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Infliximab - developing antibodies.

So it's coming up to a year of having infliximab infusions at 8 week intervals. Iv just been told I'm unfortunately starting to develop antibodies. My Dr has said once they have done so more tests and colonoscopy they will have a better idea of the next step - shorter intervals or a new med. I'm just curious of what others have done? I was quite reluctant to start the infusions but they convinced me with the explanation that it was the best possible approach with how my Crohns was presenting. Obviously this is now making me wonder if a new medication will be less effective, especially as I was responding really well. Also currently taking 6mp, allopurinol & pentasa. Like I said just curious of what could happen (in the UK, if that makes any difference) and also did anyone feel any side effects from developing antibodies, I definitly didn't get the same boost I usually do but I had figured that was just life!!
Thanks for any input.


Well-known member
San Diego
The main noticeable effect of developing antibodies the infliximab is that the drug loses its effectiveness and the Crohn's symptoms start to come back. There are generally not other or new harmful side effects of the antibodies.

The common first step once the drug starts to lose its effectiveness is to increase the dose in order to restore the dropping concentration in your blood. That's what they are suggesting with the "shorter intervals." If the interfering antibody concentration is too high then the next step is commonly to change to another biologic. They usually start with another anti-TNF such as adalimumab (Humira), golimumab (Simponi), or certlizumab pegol (Cimzia). If those don't work or are not good options for some reason then there are the newer drugs vedolizumab (Entyvio) and uetekinumab (Stelara) that are drugs that act against integrin and IL-12/23 respectively. All of these drugs work to slow the immune system down in some way and hence provide relief from the Crohn's. Their effectiveness will not be compromised by the anti-infliximab antibodies. However, there is a chance you may eventually develop antibodies against them just as you did against infliximab. But one does not guarantee the other.

So as you can see there are still many options for you if infliximab no longer works.
Thank you for the info, i couldnt really get a huge amount out of my Dr but this has definately lifted some of the concern.

Best wishes.