Vyvgart (efgartigimod alfa-fcab) and Vyvgart Hytrulo (efgartigimod alfa/hyaluronidase-qvfc) are prescription medicines for certain types of generalized myasthenia gravis (gMG). Both of these products contain the medicine efgartigimod alfa, which is a protein substance made in the lab for humans (monoclonal antibody). The FDA approved Vyvgart in 2021 for the treatment of gMG in adults who have antibodies against a protein called the acetylcholine receptor (AChR). Vyvgart Hytrulo was approved in 2023 to treat the same form of gMG as Vyvgart. Vyvgart Hytrulo is also approved for chronic inflammatory demyelinating polyneuropathy (CIDP). A health care provider injects Vyvgart into your vein (IV infusion) or Vyvgart Hytrulo under the skin (subcutaneous) at their office or in a clinic. You may also be taught how to give Vyvgart Hytrulo yourself as an injection under the skin. Vyvgart or Vyvgart Hytrulo are given once a week in four-week cycles.
How Do Vyvgart & Vyvgart Hytrulo Work in gMG?
gMG is an autoimmune disease where the immune system mistakenly damages the connections between your nerves and muscles. This weakens your muscles and affects how they work. In people with gMG, the immune system blocks a protein called AChR, which is important for connecting nerves and muscles. The immune system does this using a group of immune proteins (antibodies).
Vyvgart attaches to a part of these antibodies, called neonatal Fc receptors (FcRn), which protects them from being destroyed. This lowers the amount of the antibodies in the blood and helps restore the connection between nerves and muscles. Vyvgart Hytrulo contains the same medicine as Vyvgart (efgartigimod alfa) and works the same way to treat gMG. However, Vyvgart Hytrulo also contains hyaluronidase. Hyaluronidase helps the body absorb the medicine when it is given as an injection under the skin.
Is Vyvgart or Vyvgart Hytrulo Right for Me?
Vyvgart or Vyvgart Hytrulo may be the right choice for you if:
- You are an adult with gMG.
- You have antibodies for AChR.
Your doctor will test you for AChR antibodies and review your medical history to decide if Vyvgart or Vyvgart Hytrulo is right for you.
How Was Vyvgart Studied for Treating gMG?
One clinical study, the ADAPT trial, was done to look at the benefits and risks of Vyvgart in people with advanced gMG.
The main question the study wanted to answer was: How well does Vyvgart work to improve symptoms in people with gMG who have antibodies for AChR?
To learn this, the researchers measured the effect of Vyvgart using a test called the Myasthenia Gravis-Specific Activities of Daily Living scale (MG-ADL), which shows how gMG affects daily activities. A higher score means gMG has a bigger impact on those activities.
What medicines did the people in the study take?
People in the study were randomly selected to take either Vyvgart or a placebo. The placebo looked like Vyvgart but didn’t contain any medicine. Neither the people in the study nor the healthcare providers knew who received Vyvgart and who got the placebo.
Who was included in the study?
To take part in the study, people had to:
- Be at least 18 years old
- Have class 2 to 4 myasthenia gravis that affects the muscles all over the body
- Have a score of 5 or higher on the MG-ADL test
- Be on other medicines for myasthenia gravis for a period of time before the study
Who was excluded from the study?
People could not be in this study if they:
- Had gotten other medicines that affected their immune system within six months of the study
- Had hepatitis B or antibodies for hepatitis C or HIV
What was the study population?
- 167 people were in the study.
- 84 people got Vyvgart, and 83 people got the placebo.
- About 71% were female.
- Most of the people in the study (77%) had antibodies for AChR.
- The average age of the people in the study was 46 years (from 19 to 81 years).
- Among the people who got Vyvgart, about 82% were White, 11% Asian, 4% Black, and 4% Other.
How long was the study?
People got Vyvgart or the placebo for about 6.5 months (26 weeks).
What was the main benefit of Vyvgart?
Vyvgart was much more effective at improving gMG symptoms compared to the placebo. About 68% of the people who took Vyvgart could perform their daily activities better, compared to about 30% of those who got the placebo.
How was Vyvgart Hytrulo Studied for Treating gMG?
Vyvgart Hytrulo contains the same medicine as Vyvgart, but it is given as an injection under the skin (subcutaneous) over 20 to 90 seconds, while Vyvgart is given as an IV infusion over 1 hour. The study described above for Vyvgart was also used to show that Vyvgart Hytrulo is effective for treatment gMG.
Another study was done with Vyvgart Hytrulo to see if there was any difference in blood levels when the medicine was given under the skin as compared to giving it by IV infusion. This study found no meaningful differences in blood levels between Vyvgart Hytrulo and Vyvgart. The safety and efficacy of Vyvgart Hytrulo was generally similar to Vyvgart.
