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Biological and Immune Suppressant Therapies Explained! How they work, risks, etc...

As an IBD sufferer, I have been on many treatments over the last 15 years, I take them, often without fully understanding what they are and what they can do for me. Now facing a new biological therapy I had many questions such as; why is is different? how does it work? what are the risks of having an impaired immune system?

I started researching all the therapies I know and am now sharing my findings with you, Hopefully this will also allow carers and loved ones the understanding of the risks we face so they can help us to stay healthy, as well as eliminate avoidable problems.

Your immune system, which normally responds to foreign threats, microorganisms, and intestinal bacteria, is out of balance and mounts inflammatory attacks against your own body. It is believed that substances in the intestines are mistaken for invading substances.

The immune system causes temporary inflammation to combat these substances and lessens the response as you regain your health.

In IBD, the inflammation can persist long after the time when the immune system should have completed its response. This in effect means the body starts attacking itself, thus causing a flare up of disease.

For the majority of IBD sufferers a flare up is treated successfully with course of medications such as corticosteroids (often Prednisolone) and 5-ASA Such as Mesalazine.

All the following have an impact on the bodies immune system and can leave patients vulnerable to illness, disease, infection and in some cases, serious development of otherwise ‘normal’ ailments.

So what are they and how do they work?

Corticosteroids (Commonly used Prednisolone)

Corticosteroids are anti-inflammatories, meaning they decrease levels of inflammation in the body. They are man-made versions of the hormone cortisol which is created by the human body in the adrenal glands. Taking corticosteroids causes the body to slow down production of, or stop making, cortisol. The body then receives the cortisol it needs from the corticosteroids.


5-ASA drugs (such as Mesalazine/Olsalazine ) are bowel specific anti-inflammatory drugs. They belong to a group of medicines that act on the inflamed lining of the gut (intestine) to prevent the formation of substances that cause inflammation. They have less systemic absorption and fewer adverse effects than many other medications mentioned.

IBD is also treated with various other oral immune suppressant drugs such as Azathioprine.


In autoimmune diseases, Azathioprine reduces the immune system attack on normal tissues and so reduces the severity of the symptoms, and in many cases halts the progress of the disease. However, the immune system relies on the action of different types of white blood cells that are produced in the bone marrow and lymph glands. Azathioprine works by decreasing the production of these white blood cells.

Unfortunately, white blood cells also fight invading germs, so during treatment the body becomes more susceptible to infections. It can cause anaemia and reduced production of platelets can cause problems with blood clotting.

I was on all the above at various times over the last 15 years, However, Azathioprine, which did manage my symptoms well for 11 years, was thought to raise the risk of cancers with prolonged use, therefore I was taken off it whilst in remission.

For many IBD suffers, as I found first hand, over time, these are no longer a viable option due to many reasons such as; drug resistance, intolerable side effects, long term risks, escalation of symptoms and worsening of the disease despite treatment.

At this stage, I, and millions of others, are left facing surgery and /or further treatment options such as immunotherapy in the form of biological drugs.

Immunotherapy and Biologics

Immunotherapy is the treatment of disease by activating or suppressing the immune system often known for its use in treating Cancer, However, for IBD, the immune system is suppressed to stop the body attacking itself.

Biological Immune suppressant options vary depending on symptoms, licencing and effectiveness for each symptom. Many are aimed predominantly at Crohns as they impact the complete system and other symptomatic problems such as arthritis, joint pain etc. Whereas some treatments are colon or gut specific, therefore may be more likely to be tried initially for ulcerative colitis, and other forms of IBD that are more specifically affecting the large bowel.

Personally, I have had 2 forms of biological immune suppressant therapies, Infliximab and Humria.

Infliximab (Remicade)

Infliximab inhibits a chemical called tumor necrosis factor (TNF)-alpha. Your body naturally produces TNF-alpha as part of its immune response to help fight infections by temporarily causing inflammation in affected areas. Over-production of this protein is thought to be partly responsible for the type of chronic (ongoing) inflammation found in IBD. Infliximab binds to TNF-alpha, helping to prevent inflammation and relieve symptoms

It is administered by very slow intravenous injection, in hospital. Interestingly, Infliximab is made from human & mouse monoclonal antibodies.


