Spesolimab belongs to the class of medications called monoclonal antibodies, specifically, it is an interleukin-36 inhibitor. It is used to treat flare-ups of generalized pustular psoriasis (GPP) in adults and children 12 years of age and older who weigh at least 40 kg. GPP is a sudden occurrence of skin blisters (pustules) that develop over large areas of the body. People with GPP have an overproduction of interleukin-36R (IL-36R), a protein that is part of the immune system when the body's defenses are activated.

Spesolimab works by blocking the action of interleukin-36 (IL-36), reducing the pustules, pain, and inflammation of the skin.

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.

To treat a flare-up of GPP, spesolimab is given as a single dose of 900 mg.

It is injected intravenously (into a vein) by a health care professional, usually in a clinical setting such as a hospital clinic, over 90 to 180 minutes. This process is called an intravenous infusion.

If the symptoms of the flare-up do not go away within a week, your doctor may suggest that you receive an additional dose of the medication.

Spesolimab may also be used to prevent GPP flare-ups.  To prevent GPP flare-ups, 300 mg (2 × 150 mg) may be given subcutaneously (under the skin) every 4 weeks, starting 4 weeks after the last intravenous dose.

If preventive treatment is given without having treated a flare-up, the first dose of spesolimab is 600 mg (4 × 150 mg) injected subcutaneously.

Spesolimab is used with the guidance and supervision of a doctor. Your doctor or nurse will help you with preparing and injecting your first dose (or first few doses). Do not attempt to prepare or inject this medication on your own until you completely understand how to inject a dose. If you are having difficulty giving yourself injections, talk to your health care provider.

Rotate the injection sites (arms, thighs, upper buttocks, or stomach) to minimize injection site skin irritation. Injections given on the same day should be given at sites at least 2 cm apart.

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.

If you miss a dose, take it as soon as possible 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.

This medication should be stored in the refrigerator and infused immediately after it has been prepared. Protect it from light and keep it out of the reach of children. Do not allow it to freeze. 

60 mg/mL
Each 1 mL of clear, sterile solution contains 60 mg of spesolimab. Nonmedicinal ingredients: arginine hydrochloride, glacial acetic acid, polysorbate 20, sodium acetate trihydrate, sucrose, and water for injection. 

150 mg/mL
Each 1 mL of clear, sterile solution for subcutaneous injection contains 150 mg of spesolimab. Nonmedicinal ingredients: arginine hydrochloride, glacial acetic acid, polysorbate 20, sodium acetate trihydrate, sucrose, and water for injection. 

Do not take this medication if you are allergic to spesolimab 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.

• fatigue
• itchiness
• redness, swelling, hardening, warmth or pain at the injection site

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:

• signs of infection (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• symptoms of an upper respiratory tract infection (e.g., fever, sinus pain, headache, fatigue, runny nose, or nasal congestion)
• symptoms of a urinary tract infection (e.g., pain when urinating, urinating more often than usual, low back or flank pain)

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

• signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
• signs of a severe allergic reaction that may occur days to weeks after receiving an infusion (e.g., skin rash [different from GPP], fever, swollen lymph nodes, facial swelling or mouth sores)

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.

Hypersensitivity reaction: As with other monoclonal antibodies, spesolimab may cause your body to produce antibodies to "defend" your body from the medication. When this happens, an allergic reaction develops. Often, allergic reactions are experienced as a rash, hives or itching. On rare occasions, a severe allergic reaction may occur, causing difficulty breathing, abdominal cramps, nausea and vomiting, or swelling of the throat (anaphylaxis).

In rare cases, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS syndrome) may occur. This reaction involves symptoms including fever, swollen glands, yellowing of the skin or eyes, flu-like symptoms with skin rash or blistering or other organ involvement. These reactions are medical emergencies. Get immediate medical attention if you have symptoms of a severe allergic reaction. If you experience any unusual symptoms, contact your doctor.

Infection: Spesolimab may temporarily decrease the effectiveness of your body's defenses against infection. This makes the body more likely to develop infections due to bacteria, viruses, and fungi. If you have a history of chronic or frequent infections, 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.

People with a history of tuberculosis may need to take medication to prevent tuberculosis from flaring up.

If you notice symptoms of a serious infection, such as fever, chills, headache, flu-like symptoms, feeling tired, cough, blood in the sputum, shortness of breath, night sweats, weight loss, nausea, vomiting, diarrhea, frequency of urination or burning while passing urine, redness or swelling of skin or joint, cold sores, tooth pain, or new or worsening pain in any part of the body, contact your doctor as soon as possible.

Vaccines: Live vaccines such as yellow fever, BCG, cholera, typhoid, varicella, meningococcal, and diphtheria should not be given at the same time as receiving spesolimab. They work by administering a small amount of live bacterium into the body to cause the body to develop defenses against them. When they are given at the same time as a medication that may reduce the strength of your immune system, it may cause a severe infection.

Live vaccines should be given at least 4 weeks before treatment with spesolimab or 16 weeks after treatment with spesolimab.

The effectiveness of giving other vaccines while using this medication has not been studied.

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.

Breast-feeding: is not known if spesolimab 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 younger than 12 years of age or weighing less than 40 kg.

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.