Generic and biosimilar drugs in MS

Disease modifying drugs, known as DMDs or DMTs, can be classified into two types: chemical medicines and biological medicines.

Chemical medicines are made from synthetic substances through a chemical process. They are often simple chemical structures. Biological medications are made from living sources, such as animal cells, plant cells, bacteria or yeast, through a complex biotechnological process. The resulting drug molecule tends to be a larger, more complex structure and can have some natural variation in the end product.

Pharmaceutical companies can spend years and large amounts of money developing and testing a new drug. Once it is ready, the company can apply for a patent, which protects their investment for a certain period of time. During this time, they are the only company legally allowed to make and sell the drug.

When the patent of a chemical medicine expires, other manufacturers can produce and sell a copy. This copy is called a generic medicine. A generic medicine has the same active ingredient, strength, dosage and method of administration as the original drug. It also has the same safety and effectiveness as the original medication.

When the patent of a biological medicine expires, other manufacturers can produce and sell a similar version of the original drug. This similar version is called a biosimilar medicine. A biosimilar medicine has the same mechanism of action and works in the same way as the original drug. It is not identical to the original medicine because of natural variations in the living sources used to make it. It also has to meet the same standards of safety and effectiveness as the original medicine.

The NHS uses generic and biosimilar medications to provide effective treatment options for people at a lower cost. An original drug is often costly to the NHS due to the years of research needed to discover and develop it. Although they must still complete trials for safety and effectiveness, generics and biosimilars are cheaper because they can be developed faster,

The NHS has been using generics and biosimilars safely for several years for conditions including cancer and arthritis. 

At the time of writing, there are only a few approved generic and biosimilar DMDs for MS in the UK. More have been approved in the US and Europe and may come to the UK in the future. 

There are several generic versions of Copaxone (glatiramer acetate) available in the NHS. Some people prescribed this drug may have already been offered a switch from Copaxone to Glatopa or Brabio. More recently, a biosimilar alternative to Tysabri (natalizumab) called Tyruko has been introduced in some parts of the UK.

Many other drugs used to treat symptoms in MS are generics. You may already be taking one. Baclofen is a generic version of a drug previously marketed as Lyflex or Lioresal. Pregabalin is a generic version of a drug first sold under the name of Lyrica. Although Viagra is the famous name, you are more likely to be prescribed with the generic drug sildenafil citrate.

Our A-Z page on disease modifying drugs has an up-to-date list of licensed DMDs. For other drugs used to treat MS symptoms, you will find alternative names on the A-Z page for each drug.

• NHS England: Biosimilar medicines Explains more on what a biosimilar medicine is and how it can be used.
• The Medicines and Health products Regulatory Agency (MHRA)  Read more about the process for evaluating the safety and efficacy of drugs in the UK.