Needles and Antigen Delivery

As John mentioned yesterday there are a few needle ideas we have in mind.

The first is coating a solid needle with an antigen layer which will dissolve and stay in the body. We have concerns about how exactly the layer would dissolve and how long it would take. This method is currently being researched in MIT to deliver DNA vaccines with microneedles.

Another idea is to have a hollow needle with the antigen in the needle. A water soluble polymer would block the hole to prevent leakage. Once the needle is inserted into the skin, the polymer would dissolve and the antigen liquid would leak out. We would have to choose a polymer that dissolves almost instantly when it reaches extracellular matrix in the body to have fast delivery of the antigen.

Another idea is having 2 layers in the microneedle pad. A top layer that contains the microneedles and a lower layer that contains pouches with the antigens. When the top of the device is clicked, the microneedles will lower to reach and pop the pouches and then pierce the skin. How do we know the liquid in the pouch actually reaches the inside of the body?

Another is a combination of the last two ideas. Having the pouches inside a primary hollow needle that has another needle inside the primary needle. When device is pushed and reached the body, the internal needle will pop the internal pouch and the hollow needle will direct where the antigen liquid goes. The concern would be how to manufacture the needles.

We are currently discussing the designs of the needles and how the manufacturing of each will maintain the cost reasonable.