Reported Reactions

Drugs › Antisense oligonucleotide

Brand name · Nusinersen

Spinraza: adverse event reports filed with FDA

7,451 reports list it as a suspect or interacting product, 2017–2026. Class: Antisense oligonucleotide.

7,451
reports as suspect product
0% of all reports · about 785 a year
591
reports, 12 months to June 2026
638 in the 12 months before
49%
marked serious by the reporter
39.7% across the class
10.2%
record death among outcomes, as reported
763 reports · not verified by FDA

Between January 2017 and June 2026, 7,451 adverse event reports received by FDA list the brand name Spinraza (nusinersen) as a suspect or interacting product. Reports that mention it only as a concomitant medication (54) are left out of every figure here.

In the 12 months to June 2026, 591 reports listed it, close to the 638 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 785 reports a year and 0% of the 20,646,523 reports in the database, and 71.3% of the reports for the antisense oligonucleotide class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are headache (7.2%), post lumbar puncture syndrome (6.9%) and procedural pain (5%). A report can list several reactions, so shares add to more than 100%; 614 different terms appear across these reports. Headache is recorded in 7.2% of these reports, a larger share than in the median antisense oligonucleotide drug (1%).

49% of the reports are marked serious by the reporter (39.7% across the class); 10.2% record death among the outcomes and 30.4% record hospitalisation, as reported. 61.9% of the reports came from consumers, and the largest patient age group is 2 to 11 (19.1%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

04793Jul 2021: 63Aug 2021: 60Sep 2021: 92Oct 2021: 93Nov 2021: 77Dec 2021: 822022Jan 2022: 75Feb 2022: 55Mar 2022: 76Apr 2022: 41May 2022: 49Jun 2022: 64Jul 2022: 50Aug 2022: 62Sep 2022: 60Oct 2022: 87Nov 2022: 87Dec 2022: 712023Jan 2023: 62Feb 2023: 62Mar 2023: 82Apr 2023: 66May 2023: 60Jun 2023: 60Jul 2023: 63Aug 2023: 50Sep 2023: 48Oct 2023: 44Nov 2023: 53Dec 2023: 492024Jan 2024: 51Feb 2024: 45Mar 2024: 50Apr 2024: 53May 2024: 44Jun 2024: 45Jul 2024: 39Aug 2024: 52Sep 2024: 61Oct 2024: 46Nov 2024: 60Dec 2024: 502025Jan 2025: 41Feb 2025: 53Mar 2025: 55Apr 2025: 64May 2025: 72Jun 2025: 45Jul 2025: 37Aug 2025: 53Sep 2025: 45Oct 2025: 33Nov 2025: 37Dec 2025: 482026Jan 2026: 42Feb 2026: 73Mar 2026: 78Apr 2026: 38May 2026: 47Jun 2026: 60

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

06091,2182017: 62920172018: 1,21820182019: 92720192020: 76920202021: 91520212022: 77720222023: 69920232024: 59620242025: 58320252026: 3382026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Spinraza reports recording the termmedian drug in antisense oligonucleotide

  1. Headachehead pain7.2%536
  2. Post lumbar puncture syndrome6.9%514
  3. Procedural painpain from a procedure5%375
  4. Pneumonialung infection4.8%359
  5. Pyrexiafever4.8%357
  6. Deaththe patient died; cause not stated by this term4.4%325
  7. Astheniaweakness or lack of energy3.8%284
  8. Vomitingbeing sick3.8%283
  9. Back painback pain3.4%252
  10. Scoliosis2.9%219
  11. Fatiguetiredness2.7%201
  12. Falla fall2.3%171
  13. Malaisegeneral feeling of being unwell2.3%171
  14. Nasopharyngitisa cold2.2%161
  15. Nauseafeeling sick2.2%161
  16. Painpain, site not specified2%150
  17. Influenzaflu2%147
  18. Muscular weaknessmuscle weakness1.8%136
  19. Respiratory failurethe lungs could not supply enough oxygen1.8%132
  20. Drug ineffectivethe medicine did not work as expected1.7%128
  21. Respiratory tract infectiona respiratory infection1.5%115
  22. Covid-19COVID-19 infection1.5%113
  23. Protein urine present1.4%106
  24. Spinal muscular atrophy1.4%104
  25. Rhinovirus infection1.3%99
  26. Coughcough1.3%96
  27. Dyspnoeashortness of breath1.3%95

Top 30 of 614 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 3 drugs in the antisense oligonucleotide class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death10.2%763
Life-threatening1.2%89
Hospitalisation (initial or prolonged)30.4%2,267
Disability0.3%26
Congenital anomaly0%3
Other serious14.3%1,069
Not serious51%3,800

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 10,452 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 28.1%607
2 to 1119.1%1,421
12 to 177.9%591
18 to 4415.8%1,176
45 to 645.5%407
65 to 740.8%63
75 and over0.2%13
Age not given42.6%3,173

Patient sex

Female45.8%3,414
Male44.3%3,303
Not given9.9%734

Who reported

Physician26.4%1,967
Pharmacist0.6%46
Other health professional10.9%812
Lawyer0%0
Consumer or non-health professional61.9%4,614
Not given0.2%12

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 74.4% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Spinal muscular atrophy5,89079%

The indication field is filled in by the reporter and is often blank; shares are of all 7,451 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Spinraza reports
Albuterol1391.9%
Evrysdi971.3%
Vitamin d921.2%
MiraLAX650.9%
Acetaminophen580.8%
Ergocalciferol550.7%
Zolgensma470.6%
Sodium chloride440.6%
Ibuprofen380.5%
Cholecalciferol360.5%

Other products listed in reports where Spinraza is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureSpinrazaAntisense oligonucleotideAll reports
Reports as suspect product7,45110,45220,646,523
Share of that pool—71.3%0%
Reports, latest 12 months591—1,332,454
Marked serious49%39.7%57.4%
Death recorded among outcomes, per 1,000 reports1027991
Hospitalisation recorded, per 1,000 reports304253213
Consumer-filed share61.9%48.8%45.8%
Top term, share of reportsHeadache 7.2%median 1%3%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the antisense oligonucleotide class

DrugName typeReportsLatest 12 monthsMarked serious
Exondys 51brand2,23745817.1%
Amondys 45brand76417415.3%

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Questions about Spinraza reports

How many adverse event reports has FDA received for Spinraza?

7,451 reports list Spinraza as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 591 of them arrived in the latest 12 months. Another 54 list it only as a concomitant medication.

What reactions are recorded in Spinraza reports?

headache (7.2%), post lumbar puncture syndrome (6.9%), procedural pain (5%), pneumonia (4.8%) and pyrexia (4.8%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Spinraza was responsible.

How serious are the reports?

49% are marked serious by the reporter. Among the outcomes recorded, 10.2% of reports include death and 30.4% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

consumer or non-health professional (61.9%), physician (26.4%) and other health professional (10.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Spinraza rising?

591 reports in the 12 months to June 2026, close to the 638 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Spinraza was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Spinraza?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Spinraza as a suspect or interacting product; reports listing it only as a concomitant medication (54) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.