WHY SPINRAZA? / LOW DOSE REGIMEN EFFICACY

A study in patients with SMA showed SPINRAZA® (nusinersen)

Achieved meaningful results across
age
groups—from infants to adults1-3

Backed by the longest clinical trial
program to date in infants and
children.4 Supported by extensive
real-world evidence in
adults, teens,
and older children2,3,5

Click the tabs to see the data in the selected population
SPINRAZA for EARLY-ONSET SMA

ENDEAR

The first clinical trial showing proven effects on SMA1,4,6

Pivotal trial: ENDEAR1,6

Study overview: A phase 3, multicenter, double-blind, randomized (2:1), sham-controlled trial of the Low Dose Regimen (12 mg loading doses/12 mg maintenance doses)

Study duration: 13 months

Participants: 121 patients with early-onset SMA aged ≤7 months at time of first dose

Primary endpoints: Survival without the need for permanent ventilation and proportion of patients meeting the criteria for motor milestone responder using HINE-2

Safety: The most common adverse reactions were lower respiratory infection (55%) and constipation (35%). Serious adverse reactions of atelectasis were more frequent in SPINRAZA-treated patients (18%) than in control patients (10%) 

HINE-2, Hammersmith Infant Neurological Exam Section 2; SMA, spinal muscular atrophy.

SEE ADDITIONAL SPINRAZA SAFETY
Low Dose SPINRAZA increased event-free survival compared to sham control1,6
Primary endpoint: No death or use of permanent assisted ventilation*

Learn more about the mobility measures used in the SPINRAZA clinical trials.

MEASURES OF MOBILITY TOOL

*Permanent ventilation was defined as tracheostomy or ventilatory support for ≥16 hours per day for >21 continuous days in the absence of an acute reversible event.

CI, confidence interval; HR, hazard ratio.

Those with SMA type 1 saw improvements in motor milestones that are rarely, if ever, achieved in untreated children6
51% (37/73) of patients treated with Low Dose SPINRAZA vs 0% (0/73) of sham control patients met the motor milestone responder criteria as defined by HINE-2† at 13 months.1 Motor milestones included6:

ϯA treatment responder was defined as any patient achieving an improvement in more categories of motor milestones than worsening according to HINE-2. P<0.0001.1,6

Patients treated with SPINRAZA continued to improve over time, as measured at Day 394, while untreated patients saw a decline in motor milestones6

The ENDEAR trial concluded early because of the results of the interim analysis, hence why not all patients were assessed at Day 394.

Mean change in HINE-2 total motor milestone score over time

SEM, standard error of the mean.

Review the Warnings and Precautions, including thrombocytopenia, coagulation abnormalities, and renal toxicity1

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INDICATION

SPINRAZA® (nusinersen) is indicated for the treatment of spinal muscular atrophy (SMA) in pediatric and adult patients.

IMPORTANT SAFETY INFORMATION

Coagulation abnormalities and thrombocytopenia, including acute severe thrombocytopenia, have been observed after administration of some antisense oligonucleotides. Patients may be at increased risk of bleeding complications.

In the sham-controlled studies for patients with infantile-onset (Study 1) and later-onset (Study 2) SMA who received Low Dose Regimen (12 mg loading doses/12 mg maintenance doses), 24 of 146 SPINRAZA-treated patients (16%) with high, normal, or unknown platelet count at baseline developed a platelet level below the lower limit of normal, compared to 10 of 72 sham-controlled patients (14%). Two SPINRAZA-treated patients developed platelet counts <50,000 cells per microliter, with the lowest level of 10,000 cells per microliter recorded on study day 28. In patients who received High Dose Regimen (50 mg loading doses/28 mg maintenance doses), decreases in platelet counts were also observed.

Renal toxicity, including potentially fatal glomerulonephritis, has been observed after administration of some antisense oligonucleotides. SPINRAZA is present in and excreted by the kidney. In Study 1 and Study 2, 71 of 123 SPINRAZA-treated patients (58%) had elevated urine protein, compared to 22 of 65 sham-controlled patients (34%).

Laboratory testing and monitoring to assess safety should be conducted. Perform a platelet count, coagulation laboratory testing, and quantitative spot urine protein testing at baseline and prior to each dose of SPINRAZA and as clinically needed.

Severe hyponatremia was reported in an infant treated with SPINRAZA requiring salt supplementation for 14 months.

Cases of rash were reported in patients treated with SPINRAZA.

SPINRAZA may cause a reduction in growth as measured by height when administered to infants, as suggested by observations from the controlled study. It is unknown whether any effect of SPINRAZA on growth would be reversible with cessation of treatment.

The most common adverse reactions in the Low Dose Regimen (≥20% of SPINRAZA-treated patients and ≥5% more frequently than in control patients) that occurred in the infantile-onset controlled study were lower respiratory infection and constipation. Serious adverse reactions of atelectasis were more frequent in SPINRAZA-treated patients (18%) than in control patients (10%). Because patients in this controlled study were infants, adverse reactions that are verbally reported could not be assessed. The most common adverse reactions that occurred in the later-onset controlled study were pyrexia, headache, vomiting, and back pain. Post-lumbar puncture syndrome has also been observed after the administration of SPINRAZA.

The most common adverse reactions in the High Dose Regimen (≥10% of SPINRAZA-treated patients and ≥5% more frequently than control patients from Study 1) that occurred in patients with infantile-onset SMA were pneumonia, COVID-19, pneumonia aspiration, and malnutrition. COVID-19 was not discovered at the time of Study 1.

Please see full Prescribing Information.

References

1. SPINRAZA. Prescribing Information. Biogen; 2026. 2. Łusakowska A, Wójcik A, Frączek A, et al. Long-term nusinersen treatment across a wide spectrum of spinal muscular atrophy severity: a real-world experience. Orphanet J Rare Dis. 2023;18(1):230. doi:10.1186/s13023-023-02769-4 3. Günther R, Wurster CD, Brakemeier S, et al. Long-term efficacy and safety of nusinersen in adults with 5q spinal muscular atrophy: a prospective European multinational observational study. Lancet Reg Health Eur. 2024;39:100862. doi:10.1016/j.lanepe.2024.100862 4. Biogen Data on File as of 04/26. 5. Hagenacker T, Paradis AD, Lawson-Michod KA, Youn B. Systematic review and meta-analysis of long-term nusinersen effectiveness in adolescents and adults with spinal muscular atrophy. Adv Ther. 2025;42(9):4143-4160. doi:10.1007/s12325-025-03260-1. 6. Finkel RS, Mercuri E, Darras BT, et al; ENDEAR Study Group. Nusinersen versus sham control in infantile-onset spinal muscular atrophy. N Engl J Med. 2017;377(18):1723-1732. doi:10.1056/NEJMoa1702752

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