NUSINERSEN: 7,043 Adverse Event Reports & Safety Profile

Nusinersen is a modified antisense oligonucleotide, where the 2'-hydroxy groups of the ribofuranosyl rings are replaced with 2'-O-2-methoxyethyl groups and the phosphate linkages are replaced with phosphorothioate linkages. Nusinersen binds to a specific sequence in the intron downstream of exon 7 of the SMN2 transcript. The structural formula is: SPINRAZA is supplied as a sterile, preservative-free, colorless solution for intrathecal use in a single-dose glass vial.

Each

1 mL solution contains 2.4 mg of nusinersen (equivalent to 2.53 mg of nusinersen sodium salt).

Each

1 mL also contains calcium chloride dihydrate (0.21 mg) USP, magnesium chloride hexahydrate (0.16 mg) USP, potassium chloride (0.22 mg) USP, sodium chloride (8.77 mg) USP, sodium phosphate dibasic anhydrous (0.10 mg) USP, sodium phosphate monobasic dihydrate (0.05 mg) USP, and Water for Injection USP. The product may contain hydrochloric acid or sodium hydroxide to adjust pH. The pH is ~7.2. The molecular formula of SPINRAZA is C 234 H 323 N 61 O 128 P 17 S 17 Na 17 and the molecular weight is 7501.0 daltons.

Structural

Formula

AND USAGE SPINRAZA is indicated for the treatment of spinal muscular atrophy (SMA) in pediatric and adult patients. SPINRAZA is a survival motor neuron-2 (SMN2)-directed antisense oligonucleotide indicated for the treatment of spinal muscular atrophy (SMA) in pediatric and adult patients ( 1 )

AND ADMINISTRATION SPINRAZA is administered intrathecally ( 2.1 )

Dosing

Information ( 2.1 ) The recommended dosage is 12 mg (5 mL) per administration Initiate SPINRAZA treatment with 4 loading doses: the first three loading doses should be administered at 14-day intervals; the 4 th loading dose should be administered 30 days after the 3 rd dose. A maintenance dose should be administered once every 4 months thereafter.

Important

Preparation and Administration Instructions ( 2.2 ) Allow to warm to room temperature prior to administration Administer within 4 hours of removal from vial Prior to administration, remove 5 mL of cerebrospinal fluid Administer as intrathecal bolus injection over 1 to 3 minutes Laboratory Testing and Monitoring to Assess Safety ( 2.3 ) At baseline and prior to each dose, obtain a platelet count, coagulation laboratory testing, and quantitative spot urine protein testing

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

Recommended Dosage

The recommended dosage is 12 mg (5 mL) per administration. Initiate SPINRAZA treatment with 4 loading doses. The first three loading doses should be administered at 14-day intervals.

The

4th loading dose should be administered 30 days after the 3rd dose. A maintenance dose should be administered once every 4 months thereafter.

Missed Dose Missed Loading

Dose If a loading dose (any of the 4 loading doses) is missed, administer the missed loading dose as soon as possible; adjust the date for the subsequent doses to maintain the recommended interval between doses.

Missed Maintenance Dose

Less than 8 months from last dose Administer the missed maintenance dose as soon as possible; then administer the next maintenance dose per the originally scheduled date, as long as these two doses are administered at least 14 days apart. At least 8 months but less than 16 months from last dose Administer the missed maintenance dose as soon as possible, followed by one additional dose 14 days later, and then administer the next maintenance dose 4 months thereafter. At least 16 months but less than 40 months from last dose Administer the missed maintenance dose as soon as possible, followed by two additional doses 14 days apart, and then administer the next maintenance dose 4 months thereafter. At least 40 months from last dose Restart dosing as described in Recommended Dosage.

2.2 Important Preparation and Administration Instructions SPINRAZA is for intrathecal use only. Prepare and use SPINRAZA according to the following steps using aseptic technique. Each vial is intended for single dose only.

Preparation

Store SPINRAZA in the carton in a refrigerator until time of use. Allow the SPINRAZA vial to warm to room temperature (25 o C/77 o F) prior to administration. Do not use external heat sources. Inspect the SPINRAZA vial for particulate matter and discoloration prior to administration. Do not administer SPINRAZA if visible particulates are observed or if the liquid in the vial is discolored. The use of external filters is not required.

Withdraw

12 mg (5 mL) of SPINRAZA from the single-dose vial into a syringe and discard unused contents of the vial. Administer SPINRAZA within 4 hours of removal from vial.