Humira (adalimumab)

Similar to Infliximab, Humira binds to TNFα and blocks its inflammatory effect. This reduces pain and inflammation in people with autoimmune diseases. However, Humira is made from human monoclonal antibodies.

Humira is taken at home, using a syringe or pen device that already contains the medication. It cannot be taken by mouth because the digestive system would destroy the active ingredient.

In my experience the injections can cause local irritation and sting when done but are simple to administer. ( I have since been informed that apparently it is the citric acid in the formula that causes the irritation, there is a new formula available in the UK and some other countries that do not contain this and therefore there is no sting).


Complication with Anti TNF Blockers

Complications may arise with the use of biologics. They can include, but are not limited to; serious life-threatening infections, viral, bacterial or fungal, which flare up as a result of the suppression of the natural inflammatory reaction to intruders. Worsening of congestive heart failure. Hepatitis and Optic neuritis.

For children and adults taking TNF blockers, the chance of getting lymphoma or other cancers may increase.

For these reasons’ patients must take care to reduce exposure to illness where they can and understand the common ailments such as colds, flu and coughs can be far more severe. They are at severe risk of complications from exposure to viruses.

So, what happens when TNF Blockers no longer work, or you don’t respond to therapy?


Vedolizumab, another biological drug, works in a different way to the anti-TNF drugs, because it is a ‘gut-selective integrin blocker’. White blood cells are made by the immune system to fight against infection. However, in CD and UC, overproduction of white blood cells leads to inflammation – Vedolizumab works by stopping the white blood cells from entering the lining of the gut. This means that the drug only targets the gut, rather than the whole of the body like the anti-TNF drugs do and may cause fewer side effects.


Vedolizumab = Gut Specific

I was offered Vedolizumab recently to treat inflammation in the rectal cuff and JPouch, known as Cuffitis and Pouchitis. I chose not to start it as I am suffering more symptoms that are not just gut specific, including enthesitis, therefor I wanted a wider spread treatment. I am due to start a newly licenced biologic for Crohns known as Stelara.

STELARA® (Ustekinumab)

There are many different naturally occurring proteins in the body that contribute to inflammation. Patients with Crohn's disease are found to have elevated levels of two of these proteins, IL-12 and IL-23.

Stelara is the only FDA-approved medicine that targets IL-12 and IL-23, which are thought to be associated with gastrointestinal inflammation in Crohn's disease.

Treatment starts with a one-time intravenous (IV) infusion that provides the amount of medication based on your body weight and is administered in a hospital or clinic by medical professionals.

After this you’ll self-administer maintenance injections given under the skin every 8 weeks.


Stelara affects your immune system and can increase your chance of having serious side effects. It may lower your ability to fight infections and may increase your risk of infections.

While taking Stelara some people have reported serious infections, which may require hospitalisation, including tuberculosis (TB), and infections caused by bacteria, fungi, or viruses.

Due to the potential decrease the in activity of your immune system, it may increase your risk for certain types of cancer.

Stelara has been linked to a risk of ‘Reversible posterior leukoencephalopathy syndrome (RPLS)’

RPLS is a rare condition that affects the brain and can cause death. The cause of RPLS is not known. If RPLS is found early and treated, most people recover.

All medications can have common side effects, details of which are available via the references I have shared.

After discussion with my Gastroenterologist and Rheumatologist Consultants I am due to start Stelara on Dec 2018 and will share my experience in the future publications.

The information I have shared has come from my extensive research and personal knowledge gained from experience, however I am not a medical professional, therefore you should always consult your medical practitioner before considering any of the above.

This blog serves to provide a central place to share information gathered and help sufferers and their carers live with the treatments they need to survive.

Any medication that lowers the immune system opens us up to other risks, but we can educate to protect ourselves!

Keep fighting and stay strong!

Andrea x


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