Pregnancy may not forestall disease activity
“The results of this study demonstrate that DMT withdrawal in the context of pregnancy can lead to subclinical disease re-emergence, as evidenced by increased sNfL levels in the DMT-free period,” said Vilija G. Jokubaitis, PhD, senior research fellow in the department of neuroscience at Monash University, Melbourne. Dr. Jokubaitis was not involved in the study.
Dr. Vilija G. Jokubaitis
“Interestingly, the median EDSS score in this cohort was quite low, demonstrating that, even in women with mild disease, pregnancy may not be sufficient to protect against ongoing MS activity.” Nevertheless, 28 of the 63 women were exposed to monoclonal antibody therapy, so it is unclear whether these women have mild disease or well-managed disease on DMT, she added.
“This study provides further evidence that pregnancy planning requires advanced planning, and that therapy continuation into pregnancy should be considered, particularly in women with moderate disease activity, to protect against disease reactivation,” said Dr. Jokubaitis.
The strengths of the study include its prospective design, the investigators’ ability to describe the various DMT exposures before and during pregnancy, and the multivariable mixed-effects modeling, she added. On the other hand, the results are at the group level, individual trajectories in sNfL level are not described, and the small sample size prevented the investigators from differentiating between the effects of various DMTs on sNfL outcomes. In addition, Dr. Yaldizli and colleagues did not take time off DMT into account in the models; they considered DMT exposure as a dichotomous variable.
“More work is needed to determine the therapeutic strategies that will give women with MS the greatest protection against disease reactivation in pregnancy and post partum, whilst also protecting fetal and neonatal outcomes,” said Dr. Jokubaitis. Group studies will enable researchers to identify trends, but neurologists ultimately need to provide individualized advice to their patients. “There is a need to look at [the effect of] DMT identity, timing, and duration of DMT withdrawal on fluctuation of sNfL levels, and how these relate to baseline disease severity,” Dr. Jokubaitis added. Furthermore, researchers must compare sNfL changes in pregnancy between patients with MS and healthy women in large cohorts.
The analysis by Dr. Yaldizli and colleagues was conducted without outside funding. The Swiss MS Cohort receives funding from the Swiss MS society, Biogen, Celgene, Sanofi, Merck, Novartis, Roche, and research associations such as the International Progressive MS Alliance and the Swiss National Science Foundation. Dr. Yaldizli received grants from ECTRIMS/MAGNIMS, the University of Basel, Pro Patient Stiftung, University Hospital Basel, Free Academy Basel, and the Swiss MS Society. He has received advisory board fees from Sanofi Genzyme, Biogen, Almirall, and Novartis. Dr. Jokubaitis has received conference travel support from Merck and Roche and speakers honoraria from Biogen and Roche. These relationships are not related to the current study. Dr. Jokubaitis receives research support from the Australian National Health and Medical Research Grant and MS Research Australia.