Orodispersible Films: A Systematic Patent Review.
BACKGROUND
Nowadays, Oral Film Technology (OFT) has gained much attention among all the oral drug delivery systems. Fast dissolving film, fast disintegrating film, and orodispersible film are some synonymous words for this dosage form. Without a need of liquid for administration, this dosage form dissolves in the mouth. Typically, fast dissolving film dissolves from 1 to 30 seconds.


OBJECTIVE
At the root of its originality, many researchers patented their work on the aspect of orodispersible films using different drugs, polymers, excipients and employing various methods of preparation. The review focuses on details related to orodispersible films and their patents from 1979-2017, collected from various sources like USPTO, Google patent, Espacenet, Intellectual Property India.


RESULTS
For the ease of discussion, collected patents are segregated on the basis of drugs, polymers, and method of preparation. It was found that many researchers are shifting towards fast dissolving films for better patient compliance, extended efficacy, high bioavailability, fast dissolution, and disintegration. With the help of polymers blend suitable for the drug release and improved method of preparation various parameters like tensile strength, thickness, and pH etc. can be controlled.


CONCLUSION
It was observed that judicial selection of polymers and polymers blends and methods of preparation are key parameters in the formulation of orodispersible film.
Formulation of Mouth Dissolving Strips of Metoprolol Succinate Using Locust Bean Gum
The current project was carried out to investigate the use of locust bean gum as a film forming agent in the development of fast dissolving oral strips that can be utilized for the drug administration in urgent situations such as convulsive seizures, hypertension and dysphasia. Oral strips of locust bean gum were formulated using solvent casting method containing metoprolol succinate as model drug. (T1- T9) placebo films were formulated initially using different concentrations of locust bean gum to assess the film forming ability of the locust bean gum. Crospovidone and PEG-200 were used as disintegrating agent and plasticizer respectively. Stability against moisture was improved by addition of beeswax. Formulated films (T1-T9) were evaluated for their appearance, film forming capacity, moisture permeability, weight variation and thickness. Placebo film formulations T4 and T6 consisting of locust bean gum (0.6 gm), beeswax (0.1 gm) and crospovidone (4%), 0.3 and 0.9 ml of PEG-200 respectively were selected for drug loading. Drug loaded films (F1 and F2) were characterised for parameters such as weight variation, film thickness, folding endurance, drug content uniformity, in vitro disintegration time, in vitro drug release, tensile strength and surface pH. Composition F2 comprising of locust bean gum (0.6 gm) and 0.9 ml of PEG- 200 was chosen as optimized formulation. Stability studies of optimized drug loaded formulation was done as per ICH guidelines of stability. Locust bean gum appears as a good alternative over the various synthetic polymers utilized in the formulation and development of oral strips/ films.
Formulation Development of Mouth Dissolving Film of Etoricoxib for Pain Management
Etoricoxib is a potent, orally active, and highly selective COX-2 inhibitor that exhibits anti-inflammatory, analgesic, and antipyretic activities. The present research was undertaken to develop mouth dissolving films of etoricoxib to have rapid onset of action. Mouth dissolving film (MDF) is a better alternate to oral disintegrating tablets due to its novelty, ease of use, and the consequent patient compliance. Solubility enhancement and taste masking of etoricoxib were the two challenges solved by formulating drug-inclusion complex with beta-cyclodextrin (BCD). MDF prepared by solvent casting etoricoxib-BCD complex along with HPMC as film forming polymer was found to possess desirable physicomechanical properties. In vitro release of etoricoxib from MDF in simulated salivary fluid and 0.1 N HCl was more than 95% within 2 minutes. Taste masking and in vivo disintegration were in acceptable range as assessed by human volunteers. Etoricoxib MDF was further characterized by differential scanning calorimetry, powder X-ray diffraction, and scanning electron microscopy. The index of analgesia shown by etoricoxib MDF was comparable to that of immediate release tablets (100% activity within 40 minutes) in animal studies. Conclusively, the present study documents the development of a commercially viable formula for an MDF of etoricoxib with rapidity in pain management.