Vertex’s clinical trials of lab-grown islet cells

Beta cells are the insulin-producing cells destroyed by the immune system in type 1 diabetes. They are located in the pancreas within clusters of cells called islets. Scientists around world, many funded by Breakthrough T1D UK, are growing beta cells and islets in their labs. Vertex Pharmaceuticals is now giving these lab-grown islet cells to people with type 1 in clinical trials.

Clinical trial of lab-grown islet cells

Vertex is running a clinical trial in which people with type 1 receive a dose of VX-880, an investigational therapy that contains lab-grown islet cells. These islet cells are grown from human pluripotent stem cells, a type of cell that can develop into almost any other cell type. Using specific signalling molecules, the stem cells are instructed to develop into islet cells. Each patient will receive a standardised dose of islet cells via a plastic tube into a vein that goes to the liver. They also need to take immunosuppressant drugs to avoid the immune system destroying the new islet cells. After receiving VX-880, patients will be monitored for up to 5 years.

Who can take part in the clinical trial with VX-880?

The participants are all people with type 1 who experience severe hypos and hypoglycaemia unawareness. Participants must also be either blood type A or AB. As the treatment develops, the researchers hope to grow islet cells that are suitable for people of all blood types.

There will be 17 participants in total in the study – seven in the initial two stages of the trial, with a further 10 now being recruited for the final stage. There are nine trial sites throughout the US, and eight across Canada, Norway, Switzerland and the Netherlands.

Find out if you’re eligible to take part in the clinical trial with VX-880.

Participants free from taking insulin

Vertex presented the latest data from the clinical trial with VX-880 at the American Diabetes Association’s 2023 conference. Six people with type 1, who couldn’t make any of their own insulin, started the first phase of the trial. One person dropped out of the study after receiving their second dose of islet cells. Participants don’t need to explain why they withdraw their consent to participate, but the reason wasn’t because of side effects.

After receiving the infusion of lab-grown islet cells, all six patients showed signs of being able to make and release insulin again. All the participants needed to take less insulin than before the study, with some even able to stop giving themselves insulin completely. The patients also had better blood glucose control (measured by HbA1c) and improved time in range (measured by continuous glucose monitoring). Participants followed for more than ninety days after the start of treatment no longer experienced any severe hypos.

Is the islet cell treatment safe?

Part of the first stages of this clinical trial is to measure safety. This is why so few participants are involved and why they are being so closely monitored. So far, the trial has not led to serious adverse effects. The most common symptoms were dehydration, diarrhoea, low magnesium levels and rashes. Immunosuppressant drugs have the potential to cause anaemia, reduced kidney function and increased risk of infections. This is because immunosuppressants suppress the beneficial parts of the immune system as well as the part that attacks beta cells in type 1.

Encapsulated islet cells

Vertex is running another clinical trial using these same islet cells enclosed in a protective casing, a technique called encapsulation. In this trial, those participating don’t need to take immunosuppressant drugs because the case is designed to protect the islet cells from immune attack.

The trial is with the investigational therapy called VX-264 and is a first-in-human study, which means we have a lot to learn about how safe and effective the treatment will be for humans. The study is open to people with type 1, but due to the anticipated safety profile, they can’t accept people who experience severe hypos as they are particularly vulnerable. As the scientists learn more about how safe this treatment is, they hope to extend the trial to a wider population of people with type 1.

The first person in this trial has now been given a dose of the encapsulated lab-grown islet cells. This global trial is running in the US, Canada and the Netherlands, with Vertex planning to expand to additional sites. Find out if you’re eligible to take part in the clinical trial with VX-264.

How is Breakthrough T1D UK involved in this research?

For decades we have been funding stem cell research with the goal of replacing the insulin-producing cells lost in type 1 with lab-grown versions. For example, we’re currently funding Dr Fiona Docherty to grow beta cells in her lab at the University of Birmingham.

A key Breakthrough T1D UK-funded researcher in this area is Professor Doug Melton. Doug founded a company called Semma, named after his kids Sam and Emma, who both developed type 1 as children. We invested in Semma through the T1D Fund. When Vertex bought Semma, Doug started working at Vertex and his lab-grown islet cells are the cells being used in both clinical trials.

Genetically edited islet cells

In July 2022, Vertex acquired another pharmaceutical company called ViaCyte. ViaCyte had been genetically engineering lab-grown islet cells to hide from the immune system. These cells are called hypoimmune and, like encapsulation, avoid the need for immunosuppressant drugs. The first trial in humans is also underway and further data will guide next steps.

Type 1 Diabetes Cell Manufacturing Facility

Vertex have partnered with a company called Lonza to open a Type 1 Diabetes Cell Manufacturing Facility. The Facility is being built to support the high manufacturing requirements of large-scale clinical trials of lab-grown islet cells. Vertex and Lonza also plan for the Facility to produce the cells as a commercially available product once testing is complete. Construction of the enormous site will begin in Portsmouth, New Hampshire in the US later in 2023.

This multi-million-dollar investment is important because it means that Vertex has the capacity to produce islet cells on a huge scale. If results from their clinical trials continue to be positive, they will be able to expand their clinical trials to more countries with many more people.