12 of 12 trial participants are no longer injecting insulin, thanks to new immunosuppressive drug tegoprubart

What does the new data show?

Presented by Dr. Piotr Witkowski, of the University of Chicago, the study administered insulin-producing cell transplants (islet transplants) to 12 adults with long-standing type 1 diabetes (T1D) and severe hypoglycaemia. When these islets are transplanted into people with T1D, they need to take drugs called immunosuppressants (also known as anti-rejection drugs) to prevent their immune system killing them.  

However, in the Eledon trial, instead of a more traditional immunosuppressive drug tegoprubart is used. The results so far have been incredibly promising, and the new data backs this up: 

• All 12 participants are no longer injecting insulin since their transplant approximately 10 months ago 
• Zero rejection episodes; no specific markers were found to signal transplant failure  
• Between three to five times more transplanted islets survived and took hold compared with historical controls 
• No kidney damage, nerve damage, or high blood pressure was seen, which are the common side effects of existing drugs 

A possible explanation for the higher survival rate of islets is that anti-rejection drugs can be harmful to insulin-producing cells, potentially damaging the very transplants it is intended to protect. Tegoprubart appears to avoid this issue. During the entire follow-up period after transplantation, the islets remained healthy, with no evidence of kidney damage, blood clots, or any unexpected side effects. 

What is the ‘Eledon trial’?

The Eledon trial is being widely spoken about across social media. It is run out of the University of Chicago by a company called Eledon Pharmaceuticals. It is a phase 1/2 trial testing the drug tegoprubart in people with T1D who receive transplanted islets from a donor. 

In the trial, participants receive: 

• An islet cell transplant (clusters of insulin-producing cells taken from a donor pancreas) 
• An experimental anti-rejection drug called tegoprubart to prevent the immune system from attacking the transplanted cells 

The goal is to see whether this targeted immunosuppressive drug can protect the transplanted cells without the unwanted side effects of standard anti-rejection drugs. 

What do these results mean for me?

This clinical trial represents a meaningful step in the right direction for people with T1D, but it is only one part of a larger effort. Breakthrough T1D, Eledon, and others are continuing to build on this progress. 

While tegoprubart is showing strong potential in addressing the need for broad-spectrum immunosuppression, other barriers still limit access to islet transplants. The main challenge is the limited availability of islets from deceased donors. In many cases, people with T1D require islets from multiple donors, and some may need more than one transplant over time. Expanding access will depend on securing a larger, more reliable supply of islets. 

To tackle this issue, researchers are working to develop methods for producing islets in the lab, which would remove supply issues and make these treatments more widely available to everyone with T1D. 

How has Breakthrough T1D supported this research?

The T1D Fund, A Breakthrough T1D Venture has invested in Eledon Pharmaceuticals, the company developing tegoprubart. 

The trial at the University of Chicago is funded through Breakthrough T1D with additional support from the Cure Alliance. 

You can find more information on tegoprubart and the Eledon trial on our website.