What Are IL Inhibitors?
IL inhibitors, short for interleukin inhibitors, are a group of drugs used to treat autoimmune conditions, including moderate to severe plaque psoriasis.
IL inhibitors bind to a specific part of your immune system called interleukins. If you live with psoriasis, these proteins often trigger inflammation in your body when your immune system overreacts and makes too many of them. IL inhibitors stop this from happening, which can reduce your psoriasis symptoms.
What IL Inhibitors Are Used to Treat Psoriasis?
The FDA has approved several different IL inhibitors for the treatment of plaque psoriasis, depending on the specific protein they target. The options include:
How Do IL Inhibitors Work?
Interleukins tell your body when it’s time to ramp up inflammation. Usually, this helps you stay healthy. When your immune system detects a harmful invader, like a bacterial infection, an inflammatory response can fight it off. But if you live with psoriasis, the proteins involved in your immune system, including interleukins, overreact. They keep triggering an inflammatory response even when there aren’t invaders to fight. This can cause your skin to become inflamed and make skin cells too quickly, which results in itchy, scaly plaques. IL inhibitors “tell” interleukins to stay quiet so your immune system stays at rest.
Different IL inhibitor medicines target different interleukins. Each type plays a slightly different role in your body’s inflammation process, but all have been shown to help treat moderate to severe plaque psoriasis.
When Are IL Inhibitors Prescribed for Psoriasis?
Your psoriasis severity is based on how much of your body is affected.
Mild psoriasis: Less than 3% of your body is affected. This type is usually mild and doesn't interfere too much with your daily activities. IL inhibitors usually aren’t needed to treat mild psoriasis. A prescription cream that you rub onto your skin is usually enough to improve your symptoms.
Moderate psoriasis: Affects 3% to 10% of your body. You’ll also have larger and more widespread plaques that may itch or be uncomfortable enough to interfere with your sleep, work, or relationships. Your treatment could include IL inhibitors.
Severe psoriasis: More than 10% of your skin is inflamed. You’ll have large areas of skin plaques that can be very itchy, painful, and may crack and bleed. This can have a severe effect on your daily life and cause a lot of stress. You’ll usually need an IL inhibitor or another type of systemic medication to treat it. Systemic medications work throughout your body, not just on your skin.
As your doctor thinks about your treatment options, they’ll take into account where your psoriasis symptoms are. Inflamed skin in certain areas, like your face, scalp, palms, soles, or genitals, may bother you more. Systemic medications are often needed to clear them up.
The IL inhibitors listed above are all FDA-approved for the treatment of moderate to severe psoriasis.
IL inhibitors are usually “second-line therapies” for moderate to severe psoriasis. That means that your doctor usually won’t prescribe them, and your health insurance may not cover them, until you try other treatments.
IL inhibitors aren’t a good fit for everyone. For instance, your doctor may not prescribe them if you have an active infection, an infection that goes away and comes back, or some types of cancers. Until more studies are done, IL inhibitors are not believed to be safe to take while you’re pregnant or breastfeeding.
How Do You Take IL Inhibitors?
A big appeal of IL inhibitors is that they’re convenient. They usually come in pre-filled syringes (shots) or auto-injector pens that you can inject yourself at home. They go just under the skin of your thigh, lower belly, or upper arm.
If your doctor wants you to try IL inhibitor shots, you’ll likely have your first dose at their office so they can make sure you don’t have an allergic response. They’ll also train you on the right way to give yourself the shot at home. You’ll learn how to:
- Handle and store the medication
- Prepare the place on your skin where the needle goes in
- Inject the medication to ensure it’s given correctly and comfortably
- Safely dispose of used needles and syringes
The dose you’ll get will depend on the IL inhibitor you take. There’s usually a “loading dose” at first to trigger your body’s response to the medicine. Then, you may get “maintenance doses” after that.
The dosing schedule below is what experts generally advise for adults. But your doctor may adjust it based on your needs and how you respond to the drug. Always follow their instructions and call their office when you have questions.
For tildrakizumab, the loading dose is 100 mg at weeks 0 and 4 and 100 mg every 12 weeks thereafter. If you take ustekinumab (Stelara), the loading dose is 45 mg (90 mg if you weigh more than 100 kg) at weeks, repeated every 12 weeks thereafter.
IL inhibitors are usually long-term treatments. Your symptoms may come back if you stop taking them. But there are lots of reasons why you may need to stop. For instance, you may want to try to get pregnant or need surgery for a different health issue. You might also choose to stop one of these medications if you don’t like the side effects it causes. Check in with your doctor regularly so they can adjust your dose or switch you to a different medication if needed.
How Effective Are IL Inhibitors?
The FDA has approved these drugs based on studies that show they are safe and work well for relieving plaque psoriasis symptoms. The effectiveness of medications for treating plaque psoriasis are typically measured by the Psoriasis Area Severity Index (PASI) score.
The PASI is a formula that doctors use to figure out how severe your psoriasis is and how much of your body it affects at a given time. It’s also used in research to measure how well a treatment improves psoriasis symptoms. For instance, a PASI score of 75 means that a treatment improved psoriasis symptoms by 75%.
