- Could you explain the difference between your preparation concept and those used in medicine now?
- As you know, a thrombus is a blood clot. In most cases, thrombin, the blood ferments, work for our good: they seal wounds by stopping the bleeding. But they can cause dangerous formations. Special medicinal enzymes help to destroy a blood clot in the human blood vessels. They react with plasminogen, converting it into plasmin, which affects thrombus lysis (cells, and their systems dissolution). However, the human immune system is wary of introduced enzymes. Therefore, modern drugs have just a few minutes to start the thrombolysis mechanism. After this time, the medication is leveled by immunity and stops working. Our preparation concept allows enzymes to stay in blood for much longer and to achieve the goal - destroy the blood clot.
- How have you achieved these results?
- Our preparation has an interesting story, which started in 1990. Then David Avnir, my good friend and the co-director of the Solution Chemistry of Advanced Materials and Technologies International Laboratory, the Hebrew University Professor, published an article which became a real breakthrough in science. He joined the "ceramics" and biomaterials - inorganic and organic substances - in the same structure. Professor Avnir developed a special approach, in which the inorganic material (he used silica, SiO2) «captured» enzymes. Imagine a firm ceramic cell (matrix), which includes living matter in complete safety. This significantly increased the resistance of biomaterials that are initially unstable. Most enzyme vaccines and drugs required storage at low temperatures. Now, their properties can be saved in less comfortable conditions for them.
Later, however, he acknowledged that developed biocomposites will hardly find real medicine application. According to the strict rules of the American Food and Drug Administrarion (FDA), which deals with the control standards of foods, cosmetics and medicines, silica can not be used in preparations that are parenterally administered, i.e. bypassing the gastrointestinal tract. However, these drugs are effective in the serious illnesses treatment. It would have taken at least 10 years of licensing to obtain FDA permission, so he entrusted his research rethinking to our laboratory.
Now about half of the studies that we carry out in the laboratory are related to nanocomposite materials. The same situation is with the development of new drug concepts for the thrombosis treatment case. We neither improve existing drugs and enzymes nor invent new ones, it's useless. We use the tissue-type plasminogen activator - the substance for the blood clots destruction used throughout the world. But we conclude enzyme at the inorganic porous "shell" – the alumina matrix. This is one of the two metal oxides approved for direct introduction into human blood. The immune system does not attack the injected product because it does not see the biomaterial in the alumina pores. The alumina itself is practically insoluble in a blood environment saturated with ions.
- Cardiovascular diseases are the leading cause of death worldwide. In Russia, such diseases result in fatal for 58-60% of the population. In our study, we work closely with Ivan Dudanov, a unique science-practitioner, specialist in vascular surgery, the head of the St. Petersburg regional vascular center. Search for the optimal treatment of fatal diseases like cancer, AIDS, tuberculosis occupies the minds of thousands of scientists around the world. But are the cardiovascular diseases less dangerous? Only 10-12% of people, according to Ivan Dudanov, recovering from a heart attack or stroke, are able to work; only 30% of them partially rehabilitate and can take care of themselves. We want to reverse the situation. Our drug can become a "biorobot" plying in blood, which finds a blood clot, gets rid of it and continues the service for a long time without any side effects. Also our drug may be a part of a vascular implant as a subcoating. This will allow people with artificial dentures not to take ineffective anticoagulant pills, which also have a negative impact on the human body.
- At what stage of the work are you now?
- We have conducted laboratory tests in the biological environment. Our product lasted a month in the high concentrated blood, which in fact is equivalent to a year of being in the human body. During this "year" the drug effectiveness decreased only by 2%. Just two days ago, several vascular prostheses with a layer of our preparation were sent to vivarium for the preclinical tests. In February, the first results are expected. If all goes well, this year we will be able to begin clinical trials. For now, only five people work in our laboratory, but we are doing everything we can for a new drug to start helping people as soon as possible.