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.
Concept of Orodispersible or Mucoadhesive “Tandem Films” and Their Pharmaceutical Realization
Orodispersible or mucoadhesive films as a patient-oriented dosage form for low-dosed drugs are usually produced using solvent casting. This paper presents a modification of the solvent casting technique that aimed to divide oral films into two or more compartments. The proposed objectives and fields of applications include improved handling properties and safety of application, the optimization of drug release kinetics and the enhancement of long-term stability when combining two or more active pharmaceutical ingredients into one oral film. A feasibility study for the combination of different film-forming polymers to generate the so-called tandem films was performed. As examples of practical implementation, orodispersible applicator films consisting of a drug-loaded section and a handheld piece were cast, and mucoadhesive buccal tandem films were cast to optimize the dissolution rate of the films.
Externally Triggered Drug Delivery Techniques Using Micro and Nanoparticles
The need for sustained and better-controlled drug administration has led to development of novel drug delivery systems. The concentration of a drug in blood at any given time depends on the prescribed routine of drug intake. Conventional methods of drug intake do not always maintain the required consistent drug concentration. Controlled drug release mechanisms can help in maintaining drug dosage levels while optimizing therapeutic effects. Microparticles and nanoparticles, initially developed as carriers for vaccines and anticancer drugs, are being used in drug delivery systems for drug targeting, improved release profile and efficiency. The drugs can be encapsulated inside the particles, suspended in or with them. However, release of the drug depends on the type of techniques used to trigger drug delivery. This review outlines the major techniques used for drug delivery applications based on external triggering mechanisms while utilising micro and/or nanoparticles. These techniques include ultrasound, light, radiofrequency, electric and magnetic field exposures. Most of these techniques have largely remained in vitro owing to challenges concerning safety due to exposure levels and penetration of external signals due to human physiology. Considering these aspects of the challenge, microwave based external triggering can be a prospective technology for drug delivery using micro and nanoparticles.