Kesimpta (ofatumumab) is an injectable medication for adults with relapsing forms of multiple sclerosis (MS). It works as a monoclonal antibody to help lessen MS flare-ups that come and go. Kesimpta (ofatumumab) is injected under the skin. You can use the Kesimpta prefilled syringes or Sensoready Pens to inject. After the first 3 weekly injections, you inject the medication once a month. Some common side effects include a higher risk of infections, pain or swelling at the injection site, and headache.
Relapsing forms of multiple sclerosis (MS), including relapsing-remitting MS, clinically isolated syndrome, and secondary progressive MS
Kesimpta (ofatumumab) is a monoclonal antibody. It's not exactly known how the medication works to help with MS.
But researchers think it attaches to a protein called CD20 found on immune cells in the body. It destroys these immune cells so they can't attack the coverings on your nerve cells by mistake. This might help relieve symptoms of MS.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Injections are once a month (after the first 3 injections)
Can inject at home after you're trained
Comes as prefilled syringes and Sensoready Pens
Can be kept at room temperature for up to 7 days
Must give as an injection under the skin
Raises your risk of infections
Not recommended for people who are pregnant
Put a reminder on your calendar for your Kesimpta (ofatumumab) injections. This helps you stay on track with your treatment. Inject the medication once a week for 3 weeks. Skip a week. Then, inject the medication once a month.
If you miss a dose of Kesimpta (ofatumumab), inject the medication as soon as you remember. Afterwards, continue with your usual dosing schedule.
After you inject Kesimpta (ofatumumab), the area might get red, itchy, swollen, or sore. These reactions happen within hours after the injection. They're usually mild and go away in a couple days. You can hold an ice pack wrapped in a towel over the area for about 10 minutes if you need relief. Talk to your care team if you need more help, if these reactions get worse over time, or if they don't go away.
Call your care team if you think you've gotten sick while taking Kesimpta (ofatumumab). Look for signs like a fever, chills, a cough that doesn't go away, or pain when you urinate. Your care team can see if you need to get treated for the infection. They might tell you to wait until you're better before your next injection.
Before getting any vaccines, tell the healthcare professional that you're taking Kesimpta (ofatumumab). They can help make sure the vaccine is safe for you. You shouldn't get live vaccines while taking this medication. We don't know if Kesimpta (ofatumumab) can make you more likely to get sick from a live vaccine. Examples of live vaccines are MMR (mumps, measles, and rubella vaccine) and FluMist (nasal spray flu vaccine).
If you can get pregnant, use birth control while taking Kesimpta (ofatumumab) and for at least 6 months after your last injection. There's a chance that the medication could harm an unborn baby. Let your prescriber know if you become pregnant while taking Kesimpta (ofatumumab).
How to use Kesimpta (ofatumumab):
Your first injection of Kesimpta (ofatumumab) will be given at your prescriber's office. Your care team will make sure you can inject the medication properly before they let you do it on your own at home. They'll also watch for reactions like headache, fever, muscle aches, and chills. These reactions are most common within a day of your first injection.
Follow the instructions on how to use and inject Kesimpta (ofatumumab) with the prefilled syringe or Sensoready Pen. Ask your care team or pharmacist if you have any questions or if you're not sure.
How to store Kesimpta (ofatumumab): Store the medication in the refrigerator, but don't let it freeze. If needed, you can keep it at room temperature (up to 86ºF) for up to 7 days before you need to throw it away. You can put unused Kesimpta (ofatumumab) back in the fridge but it's only good for another 7 days. Always keep the medication in the original package to protect it from light.
When it's time for your Kesimpta (ofatumumab) injection: Take the medication out of the refrigerator and lay it on a flat surface. Let it warm up to room temperature for 15 to 30 minutes. Don't try to warm up the medication any other way, like with a microwave or under hot water; you might damage it. Always check that the liquid is clear or slightly brownish-yellow. If it's very cloudy, discolored, or has many particles, don't use it and get a new syringe or pen.
