To make the targeted drug, the scientists combined the mineral magnetite with the enzyme urokinase, commonly used as a thrombolytic agent. The nanosized particles can then be localized around a blood clot using an external magnetic field. And the magnetite framework also acts as protection for the enzyme, which can be deactivated by inhibitors in the blood.
The combination demonstrated up to 4,000 times more efficiency than the enzyme-based drugs alone, according to the university, drastically reducing doses. Normally, the enzyme is administered in a “knock-out” dose to ensure a small portion reaches the clot; however, the targeted approach requires a much smaller (and less dangerous) amount.
The results of the in vitro study were published in the journal Scientific Reports.
“Now we are using a sledgehammer to crack a nut,” Ivan Dudanov of St. Petersburg’s Mariinsky Hospital said in a statement. “Dissolving a little blood clot that blocked a vessel of only 1-2 mm in diameter, thrombolytic drugs negatively affect the entire network of blood vessels. In order to change the situation, we decided to develop a method of targeted drug delivery that would allow us to considerably reduce the dosage and ensure that the whole therapeutic effect is focused on the clot.”
REFERENCE: Fierce Pharma; 28 JAN 2017; Michael Gibney