The development of subcutaneous formulations of biologics is much more convenient for patients, allowing them to self-administer treatment, reducing the need to attend hospital appointments.
However, it is difficult to inject many of these formulations using commercial syringes and needles due to the high viscosity of the solutions.
Now researchers at the Massachusetts Institute of Technology (MIT) engineering department have developed a simple, low-cost device which makes injections much easier. Although subcutaneous injection formulations for biologics are already available, these often employ jet injectors that literally ‘shoot’ the drug through the skin without a needle, but such devices are expensive and can be contaminated from backsplash. Alternatives such as encapsulating drugs prior to injection can clog the needle and EpiPen type syringes are expensive.
The new system involves a syringe with two barrels, one inside the other. The inner barrel delivers the drug whereas the outer barrel provides a thin layer of lubricant that coats the drug as it enters the needle. Because the lubricant passes more easily through the needle, the drug solution experiences less shear stress. In fact, the researchers found that there was a seven-fold reduction in the force required to inject the drug. They also commented on the potential value of the technology for 3D bioprinting of tissues and administration of cell therapies, since in both cases, the treatment can be destroyed by shear damage.
Jayaprakash V et al. Enhancing the injectability of high concentration drug formulations using core annular flows. Adv Healthc Mater 2020; 24 August https://doi.org/10.1002/adhm.202001022