SMA Treatment Delay FAQ
Last Updated: 08/08/26
We know our community has many pressing questions related to the FDA approval delay of Scholar Rock’s apitegromab. This FAQ was developed to address the most common concerns and provide the latest updates as we continue to work closely with Scholar Rock and the FDA.
Biogen's High Dose SPINRAZA (nusinersen), originally featured on this FAQ page, has been removed due to its FDA approval. Learn more about this approval here.
What is Cure SMA doing?
Cure SMA continues to regularly engage with and seek answers from the FDA and the companies regarding the treatment's next steps and timelines. We are also mapping out possible actions where we can have influence and impact, including elevating the urgent needs and goals of the SMA community. Please watch for future updates through Cure SMA. For more information on Cure SMA’s drug pipeline, please visit here.
Usually, after a CRL re-submission has been received (and accepted) by the FDA there is either a 2 month or a 6 month timeline for the FDA to decide on whether to approve. This is an area that Cure SMA will be working on now, to look for opportunities to get the FDA to work for a faster decision than the normal regulated periods.
We have recently conducted some direct advocacy initiatives with the new head of CDER at the FDA, along with several outreach efforts to legislative champions in the House and Senate. We expect to increase and broaden these efforts over the next weeks and months based on the decisions and timelines received back from the FDA on resubmission.
Cure SMA was present and active at the Type A FDA meeting on Apitegromab to represent our community to ensure that the patient voice and the patient need were heard and factored into decisions. In particular, stressing the urgency needed to address unmet needs across the entire age spectrum in SMA.
FDA History
References
August 2025
Cure SMA shares patient voice and needs with FDA
https://www.curesma.org/cure-sma-shares-patient-voice-and-needs-with-fda/
March 2025
SMA Community Risk Tolerance Update – Comparison of 2022 and 2017 SMA risk-Benefit Survey Data
https://www.curesma.org/sma-community-risk-tolerance-update-comparison-of-2022-and-2017-sma-risk-be…
https://www.curesma.org/wp-content/uploads/2025/02/SMA-Community-Risk-Tolerance-Update_02.25.pdf
July 2024
State of SMA Report (sent to FDA)
https://www.curesma.org/wp-content/uploads/2024/06/9042024_State-of-SMA_vWeb.pdf
August 2022
Cure SMA holds patient-led listening session with FDA
https://www.curesma.org/cure-sma-holds-patient-led-listening-session-with-fda/
If there are issues with the manufacturing - should those people who are on current dosage or through trials or EAP be concerned about the safety?
No, there are no current concerns with current approved product or product made for trials or EAP programs.
I would like to better understand what is meant by the reference to "unexpected manufacturing-related issues" in the context of FDA approval. My understanding is that capacity or supply chain limitations would not typically affect the FDA's decision to approve a pharmaceutical product. Should this instead be interpreted as concerns related to the quality, consistency, or sourcing of raw materials used in the manufacturing process?
This is correct that the FDA approvals are not linked to capacity items around making enough of new treatments. But they are involved in reviewing the quality and consistency of the manufacturing processes to make the new treatments. This is sometimes done in-person at the actual manufacturing sites and also with the documentation that tracks and details the specific manufacturing processes.
When will this drug and others that are not available, finally be available to Type 1 young adults?
While the issues raised here from the FDA are not about any concerns with efficacy or safety (which is a good thing, as those would significantly slow or stop this program), we do not have any new information yet on what the labels would be if and when they do get approved. However, we have been doing a lot of advocacy work over the last two years to reinforce the needs for approvals and labels to cover all with SMA, and especially those who are older in our community.
When is it realistic to expect approvals after this delay?
We do not know for certain, but based on past FDA actions, an approval decision on a re-submitted application could occur as soon as 3 to 5 months (under a shorter re-review process) or within 9 to 12 months (under a longer re-review process)
Apitegromab from Scholar Rock
On September 23, 2025, Scholar Rock announced that the U.S. Food and Drug Administration (FDA) has delayed the approval with a Complete Response Letter (CRL) for the apitegromab Biologics License Application (BLA) for the treatment of people living with spinal muscular atrophy (SMA). To read Scholar Rock's initial community statement, please click here. To read Scholar Rock's updated community statement as of 10/29/25, please click here.
On November 12, 2025, Scholar Rock, alongside Cure SMA, held an in-person Type A meeting with the FDA to discuss next steps for BLA resubmission. To read Scholar Rock’s community statement on these latest BLA updates, please click here.
On March 31, 2026, Scholar Rock announced that it had resubmitted its Biologics License Application (BLA) to the Food and Drug Administration (FDA) for apitegromab.
