Bimekizumab belongs to the class of medications called immunomodulators. It is used to treat moderate-to-severe plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis in adults. When people have any of these conditions, their bodies overproduce certain proteins called interleukins (IL). Increased levels of these proteins cause inflammation which can result in itching, pain, and scaling skin. Bimekizumab blocks the action of 2 types of interleukin-17, (IL-17A and IL-17F), reducing the symptoms of plaque psoriasis.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended dose of bimekizumab is 320 mg injected subcutaneously (under the skin), every 4 weeks for the first 16 weeks. Each 320 mg dose is made up of 2 separate injections of 160 mg. After the first 16 weeks, 320 mg of bimekizumab is given every 8 weeks. A full dose consists of 2 injections (of 160 mg each), given one right after the other. Inject the second syringe at least 3 cm (1 inch) away from the first injection.

When treating psoriatic arthritis or ankylosing spondylitis, the recommended dose is 160 mg injected subcutaneously, every 4 weeks.

This medication is administered by subcutaneous injection in the thigh, upper arm, or abdomen. It is important to change the injection site you're using, rotating between sites, to reduce the risk of fat wasting at the injection site. Avoid injecting into areas that are tender, bruised, or affected by psoriasis.

The solution should be clear-to-slightly milky and colourless-to-pale-brown-yellow. If the solution is discoloured or contains flakes or large particles, do not use the contents of the prefilled syringe. Instead, use a fresh syringe.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

If you are receiving this medication at the doctor's office and you miss an appointment to receive bimekizumab, contact your doctor as soon as possible to reschedule your appointment.

Store this medication in the refrigerator, protect it from light, and keep it out of the reach of children. Do not let this medication freeze. Allow the medication to warm to room temperature for 30 to 45 minutes before you inject it.  If necessary, this medication may be stored at room temperature, protected from light for up to 25 days. Do not return medication that has been stored at room temperature to the refrigerator.

Each mL of clear-to-opalescent, pale-brown-to-light-yellow, preservative-free, sterile solution, contains 160 mg of bimekizumab. Nonmedicinal ingredients: acetic acid, glycine, polysorbate 80, sodium acetate trihydrate, and water for injection.

Bimekizumab is available as 160 mg solution for injection in prefilled syringe and autoinjector.

Do not take this medication if you are allergic to bimekizumab or any ingredients of the medication.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• acne
• cold sores
• cough
• dry, itchy skin
• fatigue
• flu-like symptoms (sudden lack of energy, fever, cough, sore throat, stuffy nose)
• headache
• mouth pain
• pain or redness at the injection site
• small red bumps on the skin
• toothache
• white patches in the throat or mouth

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:

• fungal skin infection
• high blood pressure
• gastroenteritis (e.g., nausea, heartburn, diarrhea, stomach cramps)
• symptoms of infection (e.g., fever or chills, night sweats, muscle aches, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• symptoms of a urinary tract infection (e.g., pain when urinating, urinating more often than usual, low back or flank pain)
• symptoms of a vaginal yeast infection (e.g., curd-like discharge, vaginal itching and burning, painful urination)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., difficulty breathing, hives, swelling of the face or throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Body weight: This medication may not be as effective for people with a body weight over 120 kg. Talk to your doctor if this is a concern.

Infections: This medication can increase the risk of developing an infection, including serious infections such as tuberculosis. Before starting bimekizumab treatment, your doctor may test to see if you have tuberculosis. If you notice signs of an infection such as fever, chills, pain, swelling, or coughing, contact your doctor as soon as possible. This medication should also not be started while you have an active infection.

Tell your doctor if you have a history of infections that keep coming back, or other conditions that might increase your risk of infections such as diabetes. While you are taking bimekizumab, your doctor will monitor you for signs of infection.

Inflammatory bowel disease: If you have inflammatory bowel disease, this medication may make symptoms of your condition worse. Discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you develop symptoms of inflammatory bowel disease, such as fatigue, fever, loss of appetite, abdominal tenderness or swelling, or blood in the stool, contact your doctor as soon as possible.

Vaccines: Before starting this medication, all your immunizations should be up to date. Live vaccines (e.g., BCG, yellow fever) are not recommended for people taking this medication. Talk to your doctor if you need any vaccinations while taking this medication.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately. People who could become pregnant should use effective birth control while taking this medication and for 4 months after the last dose.

Breast-feeding: It is not known if bimekizumab passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.