The first biosimilars for breast cancer are now available on the NHS. But what is a biosimilar?

Friday 1 June 2018      Policy and campaigns blog
Male doctor speaking to female patient

Biosimilars have already been used by the NHS for several years to treat diseases such as arthritis and other cancers. The first biosimilars for breast cancer are now available on the NHS. But what is a biosimilar and what does this mean for breast cancer patients? Here we shine a spotlight on five commonly asked questions.

What are biosimilars?

A biosimilar is a drug that works in the same way as an existing biological drug, like trastuzumab (Herceptin).  

When a drug is first developed, it is protected by a patent, which means only the company that developed the drug can make and sell it. But once the patent expires, other companies can make their own version of the drug. 
With most drugs, this simply involves copying the original chemical formula. But biological therapies are very complex molecules, meaning it is not possible to copy them exactly. Instead, companies develop drugs which are not completely identical to the original drug but are highly similar in the way they work. This is why they are referred to as biosimilars.
This is what has happened with trastuzumab. The patent on the original drug, also known as Herceptin, recently expired, which has resulted in several companies producing biosimilars of the drug. These are the first biosimilars for breast cancer.

Why are biosimilars being introduced?

Biosimilars are generally provided at a much lower price than the original drug; it is estimated that they cost 20-50% less because of increased competition and reduced development costs. The NHS is facing continued financial difficulties therefore biosimilars offer an opportunity to provide this important treatment at a lower cost and the money saved can be used to improve other areas of treatment and care. 
So far, there are two biosimilars of Herceptin available for use on the NHS with another one expected to become available over the coming months.

Are biosimilars as effective as the original drug?

Unsurprisingly, this is the question most people ask, especially if they’re already receiving the original drug. When hearing that biosimilars are highly similar to the original drug, people may worry that they’re not completely identical. However, the NHS will only offer treatment with a biosimilar once the European Medicines Agency (EMA) has carefully looked at the evidence and decided the biosimilar is just as effective and safe as the original.

What does this mean for me? 

If you’ve been diagnosed with HER2+ breast cancer then you’re likely to receive trastuzumab. Depending on your circumstances you may receive a biosimilar. 

Currently, the original biologic drug (Herceptin) is given as a drip into a vein (intravenously) or as an injection under the skin (subcutaneously). The subcutaneous form of the drug is primarily used for women with early breast cancer after surgery. 

Trastuzumab biosimilars are only available intravenously.

  • If you’re already having the original drug intravenously, you may be advised to switch to a biosimilar. 
  • If you’re already having the original drug subcutaneously, you’re likely to continue having this rather than switching to an intravenous biosimilar. 
  • If you have not yet started treatment you may receive a biosimilar.

It’s important to talk to your breast care team and ask them any questions you may have about biosimilars. 

You can also find more information about your treatment on our health information page explaining trastuzumab biosimilars

What is Breast Cancer Now doing?

At Breast Cancer Now we’ve been speaking to breast cancer patients and healthcare professionals about biosimilars and developed several recommendations which we have been speaking to NHS decision-makers about. We believe it’s vital that patients are given the right information and support and that women already established on Herceptin have the opportunity for a full and honest discussion with their healthcare professional and that decisions to switch to a biosimilar are managed in partnership with patients. Ultimately, the introduction of biosimilars in breast cancer on the NHS must be handled responsibly and with care, consideration and transparency. 

Share your experiences 

Have you recently been switched to a biosimilar? Did you get the information and support you needed? Share your experiences and tell us your story.