Burosumab
(Brand name: Crysvita®)
Burosumab is a new injectable drug treatment for those with X-linked hypophosphatemia (XLH). It works to help the body keep the phosphate levels that it needs. This can help to prevent fractures, bone pain, fatigue, strengthen your bones, and may increase your mobility. Burosumab will be available on the NHS from November 2024.
Burosumab Fact Sheet
Who can have burosumab?
Burosumab is recommended for individuals who have a genetic diagnosis of XLH who are over the age of 1. It’s worth bearing in mind that GPs won’t be able to prescribe burosumab, so you will need to see a specialist at a hospital. A specialist in metabolic bone may be a rheumatologist, endocrinologist or nephrologist.
When is burosumab not recommended?
- When you are also taking oral phosphate supplements and/or a specific form of vitamin D supplement (e.g. calcitriol, calciferol). You need to stop this before starting burosumab and your specialist centre will advise you when you need to do this, at least 7 days before starting.
- If you are pregnant or think you may be pregnant. There is not enough experience to know if burosumab may harm your unborn baby. We recognise it can take a long time to become pregnant so the specialists in the NHS are recommending burosumab can be continued up to when pregnancy is confirmed.
- If you are breastfeeding. There is not enough experience to know if burosumab passes into your breast milk.
- If you have certain kidney problems – your specialist centre will advise you about this.
What does treatment involve?
Burosumab involves giving yourself two injections just under the skin, once every 4 weeks in adults. It comes in 10mg, 20mg and 30mg vials, and you may be prescribed a combination of different vials to make up your dose.
You’ll be given clear instructions and shown how to give yourself the injections by homecare nurses who can come to your house. The homecare nurses generally visit 3 times to help you, or a member of your family, with the injections. If you can’t do the injections yourself, a family member or carer can do them for you.
You should do your two injections together every four weeks – one straight after the other. They can be given over/on/in the stomach area, upper thigh or buttocks. If possible, don’t give both injections in the exact same place. You can also have the injections in the outer area of your upper arm, but only if someone else does this for you. The manufacturer has produced a video illustrating how to inject.
Contributing to ongoing research
Please help us build evidence of the outcome of burosumab in adults!
Clinical evidence is still needed to demonstrate the impact of burosumab on adults, particularly those who are less symptomatic and those in the older age bracket. We are supporting University of Oxford’s efforts to build this evidence, and want to encourage everyone to sign up on the RUDY platform for the latest round of questions, which will form an important baseline to future research.
Are you an adult going onto burosumab or a family member? Join the RUDY study.
If you’re prescribed burosumab
If you are prescribed burosumab, it is important to take the time to consider all the benefits and risks of taking burosumab before starting treatment so that you feel informed and confident about starting.
You can download and read the manufacturers drug information here.
I was on burosumab but taken off it, can I go back on it?
If you were taken off burosumab because you moved from being classified as a child to an adult, you should talk to your specialist to determine whether you should go back on the treatment. If you came off the trial for other reasons, there is no change.
I’m doing well on phosphate, will my treatment change?
Please ensure that a specialist is monitoring your symptoms, phosphate dosing and blood work. Your treatment may not change if you are tolerating your current treatment plan.
I am thinking of starting a family. What is the recommendation?
It is important that you inform your specialist if you are trying for a baby or are breastfeeding.
What are the side effects of taking burosumab?
Please share any concerns with your clinical specialist.
Reported side effects are back pain; constipation; dizziness; headaches; increased risk of infection; movement disorders; muscle spasms. In many cases these have subsided as doses are adjusted.