What Are TNF Inhibitors?
Tumor necrosis factor (TNF) inhibitors are a type of anti-inflammatory drug. They treat psoriasis by blocking TNF-alpha. It's a protein in your body that produces inflammation and leads to the excess growth of skin cells.
TNF inhibitors are biologic drugs. They target certain immune system proteins. These medicines belong to a group of medications called disease modifying anti-rheumatic drugs (DMARDs).
How Do TNF Inhibitors Work?
TNF inhibitors block the cytokine TNF-alpha.
In psoriasis, you have too much TNF-alpha in your skin. This causes your body to make too many skin cells. The extra skin cells pile up and form scaly plaques. Blocking TNF-alpha stops inflammation and slows your body's production of new skin cells.
Which TNF Inhibitors Are Used to Treat Psoriasis?
The FDA has approved several TNF inhibitors approved to treat moderate-to-severe plaque psoriasis:
When Are TNF Inhibitors Prescribed for Psoriasis?
Each type of TNF inhibitor for the treatment of psoriasis is approved for specific groups of people and types of the condition:
How Do You Take TNF Inhibitors?
Cimzia, Enbrel, and Humira come as injections. The most common way to take these medicines is to give them to yourself. Using a small needle, you inject the medicine into the skin of your belly or thighs.
You get Remicade at your doctor's office as an infusion. A health care provider places a needle that's attached to a thin tube into a vein. A TNF inhibitor infusion takes about 2 hours.
The dose is different for each TNF inhibitor:
Cimzia. Two injections of 200 milligrams each (400 milligrams total) every other week. People who weigh 198 pounds or less may get a first dose of 400 milligrams (two 200-milligram injections) at weeks 0, 2, and 4, followed by 200 milligrams every other week.
Enbrel. In adults, 50 milligrams by injection twice a week for 3 months, then 50 milligrams once a week. Some people must keep taking Enbrel twice a week long term to control their psoriasis. In children: 0.8 milligrams per kilogram of body weight a week, with a maximum of 50 milligrams a week.
Humira. The first dose is 80 milligrams, then 40 milligrams by injection every other week starting a week after the first dose. Some people need to take a 40-milligram dose every week to control their disease.
Remicade. The dose is 5 milligrams per kilogram of weight by infusion at 0 weeks, 2 weeks, and 6 weeks. Then you take it once every 8 weeks. Some people will need a higher dose or more frequent doses to control their psoriasis.
Sometimes doctors prescribe a TNF inhibitor with treatments like these to help it work better:
- Topical corticosteroids
- Topical vitamin D analogues like calcipotriene or calcitriol
- Other DMARDs like acitretin (Soriatane), apremilast (Otezla), cyclosporine, or methotrexate,
- Phototherapy, which exposes the skin to ultraviolet light to clear up plaques
The goal of treatment with TNF inhibitors is to put you into remission, which means you have clear skin and no psoriasis symptoms.
How Effective Are TNF Inhibitors?
Dermatologists use a tool called the Psoriasis Area Severity Index (PASI) to determine how severe psoriasis is and how much of the body it covers. A PASI score of 75% means the drug improved psoriasis symptoms by 75% from when you started treatment. PASI 75 is a big improvement. Because psoriasis drugs have gotten better, today scores can get even higher; for example, PASI 90.
Here are clinical study results for Cimzia, Enbrel, Humira, and Remicade:
Are TNF Inhibitors Safe?
While these medicines can be safe for many people, they do have risks. All of the TNF inhibitors have a boxed warning, which is the most serious safety warning a drug can carry. The warning is because these medications may increase the risk for certain cancers and severe infections.
TNF inhibitors are linked to an increased risk for several types of cancer, including lymphoma, leukemia, and skin cancer. These medicines may also increase the risk for serious bacterial, viral, or fungal infections, including:
- Bacterial sepsis, a life-threatening, body-wide infection
- Fungal infections like histoplasmosis
- Tuberculosis (TB), a lung infection
People who are 65 or older and those who take immune-suppressing medicines like corticosteroids are more likely to get serious infections.
Although serious side effects are rare, your doctor will watch over you for them during your treatment. Your doctor should test you for TB and hepatitis B before you start taking a TNF inhibitor. If you test positive, you'll get medicine to clear up the infection.
