Parents’ Aubagio Exposure Not Linked to Greater Pregnancy Risks
Maternal or paternal exposure prior to conception to the multiple sclerosis (MS) therapy Aubagio (teriflunomide) does not seem to increase the risk of adverse pregnancy events, including miscarriage, preterm birth, small newborn size, or malformations, according to the results of a recent Danish study.
About one-third of women exposed to Aubagio — prescribed to lessen MS-driving inflammation — electively terminated their pregnancies, a higher proportion than that seen in the general population. That number grew to nearly 80% among women who were actively receiving Aubagio at the time of conception.
“This nationwide population-based study did not find an increase of adverse perinatal [the period during pregnancy and just after birth] outcomes in newborns with either maternal or paternal exposure to [Aubagio] when compared with the general population,” the researchers wrote.
MS is most frequently diagnosed in women of childbearing age, and possible or planned pregnancies are an important consideration when choosing treatments.
Aubagio, marketed by Sanofi, is an approved oral therapy that works by blocking the replication of immune cells that drive the inflammatory attack in MS. However, research in animal models shows that Aubagio can disrupt normal pregnancy and cause birth defects or miscarriage (spontaneous abortion).
For this reason, Aubagio is not recommended for pregnant women or women of childbearing age who are not using reliable contraception. Also, because Aubagio is slowly eliminated from the body, it is advised that women undergo an accelerated elimination procedure if pregnancy is desired within two years of stopping treatment.
Additionally, Aubagio is detected in semen, which suggests that paternal exposure at the time of conception also is a potential risk for pregnancy complications.
However, “data on perinatal outcomes following either maternal or paternal exposure to [Aubagio] are sparse,” the researchers wrote.
To better understand these potential outcomes, a research team at the Copenhagen University Hospital, in Denmark, evaluated medical records from MS patients who received Aubagio before conception. Data was retrieved from the Danish multiple sclerosis registry, known as DMSR, and general Danish population databases.
In the analyses, a pregnancy was considered exposed to Aubagio if either parent was on treatment at the time of conception, or had discontinued treatment less than two years prior. Among MS patients, 112 pregnancies met this criteria, of which 49 had maternal exposure and 63 paternal exposure.
Of these 112 total pregnancies, 91 resulted in a live birth — which were largely full-term and healthy. Among the newborns, adverse events occurred in 13.1% of cases, with 12 such events reported.
Specifically, five preterm births and seven newborn malformations occurred among pregnancies conceived after maternal or paternal Aubagio exposure. For privacy reasons, the nature of these malformations was not disclosed.
The incidence of adverse events was comparable in the general population (12.9%), meaning there was no overall increased risk of complications with Aubagio exposure.
Among the 35 women who had discontinued treatment before conception, three pregnancies were spontaneously aborted. However, no miscarriages were reported in the 14 women who were still receiving treatment at the time of conception.
“Summarized, our results are in concordance with previous studies with very few events of malformations, well within the range of general population, likewise with the prevalence of preterm birth and spontaneous abortions,” the researchers wrote.
Elective abortions occurred more often in mothers who were on Aubagio at conception (78.6%), compared with those conceived after maternal treatment cessation (20%) — a number similar to the 18% reported for the general population.
“Women are counselled about the possible … effects of [Aubagio on birth defects] and its contraindication if planning pregnancy. Therefore, may it be likely that pregnancies occurring especially on treatment are unplanned and/or unwanted and thus more likely to be terminated,” the researchers wrote.
Since most women are recommended to undergo an accelerated Aubagio elimination procedure early in pregnancy, fetal exposure to the treatment could be relatively low, which may explain the overall lack of adverse events in humans compared with previous animal studies, the researchers noted. However, whether such procedures were actually performed in this group was not documented.
“This study is based on nationwide data including the entire Danish MS population,” the researchers wrote, adding, “The free access healthcare system in Denmark levels the impact of social inequality and improves generalizability of the results to a wider demography.”
However, while the data overall suggest that Aubagio exposure does not increase the risk of adverse events in pregnancy, the sample size still was too small to draw definitive conclusions, the team noted.
“Further research is warranted to improve the measurement of association between adverse outcomes related to [Aubagio] exposure,” they wrote.