Breaking Down the Science in “The Human Trial”


If you watched “The Human Trial” and felt intrigued by the experimental treatment that drove it, you weren’t the only one. Here’s a breakdown of the science that was at the film’s center.

What is regenerative medicine?

Regenerative medicine describes drug therapies focused on helping the body regain organ or tissue function for conditions your body can’t heal from on its own.

Type 1 diabetes is an autoimmune condition that causes the body’s immune system to attack islet cells in the pancreas. Various regenerative treatment techniques have been trialed over time to improve the lives of people living with diabetes and attempt to cure it but none have yet triumphed in this quest. It’s possible that ViaCyte is closer than ever, as explained in “The Human Trial.”

ViaCyte is creating beta cell replacement therapies—meaning the cells have been engineered to act like the pancreatic islet cells, which contain insulin-producing beta cells. ViaCyte’s cells used for treatment are developed from stem cells.

What is beta cell replacement therapy?

Beta cell replacement focuses on introducing new healthy beta cells via a whole pancreas or pancreatic islet transplant.

ViaCyte’s stem-cell-derived cell treatment explored in “The Human Trial” is a form of beta cell replacement therapy.

When a person develops type 1 diabetes (T1D), beta cell function declines over the course of weeks or months—and sometimes longer— and they need insulin therapy to help their body use glucose. 

ViaCyte has designed cells that, when implanted into the body, mature into human pancreatic islet cells. The goal of these implanted cells is to make and release insulin on their own. 

Because the immune system of someone with T1D is already primed to attack beta cells, ViaCyte’s cells are encapsulated in a protective, permeable pod, which allows blood vessels to grow towards the cells while shielding them from being attacked. 

How is cell therapy different than insulin therapy?

Insulin has been available for nearly 100 years! It was first extracted from animal pancreases. Eventually, human insulin was able to be replicated synthetically. 

The human body is seriously complex: The pancreas produces a host of incredibly smart cells that respond to your body’s needs by regulating how much insulin and glucagon your body needs.

Your body uses insulin to convert glucose in your blood to energy your cells can use to power your body. When your blood sugar is very low, your pancreas releases glucagon, which tells your muscles to release stored glucose.

This is how your body regulates blood sugar.

Insulin therapy

Insulin therapy is a life-sustaining tool for treating insulin-dependent forms of diabetes.

Today, there are several types of insulin available: rapid-acting, short-acting, intermediate-acting, long-acting, ultra-long-acting,and inhaled insulin. They are categorized by how quickly they begin to work in the bloodstream and also how long their effects last. 

Using a combination of these drugs can help people with type 1 diabetes and people with other insulin-dependent forms of diabetes keep their blood sugar levels steady throughout the day. 

For many people, insulins within the same category (rapid-acting, etc.) can be interchangeable, but this is not true for all insulins. Different people respond differently to different drugs, but it’s not a perfect substitute for your body’s ability to produce its own insulin. 

If your blood sugar is high or low, your body isn’t able to correct on its own if you live with diabetes. This is why people with T1D need to monitor their blood sugar levels around the clock.

While the variety of insulin available makes it easier for people to manage their diabetes to suit their unique needs, it isn’t a cure. 

Who will benefit from ViaCyte’s therapies?

ViaCyte has multiple beta cell replacement therapies in the works. 

The PEC-Direct trial featured in the film focuses on implanting ViaCyte’s PEC-01 cells in patients with T1D who are considered at high risk for complications like coma or death. High-risk patients may not experience symptoms when their blood sugar gets dangerously low (also known as hypoglycemia unawareness), experience frequent highs and lows or have recurring, severe hypoglycemic episodes. 

Many of these patients are also eligible for cadaver islet transplants. However, cadaver islet cells are in short supply. PEC-01 cells, which can be produced in a lab in potentially unlimited quantities, provide a potential solution to this serious supply issue. This treatment still requires the use of immunosuppressive drugs.

ViaCyte is conducting another trial using the same PEC-01 cells called PEC-Encap, which would deliver the cells from an encapsulated device and would not require the use of immunosuppressants. The positive data reported from the PEC-Direct trial is good news for PEC-Encap as well, which could become available for all people with T1D.

ViaCyte has a third product in development, PEC-QT, that builds on the two ongoing trials and works to evade the body’s immune system. ViaCyte says this product is designed for all people with T1D as well as insulin-dependent type 2 diabetes (T2D). 

Haven’t watched the film? Check out the trailer here.

WRITTEN BY Julia Sclafani, POSTED 06/24/22, UPDATED 12/19/22

Julia Sclafani is a writer, editor and multimedia producer whose work on human rights and public health topics lead her to Beyond Type 1. She received a bachelor’s degree from Columbia University and a master’s degree from the Newmark Graduate School of Journalism at the City University of New York. An award-winning journalist, Julia cut her teeth at her hometown newspaper. You can find her past work in print, on the radio and across the web.