Your Monthly Medicines Roundup for December 2025

December was a quiet month in terms of medicines for inherited metabolic disorders being appraised. Only an update for a potential new treatment option for familial chylomicronemia syndrome was issued. We also look at what other updates we expect to see in 2026. 

Plozasiran, a medicine which can treat familial chylomicronaemia syndrome (FCS), is progressing through the NICE process in England. The invitation to participate in the appraisal has now been shared with all stakeholders and a deadline has been set. Within this scope, we are working with Action FCS and have put together a survey to collect people’s experiences. This survey has now closed as the experiences we collected are also being used for the appraisal of olezarsen, which is on slightly earlier timelines. See our November update for more information.  

Further details for plozasiran can be found here:

Below are the expected updates for the upcoming year:

We are expecting the appraisal for pegzilarginase for people with arginase 1 deficiency to come to a final recommendation in England this year. It is yet unclear whether this will be positive or negative and we will share an update as soon as more information is available. 

Since 2019, a Managed Access Agreement has been in place for people with Batten disease to receive cerliponase alfa. From 2023, the results generated by the managed access agreement were assessed by NICE in England to decide whether cerliponase alfa can become routinely available on the NHS. By mid-2025, NICE had reached the conclusion that they were unable to recommend the treatment. This was appealed by the company and a final recommendation is now expected in 2026.  

Two different treatments, olezarsen and plozasiran, will be assessed by NICE in England this year, as a new treatment option for people with familial chylomicronaemia. A final recommendation is currently expected in the second half of 2026, but timelines are still subject to change. 

A new HealthTech guidance for ex-situ machine perfusion devices for deceased donor liver transplants was initiated by NICE in England mid-2025. This is anticipated to come to a close mid-2026. 

We expect the assessment by NICE in England of triheptanoin for people with long-chain fatty acid oxidation disorders to resume this year. Once more information about timelines is available, we will share this. 

Obicetrapib and obicetrapib–ezetimibe will be assessed by NICE in England this year as a new treatment option for people with primary hypercholesterolaemia or mixed dyslipidaemia. A final recommendation is currently expected in the second half of 2026, but timelines are still subject to change. 

We expect the assessment by NICE in England of doxecitine–doxribtimine for people with thymidine kinase 2 deficiency to be resumed this year. Once more information about timelines is available, we will share this. 

We are keeping track of a number of other new treatments for inherited metabolic disorders across England and Scotland, incl. efzimfotase alfa for people with hypophosphatasia and PXT3003 for people with Charcot-Marie-Tooth disease type 1A. We will provide updates in our monthly medicines round-up once public updates are available. Wales and Northern Ireland work with a “recognition model”, which means that they copy the recommendation made by NICE in England. Occasionally, separate submissions are made to Wales, which we will keep track of.