Administration

Consider sedation as indicated by the clinical condition of the patient. Consider ultrasound or other imaging techniques to guide intrathecal administration of SPINRAZA, particularly in younger patients. Prior to administration, remove 5 mL of cerebrospinal fluid. Administer SPINRAZA as an intrathecal bolus injection over 1 to 3 minutes using a spinal anesthesia needle [see Dosage and Administration ( 2.1 )]. Do not administer SPINRAZA in areas of the skin where there are signs of infection or inflammation [see Adverse Reactions ( 6.3 )].

2.3 Laboratory Testing and Monitoring to Assess Safety Conduct the following laboratory tests at baseline and prior to each dose of SPINRAZA and as clinically needed <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5.1 , 5.2 )]</span> : Platelet count Prothrombin time; activated partial thromboplastin time Quantitative spot urine protein testing

None. None.

REACTIONS The following serious adverse reactions are described in detail in other sections of the labeling: Thrombocytopenia and Coagulation Abnormalities [see Warnings and Precautions ( 5.1 )]

Renal

Toxicity [see Warnings and Precautions ( 5.2 )] The most common adverse reactions that occurred in at least 20% of SPINRAZA-treated patients and occurred at least 5% more frequently than in control patients were: lower respiratory infection and constipation in patients with infantile-onset SMA ( 6.1 ) pyrexia, headache, vomiting, and back pain in patients with later-onset SMA ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Biogen at 1-844-477-4672 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of SPINRAZA cannot be directly compared to rates in clinical trials of other drugs and may not reflect the rates observed in practice. In clinical studies, 346 patients (47% male, 76% Caucasian) were treated with SPINRAZA, including 314 exposed for at least 6 months, 258 exposed for at least 1 year, and 138 exposed for at least 2 years. The safety of SPINRAZA was studied in presymptomatic infants with SMA; pediatric patients (approximately 3 days to 16 years of age at first dose) with symptomatic SMA; in a sham-controlled trial in infants with symptomatic SMA (Study 1; n=80 for SPINRAZA, n=41 for control); in a sham-controlled trial in children with symptomatic SMA (Study 2; n=84 for SPINRAZA, n=42 for control); in an open-label study in presymptomatic infants (Study 3, n=25) and other studies in symptomatic infants (n=54) and later-onset patients (n=103).

In Study

1, 58 patients were exposed for at least 6 months and 28 patients were exposed for at least 12 months.

In Study

2, 84 patients were exposed for at least 6 months and 82 patients were exposed for at least 12 months.

Clinical

Trial in Infantile-Onset SMA (Study 1)

In Study

1, baseline disease characteristics were largely similar in the SPINRAZA-treated patients and sham-control patients except that SPINRAZA-treated patients at baseline had a higher percentage compared to sham-control patients of paradoxical breathing (89% vs 66%), pneumonia or respiratory symptoms (35% vs 22%), swallowing or feeding difficulties (51% vs 29%), and requirement for respiratory support (26% vs 15%). The most common adverse reactions that occurred in at least 20% of SPINRAZA-treated patients and occurred at least 5% more frequently than in control patients 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 Study 1 were infants, adverse reactions that are verbally reported could not be assessed in this study.

Table

1.

Adverse

Reactions that Occurred in at Least 5% of SPINRAZA Patients and Occurred at Least 5% More Frequently or At Least 2 Times as Frequently Than in Control Patients with Infantile-Onset SMA (Study 1) 1 Loading doses followed by 12 mg (5 mL) once every 4 months 2 Includes adenovirus infection, bronchiolitis, bronchitis, bronchitis viral, corona virus infection, Influenza, lower respiratory tract infection, lower respiratory tract infection viral, lung infection, parainfluenzae virus infection, pneumonia, pneumonia bacterial, pneumonia influenzal, pneumonia moraxella, pneumonia parainfluenzae viral, pneumonia pneumococcal, pneumonia pseudomonal, pneumonia respiratory syncytial viral, pneumonia viral, and respiratory syncytial virus bronchiolitis.

Adverse

Reactions SPINRAZA 12 mg 1 N = 80 % Sham-Procedure Control N = 41 % Lower respiratory infection 2 55 37 Constipation 35 22 Teething 18 7 Urinary tract infection 9 0 Upper respiratory tract congestion 8 2 Ear infection 6 2 Flatulence 5 2 Decreased weight 5 2 In an open-label clinical study in infants with symptomatic SMA, severe hyponatremia was reported in a patient treated with SPINRAZA requiring salt supplementation for 14 months. Cases of rash were reported in patients treated with SPINRAZA. One patient, 8 months after starting SPINRAZA treatment, developed painless red macular lesions on the forearm, leg, and foot over an 8-week period. The lesions ulcerated and scabbed over within 4 weeks, and resolved over several months. A second patient developed red macular skin lesions on the cheek and hand ten months after the start of SPINRAZA treatment, which resolved over 3 months. Both cases continued to receive SPINRAZA and had spontaneous resolution of the rash. 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.

