Vyvgart Hytrulo (efgartigimod alfa/hyaluronidase-qvfc) is a prescription medicine that is used to treat certain muscle and nerve conditions. It is a combination of two medicines, efgartigimod alfa and hyaluronidase. Efgartigimod alfa is a protein, specifically a human immunoglobulin G (IgG) antibody fragment. Hyaluronidase is an enzyme that helps the body absorb and distribute efgartigimod alfa throughout the body.
Vyvgart Hytrulo is FDA-approved for the treatment of chronic inflammatory demyelinating polyneuropathy (CIDP). It is given once a week as a shot under the skin. Vyvgart Hytrulo may also be used to treat generalized myasthenia gravis (gMG) in adults who have antibodies against a protein called the acetylcholine receptor (AChR).
What Is CIDP and How does Vyvgart Hytrulo Work to Treat It?
The exact cause of CIDP is not known, but it is thought to be an autoimmune disease in which the immune system mistakenly damages your nerves. This weakens your muscles and affects how they work. Symptoms include tiredness, areas of numbness and pain, slowed reflexes, and weakness in your arms and legs. Early treatment is important because the sooner you start treatment, the better your chances of a complete recovery.
Vyvgart Hytrulo works by binding to certain receptors in the body, called neonatal Fc receptors (FcRn). Binding to these receptors helps lower the amount of IgG in the blood. This helps slow down the worsening of weakness in the arms and legs.
How Do I Use Vyvgart Hytrulo?
Vyvgart Hytrulo is a shot that is given under the skin (subcutaneous) once a week. It may be given by a health care provider or you or a caregiver may be taught how to give the injections at home. You should be monitored for at least 30 minutes after the infusion for signs of an allergic reaction.
Keep all appointments for your shot. If you miss a dose of Vyvgart Hytrulo, you can get it up to three days after the scheduled time. Then, resume your regular schedule.
How Was Vyvgart Hytrulo Studied for Treatment of CIDP?
The ADHERE trial was a two-stage clinical study that looked at the safety, efficacy, and tolerability of Vyvgart Hytrulo in adults with CIDP. The goal of this study was to see if Vyvgart Hytrulo worked better than a placebo (containing no medicine) at reducing the risk of relapse (return of CIDP disease symptoms after they got better) in people with CIDP who responded to treatment.
The main objective of the first part of the study (Stage A) was to find the percentage of people who responded to treatment with Vyvgart Hytrulo when it was given once per week for 12 weeks.
The main objective of the next part of the study (Stage B) was to find out the length of time that arm and leg function was maintained without getting worse for people taking Vyvgart Hytrulo, compared to a placebo.
The researchers measured the effect of Vyvgart Hytrulo on disease improvement using multiple CIDP scales. The main scale used the adjusted Inflammatory Neuropathy Cause and Treatment (aINCAT) score to measure arm and leg function. It is a score from 0 to 10; a higher score means there is more disability in the arms and legs. Other tests used to measure symptoms included grip strength and the I-RODS score, which is used to measure how well you can perform daily activities such as walking, showering, and dressing.
What medicines did the people in the study take?
After a run-in period, during which people who were taking other medicines for CIDP stopped treatment for up to 12 weeks, everyone in the study used Vyvgart Hytrulo once per week for 12 weeks (Stage A). People who saw improvement in their CIDP symptoms continued to the next part of the study (Stage B).
In Stage B, people were randomly selected to take either Vyvgart Hytrulo or a placebo once per week for up to 48 weeks. The placebo looked like Vyvgart Hytrulo but did not contain any medicine. Neither the people in the study nor the doctors knew who received Vyvgart Hytrulo 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 progressing or relapsing forms of CIDP
- Have a CIDP Disease Activity Status (CDAS) score of at least 2, indicating active CIDP or disease that has been in remission (without symptoms) for less than five years
- Have an Inflammatory Neuropathy Cause and Treatment (INCAT) score of at least 2, which implies moderate arm and/or leg disability
- Be taking other medicines for CIDP such as corticosteroids, intravenous immunoglobulin (IVIg) or subcutaneous immunoglobulin (SCIg), or both, and be willing to discontinue treatment; or be off treatment
- Have a negative pregnancy test and (for people who can get pregnant) be using highly effective birth control treatment
Who was excluded from the study?
