These FAQs are published by VHL UK/Ireland in partnership with Dr Scott Shepard. Last Updated: September 2025
1. What is VHL?
Von Hippel-Lindau disease (VHL) is a devastating, rare, life-long, incurable disease, which can cause multiple, malignant, and benign tumours/cysts throughout the body. Tumours can occur in multiple organs at the same time or recur over a person’s lifetime and can be life-threatening. VHL does not go into remission, tumours do not shrink naturally and there is no cure.
Until now, often high risk, invasive surgery has been the only way to remove these tumours, and it is not uncommon for patients to their lose sight, part or whole organs and in a number of cases, patients suffer neurological issues such as paralysis after spine or brain surgery.
This condition affects all aspects of the patient and their carers lives including family planning, education, careers, leisure and travel, relationships, mental wellbeing and their ability to plan for the future.
2. What is Belzutifan (Welireg)?
Belzutifan (Welireg) is a first-in-class targeted therapy known as a hypoxia-inducible factor 2-alpha (HIF-2α) inhibitor. It works by blocking a key protein involved in tumour growth in people with VHL. On 5th September 2024, the National Institute for Health and Care Excellence (NICE) published its final draft guidance recommending Belzutifan (Welireg) for use under a Managed Access Agreement (MAA) in NHS England (NHSE).
Link: Final Draft Guidance for NHS England
Link: See All Project Documents
At the time, Chair of VHL UK/Ireland, Graham Lovitt said:
“We are delighted by NICE’s recommendation of belzutifan (Welireg) under the MAA, a significant milestone in the fight against this rare disease. This decision brings hope to qualifying patients and their families, offering them an alternative treatment option, when others become too high risk. VHL UK/Ireland remains committed to supporting those affected by the condition and helping everyone who can benefit from this breakthrough medicine to access it”.
3. What is a Managed Access Agreement (MAA)?
The MAA is an agreement between the National Institute for Health Care and Excellence (NICE), NHS England and the pharmaceutical company Merck, Sharp & Dohme (UK) Ltd (MSD) to allow controlled prescriptions for belzutifan (Welireg) to be given to VHL patients under the conditional terms of its approval by the Medicines and Healthcare products Regulatory Agency (MHRA) approval.
4. What is the Cancer Drugs Fund (CDF)?
The CDF is a mechanism used by the National Institute for Health Care and Excellence (NICE) and NHS England (NHSE) to fund a promising new drug where the trial data hasn’t provided sufficient evidence to prove the long-term efficacy and economic benefits of the drug. Data collected during this period will help NICE determine whether belzutifan (Welireg) should receive routine commissioning in future.
5. Why has full access not been granted for belzutifan (Welireg)?
Although clinical trials in the USA have shown excellent results for patients taking belzutifan (Welireg), the National Institute for Health Care and Excellence (NICE) feels that there is insufficient evidence at the current time to give full approval in England. The Managed Access Agreement (MAA) gives a period of 5 years (usually this is only 2 years, but as VHL is so rare and complex, the additional time period has been accepted by NICE) to gather further evidence as to both the efficacy of the drug and its economic benefit to NHS England.
6. Am I eligible?
It is important to remember that each country issues its own licence for a new medicine. The prescribing criteria can vary greatly. Each patient’s case will need to be assessed individually. The charity’s view is that the following are important to note:
- The estimate from NHSE is that approximately 100 patients in England may access the drug in the first year. This is an estimate, not a “cap”
- Other very individual criteria will be considered such as a patient’s age, general health and previous surgical outcomes
There is a list of eligibility criteria for belzutifan (Welireg) in the MAA which you can find on page 5 of that document (TA1011 Belzutifan (Welireg) for treating tumours associated with von Hippel-Lindau disease: managed access agreement 16/10/2024 (nice.org.uk)) but in summary you:
- Must be an adult (over 18) with a VHL germline alteration.
- Have a diagnosis of a renal cell carcinoma (kidney tumour), CNS hemangioblastoma (brain or spine), or pancreatic neuroendocrine tumour where localised treatments (like surgery or ablation) are considered unsuitable.
- Be at a point where further surgery is likely to have significant consequences for your quality of life.
- Have not previously been treated with belzutifan (Welireg) or any hypoxia-inducible factor 2 alpha (HIF-2ɑ) inhibitor unless via a company compassionate access scheme and other MAA criteria are met.
If in doubt, please speak with your medical team.
7. How quickly can I access belzutifan (Welireg) in England?
As long as you qualify, immediately – but it can only be prescribed by a consultant specialist specifically trained and accredited in the use of systemic anti-cancer therapy (an oncologist).
8. How do I get a prescription?
Speak to your oncologist and ask if you may be eligible. The Managed Access Agreement means that prescriptions for belzutifan (Welireg) can only be given by a consultant specialist specifically trained and accredited in the use of systemic anti-cancer therapy (an oncologist). If you are not already under the care of an oncologist you can ask your consultant or GP to refer you to one.