Your doctor will monitor you for TB and other infections while you're taking a TNF inhibitor. If you develop TB or any other serious infection, you'll need to stop taking the TNF inhibitor and take medicine to clear up the infection.
Before you start on a TNF inhibitor, make sure you're up-to-date on all your recommended vaccines, including:
- Flu
- Human papillomavirus (HPV)
- Pneumococcal (pneumonia, meningitis)
- Shingles
- Tetanus
Avoid live vaccines like measles, mumps, rubella (MMR) and chickenpox while taking a TNF inhibitor because they could make you sick.
Other serious side effects that have been reported with TNF inhibitors include:
- A severe allergic reaction called anaphylaxis
- Hepatitis B virus reactivation in people who already had this virus in their body
- New or worsening multiple sclerosis
- Low levels of red blood cells, white blood cells, or platelets
- New or worsening heart failure
- Heart attack (with Remicade)
- Liver failure (with Remicade)
- Drug-induced lupus
Your doctor may tell you to stop the TNF inhibitor if you develop any of these side effects.
TNF inhibitors are safe to take during pregnancy and while nursing. There's no evidence that these medicines harm a mother or growing baby.
You shouldn't take these medicines if you have:
- An allergy to the TNF inhibitor or to any of its ingredients
- A hepatitis B, TB, or sepsis infection
- Cancer of the bone marrow, spleen, or thymus
- Moderate to severe heart failure (avoid Remicade)
You may be at higher risk for side effects from a TNF inhibitor if you:
- Take another immune-suppressing drug, such as a corticosteroid, methotrexate, or another biologic drug with it
- Have a condition like diabetes that increases your risk for infections
- Are over age 65
- Lived in or traveled to areas where TB or fungal infections like histoplasmosis spread, or you have been exposed to these infections
- Have multiple sclerosis, heart failure, or a blood disorder
- Have granulomatosis with polyangiitis, a rare disorder that inflames the blood vessels
What Are the Common Side Effects of TNF Inhibitors?
Most side effects from TNF inhibitors are mild. These are the side effects people in clinical trials of TNF inhibitors reported most often, and how to manage them:
Injection site reactions. Up to 40% of people who get TNF inhibitors have symptoms like swelling, pain, or itching in the area where they got the injection. These symptoms can last for 2 to 5 days. They should stop after you've been on treatment for a few months. To treat injection site reactions, you can hold ice to the area and take an antihistamine.
Infusion reactions. Nausea, fever, redness, or itching are possible reactions to the TNF infusion. Usually these side effects start within 10 minutes after you get the infusion, but it could take up to 24 hours for them to show up. Some people have a delayed reaction, with symptoms like joint pain, fever, and tiredness that start 1 to 14 days after the infusion. Call your doctor if you think you're having an infusion reaction. Pain relievers like acetaminophen (Tylenol) and antihistamines may help.
Severe infusion reactions are rare. Symptoms include chest tightness, trouble breathing, swelling in the throat, hives, or a rash. If you have these symptoms, your health care provider will stop the infusion right away.
Infections. Because these medicines suppress part of your immune system, you're more likely to catch infections like colds, sinus infections, and the flu. You may be able to manage the symptoms with over-the-counter medicines. If bacteria caused the infection, your doctor might prescribe antibiotics to treat it. Urinary tract infections are also common, and are treatable with antibiotics.
Headache. If you develop a headache after taking a TNF inhibitor, get plenty of rest. Drink a lot of water. Take an over-the-counter pain reliever. Call your doctor if the headaches last for more than a week or get worse.
Nausea, diarrhea, and belly pain. Eating smaller, more frequent meals can help to relieve nausea. Choose bland foods like crackers and rice. Take small sips of water. For belly pain, hold a heating pad to your abdomen.
Muscle or bone pain. Some people have pain in their back or other joints. An over-the-counter pain reliever may relieve it.
How Much Do TNF Inhibitors Cost?
The cost varies for each of these drugs, and it differs based on the dose you take. In general, prices range from several hundred to several thousand dollars per dose. How much you actually pay depends on your insurance coverage, copay, and other factors.
