Enflonsia
Enflonsia (clesrovimab) is a monoclonal antibody that’s used to prevent respiratory syncytial virus (RSV) in babies who are born during or entering their first RSV season. It isn’t a vaccine. Your child will receive a single injection in the thigh muscle from a healthcare professional any time from birth up to 12 months old. This is usually done either right after birth or before RSV season starts. Common side effects include redness or swelling at the injection site and rash.
What is Enflonsia (clesrovimab)?
What is Enflonsia (clesrovimab) used for?
Prevention of respiratory syncytial virus (RSV) in newborns and infants (up to 12 months old) who are born during or entering their first RSV season
How Enflonsia (clesrovimab) works
Enflonsia (clesrovimab) is a type of monoclonal antibody. It works by attaching to a protein on the surface of the RSV virus called the F protein. When it attaches to the F protein, the medication prevents the virus from infecting healthy cells, which stops the infection from starting. And if your baby does get RSV, Enflonsia (clesrovimab) can help make the illness less severe.
Drug Facts
What are the side effects of Enflonsia (clesrovimab)?
Common Side Effects
- Redness at the injection site (4%)
- Swelling at the injection site (3%)
- Rash (2%)
Other Side Effects
- Diarrhea
- Decreased appetite
- Sleepiness
- Irritability
- Fever
Serious Side Effects
- Severe allergic reaction: Swelling of the face or throat, hives, itching
Source: DailyMed
The following side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
- Pain, redness, or irritation at injection site
- Skin rash
Pros and cons of Enflonsia (clesrovimab)
Pros
One-time injection into your baby’s thigh
Can be given at the same time as other vaccines
Dose is the same regardless of weight
It starts working right away to protect your baby and lasts for about 5 months
Cons
Must be given by a healthcare professional
Only FDA approved for children 12 months and younger
Injection can be uncomfortable
Risk of severe allergic reaction
Pharmacist tips for Enflonsia (clesrovimab)
Enflonsia (clesrovimab) is given as a one-time dose by a healthcare professional at birth or at the beginning of RSV season. It’s typically injected into the muscle of your baby’s thigh.
Enflonsia (clesrovimab) isn’t a vaccine. It is a lab-made antibody that gives babies immediate protection from RSV during their first RSV season.
Even though Enflonsia (clesrovimab) can lower your baby’s risk of getting RSV, they could still get sick from RSV. Pay attention to any symptoms of RSV in your baby such as severe congestion, runny nose, or a low-grade fever.
If your infant has heart surgery during RSV season, talk with your baby’s pediatrician, as they may need a second dose of Enflonsia (clesrovimab).
Your baby may also get other vaccines at the same time as Enflonsia (clesrovimab). Check with their pediatrician if you have questions about your baby getting this medication along with routine vaccines.
Reactions to Enflonsia (clesrovimab) are typically mild. If your baby experiences any redness or swelling around the injection site, contact their pediatrician. These side effects can happen up to 5 days after the injection.
Enflonsia (clesrovimab) can also cause a rash on your baby’s body, typically seen up to 14 days after the injection. If your baby shows any symptoms of a rash, contact their pediatrician.
Enflonsia (clesrovimab) can cause severe allergic reactions. Seek medical attention if your infant has any swelling of the lips, tongue, or throat or trouble breathing as these can be life-threatening.
Frequently asked questions about Enflonsia (clesrovimab)
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What are the risks and warnings for Enflonsia (clesrovimab)?
Enflonsia (clesrovimab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Severe Allergic Reactions
Enflonsia (clesrovimab) can cause severe allergic reactions like anaphylaxis. Anaphylaxis is a life-threatening reaction that causes swelling of the lips, tongue, or throat that can lead to trouble breathing. If your infant develops any symptoms of anaphylaxis after receiving the injection, seek medical help right away.
Enflonsia (clesrovimab) dosage forms
Typical dosing for Enflonsia (clesrovimab)
The typical dose is 105 mg injected once into your baby’s thigh muscle by a healthcare professional.
What are alternatives to Enflonsia (clesrovimab)?
Prevention of respiratory syncytial virus (RSV) in newborns and infants (up to 12 months old) who are born during or entering their first RSV season
Babies born premature and are 6 months or younger at the start of RSV season
Children diagnosed with bronchopulmonary dysplasia (BPD) within the last 6 months, and are 2 years or younger at the start of RSV season
Children with congenital heart disease (CHD) and are 2 years or younger at the start of RSV season
Prevention of respiratory syncytial virus (RSV) in young children of certain ages
Enflonsia (clesrovimab) images
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