How Long Does Kesimpta Take to Work? Plus, 4 More Pharmacist-Backed Tips for Receiving It

Multiple sclerosis (MS) is a health condition where your immune system mistakenly attacks cells in your brain and spinal cord. It’s a chronic condition, but it’s become more and more treatable. Some MS treatments work by gradually modifying your immune system, while others treat symptoms during MS relapses.

Disease modifying therapy (DMT) medications are a mainstay of maintenance MS treatment. There are over 20 different DMTs that can be treatment options for MS, and Kesimpta (ofatumumab) is one of them. It’s FDA approved to treat relapsing forms of MS.

However, you may not notice Kesmipta’s effects right away. DMTs such as Kesimpta help manage relapses and damage from MS, but it takes time. Here, we’ll review how long it takes Kesimpta to work, how to use it, and what benefits you can expect.

1. It takes some time for Kesimpta to work

Kesimpta can take a few weeks to kick in and treat your MS.

Why the delay? B cells, a type of immune system cell, go rogue and cause nerve damage in MS. Kesimpta is thought to work by indirectly destroying B cells in specific parts of your body. Most people respond to Kesimpta within 2 weeks, but it may potentially take up to 12 weeks (up to 3 months) to bring your B cells down to low levels.

Onset time in clinical studies

In two clinical studies that contributed to Kesimpta’s FDA approval, Kesimpta was compared to a different MS medication, called Aubagio (teriflunomide). People receiving Kesimpta generally experienced fewer relapses and slowed disability progression compared to Aubagio. People that received Kesimpta also had fewer active lesions.

After 3 months of treatment, significantly fewer people receiving Kesimpta experienced disability progression compared to people taking Aubagio.

Some people with muscle weakness, eye problems, and other MS-related issues also saw improvements in their symptoms in these studies. However, it’s difficult to predict exactly when and in whom these improvements will happen.

2. You can inject Kesimpta yourself

Kesimpta comes in two different dosage forms: a Sensoready Pen and a pre-filled syringe. You’ll initially administer Kesimpta to yourself using either device once a week for 3 weeks. Then, you’ll inject yourself every 4 weeks (1 month) from that point forward.

Here, we’ll review some important tips and tricks for administering this under-the-skin medication.

Good to know: Don’t feel like you need to know everything about Kesimpta injections right away. Your healthcare professional (HCP) will walk you through your first Kesimpta injection so you’ll feel confident and ready to give yourself injections in the future.

How and where to inject Kesimpta

Kesimpta should be injected under the skin (subcutaneously) in your abdomen or thigh. It can also be injected in your upper arm, but only if someone else is giving you your dose, such as a caregiver or HCP. Make sure to avoid moles, scars, and stretch marks along with patches of skin that are bruised, scaly, or red.

When you’re ready for your dose, wash your hands and remove Kesimpta from the fridge. Leave Kesimpta at room temperature for at least 15 minutes, as room temperature injections hurt less. Inspect your Kesimpta injection after about 15 minutes have passed. It’s OK if you see a small air bubble in your Kesimpta device, but don’t use it if you see visible particles or cloudiness. Your pharmacy team can help you get a replacement product if so.

Here are a few device-specific pointers.

Pre-filled syringe

1. Clean your injection site with an alcohol wipe.

2. Remove the needle cap from the pre-filled syringe.

3. Pinch your skin with one hand while inserting the needle at a 45-degree angle into your skin with your other hand.

4. Slowly press down on the plunger until you have fully injected Kesimpta.

5. Continue to hold the plunger down for an additional 5 seconds. Then, slowly release the plunger until the needle is covered.

6. Cover blood or blood droplets at your injection site with a cotton ball. You can apply a bandage, if needed. Don’t rub the injection site.

7. Throw away the entire pre-filled syringe into a sharps container. Each syringe only contains one dose.

Sensoready Pen

1. Clean your injection site with an alcohol wipe.

2. Remove the cap from the Sensoready Pen and throw it away.

3. Hold the pen at a 90-degree angle to your injection site. Press the Sensoready Pen against your skin.

4. You’ll hear two clicks. The first click will alert you that the injection has started. You’ll see a green progress indicator in the viewing window of the pen that will indicate the progress of your injection.

5. A second click will alert you that the injection is almost complete. Your injection is complete once the green progress indicator stops moving.

6. Cover blood or blood droplets at your injection site with a cotton ball. You can apply a bandage, if needed. Don’t rub your injection site.

7. Throw away the entire Sensoready Pen into a sharps container. Each pen only contains one dose.

3. Kesimpta has specific storage recommendations

Like many other injectable medications, Kesimpta should be chilled when it's not in use. Store it in the fridge, between 36°F to 46°F, in its original container. Don’t remove it from the carton until you’re ready to use it. Don’t put it in the freezer or shake it, either.

There is some flexibility though. You can remove Kesimpta from the fridge and leave it at room temperature for up to 7 days. This is especially helpful if you’re traveling. However, you’ll want to keep it under a temperature of 86°F, and make sure to administer your dose within the 7-day timeframe. Throw away any unused Kesimpta after 7 days (or if it was exposed to freezing or hot temperatures at any point).

4. There aren’t too many drug interactions

Compared to many other medications, Kesimpta doesn’t have many confirmed interactions with medications or foods. But it may interact with other medications that suppress or calm your immune system, such as corticosteroids. This interaction can increase your risk of infection. Prednisone is one common corticosteroid.

Give your HCP and pharmacist a complete list of all medications, supplements, and vitamins you’re taking. This is especially true if you’re taking other medications that affect your immune system. Your HCP may delay your Kesimpta start date until the immune effects of your other medication(s) wear off.

5. Kesimpta is generally safe, but there are some side effects to consider

Kesimpta has a few side effects you should keep in mind. The most common Kesimpta side effects include:

• Upper respiratory tract infections, such as the common cold

• Injection site reactions, such as pain, itching, or swelling where you injected your dose 

• Injection-related reactions

• Headache

• Urinary tract infections

• Back pain

Injection-related reactions refer to general symptoms in the body such as fever, muscle pain, and fatigue. They’re not too common though. What’s more, these body-wide side effects usually decrease with people’s second and third Kesimpta doses. Your HCP may recommend taking a medication such as Tylenol (acetaminophen) or Benadryl (diphenhydramine) alongside your initial injections to help address some of these side effects.

More serious side effects, such as infection, may also occur with Kesimpta. Let your HCP know if you’re currently experiencing signs or symptoms of an infection. They may pause your Kesimpta prescription until you’re feeling better. Serious infections have been reported in some cases.

How to save on Kesimpta

There are ways to save on Kesimpta, which is only available as a reference (“brand-name”) medication. GoodRx can help you navigate between copay savings cards and patient assistance programs to save money on your prescription.

• Save with a copay savings card. If you have commercial insurance, you may be eligible to pay as little as $0 for Kesimpta using a savings card from the manufacturer.

• Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Kesimpta’s patient assistance program, which offers the medication free of charge.

Why trust our experts?

Written by:

Mandeep Sohal, PharmD

Mandeep Sohal, PharmD, has more than 7 years of experience in the pharmaceutical industry and is licensed in California. In his career, he’s had experience with specialty pharmacy, community pharmacy, pharmacy benefit management, and pharmaceutical manufacturers.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Amy B. Gragnolati, PharmD, BCPS

Amy Gragnolati, PharmD, BCPS, is a pharmacy editor for GoodRx. Amy currently holds her pharmacist license in Georgia and California.

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