In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to tocilizumab may increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.

What is tocilizumab?

Tocilizumab is a prescription medication used for the treatment of rheumatoid arthritis. Tocilizumab is an antibody (a protein made by the body’s immune system) that binds and blocks IL-6 (a different protein that causes inflammation). Tocilizumab is used to reduce symptoms and joint damage in patients with rheumatoid arthritis (RA) and juvenile rheumatoid arthritis (JRA). Tocilizumab is given in a health care providers’s office or clinic once a month as an infusion into a vein. Tocilizumab is sold under the brand name Actemra®.

How long does tocilizumab stay in the body? Should I stop taking it before I try to get pregnant?

Individuals break down medicines at different rates. On average, it takes about 12 days for half of the medicine to leave the body. This means that about 2 months after taking the last dose of tocilizumab, most of the medicine will be gone from the body.

You should not stop taking any medication without first talking with your health care provider. The benefits of taking tocilizumab and treating your autoimmune condition during pregnancy need to be weighed against the possible risks of continuing the medication.

Can taking tocilizumab make it more difficult for me to become pregnant?

There are no studies looking at whether tocilizumab affects fertility in women. At this time, it is not known if taking tocilizumab would make it more difficult for a woman to get pregnant.

Can taking tocilizumab during my pregnancy cause birth defects?

Animal studies done by the manufacturer did not show an increased chance for birth defects when tocilizumab was used in pregnancy. One review paper discussed some cases of tocilizumab use during pregnancy, and did not report any birth defects. However, there have been no studies reporting the use of tocilizumab in human pregnancy. At this time, it is not known if the use of tocilizumab in pregnancy can increase the chance for birth defects.

Tocilizumab is a large protein. Because of this, it is thought that a very limited amount of medicine can cross the placenta (the blood connection a pregnant woman shares with her baby) and reach the developing baby during the first trimester. However, without information about the use of tocilizumab in human pregnancy, the risk to the developing baby is unknown.

Can I take tocilizumab while breastfeeding?

There have been no studies looking at the use of tocilizumab use during breastfeeding. Because tocilizumab is a very large protein, in theory it would be unlikely that very much of the medication would be able to pass into breast milk. Be sure to talk to your health care provider about all your choices for breastfeeding.

What if the father of the baby takes tocilizumab?

There are no studies looking at possible risks to a pregnancy when the father takes tocilizumab. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at: http://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

MotherToBaby is currently conducting a study looking at tocilizumab and other medications used to treat autoimmune diseases in pregnancy. If you are interested in taking part in this study, please call 1-877-311-8972.

Selected References:

  • Actemra Prescribing Information. Available online at http://www.gene.com/gene/products/information/actemra/pdf/pi.pdf. Accessed Dec 2015.
  • Hyrich KL and Verstappen SM. 2014. Biologic therapies and pregnancy: the story so far. Rheumatology (Oxford); 53(8):1377-85.
  • Ostensen M and Förger F. 2011 Treatment with biologics of pregnant patients with rheumatic diseases. Curr Opin Rheumatol 23(3):293-8.
  • Pham T, et al. 2010.Tocilizumab: therapy and safety management. Joint Bone Spine 77 Suppl 1:S3-100.
  • Rubbert-Roth A, et al. 2010 First experiences with pregnancies in RA patients receiving tocilizumab therapy. Arthritis Rheum Suppl: Annual Congress, Abstract 384.