Please also see advice given in FAQ 11 for further information on access.
9. What are the likely side effects?
The most common side effects seen in clinical trials included anaemia, fatigue, shortness of breath, and dizziness. Rarely, belzutifan (Welireg) can cause dangerously low oxygen levels (hypoxia), which is why your team will monitor you closely.
Your oncologist will monitor you for any known side effects, but please speak with your oncologist as soon as possible if you become aware of any symptoms which you believe may be side effects. You will also need to carry a medical health alert card.
More information is available here:
https://bnf.nice.org.uk/drugs/belzutifan-specialist-drug
https://www.drugs.com/pregnancy/belzutifan.html
https://medlineplus.gov/druginfo/meds/a621047.html
10. What do I need to be aware of regarding belzutifan (Welireg) and family planning?
10.1 Pregnancy
Belzutifan (Welireg) may harm your unborn baby and cause a miscarriage. Your doctor will carry out a pregnancy test before you start taking the medicine.
This means:
• You should not become pregnant while taking belzutifan (Welireg)
• You should not take belzutifan (Welireg) if you are pregnant
If you are a man whose female partner could get pregnant:
• You and your partner should use effective contraception while taking belzutifan (Welireg).
• Also do this for at least 1 week after your last dose of belzutifan (Welireg).
If your partner becomes pregnant while you are using belzutifan (Welireg), talk to your doctor straight away.
If you are a man whose female partner is pregnant:
Use a barrier method of contraception during treatment with belzutifan (Welireg) and 1 week after last dose.
10.2 Breastfeeding
Do not breastfeed during treatment with belzutifan (Welireg). It is not known if belzutifan (Welireg) passes into your breast milk; it may harm your baby.
You should not breastfeed for at least one week after your last dose of belzutifan (Welireg).
10.3 Fertility
Belzutifan (Welireg) may impair fertility. If you are planning to have a baby with your partner – talk to your doctor about family planning before taking belzutifan (Welireg). If you are of reproductive age, your oncology team may offer you the opportunity to discuss fertility preservation before starting treatment.
More information can be found on these topics via the links in FAQ 9.
11. I am being told I do not qualify for belzutifan (Welireg) and I disagree, what can I do?
Each patient’s eligibility for belzutifan (Welireg) must be assessed individually by their medical team, based on the criteria set out in the Managed Access Agreement (MAA) and the UK MHRA licence. This process is designed to ensure that the medicine is used safely and effectively, and at the right time in the course of VHL.
Belzutifan (Welireg) is a long-term treatment, and timing is important—starting it too early or too late may reduce its benefit. Clinicians are expected to work in partnership with patients to weigh up the risks and benefits, and to decide on the best moment to start treatment based on your individual circumstances.
Because access to belzutifan (Welireg) is still new in England, clinical processes and referral pathways are evolving. In the meantime, here is what the charity recommends if you have concerns about your eligibility:
- Ask your clinician for a clear explanation, in writing, about why you do not currently meet the criteria for belzutifan (Welireg).
- Ask whether an oncologist with expertise in systemic anti-cancer therapies has been involved in your case.
- If not, ask your clinician if they would be willing to contact the charity at support@vhl-uk-ireland.org. We can then help connect them with the relevant clinical leads. (Please note: While the charity and members of the VHL Clinical Forum cannot offer direct clinical advice to individual patients or carers, we can and do support patients in navigating eligibility criteria and accessing expert opinion. If your doctor would find it helpful, they are welcome to get in touch).
A national VHL Clinical Forum has been established by a coalition of UK medical experts. This virtual group meets regularly to discuss referrals and support consistent, expert-led decision-making across the country. The aim is to ensure all patients are assessed using the same fair and transparent criteria, and that difficult cases are reviewed by specialists with deep knowledge of VHL.
If you are not currently considered eligible for treatment, it does not mean you will never be eligible. Your case should remain under review, and your medical team will continue to monitor for any changes. If your situation evolves, you may be reconsidered for belzutifan (Welireg) in the future.
12. Is belzutifan (Welireg) recommended in other areas of the UK?
The charity understands that similar managed access in Wales is in line with National Institute for Health Care and Excellence (NICE)/NHS England guidance from November 5th, 2024. Please check with your clinician.
Scotland has already fully approved the drug for use under the terms of the Medicines and Healthcare products Regulatory Agency (MHRA) approval.
The charity is currently uncertain about access for Northern Ireland patients and whether it is covered by the current MHRA licence. We suggest the best course of action is to speak with your clinician. We will share any updates as soon as they are available.
The Republic of Ireland (ROI) is in the EU. Belzutifan (Welireg) now has marketing authorisation in the EU and the process for funding in ROI has begun and is ongoing. We will update when we have any more information.
13. Accessing belzutifan (Welireg) outside of the UK/Ireland
If you live outside of the UK/Ireland and are seeking access to belzutifan please read our advice here: Accessing belzutifan from outside the UK