Where to inject Kesimpta (ofatumumab): Inject the medication under the skin of your lower stomach (2 inches away from the belly button). You can also inject into the front of your thighs (preferred for the pen). Or, someone else can help inject it into your outer upper arm. Choose a different spot to inject into for each injection. Don't inject into skin with moles, scars, or stretch marks. Also avoid tender, bruised, red, scaly, or hard skin. This helps lower the risk of skin damage or irritation.
How to inject with the Kesimpta SensoReady Pen: Use the pen within 5 minutes after taking off the cap (don't recap it). Hold and press the pen 90 degrees straight against the injection area. You'll hear a click when the injection starts and another click when it's almost done. Keep holding the pen against your skin until the window on it turns green all the way. Then, take the pen off your skin.
How to inject with the Kesimpta prefilled syringe: Carefully take off the needle cap from the syringe. With one hand, pinch the skin at the injection site. With your other hand, insert the needle all the way into the skin at a 45-degree angle. Then, use the finger grips to hold the syringe and slowly press the plunger all the way down. Keep pressing the plunger down and hold the syringe in place for 5 seconds. Then, slowly release the plunger until the needle gets covered by the shield.
How to throw away Kesimpta (ofatumumab) after each injection: Throw away used syringes and pens in a sharps container. You can also use something made of heavy-duty plastic, like a laundry detergent bottle. This helps keep you and others safe from getting hurt from needles. Don't throw them away in your trash can. Ask your pharmacist to learn more about how to get rid of your sharps.
Kesimpta (ofatumumab) 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.
Risk factors: Active, chronic (long-term), or recurrent infection | Other medical conditions that raise your risk of infection | Taking medications that weaken your immune system
Kesimpta (ofatumumab) can make it harder for your body to fight germs. This can raise your risk of getting bacterial, viral, or fungal infections. These infections can sometimes be serious or life-threatening.
Before you start Kesimpta (ofatumumab), talk to your prescriber about your medical history. They will check to see if you have hepatitis B. People with this infection have had serious problems while taking Kesimpta (ofatumumab). Your prescriber can check that this medication is safe for you.
Also let your care team know about all the medications you take. It's important to check if you take other medications that can make your immune system weaker. This can raise your risk of infections even higher.
Upper respiratory infections and urinary tract infections are common with Kesimpta (ofatumumab). Call your care team if you think you have an infection. Watch for a fever, chills, a cough, trouble breathing, weakness, and pain when you urinate. If you get sick, your prescriber might tell you to wait until you're better before you continue with your injections.
The Kesimpta (ofatumumab) injection can cause reactions like fever, headache, muscle pain, and chills. Other reactions are itchiness, throat irritation, trouble breathing, dizziness, and fast heart rate. They usually happen within a day of your first injection. But they can also happen after later ones.
Sometimes, these reactions are hard to tell apart from a real allergic reaction. To keep you safe, your care team will help you with your first injection at the medical office or clinic. This is so you can get help fast if the reaction is serious.
If you have any of these symptoms at home, get medical help right away.
Kesimpta (ofatumumab) can lower the levels of certain immunoglobulins (antibodies) in your body. Your prescriber will check your antibody levels with blood tests before and during treatment. They'll keep checking even after you stop until your levels are back to normal. If your antibody levels are too low, immunoglobulin infusions might help bring them up. Your care team can help decide what the next steps are if this happens.
Animal studies show that Kesimpta (ofatumumab) can harm an unborn baby if given during pregnancy. It also has potential to make antibodies not work as well in newborns.
If you can become pregnant, use birth control while using Kesimpta (ofatumumab). Continue birth control for at least 6 months after your last dose of Kesimpta (ofatumumab). If you're pregnant or planning to be, ask your prescriber about safer options for you and your baby. Tell your prescriber right away if you get pregnant.
The typical starting dose is 20 mg injected under the skin once a week for 3 weeks.
Then starting from week 4, the typical maintenance dose is 20 mg injected under the skin once a month.
Inject Kesimpta (ofatumumab) under the skin of your lower stomach or front of your thigh. Someone can also help inject it into your outer upper arm.
Active hepatitis B infection
Allergy to ofatumumab
Relapsing forms of multiple sclerosis (MS), including relapsing-remitting MS, clinically isolated syndrome, and secondary progressive MS
Relapsing forms of multiple sclerosis
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