If you have private insurance, you may be able to get a savings card from the manufacturer. With this card you'll pay as little as $0 a dose for Cimzia, Enbrel, Remicade, or Humira. If you don't have insurance, you may qualify for a patient assistance program from the manufacturer that provides these medicines free of charge.
Biosimilars might also save you money. These medicines work in the same way as the name-brand TNF inhibitors and they have the same safety profile, yet they may be less expensive.
Humira has several biosimilars on the market, including:
- Adalimumab-aacf (Idacio)
- Adalimumab-aaty (Yuflyma)
- Adalimumab-adbm (Cyltezo)
- Adalimumab-adaz (Hyrimoz)
- Adalimumab-afzb (Abrilada)
- Adalimumab-aqvh (Yusimry)
- Adalimumab-atto (Amjevita)
- Adalimumab-bwwd (Hadlima)
- Adalimumab-fkjp (Hulio)
Remicade biosimilars include:
- Infliximab-dyyb (Inflectra)
- Infliximab-abda (Renflexis)
- Infliximab-axxq (Avsola)
Etanercept-ezzs (Erelzi) is the biosimilar version of Enbrel.
Clinical Trials of TNF Inhibitors for Psoriasis
Taking part in a clinical trial is another way to save money on treatment and possibly get access to a new medication that isn't available to everyone else yet. Several studies are looking at the safety and effectiveness of already approved TNF inhibitors and new drugs in this class. Some clinical trials compare TNF inhibitors with each other. Other studies compare TNF inhibitors with drugs in other classes to see which one works better.
Visit Clinicalrials.gov to search for studies in your area or in other parts of the country. When you click on a study, you can see:
- Information about the trial and what it's studying
- Whether the study is still enrolling
- Where it's located
- What criteria you need to meet in order to qualify
Another way to find clinical trials is by signing up for the National Psoriasis Foundation's MyStudies. They'll let you know about new research studies in your area. Your psoriasis doctor is also a source of information on clinical trials. They may know about studies happening near you and whether you're a good fit for them.
Learn more about clinical trials.
Is a TNF Inhibitor Right for Me?
Deciding on a treatment for your plaque psoriasis is a big decision. This recap of the important facts about IL inhibitors will give you the information you need to talk to your doctor and make the right decision for you.
Prior Treatments: If you take immune-suppressing medicines like corticosteroids, you're more likely to get serious infections while taking TNF inhibitors. Talk to your doctor about all medications and supplements you take as you plan your psoriasis treatment.
How You'll Take Your Medication: Most TNF inhibitors come as injections that you take yourself. If you're not comfortable doing this, you can take one type, Remicade, at your doctor's office as an infusion. You'll need to decide if this is convenient for you in the long run.
Potential Side Effects: Most of the possible side effects of TNF inhibitors are mild. They include reactions at the injection or infusion site, such as swelling and soreness. These usually go away after a few days, but in some cases they may linger or you could have a delayed reaction. Because these medicines tamp down part of your immune system, you're more likely to catch infections like colds, sinus infections, and the flu that you may be able to manage the symptoms with over-the-counter medicines.
Costs: Affordability is an important part of deciding on your plaque psoriasis treatment. TNF inhibitors are not inexpensive, but your actual out-of-pocket expense depends on many things. With private insurance, you may be able to get a manufacturer's savings card that lets you pay as little as $0 a dose for some TNF inhibitors. If you don't have insurance, you may qualify for a patient assistance program that provides these medicines free of charge. You can also get help with copay costs from a nonprofit organizations.
Also, you can save money by using a biosimilar medicine. They work in the same way as the name-brand TNF inhibitors and have the same safety profile, but may be less expensive.
Medical History and Related Conditions: Your doctor will need to know your complete medical history before they prescribe a TNF inhibitor for you.
Certain conditions that raise your risk for infections may make it more likely that you'll have serious side effects with TNF inhibitors. This includes diabetes and certain blood disorders, among other.
If you have an allergy to the TNF inhibitor or to any of its ingredients, a hepatitis B, TB, or sepsis infection, or certain cancers, you should not take a TNF inhibitor. If you have moderate to severe heart failure, you should not take Remicade.