What is Rituximab?
Rituximab is a targeted DMARD (Disease modifying anti-rheumatic drug), which works to dampen down the body’s inflammatory response. In certain diseases the immune system is over active, this can target healthy tissues such as joints and blood vessels. Rituximab works to reduce the inflammatory response by blocking the immune cells called B cells. B cells make proteins that attack the normal body by mistake. Blocking these cells reduces inflammation; thereby reducing symptoms such as pain, joint swelling and tissue damage.
What is Rituximab used for?
Rituximab is used for a few different types of conditions in rheumatology. These include:
It can take up to 4 months to have an effect in arthritis and longer in other inflammatory diseases.
How is it taken?
Rituximab is given as a drip directly into a vein, this is also known as an infusion. It is usually given in addition to the other medications you are taking such as methotrexate.
The infusion is given slowly and the dose increased in steps to ensure that you don’t develop side effects. Your blood pressure and observations are monitored throughout. The drip takes around 6 hours to give the total dose of 1000mg. It is then repeated for a second infusion of 1000mg, 2 weeks later on day 15.
The infusion is usually given in the Rheumatology day unit.
Medications to help prevent side effects are given at the same time; these include steroids, paracetamol and antihistamines.
If you tolerate the infusion well, it can be given quicker in subsequent doses. The doses are usually given when you begin to flare, this is at least 6 months after the 1stcourse. Some patients manage well and do not need another course for up to 1 year.
Before each dose of rituximab, you will need to have your bloods checked to ensure that your blood counts, liver and kidney function are stable.
Before your first infusion, your bloods will also be checked for immunoglobulin’s to ensure that we do not cause your immune system to be reduced too much.
Sometimes rituximab can cause a reaction during the infusion. The chance is reduced as medications are given alongside it to prevent this from happening.
Other possible side effects include:
- Increased risk of infection
- Rituximab lowers the immune system making you more prone to infection.
- If you are unwell or require antibiotics, your infusion will need to be delayed.
- As the effects can last months, you should see your GP if you become unwell in case you need antibiotics.
- Progressive Mulitfocal Leukoencephalopathy (PML)
- This is a very rare side effect that has been previously reported. It is a virus that can affect the brain and spinal cord and can be serious.
- If you develop symptoms like loss of balance, clumsiness or a change in the feeling of your arms and legs, seek urgent medical attention.
Cautions of use
Interactions with other medications
- Your doctor and pharmacist will check that rituximab does not interact with any of your regular medications.
Contraindications of other conditions
- Before starting any biological therapy, your bloods will be checked for infections that can become active again when the immune system is suppressed, this includes hepatitis B, C and HIV. A blood and chest X-ray is taken to exclude previous TB exposure. If you are found to have had previous TB exposure you may need to start preventative antibiotics for a short period before the rituximab is commenced.
- Rituximab should be avoided in patients with severe heart disease.
- Infusions should be delayed during active infections.
- You should avoid contact with those that have chicken pox or shingles.
- Surgery should be planned for at least 4 months after the infusions.
During pregnancy and breastfeeding
- Rituximab is not safe in pregnancy or breastfeeding.
- It should be stopped 6 months prior to conceiving.
- Data is limited but there is some evidence to suggest it may be safe in males trying to conceive.
- Alcohol does not interact with rituximab.
- It is recommended to take alcohol within moderation, following the guidelines of less than 14 units weekly.
- Non-live vaccines such as flu and the pneumonia vaccine should be given 4 weeks before the rituximab to ensure the full response.
- Live vaccines such as shingles should be avoided 4 weeks before rituximab and for 6 months after the last dose.
Versus Arthritis: http://www.versusarthritis.org