What are beta cell therapies, and do they offer hope for a cure for type 1 diabetes?

Clinical trials in beta cell replacement are creating a buzz among the diabetes community. We explain what beta cell therapies are, how close they could be to becoming a potential treatment option, and how Grand Challenge research is helping bring them closer to the reality.  

In type 1 diabetes, the immune system attacks the beta cells in the pancreas, which make insulin. Insulin is essential for regulating our blood sugar levels. So people with type 1 have to check blood sugar and take insulin multiple times a day, every day, to stay alive. 

For many people, the advances in diabetes technologies mean that some of this constant checking and dosing can now be done automatically by continuous glucose monitoring and hybrid closed loop systems. However, even the latest tech cannot get close to mimicking the body’s finely tuned system for keeping glucose in check.  

One of the most promising routes to a cure for type 1 diabetes is to seek ways to replace the lost beta cells and restore insulin production. We know it can work – the first successful human transplants of beta cells taken from a donor happened as far back as 1990.  

The parts of the pancreas that contain beta cells are known as islets. In 2008, the UK launched an islet transplant programme for people with type 1 diabetes who experience frequent life-threatening episodes of low blood sugars (severe hypoglycaemia, or ‘hypos’) but have no awareness of the warning signs. It was an exciting advance, offering the hope of freedom from insulin therapy for some. 

Islet transplants are limited

While islet transplants are pretty effective at giving people more stable blood sugar levels and cutting episodes of dangerous lows, there are several reasons why they’re not widely suitable as a treatment for type 1:  

• Data suggests that an average of 3 donor pancreases are needed for 1 successful transplant. Donor organs are sourced from deceased individuals and – like most transplant programmes – the demand severely outweighs the supply of usable tissue.    

• Transplants from a donor may be rejected by the body, so recipients must take lifelong medication to suppress their immune system (immunosuppressants). This leaves people compromised – at greater risk of certain cancers and severe infections.  

• Despite immunosuppression, transplanted islets often fail to survive in the long term because they can’t get the oxygen and nutrients they need.  

• While they can allow some people to temporarily stop insulin therapy, this is rarely permanent. Over time, most people will need insulin again, although usually at lower doses. 

Fewer than 350 islet cell transplants took place in the UK between 2008 and 2022. There’s an urgent need to find effective and sustainable alternative approaches to beta cell replacement that can be accessed by many more people with type 1. That’s why beta cell replacement is one of the three major research themes of the Type 1 Diabetes Grand Challenge. 

Exciting trials underway

Some of the most talked-about research happening in type 1 diabetes right now are clinical trials in beta cell replacement.  

One trial, led by a company called Vertex, is testing transplants of beta cells grown in the lab. The results have been really promising, with some participants no longer needing insulin. However, they still need powerful immunosuppressants to prevent rejection. The treatment is now in the final phase of testing, and if all goes well, Vertex plans to seek global approval in 2026. It’s likely this would initially only be for people who experience frequent severe hypos and have no hypo awareness.   

In October 2024, Chinese researchers reported positive results using beta cells grown from a patient’s own stem cells. It’s very early days – they only tested it in one person – but this approach has potential to overcome the rejection problem because the transplanted cells would be recognised as ‘self’.  

Another first-in-human study was reported by Sana Biotechnology at the start of 2025. They used donor beta cells but gene-edited them to become invisible to the immune system. After four weeks the transplanted cells had avoided immune attack and were producing insulin.  

The bigger picture

Type 1 diabetes is complex and we’re unlikely to land on a one-size-fits-all cure. So, while the current trials are hotly anticipated, they’re only one part of the story. And that’s why the Type 1 Diabetes Grand Challenge is funding over £16 million into 10 research projects looking at building better beta cells for transplantation, protecting beta cells during and after transplantation and regrowing beta cells in people with type 1 diabetes.

Nearly two decades after the islet transplant programme launched in the UK, we’re getting closer to better beta cell replacement therapies. And the Grand Challenge is helping to push the pace of progress so that more people can be released from the daily burden and dangerous complications of type 1 diabetes.