What Are the Serious Side Effects of Vyvgart and Vyvgart Hytrulo That I Should Be Aware Of?
Serious side effects that may happen when you get your Vyvgart infusion or Vyvgart Hytrulo injection are:
Allergic reactions (hypersensitivity reactions). You may have allergic reactions to Vyvgart or Vyvgart Hytrulo, like rashes, swelling under the skin, and shortness of breath. These reactions are usually mild and can happen within one hour to three weeks after a Vyvgart infusion or Vyvgart Hytrulo injection.
Some people have had serious allergic reactions, including trouble breathing or a drop in blood pressure that caused them to faint.
Infusion or Injection reactions. You may have reactions during or after your Vyvgart infusion or Vyvgart Hytrulo injection, including high blood pressure, chills, shivering, and pain in your chest, stomach, or back.
Vyvgart Hytrulo may cause a reaction where the needle went into your skin such as skin redness, rash, itching, bruising, pain, and hives. Most often these injection site reactions are mild to moderate, happen within about four hours of the injection, and need no treatment.
Contact your health care provider right away if you have symptoms of an allergic reaction or infusion or injection reaction when you are outside the clinic.
Infections. Vyvgart or Vyvgart Hytrulo may cause you to get more infections.
The most common side effects of Vyvgart or Vyvgart Hytrulo are:
Infections in your sinuses, throat, airways, or lungs (respiratory tract infections). If you have a fever, chills, cough, runny nose, sinus pain, or headache, drink plenty of fluids and get some rest. Your pharmacist may recommend nonprescription pain medicines, like acetaminophen, or cough and cold medicines. Avoid being around people who are sick, and stay away from crowded places, especially during cold and flu season. Wear a well-fitting mask in busy areas for added safety.
Headache. You may get headaches, including migraines. Your pharmacist may recommend nonprescription painkillers like ibuprofen or acetaminophen.
Tell your health care provider if you have a fever, chills, an ongoing cough, or a headache that won’t go away.
Bladder (urinary tract) infection. Drink plenty of water to help keep bladder infections away.
Tell your health care provider if you have bladder pain, blood in your urine, need to urinate frequently, or if you feel burning or pain when you urinate.
You may also feel muscle pain or have numbness or tingling in your body, including your mouth. These side effects are usually mild and will go away as your body gets used to Vyvgart or Vyvgart Hytrulo. Tell your health care provider if they don’t go away or become bothersome.
You can also report side effects to the drugmaker at 833-argx411 (833-274-9411), or to the FDA at 800-FDA-1088 (800-332-1088) or www.fda.gov/medwatch.
How Do I Know if Vyvgart or Vyvgart Hytrulo Is Working?
Your healthcare provider will regularly check how well Vyvgart or Vyvgart Hytrulo is working for your gMG by tracking your progress in performing your daily activities. They may ask you to write down your gMG symptoms after each infusion or injection and let them know if anything changes.
Do not stop your Vyvgart infusions or Vyvgart Hytrulo injections or change your schedule unless your health care provider tells you to do so.
How Do Other Medicines Interact With Vyvgart and Vyvgart Hytrulo?
Vyvgart or Vyvgart Hytrulo affects your immune system. Tell your health care providers and pharmacist about all the other prescription and nonprescription medicines, vitamins, supplements, and herbal products you take before starting Vyvgart or Vyvgart Hytrulo.
Vaccines:Tell your health care provider you are on Vyvgart or Vyvgart Hytrulo before getting any vaccines during a Vyvgart or Vyvgart Hytrulo cycle. Vyvgart or Vyvgart Hytrulo may affect how your body reacts to vaccines.
Non-live vaccines. It is not known if Vyvgart or Vyvgart Hytrulo makes non-live vaccines less effective. Some examples of these vaccines are tetanus, pneumonia, flu, hepatitis A, and polio.
Live vaccines. Getting live vaccines during a Vyvgart or Vyvgart Hytrulo cycle is not recommended. Some examples of live vaccines are measles, mumps, rubella, smallpox, chickenpox, and yellow fever.
How Can I Get Vyvgart or Vyvgart Hytrulo?
You will need a prescription from a neurologist, a health care provider who is an expert on the nervous system. Your neurologist will either offer you Vyvgart infusions or Vyvgart Hytrulo injections in their office or arrange for you to get Vyvgart or Vyvgart Hytrulo at a clinic. You or a caregiver may also be taught how to give the Vyvgart Hytrulo injections.
If you need support with payment for Vyvgart or Vyvgart Hytrulo, the drugmaker may be able to help you. Check out https://www.vyvgart.com/gmg/support-and-resources/cost-and-coverage to learn more about their copay program or to ask your questions about insurance. You can also contact the drugmaker at 833-Vyvgart (833-898-4278).
