Anti-TNF Biologics

Anti-TNF biologics are a major group of advanced medicines for moderate to severe Crohn’s disease and ulcerative colitis. They are laboratory-made antibodies that block tumor necrosis factor (TNF), a powerful inflammation signal in the immune system. By calming this signal, anti-TNF drugs can reduce symptoms, heal the gut lining, and lower the risk of hospital stays and surgery for many people with IBD. (academic.oup.com)

Key Takeaways

• Anti-TNF biologics target TNF, a key chemical driver of inflammation in Crohn’s disease and ulcerative colitis. (academic.oup.com)

• Main IBD anti-TNFs include infliximab (IV infusion) and adalimumab, certolizumab, and golimumab (self injections). (academic.oup.com)

• They are used for moderate to severe IBD when simpler medicines are not enough, and often as first “advanced” therapy. (academic.oup.com)

• Serious infection risk goes up on anti-TNFs, so screening for tuberculosis, hepatitis B, and updating vaccines is important. (pfizermedicalinformation.com)

• There is a small increased risk of certain cancers, especially lymphomas and skin cancers, so regular checkups and skin exams are advised. (pfizermedicalinformation.com)

• Most data suggest anti-TNFs can be continued in pregnancy when needed to keep IBD in remission. (pmc.ncbi.nlm.nih.gov)

What are anti-TNF biologics?

Tumor necrosis factor (TNF) is a protein that helps the immune system fight infections. In IBD, the body makes too much TNF, which keeps the gut inflamed and damaged.

Anti-TNF biologics are monoclonal antibodies. They attach to TNF in the blood and tissues, so TNF cannot lock onto its receptors and trigger inflammation. This targeted blocking can rapidly calm gut inflammation and help the bowel lining heal. (academic.oup.com)

Large guidelines for Crohn’s disease and ulcerative colitis recommend anti-TNFs as effective options for inducing and maintaining remission in moderate to severe IBD. (academic.oup.com)

Which anti-TNF drugs are used in IBD?

Several anti-TNF medicines are used for IBD in the United States. Brand names vary, and many now have biosimilars.

*Exact approvals depend on country and age group.

Infliximab is given by weight-based IV infusion at weeks 0, 2, and 6, then usually every 8 weeks. Adalimumab, certolizumab, and golimumab are given as injections every 1–4 weeks after a higher “loading” dose at the start. (academic.oup.com)

How are anti-TNF biologics used in Crohn’s and UC?

Anti-TNFs are typically used for:

• Moderate to severe Crohn’s disease or ulcerative colitis

• Steroid-dependent or steroid-refractory disease

• Fistulizing or perianal Crohn’s disease

• Patients with high risk features, such as deep ulcers or early complications (academic.oup.com)

Guidelines support using advanced therapies such as infliximab or other anti-TNFs early, rather than cycling through repeated steroid courses. This “treat-to-target” approach aims for symptom control and healing seen on scopes or imaging. (academic.oup.com)

Sometimes anti-TNFs are used alone. In other cases, they are combined with an immunomodulator such as azathioprine or methotrexate. Combination therapy can lower the risk of antibodies against the biologic and may improve durability of response, especially with infliximab. (gastro.org)

If symptoms return, clinicians may use therapeutic drug monitoring (TDM) to measure drug levels and anti-drug antibodies, then adjust dosing or switch medicines. (gi.org)

Safety and monitoring

Common side effects

More common side effects include:

• Infusion reactions with infliximab, such as flushing, chest discomfort, or shortness of breath during or after the infusion

• Injection site pain, redness, or swelling with self-injected drugs

• Headache, fatigue, or mild respiratory infections

These are usually mild, but infusion reactions can sometimes be severe and need urgent attention. (pfizermedical.com)

Serious infections

Because TNF is important for fighting certain germs, anti-TNF treatment increases the risk of serious infections that can require hospitalization or be life-threatening. These include:

• Tuberculosis (TB), often as reactivation of quiet infection

• Invasive fungal infections, such as histoplasmosis or aspergillosis

• Opportunistic infections, including Legionella, Listeria, and viral infections such as hepatitis B reactivation (pfizermedicalinformation.com)

Key safety steps before starting anti-TNFs usually include:

• Screening for latent tuberculosis

• Checking hepatitis B status and treating or protecting as needed

• Reviewing infection history and current symptoms

• Updating vaccines with non-live vaccines where possible (pfizermedicalinformation.com)

During treatment, any fever, severe cough, shortness of breath, painful rash, or unexplained weight loss should prompt quick medical review.

Cancer and skin risks

All anti-TNF products carry a boxed warning about lymphoma and other malignancies, especially in children and young adults. A rare cancer called hepatosplenic T‑cell lymphoma has been reported mainly in adolescent and young adult males with Crohn’s or UC who were on both an anti-TNF and a thiopurine. (pfizermedicalinformation.com)

People with IBD already have a higher baseline risk of non-melanoma skin cancers, and several studies show that long-term immunosuppressive therapy, including thiopurines and biologics, can further increase this risk. (pubmed.ncbi.nlm.nih.gov)

Preventive care guidelines advise:

• Sun protection and regular dermatology or primary care skin checks

• Extra attention to skin screening in anyone on thiopurines or long-term biologics (guidelinecentral.com)

Other important risks

Less common but important issues include:

• Worsening or new heart failure in some patients

• Demyelinating disease (conditions similar to multiple sclerosis)

• Lupus-like reactions, with joint pain and specific antibodies

• Worsening psoriasis in a minority of patients

These are uncommon, but unexplained neurologic symptoms, new severe rash, or new shortness of breath and leg swelling need urgent evaluation. (fda.gov)

Regular blood work (such as complete blood count and liver tests) is often checked, especially when anti-TNFs are combined with other immunosuppressants.

Vaccines, pregnancy, and breastfeeding

Vaccines

Anti-TNF treatment counts as immune-modifying therapy, so vaccine planning is important:

• People on anti-TNFs should receive all age-appropriate non-live vaccines, including influenza, pneumococcal, COVID‑19, hepatitis A and B, HPV, and the inactivated shingles vaccine. (guidelinecentral.com)

• Live vaccines (for example, MMR, varicella, live nasal flu, yellow fever) are generally avoided while on anti-TNF therapy. Whenever possible, live vaccines are given at least several weeks before starting treatment. (journals.lww.com)

Household members can usually receive their routine vaccines, which helps protect the person with IBD. (journals.lww.com)

Pregnancy and breastfeeding

Most current data and expert guidelines suggest that continuing anti-TNF therapy in pregnancy is usually safer than allowing IBD to flare, because active disease increases the risk of preterm birth and other complications. (pmc.ncbi.nlm.nih.gov)

Key points from IBD pregnancy studies and guidelines:

• Infliximab, adalimumab, and certolizumab have not been linked to higher rates of birth defects, miscarriage, or early birth compared with IBD controls. (pmc.ncbi.nlm.nih.gov)

• These drugs cross the placenta mainly in the second and third trimesters, so exposed infants can carry drug levels for several months. Because of this, live vaccines for the infant are usually delayed until at least 6 months of age if there was in‑utero exposure. (ccjm.org)

• Inactive (non-live) vaccines for the baby remain on the standard schedule. (journals.lww.com)

Anti-TNF medicines appear in breast milk at very low levels, and most guidelines consider breastfeeding compatible with these drugs. (ccjm.org)

Decisions about starting, continuing, or adjusting anti-TNF biologics always need shared planning with the gastroenterology team, and often with obstetrics and other specialists, to balance IBD control with individual risk factors.