Biologics and Biosimilars for Ulcerative Colitis

Medically Reviewed by Melinda Ratini, MS, DO on June 12, 2022
5 min read

Your diarrhea is back. You’ve spotted blood in your poop. And you’re tired all the time. It could be an ulcerative colitis (UC) flare.

Ask your doctor about biologic or biosimilar therapies for ulcerative colitis if your current treatment isn’t working. These medications might help you feel better now and keep future flares to a minimum. A doctor can help you figure out if they’re right for you.

Here are some questions to get you started.

Biologics are drugs that change how your immune system works. They’re made from living cells. They can ease inflammation by blocking proteins that play a role in UC.

Your doctor might suggest a biologic when standard treatments fail. That means you take medication but UC symptoms still cause a lot of problems, including:

  • More than five bowel movements a day
  • Blood in your poop or on the toilet paper
  • Interfering with work or school
  • Trouble doing everyday things

There are five biologics approved to treat moderate to severe UC. They fall into different groups based on which protein they target. They include:

Anti-tumor necrosis factor (anti-TNF) inhibitors: Your doctor will likely start you off on an anti-TNF biologic. Scientists know a lot about these drugs. There’s also some evidence they may work better than other types of biologics in people who’ve never tried a biologic before.

Examples include:

Integrin receptor antagonists. This type of biologic only targets cells in the lining of your gut. There’s evidence they may be safer than other biologics. Keep in mind all biologics are considered safe. But integrin receptor antagonists seem to be less likely to raise your odds of infections. We need more research to know for sure. Vedolizumab (Entyvio) is approved for UC.

Interleukin-12 and interleukin-23 antagonists: These biologics target proteins called interleukin-12 and interleukin-23. Both are linked with higher levels of inflammation in the gut. Research suggests ustekinumab (Stelara) works well for UC.

These drugs are “highly similar” to approved biologics. Unlike chemical medications, scientists can’t make an exact copy of a drug made from living cells.

Examples of biosimilars used to treat UC include:

  • Adalimumab-adbm (Cyltezo)
  • Adalimumab-atto (Amjevita)
  • Infliximab-abda (Renflexis)
  • Infliximab-dyyb (Inflectra)
  • Infliximab-qbtx (Ixifi)

Your doctor may not suggest a biosimilar right off the bat. But your health insurer might want you to try a biosimilar over a biologic to save money.

Some biosimilars are interchangeable with biologics. That means your pharmacist can switch you to a biosimilar unless your doctor says otherwise.

Biosimilars are approved only when scientists can show they work just as well as biologics. But if you’re worried about how well they work, ask your doctor if biosimilars are OK for you.

Everyone’s immune system is different. You may have fewer symptoms within 2 to 4 weeks. But it might take up to 8 weeks to see a big improvement.

You might respond to biologic drugs faster if you:

  • Have lower levels of inflammation
  • Are younger
  • Have never had IBD surgery
  • Are on another drug to suppress your immune system

The type of biologic you take may also play a role. Some studies suggest anti-TNF inhibitors work the quickest. Integrin receptor antagonists may work a little slower. More research will provide the answers.

Your doctor will probably ask about your symptoms. For instance, it’s a good sign if your bleeding and diarrhea stop. The biologic should also boost your general well-being and quality of life.

But your doctor may also run some tests. They might:

  • Test your blood
  • Take a stool sample
  • Give you a colonoscopy

It’s safe to take these drugs on a long-term basis. And you may not have any issues with your treatment. But here are some things to consider:

Higher odds of infection. Biologics don’t make you sick. But these drugs can make it harder for your immune system to fight off germs. There’s a chance they might reactivate viruses that are already in your blood.

Before you start biologic treatment, your doctor will check your blood for infections like:

  • Tuberculosis (TB)
  • Hepatitis B
  • HIV

After you start a biologic, tell your doctor anytime you have signs of an infection. Watch for symptoms such as:

  • Diarrhea or bloody poop
  • Fever and chills
  • Cough
  • Sore throat

You can take steps to stay healthy. Wash your hands, wear a mask, and avoid close contact with sick people. And stay up to date on your vaccines. Your doctor will let you know which ones are right for you.

