LDL-apheresis to decrease sFlt-1 during early severe preeclampsia: Report of two cases from a discontinued phase II trial

Objective: Severe preeclampsia may require the delivery of the placenta to avoid life-threatening complications for the mother. Before 26 weeks of gestation, this often results in perinatal death. A decrease in soluble fms-like tyrosine kinase 1 (sFlt1), an anti-angiogenic factor central to the pathophysiology of the maternal syndrome, has been reported after LDL- apheresis. The present study tested whether LDL-apheresis could be used to allow women with early and severe preeclampsia to reach a gestational age where the baby had a viable chance of survival.

Study design: A phase II prospective study. Adult women were included if they had very early (<26 weeks of gestation) preeclampsia without severe (<5th percentile) intra-uterine growth retardation. Treatment consisted of two weekly sessions (90 min each) of LDL-apheresis of whole blood. The primary endpoint was the status of the baby (dead or living) at 6 months post-delivery. Sample size and stopping rules were calculated assuming a desired success rate of at least 90%.

Results: The study was interrupted for safety reasons after the inclusion of two patients: both developed secondary uncontrolled hypertension and blurred vision during the first week of treatment. The first neonate, born at 25 + 3 weeks of gestation, died of sepsis at day 5; the second, born at 26 + 2 weeks of gestation, is still alive and well. In these two patients, the impact of apheresis sessions on sFlt1 concentrations was inconsistent.

Conclusion: LDL-apheresis did not result in the prolongation of pregnancy in this phase II trial. Further studies will be needed to delineate the appropriate contours of this therapeutic strategy.