Romiplostim use safe during pregnancy, may benefit pregnant mothers with ITP

A new study conducted by James B. Bussel and team shows that romiplostim should be used during pregnancy, only when the possible benefit to the mother outweighs the potential danger to the fetus while treating maternal immune thrombocytopenia (ITP).

The findings of this article were published in the American Journal of Hematology.

ITP is the most prevalent reason for severe maternal thrombocytopenia (platelet count 50 109/L in the first and second trimesters), which occurs in one in 1000–10,000 pregnancies. ITP is defined as a solitary low platelet count (100 109/L) in the absence of other causes or associated illnesses. The absence of data on the safety of maternally given drugs for fetal development hinders the management of immune thrombocytopenia in pregnancy. Amgen Inc. started a Pregnancy Surveillance Program (PSP) to gather safety data on pregnancy and fetal and neonatal outcomes of women exposed to romiplostim during pregnancy as part of a US Food and Drug Administration postmarketing requirement.

186 women who were exposed to romiplostim from 20 days from conception through delivery were tracked by the Pregnancy Surveillance Program (PSP) from 2017 to 2020 for pregnancy, birth outcomes, and adverse events (AEs). 128 women had exposure timing information available. Seventy-one moms (38%) had prenatal exposure to romiplostim; 74 mothers (40%) had intrapartum exposure; and 44 mothers (24%) had exposure throughout the second and third trimesters, with 15 mothers having exposure during more than one trimester.

The key findings of this study were:

1. 46 (53%) of the 86 women with known pregnancy outcomes experienced at least one pregnancy-related significant adverse event (SAE); around two-thirds of these SAEs were brought on by underlying ITP.

2. Of 92 mothers whose pregnancies had known outcomes, 60 (65%) had normal pregnancies and 16 (17%) experienced problems, including term and preterm deliveries; there were also 12 (14%) spontaneous miscarriages/stillbirths, 3 (3%) ectopic pregnancies, and 1 (1%) molar pregnancy.

3. Most unusual births were the consequence of unusual pregnancies. Inguinal hernia, CMV infection, trisomy 8 with a single umbilical artery without recognized abnormalities, and the onset of autism at age 2 were the five neonatal/postnatal AEs of significance.

4. Neonatal thrombocytopenia was resolved in seven out of twelve newborns before discharge; all twelve were released.

In conclusion, in this study, no noteworthy side effects were found to indicate that romiplostim directly harmed mothers with ITP. The majority of the issues seen were ITP-related. This article shows positive outcomes for the use of romiplostim for the treatment of ITP during pregnancy as additional data are acquired.

Reference:

Bussel, J. B., Cooper, N., Lawrence, T., Michel, M., Vander Haar, E., Wang, K., Wang, H., & Saad, H. (2022). Romiplostim use in pregnant women with immune thrombocytopenia. In American Journal of Hematology. Wiley. https://doi.org/10.1002/ajh.26743