Experimental Device Provides Chemotherapy Regulation

A team of engineers at Stanford University recently developed a technology that can monitor drug levels in the body, which could be used to prevent overdoses.

Since each person metabolizes medication differently, it can be difficult to determine the most effective dose of certain drugs, such as chemotherapy or insulin. The newly created tool would make it easier for individuals to receive the proper dose and take out any of the guesswork involved, according to the investigators.

In a study published by Nature Biomedical Engineering, the authors were able to regulate chemotherapy in animal models using an experimental device.

“This is the first time anyone has been able to continuously control the drug levels in the body in real time,” said researcher H. Tom Soh, PhD. “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 device includes a real-time biosensor to monitor drug levels in the blood, a control system that calculates the proper dose, and a pump that delivers the right dose of the drug.

The biosensor contains aptameters (molecules) that bind to a specific drug. When the aptameter senses the drug, it changes shape, which is detectable by an electric sensor. The shape of the aptameter depends on the concentration of the drug in the bloodstream, according to the study.

The aptameter changes are captured every few seconds and is connected to software that controls the pump.

In the study, the authors delivered doxorubicin chemotherapy to animals. They noted that the animals were able to maintain a constant dosage of the drug, despite physiological and metabolic differences, according to the study.

The investigators also assessed the device’s ability to account for potential drug interactions. The authors introduced a drug known to spike or dip chemotherapy levels and found that the novel device was able to stabilize drug levels, according to the study.

If proven in humans, this device could have a significant clinical impact.

“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?” Dr Soh said.

This would allow investigators to develop an electronic system to replace pancreatic function in patients with type 1 diabetes, according to the study.

“Now that is an exciting future,” Dr Soh said.

While there are years of testing required to determine the safety and efficacy of this device for humans, the authors believe it represents major progress for personalized medicine.

Currently, physicians know different individuals react differently to drugs and the addition of other drugs can change drug effects, but there is no tool to account for these variables.

“Monitoring and controlling the actual dosage a patient is receiving is a practical way to take individual factors into account,” Dr Soh said.

This new technology would be especially useful for pediatric patients with cancer whose metabolism is drastically different than adults.

In the future, the authors plan to miniaturize the device so it could be easily implanted or worn by the patient. They are also testing the system with different aptamers to detect and regulate other biomolecules, the study concluded.