By Counterforce Health Team —

Qalsody (Tofersen): A Targeted Therapy for ALS with SOD1 Mutation

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects nerve cells responsible for controlling voluntary muscles. It leads to muscle weakness, difficulty speaking, swallowing, and breathing, and currently has limited treatment options.

Qalsody® (tofersen) is a novel therapy designed for a specific form of ALS caused by mutations in the SOD1 gene. It is the first therapy targeting this genetic form of ALS, offering hope for patients with this rare mutation.

What Is Qalsody Used For?

Qalsody is approved for the treatment of adults with ALS who have a confirmed mutation in the SOD1 gene.

Its primary goal is to:

  • Reduce levels of toxic SOD1 protein in the nervous system
  • Slow the progression of disease associated with SOD1 mutations
  • Preserve muscle function and mobility for as long as possible

Because ALS is a progressive disease, Qalsody is most effective when started early in patients with the SOD1 mutation.

How Qalsody Works

Qalsody is an antisense oligonucleotide (ASO), a type of genetic therapy. Its mechanism of action includes:

  1. Targeting SOD1 mRNA: Qalsody binds to the messenger RNA that carries instructions to make SOD1 protein.
  2. Reducing SOD1 protein production: This decreases the levels of toxic SOD1 protein that can damage motor neurons.
  3. Protecting nerve cells: By reducing harmful protein accumulation, it helps preserve motor neuron function and slows ALS progression.

This targeted approach addresses the underlying genetic cause of ALS in patients with SOD1 mutations rather than just treating symptoms.

How Qalsody Is Administered

  • Form: Intrathecal injection (directly into cerebrospinal fluid via lumbar puncture)
  • Dosing schedule: Typically every 2 weeks initially, followed by a maintenance schedule as directed by a healthcare provider
  • Setting: Administered by a trained healthcare professional in a clinic or hospital

Due to the delivery method, patients may need monitoring during and after each injection to ensure safety.

Benefits of Qalsody

  • Disease-modifying therapy: Targets the root cause of SOD1-ALS
  • Slows disease progression: Can help preserve muscle function longer
  • Personalized medicine: Specifically designed for patients with SOD1 mutations
  • Support for motor neurons: Protects nerve cells from toxic protein buildup

Possible Side Effects

Common side effects include:

  • Headache
  • Back pain
  • Fever
  • Nausea or vomiting
  • Reactions at the injection site

Serious but less common side effects may include:

  • Inflammation of the nervous system (meningitis-like symptoms)
  • Changes in cerebrospinal fluid lab values
  • Allergic reactions

Healthcare providers monitor patients carefully for these reactions during treatment.

Precautions and Monitoring

  • Genetic confirmation: Qalsody is only for patients with confirmed SOD1 mutations.
  • Regular monitoring: Includes lab tests and neurological exams to track disease progression and treatment safety.
  • Patients with pre-existing neurological or spinal conditions should be evaluated before therapy.
  • Report any new symptoms such as severe headache, fever, or neck stiffness immediately.

The Bottom Line

Qalsody (tofersen) is a first-of-its-kind therapy for ALS caused by SOD1 mutations. By targeting the underlying genetic cause, it offers the potential to slow disease progression and preserve motor function in affected adults. While administration requires careful monitoring and intrathecal delivery, Qalsody represents a significant advancement in personalized ALS treatment.