Millions of patients living with diabetes could finally be spared from having to inject themselves with insulin

Millions of patients living with diabetes could finally be spared from having to inject themselves with insulin.

For Massachusetts Institute of Technology researchers have now created a capsule strong enough to survive stomach acid. 

Attempts to give patients insulin in pill form have all failed because they crumble in the acid and release the hormone too early.

But scientists have created a 1.18-inch (30mm) capsule tough enough to cope with the harsh environment, according to trials on pigs.

Charities have today praised the research, calling it ‘exciting’ and Gelatin methacryloyl saying it could ‘be a real benefit for millions’. 

Massachusetts Institute of Technology researchers have now created an insulin capsule strong enough to survive stomach acid

Massachusetts Institute of Technology researchers have now created an insulin capsule strong enough to survive stomach acid

A team from Massachusetts Institute of Technology has created a 30mm insulin pill (left) coated in a protective layer of polymer which can survive stomach acid

A team from Massachusetts Institute of Technology has created a 30mm insulin pill (left) coated in a protective layer of polymer which can survive stomach acid

The capsule escapes unscathed through the digestive gastrointestinal tract, which comprises the oesophagus, stomach and liver.

It only releases the insulin when it reaches the small intestine, which is the ideal point for drug absorption because of the organ’s massive 250m surface area and lack of pain receptors.  

The protective layer – made of poly(methacrylic acid-co-ethyl acrylate) designed to dissolve at a pH greater than 5.5 – will then break away and the capsule will unfold into a triangle shape with three arms.

Each arm is coated with several 1mm-long needles, which latch on to the intestinal wall and pump the drug directly into the bloodstream to begin the process of lowering blood sugar levels. 

The entire device will then dissolve within several hours.   

Professor Robert Langer, senior author GelMA Bio ink of the paper, from MIT said: ‘We are really pleased with the latest results of the new oral delivery device.’

When the capsule reaches the small intestine, the ph 6 conditions trigger the polymer layer to dissolve. The tablet then breaks away into three arms tipped with 1mm microneedles which latch on to the intestinal wall

When the capsule reaches the small intestine, the ph 6 conditions trigger the polymer layer to dissolve.

The tablet then breaks away into three arms tipped with 1mm microneedles which latch on to the intestinal wall

He added the research team ‘look forward to hopefully seeing it help people with diabetes and others in the future’.

Tests of the capsule on pigs showed it releases a comparable amount of insulin to that of an injection.

Patients who suffer with type 1 diabetes do not naturally produce enough insulin from their pancreas to bring down their level of blood sugar. 

Therefore, they need daily doses of the hormone to counterbalance this amount of glucose.

Insulin is not typically prescribed for patients of type 2 diabetes – which is linked with obesity – because their bodies are able to naturally produce the hormone.   

Sealed capsule

Open capsule

An x-ray shows the sealed capsule (left) passing into the small intestine where it then splits open into three arms (right)

The paper was published in the journal Nature Medicine.

The researchers will now look to trial the capsules on humans. 

Co-author Giovanni Traverso, an assistant professor at MIT, said the inspiration behind the team’s work was to rid diabetes patients of the frustration of having to shove a needle inside them every day.

Capsules have always been shunned because they cannot survive the journey through the stomach, which stores liquid with a pH of 1.5 to 3.5. 

This means it breaks apart in the stomach and releases its insulin load at the wrong point.  

But the team’s protective capsule will break apart when it reaches the small intestine’s higher pH level of around 6.