Generic name: tofersen is the generic name.
Dosage form: Intrathecal injection (100 mg/15 mL) is the way the drug is given.
Drug class: Agents that affect the central nerve system in various ways

What’s Qalsody?

Qalsody (tofersen) is a prescription medicine used to treat amyotrophic lateral sclerosis (ALS) in people with a specific genetic mutation in the superoxide dismutase 1 (SOD1) gene. Qalsody is the first treatment cleared by the FDA that slows the progression of ALS by focusing on a genetic cause of the disease. Qalsody works by lowering the amount of SOD1 protein, which is a toxic protein that hurts motor nerves and causes ALS symptoms.

Patients with ALS who have a mutation in the SOD1 gene (SOD1-ALS) make a toxic misfolded form of the SOD1 protein that harms the motor neurons. This causes muscle weakness, loss of function, and eventually death. Qalsody is an antisense oligonucleotide (ASO), which works by binding to SOD1 mRNA to reduce the amount of the toxic SOD1 protein that is made. This may help slow the development of ALS.


Serious side effects can happen when you take Qalsody. Call your doctor right away if you:

Patients who take Qalsody can get myelitis, which is an inflammation of the spinal cord, or radiculitis, which is a swelling of the nerve roots. Talk to your doctor about the signs of myelitis or radiculitis to learn more about them. Qalsody treatment may need to be stopped or stopped for a while.

When Qalsody is used to treat a patient, the optic nerve can swell (this is called papilledema) and the pressure inside the brain can rise (this is called elevated intracranial pressure).  Talk to your doctor about what signs you might have if you have papilledema or high intracranial pressure.

Aseptic meningitis is an inflammation of the linings of the brain that can happen in people who are taking Qalsody. Talk to your doctor to find out more about the signs and symptoms of aseptic meningitis.

What should I tell my doctor about Qalsody before I take it?

Before you take this medicine, you should tell your doctor if you are pregnant or want to get pregnant, or if you are nursing or want to start breastfeeding.

How do you give Qalsody?

 With a lumbar puncture, Qalsody is given intrathecally, which means that it is injected into the spinal canal.

Information dosage

The loading dose is 100 mg injected into the spine every 14 days for three doses.

The maintenance dose is 100 mg injected into the thigh every 28 days.

Comments: Think about putting the patient to sleep or using imaging methods to make giving this drug easier.

• Take 10 mL of cerebrospinal fluid before giving this medicine. Then, use a lumbar puncture needle to give Qalsody as an intrathecal bolus shot over 1 to 3 minutes.

• If the second loading dose is missed, it should be given as soon as possible. The third loading dose should be given 14 days after the second one.

• If you forget to give the third loading dose or a maintenance dose, give it as soon as you can. The next dose should be given 28 days later.

Use: To treat people with amyotrophic lateral sclerosis whose superoxide dismutase 1 gene has been changed. Continued approval for this indication may depend on the results of one or more confirmatory trials that show the clinical effect.

Dosage form: Injection 100 mg/15 mL solution (6.7 mg/mL) in a single-dose bottle with no preservatives.

What side affects does Qalsody have?

Common Qalsody side effects include pain in the back, arms, or legs, feeling tired, and pain in the muscles and joints.

• The number of white blood cells in the cerebrospinal fluid (CSF) has gone up.

Less Myelitis and radiculitis are two common but dangerous side effects (see the warnings above).

• Papilledema and high pressure inside the head (see above for signs).

• aseptic meningitis (see above for advice)


• Keep in the fridge between 2°C and 8°C (36°F and 46°F).

Keep in the original box to keep out light. Don’t freeze.

• Biogen MA Inc. in Cambridge, MA 02142.

For more details

Talk to your doctor or other healthcare source to make sure that the information on this page applies to your situation.

Medical Disclaimer

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