[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Neuroprotective agents for ALS](https://durgical.com/en/pharmacology/classes/neuroprotective-agents-for-als/) › Tofersen

# Tofersen

## Neuroprotective agents for ALS?

Neuroprotective agents for ALS

Intrathecal antisense oligonucleotide for ALS caused by SOD1 mutations. It lowers SOD1 protein production; approval was based on a fall in neurofilament light.

Updated Nov 1, 2026

## Quick facts

**Group**
[Neuroprotective agents for ALS](https://durgical.com/en/pharmacology/classes/neuroprotective-agents-for-als/)

**Target**
SOD1 mRNA (superoxide dismutase 1)

**Used for**
Amyotrophic lateral sclerosis

**Key effects**
Pain · Fatigue · Joint and muscle pain

**Monitor**
Neurological symptoms after each dose

**ATC**
N07XX22

No doses: the clinician sets them by the current guideline.

On this page

- The basics Mechanism of action
- Indications
- Adverse effects
- Pharmacokinetics
- Memory aid

- Safety Contraindications
- Key interactions
- What is monitored
- Administration and safety
- Pregnancy and breastfeeding
- Nursing care

- Study Test yourself

- Connections Connections

## Mechanism of action

In SOD1-ALS, mutations in the superoxide dismutase 1 gene produce a harmful protein that builds up in motor neurons. Tofersen is an antisense oligonucleotide that targets SOD1 mRNA, reducing the synthesis of SOD1 protein. Treated patients had lower plasma neurofilament light, a blood marker of axonal injury, which is reasonably likely to predict clinical benefit; confirmatory trials are ongoing.

- Injected intrathecally into the cerebrospinal fluid
- Binds SOD1 mRNA in motor neurons
- Less mutant SOD1 protein is made
- Less axonal injury: plasma neurofilament light falls

## Indications

- Amyotrophic lateral sclerosis in adults with a mutation in the SOD1 gene (accelerated approval) [Amyotrophic lateral sclerosis →](https://durgical.com/en/conditions/amyotrophic-lateral-sclerosis/)

## Adverse effects

### Common

- Pain, including back pain after lumbar puncture
- Fatigue
- Joint and muscle pain
- Increased white cells in the cerebrospinal fluid

### Serious (rare, important)

- Signs of spinal cord or nerve-root inflammation: weakness, numbness, burning or tingling in the limbs, back or neck pain, loss of bowel or bladder control
- Signs of raised intracranial pressure: unusual, persistent headache, blurred or double vision, ringing in the ears
- Meningitis-like symptoms: fever, headache, nausea, sensitivity to light, stiff neck, confusion

## Contraindications

- Hypersensitivity to tofersen or to any component of the solution

## Key interactions

**Other medicines**
No clinically important interactions are listed in the patient information; every medicine and supplement is still reviewed before each dose.

## What is monitored

- Neurological symptoms after each dose (weakness, numbness, bladder or bowel changes)
- Headache and visual changes
- Signs of meningeal irritation
- Laboratory tests as scheduled by the treating team

## Administration and safety

- Given intrathecally by lumbar puncture by an experienced clinician, in an office or clinic.
- Loading doses come first, then maintenance doses at regular intervals; missed doses are rescheduled promptly.
- Genetic testing confirms the SOD1 mutation before treatment.

## Pregnancy and breastfeeding

Data are limited; pregnancy or breastfeeding is reported to the treating doctor.

## Nursing care

- After each lumbar puncture, watch for headache, back pain and new neurological symptoms.
- Teach the patient to report weakness, numbness, bladder or bowel changes, visual changes or fever with stiff neck at once.
- Support the patient and family with the genetic implications of SOD1-ALS.
- Record function and breathing to follow the disease.

## Pharmacokinetics

**Absorption**
Given intrathecally by lumbar puncture, by professionals experienced in the procedure.

## Memory aid

TOFERSEN «TOnes down the Faulty Enzyme RNA, SOD1»: an ASO that silences SOD1 messages.

## Test yourself

Think of the answer, then tap the question to see it.

## Which ALS patients are candidates for tofersen?

Adults with ALS associated with a mutation in the SOD1 gene.

## How does tofersen act?

It is an antisense oligonucleotide that targets SOD1 mRNA and reduces the synthesis of SOD1 protein.

## Which biomarker supported the accelerated approval of tofersen?

A reduction in plasma neurofilament light, a marker of axonal injury.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/tofersen/)

[More Pharmacology questions →](https://durgical.com/en/practice/?f=pharmacology)

## Connections

## Related drugs 3

- [Riluzole](https://durgical.com/en/pharmacology/riluzole/)
- [Edaravone](https://durgical.com/en/pharmacology/edaravone/)
- [Nusinersen](https://durgical.com/en/pharmacology/nusinersen/)

## Related conditions 1

- [Amyotrophic lateral sclerosis](https://durgical.com/en/conditions/amyotrophic-lateral-sclerosis/)

[← Back to the class: Neuroprotective agents for ALS](https://durgical.com/en/pharmacology/classes/neuroprotective-agents-for-als/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [Tofersen Injection: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a623024.html) (MedlinePlus (U.S. National Library of Medicine), 2023); [FDA approves treatment of amyotrophic lateral sclerosis associated with a mutation in the SOD1 gene](https://www.fda.gov/drugs/news-events-human-drugs/fda-approves-treatment-amyotrophic-lateral-sclerosis-associated-mutation-sod1-gene) (U.S. Food and Drug Administration, 2023); [Amyotrophic lateral sclerosis: MedlinePlus Genetics](https://medlineplus.gov/genetics/condition/amyotrophic-lateral-sclerosis/) (MedlinePlus Genetics (U.S. National Library of Medicine), 2016); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=N07XX22) (WHO Collaborating Centre for Drug Statistics Methodology, 2026).

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Representative model, for educational purposes only.

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Source: https://durgical.com/en/pharmacology/tofersen/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/tofersen/