STARTING SPINRAZA / DOSING & ADMINISTRATION

SPINRAZA® (nusinersen) is delivered directly to the CSF with two dosing regimens available1

High Dose SPINRAZA for SMA patients1

Dosing schedules for High Dose SPINRAZA are shown below.

SPINRAZA is administered intrathecally by, or under the direction of, healthcare professionals experienced in performing lumbar punctures.

For patients new to SPINRAZA: 2 loading doses followed by maintenance dosing

Initiate treatment with High Dose SPINRAZA as follows: Administer one 50 mg
loading dose followed by a second 50 mg dose 14 days later. Administer 28 mg
once every 4 months, starting 4 months after the last loading dose.

If transitioning from Low Dose Regimen, patients follow their existing schedule

Transition from Low Dose SPINRAZA as follows: Administer one 50 mg loading dose
at least 4 months, +/-14 days, after the last 12 mg maintenance dose, followed by a 28
mg maintenance dose every 4 months thereafter. Additional clinical benefit in patients who transition from Low Dose SPINRAZA to High
Dose SPINRAZA has not been established in a controlled study.

Guidance for administering High Dose SPINRAZA after a missed dose1

Conduct the following laboratory tests at baseline and prior to each dose of SPINRAZA and as clinically needed:

  • Platelet count
  • Prothrombin time; activated partial thromboplastin time
  • Quantitative spot urine protein testing

The NDC for
SPINRAZA 28 mg/5 mL
is 64406-036-011

The NDC for
SPINRAZA 50 mg/5 mL

is 64406-037-011

Learn about the dosing regimen options below

SEE SAFETY INFORMATION

Low Dose SPINRAZA for SMA patients1

The dosing schedule for Low Dose SPINRAZA is shown below.

SPINRAZA is administered intrathecally by, or under the direction of, healthcare professionals experienced in performing lumbar punctures.

Low Dose SPINRAZA is available to patients with 4 loading doses followed by maintenance dosing

Low Dose SPINRAZA is 12 mg/5 mL per administration. Treatment begins with 4 loading doses. The first 3 doses are administered at 14-day intervals. The fourth dose should be administered 30 days after the third dose. After the loading period, a dose should be administered once every 4 months.

Guidance for administering Low Dose SPINRAZA after a missed dose1

Conduct the following laboratory tests at baseline and prior to each dose of SPINRAZA and as clinically needed:

  • Platelet count
  • Prothrombin time; activated partial thromboplastin time
  • Quantitative spot urine protein testing

As part of intrathecal administration:

  • No daily administration
  • Medication is shipped directly to HCP. Patient is not responsible for storage
  • Option for patients with any bulbar status
  • Biogen Support Services can help patients coordinate logistics of treatment

Intrathecal injection is an option for many patients2-5

  • Consider sedation and ultrasound or other imaging techniques at the discretion of the healthcare provider1

CSF, cerebrospinal fluid; HCP, healthcare provider; SMA, spinal muscular atrophy.

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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.

As a courtesy, our full Prescribing Information is also available en Español. For prescribing decisions, please refer to official approved labeling.

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. Mercuri E, Darras BT, Chiriboga CA, et al; CHERISH Study Group. Nusinersen versus sham control in later-onset spinal muscular atrophy. N Engl J Med. 2018;378(7):625-635. doi:10.1056/NEJMoa1710504 4. Haché M, Swoboda KJ, Sethna N, et al. Intrathecal injections in children with spinal muscular atrophy: nusinersen clinical trial experience. J Child Neurol. 2016;31(7):899-906. doi:10.1177/0883073815627882 5. Stolte B, Totzeck A, Kizina K, et al. Feasibility and safety of intrathecal treatment with nusinersen in adult patients with spinal muscular atrophy. Ther Adv Neurol Disord. 2018;11:1-9. doi:10.1177/1756286418803246

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