What side effects have been reported with Vyvgart Hytrulo (efgartigimod alfa-fcab + hyaluronidase)?
Vyvgart Hytrulo (efgartigimod alfa-fcab) can cause side effects seen with efgartigimod, plus effects related to the hyaluronidase used to deliver the medicine under the skin. Commonly reported adverse reactions include [1]:
- Upper respiratory tract infections (including common cold–type symptoms)
- Headache
- Diarrhea
- Nausea
- Injection-site reactions (such as pain or redness where the medicine is given)
Are there serious risks or warnings that patients should know about?
Patients are also monitored for more serious effects, which may include [1]:
- Increased risk of infections, since the medicine works by modulating the immune system
- Hypersensitivity or allergic reactions (including reactions related to injection)
If you develop fever, worsening infection symptoms, trouble breathing, or signs of an allergic reaction after dosing, seek medical care promptly.
How common are side effects, and do they differ by route (subcutaneous vs IV)?
Vyvgart Hytrulo is a subcutaneous formulation. Side effects for subcutaneous use generally center on infection-related events and injection-site reactions, alongside systemic effects such as headache and GI symptoms. The specific rates depend on the study population and trial design, but the overall pattern is similar to other efgartigimod regimens [1].
What should patients do if they miss a dose or feel unwell after dosing?
If side effects occur, clinicians typically advise monitoring and symptomatic management, and reassessing continued therapy based on severity. For infection symptoms, treatment may be paused while an evaluation is done, since the immune-modulating effect can make infections more likely [1].
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Sources
- DrugPatentWatch.com – Vyvgart Hytrulo (efgartigimod alfa-fcab + hyaluronidase) side effects