safe and effective [3] . Moreover, bioequivalence has proven even more significant in case of drugs with narrow therapeutic index (NTI). The bioequivalence studies are required for the clinical development of new chemical entities (NCE), when the formulation of the pharmaceutical dosage form has been changed. The in vivo pharmacokinetic data can be used as an important constraint for in vivo solubility and permeability data [3,4] . As it is estimated that the in vivo bioavailability and bioequivalence studies cost up to $ 250,000 each and require up to 2 months to complete, whereas, the in vitro laboratory tests are rather inexpensive and fast, in which dissolution studies, similarity factor (f2) profile calculations and report writing represent a large part of the laboratory work [5] . Hence, it has been widely accepted that the biowaivers typically save time and cost. The U.S. FDA, European Medicines Agency (EMEA) and Japanese Pharmaceuticals alongwith Medical Devices Agency (PMDA), possess biowaiver guidance documents. It has been reported that recent FDA guidance permits the waiver of additional in vivo studies for pharmaceutical products that meet specified criteria. Thus, the costly and time consuming in vivo studies may be replaced by fast and low cost in vitro tests [6] . Furthermore, the BCS has appeared as a supportive means in product development by evading to the in vivo performance of the active substance [7] . The bio- relevance of the BCS properties and the in vitro release are expressed through a correlation between in vitro and in vivo data. Recently, BCS has been executed for waiving bioequivalence studies on the basis of the solubility and gastrointestinal permeability of drug substance, which can be strategically deployed to save time and resources during generic drug development [8] . Moreover, BCS has been developed to allow prediction of in vivo pharmacokinetic performance of drug products from measurements of permeability and solubility. In addition, the BCS has been adopted as a useful tool for in vivo drug