You asked: Can we monitor the usage of biosimilars in secondary care using OpenPrescribing Hospitals?

Since launching OpenPrescribing Hospitals we have received lots of helpful feedback. The most common question has been - What about biosimilars?

At the moment, we can’t monitor the use of biosimilars using OpenPrescribing Hospitals. This is because, whilst the data are available in secondary care, the NHS does not disclose the brands used (including biosimilars) in open data, which we use for OpenPrescribing Hospitals. This is in contrast to primary care where data for branded and generic product usage in primary care have been openly available since 2010, including biosimilars.

Below Vicky has written a short description of what biosimilars are, why they are of interest and why you can monitor usage using openly available data in primary care but you can’t currently from open secondary care data.

What is a biosimilar and why do we want to monitor usage?

Briefly, a biosimilar medicine is a biological medicine that is highly similar and clinically equivalent (in terms of quality, safety, and efficacy) to an existing biological medicine. For more about biosimilars, NHS England has a great summary, ranging from what they are, to their commissioning and procurement. The use of biosimilars are recommended within the NHS England medicines optimisation opportunities since they offer the same clinical effectiveness and safety as their reference products, but usually at a substantially lower cost. Where substantial savings could be made, it is of interest to those working within organisations to rapidly see usage of these products.

Biosimilars in open primary care prescribing data

In primary care since 2010, the English Prescribing Dataset (EPD) has been openly available. The OpenPrescribing platform and other platforms use this dataset. Within this dataset, prescription level data are reported in dm+d format. Using the EPD it is possible to report the usage of biosimilars. It is possible because medicines are included in the dataset as the actual medicinal product that was prescribed (AMP in dm+d terms). In other words it is a real product description. It describes a medicine or device that has been made available by a specific manufacturer or supplier, much like when a prescriber prescribes by brand.

Therefore if an individual patient were actually prescribed a biosimilar that information is available in the EPD and via analytic platforms such as OpenPrescribing.net. This means that users of OpenPrescribing can rapidly run analyses to see how their organisation is performing in terms of biosimilars.

For example:

Arovi, Inhixa and Ledraxen are biosimilar products for the low molecular weight heparin enoxaparin. Using OpenPrescribing, users can carry out analyses on the uptake and variation of biosimilar products such as enoxaparin.

In this plot, generated on the analyse page of OpenPrescribing, the number of biosimilar products for every 1000 items of enoxaparin, broken down by NHS region, are shown for May 2025.

What about secondary care?

The secondary care medicines dataset (SCMD) became openly available in 2020, and currently includes pharmacy stock data dating back to 2019. The openly available SCMD only goes down to the level of virtual medicinal products (VMP in dm+d terms). In other words, using the example above, we know that enoxaparin has been issued but we don’t know if it was issued as a biosimilar or not.

Data for the use of biosimilars is available for those with password access to Model Hospitals via the Model Health System and via Rx-Info using the Define product.

Summary

We would love to be able to offer biosimilar data on OpenPrescribing Hospitals and to build measures to support our users monitor the use of biosimilar products in their organisation. Although the NHS has this data and makes it available for primary care, unfortunately it is not currently openly available for hospitals. If and when it becomes available we will be delighted to explore and include it within OpenPrescribing Hospitals.