Andexanet alfa: a safety audit using OpenPrescribing Hospitals

Last year we wrote about trends and variation in the use of andexanet alfa across NHS hospitals in England. Since then, there have been some major developments surrounding the use of andexanet alfa. In this blog, the team and special guest Richard Buka, briefly summarise the key updates and show you how you can use OpenPrescribing to audit andexanet alfa use in your hospital or region.

What is andexanet alfa?

Andexanet alfa is licensed for reversing the effects of apixaban and rivaroxaban, two direct oral anticoagulants. The National Institute for Health and Clinical Excellence (NICE) recommends andexanet alfa as an option in the management of life-threatening gastrointestinal bleeding in patients taking apixaban or rivaroxaban. However, clinical trials of andexanet alfa showed uncertain benefit and a high risk of thromboembolic events. You can read more about the clinical evidence in a short review article written by Rich or listen to this podcast discussing the ANNEXA-I trial of andexanet alfa.

What did we find?

Between May 2021 and June 2025, 19,608 vials of andexanet alfa were issued in NHS trusts in England. There was wide variation in the timing and speed of uptake across NHS trusts. Substantial variation was also observed between NHS Regions in England. You can read the full findings which are openly available in the British Journal of Clinical Pharmacology. Since this paper was published in December 2025, the total now stands at ~25,500 vials (May 2021 to April 2026). The monthly number of vials of andexanet alfa issued in England is shown below.

A safety update from America

Coincidentally, a couple of days after the paper above was published, on 19th December 2025, the American drug safety body, the FDA, announced that it was withdrawing the drug from availability in the USA as they considered the risks of the product to outweigh its benefits.

The United Kingdom position

Nevertheless, andexanet alfa remains available in the UK and is the only licensed reversal agent for apixaban and rivaroxaban. The British Society for Haematology (BSH) has published a detailed position statement about the safety risks where they recommend:

• Clinicians should be aware that administration of andexanet alfa is associated with a significantly increased risk of thromboembolic events, particularly ischaemic stroke.
• If administration of andexanet alfa is being considered, clinicians should be aware that thromboembolic risk may outweigh benefit.
• If andexanet alfa is to be given, clinicians should ensure that it is only administered within its licensed indication.

We understand that several trusts have removed, or are going through the process of removing, the drug from formulary.

In order to support these recommendations, it will be essential to carry out good quality audits and reviews in local hospitals and regions. Here we show how you can use OpenPrescribing Hospitals to support this audit and review cycle for hospital trusts in England.

See how much andexanet alfa your organisation issues using OpenPrescribing Hospitals

The screenshot below is taken directly from OpenPrescribing Hospitals and uses a random selection of hospitals located along the M62 motorway in England. It shows the number of vials issued so far in 2026 at each organisation.

Doing your own analysis on OpenPrescribing Hospitals

All andexanet alfa supply for England can be seen at this link. Below is a step by step guide to analysing andexanet alfa on OpenPrescribing Hospitals.

To analyse use at your own trust:

1. Select Analyse from the home page
2. On the Analyse page
   1. Select product: Start typing andexanet and select the 200mg vials
   2. Select NHS Trust(s)
   3. Hit Run Analysis
3. You now have graphs showing andexanet alfa issuing for your selected trust(s), and a table showing the total number of vials issued
4. Share the analysis by clicking Share analysis or bookmark the link

We have also made a video explainer showing how to use the analyse page to look at andexanet use, in case that is easier to follow.

Stay up to date and track changes over time

You can sign up for email alerts to be notified as soon as new monthly data is available.

The data on OpenPrescribing Hospitals is updated shortly after new data is published by the NHS, which is approximately two-months after the end of the month of data submission. If you’re interested in following the impact of the BSH guidance, check back when data from May 2026 onwards become available using the analysis link you bookmarked above.

OpenPrescribing Hospitals only contains data for England. We have set out the information that you may use locally to build a case for OpenPrescribing in your country and obtain funding to support development.