Are biological drugs safe in pregnancy?

Abstract

The introduction of biological therapies has significantly improved the outcome of inflammatory rheumatic diseases. As most of these diseases affect women and men in childbearing age, some concerns have been voiced as to the safety of these drugs in relation to reproduction and pregnancy. Data from many hundreds of pregnancies in patients affected by inflammatory bowel disease and inflammatory arthritis have suggested that exposure to anti-TNF therapies at conception and/or during pregnancy is not associated with adverse pregnancy outcomes or any increase in congenital abnormalities. However, the exposure to anti-TNFα agents, particularly to monoclonal antibodies, in late pregnancy is associated with high drug levels in the newborn and their long-term effects on children remain unknown. Therefore, limiting the use of anti-TNFα to the first 30 weeks of pregnancy is recommended to reduce fetal exposure. Live-virus vaccines should be given only when levels of anti-TNFα drugs are undetectable in the serum of infants. Studies suggest that many of these drugs do enter breast milk in small amounts, but the extent to which the infant absorbs them is less clear. Limited reports have not suggested adverse pregnancy outcomes in women whose partners were exposed to anti-TNF therapies at the time of conception. Pregnancy data for rituximab, abatacept, anakinra, tocilizumab and belimumab are limited and their use in pregnancy cannot currently be recommended.