http://informahealthcare.com/ddi ISSN: 0363-9045 (print), 1520-5762 (electronic) Drug Dev Ind Pharm, Early Online: 1–8 ! 2014 Informa Healthcare USA, Inc. DOI: 10.3109/03639045.2013.871551 RESEARCH ARTICLE Freeze drying: exploring potential in development of orodispersible tablets of sumatriptan succinate Dalapathi Gugulothu, Preshita Desai, Pranav Pandharipande, and Vandana Patravale Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N. P. Marg, Matunga, Mumbai, India Abstract The present investigation is aimed at development and characterization of sumatriptan succinate orodispersible tablets (ODTs) prepared by freeze drying technology. The tablet excipients were screened and the composition was optimized based on parameters which involved general appearance, tablet size and shape, uniformity of weight, mechanical properties, surface pH, moisture analysis, drug content, wetting time, in vitro and in vivo disintegration time. Furthermore, fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron micrograph of cross-section of the tablet and in vitro dissolution studies were performed. Studies revealed that formulation containing gelatin–mannitol (3.75% w/v and 3.5% w/v, respectively) with camphor as a volatile pore forming agent exhibited superior properties with disintegration time of less than 10 s. Furthermore, in vitro release studies revealed 90% release of drug from developed dosage form within 10 min, thus suggesting rapid drug dissolution followed by faster onset of action, which forms a strong rationale for development of ODTs of sumatriptan succinate. The developed technology is simple, which involves few steps and can be easily scaled up. Thus, it holds enormous potential for commercial exploitation. Keywords Gelatin, in vitro disintegration time, in vitro drug release, lyophilization technology, scanning electron microscopic analysis History Received 14 July 2013 Revised 12 November 2013 Accepted 17 November 2013 Published online 3 January 2014 Introduction Conventional tablets and capsules occasionally cannot be easily administered to certain group of patients, including, those with swallowing difficulties, geriatric, paediatric, bedridden and men- tally challenged patients 1–7 . Thus, patient compliance-oriented research has resulted in bringing out many safer and newer drug delivery systems and orodispersible tablets (ODTs) are one such example. The major advantages of this dosage form are admin- istration without water, high degree of content uniformity, quick onset of action, enhanced bioavailability and stability 8–17 . Furthermore, fast onset of action makes them lucrative for therapy modules wherein immediate medical intercession is essential for, e.g. in angina pectoris, migraine, acidity etc. 1 Thus, such readily administrable dosage forms have wedged the attention of the pharmaceutical industry owing to their expedi- ency in use. ODTs are also identified by varied terminologies, namely mouth dissolving tablets, fast dissolving/disintegrating tablets, melt in mouth tablets, rapid melts, quick dissolving tablets, rapidly disintegrating tablets and porous tablets. United States Food and Drug Administration (USFDA) has defined such dosage forms as a solid dosage form containing medicinal substances which disintegrates rapidly, usually in matter of seconds, when placed upon the tongue. European Pharmacopoeia (EP, 4th edition) has accepted the term OD for official usage 18 . Owing to their suitability in use; ODTs are mainly being explored for treatment modules of dysphagia, geriatrics, paediatrics, bedridden or disabled patients and for patients who have little or no access to water 8,19,20 . Various techniques employed for development of ODTs include freeze drying technology, mass extrusion, direct com- pression using super-disintegrant, tablet molding, etc. 21 , amongst which the freeze drying/lyophilization technology is compara- tively a recent addition to ODT manufacturing; wherein the frozen drug solution or suspension containing structure forming excipi- ents is subjected to vacuum that results in the removal of water by the sublimation and desorption process 22 . A new dimension can be added to ODTs developed by this technology by the addition of volatile ingredients, namely camphor, menthol which on removal during the process creates uniform porosity in the tablet that helps in further rapid disintegration upon contact with saliva. Sumatriptan succinate (Figure 1) belongs to triptan class of selective serotonin 5HT1B/1D receptor agonists medicinally indicated for treatment of migraine attack and cluster headaches. The underlying mechanism involves agonistic binding of drug sumatriptan to 5-HT receptor which leads to constriction of extra-cerebral blood vessels and thus inhibits the release of inflammatory mediators 23 . Currently, sumatriptan succinate is commercially available as oral tablets with varying strengths of 25, 50 or 100 mg, nasal spray (packaged in single-dose bottles containing either 5 or Address for correspondence: Prof. Vandana B. Patravale, Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, N. P. Marg, Matunga, Mumbai 400019, India. Tel: +91-22-3361 2217. Fax: +91-22-3361 1020. E-mail: vbp_muict@ yahoo.co.in Drug Development and Industrial Pharmacy Downloaded from informahealthcare.com by St Johns University on 01/04/14 For personal use only.