On Thursday, May 7, 2026, Scholar Rock announced that the FDA accepted its BLA for apitegromab.
On July 20, 2026, Scholar Rock announced that they would be engaging with the European Medicines Agency (EMA) on next steps to include the second fill-finish facility in the apitegromab marketing authorisation application (MAA).
On Friday, August 7, 2026, Scholar Rock announced that the apitegromab BLA is advancing with the second fill-finish facility, and that the BLA remains on track for potential FDA approval by the September 30, 2026 Prescription Drug User Free Act (PDUFA) action date.
Below are answers from Scholar Rock addressing initial questions from the SMA community.
What is apitegromab?
Apitegromab is an investigational muscle-targeted treatment for spinal muscular atrophy (SMA). It is the first muscle-targeted treatment candidate to demonstrate motor function improvement in a pivotal Phase 3 clinical study.
What is fill-finish facility?
A fill-finish facility is responsible for placing manufactured drug substance into its final container – such as a vial – and preparing it for distribution. This is separate from the facility that manufactures the drug substance itself.
What does the classification of Official Action Indicated (OAI) mean?
- OAI is a type of FDA classification for a facility that manufactures, processes, packs, or holds FDA regulated products. OAI typically means that FDA will require a satisfactory follow-up inspection of the facility before allowing any applications for new medicines that go through the facility to be approved for commercial use.
- Under the Agency’s guidance, FDA review of the apitegromab BLA will progress solely with the second fill-finish facility.
What does the OAI classification mean for apitegromab?
The OAI classification does not mean anything about the quality of apitegromab product. All apitegromab vials released for use in clinical trials or in the Expanded Access Program have met our established quality control standards.
Why is the second fill-finish facility necessary?
- While we had always planned to onboard additional manufacturing facilities into the apitegromab supply chain, we accelerated the process to onboard a second fill-finish facility.
- The inclusion of the second fill-finish facility in the apitegromab BLA provided two independent paths to a potential FDA approval.
- Under the Agency’s guidance, we are now removing the Catalent Indiana facility from the apitegromab BLA, and the FDA’s review of the application will continue with our second U.S.-based fill-finish facility.
- The BLA remains on track for potential FDA approval by the September 30, 2026 Prescription Drug User Free Act (PDUFA) action date.
Where is the second fill-finish facility located?
- The second fill-finish facility is located in the United States.
- The facility produces numerous commercial products and has demonstrated a strong track record of compliance, including recent successful FDA and EMA inspections.
Why is Scholar Rock using a third-party fill finish facility?
It is common for companies of our size to use a third-party fill-finish facility.
What is a Biologics License Application (BLA)?
A Biologics License Application (or BLA) is an application submitted to the U.S. Food and Drug Administration (FDA) seeking approval to make a treatment available in the United States.
When will the FDA issue an approval decision?
The BLA remains on track for potential FDA approval by the September 30, 2026 Prescription Drug User Free Act (PDUFA) action date.
When will apitegromab be available, if approved by FDA?
Our team is prepared to immediately launch apitegromab in the United States as soon as FDA approval is granted.
What about patients outside the U.S.?
- In Europe, the European Medicines Agency (EMA) review of our marketing authorization application (MAA) for apitegromab is ongoing.
- As indicated previously, with resolution of Catalent Indiana’s classification as OAI, we are now engaging with EMA on next steps to include Scholar Rock’s second fill-finish facility in the apitegromab MAA.
- Once there is alignment with EMA, we will provide updated timelines.
What is a marketing authorisation application (MAA)?
An MAA is the formal application that is submitted to the European Medicines Agency (EMA) to request approval to market a medicine in the European Union (EU).
Definitions:
Class 2 Resubmission review: The FDA’s standard six-month review timeline for a resubmission.
Class 1 Resubmission review: The FDA’s standard three-month review timeline for a resubmission
Complete Response Letter - CRL: The FDA’s way of saying “revise and resubmit” – aspects of the application need to be updated before FDA can complete its review and make a decision. The details of a CRL vary across drug applications. Receiving a CRL means that the review of the BLA or NDA has stopped and the FDA review will only continue when changes have been made and resubmitted. Once a BLA or NDA is resubmitted, a new review cycle starts.
CMC (Chemistry, Manufacturing, and Controls): What does CMC mean? In drug development, chemistry relates to the drug substance itself – its molecular structure, purity and stability. Manufacturing covers all the processes involved in producing the drug, from synthesizing the active ingredients to formulating the final product. Controls are the procedures put in place to guarantee that the drug consistently meets predefined quality standards throughout its entire lifecycle including determining its shelf life and storage conditions.