Apitegromab, a treatment for SMA, will not be submitted for approval in the UK  

7 October 2026

Apitegromab, a new treatment designed to be used alongside some existing treatments for spinal muscular atrophy (SMA), has recently been approved in the US. However, the company behind the treatment does not currently plan to seek approval in the UK.

Scholar Rock the company that makes apitegromab, has told us that it has made the difficult decision to not submit an application to the Medicines and Healthcare products Regulatory Agency (MHRA) at this time. The MHRA decides which medicines can be prescribed in the UK.  

We know this news may be disappointing for many people affected by SMA who have been following developments of the treatment. 

This means apitegromab will not be available for people with SMA in the UK for now. However, Scholar Rock has told us it still hopes to bring apitegromab to the UK in the future.  

Anyone in the UK currently receiving apitegromab through an ongoing clinical trial will be able to continue accessing it through the trial. 

What is apitegromab?  

SMA is caused by changes in the SMN1 gene, which mean the body does not make enough of a protein called SMN. A similar gene called SMN2 can produce a small amount of SMN protein. Current SMA treatments, including nusinersen (Spinraza) and risdiplam (Evrysdi), help SMN2 produce more of this protein. 

Apitegromab works differently by blocking myostatin, a protein that limits muscle growth. By removing this natural “brake” on muscle growth, it may help people build and maintain muscle strength. It is designed to improve muscle function and be used alongside existing SMA treatments, rather than replacing them. 

Has apitegromab been tested in a clinical trial? 

Apitegromab has been tested in a Phase 3 clinical trial called SAPPHIRE, involving 188 people in several countries with SMA aged between two and 21. Everyone taking part was already receiving nusinersen or risdiplam. 

Participants received either apitegromab or a placebo alongside their existing treatment. A placebo does not contain the active medicine. 

Researchers measured motor function using the Hammersmith Functional Motor Scale Expanded (HFMSE), which looks at a person’s ability to carry out different movements and activities. 

After one year, children aged two to 12 who received apitegromab showed improvements in motor function compared with those receiving placebo. Data used to support its US approval showed that 34% of children receiving the approved dose improved by at least three points on the HFMSE, compared with 14% receiving placebo. 

Why is apitegromab available in the US but not the UK? 

Each country has its own system for approving medicines and deciding how people can access them. 

In the US, the Food and Drug Administration (FDA) approves medicines for use, but this does not mean everyone can automatically access them. Whether a treatment is covered can depend on a person’s health insurance or public healthcare programme. 

In the UK, medicines first need approval from the Medicines and Healthcare products Regulatory Agency (MHRA). There is then a separate process to decide whether they should be routinely available through the NHS. 

In England, this is usually decided by the National Institute for Health and Care Excellence (NICE), with Wales and Northern Ireland normally following NICE recommendations. Scotland has a separate process through the Scottish Medicines Consortium (SMC). 

Scholar Rock told us that the UK environment for accessing new medicines, particularly the processes for routine NHS access, played a part in its decision not to seek UK approval for apitegromab. 

One of our priorities is ensuring people in the UK can benefit from advances in treatment. We are working with partners to improve the UK environment for new treatments, so they can be properly assessed and, where they are shown to be safe and beneficial, reach the people who could benefit from them. 

Research into apitegromab is continuing  

Research into apitegromab for SMA is continuing, including studies looking at its longer-term effects and its use in children with SMA under two years old.  

Because apitegromab targets muscle, it could also potentially have benefits in other muscle wasting conditions. 

Scholar Rock is investigating it as a potential treatment for facioscapulohumeral muscular dystrophy (FSHD), with an early-stage clinical trial looking at whether it is safe and could benefit adults living with FSHD. 

We will continue to speak with Scholar Rock about its plans for apitegromab in SMA and other muscle wasting conditions, and keep you updated as we learn more.