Note: This document contains side effect information about efgartigimod alfa. Some dosage forms listed on this page may not apply to the brand name Vyvgart.
Applies to efgartigimod alfa: intravenous solution.
Serious side effects of Vyvgart
Along with its needed effects, efgartigimod alfa (the active ingredient contained in Vyvgart) 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 efgartigimod alfa:
More common
- Bladder pain
- bloody or cloudy urine
- cough
- difficult, burning, or painful urination
- difficulty in moving
- fever
- frequent urge to urinate
- joint pain
- lower back or side pain
- muscle aches, cramps, pain, or stiffness
- sneezing
- sore throat
- swollen joints
Incidence not known
- Difficulty in breathing or swallowing
- fast heartbeat
- large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- skin itching, rash, or redness
- swelling of the face, throat, or tongue
- trouble breathing
Other side effects of Vyvgart
Some side effects of efgartigimod alfa may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.
Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
- Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
- headache
For Healthcare Professionals
Applies to efgartigimod alfa: intravenous solution.
General
The most common adverse reactions reported have included respiratory tract infections, headaches, and urinary tract infections.[Ref]
Respiratory
Very common (10% or more): Respiratory tract infections (33%)
In clinical trials, 33% of patients treated with this drug experienced respiratory tract infections compared to 29% of placebo patients.
Nervous system
Very common (10% or more): Headache (32%; included migraine, procedural headache)
Common (1% to 10%): Paraesthesia (included oral hypoesthesia, hypoesthesia, hyperesthesia)
Immunologic
Very common (10% or more): Drug antibodies (20%)
Common (1% to 10%): Neutralizing antibodies
Hematologic
Very common (10% or more): Below normal WBC counts (12%), below normal lymphocytes (28%), and below normal neutrophils (13%)
Below normal levels of WBCs, lymphocytes, and neutrophils were observed in patients treated with this drug (12%, 28%, and 13%, respectively) compared with placebo (5%, 19%, and 6%, respectively).
Genitourinary
Very common (10% or more): Urinary tract infections (UTI; 10%)
In clinical trials, 10% of patients treated with this drug experienced UTI compared to 5% of placebo patients.
Hypersensitivity
Frequency not reported: Hypersensitivity reactions including rash, angioedema, and dyspnea
Musculoskeletal
Common (1% to 10%): Myalgia
