Nobody knew how much of an impact COVID-19 would have when it first appeared on the scene. Now, as of May 20, 2021, the novel coronavirus pandemic has led to 165 million cases – and an associated 3.42 million deaths – worldwide. In the United States alone, there have been 33.1 million cases and an associated 587,000 deaths. The introduction of the COVID-19 vaccine has helped mitigate the risk. But for some patients, there is a question of whether or not it is safe to receive the vaccine – or whether the intended schedule is safe. However, according to MedPage Today, patients with inflammatory bowel disease (IBD) treated with infliximab should not delay their second vaccine dose.

In fact, according to a study performed by British researchers, infliximab treatment reduced the immunogenicity of the Pfizer and AstraZeneca vaccines. If patients are also using an immunomodulator, the immunogenicity falls even further. Thus, it is crucial for patients with IBD to receive both doses of their vaccine under the intended schedule. Interested in seeing the research? Check out the full findings published in Gut: An International Journal of Gastroenterology and Hematology. 

The Research

Immunogenicity

During their study, researchers explored data from the CLARITY IBD study, which encompassed 1,293 English and Scottish patients with IBD. In re-exploring their initial analysis, researchers determined that patients treated with infliximab had lower immunogenicity and a weaker antibody response to COVID-19 infection. This was not seen in patients treated with vedolizumab.

But what does reduced immunogenicity mean? According to AstraZeneca:

Immunogenicity is a more complex measure of how well a vaccine works, and measures the type of immune responses that the vaccine generates and their magnitude over time. This analysis provides valuable information not only on how well a vaccine is working, but can support aspects such as the determination of dosage and immunization schedules.

Basically, measuring immunogenicity allows researchers to determine:

• How the immune system is responding
• The scope of the immune response
• Whether or not these responses are beneficial or undesirable

In regards to COVID-19 vaccines, immunogenicity can be difficult. Is the vaccine helping to provide a strong immune response? What does a strong immune response, in regards to COVID-19, look like? AstraZeneca continues:

To determine if a vaccine is able to effectively produce a strong and sustained immune response, a vaccine-induced immune response would typically be compared to the immune response found in people who have known immunity to a disease. Where the response is comparable or greater, then the vaccine shows promise of being effective.

Because COVID-19 is still being researched and understood, one measure of immune response researchers are able to look at is the amount of neutralizing antibodies.

IBD and the COVID-19 Vaccine

Altogether, the study encompassed data from 1,293 patients with IBD. Patients had received either the Pfizer/BioNTech BNT162b2 mRNA vaccine or the Oxford/AstraZeneca ChAdOx1 nCoV-19 adenovirus-vector vaccine. A slight majority of patients were male. Additionally, most patients (91%) were white. Approximately 2/3 of patients received infliximab treatments, while the remaining patients received vedolizumab.

After a 3-10 week period, following the initial vaccination, patients’ spike antibodies were evaluated. Researchers determined that:

• Patients treated with infliximab and an immunomodulator had the least seroconversion, or the development of specific antibodies. Alternately, those receiving vedolizumab had the highest rates of seroconversion.
• Being older in age, smoking cigarettes, and having Crohn’s disease were also associated with less seroconversion. Alternately, patients who were not white had higher levels of seroconversion.
• After receiving a second vaccination, most patients with IBD were able to develop higher antibody levels.

Ultimately, the researchers highlight how patients with IBD should continue with their dosing schedule as assigned and without delay. Until patients are able to receive their second vaccine, they should continue practicing social distancing and other protective measures.

Inflammatory Bowel Disease (IBD)

Altogether, inflammatory bowel disease (IBD) consists of a group of digestive tract-related conditions, such as Crohn’s disease or ulcerative colitis (UC). In each condition, patients experience digestive tract inflammation. The overall cause of IBD is currently unknown. However, doctors believe that IBD results from some form of immune malfunction in which the immune system mistakenly attacks cells within the digestive tract. Additional risk factors include cigarette use, a family history of IBD, being of Ashkenazi Jewish descent, age (being 30 or younger), or high stress. Without treatment and disease management, IBD can result in dangerous or life-threatening complications.

Typically, IBD occurs in active periods, punctuated by periods of remission. Symptoms of IBD include:

• Unintended weight loss
• Bloody stool
• Appetite loss
• Fatigue
• Diarrhea
• Rectal bleeding
• Abdominal pain and cramping

As described earlier, IBD can also result in serious complications. If you have IBD and experience any of the following, please speak to your doctor immediately:

• Blood clots in the veins or arteries
• A sudden change in bowel habits
• Primary sclerosing cholangitis, which causes bile duct scarring and liver damage
• Colon cancer
• Skin, eye, and joint inflammation
• Bowel obstructions
• Anal fissures
• Malnutrition and/or dehydration