Biological therapies are a newer type of DMARDs (disease-modifying anti-rheumatic drugs) that work by blocking the immune response that causes arthritis.
The immune system is the body’s system for stopping illness and disease. When an illness enters our body, a response from the immune system is triggered to fight it off. Arthritis is an auto-immune condition, which means the immune system cant tell the difference between healthy body tissue and harmful things such as infection, so it starts attacking normal body tissues by mistake. In certain types of arthritis, the immune system triggers the body to overproduce:
- Tumour necrosis factor (TNF), a chemical in the blood
- B-cells, a type of white blood cell
- Interleukins or ILs, a protein
TNF, B-cells and ILs all cause inflammation in the joints in people with certain types of arthritis. Biological therapies work by blocking these. So for example anti-TNFs are a group of drugs which block the production of TNF.
B-cell treatments remove B-cells from the blood and anti-IL treatments remove interleukins.
People are normally given biologic treatments because their DMARDs (such as methotrexate) are not working well. David Z described biological therapy as “the next stage on” from the DMARDs.
Some biological therapies are injected. Others are given to the person via a drip (infusion) in hospital.
The most common anti-TNF medications currently used to treat young people with arthritis are etanercept (Enbrel), infliximab and adalimumab (Humira).
Some of the people we spoke to said that they benefited lots from taking anti-TNF medication. Elizabeth said adalimumab (Humira) stopped her from “hurting all over”. Jessica’s mum described etanercept (Enbrel) as “life-changing”. She said that Jessica went from being somebody who could hardly move to somebody who could “participate in life”.
People sometimes said that their anti-TNF medication worked for a certain amount of time but then stopped working. Doctors might then try the person on a different type of anti-TNF medication.
Some of the people we talked to said that anti-TNF medication caused no side effects. Others felt like they got ill more than others. Anti-TNFs work by suppressing (or weakening) the immune system (they are ‘immunosuppressants’) so people who take it become more prone to infections.
People who experienced side effects after taking etanercept noticed a number of changes. Elly said her cuts took longer to heal. Sarah said she had a permanently sore throat and blocked nose. She said that these were “minor side effects” compared to the “full swing of arthritis”.
People also reported side effects after taking adalimumab. Catherine said that it might have given her headaches and stomach aches. Michelle said she got a red, itchy patch on her leg where she injected it.
Etanercept and adalimumab are taken as subcutaneous injections (injections just under the skin). Some people injected themselves at home. They used a syringe or a pen device. Others were injected by parents or healthcare professionals. Some people said that the syringe hurt more. Others said the pen device hurt more. Sometimes people felt no pain at all, or said that the medication stung more than the needle going in. Adalimumab sometimes stings more than etanercept. Sometimes the area which was injected became red, swollen, sore or bruised. To help prevent this people alternated which leg was injected. Sometimes people injected the skin of their stomach because it hurt less. Catherine used a bag of peas to numb where she was going to inject. Beth had pressure applied to her leg after her injection to help with the pain.
People who took adalimumab could use a ready-made syringe which contained the medication. People who took etanercept (Enbrel) had to mix the medicine and put it in a syringe themselves.
People sometimes took methotrexate with anti-TNF medication. However, some people preferred to take anti-TNF medication on its own, especially if the methotrexate gave them side effects (see DMARDs). In some cases, methotrexate has to be given with certain biologics, such as infliximab.
Adalimumab in combination with methotrexate, was shown in a recent trial (2015) to be an effective therapy in children and adolescents with JIA-associated uveitis. The trial outcomes directly led to the changes in commissioning guidelines and resulted in NHS England approving the use of adalimumab in children with uveitis that threatens their sight, and for whom other treatments have proven ineffective.
B-cell therapy and anti-IL treatments
Rituximab is the only the type of B-cell therapy available and is used for people with rheumatoid factor positive polyarthritis JIA or adults with rheumatoid arthritis (RA). Tocilizumab and anakinra are anti-IL treatments used to treat people with systemic JIA and adult RA.
Ryan was put on a tocilizumab clinical trial without taking an anti-TNF treatment first, but others were given B-cell therapy after trying anti-TNF medication and finding it did not help. Kyrun tried 6 different anti-TNFs but each one only worked for a month. He then tried tocilizumab and has been on it for a year. When Ryan was given tocilizumab he said that the number of joints affected by arthritis went down from eleven to three. He could also walk short distances again.
Lucy took anakinra and hardly noticed that she has arthritis.
Tocilizumab is taken as a drip (infusion) in hospital. Ryan was not allowed to eat for 24 hours before he had his drip. He said he was so hungry he felt sick. Kerrie said that the first time she had a drip it felt “daunting”. She was in a room with lots of people having drips. She could eat and drink as normal.
Lucy takes anakinra for her systemic JIA and injects the medication.