Fenfluramine - Questions and Answers

The following Q&A provides relates to the Final Appraisal Document recommending the use of fenfluramine for adults and children (aged 2 and above) for fenfluramine as an add-on therapy to two other anti-epileptic medicines.

As with any general medical guidance it is important to consult with your clinician before starting, stopping or changing individual treatment plans. This guidance is correct to the best of our knowledge at the time of publication (30.5.22). 

What is fenfluramine?

Fenfluramine (also known by its brand name ‘Fintepla’) is an anti-seizure medication licensed for ‘the treatment of seizures associated with Dravet syndrome as an add-on therapy to other anti-epileptic medicines for patients 2 years of age and older’.

Is fenfluramine available in the UK? 

Fenfluramine is licensed by the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK for the treatment of seizures associated with Dravet syndrome, as an add-on therapy to other anti-epileptic medicines for patients 2 years of age and older. However, until given a formal recommendation by NICE that it should be funded via the NHS, its availability is limited e.g. accessible via clinical trials and a compassionate use programme. 

Who is NICE and what is their role?

NICE stands for the ‘National Institute for Health and Care Excellence’. NICE is the body that decides which treatments should be funded by the NHS in England and Wales. In order to make these decisions, the organisation must review the safety, effectiveness and cost-effectiveness of new treatments. 

What does the positive FAD from NICE mean for patients with Dravet Syndrome?

This Final Appraisal Document marks the end of a long consultation deciding whether fenfluramine would be recommended as a treatment for Dravet Syndrome. Today’s announcement confirms that fenfluramine is recommended for the treatment of Dravet Syndrome, based on the following criteria:

Does the FAD mean that fenfluramine can now be prescribed for my child/adult with Dravet Syndrome?

There are still some steps to go before fenfluramine is ready to be prescribed by your local hospital. Availability also depends on whether you live in England, Wales, Scotland or Northern Ireland.

The FAD is a notification by NICE of their intention to issue a positive final technology appraisal guidance for fenfluramine, which is scheduled for 6th July 2022. Then local authorities are given 3 months in England and 2 months in Wales from the date of the final guidance to make fenfluramine available for prescription. Scotland and Northern Ireland follow a slightly different process, we hope to be able to update on these soon.

My child/adult is already receiving fenfluramine. Will this decision impact our current prescription?

No, this recommendation is not intended to affect treatment with fenfluramine that was started in the NHS before this guidance was published. People having treatment outside this recommendation may continue without change to the funding arrangements in place for them before this guidance was published, until they and their NHS clinician consider it appropriate to stop.

How does fenfluramine work?

It is not completely known how fenfluramine works. However, it is thought to work by increasing the activity in the brain of a natural substance called serotonin, and this may reduce seizures.

How effective is fenfluramine in treating seizures?

The NICE recommendation is based on clinical trial data demonstrating that fenfluramine, when added to standard of care medicines, has the potential to reduce seizures in a large percentage of patients with Dravet Syndrome, leading to improved seizure control and potential for better overall outcomes. However, it is important to bear in mind that Dravet Syndrome can be unpredictable so, like many of the current treatments, fenfluramine may not work for all.  

What side effects are associated with fenfluramine?

Like all medicines, some people may experience side effects with fenfluramine. According to clinical trial data in over 700 patients with Dravet Syndrome in international clinical trials. In these trials, fenfluramine was generally well tolerated. If you have any questions about potential side effects associated with fenfluramine, please raise these directly with your medical team. 

Is fenfluramine associated with an increased risk of cardiovascular side effects?

Fenfluramine was first developed as an anti-obesity medication for adults. It was withdrawn in 1997 due to cardiovascular side effects. In the clinical studies for the treatment of Dravet Syndrome, fenfluramine was given in lower doses than previously used to treat adult obesity and no increased risks were observed of cardiovascular side effects.

Because of historical association with cardiovascular side effects, prior to starting treatment, patients must undergo an echocardiogram to establish a baseline prior to initiating treatment and exclude any pre-existing valvular heart disease or pulmonary hypertension. Echocardiogram monitoring should be conducted every 6 months for the first 2 years and annually thereafter.

If you have any questions about potential side effects associated with fenfluramine, please raise these directly with your medical team. 

Who makes fenfluramine? 

When researchers discovered that fenfluramine may show benefit in patients with drug-resistant epilepsy, this prompted a new phase of scientific research. Low dose fenfluramine was developed by Zogenix International specifically for use in Dravet Syndrome and has now been studied in over 700 patients with Dravet Syndrome in international clinical trials. 

Zogenix is now part of UCB, following an acquisition announced in March 2022.