Will the NHS foot the bill for a new era of Alzheimer's drugs?

The first drug shown to slow brain destruction in Alzheimer's disease will no longer be available on the NHS following a decision by the medicines regulator.

The decision to fund lecanemab has caused upset and disappointment for people who had hoped the drug would help fight a terrible and devastating disease.

But the decision is not shocking.

Lecanemab is not a “magic bullet”: the European Medicines Agency looked at the same data as the UK and concluded that the drug should not be prescribed to anyone outside of clinical trials.

But what would it take to get drugs that slow the progression of Alzheimer's covered by the NHS?

The National Institute for Health and Care Excellence is tasked with figuring out how best to spend taxpayers' money – a place where emotion, real need and lobbying for treatments collide with strict cost-benefit calculations.

Drugs to treat dementia have been approved in the past to help manage symptoms such as confusion.

However, this is the first time that a drug that modifies the course of the disease has been evaluated – a common experience with other diseases. This summer, Enhertu, an anti-cancer drug that can extend the lives of incurable breast cancer patients, Denied Because it was too expensive.

But even with very expensive drugs, I One-off gene therapy The plans, which have an official cost of £2.6 million, could be approved if the benefits are large enough.

Lecanemab faces issues regarding its efficacy, cost, and safety.

It was hailed as the first drug to show any effect at slowing the progression of Alzheimer's. For a field that has seen so many failures, the release of the data in 2022 was a truly important moment. But I wrote at the timethe effect is small.

Lecanemab does not cure, reverse or stop Alzheimer's disease. It only slows the rate of decline.

In clinical trials, dementia continued to sap patients' brain power, but the decline slowed by about a quarter over 18 months of treatment. On an 18-point scale ranging from normal to severe dementia, patients given the drug improved by 0.45 points.

How meaningful these effects are remains a matter of intense debate among researchers.

Some argue that this would allow patients to live significant independent lives for longer. Others argue that the effect would be so small that doctors would not be able to tell the difference between patients receiving lecanemab or a placebo for 18 months. Others say patients should be able to make an informed choice about what is important to them.

Drug Data Born from extensive testing The study involved 1,795 volunteers with early stages of Alzheimer's disease, but they were healthier and younger than usual at the time of diagnosis. This raises the question of whether the drug “actually” works in older, frail people with multiple health conditions, and even in people with “mixed” dementia, where Alzheimer's may coexist with other illnesses.

The development of more powerful drugs that have a clear effect on the course of Alzheimer's disease could change the cost-effectiveness calculation.

It's still possible that lecanemab, starting treatment earlier in the disease or continuing treatment longer, may have a greater effect. This has yet to be proven.

Or maybe lecanemab will show the way, and future drugs that follow in its footsteps will bring greater benefits. Medical research often requires a first breakthrough discovery on which others can build. The first HIV drugs paved the way for modern antiretroviral therapies that ultimately give people a near-normal life expectancy.

Cost is on the other side of this equation: cheaper drugs must be less effective to meet the cost-effectiveness criteria.

Lecanemab is expensive: the drug itself costs around £20,000 per patient per year (based on US prices), but the surrounding care costs twice as much on the NHS (private rates can be even higher).

Because there are many types of dementia, expensive PET (positron emission tomography) scans or spinal punctures to obtain samples of cerebrospinal fluid are required to confirm that a patient actually has Alzheimer's before treatment can begin.

The drug would then require an intravenous infusion every two weeks, plus expensive brain scans to monitor for known side effects.

One option would be to negotiate a better price, and with other drugs such as donanemab coming soon, there would be competition that could bring the price down.

There's still time for that to happen: NICE is due to publish its proposed decision on Thursday, with a decision due to be finalised later this year.

But drug companies are hoping to recoup years of R&D costs in a field that has produced a number of expensive failures and stalled products.

Both lecanemab and donanemab are very expensive types of drugs called monoclonal antibodies. These are laboratory-made versions of antibodies that the immune system makes naturally to fight disease.

As treatments for Alzheimer's, the drugs are designed to target sticky proteins called amyloids that get stuck in the gaps between brain cells and are a key hallmark of the disease, and the antibodies remove them.

But these are difficult to design and manufacture, and inevitably expensive drugs. You can't get a monoclonal antibody for the price of aspirin.

Also, the drug is not approved for use in people who carry certain gene mutations that actually increase the risk of Alzheimer's disease, so genetic testing is required.

The risks of these drugs include brain swelling and bleeding, some of which can be fatal, and monitoring them is costly.

Blood tests for Alzheimer's, drugs that require fewer infusions or have fewer side effects, or better ways to predict who is at risk of side effects, could theoretically reduce the medical costs of these drugs as well.

But as it stands, treating the 70,000 people who are eligible for the drug in England could cost around £1.4bn a year, and the same in NHS costs – assessed as inappropriate spending taxpayer money on a drug widely considered to have a “small” impact.

This week is historic: the first drug has been approved that can slow the progression of Alzheimer's disease.

For decades, dementia was simply thought to be an inevitable part of aging, but then it became clear that it was an actual disease, and there is now optimism that we might be able to do something about it.