Tecnologia experimental monitoriza e mantém níveis de fármacos no corpo.
"As with coffee or alcohol, the way each person processes medication is
unique. One person's perfect dose may be another person's deadly
overdose. With such variability, it can be hard to prescribe exactly the
right amount of critical drugs, such as chemotherapy or insulin.
Now, a team led by Stanford electrical engineer H. Tom Soh and
postdoctoral fellow Peter Mage has developed a drug delivery tool that
could make it easier for people to get the correct dose of lifesaving
drugs. In a paper published May 10 in Nature Biomedical Engineering, the
group showed that the technology could continuously regulate the level
of a chemotherapy drug in living animals.
"This is the first time
anyone has been able to continuously control the drug levels in the
body in real time," Soh said. "This is a novel concept with big
implications because we believe we can adapt our technology to control
the levels of a wide range of drugs."
The new technology has
three basic components: a real-time biosensor to continuously monitor
drug levels in the bloodstream, a control system to calculate the right
dose and a programmable pump that delivers just enough medicine to
maintain a desired dose.
The sensor contains molecules called
aptamers that are specially designed to bind a drug of interest. (These
aptamers are a focus of Soh's lab.) When the drug is present in the
bloodstream, the aptamer changes shape, which an electric sensor
detects. The more drug, the more aptamers change shape.
That
information, captured every few seconds, is routed through software that
controls the pump to deliver additional drugs as needed. (...)
The group tested the technology by administering the chemotherapy drug
doxorubicin in animals. Despite physiological and metabolic differences
among individual animals, they were able to keep a constant dosage among
all the animals in the study group, something not possible with current
drug delivery methods. (...)
If the technology works as well in
people as in their animal studies, it could have big implications, Soh
said. "For example, what if we could detect and control the levels not
only of glucose but also of insulin and glucagon that regulate glucose
levels?" he said. That could allow researchers to create an electronic
system to replicate the function of the dysfunctional pancreas for
patients with type 1 diabetes. "Now that is an exciting future," Soh
said.
Many years of tests lie ahead to ensure that this
technology is safe and effective for people, but the researchers believe
it may be big step toward personalized medicine. (...)
"Monitoring and controlling the actual dosage a patient is receiving is a
practical way to take individual factors into account," said Soh. (...)
The team plans to miniaturize the system so that it can be implanted or
worn by the patient. (...) The current setup might be suitable for a
chemotherapy drug, but not for continual use. The group is also adapting
this system with different aptamers so that it can sense and regulate
the levels of other biomolecules in the body."
Comentário de Rui Carrilho: O
corpo de cada pessoa é único, assim como a sua capacidade de
processamento de substâncias químicas. Deste modo, cada paciente reage
de modo diferente a medicamentos, como insulina ou quimioterapia. Com
tal variabilidade, torna-se difícil prescrever quantidades
exatas de medicamentos de modo a terem o efeito desejado. Para resolver
este problema, uma equipa de Stanford criou um equipamento de
administração de fármacos que consegue monitorizar e ajustar em tempo
real o nível de um certo medicamento no corpo de animais vivos. Este
dispositivo funciona à base de aptameros, moléculas que se ligam a
fármacos e, consoante a sua concentração no sangue, emitem sinais
elétricos diferentes que podem ser captados por um sensor. Esta
tecnologia, possivelmente revolucionária, poderia mudar a vida de
pacientes com diabetes, ou com outra condição médica que necessitasse de
medicação controlada permanente. Ainda faltarão muitos anos para
chegar, mas poderá ter um potencial tremendo para a medicina
personalizada.
Comentários
Enviar um comentário