Qalsody Side Effects

Generic name: tofersen

Medically reviewed by Drugs.com. Last updated on Aug 17, 2023.

Note: This document contains side effect information about tofersen. Some dosage forms listed on this page may not apply to the brand name Qalsody.

Applies to tofersen: intrathecal solution.

Serious side effects of Qalsody

Along with its needed effects, tofersen (the active ingredient contained in Qalsody) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking tofersen:

More common

Arm, leg, or back pain
difficulty in moving
joint pain or swelling
muscle aches, cramps, pains, or stiffness
nerve pain
unusual tiredness or weakness

Less common

Back numbness, tingling, or weakness
blurred vision
change in ability to see colors, especially blue or yellow
confusion
fever
headache
severe nausea or vomiting
stiff neck

For Healthcare Professionals

Applies to tofersen: intrathecal solution.

General

The most common adverse reactions occurring in 10% of patients or greater included pain, fatigue, arthralgia, increased cerebrospinal fluid white blood cells, and myalgia.^[Ref]

Immunologic

Very common (10% or more): Anti-drug antibodies (58.4%)^[Ref]

Musculoskeletal

Very common (10% or more): Arthralgia (14%), myalgia (14%), musculoskeletal stiffness (6%)^[Ref]

Nervous system

Very common (10% or more): Cerebrospinal fluid white blood cells increased or pleocytosis (14%)

Common (1% to 10%): Cerebrospinal fluid proteins increased (8%), neuralgia (6%), myelitis and radiculitis (4%), elevated intracranial pressure and/or papilledema (2.7%), aseptic meningitis (1.4%)^[Ref]