Regulator of the concentration of drugs in the blood
A new technology developed by Stanford University researchers working under the leadership of H. Tom Soh has provided monitoring and regulation of the level of the drug in the blood of animals. Its transfer to clinical practice will allow maintaining the optimal dose of the drug in the bloodstream without the risk of overdose or dose insufficiency, potentially life-threatening to the patient.
Each person is characterized by a unique rate of cleavage and excretion of chemical compounds, including drugs, from the body. Such variability makes it difficult to select the optimal dose, since the concentration ideal for one patient can be a dangerous overdose for another. This is especially true for life-saving medications such as insulin and chemotherapy.
A prototype biosensor designed to detect active levels of drugs in the bloodstream and is a component of a system for personalizing the dosage of drugs.
The new technology consists of three main components: a biosensor that provides continuous monitoring of the drug content in the bloodstream in real time, a monitoring system that calculates the correct dose, and a programmable pump that delivers an accurately selected dose of the drug to maintain the desired dose.
The sensor contains molecules known as aptamers, specially designed to bind the target molecule. When the drug is present in the bloodstream, the aptamer changes its shape, which is registered by an electric sensor.
This information, recorded every few seconds, is transmitted by software to the pump, which, if necessary, delivers an additional dose of the drug to the body. Such a system is called a closed control system that continuously monitors and simultaneously adjusts accordingly.
The developers tested the technology on rats and rabbits who were injected with the chemotherapeutic drug doxorubicin. Despite the physiological and metabolic differences between animals, they managed to maintain a stable dosage of the drug in the blood of all animals, which is practically impossible when using existing drug delivery methods. In addition, the researchers tested the system in conditions of acute drug-drug interaction, intentionally injecting animals with a second drug, which obviously causes strong fluctuations in the level of the chemotherapy drug. Under such conditions, the system also allowed to stabilize the levels of the drug, mitigating a potentially dangerous change in concentration for the body.
If the results obtained can be reproduced in clinical trials, a great future awaits the new technology. For example, it can be used to create an electronic system that reproduces the functions of the non-functioning pancreas of patients with type 1 diabetes mellitus.
There is still a lot of work to be done to verify the safety and effectiveness of the technology for humans, but researchers believe that this will be a big step towards personalized medicine. To date, doctors know that the same drug can act differently on patients with different genetic profiles. They also know that the simultaneous use of more than one drug can cause the development of undesirable drug interactions, but do not have the tools to combat this.
The existing prototype of the system is an external device resembling a "smart" system for intravenous administration, and the biosensor included in its composition is comparable in size to the size of a slide for microscopy. In this form, it can be used to regulate the dosage of chemotherapy drugs, but is not suitable for permanent wear. Therefore, the authors plan to miniaturize the system to a size that allows it to be implanted under the patient's skin.
Article by P. L. Mage et al. Closed-Loop Control of Circulating Drug Levels in Live Animals Stanford engineers create experimental technology to monitor and maintain drug levels in the body is published in the journal Nature Biomedical Engineering.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on Stanford University: Stanford engineers create experimental technology to monitor and maintain drug levels in the body.
18.05.2017