Ask a GI: How Do Biologics Treat Crohn's Disease?
IBD treatment can be confusing—so we went straight to an expert for the answers.
If you've been diagnosed with Crohn's disease (CD), you've probably heard that biologics are one common treatment for people with moderate-to-severe disease. And while biologics have been on the market for a while now as a treatment for CD, there’s still a lot of misinformation out there on how they work and what they do.
That's why we asked an expert, Constance A. Pietrzak, M.D., a gastroenterologist (GI) at Advocate Medical Group in Chicago to help us answer the most common questions about using these drugs for Crohn's. Here's what you need to know.
What Are Biologics?
Biologics drugs are unique in that they’re made from proteins from living organisms in a lab, says Dr. Pietrzak.
"These medications are antibodies that bind to specific parts (proteins) of the immune response interfering with (chronically active inflammation characteristic of the disease process) inflammation," she says, and inflammation is the main issue in inflammatory bowel disease (IBD). "One common target of multiple biologics used in IBD is tumor-necrosis factor alpha (TNF-alpha)."
How Do Biologics Work to Treat Crohn's Disease?
"Biologic treatments have a distinct advantage over other therapies," says Dr. Pietrzak. These medications act on a specific target in the gut lining and help reduce the inflammatory response by blocking it directly. However, as a result of suppressing the immune response, the entire immune system is weakened and does increase your risk slightly for infection. Therefore, your doctor will test you for certain infections prior to starting a biologic and recommend that you get certain vaccinations against other infections
By targeting specific proteins, like TNF-alpha, biologics can trigger a response to slow down inflammation in your GI tract and therefore improve the disease, she says.
How Do You Take Biologics?
"Most biologics are administered as either an infusion or injection," Dr. Pietrzak says. "Infusions are usually given at an infusion center and take 30 minutes to two hours to infuse. They're usually given every four to eight weeks after an initial induction period [typically your first dose is higher than subsequent doses], depending on the medication you're prescribed."
If you choose to go the route of injections, you'll learn how to give yourself a shot. After the initial induction period, you'll inject the med every two to four weeks, she says.
What Are the Common Side Effects?
"One side effect specific to biologics is injection-site reaction, such as redness, bruising, itching, swelling, pain, or ulceration," says Dr. Pietrzak. "Other potential side effects include infusion reactions (hives, swelling, difficulty breathing, low blood pressure), infections due to lowering of the immune system as well as cough, sore throat, fevers, nausea, and stomachache."
Other very rare but serious side effects include heart failure, life-threatening blood infections, tuberculosis, and blood disorders, she adds. And in very rare cases, the blood cancer lymphoma has also been reported. To put it in perspective, though: 1.27% of people on long-term biologics experienced serious side effects compared with 1.18% of people who took a placebo drug, according to a 2011 Cochrane review.
Which Biologic Should I Take?
There are two main types of biologics currently in use for Crohn's treatment:
TNF-alpha blockers: “These inhibit the immune system’s response (inflammation) by blocking TNF-alpha,” explains Dr. Pietrzak.
Integrin-receptor blockers: These work by blocking migration of inflammatory cells across blood vessels into the GI tract, she says.
"Every patient responds differently to each biologic agent, and it is difficult to say which is more or most effective," Dr. Pietrzak adds. "When a patient responds well to one biologic, it is usually best to continue that drug for as long as the disease is well controlled."
Why Do Biologics Work for Some People But Not Others?
Sometimes, people taking biologics can develop a reaction to the drug that makes it no longer effective.
"Some individuals will make antibodies that bind to and work against the biologic drug, especially the TNF-alpha blockers," explains Dr. Pietrzak. "These are referred to as anti-drug antibodies (ADAb), and the formation of these antibodies can lead to allergic reactions or make the biologic ineffective."
Not all hope is lost if this happens, though. Thankfully, you can just switch to a different type of biologic.
How Do You Know if a Biologic Is Working?
"The best way to know if a biologic is working is if your symptoms are improving," says Dr. Pietrzak. That can take as little as a couple of months for some patients but longer for others.
"The goal with these agents is to improve and eliminate symptoms and then to keep patients symptom-free in the long term," she says. For example, one major study found that 33% of people taking the anti-TNF biologic infliximab (Remicade) reached remission after four weeks.
But Dr. Pietrzak has a word of caution: "It is important for patients to know that even if they are no longer having any symptoms, they need to continue taking their medication to prevent disease flares. If biologics are stopped, there is a good chance your symptoms can recur." That means that once you go on them, you typically stay on them indefinitely.
How Have Biologics Changed the Treatment of Crohn's Disease?
"Biologics have revolutionized the treatment of Crohn's disease," says Dr. Pietrzak. While patients with mild Crohn's may not ever need biologics, patients with moderate-to-severe disease that didn’t respond to other types of available therapies—like aminosalicylates (5-ASAs), corticosteroids, and immunomodulators—have another effective option, she says.
What Else Should Crohn's Patients Know About Biologics?
"Biologics are extremely effective medications in treating Crohn's," reiterates Dr. Pietrzak. Make sure to discuss them with your doctor as a potential treatment option. She can help you weigh the pros and cons for your specific situation.
Also, Dr. Pietrzak says it's key to keep in close contact with your health care team when you’re on a biologic drug. Let them know if you experience any new symptoms or side effects.
"Also, it is imperative that you do not stop these medications on your own [since they’re intended to be taken indefinitely]," she advises. "If you do, only restart them with the guidance of your doctor, and not on your own."