The trouble is that hypodermic needles, and injections generally, are necessary for a variety of medical procedures, meaning patient fears must simply be confronted and overcome. And, as difficult as this can be for adults, young children in particular face a barrage of vaccinations in early life that all need to be administered via a needle.
The challenge this month is to come up with an effective alternative for administering drugs and vaccines, which avoids needles altogether. While hypodermic needles have proven extremely effective, there are many shortcomings alongside patient fear.
Drugs administered using needles are in a liquid form, which means their temperature needs to be carefully controlled in a fridge or chiller. For more remote parts of the world where electricity is not available, this creates a significant challenge.
The other obvious challenge is that any procedure using a needle requires a professional. Any solution to the challenge should not only make vaccines easy to administer, but enable them to be self-administered by patients, offering the opportunity to take vaccines in to more remote areas to immunise the population.
Of course, any solution must also be as good as needles, if not better. For this challenge also assume that the drug companies can supply powder, liquid or even vapour drugs – so don’t concern yourself with the pharmaceutical side of things.
We have a solution in mind that we will reveal next month. If you have any ideas either email them to the editor (firstname.lastname@example.org) or leave your idea below as a comment.
The solution to last month’s challenge to come up with an effective alternative to the needle comes from recent research and proof of concept hailing from the US university, UC Berkeley.
It has developed a pill-sized capsule that releases a jet of vaccine molecules to immune cells in the mouth. The technology known as MucoJet is a 15 x 7mm cylindrical, two-compartment plastic device.
While it looks distinctly like a cyanide capsule, the solid components are 3D printed from an inexpensive biocompatible and water-resistant plastic resin. The exterior compartment holds 250ml water with the interior composed of two reservoirs separated by a porous plastic membrane and a movable piston.
One interior compartment is a vaccine reservoir containing a 100ml chamber of vaccine solution with a piston at one end and a sealed 200µm diameter delivery nozzle at the other end. The other interior compartment is the propellant reservoir, which contains a dry chemical propellant and is separated from the vaccine reservoir at one end by the built-in porous membrane and movable piston and is sealed at the other end from the exterior compartment with a dissolvable membrane.
To administer the MucoJet, a patient clicks together the interior and exterior compartments. The membrane dissolves, water contacts the chemical propellant and the ensuing chemical reaction generates carbon dioxide gas. The gas increases the pressure in the propellant chamber, causing the piston to move.
The free-moving piston ensures uniform movement of the ejected drug and blocks the exit of fizz from the carbon dioxide through the nozzle. When the pressure in the propellant chamber is high enough, the force on the piston breaks the nozzle seal of the vaccine reservoir. The vaccine solution is then ejected from the MucoJet nozzle, penetrates the mucosal layer of the buccal tissue, and delivers the vaccine to underlying vaccine targets, called antigen-presenting cells.