Pregnancy 3 months after inclisiran injection: a unique case report including newborn baby monitoring

Background: Data on the safety of inclisiran, a lipid-lowering small interfering RNA (siRNA) inhibiting proprotein convertase subtilisin/kexin type 9 (PCSK9) secretion, during pregnancy are absent. Case summary: A 30-year-old woman suffering from heterozygous familial hypercholesterolaemia started treatment with inclisiran 25 weeks before the start of gestation and received a second administration 13 weeks before the start of gestation. As soon as we became aware of the unplanned pregnancy, given the absence of any data regarding the administration of inclisiran during this period, the treatment was discontinued and the pregnancy was closely monitored. After a normal and full-term gestation, birth occurred at 41 + 0 gestational weeks. The baby was female and healthy, with normal anthropometry for her gestational age; her growth and development in the first 8 months of life followed a normal course. Discussion: Potential harms to the foetus with systemic malformations have been highlighted with the genetically proxied LDL cholesterol lowering through PCSK9. To the best of our knowledge, this is the first case of pregnancy initiated few months after inclisiran administration, without reporting any adverse effect on the patient or the baby. More data are needed on the pharmacodynamics and safety of siRNAs in general, and of inclisiran in particular, to confirm that this drug could be safe even in this specific setting.