People could not be in this study if they had:
- Certain subtypes of CIDP
- Nerve problems due to other causes
- Lower than normal IgG blood levels
- Current or past history of alcohol, drug, or medication misuse
- Severe psychiatric disorders
- Received other medicines or treatments that affected their immune system within six months of the study
- Active or long-term infections, such as hepatitis B or antibodies for hepatitis C or HIV
- Pregnancy or were breastfeeding
- History of certain types cancer
What was the study population?
- There were 342 people in Stage A. Of these, 221 people (65%) had improvement in their disease and entered Stage B of the study.
- In Stage B, 111 people got Vyvgart Hytrulo, and 110 people got the placebo.
- About 65% were male.
- The average time since diagnosis of CIDP was 2.2 years
- The average age of the people in the study was 55 years.
- Among the people who got Vyvgart Hytrulo, about 66% were White, 30% Asian, 1% Black, and 2% other.
How long was the study?
People got Vyvgart Hytrulo or the placebo for about 12 months (48 weeks).
What was the main benefit of Vyvgart Hytrulo?
Vyvgart Hytrulo was better at maintaining the level of arm and leg function longer, compared to the placebo. The risk of CIDP relapse (return of disease symptoms after they got better) was 61% lower for people who took Vyvgart Hytrulo, compared to the placebo.
Your results may differ from what was seen in clinical studies.
How Long Does It Take to Work?
If Vyvgart Hytrulo is working, your symptoms will start to improve over the first few months of treatment. Do not stop your shots or change your schedule unless your health care provider tells you to do so.
What Are the Serious Side Effects, and How Can I Manage Them?
Allergic reactions (hypersensitivity reactions). You may have allergic reactions to Vyvgart Hytrulo, like rashes, swelling under the skin, and shortness of breath. These reactions are usually mild or moderate and can happen within one hour to three weeks after a Vyvgart Hytrulo shot.
Some people have had serious allergic reactions, including trouble breathing or a drop in blood pressure that caused them to faint. These reactions can happen during or after treatment, and your health care provider may need to pause or stop treatment if this happens.
Infusion reactions. You may have reactions during or after your Vyvgart Hytrulo shot, including high blood pressure, chills, shivering, and pain in your chest, stomach, or back. These usually happen during or within an hour of the shot.
You, a caregiver, or your health care provider should watch for signs of an allergic reaction or an infusion reaction during the shot and for at least 30 minutes afterward. A health care provider will treat any symptoms or stop the infusion if needed.
Contact your health care provider right away if you have symptoms of an allergic reaction or infusion reaction when you are outside the clinic.
What Are the Possible Side Effects, and How Can I Manage Them?
Injection site reaction. One of the most common side effects of Vyvgart Hytrulo is an injection site reaction – a reaction where the needle went into your skin. Injection site reactions include skin redness, rash, itching, bruising, pain, and hives. Most often, these reactions are mild to moderate, happen within about 24 hours of the shot, and usually need no treatment.
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 doctor 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.
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 often, or if you feel burning or pain when you urinate.
If you have an infection, you may need to delay your dose of Vyvgart Hytrulo until the infection has cleared up. Tell your health care provider if you have a fever, chills, an ongoing cough, or other signs of an infection.
Headache. You may get headaches, including migraines. Your doctor may recommend nonprescription painkillers like acetaminophen or ibuprofen.
You may also feel muscle pain or have a tingling feeling in your body, including your mouth. These side effects are usually mild and will go away as your body gets used to Vyvgart Hytrulo. Tell your health care provider if they don’t go away or become bothersome.
These are not all the possible side effects. Talk with your health care provider if you are having symptoms that bother you. If you go through anything that you think may be caused by Vyvgart Hytrulo, you can also report side effects to the FDA at 800-FDA-1088 (800-332-1088).
Is There Any Cost Assistance Available?
There is a cost savings and support program from the drugmaker that may help you afford Vyvgart Hytrulo. Your health care provider will help you to get started with this program. For questions or more information, you can contact the drugmaker at 833-898-2437 or visit the My Vyvgart Path copay savings program.
