By Michael Le Page
It’s good news for anyone with a fear of needles. Pills containing miniature hypodermics that can painlessly inject drugs into the lining of the stomach have shown promise in initial tests in pigs.
Each pill capsule contains a number of tiny injectors. Inside each injector is a needle with a tip mostly made of a dried drug, such as insulin. The shape of these injectors – rounded with a flat bottom – was inspired by the leopard tortoise, and means they self-right within around a tenth of a second after landing of the floor of the stomach, ensuring the needle points downwards.
At the base of the needle is a compressed spring held in place by sugar. When the sugar dissolves in the stomach, the needle is fired down and the tip goes a millimetre or so deep into the stomach lining, where the drug is released and enters the bloodstream.
The stomach wall is 4 to 6 millimetres thick, so the needles should never penetrate all the way through. The stomach lining has no receptors for sharp pain and heals very quickly.
In tests, pigs were given the injectors directly, rather than within a pill capsule. The injectors succesfully delivered insulin to the blood of these animals. The pigs showed no signs of pain and their stomachs looked normal when they were examined by endoscope a week after they were given the pill.
However, the test results indicated that the pills only work when the stomach is empty, so the pills probably cannot be taken after eating. “First thing in the morning would probably be best,” says Giovanni Traverso at Harvard University, part of the team who conducted the study.
In principle, this method could be used to deliver any treatment that requires injection, says Lars Iversen of Novo Nordisk in Denmark, the company working with university researchers to develop the device.
That could make a huge difference to the one in 10 people with a fear of needles. People with diabetes who fear needles are more likely to suffer complications and die early.
What’s more, a growing proportion of new drugs consist of large molecules that have to injected. If patients could take them at home without having to be trained in how to inject themselves, it would greatly reduce treatment costs.
“Finding a way that would allow people with diabetes to take insulin orally could be a real benefit for millions, so it’s exciting to see research in this area moving forward,” says Faye Riley of charity Diabetes UK. “But this particular research is at a very early stage, and we don’t yet know if this device would be safe or effective for people with diabetes.”
Journal reference: Science, DOI: 10.1126/science.aau2277
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