Rituximab is a chimeric human-murine IgG1 monoclonal antibody produced by recombinant DNA technology administered in the treatment of non-Hodgkin’s lymphoma, chronic lymphocytic leukaemia, rheumatoid arthritis, and granulomatosis with polyangiitis and microscopic polyangiitis. Rituximab acts via CD20+ B-cell depletion.
Data specific to rituximab use during pregnancy are limited to case reports and uncontrolled case series. There are extremely limited data available for first trimester-exposed pregnancies (n=14), but data from these and a larger number of preconceptual exposures (<6 months prior to conception) mainly describe healthy outcomes. Although data from uncontrolled studies and case reports do not indicate that rituximab use during pregnancy is associated with adverse pregnancy outcomes, the data are too limited to rule out any risks. Rituximab is not expected to cross the placenta during the first trimester, therefore direct teratogenic effects are not anticipated.
Maternal autoimmune/inflammatory conditions are known to be associated with certain adverse pregnancy outcomes, such as miscarriage, preterm delivery and low birth weight. Ensuring adequate control of the maternal condition may therefore decrease the risk of certain adverse pregnancy outcomes.
Rituximab exposure in utero has been demonstrated to deplete neonatal B-cells. Guidance from Public Health England (PHE) [issued 2017] specifies that live vaccines should not be used until the infant is six months old following in utero biologic immunosuppressant exposure.
Due to the lack of data, additional fetal monitoring may be warranted on a case-by-case basis. Other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.