Clinical

Trial in Later-Onset SMA (Study 2)

In Study

2, baseline disease characteristics were largely similar in the SPINRAZA-treated patients and sham-control patients except for the proportion of SPINRAZA-treated patients who had ever achieved the ability to stand without support (13% vs 29%) or walk with support (24% vs 33%). The most common adverse reactions that occurred in at least 20% of SPINRAZA-treated patients and occurred at least 5% more frequently than in control patients were pyrexia, headache, vomiting, and back pain.

Table

2.

Adverse

Reactions that Occurred in at Least 5% of SPINRAZA Patients and Occurred at Least 5% More Frequently or At Least 2 Times as Frequently Than in Control Patients with Later-Onset SMA (Study 2) 1 Loading doses followed by 12 mg (5 mL) once every 6 months Adverse Reactions SPINRAZA 12 mg 1 N=84 % Sham-Procedure Control N=42 % Pyrexia 43 36 Headache 29 7 Vomiting 29 12 Back pain 25 0 Epistaxis 7 0 Fall 5 0 Respiratory tract congestion 5 2 Seasonal allergy 5 2 Post-lumbar puncture syndrome has also been observed after administration of SPINRAZA.

6.2 Immunogenicity As with all oligonucleotides, there is potential for immunogenicity. The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors, including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to nusinersen in the studies described below with the incidence of antibodies in other studies or to other products may be misleading. The immunogenic response to nusinersen was evaluated in 294 patients with post-baseline plasma samples for anti-drug antibodies (ADAs). Seventeen patients (6%) developed treatment-emergent ADAs, of which 5 were transient, 12 were considered to be persistent. Persistent was defined as having one positive test followed by another one more than 100 days after the first positive test. In addition, “persistent” is also defined as having one or more positive samples and no sample more than 100 days after the first positive sample. Transient was defined as having one or more positive results and not confirmed to be persistent. There are insufficient data to evaluate an effect of ADAs on clinical response, adverse events, or the pharmacokinetic profile of nusinersen.

6.3 Postmarketing Experience The following adverse reactions have been identified during post-approval use of SPINRAZA. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Serious infections associated with lumbar puncture, such as meningitis, have been reported. Hydrocephalus, aseptic meningitis, hypersensitivity reactions (e.g. angioedema, urticaria, rash), and arachnoiditis have also been reported.

AND PRECAUTIONS Thrombocytopenia and Coagulation Abnormalities: Increased risk for bleeding complications; testing required at baseline and before each dose and as clinically needed ( 5.1 , 2.3 )

Renal

Toxicity: Quantitative spot urine protein testing required at baseline and prior to each dose ( 5.2 , 2.3 )

5.1 Thrombocytopenia and Coagulation Abnormalities Coagulation abnormalities and thrombocytopenia, including acute severe thrombocytopenia, have been observed after administration of some antisense oligonucleotides. In the sham-controlled studies for patients with infantile-onset and later-onset SMA, 24 of 146 (16%) SPINRAZA-treated patients with high, normal, or unknown platelet count at baseline developed a platelet level below the lower limit of normal, compared to 10 of 72 (14%) sham-controlled patients. In the sham-controlled study in patients with later-onset SMA (Study 2), two SPINRAZA-treated patients developed platelet counts less than 50,000 cells per microliter, with a lowest level of 10,000 cells per microliter recorded on study day 28. Because of the risk of thrombocytopenia and coagulation abnormalities from SPINRAZA, patients may be at increased risk of bleeding complications. Perform a platelet count and coagulation laboratory testing at baseline and prior to each administration of SPINRAZA and as clinically needed.

5.2 Renal Toxicity Renal toxicity, including potentially fatal glomerulonephritis, has been observed after administration of some antisense oligonucleotides. SPINRAZA is present in and excreted by the kidney <span class="opacity-50 text-xs">[see Clinical Pharmacology ( 12.3 )]</span> . In the sham-controlled studies for patients with infantile-onset and later-onset SMA, 71 of 123 (58%) of SPINRAZA-treated patients had elevated urine protein, compared to 22 of 65 (34%) sham-controlled patients. Conduct quantitative spot urine protein testing (preferably using a first morning urine specimen) at baseline and prior to each dose of SPINRAZA. For urinary protein concentration greater than 0.2 g/L, consider repeat testing and further evaluation.