Can you get pregnant while taking Selumetinib/Cosayu?

Selumetinib (Selumetinib) is a targeted therapy drug widely used to treat neurofibromatosis type 1 (NF1) and plexiform neurofibromas (PN). As an anti-cancer drug, selumetinib has certain effects on pregnancy and lactation during medication, so special attention is required during use.

Regarding pregnancy, the use of selumetinib may pose certain risks to the fetus. Although there is currently a lack of detailed clinical data on the specific effects of selumetinib on pregnant women, selumetinib is considered to have potential risks to pregnancy based on studies of other anticancer drugs and the pharmacological properties of the drug. Especially for pregnant women, selumetinib may cause adverse pregnancy outcomes, including miscarriage or abnormal fetal development, by changing hormone levels or affecting fetal development. Therefore, pregnant women should avoid becoming pregnant during treatment with selumetinib, and it is best to conduct a pregnancy test before and during treatment to ensure that the drug is used in the absence of pregnancy.

To ensure the safety of pregnant women, it is recommended that women use effective contraceptive measures during and for a period of time after treatment. Although the active ingredient of selumetinib is mainly excreted from the body in the short term after treatment, in order to avoid potential fertility risks, contraceptive measures should be continued for at least 1 week after the end of treatment. This is because the metabolism and elimination time of the drug in the body may vary, and it is very important to avoid pregnancy during this period.

Selumetinib and its active metabolite have been shown to be passed through breast milk to nursing young children. According to research, selumetinib has a significant concentration in the milk of mice. Although its specific performance in humans requires more research data to support, based on this, breastfeeding patients should be particularly careful. Therefore, doctors usually recommend that women taking selumetinib stop breastfeeding during treatment and for 1 week after the last dose.

Reference materials：https://go.drugbank.com/drugs/DB11689