What is ulcerative colitis? Symptoms, main causes and results of etrasimod treatment trial - explained

A recent trial of etrasimod - a treatment for Ulcerative Colitis - found that 27% of sufferers who had failed to respond to any other treatment were found to be in remission after just 12 weeks, and 32% were symptom-free after a year.

But what is ulcerative colitis and how does the etrasimod treatment work?

Here’s what you need to know.

What is ulcerative colitis?

Ulcerative colitis is a long-term condition where the colon and rectum become inflamed.

The colon is the large intestine (bowel) and the rectum is the end of the bowel where stools are stored.

Small ulcers can develop on the colon’s lining and can bleed and produce pus.

What are the symptoms of ulcerative colitis?

The severity of the symptoms varies depending on how much of the rectum and colon is inflamed and how severe the inflammation is, but for some people, the condition has a significant impact on their everyday lives.

The main symptoms of ulcerative colitis are:

• recurring diarrhoea, which may contain blood, mucus or pus
• tummy pain
• needing to empty your bowels frequently

You may also experience extreme tiredness, loss of appetite and weight loss.

What causes it?

Ulcerative colitis is thought to be an autoimmune condition, which means the immune system (the body’s defence against infection) goes wrong and attacks healthy tissue.

It’s thought that the immune system mistakes harmless bacteria inside the colon for a threat and attacks the tissues of the colon, causing it to become inflamed, but exactly what causes the immune system to behave in this way is unclear.

According to the NHS, most experts think it’s a combination of genetic and environmental factors.

When should I see a GP?

You should see a GP as soon as possible if you have symptoms of ulcerative colitis and you have not been diagnosed with the condition.

Your GP can arrange blood or stool sample tests to help determine what may be causing your symptoms and if necessary, they can refer you to hospital for further tests.

What is the treatment?

Treatment for ulcerative colitis aims to relieve symptoms during a flare-up and prevent symptoms from returning.

In most people, this is achieved by taking medicine, such as:

• aminosalicylates (ASAs)
• corticosteroids
• immunosuppressants

What is etrasimod?

Once-a-day tablet etrasimod treats the condition ulcerative colitis by binding to immune cells and preventing them from attacking healthy tissue in the lining of the gut.

A recent trial found that 27% of sufferers who had failed to respond to any other treatment were found to be in remission after just 12 weeks, and 32% were symptom-free after a year.

Dr Sami Hoque, a gastroenterologist at Barts Health NHS Trust in London who ran the UK arm of the etrasimod trial, told the Daily Mail: “When I started treating ulcerative colitis, there were very few options available, and what we did have caused severe side effects.

“The advantage of etrasimod is that it is very selective, able to target unruly inflammatory cells without affecting the immune system as a whole.

“It’s a significant addition to existing treatments for bowel disease and, unlike other therapies which involve injections, it comes as a once-daily tablet. This puts the power in the hands of patients, meaning they can avoid regular visits to hospital.”