Transdermal Therapeutic Systems
Design of the Transdermal Therapeutic Systems for Health Care Medicine and Medicine in Disasters
Tech Area / Field
- MED-DRG/Drug Discovery/Medicine
3 Approved without Funding
Scientific and Technical Center "Lekbiotech", Russia, Moscow
- Institute of Immunological Engineering, Russia, Moscow reg., Lyubuchany
- Johann Wolfgang Goethe-Universität / Institut für Pharmazeutische Technologie, Germany, Frankfurt am Main\nUniversitat Leipzig / Institut fuer Pharmazie-Pharmazeutische Technologie, Germany, Leipzig
Project summaryThe purpose of the Project is the designing new transdermal dosage forms with controlled release of drugs ensuring prolonged and continuous drug delivery and considerable reduction or elimination of the negative side effects of the drugs as compared to those in conventional dosage forms.
The task of the research is the elaboration of transdermal therapeutic systems (TTS) with the well-known drug substances: phenazepam (tranquilizer), diclofenac (non-narcotic analgesic, NSAID) and clonidine (antihypertensive agent). All TTS are based on the original hydrophilic adhesive matrix.
Fundamental bases of the research under the Project.
The controlled release technology allows to create TTS providing at single application continuous drug delivery to systemic blood circulation within several days. TTS allow to eliminate negative by-effects of drugs included into formulations due to the continuous delivery of low concentrations of drugs. TTS permit to avoid the first pass effect and, in some cases, to change the metabolism paths of drugs as compared to that when conventional formulations are used.
TTS is a functional analog of a medical dropping glass. They provide the delivery of required quantities of drugs in systemic blood stream. The rate of drug delivery can be adjusted for every patient according to inpiduals requirement in the drug and the drug permeability through the patient’s skin.
The TTS usage does not require patients immobilization and obligatory participation of medical staff. The work capacity of the patient during the medication is preserved. The atraumatic application of TTS permits to avoid microbial contamination.
The majority of TTS available in the world pharmaceutical market represents either membrane-type or “drug-in-adhesive” type. But the latter include hydrophobic matrices with rather low capacity and noticeable skin-irritation (excluding TTS with silicon matrices).
The presence of a membrane is justified only in the case, if the included drug has a narrow therapeutic range and considerable side effects. Membrane-type TTS are rather complex by built. The hydrophobic matrices in “drug-in-adhesive” TTS do not allow to achieve the high rate of drug delivery, because they do not produce epidermis hydration. The majority of hydrophobic matrices (e.g. the caoutchouc matrices) have their own skin-irritatative action.
Drug-in-adhesive TTS consist of a cover film, an adhesive matrix containing a drug, a skin permeation enhancer and a protective antiadhesion film which is removed before application. The material of the matrix is a pressure-sensitive adhesive.
The hydrophilic adhesive matrix created at STC “Lekbiotech” is suitable for transdermal delivery of the wide range of drugs having various chemical structures. The TTS, based on this matrix are fairly easy to produce. The hydrophilic matrix does not have its own skin-irritative effect due to the hydration of the epidermis under the patch. The drug diffusion coefficient in the matrix is rather high and considerable part of the drug is delivered from TTS according to zero-order kinetics. Therefore the patient’s skin serves as a rate limitation membrane in the course of transdermal drug delivery. The permeability of drugs through hydrated epidermis at any given moment for the given patient and the area of the patch determine the rate of drug delivery and the daily dose of the drug.
The research of the creation of TTS based on the original hydrophilic matrices has been carried out for about 10 years under the leadership of prof. A.E. Vasiliev. As a result about 10 TTS have been developed. Three of them have been adopted in Russia for medical application, and two of them (with glycerol trinitrate and isosorbide dinitrate) started to be produced.
The composition of the hydrophilic matrices in different TTS with different drugs varies insignificantly. The technology of their manufacturing and the equipment used are principally the same.
The good adhesive properties of the hydrophilic matrix provide a good attachment of TTS to human skin and painless removal of TTS. The hydrophilic matrix is a new step in designing of high capacity biocompatible TTS.
The realization of the Project will allow to design three new medical preparations for significant improving of the drug therapy and the life quality of chronic patients. Some of these drugs in TTS form can be used in medicine in disasters (e.g. TTS, containing phenazepam).
According to preliminary estimation the demand for the TTS with the above mentioned drugs is likely to come to 50-70 million of patches annually.
In the course of the Project realization chemical, physico-chemical, pharmaceutical and preclinical investigations are to be carried out. Pharmaceutical and technological documentation concerning the said three drugs in TTS form will be issued. Some papers will be published.
The participation in the Project of the staff consisting of more than 50% weapon scientists, will allow to involve these scientists in the research connected with the solution of international peaceful scientific problems in chemistry, pharmacy and biology.
The foreign collaborators will be carriers of the newest experience in the world science and will share their experience with Russian scientists, members of the Project. The collaborators may take part in the evaluation of the Project results.