Resource impact summary report | Tools and resources | Avapritinib for treating advanced systemic mastocytosis | Guidance

Recommendation

NICE has recommended avapritinib within its marketing authorisation as an option for treating advanced systemic mastocytosis (including aggressive systemic mastocytosis, systemic mastocytosis with an associated haematological neoplasm, and mast cell leukaemia) in adults. Avapritinib is only recommended if the company provides it according to the commercial arrangement.

Eligible population for avapritinib

Table 1 shows the population who are eligible for avapritinib and the number of people who are expected to have avapritinib in each of the next 5 years, including population growth.

**Table 1 Population expected to be eligible for and having avapritinib in England**
Eligible population and uptake	Current practice (without avapritinib)	2024–25	2025–26	2026–27	2027–28	2028–29
People eligible for avapritinib	93	94	95	95	96	97
Uptake of avapritinib (%)	0%	20%	45%	50%	50%	50%
Total number of people having avapritinib	0	19	43	48	48	49

The total number of people having avapritinib each year in table 1 includes people starting and continuing treatment in that year.

The following assumptions have been used to calculate the eligible population:

There are around 145 people with advanced systemic mastocytosis in England.
According to trial data from the company submission, around 93 people (64%) are eligible for treatment.

The uptake for avapritinib is based on expert clinical opinion.

Treatment options for the eligible population

Standard treatments for advanced systemic mastocytosis include midostaurin and cladribine. Midostaurin is used at first line, when possible, with cladribine mostly being used at second line or later.

**Table 2 Treatment options available for people with advanced systemic mastocytosis**
Drug	Administration	Strength, container type, quantity	Treatment duration (months)
Avapritinib	Oral	200 mg, 30 tablet	16.6
Midostaurin	Oral	25 mg, 56 capsule	23.0
Cladribine	Intravenous	10 mg, 1 vial	3.68

There are also some people currently having best supportive care. By offering avapritinib as a treatment option, the number of people having best supportive care will reduce. For more information about the treatment options, see the resource impact template.

Financial resource impact (cash items)

The company has a commercial arrangement. This makes avapritinib available to the NHS with a discount.

Users can input the confidential price of avapritinib and amend other variables in the resource impact template.

The payment mechanism for the technology is determined by the responsible commissioner and depends on the technology being classified as high cost.

We expect the resource impact of implementing the recommendations in England will be less than £5 million per year (or about £8,800 per 100,000 population, based on a population for England of 57.16 million). This is because the technology is a further treatment option, and the population size is small.

For further analysis or to calculate the financial impact of cash items, see the resource impact template.

Capacity impact

Both avapritinib and midostaurin are administered orally. Cladribine is administered intravenously. But, because few people have cladribine at first line, this is not expected to result in a significant capacity benefit.

There is a very low probability of grade 3 and above adverse events for avapritinib, midostaurin or cladribine . So, no capacity impact is expected.

For further analysis or to calculate the financial capacity impact from a commissioner (national) and provider (local) perspective, see the resource impact template.

Key information

Table 3 Key information

Time from publication to routine commissioning funding	90 days
Programme budgeting category	PB02I, Cancer, Haematological
Commissioner(s)	NHS England
Provider(s)	NHS hospital trusts
Pathway position	Avapritinib is positioned to be used at first or later lines of therapy, with the expectation that most people would have treatment at first line.

About this resource impact summary report

This resource impact summary report accompanies the NICE guidance on avapritinib for treating advanced systemic mastocytosis and should be read with it. See terms and conditions on the NICE website.

ISBN: 978-1-4731-6125-486