What are biologic drugs for RA?

Biologic drugs are a more recent group of medications used to treat inflammatory arthritis. This term is used because these medications are produced using biologic processes instead of being chemically synthesised, as is the case with many other medicines. They come from natural sources such as humans, animals or micro-organisms. Many are produced through a process called biotechnology and this is a more recent and rapidly developing area of human health.

Biologics using recombinant DNA have become very common in treating diseases particularly in the areas of rheumatology (for inflammatory arthritis), cancer, cardiology, skin and stomach conditions and neurology.

Anti-TNFs are a type of biologic drug that are being used to treat rheumatoid arthritis. These work by blocking the action of a protein called TNF, which is produced by white blood cells to trigger inflammation. TNF is a chemical, which is thought to play a role in the inflammation and tissue damage, which occurs in some forms of inflammatory arthritis.

Biologic drugs are not suitable for everyone. However, they can be very effective in appropriate people. They may cause side effects and this issue will be discussed by your health professional. Biologics are now playing an important role in controlling RA in people who have a severe inflammatory form of the disease and who have not responded well to other disease-modifying drugs.

Some newer biologics (which are not anti-TNFs) can target even more specific parts of the immune system and these may prove effective in people who have not responded to an anti-TNF drug.

Biologic drugs are not suited to everyone with inflammatory arthritis and doctors will only recommend them for appropriate patients. Patients are closely monitored while on these treatments.

These medications are administered to suitable arthritis patients in hospitals or special clinics by either IV infusion or injection. Self-injection at home is often possible with the necessary support and instruction.

Specific biologic drugs

Three drugs; adalimumab, etanercept and infliximab are anti-TNF drugs which are prescribed when other treatments are not effective and arthritis symptoms are not being adequately controlled. They are not prescribed to pregnant or breastfeeding

women or to people who have had certain infections, in particular cancer or TB. These drugs may be given by injection under the skin or by IV infusion.

Three other drugs; rituximab, abatacept and tocilizumab are newer biologic drugs and are given to people who do not respond to anti-TNFs. These drugs are all given by IV infusion.

Both groups of drugs have possible side effects and your doctor will discuss these with you. It is important to tell your health professional if you have experienced anything unusual while taking your treatment, as this may be a side effect.

When on these treatments you will be monitored carefully and may have blood tests and x-rays before the treatment is commenced.

Adalimumab (Humira)

This is an anti-TNF drug for people with severe rheumatoid arthritis. It is is prescribed where a person has active rheumatoid arthritis and has not responded to methotrexate and other disease modifying drugs.

It is given once every two weeks by injection. It can be given at home after instruction or it may be administered by a nurse. Its effects will start to be seen any time between two and 12 weeks.

Etanercept (Enbrel)

This is an anti-TNF drug. It is also used to treat children with juvenile idiopathic arthritis and those with psoriatic arthritis and ankylosing spondylitis. 
The conditions for use are similar to adalimumab.

Etanercept is injected under the skin once or twice a week. You will have a chest x-ray and blood tests before starting treatment and regular blood tests while you are taking the drug. The effects of treatment will be felt around 2 to 12 weeks

Infliximab (Remicade)

Infliximab is also an anti-TNF. It is given over several sessions, usually in hospital using an intravenous drip into a vein. You will have a chest x-ray and blood tests before starting treatment and regular blood tests while you are taking the drug. Effects should start to be noticed in 2-12 weeks.

Rituximab (MabThera)

This is a newer type of biologic drug for severe rheumatoid arthritis. The drug selectively targets B-cells, which are known to play a role in the progression of rheumatoid arthritis. Rituximab is suitable for people where treatment with other medications, including anti-TNFs has not been effective.

Rituximab is for use in conjunction with methotrexate. Rituximab is given in a single treatment course of two infusions two weeks apart. Each dose, which is usually given in a hospital, lasts for 6-12 months.

Abatacept (Orencia)

This also a newer drug and doesn’t need to be given with methotrexate. It works by interfering with the T-cell response, which affects the mechanism of rheumatoid arthritis. It is given by infusion in hospital. After the first dose, you received a second dose two weeks later. Then it is administered every four weeks.

Tocilizumab (RoActemra)

This a newer biologic drug and is administered by monthly infusion and may be used on its own or in combination with methotrexate. It works by blocking one of the most common chemical influencers in the rheumatoid system called IL-6. This is given by infusion in hospital every four weeks.

Side effects

These medications have possible side effects. Your doctor will advise you on these and will monitor how you are feeling while the treatment progresses.

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