Dr. Hyowon “Hugh” Lee, an assistant professor of biomedical engineering and his team at Purdue University have been developing an interesting implantable drug delivery system. Unlike traditional pumps, this device is meant as a one-time injector for life-saving drugs such as naloxone (opioid antidote) or epinephrine (treatment for anaphylactic reaction).
The implantable “A2D2” capsule contains the drug in a capsule that is sealed with a phase-change material. When heated, this material melts and allows the capsule’s payload to be delivered to the body.
Activation is accomplished through an external controller that inductively heats a stainless steel plug within the A2D2. The external controller is meant to have the means to detect an opioid overdose by monitoring the patient’s ECG and respiration, thus allowing for fully-automatic delivery of the life-saving antidote.
According to the paper “Simple minimally-invasive automatic antidote delivery device (A2D2) towards closed-loop reversal of opioid overdose,” the device can release 1.9 mg of powdered naloxone drug within 60 s and up to 8.8 mg in 600 s.
The device is just in its feasibility stage. The paper shows that the A2D2 prototype leaked 1.75% of its drug payload over the course of 1000 h of simulated implantation. As such, the researchers acknowledge that further development and testing of the device is needed to verify its long-term stability in-vivo. In addition, further research is required in the development of a reliable controller capable of detecting an opioid overdose and automatically releasing the drug.