Living Pharmacy: How Implants Could Produce Drugs Inside the Body for Weeks

Revolutionary Implant Acts as a 'Living Pharmacy' Inside the Body

Having to take multiple medications on a regular basis can be a major burden. (Photo: Lisa S. / Shutterstock)

Relieving the daily struggles of chronically ill patients is the shared goal of researchers at Northwestern University, Rice University, and Carnegie Mellon University in the U.S. If their vision succeeds, cumbersome pills and injections could soon become a thing of the past—replaced instead by a kind of living pharmacy inside the body that takes over drug delivery.

The team has developed an ultra-compact bioelectronic implant and successfully tested it in animal trials, as recently reported in the journal Device. The system delivers therapeutic compounds via genetically engineered cells and, thanks to an onboard oxygen supply, operates reliably for several weeks.

The implant, named HOBIT (Hybrid Oxygenation Bioelectronics System for Implanted Therapy), is roughly the size of a USB drive. It contains genetically modified cells encapsulated in alginate, which produce three different biologic drugs: an anti-HIV antibody, a GLP-1-like peptide for treating type 2 diabetes, and leptin, a hormone that regulates appetite and metabolism. To enable exchange with the body, the implant is enclosed in a semipermeable membrane.

The real innovation, however, is its built-in oxygen factory. A battery-powered electrochemical cell extracts oxygen from water, supplying the cells directly on site with this vital resource. "This allows us to maintain much higher cell densities in a far smaller space," explained Jonathan Rivnay of Northwestern University, one of the study's authors. "The cell densities in HOBIT were about six times higher than in conventional encapsulation approaches without oxygen supply."

When implanted under the skin of rats, the living device maintained stable drug concentrations for 31 days. "Conventional medications often have widely varying half-lives, making it difficult to sustain steady concentrations when multiple therapies are involved," Rivnay noted. Here, too, the new system offers a clear advantage.

Still, the path to human application remains long—particularly because regulatory approval for this novel form of cell therapy is still uncertain. Next, the researchers plan to test their system in larger mammals and further miniaturize it. Their success will be closely watched by the project's funders: the diabetes organization Breakthrough T1D and the U.S. Department of Defense.