What are ‘generic’ and ‘biosimilar’ DMTs for MS?

‘Generic’ and ‘biosimilar’ DMTs (disease modifying therapies) are either identical or very similar versions of the original MS drug they’re based on. Generic drugs are identical to the original drug. Biosimilar drugs are very similar to the original drug.

A growing number of disease modifying therapies (DMTs) for MS now come with either ‘generic’ or ‘biosimilar’ versions.

Which kind depends on how the original drug is made and what’s in it. When a drug has a simple structure, drug companies can make a generic version of it. If it has a complex structure, they can make a biologic version.

Why are there now generic and biosimilar DMTs for MS?

There are now generic and biosimilar MS drugs because the patents for the original versions of these drugs have come to an end.

What is a drug patent?

When a drug company creates a new drug, they give it a brand name and register it under a patent. This means that, for a specific number of years, they are the only company that can make the drug. When the patent ends, other companies are allowed to make their own, cheaper versions of the drug, but under different brand names.

As time goes on, and as patents come to an end, we’ll see more DMTs that have either generic or biosimilar versions.

What is a generic version of a drug?

A generic version of a drug is an identical version of the original brand name drug. It’s made using the same process. The same chemical ingredients are mixed together that are in the original.

With the generic version, you take the same dose, in the same way and with the same possible side effects. Because it has the same ingredients as the original drug, it’s just as safe and works just as well. To make sure this is the case, a generic version goes through trials before it becomes available.

The cost of generic drugs

There is one significant difference between generic versions and the original branded drug: generics cost much less. That’s why the NHS uses lots of generic drugs for all sorts of medical conditions. Switching people from the original brand name drug to a generic version saves the NHS lots of money.

What is a biosimilar version of a drug?

A biosimilar is a version of a ‘biologic’ drug. ‘Biologic’ means these drugs are made using living organisms or cells taken from animals, humans or plants. This can involve things like proteins, genes or antibodies.

Biologic drugs have a complex structure made up of larger molecules. And they're made using a complex process with expensive cutting-edge technology.

Because these kind of drugs are complicated and use living organisms, you can only make a ‘biosimilar’ version that’s very close to the original but not 100% the same. But the new version will have the same type of active ingredient as the original drug.

NHS England says biosimilar versions of biologic drugs have been ‘shown not to have any clinically meaningful differences … in terms of quality, safety and efficacy’. That means they work just as well as the original, are just as safe, and have the same risk of side effects.

Licensing and approving biosimilars

Biosimilars are only made available if evidence shows they meet the same standards of safety and effectiveness as the original drug. That includes evidence from drug trials.

A biosimilar drug must go through the same approval process as the original drug before it gets the green light to be used by doctors. This process is run by the Medicines and Healthcare products Regulatory Agency (MHRA). Once the MHRA say yes to a biosimilar drug, it’s seen as just as good as the original.

Both the MHRA and NHS treat biosimilars as ‘interchangeable’ with the original drug. That means they can be swapped with no significant negative effects.

The cost of biosimilar drugs

Biologic drugs cost the NHS a huge amount of money. Because a biosimilar version costs much less, the NHS encourages doctors to use biologic drugs as soon as they become available. By saving this money, the NHS can put more money into its services.

Tyruko (natalizumab): the first highly effective biosimilar DMT

Tyruko is the first biosimilar for a highly effective DMT for MS. It's a biosimilar version of natalizumab. That's the active ingredient in Tysabri, which recently had its patent end.

By 2024 UK neurologists were moving patients from Tysabri over to Tyruko.

A study called the Antelope trial showed that Tyruko gets the same results as Tysabri and is just as safe. Apart from being much cheaper, the other main difference is that Tyruko’s licence is only for the infusion form of the drug. Tysabri has a licence for both infusion and injection.

Other biosimilar DMTs for MS

A growing number of DMTs for MS are biologics. So if there are new versions of these, they will be biosimilars.

Biologics for MS include all the ones that end in ‘mab’ (short for ‘monoclonal antibody’):

The patents for these drugs will be in force for quite a few years to come. So they won’t have biosimilar versions soon. But as patents end, we do expect to see biosimilars made.

Which DMTs for MS have generic or biosimilar versions?

Several DMTs for MS have generic or biosimilar versions, which people now get on the NHS:

When a company makes a generic version of a DMT, they might give it a new brand name. Or they can add the company’s name before or after the drug’s actual name, for example, fingolimod-Teva or Teva-fingolimod.

Table showing alternative names of DMTs
Drug name	Original brand name	Name of alternative version
glatiramer acetate	Copaxone	Brabio (generic version)
natalizumab	Tysabri	Tyruko (biosimilar version)
fingolimod	Gilenya	generic versions made by around a dozen companies
teriflunomide	Aubagio	generic versions made by four companies
dimethyl fumarate	Tecfidera	generic versions made by six companies

Outside of the UK there are more generic or biosimilar MS drugs in use, with other brand names.

Will I be switched to a generic or biosimilar DMT for MS?

You might be switched to a generic or biosimilar DMT for MS. The move to generics or biosimilars will happen over the coming years as patents end.

If you’re being treated with the original brand version of a DMT, it’s likely that one day a generic or biosimilar version will become available. Then you may be switched to the new, cheaper version.

Moving to biosimilars isn’t new on the NHS. They’ve been used for years to treat other conditions like arthritis and cancer.

Speak to your MS team

Ask your neurologist or a member of your MS team if the patent on your DMT will end in the near future, and what version of it you might get instead.

MHRA guidance says that if your doctor prescribes you a biosimilar, they should use its brand name on the prescription. That way it’s clear to you which drug you’re getting.

Do I have to switch to a generic or biosimilar drug?

When there’s a generic version of a DMT, the NHS won’t offer you a choice between it and the branded version. That’s because both have exactly the same active ingredients. Your neurologist should tell you if they move you on to a generic drug.

If you’re switching to a biosimilar drug, NHS England encourages doctors and patients to make this a shared decision. But shared decision making doesn’t mean you can expect to stay on a more expensive brand of drug. That’s because the original drug and its biosimilar are seen as ‘interchangeable’.

If you have concerns or questions about your DMT

Talk to your MS team or neurologist if you have any concerns. If you notice any unwanted or unexpected symptoms or side effects after switching to the new drug, mention this to the medical staff who look after you. You can also report these yourself through the Yellow Card scheme.

The other meaning of ‘generic drug’

When we talk about a generic drug, it can mean two things:

a version of a drug with the exact same active ingredients as the original
or it’s the name a drug has before it gets its brand name. This generic name describes the active ingredient in the drug

Before a drug gets its brand name

A new drug will first have a generic name, then its makers give it a brand name to sell it under. For example, when the DMT glatiramer acetate was created under that generic name, its makers gave it the brand name Copaxone.

This is why you’ll see two names on your DMT’s packaging. The brand name is usually larger (and easier to say). Its generic name is underneath in smaller lettering.

Different brand names for drugs with identical ingredients

Some DMTs are available with more than one brand name. For example, when the patent ended on Copaxone, another drug company started making their own cheaper generic version. They gave it a different brand name: Brabio. But they have the same active ingredient: glatiramer acetate.

So, if a doctor wants to give a patient glatiramer acetate, there are two brands available: the original Copaxone and the cheaper generic version Brabio.