Side effects and other reactions. Biologics go into your body one of two ways: a shot or through a vein in your arm. You may get pain, redness, swelling, or bruising where the medicine goes into your skin.

It’s possible to have an allergic reaction to a biologic. After a shot or infusion, get medical help right away if you notice:

  • Shortness of breath
  • Chills
  • Redness
  • Itchy skin, eyes, or lips
  • Full body rash

Tell your doctor about any new symptoms that show up when you start your biologic.

It’s less common, but some biologics might affect your nervous system or cause a lupus-like reaction. That could trigger symptoms such as:

  • Numbness or tingling
  • Vision changes
  • Sudden swelling in your ankles or hands
  • Skin rashes that get worse in the sun
  • Joint pain or muscle aches
  • Fever

Your doctor might want you to pair a biologic or biosimilar with another UC treatment. That could include a medication called an immunomodulator. These drugs ease inflammation by changing how your immune system works.

Combination therapy might help your UC treatment work better. But you also boost your chances of side effects and drug-related health issues when you mix medication. Your doctor will help you decide what’s best.

Don’t take biologics with tofacitinib (Xeljanz). That’s a pill used to treat UC. It’s in a class of drugs called JAK inhibitors. If you’re no longer taking biologics, your doctor might want you to take tofacitinib along with short-term corticosteroids if your symptoms are really serious.

You might need to try more than one biologic on your road to remission. Your doctor will tell you how to switch drugs safely. Biologics may not work very well when you start and stop treatment the wrong way.

Biologics can ease your symptoms for months or years. But over time, they may not work as well as they did at first. There’s no way to predict when or if this will happen. But you can tell your doctor anytime you have symptoms such as diarrhea or bleeding. Before they change your treatment, they’ll want to rule out infections or other stomach disorders that look like UC.

They can also run some tests to find out if you’re still responding to your biologic. If your medication stops working, your doctor may:

  • Switch to a different kind of biologic
  • Boost your dose
  • Add another immunosuppressant

Your UC doctor will let you know how often you should come in for checkups. Be sure to keep up routine visits with your primary doctor, too. UC can occur alongside other health issues, so it’s a good idea to have more than one set of eyes on you.

Show Sources


Mayo Clinic: “Ulcerative colitis flare-ups: 5 tips to manage them.”

UpToDate: “Management of moderate to severe ulcerative colitis in adults.”

Crohn’s & Colitis Foundation: “Medication Options for Ulcerative Colitis,” “Fact Sheet: Biologics,” “Biosimilars: What You Should Know.”

Gastroenterology & Hepatology: “Emerging Treatment Options in Mild to Moderate Ulcerative Colitis,” “Residual Inflammation and Ulcerative Colitis in Remission,” “Vaccinating Patients With Inflammatory Bowel Disease,” “What to Do When Biologic Agents Are Not Working in Inflammatory Bowel Disease Patients.”

Clinical Gastroenterology and Hepatology: “First- and Second-Line Pharmacotherapies for Patients with Moderate to Severely Active Ulcerative Colitis: An Updated Network Meta-Analysis,” “Tofacitinib for Biologic-Experienced Hospitalized Patients With Acute Severe Ulcerative Colitis: A Retrospective Case-Control Study.” 

Clinical and Experimental Gastroenterology: “Anti-Integrins for the Treatment of Inflammatory Bowel Disease: Current Evidence and Perspectives.”

Frontiers in Pharmacology: “Novel and Emerging Therapies for Inflammatory Bowel Disease.”

FDA: “FDA Approves Cyltezo, the First Interchangeable Biosimilar to Humira,” “FDA approves new treatment for moderately to severely active ulcerative colitis.”

Best Practices & Research Clinical Gastroenterology: “Biosimilars in ulcerative colitis: When and for who?”

World Journal of Gastroenterology: “Time to clinical response and remission for therapeutics in inflammatory bowel diseases: What should the clinician expect, what should patients be told?” “Risk of infections associated with biological treatment in inflammatory bowel disease.”

The American Journal of Gastroenterology: “ACG Clinical Guideline: Ulcerative Colitis in Adults.”

Expert Opinion on Drug Safety: “Long-term safety of approved biologics for ulcerative colitis.”

Johns Hopkins Arthritis Center: “Side Effects of Biologic Medications.”

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