Wezlana (ustekinumab or ustekinumab-auub) is a biologic medication and the first FDA-approved biosimilar to Stelara (ustekinumab). As a biosimilar, it’s approved to treat the same autoimmune conditions, including plaque psoriasis, psoriatic arthritis, Crohn's disease, and ulcerative colitis. It works by blocking certain proteins called interleukins that cause inflammation in the body. The medication is usually given as an injection under the skin, with doses every 8 to 12 weeks. Common side effects include feeling tired, having a headache, or experiencing common cold symptoms.
Wezlana (ustekinumab) is an interleukin antagonist. It works by blocking two proteins in your immune system — interleukin-12 (IL-12) and interleukin-23 (IL-23) — that play a major role in inflammation. By targeting these proteins, the medication helps to lower inflammation and relieve symptoms from autoimmune conditions.
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Plaque psoriasis
Psoriatic arthritis
Crohn's disease
Ulcerative colitis:
Contact your healthcare provider immediately if you experience any of the following.
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
How to inject Wezlana (ustekinumab) from a prefilled syringe:
Wezlana (ustekinumab) has been available in the United States since January 2025. It was approved by the FDA in October 2023.
No. Wezlana (ustekinumab) isn’t exactly the same as Stelara (ustekinumab), but it’s very close. It’s a biosimilar, meaning it works the same way in the body and is just as safe and effective. Both medications have the same active ingredient, ustekinumab, and are used to treat the same conditions. Even if they look different, they’re made to have the same overall effect. Talk to your prescriber if you have questions comparing both medications.
Yes. Wezlana (ustekinumab) is interchangeable with Stelara (ustekinumab). That means that pharmacies can substitute Wezlana (ustekinumab) for Stelara (ustekinumab) without a new prescription. It can make switching easier and more convenient if you want to switch medications.
Wezlana (ustekinumab) is given as an injection either under the skin or through a vein (intravenous, IV). If you're starting it for Crohn’s disease or ulcerative colitis and haven’t taken this type of medication before, your first dose will be an IV infusion at a clinic. After that, you'll switch to injections under the skin every 8 weeks. For conditions like plaque psoriasis or psoriatic arthritis, you'll get your first two injections under the skin one month apart. Then you'll inject a dose every 12 weeks to help manage your symptoms. Speak to your prescriber about how often you should be injecting this medication.
Weight gain isn’t a common side effect of Wezlana (ustekinumab). If you notice weight gain while taking this medication, talk to your prescriber so they can help figure out what's going on.
Wezlana (ustekinumab) 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.
Wezlana (ustekinumab) can raise your risk of infections, including serious ones that might need hospital care. These can be caused by bacteria, viruses, or fungi. Tell your prescriber about your medical history before starting Wezlana (ustekinumab), especially if you've ever had tuberculosis (TB). Let your care team know right away if you have signs of infection, such as fever, chills, cough, or tiredness — your treatment might need to be paused until you recover.
Wezlana (ustekinumab) weakens your immune system and can raise your risk of certain cancers. Some people developed skin cancer while taking this medication, especially those with a higher risk. Your care team will check your skin regularly during treatment, particularly if you have a history of cancer or other risk factors. Let your prescriber know if you’ve had cancer before or if you notice any new or changing spots on your skin.
Serious allergic reactions, including anaphylaxis and angioedema, have been reported with Wezlana (ustekinumab). If you have a severe reaction, your care team will stop the medication and treat you right away. Get medical help immediately if you have symptoms like trouble breathing, swelling of your face or throat, or a serious rash.
Rare cases of a brain condition called posterior reversible encephalopathy syndrome (PRES) have been reported in people taking Wezlana (ustekinumab). Symptoms can include headache, seizures, confusion, or vision changes. These symptoms can appear anywhere from a few days to months after starting the medication, sometimes even after a year or more. If you have PRES, your care team will stop the medication and provide treatment. Let your prescriber know right away if you notice any of these signs.
Before starting Wezlana (ustekinumab), you or your child should be up to date on all recommended vaccines. While you're being treated, avoid getting live vaccines. You should also avoid the BCG vaccine during treatment, as well as for one year before starting and one year after stopping the medication. Be careful if someone in your household gets a live vaccine since it can spread and pose a risk to you. Non-live vaccines are generally safe, but they might not work as well while you're taking Wezlana (ustekinumab). Check with your care team before getting any vaccines during treatment.
Different types of pneumonia have been reported in people taking Wezlana (ustekinumab), and in some cases, these conditions were serious. Symptoms can include cough and trouble breathing. Let your care team know right away if you have new or worsening breathing problems. You might have to stop taking the medication and receive the appropriate treatment.
Plaque psoriasis
Psoriatic arthritis
Crohn's disease and ulcerative colitis: