What are the benefits and risks of human stem cell treatment compared with no active treatment, supportive treatment, or placebo, in people with decompensated cirrhosis?

Key messages

There is uncertainty in:

• whether human stem cells (i.e. special types of cells that can renew themselves and develop into many different cell types in the body) are beneficial in reducing death in people with decompensated cirrhosis (i.e. an advanced liver disease) compared with no active treatment, supportive treatment, or placebo (dummy injection);

• whether human stem cells may decrease or increase serious unwanted effects;

• whether human stem cells may improve the health-related quality of life (well-being);

• whether human stem cells may reduce complications;

• whether human stem cells may increase non-serious unwanted effects or may improve liver function tests (blood tests that measure substances in the liver).

What are decompensated cirrhosis and human stem cells?

In cirrhosis, normal liver cells are replaced by scar tissue. Decompensated cirrhosis is an advanced stage of cirrhosis, causing the liver to be incapable of functioning. People with decompensated cirrhosis usually present with yellow discolouration of the eyes, skin, and urine, gas or fluid accumulation in the belly, confusion, vomiting of blood, or weakened kidney function. Decompensated cirrhosis requires liver transplantation, which is not free of harms, and donors are not always available. Human stem cells may be an alternative method for people with progressive deterioration of liver function because they may promote liver cell regeneration and recovery.

What did we want to find out?

We wanted to find out if human stem cells, regardless of focus on adults, or sex, type of stem cell, route of injection, or administered dose, are better than dummy injections (placebo), conventional or regular treatments, no treatment, or supportive treatment (that is, control interventions) to reduce death and serious (life-threatening) unwanted events and improve well-being. We also wanted to find out if human stem cells were associated with complications, non-serious unwanted effects, or changes in liver function.

What did we do?

We searched for studies that compared human stem cell treatment with a control group receiving dummy injection, regular treatment, no treatment, or supportive treatment.

What did we find?

We found 12 studies that included 823 adults with decompensated cirrhosis. Studies investigated six groups of human stem cells (bone marrow-derived mesenchymal cells, mononuclear cells, umbilical cord stem cells, autologous cells, CD34/133+, and CD133+ cells).

Stem cell transplantation was performed through the hepatic artery in six studies, portal vein in two studies, upper extremity veins in two other studies, and intravenous route in one study. One study did not provide information about the route of cell transplantation. The smallest study included 27 people, and the largest study included 219 people. University, industry, national, or provisional research grants funded these studies. All 12 studies had problems with design and methods.

The evidence is very uncertain about the effect of the studied human stem cells compared with any of the above-mentioned control interventions on death; 41 of 308 people (13.3%) compared with 78 of 269 people (29%) died after monitoring for 3 months to 75 months (seven studies).

The evidence is very uncertain about the effect of the studied stem cells compared with any of the above control interventions on serious unwanted effects. Seventy-four of 366 people (20.2%) compared with 108 of 312 people (34.6%) experienced serious unwanted effects after monitoring for one month to one year (eight studies).

The evidence is very uncertain about the effect of the studied stem cells compared with any of the above control interventions on the well-being of people after monitoring for one and six months (two studies).

The evidence is very uncertain about the effect of the studied stem cells compared with any of the above control interventions on the development of complications; 20 of 154 people (13 %) compared with 29 of 150 people (19.3 %) experienced one or more complications after monitoring from three months to one year (four studies).

The evidence is very uncertain about the effect of the studied stem cells compared with any of the above control interventions on non-serious unwanted effects; 26 of 226 people (11.5 %) compared with 1 of 211 people (0.5 %) experienced non-serious unwanted effects after monitoring from 1 month to 75 months (five studies).

The evidence is very uncertain about the effect of the studied stem cells compared with any of the above control interventions on liver function tests after monitoring from three months to one year.

We identified 12 ongoing studies (where results have not yet been reported).

What are the limitations of the evidence?

Insufficient study methods could exaggerate or underestimate the benefits and unwanted effects of human stem cells. We still lack evidence on the effect of human stem cells compared with dummy injection, no treatment, or supportive treatment on death, well-being, serious and non-serious unwanted effects, and the development of complications.

How up-to-date is this evidence?

The evidence is up-to-date as of 4 October 2024.