Psoriasis treatments have improved so much in recent years that some clinical trial results include people who’ve reached a PASI score of 90 or even 100. That means that their symptoms improved 90% or 100%.
Here’s a look at some results IL inhibitors have been able to achieve.
Are IL Inhibitors Safe?
These kinds of drugs often work well and cause only mild side effects. But like all medications, IL inhibitors come with risks that you need to know about.
Some common side effects of IL inhibitors include:
- Pain, redness, or swelling where the needle went in
- Upper respiratory infection
- Headache
- Fatigue (feeling really tired)
Although less common, you could also have:
- Fungal, bacterial, or viral infection
- Tuberculosis (TB), especially if you’ve already had it before
- Severe allergic reaction
- Neurological disorders, including multiple sclerosis and seizures
- Inflammatory bowel disease (IBD)
The FDA has placed a black box warning – the most serious warning possible – on brodalumab (Siliq) for its risk of suicidal thoughts and behavior. If you’re prescribed this medication, you’ll need to enroll in a Risk Evaluation and Mitigation Strategy (REMS) program.
It’s important for your doctor to check your health before you start treatment, including screening you for some health conditions like tuberculosis. They’ll regularly check for side effects or symptoms of other issues, like infections, while you’re taking the medication.
Talk with your doctor about what you can expect, and any concerns you might have about taking an IL inhibitor.
How Much Do IL Inhibitors Cost?
IL inhibitors can be expensive, whether or not you have health insurance.
If you’re not covered by a health plan, you may pay several thousand dollars per month. If you are insured, your actual out-of-pocket cost will depend on things like your deductible, copays, and your plan's pharmacy coverage. You’ll need to call the number on the back of your insurance card to find out the exact amount you’ll pay.
A few resources may be able to help lower your out-of-pocket costs for treatment with an IL inhibitor. They include:
Manufacturer assistance programs
Many drug companies that make IL inhibitors offer patient assistance programs (PAPs) to help reduce out-of-pocket costs. They may give you the medication at a reduced cost or, sometimes, for free.
You may also be able to get a copay card that can reduce how much you’ll pay out of pocket. Some drug companies will also help answer questions you have about your insurance coverage or other ways to get financial help.
Assistance programs include:
- Bimekizumab (Bimzelx): Bimzelx Navigate Savings Program
- Brodalumab (Siliq): SILIQ Solutions Program
- Guselkumab (Tremfya): Tremfya with Me
- Ixekizumab (Taltz): Taltz Together
- Risankizumab (Skyrizi): Skyrizi Complete
- Secukinumab (Cosentyx): Cosentyx Connect
- Tildrakizumab (Ilumya): Ilumya Support
- Ustekinumab (Stelara): Janssen CarePath
Clinical Trials of IL Inhibitors for Plaque Psoriasis
Clinical trials are the main way doctors come up with better treatments for psoriasis, including new IL inhibitors. They depend on people volunteering to take part.
A clinical trial may be an option for you if:
- Other treatments haven’t worked well.
- You’re interested in learning more about new therapies.
- You’d like to be part of research that could help others who live with psoriasis.
Joining a clinical trial may cover some of your treatment costs. You may also get to see doctors more often and at no extra cost to you.
If you’re interested in joining a clinical trial:
- Talk to your doctor. They can steer you toward some trials that might be a good fit.
- Search a clinical trial database. Websites like ClinicalTrials.gov list all ongoing clinical trials. You can search by condition, location, treatment stage, and more.
- Join a psoriasis patient registry. These groups collect information about people with psoriasis and help match volunteers with clinical trials. Some are sponsored by government agencies. Others are run by hospitals, nonprofits, or private companies. Join one that’s run by a sponsor you trust.
Learn more about clinical trials.
Is an IL Inhibitor Right for Me?
Choosing a treatment for your moderate to severe psoriasis is a big decision. You and your doctor will make it together, based on the following:
Prior treatments: If other treatments, like topical creams and light therapy, haven’t worked well to manage your psoriasis, an IL inhibitor may be the next step.
How you’ll take your medication: You typically take IL inhibitors by shots you give yourself. Many people find this easier than an IV medication that you have to get at an infusion center. Your preference for how you’ll take your medication, and how often, can factor into the type of treatment you choose.
Potential side effects: While IL inhibitors are generally safe, they can increase your risk of infections and other side effects. You’ll want to make sure you fully understand the risks vs. the benefits before you decide. You’ll also need to visit your doctor regularly so they can keep an eye on your progress.
Costs: Your finances can play a big role in your treatment decision. You’ll want to make sure you understand exactly how much an IL inhibitor will cost you out of pocket. Review your health insurance policy and make sure you understand your out-of-pocket costs, including copays and deductibles. Look into any patient assistance program offered by the company that makes the medication.
Medical history and related conditions: IL inhibitors aren’t right for everyone, including people with a history of infections, certain ongoing conditions, or anyone who’s planning to be pregnant or breastfeeding. If you have psoriatic arthritis, an IL inhibitor may be a good choice for you because it can help treat both joint and skin symptoms. Talk through all your options with your doctor.