The Case for Treatment During Pregnancy
Prophylaxis against pregnancy complications in patients with autoimmune disease may be achievable, Taryn Youngstein, MBBS, consultant rheumatologist and codirector of the Centre of Excellence in Vasculitis Research, Imperial College London, London, England, told this news organization after Dr. Sammaritano’s presentation. At the 2023 American College of Rheumatology Annual Meeting, her group reported the safety and effectiveness of continuing tocilizumab in pregnant women with Takayasu arteritis, a large-vessel vasculitis predominantly affecting women of reproductive age.
“What traditionally happens is you would stop the biologic particularly before the third trimester because of safety and concerns that the monoclonal antibody is actively transported across the placenta, which means the baby gets much more concentration of the drug than the mum,” Dr. Youngstein said.
It’s a situation physicians must monitor closely, she said. “The mum is donating their immune system to the baby, but they’re also donating drug.”
“In high-risk patients, we would share decision-making with the patient,” Dr. Youngstein continued. “We have decided it’s too high of a risk for us to stop the drug, so we have been continuing the interleukin-6 [IL-6] inhibitor throughout the entire pregnancy.”
The data from Dr. Youngstein’s group showed that pregnant women with Takayasu arteritis who continued IL-6 inhibition therapy all carried to term with healthy births.
“We’ve shown that it’s relatively safe to do that, but you have to be very careful in monitoring the baby,” she said. This includes not giving the infant any live vaccines at birth because it will have the high levels of IL-6 inhibition, she said.
Dr. Sammaritano and Dr. Youngstein had no relevant financial relationships to disclose.
A version of this article appeared on Medscape.com.