An implantable living pharmacy produces drugs in the body

Scientists at Northwestern University, Rice University, and Carnegie Mellon University have made a device that can be implanted under the skin to produce one or more drugs inside the body. The device was tested in rats and uses engineered cells to produce three different biologic therapies simultaneously—an anti-HIV agent, a GLP-1 peptide, and a hormone to regulate metabolism—over a month. The living pharmacy, which is about the size of a USB drive, could potentially be used to deliver any biologic drug that can be produced by the machinery of a cell, say the researchers (Device 2026, DOI: 10.1016/j.device.2026.101106).

The device is called a hybrid oxygenation bioelectronics system for implanted therapy (HOBIT). It contains a cell chamber with a high density of engineered cells in an alginate hydrogel, a small silicon chip with modified electrodes and an electrocatalyst for the oxygen-producing mechanism, and a printed circuit board with a battery to power the whole thing.

A challenge in designing the device was providing the medicine-making cells with oxygen. “Cells at low density are generally fine, but if you want cells that survive a long time at high densities, you need to supply them with supplemental oxygen,” says Jonathan Rivnay, a biomedical engineer at Northwestern, who is one of the three principal investigators of the study.

For this, the team used a previously developed electrocatalytic on-site oxygenator (ecO₂) that Rivnay describes as “basically water-splitting in a complex environment.” The ecO₂ uses a biocompatible sputtered iridium oxide film as the anode and platinum as the cathode. Between 1.6 and 1.9 V, the oxygenator selectively produces oxygen without also generating significant amounts of other, harmful by-products. The voltage can be remotely controlled via Bluetooth from a MacOS or iOS device.

The researchers tested their device by implanting versions with and without the ecO₂ under the skin of rats and monitoring their drug levels for a month. With oxygen-producing implants, all three drugs showed sustained levels in the bloodstream for the whole month. Without the ecO₂, the biologics had a shorter shelf life. When the researchers removed the implants after 31 days, the devices with the oxygenator still had about 65% of cells still viable, while the controls had 20%.

Since the publication of the paper, Rivnay says the team has done studies going up to 60 and 90 days in rats, as well as monkeys. For future iterations of this living pharmacy concept, he says, the researchers would like to be able to trigger the production of different drugs at specific times or in specific doses using external cues like light or electricity.